机械制造类专业英语 课件汇 模块1-4 Basics in Mechanical Workplace - Die ＆ Mold Tec

ModuleIMasteringbasicsinWorkshopSceneOne

HealthandSafetyinWorkshopPhysical(e.g.plant/machine,noise,electrical,lighting,radiation,workingatheights,housekeeping)Chemical(e.g.hazardoussubstances,dangerousgoods)Ergonomic(e.g.manualhandling)Psychological(e.g.workstressors)BiologicalSafetyissueOKNot

OKPlantoimprove?Wideenoughforgoodstraffic.Adequately

lit.Surfacefreefromdefects.Clearofcases,materialsandrubbish.Engineeringcontrolsmayincludechangingprocesses,equipmentortools,forexample:installationofmachineguardsandmachineoperationcontrolsventilationtoremovechemicalfumesanddusts,andusingwettingdowntechniquestominimizedustlevelschanginglayoutofworklevelstominimizebendingandtwistingduringmanualhandlingpromoteasafeenvironmentpreservelifepreventinjuryorillnessfrombecomingworsehelppromoterecoveryprotecttheunconsciousreassuretheillorinjuredbasicfirstaidnotesindividuallywrappedsterileadhesivedressingssterileeyepadssterilecoveringsforseriouswoundstriangularbandagessafetypinsworkbenchordressingtrolleycupboardsforstorageofmedicalsupplies,dressingsandlinensoileddressingcontainerselectricalpowerpointsmedicalexaminationcouchwithblanketsandpillowschemicalspillsorchemicalreleasebombthreatsstructuralfaultsinthebuildingfloodingorseverewaterdamagethreatsofviolenceorrobberySmokingonlywherepermitted.Large,non-tipashtraysshouldbeusedandeverythinginthemshouldbecoldbeforetheyareemptied.Keepingpassagewaysandexitsfreefromstorageandwasteinordertominimizecombustiblematerial.1.Eliminateorreplacetheplantoritsoperationwithaquieteroperation.2.Replacenoisyequipmentwithnewerequipmentthatcreateslessnoise.3.Usesoundabsorbingmaterialtoabsorbvibrationandthusreducenoise.4.Enclosenoisymachineryorputbarriersbetweenthemachineryandpeople.5.Reducetheamountoftimepeopleareexposedtonoise,oruseearmuffsSceneTwo

WorkplaceToolsandMeasuringEquipmentchisel鉴子Application:cuttingrivetsboltsnutsandsheetsteel.diamond-point钻石刻刀Application:cleaningkeywaysthreadsandcorners.die板牙socketaccessories(bracespeed)手摇驱动器

Application:Unscrewingloosebolts.Screwingboltsornutsuntiltheyarejusttight.

extension加长杆Application:Locatingthehandleorspeedbraceinapositionthatclearsothercomponentsorbodywork.slidingtee滑动板手Application:AsaboveratchetApplication:Unscrewingboltsornutswhenspacearoundthemislimited.universaljoint万向节extradeep加深型Application:Looseningortighteningcomponentsornutsfittedsomedistancefromtheendoftheirstuds.sparkplug火花塞套筒板手Application:Looseningortighteningsparkplugs.

impact冲去套筒ring双梅花板手Application:Looseningortighteningboltsornutsthathaveconfinedspaceabovethem.combination两用板手Application:Hastheadvantagesofbothtypesofspanners.tap(hand)丝锥wrench(adjustable)活动板手Application:Substitutingforthecorrectspanner.pipe管子钳Application:Grippingandturningcylindricalshapes.Handtools---specializedgrease(hand)润

oilgun(hand)手动油枪Application:Withdrawingoilfromacomponentorinsertingoilintoacomponent.pipecutter管子切割器Application:Cuttingtheendofsteelorcoppertubingsothatitissquare.Application:Removingoilseals.steeringwheel转向盘拉拔器Application:Removingsteeringwheels.

