数控技术概述课件

数控技术概述课件1.Chapter1

INTRODUCTIONTONUMERICALCONTROL

1.1、FundamentalofNCTechnology1.2、ClassificationsofNCMachines1.3、FeaturesofNumericalControlandItsApplicationAreas.Chapter1INTRODUCTIONTON2CourseDescription:�NCisoneofthemostimportantachievementsinmechanicalengineeringfieldin20century.�Itisacrossingandintegratingtechnologycomprisingofcomputertechnology,automaticcontroltechnology,informationtechnology,sensetechnology,andmachiningtechnology.�NumericalControlTechnologyhasbecameoneoftheimportanttechnicalbasicclassesofmechanicalengineeringspecialty.CourseDescription:�NCisone3ToshibaeventsToshibaevents4.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.1、DevelopmentHistoryofNC

1946-thefirstcomputerappearedintheworld,whichliftthecurtainonthemankindintoinformationtime.

1948-ParsonsCorporationbroughtforwardusingcomputertocontrolmachinewhentheymachinedthesurfacecontoursofairfoilshape.ParsonsCorporationwasamini-helicoptermanufacturer.Themachiningaccuracyoftheairfoilshapewas±0.0381mm.Chapter1INTRODUCTIONTON5.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.1、DevelopmentHistoryofNC

UnderthesupportbytheU.SAirForceResponsedbytheServomechanismsLaboratoryattheMIT(MassachusettsInstituteofTechnology).Chapter1INTRODUCTIONTON6.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.1、DevelopmentHistoryofNC

Threeyearslater,in1952

MITandParsonsCorporationcooperatedwitheachother,anddevelopedthefirstNCmachinewhichnamedCincinnatiHydrotelmillingmachine.Background,timeandplace.Chapter1INTRODUCTIONTON7.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.1、DevelopmentHistoryofNCThefirstgeneration,1952~1955vacuumtubes,electricalrelaysandcomplicatedmachinecontrolinterfaces.Thesecondgeneration,1955~1959miniatureelectronictubes,transistors.Thethirdgeneration,1959~1965smallscaleintegratedcircuits..Chapter1INTRODUCTIONTON8.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.1、DevelopmentHistoryofNCAbovethreegenerations,

theirNCfunctionswereperformedbyhardware(electroniccircuits),sowecallthem“hardwiredNC”(硬线数控)

1955

1959

1965.Chapter1INTRODUCTIONTON9.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.1、DevelopmentHistoryofNCThefourthgeneration,1970s(1970~1974)minicomputers.(CNC)Thefifthgeneration,1974-microprocessor.1979(VLIC)(MCNC)1994~PC-NC..Chapter1INTRODUCTIONTON10.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.1、DevelopmentHistoryofNCAfterthefourthgenerations,

theirNCfunctionswereperformedbysoftware(basedoncomputer),sowecallthem“softwiredNC”or“computernumericalcontrol”(计算机数控CNC)

1970

1974

1994.Chapter1INTRODUCTIONTON11.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.2ConceptofNCandCNC1、NC(NumericalControl,数字控制)

NumericalControl（NC）isaformofprogrammableautomationinwhichthemechanicalactionsofamachinetoolorothermachinesarecontrolledbyaprogramcontainingcodedalphanumericdata..Chapter1INTRODUCTIONTON12.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.2ConceptofNCandCNC2、NumericalControlTechnology,(数控技术)

ItmeansthetechnologywhichadoptsNCmethodstocontrolaworkprocesstorealizetheautomation..Chapter1INTRODUCTIONTON13.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.2ConceptofNCandCNC3、NumericalControlMachineTools,(数控机床)

Itis

akindofmachinetools

whichadoptsthenumericalcontroltechnologytorealizetheworkprocessautomation.ItisatypicalexampleofNCapplication..Chapter1INTRODUCTIONTON14.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.2ConceptofNCandCNC4、NumericalControlSystem,(数控系统)

Itis

theequipmentwhichcanrealizethenumericalcontrol..Chapter1INTRODUCTIONTON15.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.2ConceptofNCandCNC5、CNC(ComputerNumericalControl,计算机数控)

Themachinecontrolunitsarebasedoncomputertechnology..Chapter1INTRODUCTIONTON16.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.3BasicComponentsofNCMachineTools

