Checkweigher Checkweigher Design ConceptDesign Concept

All-Fill Inc. All-Fill Inc.

Dan MacGuigan, Matt Dan MacGuigan, Matt Griffith, Griffith,

Phil Mitchell, Richard MaurerPhil Mitchell, Richard Maurer

Introduction of ProjectIntroduction of Project

• Weighs Products

• Quality Control

• Rejects out-of-spec Products

•Up to 200 products/min.

Improvement Objectives Improvement Objectives (Wants)(Wants)

Decrease CostDecrease Cost MaterialMaterial Manufacturing/Manufacturing/

Machining TimeMachining Time Assembly TimeAssembly Time

Fewer PartsFewer Parts Fewer Required ToolsFewer Required Tools

Increase Increase MarketabilityMarketability Easier MaintenanceEasier Maintenance

““Tool-less” Belt Tool-less” Belt ChangesChanges

Drive BeltDrive Belt Conveyor BeltConveyor Belt

Faster Order Faster Order TurnaroundTurnaround

Design ConstraintsDesign Constraints

SafetySafety Protection From Moving PartsProtection From Moving Parts Design Against Catastrophic FailureDesign Against Catastrophic Failure

WeightWeight Cannot Increase Overall WeightCannot Increase Overall Weight

FootprintFootprint Cannot Change Current FootprintCannot Change Current Footprint

LifeLife Service Life Cannot DecreaseService Life Cannot Decrease

Improvement MetricsImprovement Metrics

MetricMetric CurrentCurrent TargetTarget AchievedAchieved

Material CostMaterial Cost $290/$74$290/$7400

$230/$59$230/$5900

$220/$18$220/$1844

Manufacturing TimeManufacturing Time 18.5 hrs18.5 hrs 14 hrs14 hrs 10 hrs10 hrs

Assembly TimeAssembly Time 17 min17 min 14 min14 min 14 min14 min

Number of PartsNumber of Parts 86/20886/208 75/10075/100 80/9980/99

# of Rollers# of Rollers 11 22 22

# of Tools Required# of Tools Required

for Belt Changefor Belt Change33 00 00

How to Meet WantsHow to Meet Wants

Divide Checkweigher into Divide Checkweigher into SubsystemsSubsystems

Each Subsystem Offers BenefitsEach Subsystem Offers Benefits Some Subsystems InterrelatedSome Subsystems Interrelated Compounded ImprovementsCompounded Improvements

Identification of Identification of SubsystemsSubsystems Motor MountMotor Mount

Roller AttachmentRoller Attachment Knife-EdgeKnife-Edge Sidebars & Tie Sidebars & Tie

BarsBarsCurrent Design

Motor MountMotor Mount WantsWants

Lower Cost (Benefits Sponsor)Lower Cost (Benefits Sponsor) Fewer Small Parts (Nuts, Fewer Small Parts (Nuts,

Washers, etc.)Washers, etc.) Less Costly ManufacturingLess Costly Manufacturing Faster AssemblyFaster Assembly

Increase Marketability (Benefits Increase Marketability (Benefits Customer)Customer)

Easy Tensioning of Timing BeltEasy Tensioning of Timing Belt ““Tool-less” / Fast Belt ChangeTool-less” / Fast Belt Change

MetricMetric CurreCurrentnt

TargTargetet

AchieveAchievedd

Time to Change BeltTime to Change Belt 7.3 7.3 minmin

5 5 minmin

3.3 min3.3 min

Time to Properly Time to Properly Tension beltTension belt

2 min2 min 1 1 minmin

0.5 min0.5 min

# of Tools to Change # of Tools to Change BeltBelt

33 00 00

Number of PartsNumber of Parts 66 55 44

Motor Mount - CurrentMotor Mount - Current

Motor Mount - NewMotor Mount - New

Thumb Screw

Roller IntegrationRoller Integration WantsWants

Lower Cost (Benefits Lower Cost (Benefits Sponsor)Sponsor)

Lower Manufacturing CostLower Manufacturing Cost Increased Marketability Increased Marketability

(Benefits Customer)(Benefits Customer) ““Tool-less” Belt ChangeTool-less” Belt Change More VersatileMore Versatile

MetricMetric CurreCurrentnt

TargTargetet

AchievAchieveded

Time to AssembleTime to Assemble 17 17 minmin

13 13 minmin

14 min14 min

# of Rollers Types# of Rollers Types 11 22 22

# of Tools to # of Tools to Change BeltChange Belt

33 00 00

Manufacturing CostManufacturing Cost $1110$1110 $840$840 $600$600

Roller Integration – Roller Integration – CurrentCurrent

Current Attachment Points of Rollers

Roller Attachment

Points

Roller Integration – NewRoller Integration – NewEnd CapsEnd Caps

Conventional Idler End Cap

Drive End Cap

Knife-Edge End Cap

End Cap IntegrationEnd Cap Integration

Concept Roller Attachment Points

Snap Ring and Pliers

Cotter Pin

Knife-EdgeKnife-Edge WantsWants

Lower Cost (Benefits Lower Cost (Benefits Sponsor)Sponsor)

