1. Checkweigher Design Concept
All-Fill Inc.
Dan MacGuigan, Matt Griffith,
Phil Mitchell, Richard Maurer

2. Introduction of Project
Weighs Products
Quality Control
Rejects out-of-spec Products
Up to 200 products/min.

3. Improvement Objectives (Wants)
Decrease Cost
Material
Manufacturing/Machining Time
Assembly Time
Fewer Parts
Fewer Required Tools
Increase Marketability
Easier Maintenance
“Tool-less” Belt Changes
Drive Belt
Conveyor Belt
Faster Order Turnaround

4. Design Constraints Safety Weight Footprint Life
Protection From Moving Parts
Design Against Catastrophic Failure
Weight
Cannot Increase Overall Weight
Footprint
Cannot Change Current Footprint
Life
Service Life Cannot Decrease

5. Improvement Metrics Metric Current Target Achieved Material Cost
$290/$740
$230/$590
$220/$184
Manufacturing Time
18.5 hrs
14 hrs
10 hrs
Assembly Time
17 min
14 min
Number of Parts
86/208
75/100
80/99
# of Rollers 1 2
# of Tools Required
for Belt Change 3

6. How to Meet Wants Divide Checkweigher into Subsystems
Each Subsystem Offers Benefits
Some Subsystems Interrelated
Compounded Improvements

7. Identification of Subsystems
Motor Mount
Roller Attachment
Knife-Edge
Sidebars & Tie Bars
Current Design

8. Motor Mount Metric Current Target Achieved Time to Change Belt 7.3 min
Wants
Lower Cost (Benefits Sponsor)
Fewer Small Parts (Nuts, Washers, etc.)
Less Costly Manufacturing
Faster Assembly
Increase Marketability (Benefits Customer)
Easy Tensioning of Timing Belt
“Tool-less” / Fast Belt Change
Metric
Current
Target
Achieved
Time to Change Belt
7.3 min
5 min
3.3 min
Time to Properly Tension belt
2 min
1 min
0.5 min
# of Tools to Change Belt 3
Number of Parts 6 5 4

9. Motor Mount - Current

10. Motor Mount - New
Thumb Screw

11. Roller Integration Wants Lower Cost (Benefits Sponsor)
Lower Manufacturing Cost
Increased Marketability (Benefits Customer)
“Tool-less” Belt Change
More Versatile
Metric
Current
Target
Achieved
Time to Assemble
17 min
13 min
14 min
# of Rollers Types 1 2
# of Tools to Change Belt 3
Manufacturing Cost
$1110
$840
$600
In addition to talking about the wants and metrics listed on this slide, I plan to take a minute to talk about making

12. Roller Integration – Current
Roller Attachment Points
Current Attachment Points of Rollers

13. Roller Integration – New End Caps
Drive End Cap
Knife-Edge End Cap
Conventional Idler End Cap

14. End Cap Integration Snap Ring and Pliers
Make Sure You View in slideshow mode
Concept Roller Attachment Points
Cotter Pin

15. Knife-Edge Wants Lower Cost (Benefits Sponsor)
Simpler
Increased Marketability (Benefits Customer)
Less Vibration
Less Belt Wear
Shorter Transition Distance
Metric
Current
Target
Achieved
Time to Manufacture
7 hr
5 hr
3.7 hr
Material Cost
$740
$590
$184
# of Parts
208
100 99

16. Knife-Edge - Current Problems Many Small Parts Expensive
Nylon Spacer
Bearing
Problems
Many Small Parts
Expensive
Difficult to Assemble

17. Knife-Edge - New Material – PTFE (Teflon®) Few Parts
Low Coefficient of Friction
High Melting Temperature
Inexpensive
Few Parts

18. Sidebars & Tie Bars Wants Lower Cost (Benefits Sponsor)
Lower Material Cost
Shorter Manufacturing Time
End Cap Integration
Increased Marketability (Benefits Customer)
FDA Approved
Lighter
Metric
Current
Target
Achieved
Material Cost (per pair)
$20
$10 $6
Mass/Length
0.05 lbm/in
0.03 lbm/in
FDA Approved
Yes
Available

19. Sidebars - New Polycarbonate End Cap Integration Lighter
Less Expensive
Easily Machined
Sufficient Mechanical Properties
FDA Approved Available
End Cap Integration

20. Tie Bars - New
Redesigned for Compatibility with Polycarbonate Sidebars
Single Attachment to Sidebar
Material Change
From Aluminum to Polycarbonate
Less Costly
Lighter

21. Assembled Prototype

22. Testing Weight Assembly Time Maintenance Time Accuracy & Precision
Drive Belt Change
Conveyor Belt Change
Accuracy & Precision
Product Weight Measurements

23. Weight Current Weight New Weight 17.4% Weight Reduction 7lbs 4 ounces
Prototype

24. 18% Reduction In Assembly Time
Current
Prototype
Current Assembly
17 Minutes
4 Tools Needed
New Assembly
14 minutes
2 Tools Needed
18% Reduction In Assembly Time

25. Maintenance Time Conveyor Belt Change Time Increased
Due to Sidebar Material Change
Introduce Helicoils in Next Prototype
Drive Belt Change Time Decreased
Old Time: 7:30
New Time: 3:30
47% Decrease in Time Required
“Tool-less”
Less Hardware Required

