外文翻译--链轮的制造方法.doc

GearmanufacturingmethodsAbstractThispaperdealswiththeproductionprocessofthechainwheel.ItDetaileddescriptionofgearplanning,gearshaping,gearhobbing,gearbroaching,gearshaving,geargrinding,andintroducetheteethoftheproductionofavarietyofmethodsandtheusedoccasions.KeyWordsgearplanning,gearshaping,gearhobbing,gearbroaching,gearshaving,geargrinding,GearPlaningtheshapeofthespacebetweengearteethiscomplexandvarieswiththenumberofthegearaswellastoothmodule,somostgearmanufacturingmethodsgeneratethetoothflankinsteadofforming.Gearplaningusesareciprocatingracks,strokinginthedirectionofthehelixonagearwithagradualgenerationoffromastherackeffectivelyrollsroundthegearblank.Therackisrelievedoutofcontactforthereturnstrokeasinnormalshapingorplanning.Ithasthegreatadvantagethatthecuttingtoolsisasamplingrackwith(nearing)straightsidedteethwhichcaneasilybegroundaccurately.Thismethodislittleusedforhighproductionbecauseitisrelativelyslowinoperationduetothehightoolandslidemass；forjobbingpurposetheslowstrokingratedoesnotmatterandlowtoolcostgiveanadvantagewhereunusualsizesorprofilemodificationarerequired.Gearshapinggearshapingisinherentlysimilartogearplanningbutusesacircularcutterinsteadofarackandtheresultingreductioninthereciprocatinginertiaallowsmuchhigherstrokingspeed；moderngearshaperscuttingcargearscanrunat2000cuttingstrokesperminute.Theshapeofthecutterisroughlythesameasaninvolutegearbutthetipsoftheteetharerounded.Thegeneratingdrivebetweencutterandworkpiecedoesnotinvolvearackorleadscrewsinceonlycircularmotionisinvolvearackorleadscrewsinceonlycircularmotionisinvolved.Thetoolandworkpiecemovetangentiallytypically0.5mmforeachstrokeofthecutter.onthereturnstrokethecuttermustberetractedabout1mmtogiveclearanceotherwisetoolruboccursonthebackstrokeandfailureisrapid.Theadvantageofgearshapingarethatproductionratesarerelativelyhighandthatisthepossibletocutrightuptoashoulder.Unfortunately,forhelicalgears,ahelicalguideisrequiredtoimposearotationalmotiononthestrokingmotion；suchhelicalguidescannotbeproducedeasilyorcheaplysothemethodisonlysuitableforlongrunswithhelicalgearssincespecialcutterandguidesmustbemanufacturedforeacheachdifferenthelixangle.agreatadvantageofgearshapingisitsabilitytocutannulargearssuchasthoserequiredforlargeepicyclicdrives.GearHobbinggearhobbing,themostusedmetalcuttingmethod,usestherackgeneratingprinciplebutavoidsslowreciprocationbymountingmangy“racks”onarotatingcutter.the“racks”aredisplacedaxiallytofromagashedworm.Metalremovalratesarehighsincenoreciprocationofhoborworkpieceisrequiredandsocuttingspeeds40m/mincanbeusedforconventionalhobsandupto150m/minforcarbidehobs.Typicallywitha100mmdiameterhobtherotationspeedwillbe100rpmandsoatwentytoothworkpiecewillrotateat5rpm.Eachrevolutionoftheworkpiecewillcorrespondto0.75mmfeedsothehobwilladvancethroughtheworkpieceatabout4mmperminute.forcarproductionroughingmultiplestarthobscanbeusedwithcoarsefeedof3mmperrevolutionsothat100