design & development of precision plastic gear transmissions · 1 © 2012 ticona gears webinar...
TRANSCRIPT
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1 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Design & Developmentof PrecisionPlastic Gear
Transmissions
David SheridanSenior Design EngineerTICONA
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2 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Overview
Methodical and rational procedure for designing and developing high-precision injection-molded plastic gear transmissions that function satisfactorily across the entire range of manufacturing tolerances and operating conditions.
Calculations to examine the effects of tolerances and environmental influences on gear geometry, operating center distance, and gear performance.
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3 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Outline
1. Why plastics for gears2. Gear types and arrangements for plastics3. Design and engineering4. Specifications5. Prototype parts and mold development6. Measurement and inspection7. Testing and validation8. Production molding
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4 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Plastic vs. Metal Gears
Lower cost– Injection molding vs. machining
• Especially for large quantities– As-molded, no finishing
Greater design flexibility– Parts consolidation– Molded-in features– Allow other gear geometries
• Easy to mold, difficult to machine, e.g., internal and cluster gears
Less noise–Lower modulus
• Do not transmit sound• Greater tooth deflection
increases load sharing and reduces transmission error effects
–Light weight, low inertia • Reduce dynamic loading
and noise
Plastic Advantages
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5 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Plastic vs. Metal Gears
Inherent lubricity– Do not need lubrication in
many low-load applications– Internal lubricants
• For applications that cannot use external lubricants
– Computer printers– Motorized toys
Chemical and corrosion resistance– External lubricants
• Grease• Oil
– Water• Lawn sprinklers• Water meters• Shower heads
Plastic Advantages
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6 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Outline
1. Why plastics for gears2. Gear types and arrangements for plastics3. Design and engineering4. Specifications5. Prototype parts and mold development6. Measurement and inspection7. Testing and validation8. Production molding
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7 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Base Circle
Involute Curve
Taut String
Involute Gearing
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8 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Involute Gearing
Advantages of Involute Gear Teeth Provide constant angular velocity (or ratio)
between two gears– “conjugate action”
Conjugate action is independent of changes in center distance (CD)– design flexibility– insensitive to manufacturing tolerances,
material expansion and contraction Manufacturing ease and accuracy with basic rack
Conjugate Action Independent of CD
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9 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Gear Types and Arrangements
Parallel Axis– Spur– Helical– External or Internal
Non-Parallel– Intersecting Axis
• Bevel, On-Center• Face, On-Center
– Non-Intersecting Axis• Worms• Bevel, Off-Center• Face, Off-Center
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10 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Straight Bevel Gears
Dudley
Critical on Mounting and Alignment
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Dudley
Not critical on center distance
Not critical on axial position
Recommended for Plastics
Face Gears
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12 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Worm Gearing
Characteristics High ratio Low part count Low cost Low noise Low capacity
Types of Worm Gears Involute worm (crossed-helical) Worm thread profile straight in
axial plane Worm thread profile straight in
normal plane Worm produced by conical mill or
grinding wheel with straight sides
These are NOT interchangeable!
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13 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Worm Gearing
Dudley
Critical on Mounting and Alignment
Semi-enveloping
Single-enveloping
Double-enveloping Cylindrical
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14 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Crossed-Helical Involute Gears
Not critical on center distance Not critical on axial position Theoretical POINT contact Useful for
– low power– low cost– low noise
Recommended for Plastic Worm Gearing
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15 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Gear Types and Arrangements
Parallel Axis– Spur– Helical– External
or Internal
Non-Parallel– Intersecting Axis
• Bevel, On-Center• Face, On-Center
– Non-Intersecting Axis• Worms• Bevel, Off-Center• Face, Off-Center
Epicyclics
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16 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Input Output
Epicyclic Drives
Epicyclic Arrangements Simple epicyclics Multi-stage epicyclics Compound epicyclics Coupled epicyclics Fixed differentials
Simple Epicyclics Planetary Star Sun
Characteristics Large reductions High power density Small space Split power path
Simple Planetary
Dudley
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17 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Single Reduction100%(∑ f·d2)
Double ReductionSingle Branch40%
Double ReductionDouble Branch25%
2-StagePlanetary9.5%
Relative Gear Train Size15:1 Reduction
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18 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Outline
1. Why plastics for gears2. Gear types and arrangements for plastics3. Design and engineering4. Specifications5. Prototype parts and mold development6. Measurement and inspection7. Testing and validation8. Production molding
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19 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Low Noise GearsLow Noise Gears Large Noise Gears
58.3dB
56.8dB61.1dB
68.5dB
Gear NoiseInfluence of Gear Quality
Low Noise Gears High Noise Gears
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20 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
The Plastic Gear Development Team
Molder
MaterialSupplier
Plastics Engineer
Quality ControlEngineer
ManufacturingEngineer
Gear Engineer
Project Engineer
Purchasing
ToolBuilder
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21 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Plastic Gear Development
Prime mover – Torque and speed– Inertia, natural freq.