Lower CostLower Cost SimplerSimpler

Increased Marketability Increased Marketability (Benefits Customer)(Benefits Customer)

Less VibrationLess Vibration Less Belt WearLess Belt Wear Shorter Transition DistanceShorter Transition Distance

MetricMetric CurreCurrentnt

TargTargetet

AchievAchieveded

Time to Time to ManufactureManufacture

7 hr7 hr 5 hr5 hr 3.7 hr3.7 hr

Material CostMaterial Cost $740$740 $590$590 $184$184

# of Parts # of Parts 208208 100100 9999

Knife-Edge - CurrentKnife-Edge - Current

ProblemsProblems Many Small PartsMany Small Parts ExpensiveExpensive Difficult to AssembleDifficult to Assemble

Bearing

Nylon Spacer

Knife-Edge - NewKnife-Edge - New

Material – PTFE (TeflonMaterial – PTFE (Teflon®®)) Low Coefficient of FrictionLow Coefficient of Friction High Melting TemperatureHigh Melting Temperature InexpensiveInexpensive

Few PartsFew Parts

Sidebars & Tie BarsSidebars & Tie Bars WantsWants

Lower Cost (Benefits Lower Cost (Benefits Sponsor)Sponsor)

Lower Material CostLower Material Cost Shorter Manufacturing TimeShorter Manufacturing Time

End Cap Integration End Cap Integration Increased Marketability Increased Marketability

(Benefits Customer)(Benefits Customer) FDA ApprovedFDA Approved LighterLighter

MetricMetric CurrentCurrent TargetTarget AchieveAchievedd

Material Cost Material Cost (per pair)(per pair)

$20$20 $10$10 $6$6

Mass/LengthMass/Length 0.05 0.05 lbm/inlbm/in

0.03 0.03 lbm/inlbm/in

0.03 0.03 lbm/inlbm/in

FDA ApprovedFDA Approved YesYes YesYes AvailablAvailablee

Sidebars - NewSidebars - New PolycarbonatePolycarbonate

LighterLighter Less ExpensiveLess Expensive Easily MachinedEasily Machined Sufficient Sufficient

Mechanical Mechanical PropertiesProperties

FDA Approved FDA Approved AvailableAvailable

End Cap IntegrationEnd Cap Integration

Tie Bars - NewTie Bars - New Redesigned for Redesigned for

Compatibility with Compatibility with Polycarbonate SidebarsPolycarbonate Sidebars Single Attachment to Single Attachment to

SidebarSidebar Material ChangeMaterial Change

From Aluminum to From Aluminum to PolycarbonatePolycarbonate

Less CostlyLess Costly LighterLighter

Assembled PrototypeAssembled Prototype

TestingTesting

WeightWeight Assembly TimeAssembly Time Maintenance TimeMaintenance Time

Drive Belt ChangeDrive Belt Change Conveyor Belt ChangeConveyor Belt Change

Accuracy & PrecisionAccuracy & Precision Product Weight Product Weight

Measurements Measurements

WeightWeight

Current WeightCurrent Weight 7lbs 4 ounces7lbs 4 ounces

New WeightNew Weight 6lbs 3ounces6lbs 3ounces

17.4% Weight 17.4% Weight ReductionReduction

Current

Prototype

Assembly TimeAssembly Time

Current AssemblyCurrent Assembly 17 Minutes17 Minutes 4 Tools Needed4 Tools Needed

New AssemblyNew Assembly 14 minutes14 minutes 2 Tools Needed2 Tools Needed

18% Reduction In Assembly Time

Assembly Time

0

2

4

6

8

10

12

14

16

18

Current Prototype

Design

Tim

e (m

in)

Current Prototype

Maintenance TimeMaintenance Time Conveyor Belt Change Time Conveyor Belt Change Time

IncreasedIncreased Due to Sidebar Material ChangeDue to Sidebar Material Change Introduce Helicoils in Next PrototypeIntroduce Helicoils in Next Prototype

Drive Belt Change Time Drive Belt Change Time DecreasedDecreased Old Time: 7:30Old Time: 7:30 New Time: 3:30New Time: 3:30 47% Decrease in Time Required47% Decrease in Time Required ““Tool-less” Tool-less” Less Hardware RequiredLess Hardware Required

Accuracy and Precision Accuracy and Precision TestingTesting

Sample Products Run on Actual MachineSample Products Run on Actual Machine Three Different ProductsThree Different Products Representative of a Range of WeightsRepresentative of a Range of Weights

