故障的分析、尺寸的決定以及凸輪的分析和應(yīng)用-畢業(yè)設(shè)計外文翻譯

1、FailureFailureAnalysisAnalysis，DimensionalDimensionalDeterminationDeterminationAnalysisAnalysis，ApplicationsApplicationsOfOfCamsCamsJackBaubleAbstractAbstract：Itisabsolutelyessentialthatadesignengineerknowhowwhypartsfail

2、sothatreliablemachinesthatrequireminimummaintenancecanbedesigned；CamsareamongthemostversatilemechanismsavailableAcamisasimpletwomemberdeviceTheinputmemberisthecamitself，whiletheoutputmemberiscalledthefollowerThroughtheus

3、eofcams，asimpleinputmotioncanbemodifiedintoalmostanyconceivableoutputmotionthatisdesiredKeyKeywds:wds:failurehighspeedcamsdesignpropertiesINTRODUCTIONINTRODUCTIONItisabsolutelyessentialthatadesignengineerknowhowwhypartsf

4、ailsothatreliablemachinesthatrequireminimummaintenancecanbedesignedSometimesafailurecanbeserious，suchaswhenatireblowsoutonanautomobiletravelingathighspeedOntheotherh，afailuremaybenomethananuisanceAnexampleisthelooseningo

5、ftheradiathoseinanautomobilecoolingsystemTheconsequenceofthislatterfailureisusuallythelossofsomeradiatcoolant，aconditionthatisreadilydetectedcrectedThetypeofloadapartabsbsisjustassignificantasthemagnitudeGenerallyspeakin

6、g，dynamicloadswithdirectionreversalscausegreaterdifficultythanstaticloads，therefe，fatiguestrengthmustbeconsideredAnotherconcerniswhetherthematerialisductilebrittleFexample，brittlematerialsareconsideredtobeunacceptablewhe

7、refatigueisinvolvedManypeoplemistakinglyinterpretthewdfailuretomeantheactualbreakageofapartHowever，adesignengineermustconsiderabroaderunderstingofwhatappreciabledefmationoccursAductilematerial，howeverwilldefmalargeamount

8、pritoruptureExcessivedefmation，——AutomaticdishwashersThecontourofhighspeedcams(camspeedinexcessof1000rpm)mustbedeterminedmathematicallyHowever，thevastmajityofcamsoperateatlowspeeds(lessthan500rpm)mediumspeedcamscanbedete

9、rminedgraphicallyusingalargescalelayoutIngeneral，thegreaterthecamspeedoutputload，thegreatermustbetheprecisionwithwhichthecamcontourismachinedDESIGNDESIGNPROPERTIESPROPERTIESOFOFMATERIALSMATERIALSThefollowingdesignpropert

10、iesofmaterialsaredefinedastheyrelatetothetensiletestStaticStaticStrengthStrengthThestrengthofapartisthemaximumstressthatthepartcansustainwithoutlosingitsabilitytoperfmitsrequiredfunctionThusthestaticstrengthmaybeconsider

11、edtobeapproximatelyequaltotheproptionallimit，sincenoplasticdefmationtakesplacenodamagetheeticallyisdonetothematerialStiffnessStiffnessStiffnessisthedefmationresistingpropertyofamaterialTheslopeofthemodulusline，hence，them

12、odulusofelasticityaremeasuresofthestiffnessofamaterialResilienceResilienceResilienceisthepropertyofamaterialthatpermitsittoabsbenergywithoutpermanentdefmationTheamountofenergyabsbedisrepresentedbytheareaunderneaththestre

13、ssstraindiagramwithintheelasticregionToughnessToughnessResiliencetoughnessaresimilarpropertiesHowever，toughnessistheabilitytoabsbenergywithoutruptureThustoughnessisrepresentedbythetotalareaunderneaththestressstraindiagra

14、m，asdepictedinFigure28bObviously，thetoughnessresilienceofbrittlematerialsareverylowareapproximatelyequalBrittlenessBrittlenessAbrittlematerialisonethatrupturesbefeanyappreciableplasticdefmationtakesplaceBrittlematerialsa

15、regenerallyconsideredundesirablefmachinecomponentsbecausetheyareunabletoyieldlocallyatlocationsofhighstressbecauseofgeometricstressraiserssuchasshoulders，holes，notches，keywaysDuctilityDuctilityAductilitymaterialexhibitsa