数控技术双语课件.ppt

领域：领域：领域：领域：数控技术、数控技术、数控技术、数控技术、CAD/CAMCAD/CAMCAD/CAMCAD/CAM技术、柔性加工技术、集成制造技术、柔性加工技术、集成制造技术、柔性加工技术、集成制造技术、柔性加工技术、集成制造 技术、智能制造技术、虚拟制造技术、绿色制造技术技术、智能制造技术、虚拟制造技术、绿色制造技术技术、智能制造技术、虚拟制造技术、绿色制造技术技术、智能制造技术、虚拟制造技术、绿色制造技术趋势：趋势：趋势：趋势：高精度、高效率、自动化、信息化、智能化高精度、高效率、自动化、信息化、智能化高精度、高效率、自动化、信息化、智能化高精度、高效率、自动化、信息化、智能化 制造业数控化率年增长率达制造业数控化率年增长率达制造业数控化率年增长率达制造业数控化率年增长率达6%6%6%6%，据预测到，据预测到，据预测到，据预测到2020202020202020年，年，年，年，我国制造业数控化率将达到我国制造业数控化率将达到我国制造业数控化率将达到我国制造业数控化率将达到60%60%60%60%，正向制造业大国迈进。，正向制造业大国迈进。，正向制造业大国迈进。，正向制造业大国迈进。NUMERICAL CONTROL TECHNOLOGYChapter 2 NC Part Programming Electromechanical Engineering CollegeElectromechanical Engineering CollegeHenan University of Science and TechnologyHenan University of Science and Technology _.Chapter2 NC PART PROGRAMMING2.1、Introduction to NC part programming2.2、The codes used in CNC2.3、Manual part programming2.4、Automatic programming_.Chapter2 NC PART PROGRAMMING2.1、Introduction to NC part programmingTheprogramofinstructionsisthedetailedstep-by-stepcommandsthatdirecttheactionsoftheprocessingequipment.Inmachinetoolapplications,theprogramofinstructionsiscalledapartprogram,andthepersonwhopreparestheprogramiscalledapartprogrammer.Numericalcontrol(NC)isaformofautomaticallyoperatingamachinetoolbasedoncodedalphanumericdata.Acompletesetofcodedinstructionsforexecutinganoperationiscalledaprogram.Theprogramistranslatedintocorrespondingelectricalsignalsforinputtoservomotorsthatrunthemachine._.Chapter2 NC PART PROGRAMMING1、Introduction to NC part programmingwecallthewholeprocessfrompartgraphicstofinishingcontrolmediumtheprogrammingofnumericalcontrolmanufacturing,orcallitNCprogramming.Whenusingnumericalcontrolmachinetooltomanufactureparts,theprogrammingisveryimportant.Theprogramisnotonlycorrectandfastbutalsoeffectiveandeconomic_.Chapter2 NC PART PROGRAMMING2.1.1The contents and steps of numerical control programmingTheprogramcanbeinputtedintoCNCsystemandtheCNCsystemcontrolsCNCmachinetoolstomanufactureautomatically.Generallyspeaking,themainstepsofNCprogrammingareanalyzingpartgraphics,determiningthemanufacturingtechnologicalprocess,calculatingnumericalvalue,programming,verifyingtheprogramandinputtingtheprogramintoCNCsystem.Figure2.1illustratestheprogrammingsteps._.Chapter2 NC PART PROGRAMMING2.1.1The contents and steps of numerical control programmingBeforeNCprogramming,theprogrammershouldunderstandthenumericalcontrolmachinespecifications,characteristics,thefunctionsandprogramminginstructionsformatoftheCNCsystem,etc.Whenprogramming,heshouldanalyzethepartstechnicalrequirements,geometricalshape,dimensionsandtechnologicalrequirements.Thenhecandeterminethemanufacturingmethodandcalculatenumericalvalue,getcutterposition.Accordingtopartdimension,cutterpositionvalue,cuttingparameters(spindlespeed,feed-rate,cuttingdepth)andauxiliaryfunctions(ATC,CW,CCW,coolantonandoff),theprogrammercanprogram._.Chapter2 NC PART PROGRAMMING2.1.1The contents and steps of numerical control programming(1)Analyzingpartgraphicsanddeterminingthemanufacturingtechnologicalprocess(2)Thisstepincludesanalyzingthepartgraphics,understandingthemachiningcontentsandrequirements.Thendeterminingtechnologicalprocesses,machiningplans,machiningsequence,machiningroutes,fixingmethods.Cuttingparametersandselectingcuttingtools,etc.Besidesthese,thenumericalcontrolmachinecodesshouldbeunderstoodclearlyandthenumericalcontrolmachinefunctionsshouldbeexploitedfully._.Chapter2 NC PART PROGRAMMING2.1.1The contents and steps of numerical control programmingFigure2.1 ThestepsofNCprogramming_.Chapter2 NC PART PROGRAMMING2.1.1The contents and steps of numerical control programming(2)CorrectlyselectingprogramoriginandcoordinatesystemInnumericalcontrolmachinetoolsmanufacturing,correctlyselectingprogramoriginandcoordinatesystemisveryimportant.OnNCprogramming,theprogramcoordinatesystemisthestandardcoordinatesystemascertainedontheworkpiece._.Chapter2 