02 transmission system lg933l

Training course for LG933LTraining course for LG933LTraining course for LG933LTraining course for LG933L

Chapter 3 Torque converter & gearbox

Section 1Section 1Section 1Section 1 Overview of C&T Overview of C&T Overview of C&T Overview of C&T

Section 2 Torque converterSection 2 Torque converterSection 2 Torque converterSection 2 Torque converter

Overview

Structure

Operating principle

Oil-way

Section 4 Guidelines for assembly Section 4 Guidelines for assembly Section 4 Guidelines for assembly Section 4 Guidelines for assembly

and operationand operationand operationand operation

Chapter 3 Torque converter & gearbox

Section 5 MaintenanceSection 5 MaintenanceSection 5 MaintenanceSection 5 Maintenance for gearboxfor gearboxfor gearboxfor gearbox

Section 6 Common faults and Section 6 Common faults and Section 6 Common faults and Section 6 Common faults and

troubleshooting troubleshooting troubleshooting troubleshooting

Section 3 GearboxSection 3 GearboxSection 3 GearboxSection 3 Gearbox

RELIABILITY IN ACTION


Overview

BYD4208 gearbox

Structure

Section 1Section 1Section 1Section 1 Overview of C&T Overview of C&T Overview of C&T Overview of C&T

All parts(including torque converter, All parts(including torque converter, gearbox, drive shaft) between power gearbox, drive shaft) between power device(engine) and drive device(axle) device(engine) and drive device(axle) of construction equipment are called of construction equipment are called drive system. drive system.

RELIABILITY IN ACTION2


1.Overview 1.Overview LG933L adopts YJ315LGLG933L adopts YJ315LG--11 hydraulic hydraulic torque converter. torque converter.



2.Structure2.StructureThe basic hydraulic torque converter The basic hydraulic torque converter is mainly composed of pump impeller is mainly composed of pump impeller 1, guide wheel 2 and turbine 3, and 1, guide wheel 2 and turbine 3, and the sealed annular working chamber the sealed annular working chamber formed by said components is the formed by said components is the circulation passage of the working circulation passage of the working fluid. The shape of the working fluid. The shape of the working chamber within the cross section cut chamber within the cross section cut by revolving axis (namely, the axial by revolving axis (namely, the axial surface) is called a circulation circle. surface) is called a circulation circle.


The circulation circle of the torque The circulation circle of the torque converter forms to completely converter forms to completely symmetrical part by taking rotating symmetrical part by taking rotating shaft as centre line. The largest shaft as centre line. The largest diameter of the portion passed by the diameter of the portion passed by the working fluid in the circulation circle working fluid in the circulation circle is called the effective diameter of the is called the effective diameter of the circulation circle.circulation circle.


2.Torque converter operating principleDuring operation of the hydraulic torque converter, the engine drives the pump impeller to rotate, and the torque of the engine is exerted to the pump impeller. The working fluid in the pump impeller is driven to rotate by the blades of the pump impeller during rotation. The fluid performs circular motion around the axis of circular motion (called transport


circular motion (called transport motion) while executes relative motion from the inner edge of the blade to the outer edge thereof along the passage among the blades, and combination of the two motions forms absolute motion; meanwhile, the pressure on the outer edge of the pump impeller is higher and on the inner edge is lower, the difference of which depends on the radius and rotation speed of the pump impeller.


The working fluid bears the effect of blades of pump impeller and gains certain kinetic energy and pressure energy when departing the pump impeller so as to convert the generated mechanical energy into fluid energy of working fluid (kinetic energy and pressure energy).


he high-speed oil flow from the pump impeller enters the turbine 3 through a blade-free area from by housing wheel and impacts the turbine blades to rotate the turbine and enable the turbine shaft to obtain certain torque for overcoming the external resistance and starting work .


While changing the momentum moment of the fluid, the guide wheel further changes the energy form of the fluid, namely, the transition from the pressure energy of the fluid into the kinetic energy thereof, or the converse transition. Generally speaking, it changes the pressure


energy of the fluid into kinetic energy.