Thecontrolsystemofanumericallycontrolledmachinetoolcanhandlemanytaskscommonlydonebytheoperatorofaconventionalmachine.Thesystemhastheabilitytoperformthecontrolfunctionsthroughthenumericalinputinformation,whichisthecontrolprogram,alsocalledthepartprogram..Chapter1INTRODUCTIONTON17.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.3BasicComponentsofNCMachineToolsTheworkprocessofNCisshownastherightfigure.PartdrawingPartprogramControlcomputerServo-driveunitMachinetoolPartFirstly,thepartprogrammershouldstudythepartdrawingandtheprocesschart..Chapter1INTRODUCTIONTON18.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.3BasicComponentsofNCMachineToolsTheworkprocessofNCisshownintherightfigure.PartdrawingPartprogramControlcomputerServo-driveunitMachinetoolPartThenthepartprogrammershouldpreparethecontrolprogramonastandardforminthespecifiedformat.Itcontainsallthenecessarycontrolinformation.Chapter1INTRODUCTIONTON19.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.3BasicComponentsofNCMachineToolsTheworkprocessofNCisshownintherightfigure.PartdrawingPartprogramControlcomputerServo-driveunitMachinetoolPartNextthepartprogramistransferredintothecontrolcomputer(MDI).thecomputerconvertseachcommandintothesignalthattheservo-driveunitneeds.Chapter1INTRODUCTIONTON20.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.3BasicComponentsofNCMachineToolsTheworkprocessofNCisshownintherightfigure.PartdrawingPartprogramControlcomputerServo-driveunitMachinetoolPartAtlast,theservo-driveunitdrivesthemachinetooltomanufacturethefinishedpart.Chapter1INTRODUCTIONTON21.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.3BasicComponentsofNCMachineTools

AtypicalNCmachinetoolhasfivefundamentalunits:(1)theinputmedia;(2)themachinecontrolunit;(3)theservo-driveunit;(4)thefeedbacktransducer;(5)themechanicalmachinetoolunit.Chapter1INTRODUCTIONTON22.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.3BasicComponentsofNCMachineTools

Thegeneralrelationshipamongthefivecomponentsisillustratedinthebelow.MachineControlunitInputmediaServo-driveMachinetoolFeedbackTransducer.Chapter1INTRODUCTIONTON23.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.3BasicComponentsofNCMachineToolsMachineControlunitInputmediaServo-driveMachinetoolFeedbackTransducerTheinputmediacontainstheprogramofinstructions,itisthedetailedstep-by-stepcommandsthatdirecttheactionsofthemachinetool;theprogramofinstructionsiscalledapartprogram..Chapter1INTRODUCTIONTON24.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.3BasicComponentsofNCMachineToolsMachineControlunitInputmediaServo-driveMachinetoolFeedbackTransducerTheprogramiscodedonasuitablemediumforsubmissiontothemachinecontrolunit.Thecommonmediuminthepastispunchedtape,magnetictape:.Chapter1INTRODUCTIONTON25.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.3BasicComponentsofNCMachineToolsMachineControlunitInputmediaServo-driveMachinetoolFeedbackTransducerNow,Thecommonmediumisdiskette,electronictransferfromacomputer(RS232C):.Chapter1INTRODUCTIONTON26.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.3BasicComponentsofNCMachineToolsMachineControlunitInputmediaServo-driveMachinetoolFeedbackTransducer

