acme yo-yo company
DESCRIPTION
Acme Yo-yo Company. Omar Hernandez, Alex Slocum, Jr. – Yo-Yo Base. Dayan Paez – Clear Cover and Snap-fit retaining ring. Kimberlee Collins & Rosa Rodriguez - Wiley Cover. Assembly. Base Optimization. Optimization Order Shot size Cool Time Hold Size –Sprue-break Results: SS: 3.25 in - PowerPoint PPT PresentationTRANSCRIPT
Acme Yo-yo CompanyAcme Yo-yo Company
Omar Hernandez, Alex Slocum, Jr. –
Yo-Yo Base
Kimberlee Collins & Rosa Rodriguez -
Wiley Cover
Dayan Paez – Clear Cover and Snap-fit
retaining ring
Assembly
Base OptimizationOptimization Order
– Shot size– Cool Time– Hold Size –Sprue-
break
Results:– SS: 3.25 in– HT: 60 sec– CT: 90 sec
Cycle time– 100 sec
Distribution of snap diameter for entire production
0
5
10
15
20
25
30
35
40
2.351 2.3568 2.3626 2.3684 2.3742 2.38 More
Diameter (in)
Shewhart Control Chart w ith LCL and UCL (at 2 Std. Dev)
2.360
2.365
2.370
2.375
2.380
2.385
0 2 4 6 8 10
Data Point
Ave
rag
e
Base Process Details
• Process capacity– Cp = .298
• Higher since actual tolerances spec range is greater than 0.005 in.
• Cycle Time– 100 seconds, steady state
• Production– 125 bases producted
• Some got stuck on mold• Several short shots.
Conclusion
• Rate: very difficult to increase.• Problems:
– Cooling Time.– 1st generation mold was too big.
• Flexibility– Geometry: limited
• Cooling time– Color: whatever was in the hopper.
• Cost: relatively high due to low rate/large part size.• Ways quality can be increased:
– Draft angles– MoldFlow™– Address uneven cooling
Wiley CenterpieceWiley Centerpiece
Injection Molding Piece by Rosa Rodriguez and Kimberlee Collins
InspirationCan you find him???
Drawing
Optimization
Order– Shot size– Hold time– Cool time
Results– SS: 0.62 in– HT: 5 sec– CT: 9 sec
“Cycle time”– 15 sec on
automatic
Diameter vs. Cooling Time
1.685
1.686
1.687
1.688
1.689
1.69
1.691
1.692
1.693
1.694
0 2 4 6 8 10 12 14 16
Time (s)
Sn
ap
Fit
Dia
me
ter
(in
)
cooling time hold time
Production
Production Run by Settings
1.678
1.68
1.682
1.684
1.686
1.688
1.69
0 20 40 60 80 100 120
Part No.
Sn
ap
Fit
Dia
me
ter
[in
]
1-80 1-80 avg80-134 80-134 avg
Distribution of Diameters Before and After Shift
0
5
10
15
20
25
30
1.679 1.68 1.681 1.682 1.683 1.684 1.685 1.686 1.687 1.688
Snap Fit Diameter [in]
Fre
qu
en
y
before shift after shift
• Process capacity– Cp = 8.33
• Cycle Time– 8 seconds, steady state
• Number produced– 133 parts, of 3 distinct colors
Shewart Control Chart withLCL and UCL (at 3 Std.Dev.)
1.676
1.678
1.68
1.682
1.684
1.686
1.688
1 2 3 4 5 6 7 8 9 10 11 12 13 14
Data Point
Ave
rag
e
Conclusion
• Rate: hard to increase without another machine (2 at a time)
• Flexibility– Geometry: limited
• Cool time
– Color: great
• Cost: low due to small volume• Quality: using a ball end mill, the core finish
could be improved; avoid clear plastic
Retaining RingRetaining Ring
Injection Molding by Dayán Páez
Drawing
Optimization
Order– Shot size– Hold time– Cool time
Results– SS: 0.70 in– HT: 3 sec– CT: 3 sec
“Cycle time”– 8 sec on
automatic
Snap Fit Diameter vs. IM Parameters
2.345
2.350
2.355
2.360
2.365
2.370
2.375
2.380
2.385
2.390
0 5 10 15 20
Time (s)
Sn
ap
Fit
Dia
me
ter
(in
)
Cool Time Hold Time
Average (in) for Snap Fit Diameter
2.320
2.330
2.340
2.350
2.360
2.370
2.380
2.390
2.400
A B C D E F G
Batch #
Dim
ensi
on
(in
)
Average (in) Target Low er Tol. Limit
Process Details
• Process capacity– Cp = .307
• Higher since actual tolerances spec range is greater than 0.005 in.
• Cycle Time– 8 seconds, steady state
• Number produced– 200 parts, of 5 distinct colors
Conclusion
• Rate: hard to increase without a bigger machine (2 at a time)
• Flexibility– Geometry: limited
• Cool time
– Color: great
• Cost: low due to small volume• Quality: can be increased through use
of proper equipment (e.g. CNC Lathe)
Clear CoverClear Cover
Thermoform by Dayán Páez
Drawing
Optimization
Criteria: visual quality
Order– Form time– Varied between temperature and heat time.
Results– Heat time: 30 sec– Form time: 15 sec– Temperature: 575 °F
“Cycle time”– ~60 sec in steady state
Process Details
• Process capacity– Cp = 4.71 (!)
• High due to flexibility in spec range.
• Cycle Time– 60 seconds, steady state
• Number produced– 100 parts at 1% error
Conclusion
• Rate: can best be increased by doing more at a time.
• Flexibility– Plastic thickness: limited to ≤ 0.030 in
• Cost: low due to small error rate
• Quality: heavily dependent on operator
Overall
• Integration of parts– Tight snap fit
• Assembly: 50 yoyos
• Functionality– Stable