26. Accuracy and Precision Testing
Sample Products Run on Actual Machine
Three Different Products
Representative of a Range of Weights
Three Conveyor Units Tested
Old Design
Conventional Prototype
Knife-Edge Prototype

27. Accuracy Results Offline Mass Compared to Data From: Old Design
Prototype of New Design
Prototype of New Design with Knife-edge

28. Precision Results
At Least 1 New Design Outperformed Current Checkweigher in Every Test

29. (60% of Current Checkweigher Cost) (~33% of Retail)
Overall Benefits
Tool-less Belt Change
Motor Mount
Cotter Pin
Lighter
Sidebars
Tie Bars
Fewer Parts
Knife-Edge
Versatile
End Caps
Knife-Edge
Sidebars
Less Expensive
Component
Money Saved
Motor Mount
$11
Knife-Edge
$480
Sidebar (2)
$14
Tie Bar (3)
$21
Manufacturing Time
$510
TOTAL SAVED: $1036
(60% of Current Checkweigher Cost) (~33% of Retail)

30. Conclusion Design Prototyping Testing Lighter More Versatile
Easier Maintenance
Less Expensive
Prototyping
Fully Functional Prototype
100% Scale
Testing
18% Assembly Time Reduction
“Tool-Less” Belt Changes
More Accurate
More Precise

31. Implementation Plan Provide to All-Fill:
Bill of Materials
Complete Electronic Drawing Package
Checkweigher Prototypes
Manufacture Three Complete Improved Checkweigher Designs
Run Mock Production Line

32. Questions Acknowledgements Nate Cloud Ha Dinh Ed White Dave Kendell
Steve Beard

33. BoM - Conventional Conventional Roller Quantity Hardware 6
1/4-20x1/2" Hex Socket Bolt 9
5-40x1/4" Flat Head Screw 2
1/4-20x1" Hex Socket Bolt
1/4-20 Washer
1/4-20 Lock Washer 4
1/4-20 Thumb Wheel
10-32x1" Hex Bolt
10-32 Washer
10-32 Lock Washer
10-32x1" Wing Bolt
10-32 Thumb Wheel
10-32x1/2" Hex Socket Bolt
Brass Washer (ID 3/8", OD .75")
Hairpin Cotter Pin (Wire Diameter = 0.1") 8
1/8"x1" Steel Dowel
Conventional Roller
Quantity
Part
Drawing Number 1
Motor with Sprocket
N/A
Motor Plate
MM1 2
Spacer
MM2
Motor Mount
MM3 3
Tie Bar S1
Sidebar S2
Drive End Cap
EC1
Idler End Cap
EC2
Idler Roller with Bearings
Drive Roller with Bearings and Sprocket
Roller Shaft S3
Table Top S4
Drive Belt
Conveyor Belt

34. Sidebar

35. Right End Cap (Knife-Edge)

36. Left End Cap (Knife-Edge)

37. Lateral Support

38. Knife-Edge Support

39. End Cap – Drive

40. End Cap - Idler

41. Motor Mount

42. Motor Plate

43. Spacers

44. Tie Bars

45. Table Top

46. Roller Shaft

47. Sidebar Deflection Analysis
Assumptions:
Height = 1.15”
Length (support to support) = 4.5”
Width (plastics) = .5”
Width (Aluminum) = .5”
Package weight = 12 Lb.
Elastic Moduli =
Aluminum - 57,000 ksi
UHMW PE ksi
Nylon 66 – 200 ksi
Polycarbonate – 392 ksi

48. Schematic Sidebar side view
Package weight
Support from below checkweigher
Support from below checkweigher

49. Sidebar Deflection Analysis
Iplastic = .063 in4
IAluminum = .048 in4
Max deflection at center of sidebar:
Aluminum ”
UHMW PE ”
Nylon ”
Polycarbonate ”
Worst Case Scenario

50. Sidebar Deflection Analysis Standard loading
Assume 2 equally loaded sidebars
Deflections:
UHMW PE ”
Nylon ”
Polycarbonate ”
Aluminum ”
Machining precision is .0005”, greater than potential deflection of Polycarbonate.

51. Raw Data – Tube (Slow Speed)

52. Raw Data – Tube (Fast Speed)

53. Raw Data – Box (Slow Speed)

54. Raw Data – Canister (Slow Speed)

55. Raw Data – Canister (Fast Speed)

56. Suggested Improvements
Introduce helicoils for easier threading
Hole in Motor Mount to allow access to screw covered by Motor Mount
Screws through Knife-edge end caps into knife-edge lateral support
Consider replacing more aluminum parts with polymer

57. Material Cost Material Vendor Height (in.) Width (in.) FDA-Approved?
Cost per ft.
Aluminum (anodized)
McMaster-Carr
1.5
0.375 no
$9.07
Aluminum (non-anodized)
1.25
$4.35
Metals Depot (MetalsDepot.com)
$2.75
Polycarbonate
0.5
$3.23
San Diego Plastics (
yes
$3.00
UHMW Polyethylene
$3.16
Modern Plastics (
$2.50
Nylon 66
$6.30