MCUconsistsofamicrocomputerandrelatedcontrolhardwarethatstorestheprogramofinstructionsandexecutesitbyconvertingeachcommandintomechanicalactionsofmachinetool,onecommandatatime.theMCUincludessystemsoftware,calculationalgorithm,andtransitionsoftwaretocoverttheNCpartsprogramintoausableformatfortheMCU.Chapter1INTRODUCTIONTON27.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.3BasicComponentsofNCMachineToolsMachineControlunitInputmediaServo-driveMachinetoolFeedbackTransducerSpindleandfeeddrivemotorsandtheirservo-amplifiersarethecomponentsoftheservo-driveunit.TheMCUprocessesthedataandgeneratesdiscretenumericalpositioncommandsforeachfeeddriveandvelocitycommandforthespindledrive.ThenumericalcommandsareconvertedintosignalvoltagebytheMCUunitandsenttoservo-amplifiers,whichprocessandamplifythemtothehighvoltagelevelsrequiredbythedrivemotors.Thedrivesinmachinetoolsareclassifiedasspindleandfeeddrivemechanisms..Chapter1INTRODUCTIONTON28.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.2CLASSIFICATIONSOFNCMACHINENumericalcontrolmachinesareclassifiedindifferentway:(1)ThetypesofNCmotioncontrolsystem;(2)Thetypeofservo-drivesystem;(3)ApplicationofNC.Chapter1INTRODUCTIONTON29.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.2.1TypesofNCMotionControlSystemMotioncontrolsystemsforNCcanbedividedintotwotypes:(1)Point-to-pointcontrolsystem(点位控制系统);(2)Continuous(Contouring)pathcontrolsystem;（连续控制或轮廓控制系统）.Chapter1INTRODUCTIONTON30.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.2.1TypesofNCMotionControlSystemPoint-to-pointcontrolsystemPoint–topoint(positioning)controlinNCItisalsocalledPositioningcontrolsystem,Whichmovestheworktabletoaprogrammedlocationwithoutregardtothepathtakentogettothelocation.Thatistosay,thepathbetweenpointsisoflittleconcernandisnotparticularlycontrolled.Theprogramconsistsofaseriesofpointlocationsatwhichoperationsareperformed.Suchasdrillingorpunchingahole..Chapter1INTRODUCTIONTON31.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.2.1TypesofNCMotionControlSystempoint-to-pointcontrolsystemManyNCpoint–to-pointsystemscontainamorecomplexMCU.INtheseservos,positioningcommandsareevaluatedsimultaneouslysothatvectormotionintwoaxesispossible.Themovementsbetweenpointscanbedonealongstraightor450vectorspathsdeterminedbythemachinewaysorslides.Suchsystemsaresometimescalledstraight-cutcontrolsystem.（点位/直线）.Chapter1INTRODUCTIONTON32.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.2.1TypesofNCMotionControlSystemContouringControlSystem

Itisalsocalledcontinuouspathcontrolsystem,whichmanagesthesimultaneousmotion(resultantmotion)ofthecuttingtoolintwo,three,four,offiveaxesbyinterpolating(插补)theproperpathbetweenprescribedpoints.Itenablesthecuttingtooltogenerateangularsurfaces,two-dimensionalcurves,orthree-dimensionalcontoursintheworkpiece,suchasmillingandturningoperations..Chapter1INTRODUCTIONTON33.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.2.1TypesofNCMotionControlSystemInterpolationTocutalongacircularpath,thecirclemustbedividedintoaseriesofstraight-linesegmentsthatapproximatethecircularpath.Thetooliscommandedtomachineeachlinesegmentinsuccessionsothatthemachinedsurfacecloselymatchesthedesiredshape..Chapter1INTRODUCTIONTON34.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.2.2TypesofNCServo-DriveSystem

