塑料产品与模具设计

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1、塑膠產品與模具設計PlasticPartandMoldDesign澆注系統設計FillingSystemDesign模具設計的優先順序PrioritiesofMoldDesign澆注系統設計(FillingSystemDesign)排氣系統設計(VentingSystemDesign)冷卻系統設計(CoolingSystemDesign)脫模系統設計(EjectingSystemDesign)澆注系統設計的優先順序PrioritiesofFillingSystemDesign產品設計(PartDesign

2、)型腔設計(CavityDesign)澆口設計(GateDesign)流道設計(RunnerDesign)豎澆道設計(SprueDesign)噴嘴設計(NozzleDesign)豎澆道Sprue主流道MainRunner成品Part澆口Gate冷料井ColdSlugWell支流道BranchRunner典型的澆注系統TypicalFillingSystem壁厚不均是注塑成形中最大的麻煩製造者。這對薄壁零件尤然。這些麻煩包括了遲滯現象、短射、凹陷、發赤、噴流、翹曲及長冷卻時間等；目前都可用CAE以直接或間接

3、的方式預測。Non-uniformwallthicknessisthebiggesttroublemakerinplasticinjectionmolding.Thisisespeciallytruetothin-wallpart.Thetroubles,includinghesitation,shortshot,sinkmark,blush,jetting,warpageandlongcoolingtimeetc.,canbepredicted,directlyorindirectly,byusingC

4、AE.壁厚不均Non-uniformWallThickness壁厚設計WallThicknessDesign差[Poor]較好[Better]最好[Best]掏空設計(1)CoringOutDesign(1)改進設計[Improved]原設計[Original]差[Poor]改進[Improved]掏空設計(2)CoringOutDesign(2)氣泡或/和凹陷的形成Voidor/andSinkMarkForming氣泡(Void)凹陷(SinkMark)肋厚和內圓角半徑的影響TheEffectofRib

5、Thickness&FilletRadius肋的底部厚度BottomThicknessofRibW0.5W2.5WW1.2WD1.5WD(A)(B)肋的設計(一)RibDesign(1)t=wallthichnessB=0.5tC=3tAAD=2BE=0.13mm(radius)F=1.5-2deg假如需要更大的強度,可增加肋的數目Ifmorestrengthisrequired,addadditionalribs.FBDECt肋的設計(二)RibDesign(2)肋的設計(三)RibDesign(3)與

6、側壁相連之凸轂(熱塑性塑膠)BossatWall(Thermoplastics)A=凸轂附著處壁厚wallthicknessB=凸轂外環直徑dia.ofbossoverradiiC=0.5AD=2BE=1~2degF=0.13mm(radius)G=DH=0.8AI=A/4J=2BK=0.3~1JL=0.5ALHA'A'KEIGJDAFCBSectionA'-A'遠離側壁之凸轂(熱塑性塑膠)BossAwayFromWall(Thermoplastics)A=凸轂附著處壁厚wallthicknessB=凸轂

7、外環直徑(含底部修整圓弧半徑)dia.ofbossoverradiiC=0.5AD=2BE=1-2degF=0.13mm(radius)G=0.95DH=0.3Gmin.toGmax.I=0.5AHEFDFGCBAI外側凸轂OutsideBossA'A'A(DIA)BB=AB=2A(max.)SectionA'-A'Where1/r:樑的曲率curvatureofthebeamM:彎曲力矩bendingmomentE:彈性模數modulusofelasticityI:斷面積對中立軸的慣性矩momentof

8、inertiaofthecross-sectionalareawithrespecttotheneutralaxisEI:撓曲剛性flexuralrigidity撓曲剛性FlexuralRigidityNeutralAxis?10.8平板和肋板的比較ComparisonbetweenPlain&RibbedPlates和平板比，若基於相同的慣性矩(剛性)，肋板需料少了43%，I/A卻增加了1.79倍。肋板的最大厚度減為平板的1