机械外文翻译：宽槽圆柱凸轮数控加工技术的研究

英文原文deTughColumnCamNmericalContlPcessingReseachSummar:Soequestonsproducswhichinviewofthetrditonalilingethodprocesingcolunca,proposedonekindinviewofthetoughspacouslyinthecutingtooldiaetercoluncampathnuericalcontolilingprocesingethod.Throughtheanalyisresarch,hasestblihedonekindofcorectcoordnatstrnsorationodel,andprocssesaccodingtothsconorstotherequetwidetroughcolunca.Keyords:NuericalcontolprocesingCoordnatsransorationwidthtroughcoluncamMainTextThecoluncampathisgenerllysurroundsacordngtothecetanrueintheroundcylnderandsoonthewidetough.Mustsatsybelowtothecoluncampathnuericalcontolillngprocssingrequsts:1.Thecoluncampathworkingsuracenaelytwosidesplaneofnoralsecionlinsustbestictparale;2.Thecoluncampathustwaitorthewidthintheworksecion.Thisisguaraneestherolerinthecoluncampaththestedyotionessenialcondiion.hencoluncampathwidthnotbig,ayindthecorespondingdietertheendilltocaryontheprocesingalongthetroughcavtyiddlelne,coparedwithiseasytoprocesconorstotheaboverequstcoluncampath.Accordingtotheexiteneinorationinroducdtha,atpresntthecoluncamillngprocssingallisreaizswiththseans.Becausethsethodhastooanyliitatons,bringsanydiculisortheacualillngprocesing.Forexaplewhencannotindwiththetroughwidthsieequalstandrdcutingtoo,ustcaryontothecutingtoolchangesthesyst.Regardingthetroughwidthsiebigcoluncampath,isverydiicuttoindthediaeterandthetroughwidthequalsandardcutingtool.Evenifhasthecorespondingcutingtool,butalsoustconsidrtheenginebedainaxleoutputandtheainaxleandtheworkclohesjgrigdiylit,specalyenginebedainaxlestuctuetocutingtoollit.Forexaplethenuerialcontolenginebedhostaxleneckis7:2440innercones,usesorparsJT40thetoolsyst,thenostgrealyonlycanuseφ20mendill(noattrsraghthandlebitholde).Thisregadingthetroughwidthisthe38mcouncam(isprocesingcamwhichthisaricenarate)saidisunabletoproces,ustseekthenewprocesingethod.Underandanalyestheresarchaccodingtotheexperence,inroducdonekindissalerthanthecampathwidthendillwiththediaetertocaryonthenuericalcontolprocssingtothecoluncampaththeethod,calsitthewidthtroughcoluncamnuericalcontolprocssing.Firs,ProessngcratThecoluncampathissurroundsintheroundcylnderandsoonthewidthtrough,whenisprocssingotenisbiggerthan360°.alongthecicuerencesuraceillngscopessuiableorwithtohavethenuericalcontolrotryabutentthevericalnuericalcontolillngachinetocaryontheprocesing.Accordingtothecoluncamactulstuctue,selctsthebetkeythespindeakeswhenthecamprocesingtheradaldirctonandtheweektothelocaiztondatu,akestheaxiallocaiztondatumbythespindeledg,andthenosetheadcontacsthecoluncamwiththespindeinrontofthroughthenut.Thecoluncamaxialandtheradaldirctonszeisgenealybig,inordertooveroebecusethebracktprocesestiethecutingorcecretesinthespndledisorionandtheprocesingprocssproducesinpirstrbles,usesasupporingonthetaltock,withsandsthespindecentrborewiththenuerialcontolturnpaterottionspooltheadcoaxilapextoaketheauxiirysuppoting.Thecoluncampathbaseoneachsecionusualyisandsoondeep,selctsthelatbasecolunendillprocesinggenerll.Beorethecoluncamilingprocesingusualyisasoldcicularcylnde,ustpassthroughworkingprocedueandsoonslo,roughachinng,halfpreisonwork,preisonwork;Becausethetroughcavtywidthisbig,Thereore,exceptthetroughworkingprocdureandaroughachiningworkingproceduepartofknivesposiionspathayalongbesidethetroughcaviyiddlelineproducion,otherknieposiionpathsthenustbealongthetroughcaviycentralgnentlt,arerightnearbytwoaccodingtotheCorrespondng.Figure1columncampathtwo-dimensionaldevelopedviewSecond,SolutonodelInthecoluncampathnuericalcontolprocesing,howextactsineachworkingprocduretoprocsstwosdessuacestheknieposiionpathiske.Regardingtheperpheryoncampath,usualyislaunchsirsttheroundcylnde,extactsthsworkingprocdureintheXSplanetoprocsstwosidessuracestheknieposiionpathtolaunchcurveX;Thentrnsorsthoughthecoordnats,willlaunchthecurveStrnsorationwillbeonourcoordnatesenginebedsknieposiionpath.UnderdiscusesnoatterwhatinaprocesingworkingprocdurelaunchscurveXSthesoluionethod,aswellasproducioninalknieposiionpathcoordnatestansorationethod.curveXSthesoluionLikechart2shows,Loisthecoluncampathiddlelin,regadingtheiworkingprocedue,LliandLrirepeciveythetroughcavtywhichisgoingtoprocesbethsworkingproceduelet,therighttwosidessuracelaunchsthecurv,thiswidthisBi,processesthecuttingtoolradiusisr(obviously2r≤Bi),processesthiscavitytobeleft,therightsideknieposiionpathlunchesthecurveisCLliandCLri,supposesPoisinatroughcaviyiddlelinespot,PoisthetroughcavtyiddlelineinthePoplaelawaro,Thenislet,therightknieposiionpathlunchesinthecurvecorespondngpointspliandthepricoputatonalethodis:()Figre2clncampahtwo-densioaldeeoedviwoalongthetroughcaviyiddlelineigraton,naelyayextactthisworkingprocedueknieposiionpathtolaunchcuveXSintheXOSplane;Accordingtotheprocesingworkingprocedue,changsineachworkingprocedueintuntroughwidthBi,thnextacstheprocesingtoneedthetroughcaviyallknivesposiionpathtolaunchthecurv.2.AlongcampahiddlelineproessngcoodinaestrnsorationethodAbovethecoputatonislaunchsintheplaneintheroundcylndertocaryon,inordertoextacttheprocssingcouncampathcaviytheknieposiionpath,ustlaunchtheplaneinthecurvetotrnsormtotheroundcylnderin.ThesuppostionrottingaxisorciclesXaxisAaxs,piisinaknieposiionpathknieposiionspot,itlaunhesinthecuveinthetwo-diensionalsuracethecoordnatesor(x,),onourcoodinaesenginebedscoordnatesis(x,,a.Becausethecoluncampathcavtyusualyisandsoondeep,theeore,thezcoordnatesinestblihaterdepthswhichneedstoprocss,intheprocesingisinvaiabe;Below()ntheorula,Risthecoluncamshatradus.Theprevoustypeisthepreentunivesalusecoodinaestrnsorationorula,rgardngusesthestandrdcutingtooltoprocssthecoluncamalongthecampathiddlelineillngiscorec.thequestonanalyistotheprevoustypeinthewidthtoughcoluncamprocesinghenapplestheprevoustypeprootioninthewidthtroughcoluncamnuericalcontolprocesing,hashadsoequesionsacualythroughthecoordnatestrnsorationcoputaionknieposiionpathintheactulprocesing.Finishdaterthecouncampathprocesing,inordertoexainewhetherconorstotherequreent,withthediaeterwasequaltothecoluncambowlexaineshascariesontheexainaton,discovredactullyprocssesthetroughwidthdoesnotwaitorthephenoenonwhich,hasjas.Thecarulobservtion,procssesorignalyontroughcaviyplaneofnoralsecionnotalwaysineriorwidthrecangulrtrough,butsoetiesisonunderthewidththenarowloudspekertrough.Inordrtoclaiyreaon,(2)expessedthecoordnatestrnsorationethodtotheorulatocaryonthethoroughanalyisandtheresarch.Likechart3shows,(1)ayknowbytheorula,procesesthetroughcavtytwosidessuracesknieposiionpathon-ineplandtheprspotisbythetroughcaviyiddlelneinpoequa-spcebiasbut,(2)trnsorsatertheorula,plandtheprpointcorespondencecornerisnotequaltoaPo corne,alsoisplandprcorespondingcuterbarvectorvlvlandpopointcorespondencecuterbarvectorvovonotparlel,theeore,procesesthetroughcavtyhasbecoeonundernatualythewidththenarowloudspekertrough,butisnotonineriorwidthrecangulrtoughwhichneeds.Supposesthesecionandthespoolthradincudedangleorthea,thecoluncamshatradusisR,cuterbarvectorlVl andootheangeeroris:δ＝(B/2－r)sn/R (3)a)Cylnder cam slot sketh ap b)TheA-A cutsto ace enletheskethapChart3Coluncampathprocssingscheaticdrawing(3)ayknowbytheorula,whenθ=0°,whenisthecampathiddlelneandthecolunspoolthradverial,theangleerorisazero,naelythetroughcavtyisontheinerorwidthrecangulrouth;henθ=90°,whenisthecampathiddlelineandthecolunspoolthradpaalel,theangeerorachivedbigges,thistiethetroughcaviytrupet-shapedobjectphenoenonisostserous;hen0<θ<90,alongwith θinceasng,angleerorbigge,thetupet-shpedobjectphenoenonisalsooreseious.Theactulprocssingappersthephenoenoniscopleteyconsitentwiththeaboveanaysi,thsexplinedorula(3)theanaysisisentreyaccuate.4.de trough colun cam nuericl contol procesing