TheprincipalfunctionofNCisthepositioningofthetoolorthemachinetableinaccordancewiththeprogrammeddata.IndustryhasdevelopedthreedifferenttypesofdrivesbasedonhowtheNCsystemaccomplishespositioning.Thesearetheopen-loop（开环）,theclosed-loop（闭环）andhalfclosed-loop（半闭环）drivesystem..Chapter1INTRODUCTIONTON35.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.2.2TypesofNCServo-DriveSystemOpen-LoopServo-DriveItisthesimplestandleastcostformofservo-drive.Itischaracterizedasasystemthatlacksfeedback.Thatis,onceaninputcontrolsignalissent,thereisnosensingdevicetoconfirmtheactionofthecontrolsignal.DrivingcircuitSteppingmotorWorktableLeadscrewPulsetrain.Chapter1INTRODUCTIONTON36.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.2.2TypesofNCServo-DriveSystemHalf-Closed-LoopServo-DriveItischaracterizedasasystemthattheindirectfeedbackmonitorstheoutputofservomotor.AlthoughthismethodispopularwithNCsystems,itisnotasaccurateasdirectfeedback,Thehalf-closed-loopsystemcomparesthecommandpositionsignalwiththedrivesignaloftheservomotor..Chapter1INTRODUCTIONTON37.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.2.2TypesofNCServo-DriveSystemHalf-Closed-LoopServo-DrivePositioncomparecircuitSpeedcontrolcircuitWorktableInstructionSpeedfeedbacksignalPositionfeedbacksignalLeadscrewServomotor.Chapter1INTRODUCTIONTON38.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.2.2TypesofNCServo-DriveSystemClosed-LoopServo-DriveItischaracterizedasasystemthatthedirectfeedbackmonitorstheoutputofservomotor.Afeedbacksensordirectlymeasuresthepositionofworktable.Withitsdrivesignaloriginatedbytheworktable,Itisthepreferredsystembecauseitmonitorstheactualpositionoftheworktableonwhichthepartismounted.Itismoreaccurate;however,itsimplementationcostsarehigher..Chapter1INTRODUCTIONTON39.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.2.2TypesofNCServo-DriveSystemClosed-LoopServo-DrivePositioncomparecircuitSpeedcontrolcircuitWorktableInstructionSpeedfeedbacksignalPositionfeedbacksignalLeadscrewServomotor.Chapter1INTRODUCTIONTON40.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.2.3ApplicationofCNCTheapplicationsofCNCaredividedintotwocategories:Machinetoolapplications;non-machinetoolapplications.