valvetapper气门研磨具Whenusingalltoolsandequipment,thesafetyaspectisextremelyimportant.Toolsandequipmentusedforthepurposeforwhichtheywereintendedwillnotbearisktotheoperator,hisorherworkmatesorthecomponentpartsorthevehicle.Itistheresponsibilityoftheoperatorandtheworkshopmanagertoserviceandmaintainalltoolsandequipment.coolingsystem水温检测仪

Application:Testingacoolingsystemforleaks.Testingaradiatorcappressuresetting.compressiongauge压力表feelergauge塞尺Application:Measuringsmallclearancesorgapsthatexistbetweentwocomponents.Forexampleusedtomeasuretappetclearance.

insidecaliper内卡钳

pressureandcacuumgauge真空压力表Application:Testingthepressureandcacuumofamechanicalfuelpump.Testingtheinletmanifoldvacuumofarunningengine.sparking-pluggauge火花塞规Application:Settingthetensionofboltsornutstoagivenvalue.veeblockV形块Application:Testingtheresistanceofanelectricalcomponentthathasbeendisconnectedorremovedfromitscircuit.multi-meter万用表Application:Testingamps,ohmsandvoltsrelatedtothecomponentsinagivenelectricalcircuit.

timinglight正时检测仪Becauseaccuratemeasurementisoftenessential,itisnecessarytolearntousethevariousmeasuringtoolsefficiently.Thesimplesttoolformeasuringisthegraduatedrulewhich,forautomotivework,ismadeofalloysteel,hardenedandground.Thethreeformsofelectricalcircuitsarethe1.Series2.Parallel3.Acombinationofboth,knownasseries/parallel.UnitFiveAppliedWriting

Part1NoticeofInvitationforBids招标通告通常由以下几部分组成:标题(Headline)招标单位名称(NameofTenderingUnit)工程名称(NameoftheProject)工程招标号(BidofNumber)正文(BodyCopy)附项(SupplementaryItems)Part2ProductSpecification产品说明书是帮助用户认识产品，指导用户使用产品的书面材料。机械产品说明书的内容一般包括产品特点、用途、规格、结构、性能、操作程序及注意事项等。产品说明书大多都由标题、正文、落款三部分组成。产品说明书的文体特点为简略性、技术性、描述性和客观性。Part2ProductSpecification简略性表现为内容简略，文字浅显，句式简单，大量使用祈使句和省略句，避免使用不必要的修辞手段。技术性指说明书中文字涉及某方面的专业知识。描述性表现为文字具有层次感、程序性和说服力。客观性是指用在说明书中的词语应该恰当、如实地反映产品的真实情况。Part3ReadingSkillsofScientificandTechnicalEnglish

科技英语文章的阅读有以下五个方面的技巧:获取主题思想(ReadingforMainIdea)

获取主题思想的阅读技巧分四步：

(1)辨认主题名词；

(2)找出主题句；

(3)获取主题思想；

(4)避免不相关的内容。获取细节(ReadingforDetails)Part3ReadingSkillsofScientificandTechnicalEnglish理解词义(UnderstandingVocabulary)(1)通过上下文线索猜测词义

(2)通过构词法掌握词汇前缀、后缀和词根

(3)扩大知识面，克服背景知识方面的障碍Part3ReadingSkillsofScientificandTechnicalEnglish理解句子(UnderstandingSentence)(1)分析句子

(2)利用标点符号

(3)利用参照词

(4)利用信号词Part3ReadingSkillsofScientificandTechnicalEnglish抓住段落核心，整体理解文章(UnderstandingArticle)(1)研读(studyreading)(2)略读（skimming）

(3)浏览（scanning）Part4HowtoWriteaScientificPaper

Engineeringmaterialsfallintotwobasictypes:metallicornon-metallic.Non-metallicmaterialsarefurtherclassifiedasorganicorinorganicsubstances.Inmetalworking,ironisthemostimportantnaturalelement.Whencombinedwithotherelementsintovariousalloysitbecomestheleadingengineeringmetal.Thenonferrousmetals,includingcopper,tin,zinc,nickel,magnesium,aluminium,lead,andothersallplayanimportantpartinouteconomy.

