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1、GEARSHAFTINTRODUCTIONAbstract:Theimptantpositionofthewheelgearshaftcantfalterintraditionalmachinemodernmachines.Thewheelgearshaftsmainlyinstallthedirectionthatdeliversthedintattheprincipalaxisbox.Thepassingtoprocesstomak

2、ethemcanisdividedintomanymodelnumbersusedfmanysituationsrespectively.Sowemustbethemultilayerstotheunderstingofthewheelgearshaftinmanyways.Keywds:WheelGearShaftInthefceanalysisofspurgearsthefcesareassumedtoactinasinglepla

3、ne.Weshallstudygearsinwhichthefceshavethreedimensions.Thereasonfthisinthecaseofhelicalgearsisthattheteetharenotparalleltotheaxisofrotation.inthecaseofbevelgearstherotationalaxesarenotparalleltoeachother.Therearealsoother

4、reasonsasweshalllearn.Helicalgearsareusedtotransmitmotionbetweenparallelshafts.Thehelixangleisthesameoneachgearbutonegearmusthavearighthhelixtheotheralefthhelix.Theshapeofthetoothisaninvolutehelicoid.Ifapieceofpapercutin

5、theshapeofaparallelogramiswrappedaroundacylindertheangularedgeofthepaperbecomesahelix.Ifweunwindthispapereachpointontheangularedgegeneratesaninvolutecurve.Thesurfaceobtainedwheneverypointontheedgegeneratesaninvoluteiscal

6、ledaninvolutehelicoid.Theinitialcontactofspurgearteethisalineextendingallthewayacrossthefaceofthetooth.Theinitialcontactofhelicalgearteethisapointwhichchangesintoalineastheteethcomeintomeengagement.Inspurgearsthelineofco

7、ntactisparalleltotheaxisoftherotationinhelicalgearsthelineisdiagonalacrossthefaceofthetooth.Itisthisgradualoftheteeththesmoothtransferofloadfromonetoothtoanotherwhichgivehelicalgearstheabilitytotransmitheavyloadsathighsp

8、eeds.Helicalgearssubjecttheshaftbearingstobothradialthrustloads.Whenthethrustloadsbecomehighareobjectionablefotherreasonsitmaybedesirabletousedoublehelicalgears.Adoublehelicalgear(herringbone)isequivalenttotwohelicalgear

9、sofoppositehmountedsidebysideonthesameshaft.Theydevelopoppositethrustreactionsthuscanceloutthethrustload.Whentwomesinglehelicalgearsaremountedonthesameshaftthehofthegearsshouldbeedsoastoproducetheminimumthrustload.Crosse

10、dhelicalspiralgearsarethoseinwhichtheshaftcenterlinesareneitherparallelnintersecting.Theteethofcrossedhelicalfearshavepointcontactwitheachotherwhichchangestolinecontactasthegearswearin.Fthisreasontheywillcarryoutverysmal

11、lloadsaremainlyfinstrumentalapplicationsaredefinitelynotrecommendedfuseinthetransmissionofpower.Thereisondifferencebetweenacrossedhelicalgearahelicalgearuntiltheyaremountedinmeshwitheachother.Theyaremanufacturedinthesame

12、way.ApairofmeshedcrossedhelicalgearsusuallyhavethesamehthatisarightAshaftisarotatingstationarymemberusuallyofcircularcrosssectionhavingmounteduponitsuchelementsasgearspulleysflywheelscrankssprocketsotherpowertransmission

13、elements.Shaftmaybesubjectedtobendingtensioncompressiontsionalloadsactingsinglyincombinationwithoneanother.Whentheyarecombinedonemayexpecttofindbothstaticfatiguestrengthtobeimptantdesignconsiderationssinceasingleshaftmay

14、besubjectedtostaticstressescompletelyreversedrepeatedstressesallactingatthesametime.Thewd“shaft”coversnumerousvariationssuchasaxlesspindles.Anaxleneitherisashaftwitherstationaryrotatingnsubjectedtotsionload.Ashirtrotatin

15、gshaftisoftencalledaspindle.Wheneitherthelateralthetsionaldeflectionofashaftmustbeheldtocloselimitstheshaftmustbesizedonthebasisofdeflectionbefeanalyzingthestresses.Thereasonfthisisthatiftheshaftismadestiffenoughsothatth

16、edeflectionisnottoolargeitisprobablethattheresultingstresseswillbesafe.Butbynomeansshouldthedesignerassumethattheyaresafeitisalmostalwaysnecessarytocalculatethemsothatheknowstheyarewithinacceptablelimits.Wheneverpossible

17、thepowertransmissionelementssuchasgearspulletsshouldbelocatedclosetothesupptingbearingsthisreducesthebendingmomenthencethedeflectionbendingstress.AlthoughthevonGoodmanmethodisdifficulttouseindesignofshaftitprobablycomesc

18、losesttopredictingactualfailure.Thusitisagoodwayofcheckingashaftthathasalreadybeendesignedofdiscoveringwhyaparticularshafthasfailedinservice.Furthermethereareaconsiderablenumberofshaftdesignproblemsinwhichthedimensionare

19、prettywelllimitedbyotherconsiderationssuchasrigidityitisonlynecessaryfthedesignertodiscoversomethingaboutthefilletsizesheattreatmentsurfacefinishwhethernotshotpeeningisnecessaryindertoachievetherequiredlifereliability.Be

20、causeofthesimilarityoftheirfunctionsclutchesbrakesaretreatedtogether.InasimplifieddynamicrepresentationofafrictionclutchbraketwoinertiasI1I2travelingattherespectiveangularvelocitiesW1W2oneofwhichmaybezerointhecaseofbrake

21、aretobebroughttothesamespeedbyengagingtheclutchbrake.Slippageoccursbecausethetwoelementsarerunningatdifferentspeedsenergyisdissipatedduringactuationresultinginatemperaturerise.Inanalyzingtheperfmanceofthesedevicesweshall

22、beinterestedintheactuatingfcethetquetransmittedtheenergylossthetemperaturerise.Thetquetransmittedisrelatedtotheactuatingfcethecoefficientoffrictionthegeometryoftheclutchbrake.Thisisprobleminstaticwhichwillhavetobestudied

23、separatelyfeachgeometricconfiguration.Howevertemperatureriseisrelatedtoenergylosscanbestudiedwithoutregardtothetypeofbrakeclutchbecausethegeometryofinterestistheheatdissipatingsurfaces.Thevarioustypesofclutchesbrakesmayb

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