Load(s)– Torque and speed– Special conditions– Inertia, natural freq.
Duty cycle Life Physical limits
Ratio Precision Efficiency Lubrication Environment
– Temperature– Chemical exposure– Moisture exposure
Test requirements Other
Identify Application – Voice of the Customer (VOC) Define Operating Requirements
Anticipate Future Applications
© 2011 Ticona Gears Webinar Gears-007r1 EN 12/11
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22 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Select Overall Transmission Geometry From requirements
– Minimum weight?– Minimum size?– Good plastic designs may use more
gears with split power path Carefully consider added features
– Runout– Distortion
Shafting and bearings– Precision– Efficiency
Housing considerations– Stiffness– Tolerances
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23 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Preliminary Gear Sizing
Select materials
Select preliminary gear geometry– Number of teeth– Size (pitch or module)– Profile (tooth proportions)
Nominal ambient conditions
Simple load analysis– K-factor– Unit load
For more information see ANSI/AGMA 1106-A97, Tooth Proportions for Plastic Gears
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Select Materials
Suit operating environment– Temperature range
• Dimensional behavior• Property behavior
– Chemical environment• Dimensional behavior• Property behavior
Appropriate property mix– Fatigue– Stiffness– Impact– Creep
For more information see AGMA 920-A01, Materials for Plastic Gears
Interaction with other components– Friction– Wear
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25 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Determine Production Tolerances
Gears– Diameters and tolerances– Tooth thickness and tolerance– Tip radius and tolerance– Accuracy grade
Housing– Center distance and tolerance
Shafts, bearings, and bushings– Diameters and tolerances– Runout
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26 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf© 2011 Ticona Gears Webinar Gears-007r1 EN 12/11
Precision Engineering Components
Dimensional Requirements (i.e., Tolerances)
MUST Equal Manufacturing Capabilities
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Preliminary Cost Estimate
Overall geometry Components sized Materials selected Tolerances
Cost Estimate
Alternative concepts
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Decision Point
Evaluate changes Refine cost estimate Commit tooling
Gear Design Begins Engineering data for materials Analyze “theoretical” gear tooth geometry
– Extreme geometry conditions– Extreme load conditions
Iterate
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Plastic Properties & Dimensions
Mechanical properties vary– Temperature– Moisture
Obtain strength & modulus data for load analysis– At operating conditions
Dimensions vary– Temperature
• Thermal expansion > metals (x10)
– Moisture
Obtain material data for dimensional stability considerations– Thermal expansion– Moisture expansion
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About Gear Tooth Geometry and Assembly
Always perfect in analytical models Always perfect in CAD models Always imperfect in production Operating environment alters geometry
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31 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf© 2011 Ticona Gears Webinar Gears-007r1 EN 12/11
Gear Engineer’s Job
To develop gear tooth geometry and assembly specifications that will produce gears that function satisfactorily under all operating conditions and across the entire range of manufacturing tolerances and environmental influences on dimensions.