Itshouldbenotedthattheapplicationsarenotalwaysidentifiedbythename“numericalcontrol”,thistermisusedprincipallyinthemachinetoolindustry..Chapter1INTRODUCTIONTON41.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.2.3ApplicationofCNCMachineToolApplicationThemostcommonapplicationsofNCareinmachinetoolcontrol,machiningwasthefirstapplicationofNC.Machiningisamanufacturingprocessinwhichthegeometryofworkisproducedbyremovingexcessmaterial.Bycontrollingtherelativemotionbetweenacuttingtoolandtheworkpiece,thedesiredgeometryiscreated..Chapter1INTRODUCTIONTON42.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.2.3ApplicationofCNCMachineToolApplicationThecommonNCmachinetoolsarelistedinthefollowingalongwiththeirtypicalfeatures:NClathe(数控车床)Turningrequirestwo-axiscontinuouspathcontrol,eithertoproduceastraightcylindricalgeometryortocreateaprofile..Chapter1INTRODUCTIONTON43.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.2.3ApplicationofCNCMachineToolApplicationNCboringmill(数控镗铣床)horizontalorverticalspindle.Boringissimilartoturning,exceptthataninternalcylinderiscreatedinsteadofanexternalcylinder.Theoperationrequirescontinuouspath,two-axiscontrol...Chapter1INTRODUCTIONTON44.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.2.3ApplicationofCNCMachineToolApplicationNCdrillpress(数控钻床)Thesemachinesusepoint-to-pointcontrolofworkheadandtwoaxiscontroloftheworktable.SomeNCdrillpresseshaveturretscontainingsixoreightdrillbits..Chapter1INTRODUCTIONTON45.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.2.3ApplicationofCNCMachineToolApplicationNCmillingmachine(数控铣床)Itrequirescontinuouspathcontroltoperformstraightcutorcontouringoperations..Chapter1INTRODUCTIONTON46.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.2.3ApplicationofCNCMachineToolApplicationNCgrindingmachine(数控磨床)Itisintendedforfinishingtreatmentofworkparts.Thegrindingmachineincludescylindrical-,surface-,internal-,spindle-,thread-,gear-andtool-grindingmachines..Chapter1INTRODUCTIONTON47.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.2.3ApplicationofCNCMachineToolApplicationMachinecenter(加工中心)ItisdefinedasmultifunctionNCmachineswithautomatictoolchangerandtoolstorage.Ithastheabilitytoperformdrilling,turning,reaming,boring,milling,contouring,andthreadingoperationsonasinglemachine..Chapter1INTRODUCTIONTON48.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.2.3ApplicationofCNCMachineToolApplicationMachinecenter(加工中心)Machiningcentersareclassifiedaseitherverticalorhorizontal.Verticalmachiningcenterscontinuetobewidelyacceptedandused,primarilyforflatpartsandwherethree-axismachiningisrequiredonthesurfaceofasinglepartsuchasthemoldandthedie.Horizontalmachiningcentersareparticularlyusedforthelarge,boxy,andheavyparts..Chapter1INTRODUCTIONTON49.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.2.3ApplicationofCNCMachineToolApplicationMachinecenter(加工中心).Chapter1INTRODUCTIONTON50.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.2.3ApplicationofCNCNon-MachineToolApplicationPunchpressesforsheetmetalholepunching(数控冲床)Thetwo-axisNCoperationissimilartothatofadrillpressexceptthatholesareproducedbypunchingratherthanbydrilling..Chapter1INTRODUCTIONTON51.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.2.3ApplicationofCNCNon-MachineToolApplicationPressesforsheetmetalbending(数控折弯机)Insteadofcuttingsheetmetal,thesesystemsbendsheetmetalaccordingtoprogrammedcommands..Chapter1INTRODUCTIONTON52.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.2.3ApplicationofCNCNon-MachineToolApplicationWeldingmachine(数控焊接机)BothspotweldingandcontinuousarcweldingmachinesareavailablewithautomaticcontrolsbasedonNC..Chapter1INTRODUCTIONTON53.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.2.3ApplicationofCNCNon-MachineToolApplicationThermalcuttingmachine(数控热切割机)Suchasoxyfuelcutting(火焰切割),lasercutting(激光切割),andplasmaarccutting(等离子电弧切割).Thestockisusuallyflat;thustwo-axiscontrolisadequate.Somelasercuttingmachinescancutholesinpreformedsheetmetalstock,requiringfourorfiveaxiscontrol..Chapter1INTRODUCTIONTON54.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.2.3ApplicationofCNCNon-MachineToolApplicationTubebendingmachine(数控弯管机)Automatictubebendingmachinesareprogrammedtocontrolthelocationandtheangleofthebend.Importantapplicationsincludeframesofbicyclesandmotorcycles..Chapter1INTRODUCTIONTON55.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.3FEATURESOFNCANDITSAPPLICATIONAREAS1.3.1AdvantagesandDisadvantagesofNCNChasmanybenefitsandadvantagesovermanualproductionmethods,butNCismoresophisticatedtechnologythanconventionalproductionmethods..Chapter1INTRODUCTIONTON56.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.3.1AdvantagesandDisadvantagesofNCAdvantagesofNC(1)Greateraccuracyandrepeatability(2)Morecomplexpartgeometriesarepossible(3)Nonproductivetimeisreduced(4)Lowerscraprates(5)Inspectionrequirementsarereduced(6)Engineeringchangescanbeaccommodatedmoregracefully.Chapter1INTRODUCTIONTON57.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.3.1AdvantagesandDisadvantagesofNCAdvantagesofNC(7)Simplerfixturesareneeded(8)Shortermanufacturingleadtimes(9)Reducedpartsinventory(10)Lessfloorspacerequired(11)Operatorskill-levelrequirementsarereduced.Chapter1INTRODUCTIONTON58.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.3.1AdvantagesandDisadvantagesofNCDisadvantagesofNC(1)Higherinvestmentcost(2)Highermaintenanceeffort(3)Partprogram(4)HigherutilizationofNCequipment.Chapter1INTRODUCTIONTON59谢谢各位谢谢各位60数控技术概述课件61.Chapter1

INTRODUCTIONTONUMERICALCONTROL

1.1、FundamentalofNCTechnology1.2、ClassificationsofNCMachines1.3、FeaturesofNumericalControlandItsApplicationAreas.Chapter1INTRODUCTIONTON62CourseDescription:�NCisoneofthemostimportantachievementsinmechanicalengineeringfieldin20century.�Itisacrossingandintegratingtechnologycomprisingofcomputertechnology,automaticcontroltechnology,informationtechnology,sensetechnology,andmachiningtechnology.�NumericalControlTechnologyhasbecameoneoftheimportanttechnicalbasicclassesofmechanicalengineeringspecialty.CourseDescription:�NCisone63ToshibaeventsToshibaevents64.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.1、DevelopmentHistoryofNC

1946-thefirstcomputerappearedintheworld,whichliftthecurtainonthemankindintoinformationtime.

