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1、毕业设计译文题目:矿井提升及总体设计学生姓名:杜雨航准考证号:080112200473指导老师:张冬梅2012年LATHESThebasicmachinesthataredesignedprimarilytodoturning,facingandboringarecalledlathes.Verylittleturningisdoneonothertypesofmachinetools,andninecandoitwithequalfacility.Becauselathecandoboring,facing,drilling,and
2、reaminginadditiontoturning,theirversatilitypermitsseveraloperationstobeperformedwithasinglesetupoftheworkpiece.Thisaccountsforthefactthatlathesofvarioustypesaremorewidelyusedinmanufacturingthananyothermachinetool.Lathesinvariousformshaveexistedformorethantwothousandyear
3、s.Modemlathesdatefromabout1797,whenHenryMaudsleydevelopedonewithaleadscrew.Itprovidedcontrolled,mechanicalfeedofthetool.ThisingeniousEnglishmanalsodevelopedachange-gearsystemthatcouldconnectthemotionsofthespindleandleadscrewandthusenablethreadstobecut.LatheConstruction.
4、TheessentialcomponentsofalathearedepictedintheblockdiagramofFig.15-1.Thesearethebed,headstockassembly,tailstockassembly,carriageassembly,quick-changegearbox,andtheleadscrewandfeedrod.Thebedisthebackboneofalathe.Itisusuallymadeofwell-normalizedoragedgrayornodularcastiron
5、andprovidesaheavy,rigidframeonwhichalltheotherbasiccomponentsaremounted.Twosetsofparallel,longitudinalways,innerandouter,arecontainedonthebed,usuallyontheupperside.SomemakersuseaninvertedV-shapeforallfourways,whereasothersutilizeoneinvertedVandoneflatwayinoneorbothsets.
6、Becauseseveralothercomponentsaremountedand/ormoveonthewaystheymustbemadewithprecisiontoassureaccuracyofalignment.Similarly,properprecautionshouldbetakeninoperatingalathetoassurethatthewaysarenotdamaged.Anyinaccuracyinthemusuallymeansthattheaccuracyoftheentirelatheisdest
7、royed.Thewaysonmostmodernlathesaresurfacehardenedtooffergreaterresistancetowearandabrasion.Theheadstockismountedinafixedpositionontheinnerwaysatoneendofthelathebed.Itprovidesapoweredmeansofrotatingtheworkatvariousspeeds.Itconsists,essentially,ofahollowspindle,mountedina
8、ccuratebearings,andasetoftransmissiongears---similartoatrucktransmission---throughwhichthespindlecanberotateda