SceneOneMechanicalMaterials

√copper√zinc√tin√nickel√magnesium√aluminium√leadtheitemswhichbelongtononferrousmetals

SceneOneMechanicalMaterials

Engineeringpropertiesincludetensilestrength,compressivestrength,torsionstrengthandmagneticproperties.（x）Thepropertiesofmaterialsincludedensity,vaporpressureandelectricproperties.（√）Pullingonthetwoendsofaspecimencandeterminetensilestrength.（√）Therearestandardtestsfordeterminingshearortorsioncharacteristics.（x）Theshearstrengthofamaterialisgenerallyabout75%ofitstensilestrength.（x）Strengthincompressionisvalidforductilematerials.（x）SceneOneMechanicalMaterials

Ductilematerials朔性材料Heattreatment热处理compressivestrength抗压强度torsionalstrength抗扭强度tensilestrength抗拉强度dissolve溶解SceneOneMechanicalMaterials

Lowcarbonsteelcontaining0.05%and0.3%carbonMediumcarbonsteelcontaining0.3%and0.7%carbonHighcarbonsteelcontaining0.7%and1.5%carbonSceneOneMechanicalMaterials

Asthecarboncontentisincreasedincarbonsteel,thestrength,toughness,andhardnessalsoincreasewhenthemetalisheatedtreated.SceneOneMechanicalMaterials

Alloysteelscontainthesamecontentascarbonsteels.T 2.Alloysteelscontainelementssuchaschromium,molybdenumandvanadium.T 3.Theessentialconstituentsinbothcarbonandalloysteelsareferriteandcarbon.T SceneOneMechanicalMaterials

Alloysteelscontainthesamecontentascarbonsteels.T 2.Alloysteelscontainelementssuchaschromium,molybdenumandvanadium.T 3.Theessentialconstituentsinbothcarbonandalloysteelsareferriteandcarbon.T SceneOneMechanicalMaterials

1.highcompressivestrengthexpectedevenathightemperatures2.wearresistance3.greattoughness4.corrosionresistanceandgoodthermalconductivityThemostimportantrequirementsforthemoldsteelsare

SceneOneMechanicalMaterials

thefollowingcanbeusedforfillerofplastics

（√）woodflour（√）cottonfrock（√）cottonlinters（√）cottoncloth（√）asbestosfiber（√）mica（√）glassfibers

（√）silicon（√）cellulose（√）claySceneOneMechanicalMaterials

SceneTwoElectricalmachining

Mostelectricalmachiningprocesseshavecomeaboutduetothedevelopmentofapace-agemetalalloysthataretoughandhardtomachine.Grindingcutting,andshapingwithcuttingtoolsareexacting,time-consuming,andexpensiveprocessesonsuchalloys.

SceneTwoElectricalmachiningMostelectricalmachiningprocesseshavecomeabout__________thedevelopmentofapace-agemetalalloysthatare____________and________________tomachine.Grindingcutting,andshapingwithcuttingtoolsareexacting,_______________,andexpensiveprocessesonsuchalloys.Insomecases,machiningwithconventionalequipmentisalmostimpossible.

SceneTwoElectricalmachiningOnstandardmachinetools,electricalenergyisconvertedbyanelectricmotorintomotionthatistransmittedthroughaseriesofshafts,pulleys,belts,andgearstoacuttingtool.Incontrast,theelectricalmachiningprocessesmakedirectuseofelectricalenergy.

