2- needle, high-speed, unison-feed …lu-2212,lu-2220 em.pdf29227501 no.e306-04 engineer’s manual...

29227501No.E306-04

ENGINEER’S MANUAL

1-NEEDLE, HIGH-SPEED, UNISON-FEED LOCKSTITCH MACHINE WITH VERTICAL-AXIS LARGE HOOKAND AUTOMATIC THREAD TRIMMER

LU-2210N-7 LU-2210W-7

®

1- NEEDLE, HIGH-SPEED, UNISON-FEED LOCKSTITCH MACHINE WITH VERTICAL-AXIS LARGE HOOKAND AUTOMATIC THREAD TRIMMER (2P DIAL)

LU-2212N-7

2- NEEDLE, HIGH-SPEED, UNISON-FEED LOCKSTITCH MACHINE WITH VERTICAL-AXIS LARGE HOOKAND AUTOMATIC THREAD TRIMMER

LU-2260N-7 LU-2260W-7

1- NEEDLE, HIGH-SPEED, UNISON-FEED LOCKSTITCH MACHINE WITH VERTICAL-AXIS LARGE HOOKAND AUTOMATIC THREAD TRIMMER (NEEDLE THREAD CLAMP DEVICE/2P DIAL)

LU-2220N-7

IntroductionThis Engineer’s Manual is for technical service engineers. In the instruction manual for the maintenance engi-neers of sewing machines and sewing workers in a sewing factory, how to operate a sewing machine is alsodescribed in detail. However, in this manual, [Adjustment Procedure], [Results of Value Change for Adjustment],and the roles of each component are described: these are not included in the instruction manual.When maintenance is performed for our sewing machines, refer not only to this manual, but also to the instructionmanual and parts list.

This engineer’s manual describes the basic adjusting values as the reference values in the first page, and theobserved events caused by sewing and mechanical faults as the [Results of Value Change for Adjustment] and[Adjustment Procedure] in the second page.

CONTENTS

1. Specifications ......................................................................................................... 1

2. Model Numbering System ...................................................................................... 2(1) LU-2210N/W-7 ............................................................................................................................ 2(2) LU-2212N-7 ................................................................................................................................ 3(3) LU-2260N/W-7 ............................................................................................................................ 4(4) LU-2220N-7 ................................................................................................................................ 5

3. Standard Adjustment .............................................................................................. 6(1) Types and Names of Gradations on the Hand-wheel ............................................................ 6(2) Sewing Speed............................................................................................................................ 7(3) Needle Entry .............................................................................................................................. 8

1) Needle entry in the needle slot of the feed dog in the lateral direction ............................................................ 8

2) Needle entry in the needle slot of the feed dog in feeding direction

(LU-2210N/W-7, 2260N/W-7, 2212N-7) ................................................................................................................ 10

3) Needle entry in the needle slot of the feed dog in feeding direction (LU-2220N-7) ....................................... 12

(4) Needle-to-Hook Relation ........................................................................................................ 141) Height of the Needle Bar ...................................................................................................................................... 14

2) Clearance between the Needle and the Blade Point of Hook........................................................................... 16

3) Timing between the Needle and the Hook ......................................................................................................... 18

(5) Clearance between the Throat Plate and the Inner Hook Stopper ..................................... 20(6) Timing of the Cloth Feed Action ............................................................................................ 22

1) Horizontal Feed Timing ........................................................................................................................................ 22

2) Vertical Feed Timing ............................................................................................................................................ 22

3) Upper Feed Timing ............................................................................................................................................... 24

4) Height of the Feed Dog ........................................................................................................................................ 26

5) Amount of alternating vertical movement of the walking foot and presser foot

(Balance between the lifting amounts of the presser foot and walking foot) ............................................... 28

(7) Adjustment of the Feed Mechanism...................................................................................... 301) Zeroing of the feed adjusting mechanism ......................................................................................................... 30

2) Stitch length in the normal feed and reverse feed ............................................................................................ 32

3) 2P Adjustment (for LU-2212N-7 and LU-2220N-7) ............................................................................................. 34

(8) Position of the Reverse Feed Connecting Arm/the amount of condensation ................... 36(9) Bobbin Winder ......................................................................................................................... 38

1) Bobbin Winder Friction Wheel Adjustment ....................................................................................................... 39

2) Bobbin Winding Amount Adjustment ................................................................................................................. 39

(10) Thread Trimmer Device (for LU-2210N/W-7 and LU-2260N/W-7) ...................................... 401) Counter Knife........................................................................................................................................................ 40

2) Clamp Spring ........................................................................................................................................................ 40

3) Knife Pressure ...................................................................................................................................................... 40

4) Moving Knife Driving Arms A, B and C .............................................................................................................. 40

(11) Thread Trimmer Device (for LU-2212N-7) ........................................................................... 421) Positions of Counter Knife and Clamp Spring .................................................................................................. 42

2) Counter Knife Base Position ............................................................................................................................... 42

3) Knife Pressure ...................................................................................................................................................... 42

4) Moving Knife Driving Arms A, B and C .............................................................................................................. 42

5) Height of the Moving Knife (for the right-hand side hook) (for LU-2210N/W-7,

LU-2212N-7 and LU-2260N/W-7) .......................................................................................................................... 44

6) Height of the Moving Knife (for the left-hand side hook) (for LU-2260N/W-7) ................................................ 46

7) Thread Trimmer Cam (for LU-2210N/W-7 and LU-2260N/W-7) ......................................................................... 48

8) Thread Trimmer Cam (for LU-2212N-7) .............................................................................................................. 50

(12) Thread Trimmer Device (LU-2220N-7) ................................................................................. 521) Positioning for the thread trimming cylinder joint ......................................................................................... 52

2) Counter knife (adjustment of movement) (positioning for the counter knife base stopper ....................... 54

3) Counter knife (adjustment of right and left positioning) ............................................................................... 56

4) Moving knife (adjustment of vertical positioning) .......................................................................................... 58

5) Counter knife (adjustment of vertical positioning) ......................................................................................... 58

6) Thread guide mounting position ...................................................................................................................... 60

7) Adjustment of knife presser ............................................................................................................................. 60

8) Moving knife driving arm and initial position of the moving knife ............................................................... 62

9) Adjustment of gap between the moving knife driving arm and the moving

knife driving arm stopper.................................................................................................................................. 64

10) Mounting position of the moving knife return plate ....................................................................................... 64

11) Adjustment of timing for the thread trimming cam ........................................................................................ 64

12) Clamp spring mounting position ..................................................................................................................... 66

13) Explanation of the solenoid valve .................................................................................................................... 68

(13) Opener .................................................................................................................................... 701) Timing of the Opener ........................................................................................................................................... 70

2) Clearance between the opener and the protruding section of the inner hook............................................... 70

(14) Presser Lifting Unit ............................................................................................................... 721) Presser Lifting Amount ........................................................................................................................................ 72

2) Presser Lifting Cylinder ....................................................................................................................................... 72

(15) Safety Mechanism ................................................................................................................. 741) Releasing Torque Adjustment ............................................................................................................................. 74

2) How to reset the Safety Mechanism ................................................................................................................... 74

(16) Lubricating Unit ..................................................................................................................... 761) Oil Distribution Diagram ...................................................................................................................................... 76

2) Supplying and Replacing Oil ............................................................................................................................... 76

3) Filter Replacement Procedure ............................................................................................................................ 78

4) Adjusting the amount of oil in the hook and cleaning the hook filter ............................................................. 78

(17) Aperture Plate Removal Procedure (for LU-2212N-7) ........................................................ 801) Removal Procedure of Aperture Plate ............................................................................................................... 80

2) Attachment Procedure of Aperture Plate ........................................................................................................... 80

3) Adjustment of 2P Cylinder Connecting Link ..................................................................................................... 80

(18) Aperture Plate Removal Procedure (for LU-2220N-7) ........................................................ 821) Removal Procedure of Aperture Plate ............................................................................................................... 82

2) Attachment Procedure of Aperture Plate ........................................................................................................... 82

3) Adjustment of 2P Cylinder Connecting Link ..................................................................................................... 82

4. Various Switches................................................................................................... 84(1) Operation Switches................................................................................................................. 84(2) Knee Switch ............................................................................................................................. 84

5. Parts Replacement ................................................................................................ 86(1) How to replace the Needle Clamp (LU-2260N/W-7) .............................................................. 86(2) Replacement of the Presser Adjusting Spring ..................................................................... 88(3) How to replace the Timing Belt .............................................................................................. 90(4) How to change from 1-needle to 2-needle specifications (LU-2210N-7 →→→→→ LU-2260N-7) ...... 96

6. Bed Height Adjustment......................................................................................... 99

7. Parts to be carefully tightened........................................................................... 100

8. Parts to be fixed with LOCK-TITE Paint ............................................................ 101

9. Maintenance Parts List ....................................................................................... 102

10. Mechanism Adjusting Procedure Chart at a Glance ...................................... 103

11. Troubles in Sewing and Corrective Measures ................................................ 105(1) Related to Sewing ................................................................................................................. 105(2) Related to Thread Trimmer ....................................................................................................111

12. Replaceable Gauge Table ................................................................................. 114(1) For LU-2210N/W-7, LU-2212N-7 and LU-2220N-7 ............................................................... 114(2) For LU-2260N/W-7 ................................................................................................................. 116

13. Machine head wiring (with thread trimmer only) ........................................... 117(1) Connector from the machine head

(LU-2210N/W-7, LU-2260N/W-7 (other than LU-22*0*-0-*-0B) ............................................ 117(2) Connectors from solenoid valve (asm.) (40024969)

(LU-2210N/W-7, LU-2260N/W-7 (other than LU-22*0*-0-*-0B) ............................................ 117(3) Connector from the machine head

(For LU-2210N/W-7, LU-2260N/W-7 (LU-22*0*-0-*-0B) ........................................................ 118(4) Connector from solenoid valve (asm.) (40025724)

(For LU-2210N/W-7, LU-2260N/W-7 (LU-22*0*-0-*-0B) ........................................................ 118(5) Connector from the machine head (LU-2212N-7) ............................................................... 119(6) Connector from solenoid valve (asm.) (40025981) (LU-2212N-7) ..................................... 119(7) Connector from the machine head (LU-2220N-7) ............................................................... 120(8) Connector from solenoid valve (asm.) (40063828) (LU-2220N-7) ..................................... 120

14. Timing Chart ...................................................................................................... 121

15. Table Dimension Diagram ................................................................................ 122

– 1 –

1. SpecificationsNo. Item Specification

1 Model LU-2210N-7 LU-2210W-7 LU-2212N-7 LU-2220N-7 LU-2260N-7 LU-2260W-7

2 Model name

(Touch-back unit, auto-lifter device, with lifting device)

3 Applications For medium-weight materials, car seats and furniture

4 Sewing speed Max. 3,500 rpm (Varies according to sewing conditions).

5 Needle Schmetz 134 x 35R, Nm 110 to Nm 160 (Standard Nm 140)

6 Thread #4 to #30 #5 to #20

Max. 6 mm for both normal7 Stitch Length Max. 9 mm for both normal feed stitching and reverse feed stitching feed stitching and reverse feed

stitching

8 Presser foot lift Using hand lifter: 9 mm, Using knee lifter: 15.5 mm (equipped with a reversing device)

9 Stitch length regulating method Using a dial

10 Stitch length regulating method for 2P Using a dial

11 Reverse feed stitching Externally mounted air pressure cylinder (with a touch-back switch and hand lever)

12 Thread take-up lever Link type

13 Needle bar stroke 33.8mm

14 Needle gauge

15 Hook 1.6-fold horizontal axis hook 2-fold horizontall axis hook 1.6-fold horizontal axis hook 2-fold horizontall axis hook(Automatic lubrication hook) (Automatic lubrication hook) (Automatic lubrication hook) (Automatic lubrication hook)

16 Opener Opener shaft eccentric cam speed reduction system (The opener travels by one stroke while the hook rotates twice).

17 Feed mechanism Using an arc block slider

18 Hook driving system Screw gear

19 Thread trimmer

20 Tension release system Using the push solenoid for actuating together with the thread trimmer

Adjustment of the amount of21 alternating vertical movement of Using a dial (peripheral cam)

the walking foot and presser foot

22 Using a timing belt

23 Bobbin winder Built in the arm

24 Lubrication system Automatic lubrication system

25 Oil return flow Circulated with the plunger and felts

26 Lubricating oil JUKI New Defrix Oil No. 1 (Equivalent to ISO VG7)

27 Space under the needle 263.5 mm (Distance from the center of the presser bar to the bottom of the arm)

28 Bed size 517mm x 178mm

29 Automatic lifter Externally mounted pneumatic cylinder

30 Lifting device (DL)

31 2P DIAL unit Pneumatic cylinder sheathing system

32 Needle thread clamp device

33 Weight of machine head Approx. 55 kg Approx. 58 kg

34 Transmission belt HM V belt

35 Motor used SC-510 +M51

36 Motor pulley Engraved mark (outer periphery): 90 / Effective diameter: ø 85mm

37 Hand wheel (Effective diameter) Effective diameter: ø 76.023mm

38 Air pressure/ 0.5MPa 0.5MPa 0.5Mpa 0.5MpaAir consumption 0.736dm3/min (ANR) 1.078dm3/min (ANR) 1.377dm3/min (ANR) 0.736dm3/min (ANR)

39 Single phase 100V / Three-phase 200V / 425VA

1-needle, high-speed, unisonfeed lockstitch machine withvertical-axis large hook andautomatic thread trimmer

(Needle thread clamp device/2P DIAL)

Pneumatic cylinder with a built-in type speed controller to control the speed corresponding to the amountof alternating vertical movement of the walking foot and presser foot


1-needle, high-speed, unisonfeed lockstitch machine withvertical-axis large hook andautomatic thread trimmer(Specially specified for 2P

DIAL)


6mm•8mm•10mm(Standard)•12mm•20mm∗

Rocks around the hook(peripheral cam and solenoid)

Rocks around the hook(groove cam and

air cylinder system)

Rocks around the hook(peripheral cam and solenoid)

Pneumatic cylindersheathing system

(with switch)

∗ Needle Gauge:The gauge from 4 mm up to 36 mm (for LU-2260N-7) or from 4 mm up to 30 mm (for LU-2260W-7) is available with special specifications.

Main shaft and hook driv-ingshaft driving system

Source voltage/Power consumption

– 2 –

2. Model Numbering System(1) LU-2210N/W-7

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

L U 2 2 1 0 7 0 B –

7 Hook Code

N Large hook (1.6-fold)

W Double size hook (2.0-fold)

9 Presser Foot

A Standard

B For overlapped section

C For urethane

D Right-single-sided foot

E Left-single-sided foot

F For piping ø3

G For piping ø4

H For piping ø5

J For piping ø6

K Presser area small

11 DL Device

Z Without DL device

A DL device without knee switch

B DL device with knee switch

* The pneumatic automatic presser foot lifter isequipped as standard.

15 Option

Z Without option

A AE9 (Bobbin thread level detection device)

* Applicable only for the machine with Hook Code N(Large Hook)

18 Accessory Specification Code

A Standard

B For Europe

D For United States

E For Japan

8 Walking Foot

A Standard

B For urethane

C Right-single-sided foot

D Left-single-sided foot

E For piping ø3

F For piping ø4

G For piping ø5

H For piping ø6

J Adjustable type for piping ø3

K Adjustable type for piping ø4

L Adjustable type for piping ø5

M Adjustable type for piping ø6

10 Feed Dog

S Standard (with groove)

A Without groove

B For thin thread (2.5 x 1.6)

17 Specification Code for Destination

A Standard

B For Europe

E For Japan

– 3 –

(2) LU-2212N-7

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

L U 2 2 1 2 N B 7 0 B –

7 Hook Code


9 Presser Foot

A Standard


C For urethane



F For piping ø3

G For piping ø4

H For piping ø5

J For piping ø6


11 DL Device


15 Option

Z Without option



A Standard

B For Europe

D For United States

8 Walking Foot

A Standard

B For urethane



E For piping ø3

F For piping ø4

G For piping ø5

H For piping ø6





10 Feed Dog


A Without groove



A Standard

B For Europe

E For Japan

– 4 –

(3) LU-2260N/W-7

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

L U 2 2 6 0 S S 7 0 B –


A Standard

B For Europe

E For Japan

8 Stitch Length Code

S 6mm

7 Hook Code

N Large hook (1.6-fold hook)

W Double size hook (2.0-fold hook)

9 Needle Gauge Code

B 6.0mm

C 8.0mm

D 10.0mm

E 12.0mm

J 20.0mm

11 DL Device

Z Without DL device

A DL device without knee switch


* The pneumatic automatic presser footlifter is equipped as standard.

15 Option Code

Z Without option


* Applicable only for the machine with Hook CodeN (Large Hook)


A Standard

B For Europe

D For United States

E For Japan

10 Walking Foot, Presser Foot and Feed Dog

S Standard

– 5 –

(4) LU-2220N-7

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

L U 2 2 2 0 N B 7 0 B –

7 Hook Code


9 Presser Foot

A Standard


C For urethane



F For piping ø3

G For piping ø4

H For piping ø5

J For piping ø6


11 DL Device


15 Option

Z Without option



A Standard

B For Europe

D For United States

8 Walking Foot

A Standard

B For urethane



E For piping ø3

F For piping ø4

G For piping ø5

H For piping ø6





10 Feed Dog



C For thick thread (wide groove width)


A Standard

B For Europe

E For Japan

– 6 –

(1) Types and Names of Gradations on the Hand-wheel

Standard Adjustment

3. Standard Adjustment

Adjust the timing of each operation of the sewing machine while aligning the upper side of the hand-wheelpointer with the corresponding gradation on the hand-wheel . The gradation on the hand-wheel andthe pointer on it can be observed through the notch on the belt cover.

Scale plate of thehand-wheel

Timing of the opener(Refer to (13)).

Timing of thread trim-ming action[Refer to (11)-8).](LU-2212N-7)

Range of the upper stopposition

Timing of thread trimming action[Refer to (11)-7).](LU-2210N/W-7, LU-2260N/W-7)

Feed rock timing (Refer to (6)-1).

Aligning the pointer on the machine arm(highest dead point of the needle bar)

H

Direct io

n

of rotatio

n

L

KJ

HG

F

EDC

B

A

AB

CD

EF

HG

JK

L

Timing between the needle and the hook (Refer to (4)-3).Amount of alternating vertical movement of the walking foot and presser foot (Refer to (6)-5).Height of the feed dog (Refer to (6)-4).Thread trimmer cam timing [Refer to (12) – 11)] (LU-2220N-7)

– 7 –

(2) Sewing Speed

Standard Adjustment

The maximum sewing speed is set according to the sewing conditions as shown in the lists below. Set themaximum sewing speed according to each sewing condition so that the sewing speed does not exceed the setvalue.

1. Maximum sewing speed according to the amount of alternating vertical movement of the walking foot andpresser foot, and sewing pitch.(1) If the sewing pitch is 6mm or less, it shall be within the range between upper and lower limit values.

Amount of alternating vertical movement (mm) Max. sewing speed (rpm)

1 to 6.5 2, 000

Needle Gauge (mm) Max. Sewing Speed (rpm)

4 to 10 3, 500

12 to 20 3, 300

22 to 30 3, 000

32 to 36 2, 500

Sew

ing

spee

d (r

pm)

Amount of alternating vertical movement (mm)

(2) For sewing pitch of more than 6 mm, but less 9 mm or less (for LU-2210N/W-7, LU-2212N-7 andLU-2220N-7)

2. Maximum sewing speed according to the needle gauge (only for LU-2260N/W-7)

Upper limitvalue

Lower limitvalue

– 8 –

(3) Needle Entry

Standard Adjustment

1) Needle entry in the needle slot of the feed dog in the lateral direction

Needle entry pointThe center of the needle slot in the feed dog shouldbe aligned with the center of the needle.Requirements:• Needle bar should be brought to the lowest dead point.• The stitch dial should be set to [0] on the scale.

Thrust collars

Toward the oppositeside of the operator

When tightening the thrust collarset screw , tighten it whilerocking the needle bar frame toward the side opposite from theoperator.

Needle bar framedriving shaft

Assemble the thread take-up crankshaft and the threadtake-up crank with the shaft pressed against the endface of the crank.