© 2011 Ticona Gears Webinar Gears-007r1 EN 12/11
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One Approach
Use analytical models for gear tooth geometry and load analysis
Include all possible tolerances and environmental influences on dimensions in “effective” operating center distance
Design “Perfect” gear geometries– Develop gear geometry at tight
mesh– Re-analyze at open mesh– Analyze worst load condition
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Develop at Tight Mesh Condition
Maximum Material Condition
Maximum tooth thickness Minimum tip radius External gear
– Maximum outer diameter– Maximum root diameter
Internal gear– Minimum inner diameter– Minimum root diameter
Select Tight Center Distance
External gear set– Minimum effective
operating center distance
Internal gear set– Maximum effective
operating center distance
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Develop at Tight Mesh Condition
Optimize geometry– Maximize contact ratio– Minimize root clearance
• Tip interference?
– Minimize backlash– Minimize specific sliding
Load analysis at temperature– Minimize or balance stresses– Excessive tooth deflection?– Tip relief?
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Determine Effective OperatingCenter Distance RangeAssembled center distance range Mounting center distance and
tolerance Bushings, bearings, and shafts
– Maximum and minimum radial play– Runout
Gears– Total composite tolerances (Accuracy
grades)
Environmental effects Environmental conditions
– Temperature range– Moisture exposure
Dimensional response between housing and gears
– Thermal response (CLTE)– Moisture response
Examine when– Cold-Dry– Cold-Wet– Hot-Dry– Hot-Wet
Determine extreme CD range and conditions
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Assembled Center Distance RangeMounting Center Distance
CM
CMmin
CMmax
Housing– Center distance and tolerance
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Shafts, bushings, bearings– Diameters and tolerance
• Maximum and minimum radial play
Maximum radial play Minimum radial play
Maximum bushing diameter Minimum shaft diameter
Minimum bushing diameter Maximum shaft diameter
Assembled Center Distance RangeMounting Center Distance
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38 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Shafts, bushings, bearings– Concentricity or runout
Nominal Radius
Runout
Assembled Center Distance RangeMounting Center Distance
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39 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Gears– Accuracy grade
• Total composite tolerance (TCT)
Total Composite Error, TCE
Assembled Center Distance RangeMounting Center Distance
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)/2BRP(BRP)/2BRO(BROCC
GminPmin
GPMminAmin
GPGmaxPmax
GPMmaxAmax
TCTTCT)/2BRP(BRP)/2BRO(BROCC
Assembled Center Distance RangeExternal Gear Set
tolerance composite Totalplay radial Bearing
runout Bearingdistance center Mounting
distance center Assembled
TCTBRPBRO
CC
M
ASubscripts:
A - assembledM - mountingP - pinionG - gear
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)TCT(TCT)/2BRP(BRP)/2BRO(BROCC
GPGmaxPmax
GPMminAmin
)/2BRP(BRP)/2BRO(BROCC
GminPmin
GPMmaxAmax
Assembled Center Distance RangeInternal Gear Set
tolerance composite Totalplay radial Bearing
runout Bearingdistance center Mounting
distance center Assembled
TCTBRPBRO
CC
M
ASubscripts:
A - assembledM - mountingP - pinionG - gear
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42 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Add change in center distance due to temperature and moisture effects to assembled center distance range
Examine at temperature and moisture extremes– Cold-dry– Cold-wet– Hot-dry– Hot-wet
Find overall maximum and minimum operating center distance
CCC
CCC
AO
AO
maxmax
minmin
Operating Center Distance RangeEnvironmental Effects
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43 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
RHTTd
RHTTdC
PMPPMMP
GMGGMMG
)(2
)(2
Operating Center Distance RangeEnvironmental Effects- External gear set
expansion moisture of tCoefficien expansion thermal of tCoefficien
diameter pitch Operatinghumidity relative in Change
etemperatur in ChangeTdistance center in Change C
d
RH
A
AGG
APP
AMM
RHRHRHTTTTTTTTT
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44 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Operating Center Distance RangeEnvironmental Effects- Internal gear set
expansion moisture of tCoefficien expansion thermal of tCoefficien
diameter pitch Operatinghumidity relative in Change
etemperatur in ChangeTdistance center in Change C
d
RH
A
AGG
APP
AMM
RHRHRHTTTTTTTTT
RHTTd
RHTTdC
PMPPMMP
GMGGMMG
)(2
)(2
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45 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Analyze at Open Mesh Condition
Minimum Material Condition
Minimum tooth thickness Maximum tip radius External gear
– Minimum outer diameter– Minimum root diameter
Internal gear– Maximum inner diameter– Maximum root diameter
Open Center Distance
External gear set Maximum effective
operating center distance Internal gear set
– Minimum effective operating center distance
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46 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Check geometry– Contact ratio > 1?– If not, go back to beginning,
• Select new diametral pitchor module
• Change tooth proportions• Renegotiate tolerances
Load analysis at temperature– Load capacity– Excessive tooth deflection?– Tip relief?