SceneTwoElectricalmachiningWorkwithyourworkmatesreadingtheabovematerialcarefullyandthentrytounderstandthekindsofprocessesofelectricalmachining.Pleasecooperatewithyourpartnersandwritedownyouranswers

SceneOne latheDrillingn.钻削Millingn.铳削Fastenv.固定，加固，连接Feedn.进给，送给Cuttern.刀具Clampn.夹子Carriagevt.溜板Bedn床Headstockn.主轴箱Tailstockn.尾架Slidev.滑动SceneOne latheThelargestpartofthelatheiscalledthebedonwhichtheheadstockandthetailstockarefastenedatoppositeends.Ontheupperpartofthebedtherearespecialwaysuponwhichthecarriageandthetailstockslide.SceneOne lathelatheroundworkaxisturningtheworkparalleltotheaxisangletothisaxiscutterfeedclampedtoolpostcarriagelathehandSceneOne lathe

Thealignmentofthelathecentersmaybetestedbytakingacutandthenmeasuringbothendsofthecutwithamicrometer.Notallworksshouldbefastenedbetweenthetwocentersofthelathe.Ashortworkmaybeturnedwithoutusingthedeadcenter,bysimplychuckingitproperlyatthespindleoftheheadstock.SceneOne lathelathechuckclampingwobblingturningthechuckheadstockspindleconstructiongearboxshortworkthree-jawuniversalchuckfour-jawchucklathecenterdeadcenterSceneTwoMilling

Removev旋转Mountv固定Arborn心轴Spacern垫片Bushingn村套Yoken刀杆支架Slitv切开Clockwiseadj

顺时针Regularadj

规则的

particularadj

特别的Horizontaladj

水平的Variousadj

不同点Variationn变化SceneTwoMilling

Regularorirregularshapedworkmaybeproducedonamillingmachine.Designsvaryingaccordingtotheparticularclassofworkwanted.Accordingtothepositionofthespindle,themillingmachinesmaybedividedintotwogroupsofverticalspindlemillingmachinesandhorizontalspindlemillingmachines.Millingmachinesmaybeintovariousclasses.SceneTwoMilling

cylindricalcutters（）

endmillingcutters（）sideandfacecutters（）formmillingcutters（）angularcutters（）slittingsaw（）SceneTwoMilling

Accordingtothe__________ofthespindle,themillingmachinesmaybedividedinto__________groupsofverticalspindlemillingmachinesand__________spindlemillingmachines.Millingmachinesmaybegroupedintovarious__________.SceneTwoMilling

Thedividinghead(alsocalledanindexhead)isadeviceusedtodividetheperipheryofapieceworkintoanynumberofequalparts,andtoholdtheworkintherequiredpositionwhilethecutsarebeingmade.Variouskindsofvisesmaybeusedforholdingtheworkinamillingmachine,themostcommonbeingtheplainvise,andtheswivelvise.SceneTwoMilling

Variousattachmentsareusedforincreasingthe__________ofworkthatcanbeperformedona__________machine.Thedividinghead(alsocalledan__________)isadeviceusedtodividetheperipheryofapieceworkintoanynumberof__________parts,andtoholdtheworkinthe__________positionwhilethecutsarebeingmade.Variouskindsof__________maybeusedforholdingtheworkinamillingmachine,themostcommonbeingthe__________vise,andSceneSixGrindingmachines

Conicaladj

圆锥的Surplusn过剩Exterioradj

外面的Tapern锥形Sharpenvt

使锐利Substiuten代替者Basen床身Concentricityn同轴度Peripheryn圆柱表面Infeedn横向进给Interioradj内部的SceneSixGrindingmachines

1.Cylindricalgrinding.Exteriorcylindersandtapersaregroundonplaingrindingmachinesandoncenterlessgrinders.Theconstructionofuniversalgrindingmachinesissimilartothatofplaingrinders.Theyareequippedwithaninternalgrindingattachment,however,nothattheycandobothcylindricalandinternalgrinding.2.Internalgrinding.Interiorcylindersandtapersaregroundoninternalgrindingmachinesandoncenterlessgrinders..SceneSixGrindingmachines

Agrinding_____________isamachinewhichemploysagrinding_____________forproducingcylindrical,conicalorplane_____________accuratelyandeconomicallyandtothe_____________shape,size,andfinish.Thesurplusstockisremovedbyfeedingtheworkagainsttherevolvingwheelorbyforcingtherevolvingwheel_____________thework.SceneSixGrindingmachines