Assemble the thread take-up crank and the thread take-up crank-

shaft support so that they can beseen to be in end-to-end contact witheach other while leaving no clear-ance between the end faces.

Counterweight

Needle bar crank

Needle bar crank rod

Thread take-uplever

Needle

– 9 –

Adjustment Procedure Results of Improper Adjustment

1. Set the dial to adjust the amount of alternating the vertical movementof the walking foot and presser foot to [1] on the scale.

2. Remove the top cover.3. Set the stitch dial to maximum value on the scale.4. Loosen the set screw of the reverse feed cylinder. (Except for LU-

2212N-7 and LU-2220N-7)5. Remove the reverse feed cylinder. (Except for LU-2212N-7 and LU-

2220N-7)6. Remove the aperture plate.7. Loosen the set screw of the needle bar connecting rod.8. Loosen the set screws of the thrust collars of the needle bar

frame driving shaft.9. Remove the presser spring regulating dial .10. Loosen the set screw of the presser spring regulating arm shaft.11. Remove the presser adjusting spring .12. Remove the presser adjusting arm .13. Remove the presser spring regulating arm shaft .14. Loosen the set screw of the thread take-up crankshaft.15. Loosen the set screw of the thread take-up crankshaft support.16. Draw out the thread take-up crankshaft .17. Remove the triangular lever shafts and .18. Adjust the needle entry.19. Fasten the set screws of the thrust collar.20. Adjust the position of the thread take-up crankshaft support in

accordance with the position of the thread take-up crank .21. Fasten the set screw of the thread take-up crankshaft support.22. Insert the thread take-up crankshaft into the thread take-up crank

until the shaft reaches the end face of the thread take-up crank.23. Fasten the set screw of the thread take-up crankshaft.(Caution) Tightening torque shall be 2.45 to 2.94N•m (25 to

30kgf•cm).24. Attach the triangular lever shafts and in place.25. Attach the presser spring regulating arm in place.26. Attach the presser spring regulating arm shaft in place.27. Fasten the set screw of the presser spring regulating arm shaft.28. Attach the presser adjusting spring .29. Attach the presser spring regulating dial in place.30. Set the stitch dial to [0] on the scale.31. Adjust the needle entry in the needle slot of the feed dog in the

feeding direction.32 . Fasten the clamping screw of the needle bar connecting rod.(Caution) Fasten the screw with a tightening torque of 7.84 to

8.82N•m (80 to 90 kgf•cm).33. Attach the aperture plate in place.34. Attach the reverse feed cylinder in place, and fasten the set screw

in it. (Except for LU-2212N-7 and LU-2220N-7)

6’ For how to remove or attach theaperture plate in LU-2212-N-7and LU-2220N-7, refer to [3-(17) and (18) Aperture PlateRemoval Procedure].

17’ Tilt the triangular lever ,which has been set free, towardthe presser bar lifting lever. Atthis time, eliminate a thrust playat the needle bar frame andfasten the set screw while os-cillating the needle bar frame toward the operator.

20’ At that time, move the threadtake-up crank shaft support and adjust so that the end faceof the thread take-up crankshaftsupport come in slight con-tact with the end face of thethread take-up crank, but pro-viding no play between them.

21’ Fasten the set screw whilemaking the contact point of thethread take-up crankshaft sup-port with the screw straightup.

31’ Refer to [3.-(3)-2) Needle entryin the needle slot of the feeddog in the lateral direction].

32’ At that time, fluctuate theneedle bar connecting rod to the right or left until theneedle bar connecting rod is approximately placed at thecenter of the play, and fastenthe clamping screw.

– 10 –

Standard Adjustment

2) Needle entry in the needle slot of the feed dog in feeding direction (LU-2210N/W-7, 2260N-W-7, 2212N-7)

• Needle Entry PointThe center of the needle slot in the feed dog must align thecenter of the needle .(For the 2-needle type, both the two needles should be applied).

• Requirements:• The needle bar should be brought to the lowest dead point.• The stitch dial should be set to [0] on the scale.• The needle feeding arm should be made perpendicular.• The following clearance should be provided between operator’s

side end of the slot in the throat plate and the edge of the feeddog .5.7 ± 0.2 mm → LU-2210N/W-7, LU-2212N-74.2 ± 0.2 mm → LU-2260N/W-7 (For all gauge sizes)

Needle bar frame driving link

90°

Needle feeding arm

LU-2260N/W-7 LU-2210N/W-7,LU-2212N-7

Throatplate

4.2±0.2mm

0.5mm 0.5mm 0.5mm

5.7±0.2mm

Operator’s direction

– 11 –


1. Set the stitch dial to [0] on the scale.2. Loosen the aperture plate set screw .3. Remove the aperture plate .4. Loosen the clamping screw of the needle bar connecting rod.5. Bring the needle bar to the lowest position of its stroke.6. Align the center of the needle with the center of the feed dog .7. Fasten the set screw of the needle bar connecting rod.(Cautions) Fasten the set screw with a tightening torque of 7.84 to

8.82N•m (80 to 90 kgf•cm).8. Raise the presser bar lifting lever.9. Insert the hinge screw of the presser bar lifting cylinder into

the forked section of the presser lifting lever .10. Make sure that the bottom face of the knee lifter arm A is en-

gaged with the presser lifting lever .11. Attach the aperture plate in place.(Caution) The feed amount of the needle is mechanically larger

than the feed amount of the feed dog by 5%.

o If the needle entry is adjusted tooclose to the operator:

1) The needle may interfere withthe feed dog , resulting inneedle breakage.

o If the needle entry is adjusted toofar from the operator:

1) When the needle comes out ofthe slot in the throat plate, theneedle may interfere with thefeed dog , resulting in threadbreakage.

2) The needle may come in con-tact with the feed dog duringthe reverse feed stitching, result-ing in needle breakage.

2’ For how to remove the apertureplate in LU-2212N-7, refer to [3.-(17) Aperture Plate RemovalProcedure].

7’ At that time, move the needle barconnecting rod to the right orleft until the needle bar connect-ing rod is positioned approxi-mately at the center of the play.If the needle bar connecting rodis not correctly positioned, an ex-cessive torque may result.

11’ For how to attach the apertureplate in LU-2212N-7, refer to [3.-(17) Aperture Plate RemovalProcedure].

– 12 –

10.2±0.1mm

Operator’s side

0.5mm 0.5mm

B

A

Standard Adjustment

3) Needle entry in the needle slot of the feed dog in feeding direction (LU-2220N-7)

• Needle Entry PointPosition where the distance between presser bar and upperfeed bar becomes 10.2 ± 0.1mm.

• Requirements:• Hand wheel graduation [A] coincides with the upper surface of

hand wheel indicator .• Standard feed dial graduation [0]• The needle feed arm is positioned perpendicular.

Needle bar frame driving link

90°

Needle feeding arm

– 13 –


1. Set the stitch dial to [0] on the scale.2. Loosen the aperture plate set screw .3. Let the hand wheel graduation [A] coincide with the upper surface

of hand wheel indicator .4. Loosen the clamping screw of the needle bar connecting rod.5. Adjust the distance between presser bar and upper feed bar

to 10.2 ± 0.1mm and tighten setscrew of the needle bar rockinglever.(At that time, the presser assumes the state of lowering. Themeasuring position of 10.2 ± 0.1mm is based on the height of thebottom surface of presser bar lower metal .

(Cautions) Fasten the set screw with a tightening torque of 7.84 to8.82N•m (80 to 90 kgf•cm).

6. Adjust feed dog so that the needle center coincides with thecenter of the feed dog hole.

7. Raise the presser bar lifting lever.8. Insert the hinge screw of the presser bar lifting cylinder into

the forked section of the presser lifting lever .9. Make sure that the bottom face of the knee lifter arm A is en-

gaged with the presser lifting lever .10. Attach the aperture plate in place.(Caution) The feed amount of the needle is mechanically larger

than the feed amount of the feed dog by 5%.

o If the needle entry is adjusted tooclose to the operator:

1) The needle may interfere withthe feed dog , resulting inneedle breakage.

o If the needle entry is adjusted toofar from the operator:

1) When the needle comes out ofthe slot in the throat plate, theneedle may interfere with thefeed dog , resulting in threadbreakage.

2) The needle may come in con-tact with the feed dog duringthe reverse feed stitching, result-ing in needle breakage.

2’ For how to remove the apertureplate in LU-2220N-7, refer to [3.-(18) Aperture Plate RemovalProcedure].

5’ At that time, move the needle barconnecting rod to the right orleft until the needle bar connect-ing rod is positioned approxi-mately at the center of the play.If the needle bar connecting rodis not correctly positioned, an ex-cessive torque may result.

10’For how to attach the apertureplate, refer to [3.-(18) AperturePlate Removal Procedure].

– 14 –

(4) Needle-to-Hook Relation

Standard Adjustment

1) Height of the Needle Bar

Requirements:The stitch dial should be set to [0].The needle bar should be brought to the low-est dead point.

Adjust the height of the needle bar so thata distance of 1.4 ± 0.2 mm will be providedbetween the top end of the needle eye andthe blade point of the hook when the needlebar is raised from its lowest dead point by 2.0± 0.2 mm.

Reference:The needle bar lowest dead point is wherethe lower face of needle bar frame isaligned with the upper marker line engravedon the needle bar.

2P stitch dial(For LU-2212N-7 and LU-2220N-7)

Blade point of the hookNeedle eyelet

2.0±0.2mm

1.4±0.2mm

Marker lines engraved on the needle bar

Aligned with the upper marker line engraved on the needle bar.

– 15 –


1. Set the stitch dial to [0] on the scale.2. Turn the hand-wheel to bring the needle bar to the lowest dead

point.3. Loosen the needle bar connecting stud clamping screw .4. Adjust the height of the needle bar to the specified dimension.5. Fasten the needle bar connecting stud clamping screw .

o Stitch skipping or thread breakagemay result.

4’ At that time, align the bottom faceof the needle bar frame withthe marker line engraved on theneedle bar (the upper one of thetwo marker lines). This will en-able you to adjust the height ofthe needle bar almost to thespecified dimension.

– 16 –

Standard Adjustment

2) Clearance between the Needle and the Blade Point of Hook

Gap between the needle and the hookblade point= 0.05 to 0.1 mmRequirements:• The timing between the needle and

the hook should be adjusted in ad-vance.

• Effective amount of the needleguard: 0.15 to 0.2 mm

• The stitch dial should be set to [0]on the scale.

Blade point of thehook

The needle guarddoes not work.

The needle guardworks.

Hook drivingshaft set collar

Hook d r i v i ngshaft coupling

Hook driving shaft

2.5±0.3mm

2.5±0.3mm

A

2.5±0.3mm

B C D

0.05 to 0.1mm

Blade point of thehook

Needle guard

0.15 to 0.2mm

Blade pointof the hook

0 to 0.05mm

(LU-2210N/W-7, LU-2260N/W-7 and LU-2212N-7) (LU-2220N-7)

– 17 –


1. Remove the throat plate.2. Set the stitch dial to [0] on the scale.3. Loosen the clamping screw of the hook driving shaft set collar.4. Slightly loosen the set screws and of the hook driving shaft

saddle.To loosen the hook shaft base mounting screw for the LU-2220N-7, loosen the setscrew and take out the thread trimmer air cylin-der mounting plate .To move the hook shaft base of the LU-2220N-7 to the right or left,remove three setscrews (hexagon socket head cap screws) andtake out the thread trimmer air cylinder together with the threadtrimmer air cylinder mounting plate . Since then, loosen the hookshaft base mounting screws and , and move the hook shaftbase to the right or left.

5. In the state that the needle holder is not effective, adjust the gap to0 to 0.05mm between the needle and the hook blade point.

6. Turn the eccentric pin of the hook driving shaft saddle with ascrewdriver to move the hook driving shaft saddle in the oppositedirection of the operator ( ) until it will go no further.

7. Fix the hook driving shaft saddle, holding it in the state describing instep 6, by fastening the set screws and in the hook drivingshaft saddle in the written order.

8. Turn the needle holder effectiveness adjusting screw and adjustthe effectiveness value to 0.15 to 0.2mm until the gap between theneedle and the hook blade point is adjusted to 0.05 ~ 0.1mm.

9. At this time, confirm that the clearances A , B , C and D in thehook driving shaft coupling are respectively adjusted to 2.5 ± 0.3mm.If not, adjust the clearances properly.

10.Confirm that the needle-to-hook timing is correct. If the timing iscorrect, fasten the clamping screw of the hook driving shaft setcollar. if not, refer to [(4)-3 Timing between the Needle and the Hook].When the gap between the needle and the hook blade point hasbeen adjusted for the LU-2220N-7 and timing for the needle andthe hook has been checked and adjusted, install the removed threadtrimmer air cylinder mounting plate on the hook shaft base.After the installation, it is necessary to readjust the thread trimmersystem.

o If the clearance between theneedle and the blade point of thehook is too large:Stitch skipping or improper thread-ing may result.

o If the clearance between theneedle and the blade point of thehook is too small:The needle may interfere with theblade point of the hook. As a re-sult, the blade point of the hookmay be damaged and threadbreakage may be caused.

– 18 –

Standard Adjustment

3) Timing between the Needle and the Hook

Align the center of the needle with the bladepoint of the hook.

Requirements:• The hand-wheel pointer should point

Graduation [L] on the hand-wheel.• The stitch dial should be set to [0] on the

scale.• The adjustment should be performed after

the needle bar has been adjusted to thecorrect height.

Graduation [L] on the hand-wheel

Pointer on thehand-wheel

Hand-wheel

Reverse feed lever

(1.4±0.2mm)

(2.0±0.2mm)

Blade point of the hook

Center of the needle

Lower shaft

Lower shaft coupling

L

– 19 –


1. Set the stitch dial to [0] on the scale.2. Loosen the set screw of the set collar of the hook driving shaft.3. Align the hand-wheel pointer with Graduation [L].4. Turn the hook in the normal direction until the blade point of the hook

is aligned with the center of the needle.5. Fasten the set screw .(Caution) Adjust the needle entry in the needle slot of the feed

dog with reference to the feeding direction prior to theadjustment of “Timing between the needle and thehook”.

o Loose stitches, stitch skipping orthread breakage may result.

3’ Refer to [3-(1) Types and Namesof Graduations on the Hand-wheel].

5’ Hold the hook by hand at the cor-rect position to maintain accurateneedle-to-hook timing and fastenthe set screw .

– 20 –

(5) Clearance between the Throat Plate and the Inner Hook Stopper

Standard Adjustment

o Hook Shaft Thrust Plate

Thickness (mm) Part No. Engraved mark

1.4 10111201 4

1.5 10109809 5

1.6 (Standard) 10112506 6

1.7 10112605 7

1.8 10112704 8

0.9±0.1mm Throat plate

Inner hook stopper

Inner hook stopper

Hook shaft bearing

Direction of rotation

– 21 –


1. Select an appropriate thrust plate of the hook shaft and adjust theclearance at the thrust plate.

2. Set the hook over the hook shaft while pressing the hook downto prevent any axial play.When fastening the set screws of the hook, first fasten the setscrew No. 1, by reference to the direction of rotation, of screws onthe flat section of the hook shaft . Then, fasten the set screwNo. 2, in terms of the direction of rotation, of screws.

3. For how to adjust the thread trimmer after the completion of the ad-justment of the clearance between the throat plate and the inner hookstopper, refer to [3-(10), -(11) and -(12) Thread Trimmer Device].

o If the clearance between the throatplate and the inner hook stopperis too large:• The inner hook may come off

the throat plate.o If the clearance between the throat

plate and the inner hook stopperis too small:• Loose stitches (isolated idling

loops) may result.• The moving knife may interfere

with the hook at the time ofthread trimming.

– 22 –

(6) Timing of the Cloth Feed Action

Standard Adjustment

1) Horizontal Feed Timing

• Set the stitch dial to the maximum value on the scale.• Align the hand-wheel pointer with the graduation [B] on the handle-wheel. In this state, move the reverse

feed lever up and down until the feed dog does not move in the feeding direction. Then fasten the feedlock cam set screw .Reference:

• When the hand-wheel pointer is aligned to the graduation [B] on the hand-wheel, the set screw No. 1 (in terms of the direction of rotation) on the feed rock cam is nearly brought to the top.

2) Vertical Feed TimingAdjust so that the mark (marker dot engraved on the end face of the feed rock cam) on the feed rockcam is in line with the mark (marker dot engraved on the feed driving cam). Then, fasten the setscrew of the feed driving cam .

Graduation [B] on the hand-wheel

Pointer on the hand-wheel

B

1mm

Feed converter

The marker dot is engravedon the end face of the feedrock cam.

B

A

– 23 –


1) Horizontal Feed Cam Timing1. Loosen the set screws of the bed top cover.2. Remove the bed top cover .3. Loosen the horizontal feed cam setscrew .4. Observing the notch on the belt cover, turn the hand-wheel until

the hand-wheel pointer is aligned with the graduation [B] on the hand-wheel.

5. Turn the Horizontal Feed Cam while moving the reverse feedlever up and down until the feed dog will not fluctuate. Now fix thefeed rock cam.

6. A clearance of 1 mm should be provided between the end face of thefeed rock rod and the end face of the Horizontal Feed Cam .

7. Fasten the Horizontal Feed Cam set screw .(Cautions) 1. Take care not to allow any such foreign matter as a

screw to enter the bed tank.2. Adjust the timing within the range of ±5° from the

standard timing.3. After the feed rock timing has been adjusted, re-

adjust the feed driving timing.

2) Vertical Feed Timing1. Perform the adjustment after adjusting the Horizontal Feed Timing.2. Loosen the vertical feed cam set screw .3. Adjust so that the mark (marker dot engraved on the end face of

the Horizontal Feed Cam ) on the Horizontal Feed Cam is in linewith the mark (marker dot engraved on the Vertical Feed Cam

).(Cautions) 1. Take care not to allow any such foreign matter as a

screw to enter the bed tank.2. Adjust the timing within the range of ±5° from the

standard timing.

o Improper stitch length may resultwhen the machine is operated athigh-low speed.

o Thread tension may change fromthe correct one.

o Tightness of normal and reversestitches may be different fromeach other.

4’ Refer to [3-(1) Types and Namesof Graduations on the Hand-wheel].

5’ At that time, the first screw inrevolving direction of the horizon-tal feed cam , is positioned al-most upright.

o When the Horizontal Feed Cam is fixed after turning it toward

the operator (in the direction ofarrow A) from the standard ad-justment position, the HorizontalFeed Timing will be advanced.When the Horizontal Feed Camis fixed after turning it away fromthe operator (in the direction ofarrow B) from the standard ad-justment position, the HorizontalFeed Timing is retarded.

o Improper stitch length may resultwhen the machine is operated athigh/low speed.

o When the Vertical Feed Cam is fixed after turning it toward theoperator (in the direction of ar-row A) from the standard adjust-ment position, the feed drivingtiming will be advanced. Whenthe Vertical Feed Cam is fixed af-ter turning it away from the op-erator (in the direction of arrowB) from the standard adjustmentposition, the Vertical Feed Tim-ing is retarded.

– 24 –

Standard Adjustment

3) Upper Feed Timing

Set marker dot engraved on the periphery of the main shaft in line with the set screw No. 1 of theupper feed cam and fasten the set screws No. 1 and No. 2.

Main shaft

0.5mm

A

B

– 25 –


1. Loosen the top cover setscrew.2. Remove the top cover.3. Turn the hand-wheel to bring the marker dot engraved on the

periphery of the main shaft to the top.4. Loosen the No.1 set screw and No. 2 screw of the upper feed cam

.5. Align the marker dot engraved on the periphery of the main shaft

with the set screw No. 1 of the upper feed cam .6. Fasten the set screws No.1 and No. 2 of the upper feed cam .(Cautions) 1. Take care not to allow any foreign matter such as a

screw to enter the arm.2. Adjust the timing within the range of ±5° from the

standard timing.


o When the upper feed cam isturned toward the operator (in thedirection of arrow A), the upperfeed timing will be earlier than thestandard timing. When the upperfeed cam is turned away from theoperator (in the direction of ar-row B), the upper feed timing willbe retarded more than the stan-dard timing.

5’ At that time, make sure that theclearance of 0.5 mm is providedbetween the end face of the up-per eccentric rod and the endface of the periphery of the up-per feed cam .