Power from torque converter is Power from torque converter is transmitted to gearbox through drive transmitted to gearbox through drive shaft. shaft.

11--drive shaft drive shaft


1


4.Oil4.Oilway way oiloil--way structure of speedway structure of speed--control control pumppump

11--temperature sensortemperature sensor22--inlet oil pipe of radiator for drive oilinlet oil pipe of radiator for drive oil33--inlet oil pipe of speedinlet oil pipe of speed--control pumpcontrol pump44--oil filteroil filter

1 2

3

6


55--pipe between pump and filterpipe between pump and filter66--speedspeed--control pumpcontrol pump

4

5


4.Oil4.Oilway way oiloil--way structure of working pumpway structure of working pump

11--inlet oil pipe of torque inlet oil pipe of torque converter(belonging to oilconverter(belonging to oil--way way structure of speedstructure of speed--control pump)control pump)22--working pumpworking pump33--inlet oil pipe of working pumpinlet oil pipe of working pump

1 2


44--outlet oil pipe of working pumpoutlet oil pipe of working pump

3

4


1.Overview 1.Overview A. Function of gearboxA. Function of gearbox. reduce the speed and increase . reduce the speed and increase the torquethe torque. Make the loader have a good . Make the loader have a good selfself--adaptabilityadaptability.realize neutral, make it easy to .realize neutral, make it easy to start and stop when engine is start and stop when engine is


workingworking.working with torque converter, and .working with torque converter, and enlarge the range of output power enlarge the range of output power and speedand speed. Enable loader backward . Enable loader backward movement .movement .


B. Classification of gearboxB. Classification of gearboxAccording to Control Mode:According to Control Mode:. Power Shifting Gearbox . Power Shifting Gearbox . Manual Shift Gearbox . Manual Shift Gearbox .Auto shift gearbox. .Auto shift gearbox.

Power Shifting Gearbox concludePower Shifting Gearbox conclude. Axis. Axis--fixed Gearbox fixed Gearbox


. Planetary Gearbox. Planetary Gearbox


2.BYD4208 gearbox2.BYD4208 gearboxAAType Type BYD4208 is AxisBYD4208 is Axis--fixed, constant fixed, constant mesh, hydraulic or shift fork gearbox. mesh, hydraulic or shift fork gearbox. B.FeatureB.Feature

Simple and compact structure, Simple and compact structure, Reliable work, convenient operation, Reliable work, convenient operation, high transmission efficiency and long high transmission efficiency and long


serve life. serve life.


3.Structure 3.Structure Main structure of BYD4208 as Main structure of BYD4208 as followingfollowing11--reverse shaft assemblyreverse shaft assembly22--input shaft assemblyinput shaft assembly33--middle shaft assemblymiddle shaft assembly44--output shaft assemblyoutput shaft assembly55--shift fork shaft shift fork shaft

1

2

3

9

8

7


66--shift forkshift fork77--clutch of gear IIclutch of gear II88--clutch of gear I clutch of gear I 99--clutch of reverse gearclutch of reverse gear

4

5

6


AAclutch clutch

structure structure

All clutch of this gearbox are same All clutch of this gearbox are same basically as shown in right figure:basically as shown in right figure:11--shaftshaft 22--shellshell33--pistonpiston 44--driving discdriving disc55--driven discdriven disc 66--springspring77--ball ball 88--oil channel oil channel

12

13

15


99--driven gear driven gear 1010--seal ringseal ring1111--piston ring 12piston ring 12-- valve platevalve plate1313--oil port for lubricating oil 14oil port for lubricating oil 14--bearing bearing 1515--driving geardriving gear

14


working principle working principle When no pressure oil flows into When no pressure oil flows into cylinder, there is a small space cylinder, there is a small space between driven disc and driving disc, between driven disc and driving disc, so all disc keep their state of motion; so all disc keep their state of motion; when pressure oil flows into the when pressure oil flows into the cylinder of clutch, the piston is cylinder of clutch, the piston is pushed left to make all discs hug pushed left to make all discs hug

12

13

15


tightly and rotate in the state of tightly and rotate in the state of driving disc; when the pressure oil is driving disc; when the pressure oil is cut off, the piston return at the action cut off, the piston return at the action of the springs, and meanwhile of the springs, and meanwhile release all discs. release all discs.