Analyze at Open Mesh Condition
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47 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Analyze Other Load Conditions
Tight mesh condition is often hot and moist
Open mesh condition is often cold and dry
But worst load condition– Open mesh - minimum load
sharing– Hot and moist - minimum
material properties Transient conditions
– Cold housing and hot gears– Hot housing and cold gears
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48 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Finally
Iterate until all of the above works– Design time cheap– Changes during/after development costly ($ and )
Computer programs are necessary– Analytical programs preferred– Graphical programs often
cause problems
Write specifications
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49 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Outline
1. Why plastics for gears2. Gear types and arrangements for plastics3. Design and engineering4. Specifications5. Prototype parts and mold development6. Measurement and inspection7. Testing and validation8. Production molding
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50 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Specifications
Plastic gear transmissions require significant engineering effort. Components
– Gears– Housings– Shafts– Bearings
Variations– Manufacturing tolerances– Operating conditions
(i.e., temperature, moisture)• Dimensions• Material properties
Making certain the resulting design intent is specified clearly, accurately, and precisely to the gear manufacturer is essential to ensuring performance, cost, and delivery requirements are met.
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51 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Specifications
For more information see AGMA 909-A06, Specifications for Molded Plastic Gears
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52 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Specifications
For more information see AGMA 909-A06, Specifications for Molded Plastic Gears
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53 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Outline
1. Why plastics for gears2. Gear types and arrangements for plastics3. Design and engineering4. Specifications5. Prototype parts and mold development6. Measurement and inspection7. Testing and validation8. Production molding
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54 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf© 2011 Ticona Gears Webinar Gears-007r1 EN 12/11
High-Precision Gear Molding
Accurately predicting and consistently controlling (precision) shrinkage.
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55 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
The Controlling Principle
Shrinkage is only affected by material’s:– Orientation (polymer and reinforcement)– Temperature– Pressure
Almost everything can have an effect on at least one of these three things and will effect shrinkage.
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56 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Accuracy vs. PrecisionThe Target Analogy
High Accuracy Low Precision
High Precision Low Accuracy
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57 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Precision
Material– Crystalline resins vs.