coordnatestrnsorationethodMayknowbytheaboveanalyis,theorula(2)cretesthecampathoronwidthunderthenarowtrupet-shapedobjectainreaonis,plandtheprpointcorespondencecornrisdeerstothesetwo,butslandsrwhichselctsownarclenghvalueslandsrcalulaesaeisnotequaltotroughcavtycentalpointpoarclenghvalueso.Therore,ifplandtheprpointcorespondencecornerdeerstotroughcavtycenralpointpoarclngthvauesotocalulae,ayelinatethskindofloudspekertoughphenoenon.Accordngtothskindofentait,aganstuctuecoordnatestrnsorationorula.o-densionallaunchsintheplneintheroundcylnde,supposesthetroughcavtyiddlelinetolaunchinthecuveaspotispo(xo,So),procssesontwosidessuracestocorespondthekniepostionspotintolaunchinthecurvethespotispl(xsl)andpr(xpr),then,thecoordnatestrnsorationorulais:()Theapplcatonorula(4)produceswhenknieposiionpathprocesingcoluncampath,thereultconorstotheabovetenaiveplancoplete,procesesthecoluncampathaleadydidnothaveonunderthewidththenarowloudspekertroughphenoenon,butwasthetueonineriorwideretangetrough.Rfn：WC,nYReserchngDesignensortheRedesignofProductFromDesignStudis2003.24(2)173-180J,LiuCerorcorectonethodorCNCachinetoolsusingreereneparansacionsofNAMRE/SME,1994.GTheachinetool taskorch.BalHarbour BalHabourHotel,1980.4.GeneFrankln FeedbackcontolofDynais.systs,4E.译文：宽槽圆柱凸轮数控加工技术的研究摘要:针对传统铣削方法加工圆柱凸轮所产生的一些问题，提出了一种针对槽宽大于刀具直径的圆柱凸轮槽的数控铣削加工方法通过分析研究建立了一种正确的坐标转换模型，并依此加工出符合要求的宽槽圆柱凸轮。关键词：数控加工 坐标转换 宽槽圆柱凸轮圆柱凸轮槽一般是按一定规律环绕在圆柱面上的等宽槽对圆柱凸轮槽的数控铣削加工必须满足以下要求1.圆柱凸轮槽的工作面即两个侧面的法截面线必须严格平行2.圆柱凸轮槽在工作段必须等宽这是保证滚子在圆柱凸轮槽中平稳运动的必要条件当圆柱凸轮槽宽度不大时可以找到相应直径的立铣刀沿槽腔中心线进行加工比较容易加工出符合上述要求的圆柱凸轮槽据现有资料介绍目前圆柱凸轮的铣削加工都是用这种办法来实现由于这种方法有太多的局限性给实际铣削加工带来许多困难例如一旦找不到与槽宽尺寸相等的标准刀具时，就必须对刀具进行改制。对于槽宽尺寸较大的圆柱凸轮槽，很难找到直径与槽宽相等的标准刀具。即使有相应的刀具还要考虑机床主轴输出功率及主轴和工装夹具刚度的限制特别是机床主轴结构对刀具的限制例如数控机床主轴头为∶24的0号内锥配用J40的工具系统则最大只能使用φ2mm的立铣刀(不论直柄还是锥柄。这对于槽宽为8m的圆柱凸轮就是本文所叙述的加工凸轮)来说是无法加工的，必须寻求新的加工方法。下面根据实践经验和分析研究介绍一种用直径小于凸轮槽宽的立铣刀对圆柱凸轮槽进行数控加工的方法，称之为宽槽圆柱凸轮的数控加工。加工工艺圆柱凸轮槽是环绕在圆柱面上的等宽槽其加工时沿圆周表面铣削的范围往往大于360°适于用带有数控回转台的立式数控铣床进行加工根据圆柱凸轮的实际结构选用带键的心轴作凸轮加工时径向和周向定位基准以心轴的台肩作轴向定位基准并用心轴前端部的螺纹通过螺母压紧圆柱凸轮圆柱凸轮的轴向和径向尺寸一般较大为了克服由于悬臂加工时切削力所造成的心轴变形和加工过程中产生的振颤使用一个支承于尾座上的与数控转台的回转轴线同轴的顶尖顶住心轴中心孔作辅助支承。圆柱凸轮槽的底部在每一个截面上通常是等深的，一般选用平底圆柱立铣刀加工。圆柱凸轮铣削加工前通常是一个实心的圆柱体，要经过开槽、粗加工、半精加工精加工等工序由于槽腔宽度较大因此除开槽工序及粗加工工序的一部分刀位轨迹可以沿槽腔的中心线生成之外其余刀位轨迹则必须是沿槽腔中心线向左、右两边按相应的距离等距偏置生成，如图1所示。图1圆柱凸轮槽的二维二、求解模型在圆柱凸轮槽的数控加工中如何求出每道工序中加工两个侧表面的刀位轨迹是其中的关键。对于圆柱表面上的凸轮槽，通常是先将圆柱面展开，在XOS平面内求出该工序加工两个侧表面的刀位轨迹的展开曲线XS；然后通过坐标转换，将展开曲线XS转换为四坐标机床上的刀位轨迹。下面讨论任一加工工序中展开曲线XS的求解方法，以及生成最后刀位轨迹的坐标转换方法。1.展开曲线XS的求解如图2所示其中Lo为圆柱凸轮槽的中心线，对于第i道工序，Lli和Lri分别为该工序将要加工的槽腔的左右两个侧表面展开曲线此槽宽为Bi加工刀具半径为r(显然2r≤Bi)加工此槽腔左右侧面的刀位轨迹展开曲线为CLli和CLri设Po为槽腔中心线上的一个点no为槽腔中心线在Po点处的法矢那么左、右刀位轨迹展开曲线上对应点Pli和Pri的计算方法为：(1)图2 圆柱凸轮槽的二维展开图将Po点沿着槽腔中心线移动即可以求出该工序刀位轨迹在XOS平面内的展开曲线XS按照加工工序依次改变每道工序中的槽宽度B，即可求出加工所需槽腔所有刀位轨迹的展开曲线。2.沿凸轮槽中心线加工的坐标转换方法以上计算是在圆柱面的展开平面内进行的，为了求出加工圆柱凸轮槽腔的刀位轨迹，必须将平面内的展开曲线转换到圆柱面上。假设转动轴为绕X轴的A轴，Pi为刀位轨迹上的一个刀位点，它在二维平面展开曲线上的坐标为(x,s在四坐标机床上的坐标为(x,z,)由于圆柱凸轮槽腔通常是等深的因此z坐标在设置为所需要加工的深度值之后在加工中是不变的；对于其余三个坐标，构造出以下坐标转换公式：(2)式中R为圆柱凸轮轴的半上式是目前普遍使用的坐标转换公式对于