14


Clutch assembly of gear IClutch assembly of gear IClutch assembly of gear I is fixed on Clutch assembly of gear I is fixed on input shaft. input shaft.



Clutch assembly of gear IIClutch assembly of gear IIClutch assembly of gear IIClutch assembly of gear II is fixed on is fixed on the middle shaftthe middle shaft. .



Clutch assembly of reverse gearClutch assembly of reverse gearClutch assembly of reverse gear is Clutch assembly of reverse gear is fixed in shaft of reverse gear. fixed in shaft of reverse gear.



B. The arrangement of all shaft B. The arrangement of all shaft assembly in the gearboxassembly in the gearbox

11--input shaft assemblyinput shaft assembly22--reverse gear shaft assemblyreverse gear shaft assembly33--middle shaft assemblymiddle shaft assembly44--output shaft assemblyoutput shaft assembly

1

2


2

3

4


C. Output shaft assemblyC. Output shaft assemblyformationformation11--rear output flangerear output flange22--rear cover of output shaftrear cover of output shaft33--PP bearingbearing44--sliding bearing sliding bearing 55--highhigh--speed output gearspeed output gear66--sliding sleevesliding sleeve

1 2 3 4 5 6 7 8


77--output shaftoutput shaft88--lowlow--speed output gearspeed output gear


shifting fork mechanism assemblyshifting fork mechanism assembly

11--shifting forkshifting fork22--paper spacerpaper spacer33--shifting fork bracketshifting fork bracket44--shifting fork shaftshifting fork shaft


1 2 3 4


operating principleoperating principleThe sliding bearings 1 cause gear 2 The sliding bearings 1 cause gear 2 and 4 move relative to the shaft 3. and 4 move relative to the shaft 3. Gear 2 and 4 have same modules as Gear 2 and 4 have same modules as gear in the shaft 3. and they can gear in the shaft 3. and they can mesh tightly with sliding sleeve 5. mesh tightly with sliding sleeve 5. Shifting fork 6 gets stuck in the Shifting fork 6 gets stuck in the shifting fork groove in the sliding shifting fork groove in the sliding

1 2 3 4


sleeve. sleeve.

There is a highThere is a high--low speed control rod, low speed control rod, and this rod control the shift fork 6 and this rod control the shift fork 6 through the shaft 7 and make it can through the shaft 7 and make it can move in a certain range.move in a certain range.

7 6 5


When sliding sleeve meshes with When sliding sleeve meshes with gears in the boss of the gear 2 and gears in the boss of the gear 2 and gears in the shaft 3, the wheel loader gears in the shaft 3, the wheel loader drives at high speed. When sliding drives at high speed. When sliding sleeve meshes with gears in the boss sleeve meshes with gears in the boss of the gear4 and gear in the shaft 3, of the gear4 and gear in the shaft 3, the wheel loader drives at low speed.the wheel loader drives at low speed.

1 2 3 4


7 6 5


DDtransmission line transmission line

forward gear Iforward gear I

Transmission line as followingTransmission line as following



forward gear IIforward gear II




forward gear IIIforward gear III




forward gear IVforward gear IV




reverse gear Ireverse gear I




reverse gear IIreverse gear II




E. SpeedE. Speed--control valvecontrol valveSpeedSpeed--control valve is the device control valve is the device which controls the direction of which controls the direction of pressure oil and control the motion of pressure oil and control the motion of the clutch making the vehicle drive at the clutch making the vehicle drive at the speed and in the condition you the speed and in the condition you choose. choose.

1


FormationFormation

11--sealantsealant

22--core of the speedcore of the speed--control valvecontrol valve33--valve bodyvalve body44--paper washerpaper washer55--cutting valvecutting valve66--bottom platebottom plate77--paper washerpaper washer88--gear positioning devicegear positioning device

1

2

3

4

5 6 7 8


Arrangement of oil ports in the Arrangement of oil ports in the speedspeed--control valvecontrol valveCavity A is links with oil inlet(oil inlet is Cavity A is links with oil inlet(oil inlet is links with combined valve of torque links with combined valve of torque converter). converter). Cavity B links with oil passage of Cavity B links with oil passage of speedspeed--control valve control valve Cavity D links to the clutch of gear I Cavity D links to the clutch of gear I

CCCC CCCCCCCCD

B

F E


Cavity E links to the clutch of gear II Cavity E links to the clutch of gear II Cavity F links t the clutch of reverse Cavity F links t the clutch of reverse gear gear

CCCC

A


Cutting valveCutting valvesparespareWhen the brake pedal is pressed When the brake pedal is pressed down, brake pressure air presses the down, brake pressure air presses the valve core of the cutting valve move, valve core of the cutting valve move, and cuts the passage between cavity and cuts the passage between cavity A and B, so the pressure oil cant A and B, so the pressure oil cant flow into speedflow into speed--control oil passage, control oil passage, therefore there is no power output. therefore there is no power output.

CCCC CCCCCCCCD

B

A

F E


CCCC

Clutch of gear II

Clutch of gear IIClutch of gear II

Clutch of gear II Clutch of reverse gear

Clutch of reverse gearClutch of reverse gear

Clutch of reverse gear

Clutch of gear I

Clutch of gear IClutch of gear I

Clutch of gear I


SpeedSpeed--control control schematic diagramschematic diagram

11--filterfilter22--speedspeed--control valvecontrol valve33--speedspeed--control pressure selective control pressure selective valvevalve

44--pressure limit valve of outletpressure limit valve of outlet55--pressure limit valve of inletpressure limit valve of inlet


66--speedspeed--control valvecontrol valve77--cutting valvecutting valve

Section 4 Guidelines for Section 4 Guidelines for Section 4 Guidelines for Section 4 Guidelines for

assembly and operationassembly and operationassembly and operationassembly and operation

1.1. Notes for assemblyNotes for assembly

A. End cover of gear II cant change A. End cover of gear II cant change with it of gear I of reverse gear. with it of gear I of reverse gear.




B. Adjusting nut of clutch assembly B. Adjusting nut of clutch assembly




C. When assemble, you should C. When assemble, you should ensure the input shaft of gearbox and ensure the input shaft of gearbox and output shaft of torque converter output shaft of torque converter coaxial, same as the output shaft of coaxial, same as the output shaft of gearbox and input shaft of front and gearbox and input shaft of front and rear axle. rear axle.




2. Notes for operation2. Notes for operationA. You should pay attention to the A. You should pay attention to the pressure indictor of speedpressure indictor of speed--control oilcontrol oil1.21.2--1.5MPa1.5MPa and lubrication oiland lubrication oil0.150.15--0.30MPa0.30MPa at time, no at time, no condition of exceeding the range is condition of exceeding the range is permittedpermitted.




B. The speedB. The speed--control rod and even control rod and even the whole speedthe whole speed--control mechanism control mechanism should be flexible, no binding is should be flexible, no binding is permitted, position should be precise permitted, position should be precise when change gear.when change gear.

Scheme 1Scheme 1highhigh--low speedlow speed--control control mechanism.mechanism.


Scheme 2Scheme 2gear speedgear speed--control control mechanism.mechanism.

