外文翻译--自适应系统温度调节的电动注塑模具 英文版.pdf

JournalofMaterialsProcessingTechnology187188(2007)690693AdaptivesystemforelectricallydriventhermoregulationofmouldsforinjectionB.Nardina,B.Zagara,ASlovenia,Abstractditionsmeans.mouldit.wpatent.on-lineinfluencecontrol.2006ElsevierB.V.Allrightsreserved.Ksimulations1.Developmentoftechnologyofcoolingmouldsviathermo-electrical(TEM)meansderivesoutoftheindustrialpraxisandproblems,i.e.atdesign,toolmakingandexploitationoftools.Currentcoolingtechnologieshavetechnologicallimitations.Theirfinitepletelyretrollableingtechnologies.eningonlytionand1.1.prPlasticprocessingisbasedonheattransferbetweenplasticmaterialandmouldcavity.Withincalculationofheattransferoneshouldconsidertwomajorfacts:firstisallusedenergy0924-0136/$doi:limitationscanbelocatedandpredictedinadvancewithelementanalyses(FEA)simulationpackagesbutnotcom-avoided.Resultsofadiversestateoftheartanalysesvealedthatallexistingcoolingsystemsdonotprovidecon-heattransfercapabilitiesadequatetofitintodemand-technologicalwindowsofcurrentpolymerprocessingPolymerprocessingisnowadayslimited(intermofshort-theproductioncycletimeandwithinthatreducingcosts)withheatcapacitymanipulationcapabilities.Otherproduc-optimizationcapabilitiesarealreadydriventomechanicalpolymerprocessinglimitations3.Correspondingauthors.Tel.:+3863490920；fax:+38634264612.E-mailaddress:Blaz.Nardintecos.si(B.Nardin).whichisbasedonfirstlawofthermodynamicslawofenergyconservation1,secondisvelocityofheattransfer.Basictaskatheattransferanalysesistemperaturecalculationovertimeanditsdistributioninsidestudiedsystem.Thatlastdependsonvelocityofheattransferbetweenthesystemandsurroundingsandvelocityofheattransferinsidethesystem.Heattransfercanbebasedasheatconduction,convectionandradiation1.1.2.CoolingtimeCompleteinjectionmouldingprocesscyclecomprisesofmouldclosingphase,injectionofmeltintocavity,packingpres-surephaseforcompensatingshrinkageeffect,coolingphase,mouldopeningphaseandpartejectionphase.Inmostcases,thelongesttimeofallphasesdescribedaboveiscoolingtime.Coolingtimeininjectionmouldingprocessisdefinedastimeneededtocooldowntheplasticpartdowntoejectiontemperature1.seefrontmatter2006ElsevierB.V.Allrightsreserved.10.1016/j.jmatprotec.2006.11.052aTECOS,ToolandDieDevelopmentCentreofbFacultyofElectricalEngineeringOneofthebasicproblemsinthedevelopmentandproductionprocessinthemould.PrecisestudyofthermodynamicprocessesinmouldsSuchsystemupgradesconventionalcoolingsystemswithintheInthepaper,theauthorswillpresentresultsoftheresearchproject,whichThetestingstage,theprototypestageandtheindustrializationphasethermoregulationofthemouldoverthecycletimeandoverallPresentedapplicationcanpresentamilestoneinthefieldofmouldtemperatureeywords:Injectionmoulding；Mouldcooling；Thermoelectricmodules；FEMIntroduction,definitionofproblemmoulding.Glojeka,D.KrizajbKidricevaCesta25,3000Celje,Slovenia,Ljubljana,Sloveniaofmouldsforinjectionmouldingisthecontroloftemperaturecon-showed,thatheatexchangecanbemanipulatedbythermoelectricalorcanbeastandaloneapplicationforheatmanipulationwithinascarriedoutinthreephasesanditsresultsarepatentedinA6862006willbepresented.Themainresultsoftheprojectweretotalandrapidonqualityofplasticproductwithemphasisondeformationandproductqualitycontrolduringtheinjectionmouldingprocess.ThermalprocessesininjectionmouldingplasticocessingB.Nardinetal./JournalofMaterialsProcessingTechnology187188(2007)690693691coolingfrommouldandtemperaturefrom2.entmosti.e.lines),accumulatedtoityintoalterlikintetheerties.withatureindependentdonefromsimulation.TEM2.1.wtricalTheFig.2.TEMblockdiagram.nowneverusedintheinjectionmouldingapplications.TEMmodule(seeFig.2)isadevicecomposedofproperlyarrangedpairsofPandNtypesemiconductorsthatarepositionedbetweentwoceramicplatesformingthehotandthecoldthermoelectriccoolersites.Pounit.transferallosystem.modulesperatureheatconstanttricwithtemchannelscontrollablemouldFig.1.Mouldtemperaturevariationacrossonecycle2.Themainaimofacoolingprocessistoloweradditionaltimewhichistheoreticallyneedless；inpraxis,itextends45upto67%ofthewholecycletime1,4.Fromliteratureandexperiments1,4,itcanbeseen,thatthetemperaturehasenormousinfluenceontheejectiontimethereforethecoolingtime(costs).InjectionmouldingprocessisacyclicprocesswheremouldvariesasshowninFig.1wheretemperaturevariesaveragevaluethroughwholecycletime.CoolingtechnologyforplasticinjectionmouldsAsitwasalreadydescribed,therearealreadyseveraldiffer-technologies,enablingtheuserstocoolthemoulds5.Theconventionalisthemethodwiththedrillingtechnology,producingholesinthemould.Throughtheseholes(coolingthecoolingmediaisflowing,removingthegeneratedandheatfromthemould1,2.Itisalsoveryconvenientbuildindifferentmaterials,withdifferentthermalconductiv-withtheaimtoenhancecontrolovertemperatureconditionsthemould.Suchapproachesaresocalledpassiveapproacheswardsthemouldtemperaturecontrol.Thechallengingtaskistomakeanactivesystem,whichcanthethermalconditions,regardingtothedesiredaspects,eproductqualityorcyclestime.Oneofsuchapproachesisgratingthermalelectricalmodules(TEM),whichcanalterthermalconditionsinthemould,regardingthedesiredprop-Withsuchapproach,theonecancontroltheheattransferthetimeandspacevariable,whatmeans,thatthetemper-canberegulatedthroughouttheinjectionmouldingcycle,ofthepositioninthemould.Theheatcontrolisbythecontrolunit,wheretheinputvariablesarereceivedthemanualinputortheinputfromtheinjectionmouldingWiththeoutputvalues,thecontrolunitmonitorsthemodulebehaviour.Thermoelectricmodules(TEM)Fortheneedsofthethermalmanipulation,theTEMmoduleasintegratedintomould.Interactionbetweentheheatandelec-variablesforheatexchangeisbasedonthePeltiereffect.phenomenonofPeltiereffectiswellknown,butitwasuntilthemagnitudeandthepolarityofthesuppliedelectricApplicationformouldcoolingThemainideaoftheapplicationisinsertingTEMmodulewallsofthemouldcavityservingasaprimaryheattransferSuchbasicassemblycanbeseeninFig.3.SecondaryheatisrealizedviaconventionalfluidcoolingsystemthatwsheatflowsinandoutfrommouldcavitythermodynamicDevicepresentedinFig.3comprisesofthermoelectric(A)thatenableprimarilyheattransferfromortotem-controllablesurfaceofmouldcavity(B).Secondarytransferisenabledviacoolingchannels(C)thatdelivertemperatureconditionsinsidethemould.Thermoelec-modules(A)operateasheatpumpandassuchmanipulateheatderivedtoorfromthemouldbyfluidcoolingsys-(C).Systemforsecondaryheatmanipulationwithcoolingworkasheatexchanger.Toreduceheatcapacityofareathermalinsulation(D)isinstalledbetweenthecavity(F)andthemouldstructureplates(E).Fig.3.StructureofTEMcoolingassembly.692B.Nardinetal./JournalofMaterialsProcessingTechnology187188(2007)690693aturesystem.inputandinformationcutionrelations.ormediacurrentofofFurthermore,filesDescribedresearchtroltheoretical,aspectoneinto3.mouldingdesigndays(Moldfloespeciallydesignerstionunreliabletion.TEM,bandsimulationsFig.5.Cross-sectionofaprototypeinFEMenvironment.3.1.Physicalmodel,FEManalysisImplementationofFEManalysesintodevelopmentprojectwasdoneduetoauthorslongexperienceswithsuchpackages4andpossibilitytoperformdifferenttestinthevirtualenvi-ronment.eninthemdeCOMSOLidenticalpossibletakingfluidphysicswimpactgoaling.temperatureFig.4.Structurefortemperaturedetectionandregulation.ThewholeapplicationconsistsofTEMmodules,atemper-sensorandanelectronicunitthatcontrolsthecompleteThesystemisdescribedinFig.4andcomprisesofanunit(inputinterface)andasupplyunit(unitforelectronicpowerelectronicsupplyHbridgeunit).Theinputandsupplyunitswiththetemperaturesensorloopareattachedtoacontrolunitthatactsasanexe-unittryingtoimposepredefinedtemperate/time/positionUsingthePeltiereffect,theunitcanbeusedforheatingcoolingpurposes.ThesecondaryheatremovalisrealizedviafluidcoolingseenasheatexchangerinFig.4.Thatunitisbasedoncoolingtechnologiesandservesasasinkorasourceaheat.Thisenablescompletecontrolofprocessesintermstemperature,timeandpositionthroughthewholecycle.itallowsvarioustemperature/time/positionpro-withinthecyclealsoforstartingandendingprocedures.technologycanbeusedforvariousindustrialandpurposeswhereprecisetemperature/time/positioncon-isrequired.ThepresentedsystemsinFigs.3and4wereanalysedfromtheaswellasthepracticalpointofview.ThetheoreticalwasanalysedbytheFEMsimulations,whilethepracticalbythedevelopmentandtheimplementationoftheprototyperealapplicationtesting.FEManalysisofmouldcoolingCurrentdevelopmentofdesigningmouldsforinjectioncomprisesofseveralphases3.Amongthemisalsoandoptimizationofacoolingsystem.Thisisnowa-performedbysimulationsusingcustomizedFEMpackagesw4)thatcanpredictcoolingsystemcapabilitiesanditsinfluenceonplastic.Withsuchsimulations,mouldgatherinformationonproductrheologyanddeforma-duetoshrinkageasellasproductiontimecycleinformation.Thisthermalinformationisusuallyaccuratebutcanstillbeincasesofinsufficientrheologicalmaterialinforma-Forthehighqualityinputforthethermalregulationofitisneededtogetapictureaboutthetemperaturedistri-utionduringthecycletimeandthroughoutthemouldsurfacethroughoutthemouldthickness.Therefore,differentprocessareneeded.WholeprototypecoolingsystemwasdesignedinFEMvironment(seeFig.5)throughwhichtemperaturedistributioneachpartofprototypecoolingsystemandcontactsbetweenwereexplored.Forsimulatingphysicalpropertiesinsideavelopedprototype,asimulationmodelwasconstructedusingMultiphysicssoftware.ResultwasaFEMmodeltorealprototype(seeFig.7)throughwhichitwastocompareandevaluateresults.FEMmodelwasexploredintermofheattransferphysicsintoaccounttwoheatsources:awaterexchangerwithphysicsandathermoelectricmodulewithheattransfer(onlyconductionandconvectionwasanalysed,radiationasignoredduetolowrelativetemperatureandthereforelowontemperature).BoundaryconditionsforFEManalysesweresetwiththetoachieveidenticalworkingconditionsasinrealtest-Surroundingairandthewaterexchangerweresetatstableof20C.Fig.6.TemperaturedistributionaccordingtoFEManalysis.B.Nardinetal./JournalofMaterialsProcessingTechnology187188(2007)690693693atureFig.inresponsevtemperaturewhatproblemsmounting,intelligent3.2.testedtionscontrolmouldwlatedsimulatingmouldingsors,temperaturerepresentsmoulding4.nectionmilestoneincoolingapplications.Itsintroductionintomouldsforinjectionmouldingwithitsproblematiccoolingconstructionandproblematicprocessingofpreciseandhighqualityplasticpartsrepresentshighexpectations.TheauthorswereassumingthattheuseofthePeltiereffectcanbeusedforthetemperaturecontrolinmouldsforinjectionmoulding.Withtheapproachbasedonthesimulationworkandtherealproductionoflaboratoryequipmentproved,theassump-tionswereconfirmed.SimulationresultsshowedawideareaofpossibleapplicationofTEMmoduleintheinjectionmouldingprocess.Withmentionedfunctionalityofatemperatureprofileacrosscycletime,injectionmouldingprocesscanbefullycontrolled.Industrialproblems,suchasuniformcoolingofproblematicAancesolvmore,ofrefloityofproduct).icantlyTheofcontroloferances.mouldingandRefer123Fig.7.Prototypeinrealenvironment.ResultsoftheFEManalysiscanbeseeninFig.6,i.e.temper-distributionthroughthesimulationareashowninFig.5.6representssteadystateanalysiswhichwasveryaccuratecomparisontoprototypetests.Inordertosimulatethetimealsothetransientsimulationwasperformed,showingerypositiveresultsforfuturework.Itwaspossibletoachieveadifferenceof200Cinashortperiodoftime(5s),couldcauseseveralproblemsintheTEMstructure.Thoseweresolvedbyseveralsolutions,suchasadequatechoosingappropriateTEMmaterialandapplyingelectronicregulation.LaboratorytestingAsitwasalreadydescribed,theprototypewasproducedand(seeFig.7).Theresultsareshowing,thatthesetassump-wereconfirmed.WiththeTEMmoduleitispossibletothetemperaturedistributionondifferentpartsofthethroughoutthecycletime.Withthelaboratorytests,itasproven,thattheheatmanipulationcanbepracticallyregu-withTEMmodules.Thetestweremadeinthelaboratory,therealindustrialenvironment,withtheinjectionmachineKraussMaffeiKM60C,temperaturesen-infraredcamerasandtheprototypeTEMmodules.Theresponsein1.8svariedform+5upto80C,whatawideareafortheheatcontrolwithintheinjectioncycle.ConclusionsUseofthermoelectricmodulewithitsstraightforwardcon-betweentheinputandoutputrelationsrepresentsa45classsurfacesanditsconsequenceofplasticpartappear-canbesolved.Problemsoffillingthinlongwallscanbeedwithoverheatingsomesurfacesatinjectiontime.Further-withsuchapplicationcontroloverrheologicalpropertiespl