NC PART PROGRAMMING2.1.1The contents and steps of numerical control programming(3)CalculatingnumericalvaluesAfterfinishingthetechnologicalprocess,thenextstepistogetthetoolpathaccordingtopartgeometricdimensionandthemethodofcutterradiuscompensation,sowewillobtainthecutterposition._.Chapter2 NC PART PROGRAMMING2.1.1The contents and steps of numerical control programming(4)WritingpartprogramsAfterdeterminingmachiningroute,technologicalprocessandthecoordinatevalueoftoolpath,step-by-step,theprogrammercanwritetheprograminaccordancewiththespecifiedfunctioncodesandprogramformatofCNCsystem._.Chapter2 NC PART PROGRAMMING2.1.1The contents and steps of numerical control programming(5)FabricationcontrolmediumTheprogramiscodedonasuitablemediumforsubmissiontothemachinecontrolunit.Formanyyears,thecommonmediumwas1-inchwidepunchedtape,usingastandardformatthatcouldbeinterpretedbythemachinecontrolunit.Today,punchedtapehaslargelybeenreplacedbynewerstoragetechnologiesinmodernshops.Thesetechnologiesincludemagnetictape,diskette,andelectronictransferofpartprogramsformacomputer._.Chapter2 NC PART PROGRAMMING2.1.1The contents and steps of numerical control programming(6)VerifyingpartprogramsBeforetheprogramisusedinrealproduction,wemustchecktheprogram.wedetecttoolpatherrorsthatcouldruinthepart,damagethefixtures,breakthecuttingtoolorcrashthemachine,etc.Insomecases,wetesttheprogramthroughmanufacturingapartonamachine.Onthebasisofdetectingresult,theprogramisneededtobemodifiedandtobeadjusted,untiltheprogramsatisfiesthemachiningrequirementscompletely._.Chapter2 NC PART PROGRAMMING2.1.1The contents and steps of numerical control programmingThestepsabovementionedareprogrammedmanually.Thisprogrammingmethodiscalledmanualpartprogramming.Andwealsoknowthataprogrammernotonlymusthavetheknowledgeofthestructureofmachinetools,thefunctionsandstandardsofCNCsystem,butalsohavetheknowledgeoftechnologicalprocess,suchasfixtures,cuttingtoolsandcuttingparameters,etc._.Chapter2 NC PART PROGRAMMING2.1.2The Methods of NC ProgrammingPartprogrammingcanbeaccomplishedusingavarietyofproceduresrangingfrommanualmethodtohighlyautomatedmethod.(1).Manualpartprogramming(2).Automaticprogramming_.Chapter2 NC PART PROGRAMMING2.1.2The Methods of NC Programming(1).ManualpartprogrammingTheprogrammingiscalledmanualpartprogrammingwhichwholepartprogrammingiscompletedmanually(includingcalculatingnumericalvalueonacomputer).Inmanymechanicalmanufacturingtrades,therearealargenumberofuncomplicatedpartsthatareconstitutedonlybythesimplegeometricelementsofstraightlinesandcircles.thenumericalvaluesofthepartsarecalculatedsimply._.Chapter2 NC PART PROGRAMMING2.1.2The Methods of NC Programming(1).ManualpartprogrammingTheblocksofaprogramarentlot.Andcheckingtheprogramiseasy.Thesepartprogramscanbecompletedmanually.Somanualprogrammingisstillaverycommonprogrammingmethodathomeandabroad.Butmanualprogramminghasdifficultyorimpossibilitygoprogramcomplicatedpartsthathavenon-circularcurvesandsurfaces.Sowemustusetheautomaticpartprogrammingtoprogram._.Chapter2 NC PART PROGRAMMING2.1.2The Methods of NC Programming(1).AutomaticprogrammingAutomaticprogrammingisalsocalledcomputer-aidedprogramming.Mostoralloftheprogrammingiscompletedbyacomputer,suchascalculatingnumericalvalues,writingprograms,fabricatingthecontrolmedium,etc.Automaticprogramminglightensprogrammerintensityoflabor,shortenstheprogrammingtimeandimprovestheprogrammingquality._.Chapter2 NC PART PROGRAMMING2.1.2The Methods of NC Programming(1).AutomaticprogrammingAtthesametime,itsolvesthecomplicatedpartprogrammingwhichisimpossibletoprogrambymanualprogramming.Themorepartsarecomplicatedshapeandtechnologicalprocess,themoresuperiorityofautomaticprogrammingclearis._.Chapter2 