– 26 –

Standard Adjustment

4) Height of the Feed Dog

Height of the feed dog: 0.5 to 0.6 mmRequirements:• Set the stitch dial to [6] on the scale.• Align the hand-wheel pointer with the

graduation [L] on the hand-wheel.

Throat plate 0.5 to 0.6mm

Graduation [L] on the hand-wheel

Hand-wheel pointer

Hand-wheel

L

Vertical feed arm

– 27 –


1. Set the stitch dial to [6] on the scale.2. Slightly loosen the clamping screw of the vertical feed arm.3. Align the hand-wheel pointer with the graduation [L] on the hand-

wheel.4. Adjust the height of the feed dog to 0.5 to 0.6 mm.5. Loosen the vertical feed arm tightening screw .(Caution) Fasten the clamping screw with a tightening torque of

5.88 to 6.86N•m (60 to 70 kgf•cm).

If the height of the feed dog is

excessive:o The material may be fed back-

ward in the normal feed mode.If the height of the feed dog is insuf-ficient:o The stitch length may become

shorter than the specified value.3’ Refer to [3.-(1) Types and Names

of Graduations on the Hand-wheel].

– 28 –

Standard Adjustment

5) Amount of alternating vertical movement of the walking foot and presser foot (Balance between thelifting amounts of the presser foot and walking foot)

Align the marker dot engraved on the topfeed arm with the graduation [L] on the hand-wheel. Then, fasten the upper feed camclamping screw .Requirements:• The dial for setting the amount of alternat-

ing vertical movement of the walking footand presser foot should be set to [1].

• The stitch dial should be set to the maxi-mum value on the scale.

• The sole of the presser foot should rest onthe throat plate.

• Make the walking foot come in contact withthe feed dog.

• The upper feed timing has already beenproperly adjusted before the adjustment ofthe amount of alternating vertical move-ment of the walking foot and presser foot.

Hand-wheel

Hand-wheel

Upper feed cam

Converting unit of amount of alternating vertical movement ofthe walking foot and presser foot

AB

– 29 –


1. Set the stitch dial to the maximum value on the scale.2. Set the dial for setting the amount of alternating vertical move-

ment of the walking foot and presser foot to [1] on the scale.3. Remove the rubber plug from the top cover.4. Loosen the upper feed cam clamping screw from the hole where

the rubber plug has been removed.5. Align the marker dot engraved on the top feed arm with the gradu-

ation [L] on the hand-wheel.6. In the state described in step 5., make the walking foot rest on the

feed dog and make the presser foot come in contact with the throatplate.

7. Fasten the upper feed cam clamping screw .


o The lifting amount of the presserfoot or the walking foot would bedecreased. As a result, the ma-terial may not be fed smoothly.

5’ If the graduations on the hand-wheel shift in the direction A fromthe marker dot , the liftingamount of the walking foot willdecrease and the lifting amountof the presser foot will increase.If the graduations on the hand-wheel shift in the direction B, theformer will increase and the lat-ter will decrease.

– 30 –

(7) Adjustment of the Feed Mechanism

Standard Adjustment

1) Zeroing of the feed adjusting mechanism

• Align the feed adjusting pin with the sec-tion A of the feed adjusting belt .

• Make sure that the marking on the feed ad-justing eccentric pin faces in the samedirection as the slot in the feed adjustmentchange arm .

• Tilt the feed change belt in the directionof C or D until the feed amount of the feeddog becomes zero (0). At that position, fas-ten the set screw .

• Align the marking of the face apertureplate on the front face of the machinewith [0] on the scale of the stitch dial .

Level H

Level L

Slot

Marking (chamfered)

Section A

– 31 –


1. Turn the stitch dial clockwise while moving the reverse feed lever up and down until the feed adjusting pin meets the section A

of the feed adjusting belt . At that time, the feed adjusting pin and the feed adjusting belt cannot be observed. The above-mentioned adjustment allows the operator to feel by hand that thereverse feed lever will no longer come down.

2. Make sure that the marking (chamfered) on the feed adjusting ec-centric pin faces in the same direction as the slot in the feedadjustment change arm .

3. Loosen the drain cock and expel the oil from the drain opening.4. Remove the top cover of the bed.5. Loosen the set screw of the feed adjustment change arm .6. Turn the hand-wheel in the normal direction of rotation to adjust the

feed change belt so that the feed amount of the feed dog is setto zero (0).

7. Fasten the clamping screw in the feed adjustment change arm.

(Caution) Fasten the screw with a tightening torque of 3.43 to4.41N•m (35 to 45 kgf•cm).

8. Supply oil to the machine. (Check it through the oil sight window.)

9. Loosen the set screw of the stitch dial .10. Align zero (0) on the scale of the stitch dial with the marking

on feed aperture plate of the front face of the machine.11. Fasten the set screw of the stitch dial .

o The actual stitch length willgreatly differ from the value seton the stitch dial .

6’ When the feed change belt istilted in the direction of arrow C,the feeding amount in the nor-mal direction will increase. Whenthe feed crank stud is tilted in thedirection of arrow D, the feedingamount in the reverse directionwill increase.

8’ Supply oil from the oil port while checking the oil levelthrough the oil sight window .The amount of oil is sufficientwhen level H is reached.

11’ At that time, take care not to al-low the marking to shift fromthe zero (0) point on the scale ofthe stitch dial .

– 32 –

Standard Adjustment

2) Stitch length in the normal feed and reverse feed

Stitch length will change in accordance with the positions of the marking (chamfered section) of the feedadjusting eccentric pin with respect to the slot in the feed adjusting change arm as described below:• If the marking is tilted in the direction of arrow A .......... The stitch length of the normal feed stitching will

decrease.The stitch length of the reverse feed stitchingwill increase.

• If the marking is tilted in the direction of arrow B .......... The stitch length for the normal feed stitchingwill increase.The stitch length of the reverse feed stitchingwill decrease.

Marking (chamfered)

Slot

A

B

To improve ease of operation, set thestitch dial to the maximum valueon the scale before loosening the setscrew .

– 33 –


1. Set the stitch dial to the maximum value on the scale.2. Lower the reverse feed lever .3. Slightly loosen the set screw of the feed adjusting eccentric pin

.4. Set the stitch dial to [0] on the scale.5. Make the marking (chamfered section) of the feed adjusting eccen-

tric pin in the direction of the slot in the feed adjustment changearm .

6. In the state of step 5., fasten the set screw .[Confirmation]After the completion of adjustments, try to perform sewing workactually and examine how are the forward and reverse sewingpitches. Make fine adjustments of the marking (chamfering)position for the feed adjusting eccentric pin .

o The stitch length specified maynot be equally obtained in thenormal feed stitching and thereverse feed stitching, resultingin excessive stitch length errorbetween the normal feedstitching and the reverse feedstitching.

5’ Turning the feed adjusting ec-centric pin downward (in thedirection of arrow A) decreasesthe stitch length for the normalfeed stitching and increases thestitch length for the reverse feedstitching.Turning the feed adjusting ec-centric pin upward (in the direc-tion of arrow B) increases thestitch length for the normal feedstitching and decreases the stitchlength for the reverse feed stitch-ing.

o The machine has been factory-adjusted so that stitch length er-ror in the normal/reverse feedstitching does not exceed ± 10%of the specified value when thestitch dial is set to [6] on thescale.

– 34 –

3) 2P Adjustment (for LU-2212N-7 and LU-2220N-7)How to zero for the 2P adjustment

Standard Adjustment

Point zero (Origin) position

To be matched

Fig. A

Fig. B

Fig. C

LU-2212N-7

LU-2220N-7

– 35 –

1. Remove the belt from the hand-wheel on the machine head.2. Remove the pulley cover from the motor, and then, remove the

belt.3. Turn ON the power switch.4. Set the stitch dial to the maximum value (P=9) on the scale.5. Turn the 2P stitch dial counterclockwise and remove the 2P stitch

dial screw .6. Turn ON the 2P switch .

(The air cylinder will work so that the relationship between the 2Pfeed regulator and feed adjusting pin roller is set as shown inFig. A).

7. Lower the reverse feed lever so that the cam section (point zeroposition) of the 2P feed regulator is aligned with the feed adjust-ing pin roller ) (Fig. B).At that time, the reverse feed connecting arm is fixed as shownin Fig. C.

8. Turn the 2P stitch dial clockwise slowly until a slight load is felt(easily sensed by hand), to align the 2P stitch dial screw with the2P feed regulator . At that time, if the dial stopper on the 2Pstitch dial is matched with the stitch dial pin and the dial cannot be turned any more, loosen the 2P stitch dial set screw andadjust the dial position. In the case of adjusting the dial position,adjust it so that around the front or back where the 2P stitch dialadjusting screw is aligned with the 2P feed regulator , the dialstopper does not match with the stitch dial pin .

(Caution) If the 2P stitch dial is forcibly turned, after the 2Pstitch dial screw is aligned with the 2P feed regula-tor , the point zero position for the 2P adjustmentwould be shifted.

9. Loosen the 2P stitch dial set screw .10. Turn the 2P stitch dial counterclockwise to align with the dial

stopper position.11. Fasten 2P stitch dial setscrew .

[Confirmation]1. Perform the above adjusting procedure steps No. 1. through

4.2. Turn the 2P stitch dial counterclockwise and set it at where

it stops (at where it is stopped with the dial stopper ).3. Turn on the 2P switch .4. Perform the above adjusting procedure step No. 7. and align

the cam section (point zero position) of the 2P feed regulator with the feed adjusting pin roller . Then, when the hand-

wheel is turned and the stitch length set to zero, the 2P stitchdial point zero setting will have been completed. If it is not (ifthe stitch length is not set to zero), perform the adjustmentagain.

(Caution) 1. When you turn the 2P feed control dial , confirmwithout fail that the 2P switch is set at OFF.

2. Graduation 3 or below (where it stops with the dialstopper ) of the 2P feed control dial is used forthe calibration of the 2P feed control dial .Therefore, it cannot be used for actual sewing work.

3’ In some motor versions analarm might sound becausethey are not equipped with beltand alarm output. However, thealarm will be stop after someseconds so that, then, continuethe procedure.

10’ For the 2P stitch dial , the po-sition where it is stopped withthe dial stopper , is the pointzero position in the adjustment.


– 36 –

(8) Position of the Reverse Feed Connecting Arm/the amount of condensation

Requirement:• The stitch dial should be set to the maxi-

mum value on the scale.

Standard Adjustment0.

5 to

1.5

mm

11.5±0.5mm

(LU-2210N/W-7, LU-2260N/W-7 and LU-2212N-7) (LU-2220N-7)

[Sta

ndar

d: 1

2mm

]

– 37 –

Reverse Feed Lever Position Adjustment1. Set the stitch dial to the maximum value on the scale.2. Fasten the clamping screw of the reverse feed connection arm.3. Adjust so that the clearance of 0.5 to 1.5 mm is provided between the

reverse feed lever and the stopper when the reverse lever is slightly pressed down. Then, fasten the clamping screw .

(Caution) For a sewing machine equipped with the touch-backmechanism, a clearance of 11.5 ± 0.5 mm should beprovided between the top end of the rod of the reversefeed cylinder and the reverse feed cylinder knucklejoint . (12 ± 0.5mm for the LU-2220N-7)Fasten the locknut securely in the reverse feed cyl-inder knuckle joint .

Adjustment of condensation amount at thread trimming(LU-2220N-7)1. Loosen the fixing nut of the reverse cylinder knuckle joint .2. Adjust the gap between the rod tip of the reverse cylinder and the

reverse cylinder knuckle joint . (Turn the rod tip of the reversecylinder .)o Reduce it by 12mm or more. → The amount of condensation is

reduced.o Increase it by 12mm or more. → The amount of condensation is

increased.3. After adjustments, tighten the fixing nut .4. After the adjustment of the amount of condensation, check the position

of the reverse feed lever.

(Caution) When the amount of condensation is reduced, theresidual thread length on cloth side becomes shorter.However, if this amount is too small, the material clothmay be torn according to the stitch length. Such aninadequate setting can result in stitch skipping or threadbreakage.On the other hand, too much condensation can giverise to defective thread spreading, finally leading tothread breakage.The recommendable amount of condensation is 1.5 to2.0mm.

If the clearance between the stopperand the reverse feed lever is toolarge:o The top end of the reverse feed

lever will interfere with the bed.As a result, the stitch length for thereverse feed stitching may beshortened.

If the clearance between the stopperand the reverse feed lever is toosmall:o The reverse feed lever will in-

terfere with the stopper . As aresult, stitch length for the normalfeed stitching may be shortened.


– 38 –

(9) Bobbin Winder

A : 0.3 to 0.6 (mm)

B : 25.5±0.5 (mm)

Note that A and B are in the reset state.

(Caution) The above figure is illustrated as seen fromthe rear side of the machine head with theface aperture plate on the front of themachine head removed.

A

Bobbin winder

unit is in th

e re-

set s

tate

Bobbin winder unit isin the set state.

Bobbin presser spring

B

Standard Adjustment

– 39 –

1) Bobbin Winder Friction Wheel Adjustment1. Loosen the reverse feed cylinder set screw. (Except for LU-2212N-7

and LU-2220N-7)2. Remove the reverse feed cylinder. (Except for LU-2212N-7 and LU-

2220N-7)3. Remove the side plate.4. Set the bobbin winder in the reset state.5. Loosen the screw No. 1 in the bobbin winder friction wheel .6. Adjust the clearance A between the bobbin winder friction wheel

and the friction ring to 0.3 to 0.6 mm.7. Fasten the set screw of the bobbin winder friction wheel .8. Set the bobbin winder in the operating position and make sure that

the bobbin winder shaft rotates normally.9. Attach the aperture plate in place.

2) Bobbin Winding Amount Adjustment1. Loosen the face aperture plate set screw on the front of the ma-

chine head.2. Remove the face aperture plate on the front of the machine head.3. Loosen the set screw of the bobbin winder cam .4. Adjust the distance B from the bobbin winder shaft to the bobbin

presser to 25.5 ± 0.5 mm.5. Fasten the set screw of the bobbin winder cam .6. Attach the face aperture plate to the front of the machine head.7. Operate the sewing machine to perform bobbin winding.8. Securely fasten the hexagon nut .

3’ For how to remove the apertureplate of LU-2212N-7 and LU-2220N-7, refer to [(17) and (18)Ape r t u re P la te Remova lProcedure (for LU-2212N-7 andLU-2220N-7)].

8’ If the bobbin winder fails to ro-tate normally, finely adjust theclearance between the bobbinwinder friction wheel and thefriction ring .

9’ Attach the aperture plate refer-ring to step 8 to 11. in [3.-(3)-2)Needle entry in the needle slotof the feed dog in feeding direc-tion].

2’ For LU-2212N-7 and LU-2220N-7, remove the face aperture plate(A) on the front of the ma-chine head.

6’ For LU-2212N-7 and LU-2220N-7, attach the face aperture plateA on the front of the machinehead.

7’ Adjust so that the bobbin iswound with thread up to approxi-mately 90% of its capacity (diam-eter of the bobbin wound withthread: 23.3 mm) by turning thebobbin winding amount adjustingscrew .


– 40 –

0.2mm

1) Counter Knife

2) Clamp Spring

3) Knife Pressure

4) Moving Knife Driving Arms A, B and C

(10) Thread Trimmer Device (for LU-2210N/W-7 and LU-2260N/W-7)

5.5

to 6

.5m

m

23.6

mm

A

B

Model Dimension A (mm)

LU-2210N-7

LU-2260N-7

LU-2210W-7

LU-2260W-75.2

4.8

1.5 to 1.7mm

0.5mm

E

F

A

D

C

B

Counter knife gauge

23.6mm

Throat plate

1.5 to 1.7mm

A

B

Standard Adjustment

– 41 –

1) Counter Knife1. Loosen the set screws of the counter knife base .2. Bring the counter knife to the position shown in the left figure,

using the counter knife gauge supplied with the machine. At thattime, adjust the counter knife gauge so that the section A of thecounter knife gauge should come in contact with the attachinggroove on the bed slide plate, and the section B should come incontact with the end face of the throat plate.

3. Move the counter knife gauge base to adjust so that the counterknife comes in contact with the sections C and D of the counterknife gauge . Then, fasten the set screws .

2) Clamp Spring1. Loosen the set screws of the clamp spring .2. Adjust the clearance between the clamp spring and the counter

knife by sliding the clamp spring along the surface of the counterknife base on which the clamp spring is to be attached. At thistime, adjust the clearance using the sections E and F of the counterknife gauge .

3. Thickness of the section E is 1.7 mm and that of section F is 1.5 mm.Adjust the position of the clamp spring so that the section E of thegauge does not smoothly pass through the clearance provided be-tween the clamp spring and the counter knife , but the section Fof the gauge does smoothly pass through it.

4. Fasten the set screws of the clamp spring .

3) Knife Pressure1. When the moving knife and the counter knife come in contact

each other, adjust the attaching position of the moving knife sothat the moving knife starts coming in contact with the counterknife at the position that is 5.5 to 6.5 mm away from the top end ofthe moving knife , by means of loosing the set screw of themoving knife .

4) Moving Knife Driving Arms A, B and C1. In the case of the right-hand side hook, loosen the set screws of the

moving knife driving arm A and B and adjust so that the topend of the moving knife is 0.5 mm from the top end of the counterknife. In the case of the left-hand side hook, loosen the set screws ofthe moving knife driving arms A and C , and adjust in the sameway as in the right-hand side hook.

2. Put the plunger stopper of the thread trimmer solenoid ontothe main body of the solenoid and fasten the clamping screws ofthe moving knife driving arms B and C .

3. Adjust so that a clearance of 0.2 mm is provided between the threadtrimmer cam and the thread trimmer cam roller when the threadtrimmer cam is brought to the highest position of its stroke (forboth the right-hand and left-hand side hooks).

4. Fasten the clamping screw of the moving knife driving arm A .

[Item to be confirmed]Turn the hand-wheel by hand to make the sewing machine perform threadtrimming and align the top end of the moving knife with the top end of thecounter knife , which is the initial position of the thread trimming mechanism.At this time, make sure that a clearance of 0.05 to 1.5 mm is provided betweenthe plunger stopper of the thread trimmer solenoid and the main body ofthe thread trimmer solenoid .

o If the dimension A is larger:• Knife pressure will be higher. As a

r e s u l t , t h e m o t o r m a y b eunnecessarily stopped.

o If the dimension A is smaller:• Knife pressure will be lower, result-

ing in thread breakage.o If the dimension B (23.6 mm) is

larger:• The length of the bobbin thread to

be clamped will be shortened, re-sulting in stitch skipping.

o If the dimension B (23.6 mm) issmaller:• Thread trimming failure may occur.

o If the clearance between the clampspring and the counter knife is toolarge:• Bobbin thread clamping failure may

result.o If the clearance between the clamp

spring and the counter knife is toosmall:• The clamp spring may clamp the

needle thread. This means that thematerial may not be taken out fromthe sewing position with ease. As aresult, the clamped bobbin threadmay be removed together with thematerial.

o If the knife pressure is too high:• The blades of the counter knife

and the moving knife may break.o If the knife pressure is too low:

• Thread trimming failure may result.

o If the distance from the top end of thecounter knife to the top end of themoving knife is larger than the speci-fied value:• The moving knife may overrun

after trimming the thread, resultingin clamping failure.

o If the distance from the top end of thecounter knife to the top end of themoving knife is smaller than the speci-fied value:• The main body of the solenoid

may interfere with the plungerstopper at the time of thread trim-ming.


– 42 –

1) Positions of Counter Knife and Clamp Spring2) Counter Knife Base Position

3) Knife Pressure

4) Moving Knife Driving Arms A, B and C

(11) Thread Trimmer Device (for LU-2212N-7)

0.5±

0.1m

m

Counter knifeblade tip

Standard initial position

Initial position for thick thread

Align the end of the counter knifebase with the end of the counterknife gauge.

Standard Adjustment

4.1±0.1mm

A Attach the counter knife and clamp screw while they are contacted onto the stagedsection of the counter knife base.

0.2mm

17.5

mm

0

– 0.