C. When the brake pedal is pressed C. When the brake pedal is pressed down, the vehicle mustnt drive even down, the vehicle mustnt drive even in condition of strongest power of the in condition of strongest power of the engine.engine.D. Hand brake mechanism should be D. Hand brake mechanism should be adjusted well to make sure its work adjusted well to make sure its work reliably. reliably.

Section 5 Maintenance for gearbox

Change the drive oil at time of the first 50hours use, and change again at 500hours use, Change the drive oil at time of the first 50hours use, and change again at 500hours use, from then on, change every 1000hours.from then on, change every 1000hours.

Clean the filter of drive oil at time of the first 50hours use, and from then on ,clean it every Clean the filter of drive oil at time of the first 50hours use, and from then on ,clean it every 500hours. Pay attention to that whether there is aluminum 500hours. Pay attention to that whether there is aluminum swarfswarf, copper , copper swarfswarf, iron , iron swarfswarfwhen change drive oil, so according to the result you can find whether C&T work well. If you when change drive oil, so according to the result you can find whether C&T work well. If you find copper find copper swarfswarf in the oil, you should check the gearbox, and if aluminum in the oil, you should check the gearbox, and if aluminum swarfswarf, check torque , check torque converter. converter.


Check whether the oil level is enough, whether there is abnormal noise in the gearbox, Check whether the oil level is enough, whether there is abnormal noise in the gearbox, whether the knots are loose, and whether there is leakage, check whether the temperature and whether the knots are loose, and whether there is leakage, check whether the temperature and pressure of drive oil in the normal range. pressure of drive oil in the normal range.

Section 6 Common faults and troubleshooting

11FailuresFailuresthe oil pressure is low excessivelythe oil pressure is low excessively even the pressure is zero. even the pressure is zero.

fault judgment and troubleshooting:fault judgment and troubleshooting:lack for oil, pump sucks air.lack for oil, pump sucks air.add oiladd oilblockage in filter.blockage in filter.clean or replace the filterclean or replace the filterfailure of the pump. (replace the pump)failure of the pump. (replace the pump)failure of the main pressure valve in adjuster valve.failure of the main pressure valve in adjuster valve.repair the speedrepair the speed--control pressure valvecontrol pressure valveleakage in speedleakage in speed--control valve.control valve.check, repair)check, repair)leakage as result of failure of seal of clutch or gasket ring in the end of shaft where there is oil inlet port.leakage as result of failure of seal of clutch or gasket ring in the end of shaft where there is oil inlet port.


replace gasket ringreplace gasket ringmiss of the ball of the onemiss of the ball of the one--way valve in the clutch.way valve in the clutch.


22 FailuresFailuresoil pressure is high excessively oil pressure is high excessively

fault judgment and troubleshooting:fault judgment and troubleshooting:failure of main adjuster valve in failure of main adjuster valve in pressure reducing valve.pressure reducing valve.check or repair)check or repair)something outside enters oilsomething outside enters oil--passage to make a blockage.(clean and rip it)passage to make a blockage.(clean and rip it)the oil is not fitthe oil is not fit((change the oil for standard oilchange the oil for standard oil) ) failure of the sensor of the pressure oil failure of the sensor of the pressure oil



33 FailuresFailuresoil temperature is high excessivelyoil temperature is high excessively

fault judgment and troubleshooting:fault judgment and troubleshooting:blockage in radiator (clean the radiatorblockage in radiator (clean the radiatorthere is some water in oil.there is some water in oil.check the pipe and replace the oil)check the pipe and replace the oil)lack for drive oil in the gearboxlack for drive oil in the gearboxadd oiladd oilthe gear is not suitable when working.the gear is not suitable when working.choose low gearchoose low gearhand brake is locked and return bragging seriously.(adjust the brake)hand brake is locked and return bragging seriously.(adjust the brake)


the discs cant part absolutely or they hug together.(replace the discs)the discs cant part absolutely or they hug together.(replace the discs)

02 transmission system lg933l

Documents

torque convertersection

torque converter forms

torque converter2

torque converter1

assembly section

cross section

overview lg933l

working circulation