机械制造技术基础课件-chapter4-section1(new)

Chapter4MachineToolsandMachiningOperationsforrotationalpartsAbstractMachinepartsarebasicallyseparatedintotwo:rotationalpartsandnon-rotationalparts.Thischapterwillfocusontherequiredmachinetools,cuttingtoolsandmachiningoperationsforrotationalparts.Thelathesandlathecuttingtools,includingmainmechanismofCA6140andthestructureofturningtoolsareintroduced.Inthesametime,theworkprincipleofthemachiningmethodsofgrinding,somehole-producedmachinesandcuttingtools,arealsointroduced.machiningofrotationalparts(a)TrackMachining(b)formingmethodKeywords•Nameofmachinetools:Lathe(车床),screwthreadmachine(螺纹机床),Grindingmachine(磨床),boringmachine(镗床),drillingmachine(钻床),broachingmachine(拉床).•Methodsofshapegeneration:Turning,Taperturning,boring（镗孔）,drilling,coredrilling（扩孔）,counterboring（锪孔）,reaming（绞孔）,grinding,Knurling（滚花）,threadingLatheGrindingMachineDrillPress4.1Lathesandlathecuttingtools4.2Grindingmachines4.3HolemakingmachinetoolandcuttingtoolIndex4.4Processanalysisofrotationalparts4.1LatheandLatheCuttingTools4.1.1turningoperationLatheismainlyusedtoproducepartsinroundshape.Itremovesmaterialbyrotatingtheworkpieceagainstasingle-pointcutter,whilethelatterfeedslinearly.Operationsthatcanbeperformedonalathe:a).Straightturningb).Taperturningc).Profilingd).Facinge).Turningandexternalgroovingf).Facegroovingg).Formcuttingh).Boringi).Drillingj).Cuttingoffk).Threadingl).KnurlingLet’stakeCA6140latheastheexample.Itisverytypicalamongthecommonlathes.Typicalmachiningbylathediscussion•Thinkabout:Couldanon-rotationalpartbemachinedbyturningmethod?Why?Typesoflathe：1.普通车床、落地车床；(Enginelathe/groundlathe)2.立式车床；(Verticallathe)3.转塔（六角）车床；(Turretlathe)4.多刀半自动车床；(Semi-automaticlathe)5.仿形车床及仿形半自动车床；(Profilinglathe)6.单轴自动车床；(single-axisautomaticlathe)7.多轴自动车床及多轴半自动车床；(Multi-axisautomaticlathe)8.专门化车床(special-purposelathe)CA6140型普通车床外形图(3)ThemainstructureofCA6140①HeadstockMainfunctions:Supporting,driving,stopping,changingdirection,braking,andchangingthespeedoftheprincipleaxis，andtransferringthemotionfromtheprincipleaxistothefeedsystem.Mainmechanismandparts:theunloadbeltcarrier,bi-directionalmulti-chipfrictionalclutchandspeedchangeoperatingmechanism.TheHeadstockstructureofCA6140②Apron（溜板箱）Mainfunctions:transferthefeedorrapidmovementmotionfromfeedboxorquick-movedmotortothecarriage,andmakethecarriagemovelongitudinallyandtransversallyinpositiveornegativedirection.Themainmechanism：apairofhalfnuts,feedmechanisminlongitudinalandtransversaldirection,operatingmechanismforquickmove,lockmechanism,safeclutch.4.1.2TypesandthemaintechnicalParametersofLathemaintechnicalParametersofLathea)Max.diametertobeturnedb)Maximumdistancebetweenheadstockandtailstockc)Powerofmainmotord)MaximumrotationspeedthetypesofLathea)copyinglatheb)automaticlathec)threadcuttinglathed)turretlathee)CNCLatheOtherLathesturretLatheCNCLathe4.1.4lathecuttingtoolmaintypesofturningtool1-facingcutter；2-profilingcutter；3-groovingcutter；4-externalcylindricallathecutter；5-threadingcutterItisusedtomachineroundparts,innerholes,endsurface,thread,andtooth.Themaintypesareshownas:Lathetoolcanbedivideintointegralturningtool、weldedtool、clampedtoolandrotation-abletoolaccordingtothestructure.Classificationandcomparisonofturningtool：weldedtoolAdvantage：simplestructure、compact；rigidity、shockresistance;easytoproduceanduse.disadvantage：worsecapabilityofcutting、non-recycledtoolbar、longersetuptime.Rotation-abletoolAdvantage：longtoollife,highefficiency,helptospreadnewtechniqueandtechnologyandlowertoolcost.Attention:position(accurateornot),clamping(secureornot),chipflow(smoothornot),changeandsetup(easyornot)Machine-ClampedtoolFormingtoolAdvantage：recycledtoolbar,longtoollifeAttention:position(accurateornot),clamping(secureornot),chipflow(smoothornot)Advantage：highefficiency,easytouseAttention:difficulttoproduce,highertoolcost4.1.5lathefixturesorturningfixtures