2

Bed slide plate groove end

Throat plate

33±0

.1m

m

1 mm 0– 0.1

6 to

7m

m

– 43 –

1) Positions of Counter Knife and Clamp Spring1. Loosen the set screws of the counter knife .2. Bring the top end of the counter knife so that it comes in contact with the staged section of

the counter knife base .3. Adjust so that the distance between the end of the counter knife base and the top end of the

counter knife reaches 17.5 mm.4. Fasten the set screws of the counter knife .Clamp Spring Position1. Loosen the set screws of the clamp spring .2. Bring the end of the clamp spring so that it comes in contact with the staged section of the

counter knife base .3. While the end of the clamp spring comes in contact with the staged section of the counter knife

base, slide the end of the clamp spring and adjust so that the distance between the clampspring and the counter knife reaches 4.1 ± 0.1 mm.

4. Fasten the set screws of the clamp spring .(Caution) When the positions of the counter knife and the clamp spring are

moved, re-adjust the counter knife base position and knife pressure.

2) Counter Knife Base Position1. Loosen the set screws of the counter knife base .2. Move the counter knife base to the position specified in the figure using the counter knife

gauge supplied with the machine.3. Fasten the set screws of the counter knife base .(Caution) When the counter knife base is moved, re-adjust the knife pressure.

3) Knife Pressure1. Adjust, when the moving knife and the counter knife come in contact with each other, the

attaching position of the moving knife so that the moving knife starts coming in contact withthe counter knife at the position that is 6 to 7 mm away from the top of the moving knife .At this time, perform aforementioned adjustment after loosening the set screws of the mov-ing knife .

4) Moving Knife Driving Arms A, B and C1. Loosen the moving knife driving arms A and B and adjust so that the distance between

the top end of the counter knife and the top end of the moving knife becomes 0.5 mm. Inthe case that a bobbin thread clamp failure occurs when using a thick thread, agree the top endof the counter knife with the top end of the moving knife .

2. Put the plunger stopper of the thread trimmer solenoid onto the main body of the solenoid and fasten the clamping screws of the moving knife driving arms B and C .

3. Adjust so that a clearance of 0.2 mm is provided between the thread trimmer cam and thethread trimmer cam roller when the thread trimmer cam is brought to the highest positionof its stroke (for both the right-hand and left-hand sides).

4. Fasten the clamping screw of the moving knife driving arm A .[Item to be confirmed]Turn the hand-wheel by hand to make the sewing machine perform thread trimming and align the top endof the moving knife with the top end of the counter knife . This is the initial position of the threadtrimming mechanism. At this time, confirm that a clearance of 0.05 to 0.15 mm is provided between theplunger stopper of the thread trimmer solenoid and the main body of the thread trimmer solenoid .

o If the distance (17.5 mm) from the top end of thecounter knife base to the top end of the counterknife is larger than the specified value:• The length of bobbin thread to be clamped will

be shortened, resulting in stitch skipping.• The bobbin can not be inserted or removed.

o If the distance (17.5 mm) from the top end of thecounter knife base to the top end of the counterknife is smaller than the specified value:• Thread trimming failure may be caused.

o If the distance (4 mm) from the counter knife to theclamp spring is larger than the specified value:• Bobbin thread clamping failure may be caused.• Stitch skipping may be caused at the sewing start.

o If the distance (4 mm) from the counter knife to theclamp spring is smaller than the specified value:• The clamp spring may clamp the needle thread.

This means that the material may not be takenout from the sewing position with ease. As a re-sult, the bobbin thread clamped may be removedtogether with the material.

• The clamp spring may interfere with the rearend of the moving knife , resulting in deforma-tion of the clamp spring.

o If the distance (1 mm) from the throat plate to thecounter knife is larger than the specified value:• The knife pressure may increase, resulting in

motor stop.o If the distance (1 mm) from the throat plate and the

counter knife is smaller than the specified value:• The knife pressure may decrease, resulting in

thread trimming failure.o If the distance (33 mm) from the bed slide plate

end surface to the top end of the counter knife islarger than the specified value:• The length of bobbin thread to be clamped will

be shortened, resulting in stitch skipping.o If the distance (33 mm) from the bed slide plate

end surface to the top end of the counter knife issmaller than the specified value:• Thread trimming failure may result.

o If the knife pressure is too high:• The counter knife blade and the moving knife

blade may break.o If the knife pressure is too low:

• Thread trimming failure may result.

o If the distance from the top end of the counter knifeto the top end of the moving knife is larger than thespecified value:• The moving knife may overrun after trimming

the thread, resulting in clamping failure.o If the distance from the top end of the counter knife

to the top end of the moving knife is smaller thanthe specified value:• The main body of the thread trimmer solenoid

may come in contact with the plunger stopper at the time of thread trimming.


0– 0.2

– 44 –

Twist the leadby one turn.

5) Height of the Moving Knife (LU-2210N/W-7, LU-2212N-7 and LU-2260N/W-7)(for the right-hand side hook)

0.3 to 0.4mm (LU-2212N-7)0.4 to 0.5mm (LU-2210N/W-7/LU-2260N/W-7)

Standard Adjustment

Thread trimmer cam

– 45 –

Height of the Moving Knife (for the right-hand side hook)1. Disconnect the lead wire of the thread trimmer solenoid from

the terminal board .2. Loosen the clamping screw in the hook driving shaft set collar.3. Disconnect the urethane tubes from the tube connecting screws

of the hook driving shaft saddle.4. Loosen the hook driving shaft saddle set screw and remove the

hook driving shaft saddle.5. Loosen the thrust collar set screws for the moving knife .6. Loosen the set screw of the moving knife driving arm A .7. Loosen the set screw of the moving knife driving arm B .8. Adjust so that a clearance of 0.4 to 0.5 mm is provided between the

moving knife and the inner hook by moving the moving knifeshaft up and down. (For LU-2210N/W and LU-2260N/W)

9. Fasten the moving knife thrust collar set screw .10. Adjust the moving knife driving arm A and fasten the set screw

. (Refer to [3.-(10)-4 Moving Knife Driving Arms A, B and C]).11. Adjust the moving knife driving arm B and fasten the set screw

. (Refer to [3.-(10)-4 Moving Knife Driving Arms A, B and C]).12. Temporarily fix the hook driving shaft saddle.13. Connect the lead wire of the thread trimmer solenoid to the

terminal board .14. Connect the urethane tubes to the tube connecting screws of

the hook shaft saddle. At the same time, use the tube connectingscrews to which the urethane tubes had been connected be-fore removing it.

15. Adjust the clearance between the needle and the blade point of thehook.(Refer to [3.-(4)-2) Clearance between the Needle and the BladePoint of the Hook]).

16. Adjust the needle-to-hook timing. (Refer to [3.-(4)-3) Timing betweenthe Needle and the Hook]).

o If the clearance between themoving knife and the bobbin caseis too large:• The needle thread and bobbin

thread may fail to be caught bythe moving knife.

o If the clearance between the mov-ing knife and the bobbin case istoo small:• The moving knife may inter-

fere with the bobbin.• Widen the space in the hook

driving shaft coupling, then re-move the hook driving shaftsaddle.

o In the case of LU-2212N-7:8’ Adjust so that the clearance of

0.3 to 0.4 mm is provided be-tween the moving knife andthe inner hook by moving themoving knife shaft up anddown.

13’Give the lead wire a clockwiseturn and connect it to the termi-nal board while routing it alongthe back of the solenoid . Atthat time, take care not to allowthe lead to come in contact withthe plunger shaft .


– 46 –

6) Height of the Moving Knife (LU-2260N/W-7)(for the left-hand side hook)

0.4 to 0.5mm

Standard Adjustment

– 47 –

Height of the Moving Knife (for the left-hand side hook)1. Tilt the machine head.2. Loosen the set screws (two pcs.) of the moving knife shaft thrust

collar and the clamping screw of the moving knife driving armC .

3. Loosen the clamping screw of the moving knife driving arm A .4. Adjust so that a clearance of 0.4 to 0.5 mm is provided between the

moving knife and the inner hook , by moving the moving knifeshaft up and down.

5. Fasten the set screws (2 pcs.) of the moving knife shaft thrustcollar .

6. Fasten the clamping screw of the moving knife driving arm C and the clamping screw of the moving knife driving arm A .(Refer to [3.-(10)-4) Moving Knife Driving Arms A, B and C]).

o If the clearance between themoving knife and the bobbin caseis too large:• The needle thread and the bob-

bin thread may fail to be caughtby the knife.

o If the clearance between the mov-ing knife and the bobbin case istoo small:• The moving knife may inter-

fere with the bobbin.


– 48 –

7) Thread Trimmer Cam (for LU-2210N/W-7 and LU-2260N/W-7)

Thread eyelet of the moving knife

Thread(Tetron #8)

Front end of the moving knife

Graduation [D] on the Hand-wheel

Hand-wheel pointer

Reversedirection

Normaldirection

Standard Adjustment

– 49 –

1. Tilt the machine head and support the head at that position, usingthe head support bar.

2. Move the moving knife forward by hand until it will go no further.(While turning the hand-wheel by hand, draw the moving knife

forward from its initial position, and the moving knife will move).3. Put a thread (Tetron #8) into the thread eyelet of the moving knife

. (The thread should be held slack until the thread has beentrimmed).

4. Turn the hand-wheel slowly by hand in the normal direction ofrotation.

5. The moving knife engages with the counter knife and the threadis trimmed. Then, stop turning the hand-wheel .

6. Turn the hand-wheel slightly from the position described in step5. in the reverse direction of rotation. Turn it to the extent where thethread trimmer cam does not come in contact with the threadtrimmer cam roller .

7. Loosen the set screws (3 pcs.) of the thread trimmer cam .8. While securing the thread trimmer cam by hand so that it does

not come in contact with the moving knife driving arm A , turn thehand-wheel until the hand-wheel pointer meets the graduation[D] on the hand-wheel.

9. In the state described in step 8. turn the thread trimmer cam untilit slightly comes in contact with the thread trimmer cam roller ofthe moving knife driving arm A .

10. Fasten the set screw of the thread trimmer cam .11. Make sure that the timing of thread trimming action has been prop-

erly adjusted. Repeat steps 3. and 4. and perform thread trimming.Now, check that the hand-wheel pointer meets the graduation [D]on the hand-wheel: they will meet if the timing of thread trimmingaction has been properly adjusted.


o If the timing of thread trimming istoo early:• The length of thread remaining

at the needle after thread trim-ming will be insufficient. As a re-sult, the thread may slip out ofthe needle eyelet at the sewingstart or after thread trimming.

• Stitch skipping may occur at thestart of sewing.

o If the timing of thread trimming isto late:• Thread trimming failure may be

caused.8’ For the marker dot engraved on

the hand-wheel, refer to [3.-(1)Types and Names of Gradua-tions on the Hand-wheel].

– 50 –

8) Thread Trimmer Cam (for LU-2212N-7)

Graduation [J] on the hand-wheel

Hand-wheel pointer

Reversedirection

Normaldirection

J

Forwardingdirection

Section R

Standard Adjustment

– 51 –

1. Tilt the machine head and support the head using the head supportbar.

2. Align the hand-wheel pointer with the graduation [J] on the hand-wheel by turning the hand-wheel .

3. Move the moving knife forward so that the thread trimmer camroller comes in contact with the thread trimmer cam .

4. Loosen the thread trimmer cam set screw .5. Make the section R of the thread trimmer cam come in close contact

with the thread trimmer cam roller .6. Fasten the thread trimmer cam set screw .7. Make sure that the hand-wheel pointer meets the graduation [J] on

the hand-wheel when the section R of the thread trimmer cam comesin close contact with the thread trimmer cam roller.


2’ For the marker dot engraved onthe hand-wheel, refer to [3.-(1)T y p e s a n d N a m e s o fGraduations on the Hand-wheel].

– 52 –

* Before adjusting the area of the thread trimming device, remove covers (face plates (right, left, and front)plus auxiliary cover) from the top surface of the bed.Remove and remount the throat plate, as required.

* Adjustments of the thread trimming device shall be carried out according the sequential order instructed inthis manual.Otherwise, the result will be different from that of regular adjustments.

* Before the adjustment of the thread trimming device, check the mounting position of the feed dog.There are adjusting points according to the feed dog standard.[Refer to 3.-(3)-2) Needle entry in feeding direction in regard to the feed dog hole.]

1) Positioning for the thread trimming cylinder joint

7.0±0.5mm

(12) Thread Trimmer Device (LU-2220N-7)

Standard Adjustment

– 53 –

1. Loosen the fixing nut of the thread trimming cylinder joint.2. Adjust the size of the thread trimming cylinder joint and the thread

trimming cylinder to 7.0 ± 0.5mm.3. Tighten the fixing nut of the thread trimming cylinder joint.


– 54 –

2) Counter knife (adjustment of movement) (Positioning for the counter knife base stopper)

Contact

Grooves of face plates

Top surface ofthe bed.

9.0±0.5mm

37.8±0.1mm

37.8±0

.1m

mStandard Adjustment

– 55 –

1. Loosen the setscrew of the counter knife base stopper.2. Turn the hand wheel by hand and let the sewing machine fall down

according to the lower dead point of the thread take-up lever.3. Loosen the tightening screw of the counter knife driving arm.4. Adjust the distance to 37.8 ± 0.1mm between the tip of the counter

knife and the bed groove.(At that time, it is possible to use an accessory adjusting gauge.)If the counter knife is removed (for replacement, etc.), it shouldbe fixed around the center position within the adjusting range ofsetscrew oblong hole for the counter knife .Right and left positioning for the counter knife shall be adjustedseparately.

5. While the state of 4. above (37.8 ± 0.1mm) is maintained, keep acontact between the counter knife base and the counter knifebase stopper , and fix the counter knife base stopper .

6. While the state of 4. above (37.8 ± 0.1mm) is maintained, adjust thegap to 9.0 ± 0.5mm between the thread trimming cylinder joint and the joint stopper . (This shall be done manually.)(At that time, it is possible to use an accessory adjusting gauge.)

7. Tighten the tightening screw of the counter knife driving arm.At that time, keep pressing the counter knife driving arm upwards,and tighten the tightening screw of the counter knife driving armin order to remove thrust rattling in vertical directions.

8. Return the thread trimming cylinder joint by hand to the positionof the joint stopper and raise the sewing machine.

2.4 43.0

(t = 0.6)

29.0 26.8

37.8

9.0

Adjusting gauge (accessory)


– 56 –

3) Counter knife (adjustment of right and left positioning)

When mounting the counter knife , keepit pressed against the counter-worker sideand tighten the setscrew.

2.4±0.15mm

Standard Adjustment

– 57 –

1. After the adjustment of the feed dial to [0], turn the hand wheel byhand adjusted to the lower dead point of the thread take-up lever.

2. Actuate the [solenoid valve] manually and move the thread trimmingcylinder.Press the manual switch No. 3 of the [solenoid valve] to assume thelocked condition.[Refer to 3.- (12) –13) Description of the solenoid valve.]

3. Loosen the counter knife screw and move the counter knife tothe right and left so that the distance is adjusted to 2.4 ± 0.15mmbetween the left end of the feed dog and the thread guide . (Atthat time, it is possible to use an accessory adjusting gauge.)

4. Tighten the counter knife by means of the counter knife setscrew.

In this case, keep the counter knife lightly pressed against thecounter-worker side and tighten the counter knife setscrew .

5. Unlock the manual switch of the [solenoid valve] that has beenactuated.[Refer to 3.- (12) -13) Description of the solenoid valve.]

[Confirmation]After adjustments in regard to this item (right and left positioningfor the counter knife), manually actuate the [solenoid valve]([solenoid valve] No. 3 switch) and examine the following threepoints when the thread trimming cylinder is moved:1. Distance between tip of the counter knife: 37.8 ± 0.1mm2. Distance between cylinder joint and joint stopper: 9.0 ± 0.5mm3. Distance from left end of the feed dog to the thread guide: 2.4± 0.15mm



2.4 43.0

(t = 0.6)

29.0 26.8

37.8

9.0

– 58 –

4) Moving knife (adjustment of vertical positioning)

0.5 to 0.6mm

Coincidence with top surfaceof the moving knife

Standard Adjustment

5) Counter knife (adjustment of vertical positioning)

– 59 –

4) Moving knife (adjustment of vertical positioning)1. Let the sewing machine fall down and loosen the moving knife driving

arm tightening screw and the moving knife shaft thrust collarsetscrew .

2. Move the moving knife vertically so that the gap is adjusted to 0.5to 0.6mm between the bottom surface (rear side) of the throat plate

and the top surface of the moving knife .(At that time, it is possible to use an accessory adjusting gauge.)

3. Tighten the moving knife driving arm tightening screw and thethrust collar setscrew .When tightening the moving knife driving arm tightening screw ,follow the adjusting procedures of 7), 8), 9), and 10) to be describedlater.

5) Counter knife (adjustment of vertical positioning)1. Loosen the counter knife base tightening screw and let the upper

blade end of the counter knife coincide with the upper surface ofthe moving knife .(In this case, pay attention to hook’s blade point. Work can be donesafely if the main shaft angle is adjusted to the vicinity of the engravedmark line L.)

2. After adjustments, tighten the counter knife base tightening screw.

2.4 43.0

(t = 0.6)

29.0 26.8

37.8

9.0



– 60 –

6) Thread guide mounting position

Coincidence of upper surfacewith the moving knife

7) Adjustment of knife pressure

29 to

30m

m

Standard Adjustment

– 61 –

6) Thread guide mounting position1. Loosen the thread guide setscrew .2. Let the top surface of the thread guide coincide with that of the

moving knife and shift it fully in the direction of the arrow specifiedin the drawing.

3. Tighten the thread guide setscrew .

7) Adjustment of knife pressure1. Turn the hand wheel by hand and adjust it to the lower dead point of

the thread take-up lever. Let the sewing machine fall down.2. Actuate the [solenoid valve] manually and assume the state that the

thread trimming cylinder is pulled.Press the manual switch No. 3 of the [solenoid valve] to assume thelocked condition.[Refer to 3- (12) –13) Description of the solenoid valve.]

3. While the state of 2. above is maintained, slowly turn the hand wheelby hand and adjust the distance to 29 to 30mm between the R part ofthe moving knife and the end surface of the bed.(At that time, it is possible to use an accessory adjusting gauge.)

4. Loosen the moving knife setscrew and make the blade surface ofthe moving knife contact with the blade point of the counter knife

. Since then, tighten the moving knife setscrew again.5. Unlock the manual switch of the [solenoid valve] that has been actuated.

Turning the hand wheel slowly bay hand, take out the thread trimmingcam rollers from the cam groove of the thread trimming cam.

*1 : If the knife pressure seems to be weak, lightly press the movingknife against the counter knife at the time of adjustmentsaccording to 4. above and tighten the moving knife setscrew .If the knife pressure is excessive, this will result in abrasion ordestruction of the blade. For this reason, the knife pressure shouldbe adjusted to the least minimum level.

*2 : If the thread cannot be cut even with high knife pressure, readjustthe height of the moving knife or the counter knife within thepossible range until the blade surface can fit properly.Refer to 3-(12)-4) Moving knife (Adjustment of vertical positioning)and 3-(12)-5) Counter knife (Adjustment of vertical positioning).

*3 : After the adjustment of knife pressures, make readjustmentsaccording to 3-(12)-8) Moving knife driving arm and initial positionof the moving knife, 3-(12)-9) Adjustment of gap between themoving knife driving arm and the moving knife driving arm stopper,and 3-(12)-10) Mounting position of the moving knife return plate.

2.4 43.0



(t = 0.6)

29.0 26.8

37.8

9.0

– 62 –

8) Moving knife driving arm and initial position of the moving knife

Top surface of the bed

Cam groove

26.8

±0.1

mm

0.05 to 0.15mm

Outer periphery of thethread trimming cam

26.8±0.1mm

Face plate groove

Standard Adjustment

– 63 –

1. Let the sewing machine fall down and manually actuate the [solenoidvalve] in the state that no thread trimming cam roller is entered inthe cam groove. Assume the condition that the thread trimming aircylinder is protruded.(Press the manual switch No. 4 of the [solenoid valve] to assume thelocked state.)[Refer to 3- (12) –13) Description of the solenoid valve.]