Three Conveyor Units TestedThree Conveyor Units Tested Old DesignOld Design Conventional PrototypeConventional Prototype Knife-Edge PrototypeKnife-Edge Prototype

Accuracy ResultsAccuracy Results

46.5

47

47.5

48

48.5

49

Offline Mass

Old Design

Prototype

Knife Edge

Average Online Mass - Tube in Box

46.5

47

47.5

48

48.5

49

100 200

Conveyor Speed (fpm)

Ma

ss

(g

)

Average Online Mass - Canister

362

364

366

368

370

372

374

100 200

Conveyor Speed (fpm)

Ma

ss

(g

)Average Online Mass - Weight in Box

2200

2210

2220

2230

2240

2250

100

Conveyor Speed (fpm)

Ma

ss

(g

)

Offline Mass Compared to Data From:

•Old Design

•Prototype of New Design

• Prototype of New Design with Knife-edge

Precision ResultsPrecision Results At Least 1 New Design At Least 1 New Design

Outperformed Current Outperformed Current Checkweigher in Every TestCheckweigher in Every Test

Overall BenefitsOverall Benefits Tool-less Belt ChangeTool-less Belt Change

Motor MountMotor Mount Cotter PinCotter Pin

LighterLighter SidebarsSidebars Tie BarsTie Bars

Fewer PartsFewer Parts Knife-EdgeKnife-Edge Motor MountMotor Mount

VersatileVersatile End CapsEnd Caps Knife-EdgeKnife-Edge SidebarsSidebars

Less ExpensiveLess ExpensiveComponentComponent Money Money

SavedSaved

Motor MountMotor Mount $11$11

Knife-EdgeKnife-Edge $480$480

Sidebar (2)Sidebar (2) $14$14

Tie Bar (3)Tie Bar (3) $21$21

Manufacturing Manufacturing TimeTime

$510$510

TOTAL SAVED: $1036(60% of Current Checkweigher Cost) (~33% of

Retail)

ConclusionConclusion DesignDesign

Lighter Lighter More VersatileMore Versatile Easier MaintenanceEasier Maintenance Less ExpensiveLess Expensive

PrototypingPrototyping Fully Functional PrototypeFully Functional Prototype 100% Scale100% Scale

TestingTesting 18% Assembly Time 18% Assembly Time

ReductionReduction ““Tool-Less” Belt ChangesTool-Less” Belt Changes More AccurateMore Accurate More PreciseMore Precise

Implementation PlanImplementation Plan

Provide to All-Fill:Provide to All-Fill: Bill of MaterialsBill of Materials Complete Electronic Drawing PackageComplete Electronic Drawing Package Checkweigher PrototypesCheckweigher Prototypes

Manufacture Three Complete Manufacture Three Complete Improved Checkweigher Designs Improved Checkweigher Designs

Run Mock Production Line Run Mock Production Line

QuestionsQuestions

AcknowledgementsNate CloudHa DinhEd WhiteDave KendellSteve Beard

BoM - ConventionalBoM - Conventional

Conventional Roller

Quantity Part Drawing Number

1 Motor with Sprocket N/A

1 Motor Plate MM1

2 Spacer MM2

1 Motor Mount MM3

3 Tie Bar S1

2 Sidebar S2

2 Drive End Cap EC1

2 Idler End Cap EC2

1 Idler Roller with Bearings N/A

1Drive Roller with Bearings

and Sprocket N/A

2 Roller Shaft S3

1 Table Top S4

1 Drive Belt N/A

1 Conveyor Belt N/A

     

Quantity Hardware

6 1/4-20x1/2" Hex Socket Bolt

9 5-40x1/4" Flat Head Screw

2 1/4-20x1" Hex Socket Bolt

2 1/4-20 Washer

2 1/4-20 Lock Washer

4 1/4-20 Thumb Wheel

2 10-32x1" Hex Bolt

4 10-32 Washer

4 10-32 Lock Washer

2 10-32x1" Wing Bolt

2 10-32 Thumb Wheel

4 10-32x1/2" Hex Socket Bolt

4 Brass Washer (ID 3/8", OD .75")

4Hairpin Cotter Pin (Wire Diameter = 0.1")

8 1/8"x1" Steel Dowel

SidebarSidebar

Right End Cap (Knife-Right End Cap (Knife-Edge)Edge)

Left End Cap (Knife-Left End Cap (Knife-Edge)Edge)

Lateral SupportLateral Support

Knife-Edge SupportKnife-Edge Support

End Cap – DriveEnd Cap – Drive

End Cap - IdlerEnd Cap - Idler

Motor MountMotor Mount

Motor PlateMotor Plate

SpacersSpacers

Tie BarsTie Bars

Table TopTable Top

Roller ShaftRoller Shaft

Sidebar Sidebar Deflection Deflection AnalysisAnalysisAssumptions:Assumptions:

Height = 1.15”Height = 1.15”

Length (support to support) = 4.5”Length (support to support) = 4.5”

Width (plastics) = .5”Width (plastics) = .5”

Width (Aluminum) = .5”Width (Aluminum) = .5”

Package weight = 12 Lb.Package weight = 12 Lb.