1948-ParsonsCorporationbroughtforwardusingcomputertocontrolmachinewhentheymachinedthesurfacecontoursofairfoilshape.ParsonsCorporationwasamini-helicoptermanufacturer.Themachiningaccuracyoftheairfoilshapewas±0.0381mm.Chapter1INTRODUCTIONTON65.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.1、DevelopmentHistoryofNC

UnderthesupportbytheU.SAirForceResponsedbytheServomechanismsLaboratoryattheMIT(MassachusettsInstituteofTechnology).Chapter1INTRODUCTIONTON66.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.1、DevelopmentHistoryofNC

Threeyearslater,in1952

MITandParsonsCorporationcooperatedwitheachother,anddevelopedthefirstNCmachinewhichnamedCincinnatiHydrotelmillingmachine.Background,timeandplace.Chapter1INTRODUCTIONTON67.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.1、DevelopmentHistoryofNCThefirstgeneration,1952~1955vacuumtubes,electricalrelaysandcomplicatedmachinecontrolinterfaces.Thesecondgeneration,1955~1959miniatureelectronictubes,transistors.Thethirdgeneration,1959~1965smallscaleintegratedcircuits..Chapter1INTRODUCTIONTON68.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.1、DevelopmentHistoryofNCAbovethreegenerations,

theirNCfunctionswereperformedbyhardware(electroniccircuits),sowecallthem“hardwiredNC”(硬线数控)

1955

1959

1965.Chapter1INTRODUCTIONTON69.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.1、DevelopmentHistoryofNCThefourthgeneration,1970s(1970~1974)minicomputers.(CNC)Thefifthgeneration,1974-microprocessor.1979(VLIC)(MCNC)1994~PC-NC..Chapter1INTRODUCTIONTON70.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.1、DevelopmentHistoryofNCAfterthefourthgenerations,

theirNCfunctionswereperformedbysoftware(basedoncomputer),sowecallthem“softwiredNC”or“computernumericalcontrol”(计算机数控CNC)

1970

1974

1994.Chapter1INTRODUCTIONTON71.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.2ConceptofNCandCNC1、NC(NumericalControl,数字控制)

NumericalControl（NC）isaformofprogrammableautomationinwhichthemechanicalactionsofamachinetoolorothermachinesarecontrolledbyaprogramcontainingcodedalphanumericdata..Chapter1INTRODUCTIONTON72.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.2ConceptofNCandCNC2、NumericalControlTechnology,(数控技术)

ItmeansthetechnologywhichadoptsNCmethodstocontrolaworkprocesstorealizetheautomation..Chapter1INTRODUCTIONTON73.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.2ConceptofNCandCNC3、NumericalControlMachineTools,(数控机床)

Itis

akindofmachinetools

whichadoptsthenumericalcontroltechnologytorealizetheworkprocessautomation.ItisatypicalexampleofNCapplication..Chapter1INTRODUCTIONTON74.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.2ConceptofNCandCNC4、NumericalControlSystem,(数控系统)

Itis

theequipmentwhichcanrealizethenumericalcontrol..Chapter1INTRODUCTIONTON75.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.2ConceptofNCandCNC5、CNC(ComputerNumericalControl,计算机数控)

Themachinecontrolunitsarebasedoncomputertechnology..Chapter1INTRODUCTIONTON76.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.3BasicComponentsofNCMachineTools

Thecontrolsystemofanumericallycontrolledmachinetoolcanhandlemanytaskscommonlydonebytheoperatorofaconventionalmachine.Thesystemhastheabilitytoperformthecontrolfunctionsthroughthenumericalinputinformation,whichisthecontrolprogram,alsocalledthepartprogram..Chapter1INTRODUCTIONTON77.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.3BasicComponentsofNCMachineToolsTheworkprocessofNCisshownastherightfigure.PartdrawingPartprogramControlcomputerServo-driveunitMachinetoolPartFirstly,thepartprogrammershouldstudythepartdrawingandtheprocesschart..Chapter1INTRODUCTIONTON78.Chapter1

INTRODUCTIONTONUMERICALCONTROL1.1.3BasicComponentsofNCMachineToolsTheworkprocessofNCisshownintherightfigure.PartdrawingPartprogramControlcomputerServo-driveunitMachinetoolPartThenthepartprogrammershouldpreparethecontrolprogramonastandardforminthespecifiedfo