2. Loosen the moving knife return plate setscrew and remove themoving knife return plate .

3. Loosen the moving knife driving arm stopper nut and then themoving knife driving arm stopper screw .

4. Loosen the moving knife driving arm tightening screw .5. Adjust the gap to 0.05 to 0.15mm between the thread trimming cam

roller and the outer periphery of the thread trimming cam. Then,adjust the moving knife to its initial position.The initial position of the moving knife is defined when the distanceis 26.8 ± 0.2mm between tip of the moving knife and the bedgroove. (At that time, it is possible to use an accessory adjustinggauge.)

6. While the state of 5. above is maintained, tighten the moving knifedriving arm tightening screw . (Tightening torque: 5.88 to 6.86N•m(60 to 70kgf•cm)) For the moving knife driving arm in verticaldirections at that time, the gap shall be 1.0 ± 0.2mm between bottomsurface of the moving knife driving arm and the top surface of thethread trimming cam.Subsequently, perform “9) Adjustment of gap between the movingknife driving arm and the moving knife driving arm stopper”.



2.4 43.0

(t = 0.6)

29.0 26.8

37.8

9.0

– 64 –

9) Adjustment of gap between the moving knife driving arm and the moving knife driving arm stopper

10) Mounting position of the moving knife return plate

The clearance between the movingknife drive arm stopper screw andthe moving knife drive arm stopper

shall be 0.05 to 0.1 mm.

The return pin and themoving knife return plate shall keep contact with eachother.

Hand wheelindicator

Hand wheelgraduations

Cam groove

Contact

(0.05 to 0.15mm)

0.05 to 0.1mm

Standard Adjustment

11) Adjustment of timing for the thread trimming cam

– 65 –

9) Adjustment of gap between the moving knife driving arm andthe moving knife driving arm stopper

1. While the state of 8), Moving knife driving arm and initial position ofthe moving knife, is maintained, tighten the moving knife driving armstopper screw .

2. Adjust the gap to 0.05 to 0.1mm between the moving knife drivingarm stopper screw and the moving knife stopper .

3. Tighten the moving knife driving arm stopper screw nut .

10) Mounting position of the moving knife return plate1. Keeping the gap as per 9) Adjustment of gap between the moving

knife driving arm and the moving knife driving arm stopper, make themoving knife return plate contact with the return pin .

2. Tighten the moving knife return plate setscrew . Unlock the manualswitch of the [solenoid valve] that has been actuated as per 3. herein.

(Caution) If a machine lock occurs in the middle of threadtrimming, confirm the adequacy of adjusting valuesspecified in 3.-(12)-8), 3.-(12)-9), and 3.-(12)-10).If any inadequacy is discovered, readjustments arerequired.

11) Adjustment of timing for the thread trimming cam1. Let the sewing machine fall down and loosen the thread trimming

cam setscrew .2. Turn the hand wheel by hand and let the hand wheel graduation [L]

coincide with the upper surface of the hand wheel indicator.3. Manually make the thread trimming cam roller come in contact

with the cam groove of the thread trimming cam .4. Making the thread trimming cam roller contact with the thread

trimming cam , turn the thread trimming cam so that the threadtrimming cam roller comes in contact with the starting R part ofthe cam groove.

5. Fix the thread trimming cam with the use of the thread trimmingcam setscrew .


– 66 –

12) Clamp spring mounting position

43.0

to 4

3.5m

m

Contact

When the moving knife advancesto the extreme far end, it shall notcontact the clamp spring .

43.0

to 4

3.5m

m

Standard Adjustment

– 67 –

1. When the moving knife stays in the initial position, loosen theclamp spring setscrew .(When removing the clamp spring setscrew completely, move themoving knife manually. While the hand wheel is turned by hand,the moving knife can be moved after passing the position of theengrave line L.)

2. Adjust the distance to 43.0 to 43.5mm between the clamp spring and the bed end.(At that time, it is possible to use an accessory adjusting gauge.)

3. Let the clamp spring come in contact with the moving knife and tighten the clamp spring setscrew .(Tightening torque: 0.2 to 0.3N•m (2 to 3kgf•cm))

* When using an optional clamp spring for thin threads, theadjusted value shall be 43.5mm so that the clamp spring ismade to contact the side surface of the moving knife strongly.

[Confirmation]Examine the following two points when the clamp spring is

mounted:1. No contact between the clamp spring and the hook2. No contact with the clamp spring when the moving knife

has advanced to the extreme far end

* If positioning for the clamp spring cannot be adjusted byloosening the clamp spring setscrew , try to loosen the clampspring base setscrew and move the clamp spring base foradjustments.(Vertical positioning for the clamp spring base is devisedbased on the attachment to the hook shaft base. Lightly pressingit downwards, tighten the setscrew .)


2.4 43.0

(t = 0.6)

29.0 26.8

37.8

9.0


– 68 –

B

C

[8]

13) Explanation of the solenoid valve

[9] [4] [2]

[B][C]

[7] [5] [3] [1]

Information about the solenoid valve manual switch

When the switch (in green) ispressed inside the cover, theso leno id va l ve can beoperated manually.

The switch can be locked by turningthe switch in the direction of the arrowwhile it is kept pressed.The switch can be unlocked by turningit in the opposite direction of the arrow.

Standard Adjustment

– 69 –

Function

[1] Condensation

[2] BT

[3] Thread trimmer (Cylinder pulled)

[4] Thread trimmer return (Cylinder protruded)

[5] Needle thread clamp (Cylinder protruded)

[7] AK (Presser foot raised)

[8] AK (Presser foot lowered)

[9] DL (Cylinder protruded)

[B], [C] 2P B , C

* When the power supply is turned ON, confirm that allsolenoid valve covers are closed.

In the state that the manual switch is locked,the covers cannot be closed. In other words,this method is effective in avoidingmisoperation of the solenoid valve.

Solenoid valve number (symbol)


– 70 –

Outer hookThroat plate

Backward end of the opener

Forward end of theopener

A

C

B

0.1 to 0.3mm

(13) Opener

1) Timing of the Opener

2) Clearance between the opener and the protruding section of the inner hook

Requirements:• The opener should be in its back-

ward position.• Press the stopper in the inner

hook stopper against the in-ner hook resting groove on thethroat plate.

Hand-wheel pointer

Graduation [J] on the hand-wheel

Throat plate

Backward endof the opener

Forward end ofthe opener

Retard Advance

Slot

Requirements:• For LU-2210N/W-7, LU-2212N-7 and

LU-2220N-7The opener should be brought to itsforward end when the hand-wheelpointer meets the graduation [J] on thehand-wheel.

• For LU-2260N/W-7The opener should be brought to itsforward end when the hand-wheelpointer meets the graduation [K] onthe hand-wheel.

Standard Adjustment

– 71 –

1) Timing Adjustment of the Opener1. Loosen the set screws (2 pcs.) of the opener shaft screw gear .2. For LU-2210N/W-7, LU-2212N-7 and LU-2220N-7: Align the hand-

wheel pointer with the graduation [J] on the hand-wheel.For LU-2260N/W-7: Align the hand-wheel pointer with the gradua-tion [K] on the hand-wheel.

3. Turn the opener shaft using the slot provided on the bottom end ofthe opener shaft .

4. For the standard adjustment turn the opener shaft so that theopener is brought to the forward end position in the state describedin item 2 . Then, fasten the set screws (2 pcs.) of the opener shaftscrew gear.

(Caution) Re-adjust the thread trimmer cam after the completionof the adjustment of the opener timing. (Refer to [3.-(11)-7) and 8) Thread Trimmer Cam and 3.-(12)-11) Ad-justment of timing for the thread trimming cam]).

2) Clearance between the Opener and the Protruding Section ofthe Inner Hook

1. Turn the hand-wheel to move the opener in the direction of arrowA. Then, loosen the opener set screw .

2. Turn the hand-wheel to move the opener in the direction of arrowB. Then, loosen the opener set screw . At that time, be sure toloosen the screw with the opener positioned at its backward end.

3. Turn the inner hook in the direction of arrow C, and press theinner hook stopper against the inner hook resting section ofthe throat plate.

4. Move the opener and adjust so that a clearance of 0.1 to 0.3 mm isprovided between the opener and the triangular projection of theinner hook.

5. Fasten the opener set screw .6. Turn the hand-wheel to move the opener in the direction of arrow

A. Then, fasten the opener set screw .


o Loose stitches may be caused.2’ Refer to [3.-(1) Types and

Names of Graduations on theHand-wheel].

4’ Fasten the opener shaft screwgear set screw while pressingthe opener from the upper sideand pressing upward the openershaft screw gear so as toeliminate a play.

• If the opener shaft is turned clock-wise as viewed from underside,the timing of the opener is ad-vanced. If the opener shaft isturned counterclockwise, it is re-tarded.

o If the clearance between theopener and the inner hook trian-gular projecting section of the in-ner hook is too large:• Loose stitches may be caused.

o If the clearance between theopener and the inner hook trian-gular projecting section of the in-ner hook is too small:• The inner hook may break.

– 72 –

(14) Presser Lifting Unit

1) Presser Lifting Amount

Standard Adjustment

Presser lifter camPresser lifter lever

2) Presser Lifting Cylinder

21.7 mm 0– 0.3

[As viewed from the Side 2]

Arm

Knee lifter spring

1mm

9.6 ± 1.8 mm(Manual operation)

Presser foot

Throat plate

15.5 mm(Automatic)

Presser foot

Throat plate

[As viewed from the Hand-wheel Side]

+1.0–0.8

+1.0–0.8

(10.

8mm

)

19m

m

*At the time when the presser foot is lifted by 15.5 mm

– 73 –

1) Presser Lifting Amount1. Remove the face plate and the aperture plate .2. Loosen the presser lifting bracket clamping screw and knee lifter

arm A clamping screw .3. Set the height of the presser foot to 15.5 mm.4. Position of the Knee Lifter Arm A

Lateral Direction: ......... The distance from the end face of the kneelifter arm A to the end face of the uppersprocket is 1 mm.

Vertical Direction: ........ The distance from the upper face of the kneelifter arm A to the center of the main shaft

is 19 mm.5. In the state in step 4. press the presser lifting bracket pin against

the presser lifting guide bracket , while the end face of the presserlifting bracket is put to the end face of the presser lifting guidebracket . In this state, fasten the presser lifting bracket clampingscrew .

2) Presser Lifting Cylinder1. Loosen the locknut of the cylinder connecting screw .2. Adjust so that the distance from the top end of the rod of the presser

lifting cylinder to the center of the cylinder connecting screw is21.7 mm.

3. Fasten the locknut of the cylinder connecting screw .(Caution) When mounting the window plate on the sewing ma-

chine for the LU-2220N-7, connect an air device to thepresser lifting cylinder and actuate the solenoid valve[No. 8] manually. In the state that the air cylinder is pro-truded, install the window plate on the sewing machine.The presser lifting cylinder comes in the two types.o LU-2220N-7 Part No. PA400200300

o LU-2210N/W-7o LU-2260N/W-7 Part No. PA400200200o LU-2212N-7

0– 0.3


+1.0–0.8

– 74 –

1) Releasing Torque Adjustment

2) How to reset the Safety Mechanism

(15) Safety Mechanism

Torque = P (N) x L (m)

L

P

A

Standard Adjustment

Standard specification of the releasing torque = 11.76 to 14.7N•m

(120 to 150kgf•cm)

– 75 –

1) Releasing Torque AdjustmentChange the pressure of the safety clutch (if the safety clutch is hard tobe released or it is released too easily) following the procedure de-scribed below.1. Remove the timing belt from the lower sprocket .2. When the adjusting screw is fastened, the pressure of the safety

clutch will be increased. When the adjusting screw is loosened, thepressure of the safety clutch is decreased.

3. Fix the lower sprocket and turn the safety clutch bushing untilthe safety clutch pawl comes off the groove on the safety clutchbushing . A torque developed at the time when the safety clutchpawl comes off the groove is taken as the releasing torque.

4. Adjust the standard releasing torque to 13.23 ± 1.47N•m (135±15kgf•cm).

5. After adjustment, put the timing belt on the lower sprocket.(Refer to [5.-(3) How to replace the Timing Belt] for how to put thetiming belt on the lower sprocket).

2) How to reset the Safety MechanismIf an excessive load is applied to the hook driving shaft, the safety clutchwill be released. In this case, the hook will not rotate even if the hand-wheel were turned.1. Reset the safety mechanism with the machine head tilted.2. Insert the screwdriver (medium) supplied with the machine into

the hole A in the safety clutch bushing .3. Hold the screwdriver (medium) supplied with the machine by hand

to prevent the safety clutch bushing from turning, and rotate thehand-wheel in the reverse direction.

4. When the safety clutch clicks, the safety clutch pawl fits in thegroove on the safety clutch bushing . This completes the resettingprocedure of the safety clutch.


o If the releasing torque is set to anexcessively high value:• The hook, hook driving shaft

gear or related components willbreak.

o If the releasing torque is set to anexcessively low value:• The safety clutch will be re-

leased too easily. His will impairsmooth operation of the sewingmachine.

– 76 –

Z

(16) Lubricating Unit

LU-2210N/W-7, LU-2212N-7, LU-2220N-7

LU-2260N/W-7

Z

To supply oil tothe face platecomponents

Oil wick

Return oil wick

As viewed from side Z

5 to 7mm

Standard Adjustment

1) Oil Distribution Diagram2) Supplying and Replacing Oil

– 77 –

1) Oil Distribution DiagramThe oil distribution diagram is shown on the left.

2) Supplying and Replacing Oil

Take care of the following points when supplying or replacing oil.(1) Check whether or not the oil level reaches the specified level on the oil level gauge .

Supply oil to the tank until the [H] line on the oil level check window is reached. Perform the warming-upoperation of the machine until oil flow from the hook driving shaft saddle is confirmed. Then, stop themachine. At that time, the oil surface in the tank should reach a level within the range of [H] and [L] tosatisfy the specified level of oil. If the oil surface fails to reach the specified level, supply oil from the oil port

.(Caution) Be sure to close the oil port cap .(2) Inspect the oil sight window to make sure that oil is supplied to the hook (Oil spouts from the oil reservoir

and flows toward the hook driving shaft saddle).(Oil should always accumulate by the depth of approximately 1 mm of the bottom of the oil sight window.This is the proper amount of oil to spout from the oil reservoir).

(3) Observe the oil flow in the urethane tube from the lower section of the bed to check whether or not oil isfed to the hook driving shaft saddle and then circulated.

(4) Carefully observe the filter to check whether or not oil changes in color, due to oxidation and deterioration.If oil changed in color obviously, replace the deteriorated oil with new oil without delay. To change oil,loosen the drain cock (hexagon head bolt) located under the bed tank and expel the deteriorated oilfrom the drain outlet. Remove the top cover of the bed, clean inside the bed with cleansing oil and dry itwith an air-blow. At this time, take care not to allow any foreign material, including a screw, to enter the bedtank. After the bed tank is drained and cleaned, securely fasten the drain cock . (As reference, replaceit every 500 hours of operation of the sewing machine).When replacing the oil, also replace the filter with a new one. (Refer to next page for how to replace it).

(Caution) When replacing oil, also replace the packing (Part No. RO068190100) for the drain cock and the packing (Part No. 10701209) for the bed top cover with new ones.Be sure not to use any oil other than JUKI New Defrix Oil No. 1.

Line H

Line L

– 78 –

3) Filter Replacement Procedure

4) Adjusting the amount of oil in the hook and cleaning the hook filter

25mm

A pieceof paper

Requirement:Operate the sewing ma-chine for 5 seconds at thespeed of 3,500 rpm.

Set screws

Set screws

O-ring

Standard Adjustment

– 79 –

3) Filter Replacement ProcedureRemove the magnet and filter element in the filter and washthem once a month after the first operation of the machine.

4) Adjusting the amount of oil in the hook and cleaning the hook filterOil amount in the hook(1) Oil splashes from the race surface as illustrated in the sketch.(2) When the oil adjusting screw is fastened (turn the screw clock-

wise), the oil amount in the hook is decreased.(3) When the oil adjusting screw is loosened (turn the screw coun-

terclockwise), the oil amount in the hook is increased.(Caution) The adjusting screw can be turned by a quarter revo-

lution, within which the amount of oil in the hook canbe adjusted from the minimum to the maximum value.If the adjusting screw is excessively turned, the rub-ber ball placed inside the tapped hole will be crushedand the amount of oil in the hook will no longer be ad-justed. So take the greatest care.

How to clean the Filter in the HookIf the filter is clogged, the machine cannot be oiled. So it is neces-sary to clean the filter periodically. Clean the filter following the proce-dure described below.(1) Remove the hook from the main unit of the sewing machine. Loosen

the oil amount adjusting screw and take out the rubber ball placed inside the tapped hole.

(2) Blow air to the tapped hole of the oil amount adjusting screw .


o If the filter element is cloggedwith dust or the like, a return oilflow may fail. In this case, oil mayoverflow the top of the hook drivingshaft saddle, resulting in oilleakage.

o If the oil amount in the hook is in-sufficient, the hook may generateheat. As a result, the hook will soonwear out, so causing seizure.

o If the oil amount in the hook is ex-cessive, the thread or material maybe stained with oil. Also, the oilconsumption will be larger.

– 80 –

(17) Aperture Plate Removal Procedure (for LU-2212N-7)

Standard Adjustment

1) Removal Procedure of Aperture Plate2) Attachment Procedure of Aperture Plate3) Adjustment of 2P Cylinder Connecting Link

Notch

Center of Fulcrum ShaftA

B

– 81 –

1) Removal Procedure of Aperture Plate1. Remove the conversion link hinge screw .2. Loosen the set screw (four locations) on the conversion link base

and remove the conversion link base .3. Loosen the 2P cylinder set screw and remove the 2P cylinder .4. Loosen the cylinder connecting bar hinge screw nut of the re-

verse feed cylinder and remove the cylinder connecting bar hingescrew .

5. Loosen the set screw (three locations) of the cylinder set plateand remove the cylinder set plate .

6. Remove the aperture plate set screw (four locations) and removethe aperture plate .

2) Attachment Procedure of Aperture Plate1. Attach the aperture plate with the aperture plate set screw

(four locations).2. Attach the cylinder set plate temporarily with the cylinder set plate

set screw (three locations).3. Attach the cylinder connecting bar hinge screw of the reverse

feed cylinder and fasten the cylinder connecting bar hinge screwnut .

4. Adjust the cylinder set plate and attach it so that it is parallel withthe head of the machine (in the direction of arm shaft), and that thecylinder connecting bar is parallel with the shaft center of the re-verse feed cylinder . Then fasten the cylinder set plate set screw

.5. Attach the 2P cylinder temporarily with the 2P cylinder set screw

.6. Adjust the conversion link base and attach it so that the 2P cylin-

der connecting link is parallel with the shaft center of the 2P cylin-der . Then, fasten the conversion link base set screw and fas-ten the 2P cylinder set screw .

7. Fasten the conversion link hinge screw .

3) Adjustment of 2P Cylinder Connecting Link1. Connect air hoses to all the air cylinder couplings.2. Arrange the air route.3. Loosen the eccentric pin set screw (two locations).4. Align the notch of the eccentric pin in the direction of the fulcrum

shaft of the conversion link .5. Turn the eccentric pin in the direction A or B and move the 2P

cylinder connecting link to the right and left by hand. Then stop itwhen backlash is felt and fasten the eccentric pin set screw .


6’ Confirm that the feed regulatorlink projects from the centerof the long hole section of theaperture plate . If the projec-tion point is deviated from thecenter, adjust the 2P cylinder position to the right or left andadjust the conversion link base

again.

1’ Connect the air hoses so thatthe seal No. of the air hose iscorresponding to the couplingNo.

5’ Direction A: Backlash increasedDirection B: Backlash de-creased* Adjust it so that backlash is

minimized.

– 82 –

(18) Aperture Plate Removal Procedure (for LU-2220N-7)

Standard Adjustment

1) Removal Procedure of Aperture Plate2) Attachment Procedure of Aperture Plate3) Adjustment of 2P Cylinder Connecting Link

Notch

Center of Fulcrum ShaftA

B

– 83 –


1) Removal Procedure of Aperture Plate1. Remove the conversion link hinge screw .2. Loosen the set screw (four locations) on the conversion link base

and remove the conversion link base .3. Loosen the 2P cylinder set screw (four locations) and remove the

2P cylinder .4. Loosen the cylinder connecting bar hinge screw nut of the re-

verse feed cylinder and remove the cylinder connecting bar hingescrew .