amorphous resins– Shrinkage data– Fiber reinforcement– Viscosity
Part Geometry– Wall thicknesses– Features/ribs/holes/cams/etc.– Fillets inside corners– Gate(s)
Mold– Tolerances– Cavitation– Cooling
Process– Temperatures– Pressures– Cycle time
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58 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
m = 1.0 mm; z = 28; = 20 °; b = 15 mm; Hostaform C 27021
Web CenteredWeb Off-Center
PrecisionGeometry
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59 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
m = 1.0 mm; z = 28; = 20 °; b = 15 mm; Hostaform C 27021
6 Ribs 12 Ribs No Ribs
PrecisionRibs
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60 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
PrecisionGates
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61 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Filling Roundness
PrecisionGates
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62 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
FillingRoundness
PrecisionGates
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63 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
PrecisionMold Cooling
Bad Better
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64 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Best
PrecisionMold Cooling
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65 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Prototyping Verification of part and material performance Verification of manufacturing capabilities with dimensional
control Represent production as mush as possible
– Mold• Mold material• # cavities, runners, gates, etc.• Cooling channels
– Molder– Molding machine
• Barrel size– residence time
• Injection rate• Clamp tonnage
– Molding conditions• Temperatures
– Mold– Melt
• Cycle profile– Injection speed– Hold time & pressure– Cooling time
• Screw RPM & back pressure
Identical to Production
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66 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Prototype Mold DevelopmentPrecision
Follow material supplier’s molding recommendations Establish appropriate processing window
– Maximize material properties• Resist “correcting” dimensions with extreme
processing conditions– Wide, stable processing window
• Minimal variational effects on properties and dimensions– Maximize dimensional stability
• Consistent as-molded dimensions– Precision vs. cycle time
• Minimize post-molding shrinkage– Mold temperature must exceed operating temperature
• Pay now, or pay later! Design of experiments (DOE)
Stability Equals Precision
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67 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Prototype Mold DevelopmentAccuracy
Then correct tooling for shrinkage– Cut molds “steel safe”
• Undersized cavities• Oversized cores
– Use inserts Iterate Measure thoroughly
– Make what you designed
Then Correct for Accuracy
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68 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Outline
1. Why plastics for gears2. Gear types and arrangements for plastics3. Design and engineering4. Specifications5. Prototype parts and mold development6. Measurement and inspection7. Testing and validation8. Production molding
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69 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Plastic Gear Development Cycle
Design & Engineering
Prints & Specifications
Prototype Tool & Parts
Measurement & Inspection
Testing
Production
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70 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Inspection and Geometry Verification
During development Elemental inspection (CNC)
– Profile error (involute error)– Lead error (helix angle error)– Pitch error (spacing error)– Runout (radial position error)
General inspection– Outside radius– Root radius– Tooth thickness
• Measurement over pins or balls
Elemental Inspection for Development
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71 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Inspection and Geometry Verification
During production Composite inspection (Double-flank roll checker)
– Total composite error (TCE)– Tooth-to-tooth error (TTE)– Runout
Composite Inspection for QC
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72 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Outline
1. Why plastics for gears2. Gear types and arrangements for plastics3. Design and engineering4. Specifications5. Prototype parts and mold development6. Measurement and inspection7. Testing and validation8. Production molding
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73 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Testing and Validation
Geometry verification! Realistic
– Properly represents end-use conditions– Continuous testing when end-use is
intermittent• Overheating• No thermal or dimensional recovery
time• Temperature control
Effective– Static loads
• Creep and creep rupture– Impact loads
• Motor stall load• Motor rotor inertia load
Appropriate– Test procedures often developed for
metal gears
Keep It Real
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74 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Plastic Gear Development Cycle
Design & Engineering
Prints & Specifications
Prototype Tool & Parts
Measurement & Inspection
Testing
Production
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75 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Outline
1. Why plastics for gears2. Gear types and arrangements for plastics3. Design and engineering4. Specifications5. Prototype parts and mold development6. Measurement and inspection7. Testing and validation8. Production molding
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76 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Production
Utilize prototype knowledge– Minimize deviations
• Mold• Mold machine• Molding conditions
– Wide, stable process• Maximum material properties• Consistent dimensions
– Correct tooling for accuracyMeasure thoroughly
– Make what you designed and verified Run capability study Establish production QC methodology Produce!
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77 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf© 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Thank You
Questions?
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78 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
David SheridanSr. Design Engineer
Product Information800-833-4882
www.Ticona.com
© 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
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79 © 2012 Ticona Gears Webinar Gear_DesignPPT_AM_0212_016.pdf
Information is current as of February 2012 and is subject to change without notice.
The information contained in this publication should not be construed as a promise or guarantee of specific properties of our products.
Any determination of the suitability of a particular material and part design for any use contemplated by the user is the sole responsibility of the user. We strongly recommend that users seek and adhere to the manufacturer’s current instructions for handling each material they use.
Any existing intellectual property rights must be observed.
© 2012 Ticona. Except as otherwise noted, trademarks are owned by Ticona or its affiliates.
NOTICE TO USERS: