资源描述:
《lathes车床 毕业设计_英语论文翻译4》由会员上传分享,免费在线阅读,更多相关内容在学术论文-天天文库。
1、┊┊┊┊┊┊┊┊┊┊┊┊┊装┊┊┊┊┊订┊┊┊┊┊线┊┊┊┊┊┊┊┊┊┊┊┊┊毕业设计(论文)报告纸LATHESThebasicmachinesthataredesignedprimarilytodoturning,facingandboringarecalledlathes.Verylittleturningisdoneonothertypesofmachinetools,andninecandoitwithequalfacility.Becauselathecandoboring,facing,drilling,andr
2、eaminginadditiontoturning,theirversatilitypermitsseveraloperationstobeperformedwithasinglesetupoftheworkpiece.Thisaccountsforthefactthatlathesofvarioustypesaremorewidelyusedinmanufacturingthananyothermachinetool.Lathesinvariousformshaveexistedformorethantwothousand
3、years.Modemlathesdatefromabout1797,whenHenryMaudsleydevelopedonewithaleadscrew.Itprovidedcontrolled,mechanicalfeedofthetool.ThisingeniousEnglishmanalsodevelopedachange-gearsystemthatcouldconnectthemotionsofthespindleandleadscrewandthusenablethreadstobecut.LatheCons
4、truction.TheessentialcomponentsofalathearedepictedintheblockdiagramofFig.15-1.Thesearethebed,headstockassembly,tailstockassembly,carriageassembly,quick-changegearbox,andtheleadscrewandfeedrod.Thebedisthebackboneofalathe.Itisusuallymadeofwell-normalizedoragedgrayorn
5、odularcastironandprovidesaheavy,rigidframeonwhichalltheotherbasiccomponentsaremounted.Twosetsofparallel,longitudinalways,innerandouter,arecontainedonthebed,usuallyontheupperside.SomemakersuseaninvertedV-shapeforallfourways,whereasothersutilizeoneinvertedVandoneflat
6、wayinoneorbothsets.Becauseseveralothercomponentsaremountedand/ormoveonthewaystheymustbemadewithprecisiontoassureaccuracyofalignment.Similarly,properprecautionshouldbetakeninoperatingalathetoassurethatthewaysarenotdamaged.Anyinaccuracyinthemusuallymeansthattheaccura
7、cyoftheentirelatheisdestroyed.Thewaysonmostmodernlathesaresurfacehardenedtooffergreaterresistancetowearandabrasion.Theheadstockismountedinafixedpositionontheinnerwaysatoneendofthelathebed.Itprovidesapoweredmeansofrotatingtheworkatvariousspeeds.Itconsists,essentiall
8、y,ofahollowspindle,mountedinaccuratebearings,andasetoftransmissiongears---similartoatrucktransmission---throughwhichthespindlecanberotatedatanumb