5. Loosen the reverse cylinder setscrews (four locations) and takeout the reverse cylinder .

6. Loosen the set screw (three locations) of the cylinder set plateand remove the cylinder set plate .

7. Remove the aperture plate set screw (four locations) and removethe aperture plate .

2) Attachment Procedure of Aperture Plate1. Mount the aperture plate by means of the window plate setscrews

(four locations).2. Temporarily fasten the cylinder mounting plate by means of the

cylinder mounting plate setscrews (three locations).3. Mount the reverse cylinder on the cylinder mounting plate by

means of the reverse cylinder setscrews (four locations).4. Mount the cylinder connecting lever hinge screw of the reverse

cylinder and tighten the cylinder connecting lever hinge screw nut.

5. Adjust the cylinder mounting plate so that it is horizontal to themachine head (in the direction of the main shaft) and the cylinderconnecting lever is in parallel to the shaft core of the reversecylinder . In this state, tighten the cylinder mounting plate setscrews

.6. Temporarily fasten the 2P cylinder by means of the 2P cylinder

setscrews (four locations).7. Adjust the conversion link base so that the 2P cylinder connecting

link is in parallel to the shaft core of the 2P cylinder . In thisstate, tighten the conversion link base setscrews (four locations).

8. Tighten the 2P cylinder setscrews (four locations).9. Install the conversion link hinge screw .

3) Adjustment of 2P Cylinder Connecting Link1. Connect air hoses to all the air cylinder couplings.2. Arrange the air route.3. Loosen the eccentric pin set screw (two locations).4. Align the notch of the eccentric pin in the direction of the fulcrum

shaft of the conversion link .5. Turn the eccentric pin in the direction A or B and move the 2P

cylinder connecting link to the right and left by hand. Then stop itwhen backlash is felt and fasten the eccentric pin set screw .

6’ Confirm that the feed regulatorlink projects from the centerof the long hole section of theaperture plate . If the projec-tion point is deviated from thecenter, adjust the 2P cylinder position to the right or left andadjust the conversion link base

again.

1’ Connect the air hoses so thatthe seal No. of the air hose iscorresponding to the couplingNo.

5’ Direction A: Backlash increasedDirection B: Backlash de-creased* Adjust it so that backlash is

minimized.

– 84 –

• Set the 2P stitch dial to “6” on the scale.

(1) Operation Switches

4. Various Switches

(2) Knee Switch

B

A

• Pressing the knee switch changes thestitch length from “9” to “6”.

Standard Adjustment

(LU-2210N/W-7, LU-2260N/W-7)

(LU-2212N-7)

• Needle thread clamp switch(LU-2220N-7)

Example

• Set the stitch dial to “9” on the scale.

• Pressing the switch returns the stitchlength of “6” to “9”.

OFF ONON OFF

(LU-2220N-7)

– 85 –

(1) Operation Switches1) One-touch type reverse feed switch

In the sewing machine operation, reverse feed stitching is performedduring the pressing of this switch. When the switch is released, nor-mal feed stitching is returned.

2) Altemating vertical movement amount change-over switch for the amount of alternating vertical movement of the walking footand the presser footPressing this switch raises the alternating vertical movement of thewalking foot and the presser foot to the maximum value (The lampembedded in the button is turned on). (For the LU-2220N-7, the up-per LED of the switch is lit in the state of switch ON.)Use it on the material overlapped section where the feed of the ma-terial is hard.

3) Automatic Reverse Feed Stitching Cancellation/Extra Switch • When this switch is pressed while the automatic reverse feed stitch-

ing has been set then the automatic reverse feed stitching is notperformed (only once immediately after this switch is pressed).

• When this switch is pressed while the automatic reverse feed stitch-ing has not been set then the automatic reverse stitching is per-formed (only once immediately after this switch is pressed).

4) Needle Lifting Switch Pressing this switch moves the needle position from the lower stopposition to reverse feed stitching position. (The hand-wheel pointer

shows the graduation [B] on the hand-wheel).

5) 2P Switch (For the LU-2212N-7, LU-2220N-7)Pressing this switch changes the stitch length to the one specified onthe scale of the 2P stitch dial. (The lamp embedded in the button isturned on). (For the LU-2220N-7, the upper LED of the switch is litin the state of switch ON.)

(Caution) The value specified on the scale of the 2P stitch dialshould be smaller than that in the stitch dial.

6) Needle thread clamp device switch (LU-2220N-7)In the state of switch ON, the needle thread clamp device functionsto perform needle thread clamp device at the beginning of sewing. Inthe state of switch OFF, the needle thread clamp device does notfunction.This function is related to the motor setting conditions. For moredetails, please refer to the [Instruction Manual for Models of HeavyMaterials (Complementary) SC-510] included in accessories.

(2) Knee Switch1) Pressing this knee switch brings the alternating vertical move-

ment of the walking foot and the presser foot to the maximum value.(The same result, of pressing the converting switch for theamount of alternating vertical movement of the walking foot and thepresser foot on the machine head, will be secured).

2) Also, using the function setting in the sewing machine controller, itcan be used as the presser lifting switch. (In this case, it does notfunction as the converting switch for the amount of alternating verti-cal movement of the walking foot and the presser foot).


– 86 –

5. Part Replacement(1) How to replace the Needle Clamp (LU-2260N/W-7)

A

Hole for presser adjusting dial

Hole for pulling outthe needle bar

Tapped hole for thread take-up lever cover set screw

(As viewed from side A)

Cross Section of Connecting Portion

Assembling and Disassembling Procedure

– 87 –

1. Remove the presser adjusting dial and the thread take-up levercover .

2. Loosen the clamping screw of the needle clamp (assembly) through the hole for pulling out the needle bar with the hexagon wrenchsupplied with the machine and remove the needle clamp (assembly)

.3. Insert the rotation stopper pin in the needle clamp (assembly)

so that it is placed in the groove of the needle bar , and fastenthe set screw .

4. Attach the presser adjusting dial and the thread take-up levercover . (Set the pressure to the standard adjustment value whenthe presser adjusting dial is installed. Refer to [5-(2) Replacementof the Presser Adjusting Spring].

(Caution) The maximum sewing speed varies in accordance withthe needle gauge. Set the speed to the proper one.

Assembling and Disassembling Procedure Results of Improper Adjustment

– 88 –

(2) Replacement of the Presser Adjusting Spring

o For LU-2210N/W-7, LU-2212N-7 and LU-2220N-7, ø1.8is the standard. Other are optional.

o For LU-2260N/W-7, ø2.0 is the standard. Others are op-tional.

Model Name Presser Adjusting Spring Pressure L (mm)

(Diameter) N (kgf)

LU-2210N/W-7

LU-2212N-7 88.2 (9) 82.5±0.5

LU-2220N-7

LU-2260N/W-7 98 (10) 82.5±0.5

Pressure of the Presser Adjusting Spring

10717007

(ø2.0)

Presser adjusting spring Diameter

10718302 ø1.4

10715902 ø1.8

10717007 ø2.0

Presser adjustingspring shaft

Pipe

Presser adjusting springreceiver (lower)

L


Presser Adjusting spring (assembly)

10715902

(ø1.8)

– 89 –

1. Remove the presser adjusting dial , and lower the presser foot .2. Remove the presser adjusting spring (assembly) .3. Remove the spring pin (upper) and the snap ring (E-ring) . Then,

remove the presser adjusting spring receiver (upper) .4. Replace the presser adjusting spring with that for 2-needle (ø2).5. Set the presser adjusting spring receiver (upper) , snap ring (E-

ring) and spring pin (upper) . (Presser adjusting spring (assem-bly) ).

6. Attach the presser adjusting spring (assembly) . At that time, se-curely place the spring pin (upper) into the groove of the presseradjusting spring receiver and the spring pin (lower) into thegroove of the presser bar guide arm .

7. Attach the presser adjusting dial and set the pressure to the stan-dard pressure value. o For LU-2210N/W-7, LU-2212N-

7 and LU-2220N-7, ø1.8 is thestandard. (Others are optional).

o For LU-2260N/W-7, ø2.0 is thestandard. (Others are optional).

Presser Adjusting Spring(assembly)

10718351 ø1.4

40064240 ø1.8

10717056 ø2.0


o When the presser adjusting spring is replaced, the above steps 3

to 5 are not required if it isreplaced as an assembly . Thepart No of the assembly is asfollows:

Diameter

– 90 –

(3) How to replace the Timing Belt

C

A

B

D


– 91 –

1. Remove the timing belt from the lower sprocket .2. Remove the hand-wheel.3. Remove the aperture plate.4. Remove the set screw of the reverse feed cylinder installation

base and lower the installation base in the direction of arrowA until the arm hole in the arm can be observed. (Except for LU-2212N-7 and LU-2220N-7)

5. Insert the hexagon wrench (3 mm) through the arm hole andloosen the set screw of the main shaft bearing bush.

6. Loosen the sprocket set screw .7. Fit the top end of the screwdriver in notches and on the arm

and draw out the main shaft bearing bush (assembly).8. Shift the sprocket in the direction of arrow C as illustrated in the

figure and shift the timing belt in the direction of arrow B.9. Push the timing belt out from the hole in the machine arm and

draw it in the direction of arrow D to detach it from the main shaft.

10. Remove the feed adjusting tension spring from the feed adjust-ing eccentric pin.


3’ Refer to [3-(17) and (18)Aper tu re P la te Remova lProcedure (for LU-2212N-7andLU-2220N-7)] for how to removethe aperture plate for LU-2212N-7.

– 92 –


(For LU-2212N-7 and LU-2220N-7)

1mm A clearance of 1 mm should be provided between thespring rack hook and the end face of the feed adjust-ing arm .

(For LU-2212N-7 and LU-2220N-7)

– 93 –

11. Loosen the clamping screws and of the feed adjusting arm and the feed adjusting pin support arm (For LU-2212N-7 andLU-2220N-7).

12. Loosen the clamping screw of the thrust collar .13. Loosen the clamping screw of the reverse feed connecting arm

.14. Set the stitch dial to the maximum value on the scale. Then,

remove the face aperture plate on the front face of the sewing ma-chine.

15. Loosen the clamping screw (two locations) of the feed adjusting

pin . (For LU-2212N-7 and LU-2220N-7)16. Remove the tension spring of the reverse feed lever . Draw out

the reverse feed lever shaft to a position where the timing beltcan be removed. Then, remove the spring rack hook , the feedadjusting tension spring , the feed adjusting arm and the feedadjusting pin support arm (For LU-2212N-7 and LU-2220N-7).

17. Replace the timing belt with a new one and put it on the uppersprocket.

18. Insert the reverse feed lever shaft inside the periphery of thetiming belt. Attach the feed adjusting pin support arm (For LU-2212N-7 and LU-2220N-7), spring rack hook and feed adjustingarm onto the reverse feed lever shaft .

19. Insert the reverse feed lever shaft in the shaft hole in the ma-chine arm. Fasten the set screw of the thrust collar .

20. Fasten the set screw of the feed adjusting pin . At that time,fasten the screw so that the pin roller is in a position where itrotates smoothly. (For LU-2212N-7 and LU-2220N-7)

21. Fasten the set screw of the feed adjusting arm . At that time,fluctuate the feed adjusting arm to the right and left until the feedadjusting arm is placed almost at the center of the play, thenfasten the clamping screw.

(Caution) Fasten the clamping screw with a tightening torque of3.92 to 4.9 N•m (40 to 50 kgf•cm).

22. Fasten the clamping screw of the feed adjusting pin support arm (For LU-2212N-7 and LU-2220N-7).

23. Put the feed adjusting tension spring onto the spring rack hook and the feed adjusting eccentric pin.

24. Fasten the clamping screw of the reverse feed connecting arm and attach the face aperture plate on the front face of the sewing

machine.25. Attach the tension spring of the reverse feed lever in place.


11’ Insert the screwdriver from theaperture plate side.

12’ Insert the screwdriver from theaperture plate side and from theunder surface of the bed.

14’ For LU-2212N-7 and LU-2220N-7:

• Set the stitch dial to the maximumvalue on the scale. After that, re-move the 2P stitch dial . Loosenthe set screw of the apertureplate on the front face of the sew-ing machine and remove the faceaperture plate B on the frontface of the machine.

19’ Fasten the set screw of thethrust collar while eliminatinga thrust play at the reverse feedlever shaft .

21’ If the feed adjusting arm isnot correctly positioned, the feedconnecting rod may fail to oper-ate normally, the feed adjustingarm may interfere with the in-ner wall of the arm, and the feedadjusting arm may be pushedagainst the side face of the feedcrank stud. In this case, the re-verse feed lever may not belifted/lowered smoothly.

23’ Set the stitch dial to the maxi-mum value on the scale. Adjustso that a clearance of 0.5 to 1.5mm is provided between the re-verse feed lever and the stop-per when the reverse feed lever

is slightly pushed down, andthen fasten the clamping screw

.(Refer to [3.-(8) Position of theReverse Feed Connecting Arm]for further details.

24’ For LU-2212N-7 and LU-2220N-7:

• Fasten the clamping screw ofthe reverse feed connecting arm

and attach the face apertureplate B on the front face of themachine. After that, attach the 2Pstitch dial .

– 94 –

When the timing belt is put on the lower sprocket , take care to set the correct timing betweenthe needle and the hook.After the timing belt has been properly set on the machine, check the [Timing between the needleand the hook], [Feed rock timing], [Feed driving timing] and [Height of the feed dog].


– 95 –

26. Hang the timing belt on the upper and lower sprockets . Atthat time, do not change the needle-to-hook timing while the timingbelt is being hung.

27. Check the timing between the needle and the hook.28. Check the feed rock timing.29. Check the feed driving timing.30. Check the height of the feed dog.31. Fasten the clamping screw while pressing the hand-wheel against

the main shaft bearing.


27’ Refer to [3-(4)-3) Timingbetween the Needle and theHook].

28’ Refer to [3-(6)-1) Feed RockTiming].

29’ Refer to [3-(6)-2) Feed DrivingTiming].

30’ Refer to [3-(6)-4) Height of theFeed Dog].

– 96 –

(4) How to change from 1-needle to 2-needle specifications (LU-2210N-7 →→→→→ LU-2260N-7)

Hook shaft saddle (left) set

Filter(For lubrication)

Face aperture plate


– 97 –

1. Remove the sliding plate (right) and (left) and the needle. Then, tilt the machine head.2. Loosen the clamping screw of the hook driving shaft set collar.3. Loosen the set screws (2 pcs.) of the hook driving shaft coupling (left) and pull out the hook driving shaft B.4. Remove the throat plate, feed dog, presser foot (assembly) and walking foot (assembly).5. Fix temporarily the hook shaft saddle (left) on the bed. To attach the hook shaft saddle (left) , screws

(2 pcs.) and washers (2 pcs.) are necessary, but an eccentric pin is not necessary.6. Loosen the set screws (2 pcs.) to the extent that the hook shaft saddle (right) moves to the right and left.7. Attach both the feed dog and the throat plate for 2-needle.8. Remove the face plate, presser adjusting screw and thread take-up lever cover, and loosen the clamping

screw of the needle bar connecting stud to pull out the needle bar.9. Temporarily attach the needle bar for 2-needle.10. Attach the needle clamp (assembly).11. Attach the hook driving shaft coupling (left) through the hook driving shaft C .12. Attach the needle and adjust the [Height of the needle bar], [Clearance between the needle and the blade

point of hook], [Timing between the needle and the hook], and [Clearance between the throat plate and theinner hook stopper]. The adjustment for the left and right needles is the same.

13. Remove the return oil pipe A (for 1-needle) . Then connect the lubricating pipe C (for 2-needle) fromthe pipe joint on the upper side of the hook shaft saddle (right) to the pipe joint on the lower side of thehook shaft saddle (left) . Then, connect the return oil pipe A (for 2-needle) from the pipe joint on thelower side of the hook shaft saddle (left) to the filter (for return oil) . Attach the cable band to therespective pipe joints to fix the pipes.

14. Attach the lead for the right and left thread trimmer solenoids. At that time, be sure to insert two solenoidleads in one hole of the terminal base .

15. Adjust the right and left of the [Thread trimmer] and [Opener].16. Replace the presser adjusting spring with a new one for 2-needle.17. Loosen the thread tension (assembly) set screws (2 pcs.) and replace the thread tension controller

(assembly) with a new one for 2-needle.18. Set the stitch dial to [0] on the scale. In this state, loosen the stitch dial set screw and replace the

stitch dial with a stitch dial for 2-needle. At that time, make sure that the stitch dial pin and the spring are placed in position.

19. Remove the thread guide B in the arm and attach the felt thread guide and felt . At that time, the setscrew of the thread guide should be replaced as well.

20. Attach the face plate, presser adjusting screw, thread take-up lever cover and slide plates (left) and (right).(Caution) Refer to the List of the Parts to be changed (next page)


– 98 –

No. Part No. Description Q’ty Details of set Remarks

1 10771772 Unit for mode change 1

2 10771764 Hook shaft base (left) set 1

3 10771756 Hook shaft base (left) (assembly) (1)

4 10726552 Counter knife base (assembly) (1)

5 SM6052502TP Counter knife base (assembly) set screw (2)

6 WP0520656SA Counter knife base (assembly) set screw washer (2)

7 10726800 Moving knife shaft (1)

8 10726305 Moving knife (1)

9 SM6030802TP Moving knife set screw (2)

10 WP0320501SC Moving knife set screw washer (2)

11 B2311019000 Moving knife shaft spring (1)

12 10772804 Thread trimmer solenoid (1)

13 10772200 Thread trimmer solenoid mounting plate (left) (1)

14 SM6040602TP Thread trimmer solenoid set screw (2)

15 SM6040602TP Thread trimmer solenoid mounting plate set screw (2)

16 10772101 Thread trimmer solenoid arm (left) (1)

17 SM8050602TP Thread trimmer solenoid arm (left) set screw (2)

18 10771806 Moving knife driving arm C (1)

19 10772507 Moving knife driving arm E (1)

20 10771905 Moving knife driving link (A) (1)

21 10772002 Moving knife driving link (B) (1)

22 SM6041202TP Moving knife driving arm C clamping screw (1)

23 SD0500301SP Moving knife driving link (A) hinge screw (2)

24 SD0500301SP Moving knife driving link (B) hinge screw (2)

25 CS0790731SH Moving knife shaft thrust plate (1)

26 SS8110422TP Moving knife shaft thrust plate set screw (2)

27 10728160 Moving knife driving arm A joint (1)

28 10727709 Thread trimmer cam (1)

29 SM6041202TP Thread trimmer cam set screw (3)

30 10722551 Hook (assembly) (1)

31 10724607 Hook driving shaft set collar (1)

32 SM6051402TP Hook driving shaft set collar set screw (1)

33 SM6062002TP Hook shaft base set screw 2

34 WP0641601SD Hook shaft base set screw washer 2

35 10772705 Hook driving shaft C 1

36 10773364 Thread tension (assembly) 1

37 22603609 Felt thread guide 1

38 22603708 Felt 1

39 SS2090710SP Felt thread guide set screw 1

40 10771459 Stitch dial (assembly) 1

41 10717007 Presser adjusting spring 1

42 10771103 Needle bar 1

43 SM6030502TP Needle clamp screw 1

44 BT0600402EA Hook shaft base oil pipe C 0.18m

45 BT0500300EO Hook shaft base return oil pipe A 0.26m

46 EA9500B0100 Cable clip 3

47 10777407 Hexagon wrench 2.5 mm 1

● List of the Parts to be changedWhen the mode is changed from 1-needle to 2-needle, perform the changing work according to the unit as thepart No. of the unit for mode change have been set.

List of Unit for mode change

– 99 –

6. Bed Height AdjustmentStandard Adjustment

When the sewing machine head is installed on thesewing machine table in the standard state, thetop surface of the sewing machine bed is 2 mmhigher than the top surface of the table as illus-trated in the figure on the left.

If the sewing machine is to be used with the bed lowered as shown by the arrow,remove the rubber spacers (2 pcs.) , rubber cushions (4 pcs.) shown with obliquelines and attach the hinge seat and the machine head support rubber pieces inplace.

2mm

No. Part Name Part No.

