液压夹具设计手册.ppt

液压夹具设计手册,思诚机电,2,GoodFixtureDesign,Goodfixturesposition,clampandsupportworkpiecesinthemosteffectivewaypossible,3,Fixturedesign,workpieceExample1,4,Fixturedesign,process,5,Datum,Fixturedesign,workpiecedatums,6,Fixturedesign,supporting,7,Fixturedesign,positioning,8,Fixturedesign,clamping,9,Fixturedesign,additionalsupportandclamping,10,Fixture,positioning,supportingandclamping,11,Fixturedesign,workpiece,Example2,12,Fixturedesign,process,13,Fixturedesign,supporting,14,Fixturedesign,clamping,X,X,15,Fixturedesign,clamping,16,Fixturedesign,positioningandclamping,17,Fixturedesign,positioning,supporting&clamping,18,Frictionclamping,Ifclampingusingfrictiononlyitmustberememberedthatthecoefficientoffriction()isnormallycalculatedat0.1,Totalclampingforce=F,19,Frictionclamping,Ifclampingusingfrictiononlyitmustberememberedthatthecoefficientoffriction()isnormallycalculatedat0.1Thiscanbeimprovedonsoftmaterials(eg.Al)iftheclampingpistonhasenoughforcetopenetratetheworkpiece,20,Fixturedesign,DEFINITIONOFACLAMPINGFORCETheforceactingonaworkpiecetobeclamped,islargeenoughtoholdtheworkpiecefirmlyinitsgivenpositionrelativetothecuttingtool,againsttheactionofthemachiningforces,21,Fixturedesign,CLAMPINGFORCESMechanicallowcost,relativelylowforcesPneumatichighercost,relativelylowforces,largecomponentsHydraulichigherinitialcost,highforces,reliable,smallcomponents,22,MechanicalForces,Maximumclampingforceusingstandardwrench,Clampingforce(kN),Clampingforcewithextensionpiecesasshown,500Ntorque,=0.1,23,StandardclampingstrapM20threadMax.recommendedtorque223NmMax.clampingforce28kN,Hydraulicswingclamp6951F-11-21(page63,metriccatalogue)22rod,76mmlongarmMax.oilpressure23MPaClampingforce7.3kN,Forcecomparison,24,Forcecomparison,StandardclampingstrapM20threadMax.recommendedtorque223NmMax.clampingforce28kN,Hydraulicswingclamp6951F-11-21(page63,metriccatalogue)22rod,clampingstrapMax.oilpressure35MPaClampingforce13.7kN,25,StandardclampingstrapM24threadMax.recommendedtorque383NmMax.clampingforce40kN,Hydraulicswingclamp6951FN-33-21(page71,metriccatalogue)38rod,clampingstrapMax.oilpressure35MPaClampingforce35kN,Forcecomparison,26,StandardclampingstrapM24threadMax.recommendedtorque383NmMax.clampingforce40kN,Hollowpistoncylinder6921-100 x10(page26,metriccatalogue)M24threadMax.oilpressure400barClampingforce101kN,Forcecomparison,27,MechanicalorHydraulic?,28,MechanicalorHydraulic?,29,Forcediagram,30,Component&Fixturedesign,SENSIBLEUSEOFFORCESensibleintroductionofpositioning,clampingandsupportingforceswillenhancethequalityofaworkpiece,31,Oilsupplytofixtures,2basicmethodsthroughpipesthroughgundrilledchannelsMethoddependsoncosttargetcomplexityoffixtureproductsbeingused,32,Oilsupplytofixtures,costcomparison,A:ThroughpipesusingflangetypeclampsB:ThroughpipesusingthreadedtypeclampsC:Throughgundrilledchannels&manifoldmountedtypeclampsD:Throughgundrilledchannels&threadedbodytypeclamps,33,Oilsupplytofixtures,costcomparison,A:ThroughpipesusingflangetypeclampsRelativelyeasytomanufactureFittingsweakestpartofsystemChiptrapsControlfixtureCOST100%,34,Oilsupplytofixtures,costcomparison,B:ThroughpipesusingthreadedtypeclampsLessswarftrapsReducesmachiningareaFittingsweakestpartofsystemCOST?%againstcontrolfixture,35,Oilsupplytofixtures,costcomparison,C:Throughgundrilledchannels&manifoldmountedtypeclampsMaximumcomponentdensityMinimumswarftrapsCOST?