Intraverse-cutgrinding,thework-pieceisfedlongitudinallypastthefaceofthegrindingwheel,andthewheelisfedtowardtheworkaftereachreversalofthetableuntilthepieceisfinishedtosize.Theinfeedateachreversalshouldbefrom0.001to0.005inchforroughing,andfrom0.0005to0.0025inchforfinishing.inplunge-cutgrinding,agrindingwheelthathasafacewidthSceneSixGrindingmachines

Grinder磨床Capable有能力的Swivel旋转Degree程度Line线Footstock尾架Dog挡块Rapid迅速的,快的Rapidly快,迅速地Rate率,比率,速度Oppositely在对面,相反的SceneSixGrindingmachines

Boththegrindingwheelandthework-piecerotateduringthemachiningoperations.Thegrindingwheelturnsrapidly-825to1,250rpm.Theworkpieceturnsamuchslowerrate-100to400rpm.Thesurfacesofthegrindingwheelandtheworkpiecemoveinoppositedirectionsattheirlineofcontact.Thetableisusedtomovethework-pieceacrossthefrontofthewheel.SceneSevenRadialdrillingmachines

Radialadj

半径的Radiallyadv沿径向Handlen把手Armn臂Circlen圆Controln控制Selectvt

选择Selectorn选择器Levern杠杆SceneSevenRadialdrillingmachines

Spindlefeedsandspeedsarecontrolledbyselectorleverswhichengagethepropergearsinthedrillhead.Depthoffeedisalsocontrolleddirectlyinthedrillheadbyasuitablemechanism.Inadditiontodrills,othertoolssuchasreamersandboringSceneSevenRadialdrillingmachines

Spindlefeedsandspeedsarecontrolledbyselector___________whichengagethepropergearsinthedrillhead.Depthof___________isalsocontrolleddirectlyinthedrillheadbya___________mechanism.Inadditiontodrills,othertoolssuchas___________and___________canalsobeused;thesetoolsaddagreatdealof___________tothismachine.SessionOneCNCMachineAcomputernumericalcontrol(CNC)machineisanNCmachinewiththeaddedfeatureofanon-boardcomputer.Theon-boardcomputerisoftenreferredtoasthemachinecontrolunitorMCU.TheMCUusuallyhasanalphanumerickeyboardfordirectormanualdatainput(MDI)ofpartprograms