Rubber spacer 10742005

Rubber cushion 10740900

When driving Nail A, the nail should be driven slantwise so that the side surface of the accessory case cannotbe penetrated.

Top surface of the table

Nail Nail Nail

Accessory caseAccessory case

A

A

– 100 –

B

C

N

D

G

K

L

J

H

E

A

IHook shaft saddle

Connecting link A

Alternating vertical movementconverter shaft

Reverse feedlever shaft

Knee lifter shaft

Feed rock shaft

Feed adjusting connecting rod

Feed driving shaft

F

7. Parts to be carefully tightenedThe following parts will break if they are excessively tightened. So, fasten the screws carefully in the respectiveparts.

Part No. Part Name Part No. Part Name

A 10718104 Feed rock shaft clank H 10727808 Moving knife driving arm B

B 10729705 Presser lifter arm I 10728103 Moving knife driving arm A

C 10721207 Reverse feed connecting arm J 10713907 Top feed arm

D 10720506 Feed adjusting arm K 10718104 Feed driving shaft crank

E 10720308 Feed adjusting converting arm L 10718609 Feed driving arm

F 10735900 Cylinder arm for the alternating vertical M 10771806 Moving knife driving arm Cmovement of the walking foot and pre-sser foot

G 10715209 Adjusting arm for the alternating N 40025558 Stitch dial pin support armvertical movement of the walking (For LU-2212N-7, LU-2220N-7)foot and presser foot

M

I

– 101 –

No. Description Part No. LOCK-TITE type No.1 Moving knife driving link hinge screw SD0500481TP LOCK-TITE #6382 Cam roller shaft hinge screw SD0500721SP LOCK-TITE #6383 Feed adjusting base set screw SS7110710SP LOCK-TITE #6384 Safety mechanism spring hinge screw and SD0640322TP LOCK-TITE #242

safety mechanism claw hinge screw5 Engaging section of the feed adjusting arm and 10720506, 10721504 LOCK-TITE #638

stitch dial pin6 Stitch dial pin set screw SS7110810SP LOCK-TITE #6387 Feed connecting link B support pin screw SM8050602TP LOCK-TITE #2428 Top feed connecting converting unit support SM8050602TP LOCK-TITE #242

pin set screw9 Top feed converting unit shaft set screw SM8050602TP LOCK-TITE #242

10 Reverse feed connecting arm hinge screw SD0800352SP LOCK-TITE #63811 Hook driving shaft bearing holder set screw SS8080610SP LOCK-TITE #24212 Thread take-up crank pin 10524106 LOCK-TITE #63813 Amount of alternating vertical movement of the walking 10715209, 10715308 LOCK-TITE #638

foot and presser foot adjusting arm and converting unit arm pin14 Variable speed resistor link hinge screw SD0550212TP LOCK-TITE #63815 Top cover and dial bush of alternating vertical 10742609, 10715100 LOCK-TITE #638

movement of the walking foot and presser foot16 Needle bar frame and needle bar fame driving shaft 10708402, 10708709 LOCK-TITE #63817 Needle bar frame and roller guide base screw 10708469, SM6041012TP LOCK-TITE #63818 Feed adjusting arm and feed adjusting connecting rod pin 10720506, 10725307 LOCK-TITE #63819 Tension release presser pin and tension release push screw 10702702, 10702801 LOCK-TITE #24220 Presser lifter arm and converter arm pin 10729705, 10715308 LOCK-TITE #63821 Tension release arm and tension release arm pin 10729903, 10730000 LOCK-TITE #63822 Alternating vertical movement stopper plate 10714400, B3416552000 LOCK-TITE #638

and stopper plate hinge screw23 Alternating vertical movement shaft spring 10714905, 11007101 LOCK-TITE #638

suspension bracket and spring hinge screw24 Side pate on the front face and side plate positioning pin 10737005, 10704302 LOCK-TITE #63825 Cylinder connecting screw and cylinder 10737013, SD0720331SP LOCK-TITE #638

connecting screw hinge screw26 Hook shaft saddle lower plate and opener shaft oil seal 10724300, 10726107 LOCK-TITE #63827 Hook driving shaft and hook driving shaft gear screw 10722304, SS2090710TP LOCK-TITE #63828 Moving knife driving link A hinge screw and SD0500301SP LOCK-TITE #638

moving knife driving link B hinge screw29 Opener arm shaft B 10770501 LOCK-TITE #24230 Face aperture plate B and face aperture place 40027141, 10704302 LOCK-TITE #638

pilot pin31 Engaging section of feed adjusting bracket 10720506, 40025557 LOCK-TITE #638

and feed adjusting pin (A)32 Feed adjusting pin (A) set screw SS7110810SP LOCK-TITE #63833 Feed adjusting base A set screw SS7110710SP LOCK-TITE #63834 Feed adjusting base B set screw SS7110710SP LOCK-TITE #63835 2P cylinder connecting screw and cylinder 10737013, SD0720331SP LOCK-TITE #24336 Moving knife shaft setscrew SM8040412TP LOCK-TITE #63837 Moving knife return pin 40058148 LOCK-TITE #63838 Cam roller shaft setscrew SM8040412TP LOCK-TITE #63839 Counter knife base stopper screw SM9040603SP LOCK-TITE #63840 Counter knife driving arm hinge screw SD0800426TP LOCK-TITE #24341 Thread presser (Needle thread clamp device) 40058067 LOCK-TITE #638

8. Parts to be fixed with LOCK-TITE PaintThe following parts are fixed with “LOCK-TITE” paint. When these parts are disassembled, remove residual paintthoroughly using pint thinner and assemble them applying “LOCK-TITE” after removing any moisture from the surface.If the screw which has been fixed with “LOCK-TITE” paint, is too hard to loosen, it is advisable to warm it up using atorch lamp. This will make the screw easily come off.

* : Are applicable only to the LU-2212N-7 and LU-2220N-7.** : Only for the LU-2220N-7

*

*

* * * ** ** ** ** ** ** *

– 102 –

No. Part No. Part Name Specifications Instruction in attachment

MC321001400 Needle 134 x 35R (Standard: Nm 140) 2210N-7/2212N-7/2210W-7/2220N-7 Selection: • Orientation of the Needle

1 • Refer to [3.-(4)-2) Clearance between

MC321001402 Needle 134 x 35R (Standard: Nm 140) 2260N-7/2260W-7 (2-needle) the Needle and the Blade Point of

Hook] and [3.-(4)-3) Timing between

Needle and the Hook].

10756757 Hook (assembly) 2-fold hook 2210W-7/2260W-7 Selection:

2 • Refer to [3.-(4)-2) Clearance between

10761252 Hook (assembly) 2210N-7/2260N-7/2212N-7/ the Needle and the Blade Point of

2220N-7 Hook] and [3.-(4)-3) Timing between

Needle and the Hook].

10759603 Aluminum bobbin (with a knurling tool) 2210N-7/2260N-7/2212N-7/2220N-7

3 21334800 Aluminum bobbin (with a knurling tool) 2210W-7/2260W-7 Selection

40018350 Aluminum bobbin A 2210N-7/2212N-7/2220N-7

10726305 Moving knife 2210N-7/2210W-7 • Refer to [3.-(10)-3)

4 2260N-7/2260W-7

21389200 Moving knife Only 2212N-7 • Refer to [3.-(11)-3 Knife Pressure].

40058051 Moving knife Only 2220N-7 • Refer to [3.-(12) Thread trimming device]

10726404 Counter knife 2210N-7/2210W-7

5 2260N-7/2260W-7

21389309 Counter knife Only for 2212N-7 • Refer to [3.-(11)-1) Counter Knife].

40058046 Counter knife Only for 2220N-7 • Refer to [3.-(12) Thread trimming device]

10726909 Clamp spring 2210N-7/2210W-7 • Refer to [3.-(10)-2) Clamp Spring].

2260N-7/2260W-7

6

21389408 Clamp spring Only for 2212N-7

40058043 Clamp spring Only for 2220N-7 (Standard) • Refer to [3.-(12) Thread trimming device]

40064213 Clamp spring Only for 2220N-7 (For thin threads) • Refer to [3.-(12) Thread trimming device]

7 40058047 Thread guide Only for 2220N-7 (Standard) • Refer to [3.-(12) Thread trimming device]

8 10727303 Filter Common type • Refer to [3.-(16) Lubricating Unit].

9. Maintenance Parts List

Basic Maintenance Parts

Maintenance Parts to be rarely replaced

• Refer to [3.-(10)-1 Counter Knife].

No. Part No. Part Name Specifications Instruction in attachment

10702405 Thread take-up spring 2210N-7/2212N-7/2210W-7/2220N-7

B3128526000 Thread take-up spring 2260N-7/2260W-7/2220N-7

2 40033293 Opener Common type • Refer to [3.-(13) Opener].

10706703 Timing belt Common type • Refer to [5.-(3) How to replace the

Timing Belt].

B3212210000 Bobbin winder friction wheel Common type • Refer to [3.-(9)-1) Bobbin Winder

Friction Wheel Adjustment].

10744308 Stitch dial Common type • Refer to [3.-(7)-1) Zeroing of the Feed

5 Adjusting Mechanism].

40027231 Stitch dial (A) assembly 2212N-7/2220N-7 • Refer to [3.-(7)-3) 2P Adjustment].

1

3

4

• Refer to [3.-(11)-1) Counter Knife

and Clamp Spring Positions].

– 103 –

10. Mechanism Adjusting Procedure Chart at a Glance

When adjusting the items 1) through 8), also adjust the related components according to the arrows.

1) [3.-(4)-2) Clearance between the Needle and the [3.-(4)-3) Timing between the Needle and the Hook]

Blade Point of Hook]

2) [3.-(5) Clearance between the Throat Plate and the [3.-(4) 2) Clearance between the Needle and the

Inner Hook Stopper] Blade Point of Hook]

[3.-(10), 3-(11) and 3.-(12) Thread Trimmer Device]

3) [3.-(6)-1) Horizontal Feed Timing] [3.-(6)-2) Vertical Feed Timing]

4) [3.-(13)-1) Timing of the Opener] [3.-(11)-7), 3.-(11)-8) and 3.-(12)-11) Thread Trimmer

Cam]

5) [3.-(11)-5) Height of the Moving Knife] [3.-(4)-2) Clearance between the Needle and the


[3.-(4)-3) Timing between the Needle and the Hook]

[3.-(10)-4) Moving Knife Driving Arms A, B and C]

[3.-(11)-7 Thread Trimmer Cam]

– 104 –

6) [5.-(3) How to replace the Timing Belt] [3.-(4)-3) Timing between the Needle and the Hook]

[3.-(6)-1) Horizontal Feed Timing]

[3.-(6)-2) Vertical Feed Timing]

[3.-(6)-4) Height of the Feed Dog]

7) [5.-(1) How to replace the Needle Clamp] [3.-(3) Needle Entry]

[3.-(4)-2) Clearance between the Needle and the



[3.-(5) Clearance between the Throat Plate and the

Inner Hook Stopper]

[3.-(2) Sewing Speed]

8) [5.-(4) How to change from 1-needle to 2-needle [3.-(3) Needle Entry]

specifications]

[3.-(4)-2) Clearance between the Needle and the



[3.-(5) Clearance between the Throat Plate and the

Inner Hook Stopper]

[3.-(10) Thread Trimmer Device]

[3.-(13) Opener]

[5.-(2) Replacement of the Presser Adjusting Spring]

[3.-(16) Lubricating Unit]

[3.-(2) Sewing Speed]

– 105 –

1. Isolated idling loop (loose 1-1) Needle thread tension is too low. Increase the needle thread tension. stitches and looped stitches) Knots of sewing threads are 1-2) Thread take-up spring tension has been 2-A) Stroke of the thread take-up spring is Increase the stroke of the thread take-up spring suddenly made on the upper improperly adjusted. too small. sufficiently. of lower side of the material as isolated idling loops 2-B) Thread take-up spring tension is insuff- Increase the tension of the spring.

iciently tensioned.

1-3) The amount of thread to be fed by Move the take-up thread guide to the right to dec-the thread take-up lever is excessive. rease the amount of thread to be fed by the ead

take-up lever.

1-4) Defective hook components 4-A) Clearance between the hook and the Re-adjust the height of the hook (Refer to [3-(5)]).inner hook stopper is too small.

4-B) Defective hook Replace the hook.

1-5) Thread path is incorrect. 5-A) Thread path is not smooth on the surface. Smoothen the thread path.

5-B) Thread path has scratches on the surface. Smoothen the thread path.

5-C) Thread is caught in some part of the thread path. Smoothen the thread path.

1-6) Defective bobbin or bobbin case 6-A) The bobbin is engaged with the inner Replace the bobbin or the inner hook.hook in a defective way. The thread iscaught in a defective engaging section.

6-B) Tension adjusting spring of the bobbin Replace the bobbin case.case is defective.

6-C) The bobbin runs idle in the bobbin case. Increase the effective amount of the idling prevention spring.

1-7) Bobbin does not wind the bobbin thread. 7-A) The bobbin winder spring pressure is Adjust the spring pressure to an adequate value.too high or too low.

1-8) Needle slot in the feed dog is too small. Use a feed dog with a larger needle slot.

1-9) Needle used is too thin for the thread used. Replace the needle or the thread.

1-10)Defective needles 10-A) Tip of the needle has burrs. Replace the needle with a new one.

10-B) Installing direction of the needle is incorrect. Re-install the needle.

Trouble Cause (1) Cause (2) Check Procedure and Corrective Measures

11. Troubles in Sewing and Corrective Measures(1) Related to Sewing

To the next page

NeedleThread

BobbinThread Isolated Idling Loop

– 106 –

1-11) Defective feed timing 11-A) Feed timing is earlier than the standard one. Re-adjust the feed timing. (Refer to [3-(6)]).

11-B)Height of the feed dog differs from the Re-adjust the height of the feed dog. (Refer to [3-standard value. (6)-4)])

1-12) Defective hook timing 12-A) Hook timing is too early. Retard the hook timing.

1-13)Defective needle entry Adjust so that the needle enters just at the centerof the needle slot in the feed dog.

1-14)Inner hook opening lever is defective. 14-A) Clearance between the hook and the Decrease the clearance.inner hook opening is too large.

1-15)Heavy threads used Replace it with the feed dog (40062827) for thick threads.

Remove the pre-tension part of the needle threadclamp device unit.

Increase the needle size number. (Replace theneedle with a thicker one.)

2. Stitch Skipping 2-1) Defective needle 1-A) Bent needle Replace the needle with a new one. Stitches are not finishing completion since sewing 1-B) The needle is installed facing in the Re-install the needle in the correct manner. threads are not made into wrong direction. stitches in part.

1-C) Tip of the needle is blunt. Replace the needle with a new one.

1-D) The needle is too thick or too thin for the Replace the needle with a new one.thread used.

2-2) Defective hook components 2-A) Blade point of the hook is blunt or worn out. Correct the blade point of the hook or replacethe hook with a new one.

2-B) Incorrect hook timing Re-adjust the hook timing.

2-C) Height of the needle bar is not correct. Re-adjust the vertical position of the needle bar inthe light of the blade point of the hook.

2-D) Clearance between the blade point of Minimize the clearance.the hook and the needle is not correct.

2-E) Effective amount of the needle guard is wrong. Adjust the effective amount of the needle guard.

2-F) Thread loops are not made with consistency. Wind the thread around the needle.

2-3) The needle thread tension is too high. Decrease the needle tension.

2-4) Sewing speed is too high. Decrease the sewing speed.


Continued from the previous page

Stitch Skipping

NeedleThread

BobbinThread

To the next page

– 107 –

2-5) Height of the needle bar is not correct. 5-A) Height of the needle bar is not adjusted Re-adjust the height of the needle bar.to the specified dimension.

2-6) Defective presser foot 6-A) The presser foot fails to rest on the throat plate. Height of the presser foot is incorrect.

2-7) Improper feed timing (bent needle). Re-adjust the feed timing.

2-8) Thread take-up spring has been improperly . 8-A) Stroke of the thread take-up spring is Decrease the tension of the spring.adjusted too high.

8-B) The thread take-up spring is too tense. Decrease the tension of the spring.

2-9) Incorrect needle entry 9-A) The needle comes in contact with the Adjust the needle entry.needle hole in the throat plate.

2-10) Improper pressure of the presser foot 10-A) Pressure of the presser foot is too low. Increase the pressure of the presser foot.

3. Needle Thread Breakage 3-1) Thread path is incorrect. 1-A) Thread path is not smooth on the surface. Smoothen the thread path. The needle thread splits finely or breaks during sewing. 1-B) Thread path has scratches on the surface. Smoothen the thread path.


3-2) Improper needle thread tension 2-A) Needle thread tension is too high or too low. Adjust the needle thread tension.

2-B) The tension controlled by the tension Adjust the tension controller No. 1 thread tensioncontroller No. 1 is too low. to prevent the thread from flapping.

3-3 Defective needle 3-A) Bent needle Replace the needle with a new one.

3-B) The needle has scratches. Replace the needle with a new one.

3-C) Tip of the needle is blunt. Replace the needle with a new one.

3-D) The needle is installed facing the wrong Re-install the needle in the correct manner.direction.

3-E) The needle is too thick or too thin for the Replace the needle with a new one.thread used.


ThreadNeedleStitch

Throat Plate

Thread Breakage


To the next page

Cloth

– 108 –

3-4) Defective hook components 4-A) Thread path of the hook has scratches. Smoothen the thread path.

4-B) Blade point of the hook is blunt or worn out. Correct the blade point of the hook or replace thehook with a new one.

4-C) Clearance between the blade point of the Widen the clearance to allow the thread to comehook and the inner hook stopper is too small. off the hook smoothly.

4-D) Hook timing is too early. Adjust the hook timing.

4-E) The inner hook opening lever provides Adjust the clearance.an excessive clearance.

4-F) The needle interferes with the blade Adjust the needle-to-hook relation.point of the hook.

3-5) Thread take-up spring has been 5-A) Stroke of the thread take-up spring is Re-adjust the stroke of the thread take-up spring.improperly adjusted too large or too small.

5-B) Tension of the thread take-up spring is Re-adjust the spring tension.too high or too low.

3-6) Sewing speed is too high. 6-A) The needle generates heat, resulting in Decrease the sewing speed.thread breakage.

Wind the thread around the needle.

3-7) The installing point of the needle is too low 7-A) Height of the needle bar is insufficient. Raise the needle bar.

7-B) Needle is not attached in the needle bar Attach the needle in the needle bar.in the correct manner.

3-8) Pressure of the presser foot is too low. 8-A) Stitches gather on the overlapped section Increase the pressure of the presser foot.of a material, resulting in thread breakage.

3-9) Incorrect needle entry 9-A) Needle interferes with the needle hole Re-adjust the needle entry point. (Refer to [3.-(3)]).edge of the throat plate.



– 109 –

4. Irregular Stitches 4-1) Defective hook components 1-A) Oil in the hook is insufficient. Adjust so that a sufficient amount of oil is supplied Knots of the needle thread and to the hook (Refer to [3.-(16)-4)]) the bobbin thread irregularly appear on the front or back of 1-B) Dust gathers on the reverse side of the Clean the inner hook. the material. inner hook

1-C) Hook timing is too early. Retard the hook timing.

1-D) Defective hook (The hook has scratches Replace the hook with a new one and/or corrector the thread path is improper, etc.) the thread path.

1-E) The inner hook opening lever provides Decrease the clearance at the inner hook openingexcessive clearance. lever.

1-F) Clearance between the throat plate and Re-adjust the height of the hook (Refer to [3.-(5)]).the inner hook stopper is too small.

4-2) Defective bobbin and/or inner hook 2-A) The bobbin is not engaged with the inner Replace the bobbin or inner hook with a new one.hook. As a result, the bobbin thread cannotbe led smoothly

2-B) Bobbin thread is not wound. As a result, Adjust the tension of the bobbin winder or thethe bobbin thread fails to be fed smoothly. position of the bobbin winder tension controller.

2-C) Bobbin runs idle in the inner hook. Increase the idling prevention spring pressure.

2-D) Defective adjusting spring tension of the Replace the inner hook with a new one.inner hook

2-E) Thread has been wound excessively on Re-wind the bobbin thread to the extent where thethe bobbin. thread wound round the bobbin does not protrude

from the periphery of the bobbin.