%againstcontrolfixture,36,Oilsupplytofixtures,costcomparison,D:Throughgundrilledchannels&threadedbodytypeclampsMaximumcomponentdensityMinimumswarftrapsCOST?%againstcontrolfixture,37,Oilsupplytofixtures,costcomparison,C:Throughgundrilledchannels&manifoldmountedtypeclamps98%,Hydrauliccircuitdesign,39,Circuitdesign,40,CamCoverfixtureexample,41,Circuitdesign,42,http:/www.ec-,43,Barrelfixtureexample,44,Circuitdesign,45,Gettingtheoiltothefixture,47,Rotary&RotaryValveCouplings,48,RotaryCouplings,UsedwhenfreepassageofoilisrequiredtobedistributedonrotarytablearrangementsStandardversionsofsingle,twin,fourandsixpassageswith/withoutleakageportMaximumoperatingpressure250/500barWhenspecifyingincludedataonrotationspeed,pressure,temperature,mediaandcycletimeSpecialdesignsavailableonrequest,49,Twinpassagerotarycoupling,Useonrotarytablewithtwosingleactingcylinders,50,Fourpassagerotarycoupling,Useonrotarytablewith4singleactingor2doubleactingcylinders,51,Sixpassagerotarycoupling,Useonrotarytableswithcombinationofupto6oilfeedsie.6s/a,3d/a,2d/a&2s/acylinders,52,RotaryCouplingcircuit,Singleactingcircuit,Doubleactingcircuit,53,Applicationexample,54,RotaryValveCouplings,Usedonrotarytablearrangementswhenloading/unloadingofstationsisrequiredwhilstmaintainingclampingpressureonremainingstationsVersionsinclude5,6,7,8,9&10stations.Applicationsrequiring2,3or4stationsuse6&8stationswithunusedportsplugged.SpecialdesignsavailableUpto200baranaccumulatorisrecommended,above200baritisessentialduetointernalleakagewithintheoilreturncavityoftheunit,55,Rotaryvalvecouplingfunction,56,RotaryValveCouplingcircuit,Singleacting,Doubleacting,57,Applicationexample,58,Couplingunits,QuickdisconnectcouplingsOne-handoperationquickdisconnectCouplingunitsAutomaticcouplingsystemsThreadedcouplingelements,59,QuickDisconnectCouplingsMaxoperatingpressure500barOnehandoperationAlwaysusedustcaps,Couplingunits,60,CouplingUnitsSingleordoubleactingIntegralaccumulatorandpressuregaugeMulti-couplerunitsavailable,Couplingunits&accumulators,61,CouplingSystemsAlwaysuseaccumulatorsonstaticsystems10temperaturedifferencerelatesto10barpressuredifference,Couplingunits&accumulators,62,Threadedcouplingelements,Breathing,64,Whatisbreathing?,Breathingistheactionofsingleactingcylindersduringthespringreturnpartofthecomponentcycle,65,Whybreathinghastobemade,ExcesspressureorvacuuminthespringareachangesthespringforceswhichleadstomalfunctionFormationofcondensationwaterpromotesrustformationandcanleadtoacompletefailureoftheelementsLeakageofhydraulicsealsmustdrainofftoexteriorwithoutpressureotherwisetherewillbemalfunctionsDustandchipsareretainedbysinteredmetalairfiltersLiquidscanbedrawnthroughthesinteredmetalfilter,thusthebreathingspringareaisreduced,ahigherexcesspressureorvacuumiscausedandthefunctionisimpaired,66,Whatisbreathing?,Whathappensduringbreathing,67,Precautions,CoverClampingelementswithoutbreatherportscanbecovered.DuetohighcoolantpressureandflowthisisnotalwayssuccessfulConsiderusingdoubleactingelementswhereverpossible,68,Precautions,BreatherhoseConnectionofabreatherhoseisapprovediftheoutletissitedatapointwherenoliquidcanpenetrateEnsurenofluidtrapsinhose,69,Precautions,ClosedbreathersystemSpringareaisincreasedbyconnectionofadditionalclosedarea.ElectricaldiecastboxesareidealVolumeofadditionalareashouldbe10timesthestrokevolumeofallconnectedcomponents,70,Systembleeding,