▲continuous-path(or

contouring)toolmovements▲incrementalpositioning▲closed-loop▲right-handcoordinatesystem▲left-handcoordinatesystem.▲Hydraulic▲pneumatic▲electric▲point-to-pointtoolmovements▲absolutepositioning▲open-loopMachiningcentresarethedevelopmentinCNCtechnology.Turningcenterswithincreasedcapacitytoolchangersarealsomakingstrongappearanceinmodernproductionshops.TheseCNCmachinesarecapableofexecutingmanydifferenttypesoflathecuttingoperationssimultaneouslyonrotatingpart.Inadditiontomachiningcentersandturningcentres,CNCtechnologyhasalsobeenappliedtomanyothertypesofmanufacturingequipment.Amongthesearewireelectricaldischargemachines(WEDM)andlasercuttingmachines.SessionOneCNCMachineSessionOneCNCMachineAclosed-loopsystem-Aclosed-loopsystemutilizestheservemotorwhosetypesincludeACservomotorisedservomotors.（）Anopen-loopsystem-Anopen-loopsystemutilizessteppingmotorstocreatemachinemovements.SessionTwoCNCProgrammingCanyoumakeclearthemeaningofthefollowingfigures?Surveyyourworkplacecarefullywithyourteammatesandtrytogiveeachofthemacorrespondinganswerfromtheanswersheetfollowingthefigures.（）machineaxisforathree-axisverticalCNCmachine（machineaxisdefinedasspindlemovement）（）machineaxisforathree-axishorizontalCNCmachine（machineaxisdefinedasspindlemovement）（）coordinatesystemforahorizontalmillingmachine（）coordinatesystemforaverticalmillingmachine（）machineaxesforsix-axisverticalCNCmachineSessionTwoCNCProgrammingSessionTwoCNCProgramming（）thewordsspecifywhichunits,whichinterpolator,absoluteorincrementalprogramming,whichcircularinterpolationplane,cuttercompensation,andsoon.（）definethreedimensional(andthreerotational)axes.（）specifyfeedandspeed.（）specifiestooldiameter,nexttoolnumber,toolchange,andsoon.（）specifydrillcycle,borncycle,millcycle,andclearanceplane.（）specifythecoolantcondition,thatis,coolanton/off,flood,andmist.SessionTwoCNCProgramming（）Point-to-pointtoolmovementscausethetooltoapointonthepartandexecuteanoperationatthatpointonly.（）Continuous-pathtoolmovementsaresonamedbecausetheycausethetooltomaintaincontinuouscontactwiththepartasthetoolcutsacontourshape.SessionTwoCNCProgrammingSessionThreeCNCMachiningCenter16.CONTROLPANEL17.POWERON/OFF18.RESET5.MDI6.HANDLE7.JOG8.CYCLESTART14.RAPIDTRAVERSEOVERRIDE15.MACHINELOCK9FEEDHOLD10SINGLEBLOCK11.dryrun19.CRTCHARACTERDISPLAY20.DISPLAY1.EMERGENCYSTOP2.MODESELECT3.EDIT4.MEMORY12REFERENCERETUR13.FEEDRATEOVERRIDESessionThreeCNCMachiningCenter（）Thecontentsofthecurrentlyactiveprogramareactivesequencenumberdisplay（）Thescreenisonwhichallthecharacters(addresses)anddataareshown（）Thisbuttonisusedforalarmingcancellationorcancellationofanoperation.（）Thecontrolisalwaysturnedonafterthemainpowerswitch,locatedonthedoorofthecontrolsystem（）Usually,thecontrolpanelislocatedatthefrontofthemainelectronicsystemandisequippedwithascreenandwithvariousbuttonsandswitches（）Thisswitchisusedtocheckanewprogramonthemachine.Allmovementsofthetoolareblocked,whileacheckisrunonthecomputerscreen.SessionThreeCNCMachiningCenter（）thismodeenablestheautomaticcontrolofthemachine.（）thismodeenablestheNCtocommandthememorytobeexecuted.（）thismodeenablesyouto:Entertheprogramtomachinememory,Enteranychangestotheprogram,Transferdatafromtheprogramtoatape,Checkthememorystoragecapacity.（）Usethisswitchtospecifytheoperationalmod.（）thisbuttonisredandislocatedinthelowerleftcornerofthecontrolpanel.SessionThreeCNCMachiningCenterInaCNCsystem,each_____________ofmotionisequippedwithaseparatedrivingsourcethatreplacesthehandwheeloftheconventionalmachine.Thedrivingsourcecanbe___________motor,a_______________,ora__________________.Thesourceselectedis______________mainlybasedontheprecisionrequirementsSessionThreeCNCMachiningCenterObserveyourworkplacewithyourcolleaguesthedifferentkindsoflathesalsothecomponentsofaCNClatheandthentryyourbesttofinishoffthefollowingtasks:task1,fillintheblanksinthefollowingfigures;task2,rememberthemwiththehelpofyourgroupmembers,thendictatethemforeachother.

ComponentsofaCNClatheSessionThreeCNCMachiningCenterhorizontalmachiningcenter加工中心turningcenter立式加工中心millingmachine电火花加工机床machiningcenter车削中心verticalmachiningcenter铣床CNCmachiningcenter数控加工中心coordinatesystem坐标系electro-dischargemachine卧式加工中心SessionOneCAD/CAMSoftwareManytoolpathsaresimplytoodifficultandexpensivetoprogrammanually.Forthesesituations,weneedthehelpofacomputertowriteanNCpartprogram.ThefundamentalconceptofCAD/CAMidthatwecanuseaCADdraftingsystemtodrawthegeometryofawokpieceonacomputer.Oncethegeometryiscompleted,thenwecanuseaCAMsystemtogenerateanNCtoolpathbasedontheCADgeometry

themodelisverified.theCAMsystemcreatestoolpaths.thegeometryisdefinedintheCADdrawingWorkinyourworkplaceandobservetheCAD/CAMsystemcarefullyandthentrytofillintheblanksinthefollowingfigures