4-3) The needle thread tension and the bobbin Increase the thread tension.thread tension are too low.

4-4) Thread take-up spring has not been 4-A) Stroke of the thread take-up spring is too Re-adjust the stroke of the thread take-up spring.correctly adjusted. large or too low.

4-B) Tension of the thread take-up spring Re-adjust the tension of the thread take-up spring.is too high or too low.

4-5) Improper thread path 5-A) Thread path is not smooth on the surface. Smoothen the thread path.

5-B) Thread path has scratches on the surface. Smoothen the thread path.


4-6) Length of thread fed by the thread take- Move the take-up thread guide to the left andup lever is excessive or insufficient. right and adjust the length of the thread to be fed

by the thread take-up lever.

4-7) Improper feed timing Re-adjust the feed timing. (Refer to [3.-(6)]).


Stitch

Irregular stitches on theback of the material

Irregular stitcheson the front of thematerialNeedle

Thread

BobbinThread

– 110 –

5. At the beginning of sewing, the 5-1) Needle thread clamp device malfunction 1-A) Needle thread clamp switch turned OFF Make the needle thread clamp switch turned ON needle thread is protruded from (rightmost 6-gang switch). [Refer to 4. – (1).] the right side of the sewing material. (LU-2220N-7) 1-B) Improper air hose layout toward the air Check air hose connections.

cylinder of the needle thread clamp (Air hose No. 5)device

1-C) Motor setting for needle thread clamp Separate Instruction Manual for Models of Heavyprohibition Materials (Complementary)

Refer to SC-510.

5-2) Presser foot failing in rising 2-A) Improper air hose layout toward the air Check air hose connections.cylinder of the presser lifter unit. (Air hose Nos. 7 and 8)

2-B) Presser lifter unit malfunction Readjust the presser lifter.[Refer to 3. - (14) Presser Lifting Unit.]


– 111 –

1. One or two stitches skip at the 1-1) Length of thread left at the needle tip 1-A) The needle thread path is incorrect in Check the needle thread path and remove the thread start of the sewing. after thread trimming is too short. part, resulting in excessive needle thread tangled round the thread guide or correct the

tension at the time of thread trimming. position of the thread guide of the spool rest rod.

1-B) Tension of the tension disk No. 1 is too Turn the thread tension nut No. 1 counterclockwisehigh. to reduce the thread tension.

1-C) The tension disk No. 2 fails to release the Re-adjust the timing of releasing thread tension.thread sufficiently at the time of thread trimming. Also, make sure that the tension releasing solenoid

activates while the sewing machine is being energized.

1-D) Timing of thread trimming is too early. Check and adjust needle thread trimming timing accordingto [3.-(11) -7) and 8) Thread trimming cam and 3.- (12)-11)Adjustment of needle thread trimming cam timing.]

1-E) Moving knife and/or the hook has Check the hook and the moving knife for scratchesscratches. and buff them up if needed. If the knife and/or the

hook is seriously damaged, replace it with a new one.

1-F) Thread guide adjustment inadequate Adjust it referring to [3-(12)-6) Thread guide(LU-2220N-7) mounting position.]

1-2) Bobbin thread fails to be clamped. 2-A) The installing position of the clamp Adjust it referring to [3.-(10)-2) Clamp Spring] andspring is not correct. [3.-(11)-1) Counter Knife and Clamp Spring Positions].

2-B) Clamp spring pressure is too low. Adjust or replace it according to 3.-(10)-2) Clampspring, 3.-(11)-1) Clamp spring position, and 3.-(12)-12) Clamp spring mounting position.

2-C) Clamp spring has scratches or is Replace the clamp spring with a new one. damaged.

2-D) The needle thread on the material Increase the thread tension of the thread tensionside removes the bobbin thread. controller No. 1.

2-E) Thin threads (Problems of different thread The clamp spring (40064213) for thin threads shall trimming mechanisms in the LU-2220N-7) be used.

1-3) The needle, treadle and feed dog used 3-A) Needle is too thick. It is advisable to use the thinnest needle as longare not suitable, or the pressure of the as loose stitches do not occur.walking foot is too low.

3-B) The needle slot in the feed dog is too large. Replace the feed dog with one which has a smallerneedle slot.

3-C) Pressure of the presser foot is too low. Increase the pressure of the presser foot, by turningthe presser spring regulator clockwise, to the extentwhere the feed dog does not scratch the material.

3-D) Walking foot does not clamp the needle thread. Replace the walking foot with one which does nothave a slit. (Refer to [12. Replaceable Gauge Table]).


(2) Related to Thread Trimmer Device

– 112 –

2. Needle thread is likely to slip off 2-1) Needle thread slips off the needle eyelet 1-A) Length of thread trailing from the needle Refer to Cause (1)-1)-A through F and [3.-(11)-7), the needle eyelet. immediately after thread trimming. eyelet after thread trimming is too short. 8) and -(12)-11) Thread Trimmer Cam].

2-2) Needle thread slips off the needle eyelet 2-A) Length of thread trailing from the needle Refer to Cause (1)-1)-A through F and [3.-(11)-7),at the start of sewing. eyelet at the sewing start is too short. 8) and -(12)-11)Thread Trimmer Cam].

3. Thread Trimming Failure 3-1) The thread trimmer fails to cut the threads. 1-A) The moving knife blade fails to match the Check the height of the moving knife and countercounter knife blade in height and direction. knife.

1-B) The moving knife blade and counter knife Replace the moving knife and the counter knifeblade have worn out or been damaged. with new ones.

1-C) The counter knife fails to provide Re-adjust the knife pressure. (Refer to [3.-(10)-3) ,sufficient pressure. (11)-3) and -(12)-7) Knife Pressure]).

1-D) Weak thread tension Increase the tension of needle thread and bobbin thread.

1-E) Inadequate mounting position for the Make readjustments. Refer to [Needle Threadthread guide Trimming Device].

3-2) Single yarn of the thread remains 2-A) The moving knife blade and the counter Replace the moving knife and the counter knifeuntrimmed. knife blade have worn out or been damaged. with new ones.

2-B) The moving knife blade fails to match the Check the height of the moving knife and countercounter knife blade in height and direction. knife.

2-C) Timing of thread trimming is too late. Check the cam for correct timing.

2-D) The counter knife fails to provide a Re-adjust the knife pressure. (Refer to [3.-(10)-3) ,sufficient pressure. (11)-3) and -(12)-7) Knife Pressure].

3-3) The moving knife stops during thread 3-A) Thread used is too thick. Use the specified thread.trimming.

3-B) Clearance between the moving knife blade Check the lateral position of the moving knife and(outside) and the throat plate is too small. adjust it correctly.

3-C) Needle thread tension is too high. Decrease the thread tension controlled by thetension controller No. 1.

3-D) Needle thread tension is too low. Increase the thread tension controlled by thetension controller No. 1.

3-E) The bobbin thread tension is too high. Reduce the bobbin thread tension.

3-F) The pressure of the counter knife is too high. Adjust the counter knife position.

3-G) The initial position of the moving knife Check the initial position of the moving knife andis too advanced. adjust it.

3-H) The thread trimming knives are not sharp Refer to Cause 3-1) and 2) for the knife pressure enough. and thread trimmer cam.


To the next page

– 113 –

3-4) The thread trimmer fails to catch the 4-A) The last stitch at the end of sewing skips. Check the installing position of the needle and theneedle thread. hook timing, and adjust them.

4-B) Timing of the thread trimmer cam is too Check the timing of the thread trimmer cam andearly or too late. adjust it.

4-C) Top end of the moving knife has been Replace the moving knife with a new one.damaged or has scratches.

3-5) The thread trimmer rails to catch the 5-A) Stroke of the moving knife is too small. Check and adjust the initial position of the movingbobbin thread. knife.

5-B) Bobbin thread path is inappropriate. Check the bobbin thread path.(Bobbin thread slips off the bobbinthread guide of the inner hook).

5-C) The tip of the moving knife has been Replace the moving knife with a new one.damaged or has scratches.

5-D) The position of the moving knife is too Check the height of the moving knife referring tohigh or too low. [3.-(11)-5), -6) and -(12)-4) Height of the Moving Knife].

5-E) Bobbin thread tension excessive Reduce the bobbin thread tension.

3-6) The thread trimmer fails to trim the needle 6-A) The moving knife blade fails to match the Check the height of the moving knife and counter knife.thread and bobbin thread. counter knife blade in height and direction.

6-B) The moving knife blade fails to match Replace the moving knife and counter knife withthe counter knife blade in height and direction. new ones.

6-C) The counter knife fails to provide a Adjust the knife pressure. (Refer to [3.-(10)-3) andsufficient pressure. 3.-(11)-3) Knife Pressure]).

6-D) The moving knife fails to operate. Check the installing position of the moving knifedriving arm A and adjust it.

Check the operating condition of the needle threadtrimming solenoid or the needle thread trimming aircylinder.

Check the timing of the synchronizer, and adjust it.

6-E) Bobbin thread tension excessive Reduce the bobbin thread tension.



– 114 –

12. Replaceable Gauge Table(1) For LU-2210N/W-7, LU-2212N-7, and LU-2220N-7

Walking Foot

Presser Foot

10711653 10711752 10711851 10711950 ø3 10745354 ø3 10746352 10712354 10712057

ø4 10745453 ø4 10746451

ø5 10745552 ø5 10746550

ø6 10745651 ø6 10746659

10712552

10758456

10712651

10712750

10712859

10712958

ø 3 10747350

ø 4 10747459

ø 5 10747558

ø 6 10747657

10713055

Standard

For overlapped sec-tions of material* To be used both

for flat and over-lapped sections.The medium typeb e t w e e n10712552 and10712651.

For overlapped sec-tions of material* To be used whenthe material is notfed smoothly intothe overlappedsections.

For l ight-weightsponge* To be used whenthe material is notfed smoothly intothe overlappedsections.

Right-single-sidedfoot* To be used when

sewing the edgesof a material.

Right-single-sidedfoot* To be used when

sewing the edgesof a material.

Right-single-sidedfoot* To be used whensewing the edgesof a material.

For piping* To be used in gen-

eral piping pro-cess.

For piping* The needle posi-tion with respect tothe pipe can beadjusted.

Adjustable

Wide type* To be used when

the material is notfed smoothly.d.

N o n - g r o o v etype

– 115 –

Feed dog: For LU-2210N/W-7 and LU-2212N-7

10717106 10717205 10717304 10739001

Standard Without groove For thin threads. Wide typeTo be used when the needlethread and the bobbin threaddo not smoothly interlace witheach other at the start of sewing.

3.3mm

2.2mm

3.3mm

1.6mm2.2mm 2.2mm

2.5mm 3.3mm

Throat Plate

10701704 10702009 40058071

Standard Wide type Only for LU-2220N-7

For machininga

10712255 10748358 10713253

Feeding foot for machining Presser foot B for machining Presser foot A for machining

MAH152010A0 Handing Ruler

6mm

5mm

8mm

19.4mm

4.5mm

3mm

11.9mm

23mm5mm8mm

10mm14mm

10735868Fixing mountbase (asm.)

Feed dog: For LU-2220N-7

40058070 40062827 40064353

Standard For thick threads For thin threads

Groove width: (1.0mm) Groove width (1.9mm) Groove width (1.0mm)

2.2m

m

3.3mm

2.2m

m

3.3mm

1.6m

m

2.5mm

– 116 –

(2) For LU-2260N/W-7

Set No. Needle Stopper Thread Guide Feed Dog Presser Foot (Assembly) Finger Guard Walking Foot (Assembly) Throat Plate Slide Plate (Left) Slide Plate (Right)

(4) 10784551 10777555 10779007 10780005 10781557 10786903 10783058 10784502 10786309 10701803

6 10784650 10777654 10779007 10780104 10781656 10786903 10783157 10784601 10786309 10781803

8 10784759 10777753 10779007 10780203 10781755 10786903 10783256 10784700 10786309 10701803

10 10784858 10777852 10779007 10780302 10781854 10787000 10783355 10784809 10786408 10786002

12 10784957 10777951 10779106 10780401 10781953 10787000 10783454 10784908 10786408 10786002

(14) 10785053 10778058 10779106 10780500 10782050 10787109 10783553 10785004 10786408 10786002

(16) 10785152 10778157 10779106 10780609 10782159 10787109 10783652 10785103 10786408 10786002

(18) 10785251 10778256 10779106 10780708 10782258 10787109 10783751 10785202 10786408 10786002

20 10783350 10778355 B1403526000 10780807 10782357 10787208 10783850 10785301 10786507 10786101

(22) 10785459 10778454 B1403526000 10780906 10782456 10787208 10783959 10785400 10786507 10786101

(24) 10785558 10778553 B1403526000 10781003 10782555 10787208 10784056 10785509 10786507 10786161

(30) 10785657 10778652 B1403526000 10781102 10782654 10787307 10784155 10785608 10786507 10786101

(36) 10785756 10778751 B1403526000 10781201 10782753 10787406 10784254 10785707 10786606 10786200

Max. Stich length = 6mm

(Cautions) 1. The set, including the needle width with parentheses ( ), are made to special order.2. The slide plates (left and right) are not included in the set.

SS8080410TP SS6060440TP

SS8080410TP SS5060310SP

Needle Width

– 117 –

13.Machine head wiring (with thread trimmer only)(1) Connector from the machine head

(LU-2210N/W-7, LU-2260N/W-7 (other than LU-22*0*-0-*-0B)

Pin No. Function

1 Thread trimming (–)

2 Thread tension release (–)

3 +12V

4

5 DL Limit2 & Speed Limit

6 GND

7 Thread trimming (+)

8 Thread tension release (+)

9

10

11

12 Earth

• 12-pin connector

Pin No. Function

1 BT SW

2 NU SW

3 DL SW

4 DL DR

5 DL (–)

6 2P (–)

7 BT (–)

8 FL (–)

9 GND

10 RBT SW

11

12 +24V

13 DL, BT (+)

14

15 2P (+)

16 FL (+)

• 16-pin connector (4-gang switch)

(2) Connector from solenoid valve (asm.) (40024969)(LU-2210N/W-7, LU-2260N/W-7 (other than LU-22*0*-0-*-0B)

Pin No. Function

1 DL (–)

2 FL (–)

3 BT (–)

4

5

6

7 FL (+)

8 DL, BT (+)

9

10


– 118 –

(3) Connector from the machine head(For LU-2210N/W-7, LU-2260N/W-7 (LU-22*0*-0-*-0B)

Pin No. Function



3

4

5

6



9

10

11

12 Earth


Pin No. Function

1 BT SW

2 NU SW

3

4

5 DL (–)

6 2P (–)

7 BT (–)

8 FL (–)

9 GND

10 RBT SW

11

12

13 DL, BT (+)

14

15 2P (+)

16 FL (+)


(4) Connector from solenoid valve (asm.) (40025724)(For LU-2210N/W-7, LU-2260N/W-7 (LU-22*0*-0-*-0B)

Pin No. Function

1

2 FL (–)

3 BT (–)

4

5

6

7 FL (+)

8 BT (+)

9

10


– 119 –

(5) Connector from the machine head(LU-2212N-7)

Pin No. Function



3 +12V

4


6 GND



9

10

11

12 Earth


Pin No. Function

1 BT SW

2 NU SW

3 DL SW

4 DL LED (–)

5 DL (–)

6 2P (–)

7 BT (–)

8 FL (–)

9 GND

10

11 2P SW

12 +24V

13 DL, BT (+)

14 2P LED (–)

15 2P (+)

16 FL (+)


(6) Connector from solenoid valve (asm.) (40025981)(LU-2212N-7)

Pin No. Function

1 DL (–)

2 FL (–)

3 BT (–)

4 2P (–)

5

6 DL, BT (+)

7 FL (+)

8

9 2P (+)

10


– 120 –

(7) Connector from the machine head(LU-2220N-7)

Pin No. Function

1

2 Thread tension release (-)

3 +12V

4


6 GND

7


9

10

11

12 Earth


Pin No. Function

1 BT SW

2 NU SW

3 DL SW

4 DL LED (–)

5 DL (–)

6 2P (–)

7 BT (–)

8 FL (–)

9 GND

10 RBT SW

11 2P SW

12 DL LED (+)

13 DL, BT (+)

14

15 2P (+)

16 FL (+)


(8) Connector from solenoid valve (asm.) (40063828)(LU-2220N-7)

Pin No. Function

1 DL (–)

2 FL (–)

3 BT (–)

4 2P (–)

5

6 DL (+)

7 FL (+)

8 BT (+)

9 2P (+)

10


Pin No. Function

1 Needle thread clamp device SW

2 GND

3

4

• 4-pin connector (Needle thread clamp switch)

Pin No. Function


2 Thread trimmer return (–)

3 Condensation (–)

4 Needle thread clamp (–)

5 FL2 (–)

6

7


9 Thread trimmer return (+)

10 Condensation (+)

11 Needle thread clamp (+)

12 FL2 (+)

13

14

• 14-pin connector (Blue)

14. Timing Chart

– 121 –

LU-2210N/W-7, LU-2260N/W-7, LU-2212N-7 SC-510 timing chart

LU-2220N-7 SC-510 timing chart

DOWN stop range (K)

DOWN stop range (K)DOWN stop range (K)

Reverse revolution (B)

Reverse revolution (B)

UP stop range (E-F)

UP stop range (E-F)UP stop range (E-F)

Main shaft angle

Main shaft angle

130° 12° 65° 75°

120° 160° 60° 100°SY-2 detection DOWN stop detection

DOWN stop detection

UP stop detection

UP stop detection

120° 155°Needle thread trimmer

Needle thread trimmer

ON

290° 60° (Start of UP stop detection)

60° (Start of UP stop detection)

Tension release

Needle thread trimmer

Tension release

Tension release

ON

160° 195°ON

0° 60° (Start of UP stop detection)ON

130° 65° 75° 130° 12° 65° 75°

120° 160° 60° 100°

230°OFF ON

30°OFF ON

120°Condensation OFF ON

Thread trimmer return ON OFF ON

35°

130°

35°

60°

190°

20ms

10ms

LU-2210N-7LU-2260N-7

LU-2212N-7

(End of DOWN stop detection)

15. Table Dimension Diagram

– 122 –

50 40 30 20 10 0 10 20 30

50 0 30

(Drill a hole at the time of set-up).

4-ø3.4 depth 10

Drawer stopper installing position(On the bottom surface)

4-ø3.5, depth 10(On the bottom surface)

18 drilled holeswith depth of 30

Surface C1.5,chamfered

18 drilled

(Drill a hole at the time of set-up).

*3.5, depth 10 2-ø3.4, depth 10(On the bottom surface)

2-ø3.5, depth 10

358

(For

T ty

pe s

tand

)

380

(For

Z ty

pe s

tand

)

Logo designated by JUKI(using supplied block print)

ø6, depth 10 (On the bottom surface)

Detailed Dimension Drawing (2:1)

Style of type: Helvetics Reg. Condensed: Voided letters

Thickness: 1.5

Thickness: 0.8

Thickness: 0.5

Thickness: 1.5

3-ø13 drilled hole

Part No. : 10735306

®

MARKETING & SALES H.Q.8-2-1, KOKURYO-CHO,CHOFU-SHI, TOKYO 182-8655, JAPANPHONE : (81)3-3480-2357 • 2358FAX : (81)3-3430-4909

Copyright © 2007 JUKI CORPORATION.

All rights reserved throughout the world.

Please do not hesitate to contact our distributors or agents in your area for further information when necessary.* The description covered in this engineer's manual is subject to change for improvement of the

commodity without notice.07 · 11 Printed in Japan (E)

This manual uses environment-friendly soyink.

Juki Corporation operates an environmental management system topromote and conduct the following as the company engages in theresearch, development, design, sales, distribution,and maintenanceof industrial sewing machines, household sewing machines, industrialrobots, etc., and in the provision of sales and maintenance servicesfor data entry systems:1 The development of products and engineering processes that are

safe to the environment2 Green procurement and green purchasing3 Energy conservation (reduction in carbon-dioxide emissions)4 Resource saving (reduction of papers purchased, etc.)5 Reduction and recycling of waste6 Improvement of logistics efficiency (modal shift and improvement

of packaging, packing, etc.)

2- needle, high-speed, unison-feed …lu-2212,lu-2220 em.pdf29227501 no.e306-04 engineer’s manual...

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