EC Timer Box Product Design for Six Sigma

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Leo Neal
5 years ago
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1 EC Timer Box Product Design for Six Sigma

2 Application of Product Customers: Whirlpool, Bosch, AEG, and others 2

3 Goals To Decrease the reject rate by a factor of 10 from 10% to less than 1% 3

4 Test machine Layer Stacker Test cam Contact springs 4

5 Gage R&R on Automatic test Rig Attempt 1 Gage R&R (ANOVA) for Value Xbar Chart Gage name: Date of study: Reported by: Tolerance: Misc: Automatic Test rig 22/09/98 Switchbox team 0.5mm Test on switch 1a level 1 By Part SL=23.46 Sample Mean X= SL= Part Part R Chart Components of Variation %Total Var %Study Var %Toler Sample Range SL= R= Percent SL= Part Gage R&R Part-to-Part 5

6 To Make a Long Story Short. Team determined that the test was failing good units. Determined failures were related to rotation speed of the cam 6

7 Effect of test rotation speed on radius rejects Current operating speed Chi-Square Test Expected counts are printed below observed counts Test1 Test2 Total proportion of parts retested & radius rejects Speed Total CONCLUSION: WITH THE CAM ROTATION SPEED OF 70000, FALSE REJECTS CAN BE REDUCED BY A FACTOR OF 10 Chi-Sq = = DF = 5, P-Value =

8 However. We were failing our suppliers for perceived Variation on Critical Dimensions. Process Capability Analysis for A1=29,4 Process Capability Analysis for A1=29,4 Process Capability Analysis for B1=24,5 Process Data Process Data 29, ,4500 Target Target 29, ,3500 Mean 29,5305 Mean 29,5305 Sample N 30 Sample N 30 StDev (ST) 0, StDev (ST) 0, StDev (LT) 0, StDev (LT) 0, ST ST LT LT Process Data 24,5500 Target 24,4500 Mean 24,4229 Sample N 30 StDev (ST) 0, StDev (LT) 0, ST LT Potential (ST) Capability Potential (ST) Capability Cp 0,52 Cp 0,52 CPU -0,84 CPU -0,84 CPL 1,89 CPL 1,89 Cpk -0,84 Cpk -0,84 Cpm Cpm 29,35 29,40 29,45 29,50 29,55 29,60 29,35 29,40 29,45 29,50 29,55 29,60 Potential (ST) Capability Cp 0,67 CPU 1,70 CPL -0,36 Cpk -0,36 Cpm 24,35 24,40 24,45 24,50 24,55 Overall (LT) Capability Observed Performance Expected ST Performance Expected LT Performance Overall (LT) Capability Observed Performance Expected ST Performance Expected LT Performance Pp 0,58 PPM < 0,00 PPM < 0,01 PPM < 0,00 Pp 0,58 PPM < 0,00 PPM < 0,01 PPM < 0,00 PPU -0,94 PPM > ,00 PPM > ,00 PPM > ,74 PPU -0,94 PPM > ,00 PPM > ,00 PPM > ,74 PPL 2,10 PPM Total ,00 PPM Total ,00 PPM Total ,74 PPL 2,10 PPM Total ,00 PPM Total ,00 PPM Total ,74 Ppk -0,94 Ppk -0,94 Mean =29.53 Stdev.= Overall (LT) Capability Observed Performance Expected ST Performance Expected LT Performance Pp 0,73 PPM < ,33 PPM < ,33 PPM < ,65 PPU 1,85 PPM > 0,00 PPM > 0,18 PPM > 0,01 PPL -0,39 PPM Total ,33 PPM Total ,50 PPM Total ,66 Ppk -0,39 Mean = Stdev.= Process Capability Analysis for C1=23,4 Process Capability Analysis for D1=14,1 Process Data 23,4500 Target 23,3500 ST LT Process Data 14,1500 Target 14,0500 ST LT Mean 23,4547 Mean 14,1502 Sample N 30 Sample N 30 StDev (ST) 0, StDev (ST) 0, StDev (LT) 0, StDev (LT) 0, Potential (ST) Capability Potential (ST) Capability Cp 1,63 Cp 0,94 CPU -0,15 CPU -0,00 CPL 3,42 CPL 1,88 Cpk -0,15 Cpk -0,00 Cpm 23,35 23,37 23,39 23,41 23,43 23,45 23,47 23,49 Cpm 14,05 14,07 14,09 14,11 14,13 14,15 14,17 14,19 14,21 Overall (LT) Capability Observed Performance Expected ST Performance Expected LT Performance Pp 1,47 PPM < 0,00 PPM < 0,00 PPM < 0,00 PPU -0,14 PPM > ,00 PPM > ,82 PPM > ,02 PPL 3,08 PPM Total ,00 PPM Total ,82 PPM Total ,02 Ppk -0,14 Mean = Stdev.= Overall (LT) Capability Observed Performance Expected ST Performance Expected LT Performance Pp 1,05 PPM < 0,00 PPM < 0,01 PPM < 0,00 PPU -0,00 PPM > ,67 PPM > ,00 PPM > ,53 PPL 2,11 PPM Total ,67 PPM Total ,01 PPM Total ,53 Ppk -0,00 Mean =15.15 Stdev.=

9 Tolerance Analysis Was Needed on the CAM Cam R (45.109) (18.791) (spring pad)

10 Statistical Tolerancing Statistical Tolerancing was performed on the switch, considering all sources of variation in the supply chain The following distribution was calculated Forecast: Open Switch (1b) Postulated 5,000 Trials Frequency Chart 26 Outliers mm 10

11 Compared to the Specification for an Open We were WAY inside the performance parameters required We were scrapping supplier material against unrealistic specs σ = mm Z =( )/0.016 = 0.297/.016 = mm μ = mm mm 11

12 Which allowed. The Company was able to qualify a new supplier for $700k a year savings. The team had previously disqualified this supplier for not meeting specs. Until the Six Sigma team determined that current suppliers failed to meet the same specs and actually had more variation Why? Because the specs did not match customer expectations. 12

Eliminate Coil Wire Breakage on Passive Anti-Theft System (PATS)

Eliminate Coil Wire Breakage on Passive Anti-Theft System (PATS) 1 Six Sigma Team Passive Anti-Theft System Black Belt Candidate: Sam. H. OEM Master Black Belt: Tom R. OEM Project Champion: Greg B. - OEM