SessionOneCAD/CAMSoftwareSessionOneCAD/CAMSoftwareWatchtheCADdrawingcarefullyinyourworkplaceanddiscussitwithyourgroupmembersthefourstepsfromaCADdrawingtotheworkingNCcodethenputthefollowingsentencesinrightorderwiththehelpofyourteammates.()ThefinalproductofCAD/CAMprocessistheNCcode.()ThegeometryisdefinedinaCADdrawing.()ThemodelisnestimportedintotheCAMmodule.()TheCAMmodelisthenverifiedtoensurethatthetoolpathsarecorrect.SessionTwoCAD/CAMcomponentsandfunctionsCAD/CAMsystemscontainbothCADandCAMcapabilities,eachofwhichhasanumberoffunctionalelements.TheCADportionofthesystemisusedtocreatethegeometryasaCADmodel.TheCADsystem,whetherstandaloneoraspartofaCAD/CAMpackage,tendstobeavailableinseveraldifferentlevelsofsophistication.Wireframescanbedifficulttovisualize,butallZ-axisinformationisavailablefortheCAMoperations.Solidmodelscanbeslicedopentorevealinternalfeaturesandnotjustathinskin.SessionTwoCAD/CAMcomponentsandfunctionsA.theCAMmoduleisusedtocreatethemachiningprocessmodelbaseduponthegeometrysuppliedintheCADmodel.B.theCAMsystemwillgenerateagenericintermediatecodethatdescribesthemachiningoperation,whichcanlaterbeusedtoproduceGandMcodeorconversationalprograms.C.theCAMmodulesalsocomeinseveralclassesandlevelsofsophistication.（）CAM模块也有多种类型和层次。（）CAM系统生成描述加工操作的普通中间代码，这些代码以后可以用来生成G和M代码或会话式程序。（）根据CAD模型提供的几何形状，CAM模块用于创建加工工艺模型。SessionTwoCAD/CAMcomponentsandfunctionsWeknowastandardCNCmachinetoolcan’tbeusedtodirectlyproduceanellipse.Howdowesolvethisproblem?Readthefollowingmaterialsandobservethefiguresfollowingthematerialsandthentrytofindouttheanswers.TheCAMsystemwillreconcilethisproblembyestimatingthecurvewithlinesegments.TheCAMsystemwillgenerateaboundinggeometryoneithersideofthetruecurvetoformatolerancezone.Smallertolerancezoneswillproducefinertoolpathsandmorenumerouslinesegments,whilelargertolerancezoneswillproducefewerlinesegmentsandcoarsertoolpaths.SessionTwoCAD/CAMcomponentsandfunctions1.OneimportantconceptwemustunderstandisthatthegeometryrepresentedbytheCADdrawingmaynotbeexactlythesamegeometrythatisproducedontheCNCmachinetool.

2.Tocreatethemachiningoperations,theCAMsystemwillneedtoknowwhichcuttingtoolsareavailableandwhatmaterialwearemachining.

3.Itiseasytorelyonthecomputertogeneratethecorrecttoolpath,butfinishedsurfacesarefurtherestimatedduringmachiningwithballendmills.

SessionTwoCAD/CAMcomponentsandfunctionsPureCADsystemsareusedinallareasofdesign,andvirtuallyanyproducttodayisdesignedwithCADsoftware.Gonearethedaysofpencilandpaperdrawings.ThismismatchsetsuptheclassicargumentbetweentheCADdesignersandtheCAD/CAMprogrammeronwhatisthebestwaytoapproachCAD/CAM.Thegreatertheacceptanceofthestandard,the