Elastic Moduli =Elastic Moduli =

Aluminum - 57,000 ksiAluminum - 57,000 ksi

UHMW PE - 100 ksiUHMW PE - 100 ksi

Nylon 66 – 200 ksiNylon 66 – 200 ksi

Polycarbonate – 392 ksiPolycarbonate – 392 ksi

SchematicSchematicSidebar side viewSidebar side view

Package weight

Support from below checkweigher

Support from below checkweigher

Sidebar Deflection Sidebar Deflection AnalysisAnalysis

IIplastic plastic = .063 in= .063 in44

IIAluminum Aluminum = .048 in= .048 in44

Max deflection at center of sidebar:Max deflection at center of sidebar: Aluminum - Aluminum - .0000084”.0000084” UHMW PE - UHMW PE - .0036”.0036” Nylon 66 - Nylon 66 - .0018”.0018” Polycarbonate - Polycarbonate - .00092”.00092”

Worst Case Scenario

Sidebar Deflection AnalysisSidebar Deflection AnalysisStandard loadingStandard loading

Assume 2 equally loaded sidebarsAssume 2 equally loaded sidebars Deflections:Deflections:

UHMW PE UHMW PE .0018”.0018” Nylon 66Nylon 66 .0009”.0009” PolycarbonatePolycarbonate .00046”.00046” AluminumAluminum .0000042” .0000042”

Machining precision is .0005”, Machining precision is .0005”, greater than potential deflection of greater than potential deflection of Polycarbonate.Polycarbonate.

Raw Data – Tube (Slow Raw Data – Tube (Slow Speed)Speed)

Scatter in Data

46.547.047.548.048.549.049.550.0

0 10 20 30

Trial

Mas

s (g

) Conv. Prototype

Old Design

Knife Edge

Offline Mass

Raw Data – Tube (Fast Raw Data – Tube (Fast Speed)Speed)

Scatter in Data

44.045.046.047.048.0

49.050.051.052.0

0 5 10 15 20 25 30

Trial

Ma

ss

(g

) Conv. Prototype

Old Design

Knife Edge

Off Line Mass

Raw Data – Box (Slow Raw Data – Box (Slow Speed)Speed)

Scatter in Data

2180.0

2200.0

2220.0

2240.0

2260.0

2280.0

2300.0

0 5 10 15 20 25 30

Trial

Ma

ss

(g

) Conv. Prototype

Old Design

Knife Edge

Off Line Mass

Raw Data – Canister (Slow Raw Data – Canister (Slow Speed)Speed)Scatter in Data

366.0

367.0

368.0

369.0

370.0

371.0

372.0

373.0

0 5 10 15 20 25 30

Trial

Ma

ss

(g

) Conv. Prototype

Old Design

Knife Edge

Off Line Mass

Raw Data – Canister Raw Data – Canister (Fast Speed)(Fast Speed)

Scatter in Data

360.0362.0364.0366.0368.0370.0372.0374.0376.0378.0380.0382.0

0 5 10 15 20 25 30

Trial

Mas

s (g

) Conv. Prototype

Old Design

Kinfe Edge

Off Line Mass

Suggested ImprovementsSuggested Improvements

Introduce helicoils for easier Introduce helicoils for easier threadingthreading

Hole in Motor Mount to allow access Hole in Motor Mount to allow access to screw covered by Motor Mountto screw covered by Motor Mount

Screws through Knife-edge end caps Screws through Knife-edge end caps into knife-edge lateral supportinto knife-edge lateral support

Consider replacing more aluminum Consider replacing more aluminum parts with polymerparts with polymer

Material CostMaterial 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) McMaster-Carr 1.25 0.375 no $4.35

Aluminum (non-anodized) Metals Depot (MetalsDepot.com) 1.25 0.375 no $2.75

Polycarbonate McMaster-Carr 1.5 0.5 no $3.23

Polycarbonate San Diego Plastics (www.sdplastics.com) 1.5 0.5 yes $3.00

UHMW Polyethylene McMaster-Carr 1.5 0.5 yes $3.16

UHMW Polyethylene Modern Plastics (www.modernplastics.com) 1.5 0.5 yes $2.50

Nylon 66 McMaster-Carr 1.5 0.5 yes $6.30