NC PART PROGRAMMING2.1.2The Methods of NC Programming(1).AutomaticprogrammingTherearemanymethodsofautomaticpartprogramming.Accordingtothedifferencesofinputprogrammingmessageandhandlingstylesbyacomputer,theyaredividedintoautomaticallyprogrammedtool(APT)basedonautomaticprogramminglanguageandpartprogrammingusingCAD/CAMbasedoninteractivegraphicssystem.ACAD/CAMsystemisacomputerinteractivegraphicssystemequippedwithsoftwaretoaccomplishcertaintasksindesignandmanufacturing._.Chapter2 NC PART PROGRAMMING2.1.3The Basis of NC Part Programming2.1.3.1.TheGeometricBasisofNCPartProgrammingThelocationofaCNCmachinetoolsatanytimeiscontrolledbyasystemofXYZcoordinatescalledCartesiancoordinates.Thissystemiscomposedofthreedirectionallines,calledaxes,mutuallyintersectingatanangleof900.Thepointofintersectionisknownastheorigin.(1).NCCoordinateSystems_.Chapter2 NC PART PROGRAMMING2.1.3The Basis of NC Part Programming2.1.3.1.TheGeometricBasisofNCPartProgramming(1).NCCoordinateSystems Primary machine axes of movement should follow the right-hand rule.See left figure.Spindle movement is primarily along the Z axis.movement into the workpiece is along the Z axis and movement away from is along the+Z axis._.Chapter2 NC PART PROGRAMMING2.1.3The Basis of NC Part Programming2.1.3.1.TheGeometricBasisofNCPartProgramming(1).NCCoordinateSystems In a majority of milling machines,motion along the X axis is the longest travel perpendicular to Z.the X axis is parallel to the work holding and is in the horizontal plane.The+X axis moves to the right along a plane of the work as the operator looks at that plane.spindleworktable_.Chapter2 NC PART PROGRAMMING2.1.3The Basis of NC Part Programming2.1.3.1.TheGeometricBasisofNCPartProgramming(1).NCCoordinateSystems With regard to milling machines,motion along the Y axis is the shortest travel perpendicular to Z,the Y axis is in the same plane as the X axis.Looking at the plane,the operator will note that the Y is perpendicular to the X axis.spindleworktable_.Chapter2 NC PART PROGRAMMING2.1.3The Basis of NC Part Programming2.1.3.1.TheGeometricBasisofNCPartProgramming(1).NCCoordinateSystems Most CNC milling machines can perform simultaneous motions along the X,Y and Z axes and are called three-axis machines.See left figure._.Chapter2 NC PART PROGRAMMING2.1.3The Basis of NC Part Programming2.1.3.1.TheGeometricBasisofNCPartProgramming(1).NCCoordinateSystems More complex CNC machines have the capability of executing additional rotary motions as follows:vRotation about an axis parallel to the X axis or A-axis rotationvRotation about an axis parallel to the Y axis or B-axis rotation.vRotation about an axis parallel to the Z axis or C-axis rotation_.Chapter2 NC PART PROGRAMMING2.1.3The Basis of NC Part Programming2.1.3.1.TheGeometricBasisofNCPartProgramming(1).NCCoordinateSystems Rotary motion directions also follow the right-hand rule.See right figure.、_.Chapter2 NC PART PROGRAMMING2.1.3The Basis of NC Part Programming2.1.3.1.TheGeometricBasisofNCPartProgramming(2).Programzeropoint_.Chapter2 NC PART PROGRAMMING2.1.3The Basis of NC Part Programming2.1.3.1.TheGeometricBasisofNCPartProgramming(3).Typesoftoolpositioningmodes_.Chapter2 NC PART PROGRAMMING2.1.3The Basis of NC Part Programming2.1.3.2.TheTechnologicalBasisofNCProgramming(1).Determiningthepartmachiningroutesrationally_.Chapter2 NC PART PROGRAMMING2.1.3The Basis of NC Part Programming2.1.3.2.TheTechnologicalBasisofNCProgramming(2).SelectingtoolsettingpointandtoolchangingpointrationallyvThe setting point makes operating easily and programming simply;vThe point is easy to find;vThe caused machining error is small._.Chapter2 NC PART PROGRAMMING2.1.3The Basis of NC Part