rpmonthecutter,atwo-starthoband20toothgearwillgiveafeedrateof30mm/minute.GearBroachingGearbroachingisnotusuallyusedforhelicalgearsbutisusedforinternalsourgears；theprincipleusedofbroachinginthecontextisforinternalsplineswhichcannoteasilydemadebyanyothermethod.Aswithallbroachingthemethodisonlyeconomicforlargequantitiessincesetupcostsarehigh.Gearbroachinggivehighaccuracyandlowsurfaceroughnessbutlikeallcuttingprocessesislimitedto“soft”materialswhichmustbesubsequentlycase-hardenedorhaettreated,givingdistortion.GearShavingGearshavingisusedasfinishingprocessesforgearsinthe“soft”state.Theobjectiveistoimprovesurfaceroughnessandprofilebymatingtheroughed-outgearwitha“cutter”whichwillimproveform.Agearshavingcutterlookslikeagearwhichhasextraclearanceattheroot(forswarfandcoolantremoval)andwhosetoothflankshavebeengroovedtogivecuttingedges.Itisrunmeshwiththeroughgearwithcrossedaxessothatthereisintheorypointcontactwitharelativevelocityalongtheteethgivingscrapingaction.Thegearshavingcuttertootharerelativelyflexibleinbendingandsowillonlyoperateeffectivelywhentheyareindoublecontactbetweentwogearteeth.Thegearandcutteroperateathighrotationspeedswithtraversingoftheworkfaceandabout100micronofmachinesarenotexpensivebutcutteraredelicateanddifficulttomanufactureGearGrindingGeargrindingisextremelyimportantbecauseitisthemainwayhardenedgearsaremachined.whenhighaccuracyisrequireditisnotsufficienttopre-correctforheattreatmentdistortionandgrindingisthennecessary.Thesimplestapproachtogearisformgrinding.Thewheelprofitisdressedaccuratelytoshaperequiredusingsinglepointdiamondswhicharecontrolledbytemplatescuttotheexactshaperequired.Theprofiledwheelisthenreciprocatedaxiallyalongthegear,whenonetoothshapehasbeenfinished,involvingtypically100micronmetalremoval,thegearisindexedtothenexttoothspace.Thismethodisfairlyslowbutgiveshighaccuracyconsistently.Settingupislengthybecausedifferentdressingtemplatesarechanged.Thefastestgeargrindingmethodusedtheprincipleasgearhobbingbutreplaceagashedandrelivedbyagrindingwheelwhichisarackinsection.Onlysinglestartwormarecutonthewheelbutgearrotationspeedsarehigh,100rpmtypically,soitisdifficulttodesignthedrivesystemtogiveaccuracyandrigidity.Accuracyoftheprocessisreasonablyhighalthoughthereisatendencyforwheelandworkpiecetodeflectvariablyduringgrindingsothewheelfrommayrequiredcompensationformachinedeflectioneffectes.Generationofawormshapeonthegrindingwheelisaslowprocesssinceadressingdiamondmustnotonlyformtherackprofilebuthastomoveaxiallyasthewheelrotates.Oncethewheelhasbeentrued,gearscanbegroundrapidlyuntilredressingisrequired.Thisisthemostpopularmethodforhighproductionrateswithsmallgears.链轮的制造方法摘要：这篇文章主要介绍了链轮的制造过程，详细地叙述了刨齿，插齿，滚齿，拉齿，剃齿，磨齿；并且详细地介绍了各种制作方法的利弊和运用场合。关键词：刨齿，插齿，滚齿，拉齿，剃齿，磨齿链轮齿间的空间形状是复杂的,而且随着齿轮的齿数和模数的不用而变化，因此大多数的链轮制造方法采用战成尺郭而不是成形加工。刨齿是采用往复运动的齿条刀，当齿条刀绕链轮胚料滚切并延其螺旋线方向运动时，齿形就会被逐渐展成。与普通的刨削加工相同，在回程中齿条刀与齿轮脱离接触。这种加工方法最大的好处是，刀具为具有直线齿形或者接近于直线齿形的齿条，其齿面易于进行精确加工。由于刀具和滑枕的质量较大，造成