Programming2.1.3.2.TheTechnologicalBasisofNCProgramming(2).SelectingtoolsettingpointandtoolchangingpointrationallyboringboringtooltooldrilldrillendmillendmillfacetoolfacetoolfiguretoolfiguretoolballnoseballnoseendmillendmillTurningtoolTurningtool_.Chapter2 NC PART PROGRAMMING2.1.3The Basis of NC Part Programming2.1.3.2.TheTechnologicalBasisofNCProgramming(3).Rationallyselectingthemethodsoffixing,cuttingtoolsandcuttingparametersvSelecting standard and common fixtures as far as possible,avoiding selecting special fixtures;vFixing and removing parts quickly,conveniently and rationally;vThe part surface to be machined should be exposed to outside.Dont let the fixture affect the rapid motion and machining of a tool._.Chapter2 NC PART PROGRAMMING2.2、THE CODES USED IN CNC Therearemanycodesincludedinaprogram.PreparatoryfunctionsareGcodesandauxiliaryfunctionsareMcodes.TheyarethebaseofCNCprograms.ISOhasworkedoutthestandardsofGcodesandMcodes.BecausenewCNCsystemsandmachineshavebeenemerging,alotoffunctionsinmanysystemssurpassISOstandards.Theircodesareabundantandtheirformatsareflexible.TheyarentrestrainedbyISOstandards._.Chapter2 NC PART PROGRAMMING2.2、THE CODES USED IN CNC Inaddition,evenifthesamefunction,itscodeandformathavealotofdifferencesamongsystemsmadeindifferentcompanies.Andcodesandformatsalsohavedifferencesbetweennewandoldsystemsmadeinthesamecompany.ButthepreparatoryfunctionscodesandauxiliaryfunctionscodesinmostofCNCsystemsareuptoorsimilartotheISOstandards.BeforeintroducingtheGcodesandMcodes,wemustunderstandprogramminglangueformatsfirst._.Chapter2 NC PART PROGRAMMING2.2.1 ProgrammingLanguageFormatAprogramformatisasystemofarranginginformationsothatitissuitableforinputtoACNCcontroller.Severaldifferenttypesofformatsexist.Theformattobeusedinthistextisknownasthewordaddress.(1)AddressesAnaddressisaletterthatdescribesthemeaningofthenumericalvaluefollowingtheaddress._.Chapter2 NC PART PROGRAMMING2.2.1 ProgrammingLanguageFormat(2)WordsWordsareusedtodescribesuchimportantinformation.asmachinemotionanddimensionsintheblock.Programwordsarecomposedoftwomainparts:anaddressfollowedbyanumber.TheFigure2.9illustratestheaddress,numberandwords.G17 Address NumberY-35.68 Address NumberWords _.Chapter2 NC PART PROGRAMMING2.2.1 ProgrammingLanguageFormat(3)BlocksAblockisacompletelineofinformationtotheCNCmachine.Itiscomposedofonewordoranarrangementofwords.Blocksmayvaryinlength.Thus,theprogrammerneedsthosewordsinablocktoexecuteaparticularmachiningfunction.“N10 G01X-63.75Y70.28F100.S1000M03;”.Eachblock is separated from the next by an end of-block(;)code._.Chapter2 NC PART PROGRAMMING2.2.1 ProgrammingLanguageFormat(3)BlocksTheend-of-blockcharacterisautomaticallygeneratedwhentheprogrammerpressesreturnkeyatthecomputer.Thesameholdstruewhentheend-of-blockkeyispressedatthemachinepanelboardduringmanualdateentry.Thus,thischaracterwillnotappearintheregularprogramlistingsinthistext._.Chapter2 NC PART PROGRAMMING2.2.1 ProgrammingLanguageFormat(4)ProgramsAprogramisasequenceofblocksthatdescribeindetailthemotionsaCNCmachineistoexecuteinordertomanufactureapart.TheMCUexecutesaprogramblockbyblock.Theorderinwhichtheblocksappearistheorderinwhichtheyareprocessed.Table2.1illustratestheformatandtheorderinwhichtheMCUexecutesaprogram.Theorderinwhichaddressesappearinablockcanvary._.Chapter2 NC PART PROGRAMMING2.2.1 ProgrammingLanguageFormat(5)Programandsequencenumbers(O,Ncodes)(i)ProgramNumber(O)ProgramsarestoredintheMCUmemorybyprogramnumber.Themachinerecognizesprogramsaccordingtoanumericcode.Mostmachinescanstoreseveralprogramsatatime.ProgramnumbersrangefromO0000toO9999._.Chapter2 NC PART PROGRAMMING2.2.1 ProgrammingLanguageFormat(5)Programandsequencenumbers(O,Ncodes)(ii)SequenceNumber(N)Asequencenumberisanoptionaltagthatcanbecodedatthebeginningofablockifneeded.