机电专业英语第2版9Unit-9

Unit9TheConstructionofCNCMachine,数控机床的结构,CNCMachines,CNCMachines,ConstructionofCNCMachine,CNCMachines,TextCNCmachinetoolsarecomplexassemblies.Ingeneral,CNCmachinetoolconsistsofthefollowingunits:1ComputerAswithallcomputers,theCNCmachinecomputerworksonabinaryprincipleusingonlytwocharacters1and0,forinformationprocessingprecisetimeimpulsesfromthecircuit.Therearetwostates,astatewithvoltage,1,andastatewithoutvoltage,0.Seriesofonesandzeroesaretheonlystatesthatthecomputerdistinguishesacalledmachinelanguage,whichistheonlylanguagethecomputerunderstands.Whencreatingtheprogram,theprogrammerdoesnotcareaboutthemachinelanguage.Heorshesimplyusesalistofcodesandkeysinthemeaningfulinformation.Specialbuiltinsoftwarecompilestheprogramintomachinelanguageandthemachinemovesthetoolbyitsservomotors.However,theprogrammabilityofthemachineisdependentonwhetherthereisacomputerinthemachinescontro1.,Text2ControlsystemTherearetwotypesofcontrolsystemsonNCCNCmachines:openloopandclosedloop.Thetypeofcontrolloopuseddeterminestheoverallaccuracyofthemachine.Theopenloopcontrolsystemdoesnotprovidepositioningfeedbacktothecontrolunit.Theclosedloopcontrolsystemisveryaccurate.Ithasanautomaticcompensativefunctionforerror,sincethefeedbackdeviceindicatestheerrorandthecontrolmakesthenecessaryadjustmentstobringtheslidebacktotheposition.TheyapplyAC,DCorhydraulicservomotors.3DrivemotorsThedrivemotorscontrolthemachineslidemovementonNCCNCequipment.Theyfallintofourbasictypes:Steppermotorsconvertadigitalpulsegeneratedbythemicrocomputerunit(MCU)intoasmallsteprotation.Steppermotorsareusedinopenloopcontrolsystems,whileAC,DCorhydraulicservomotorsareusedinclosedloopcontrolsystems.,TextDirectcurrent(DC)servomotorsarevariablespeedmotorsthatrotateinresponsetotheappliedvoltage.Theyareusedtodrivealeadscrewandgearmechanism.DCservomotorsProvidehigher-torqueoutputthansteppermotors.Alternativecurrent(AC)servomotorsarecontrolledbyvaryingthevoltagefrequencytocontrolspeed.TheycandevelopmorepowerthanaDCservomotor.Theyarealsousedtodrivealeadscrewandgearmechanism.Fluidorhydraulicservomotorsarealsovariablespeedmotors.Theyareabletoproducemorepower,ormorespeedinthecaseofpneumaticmotorsthanelectricservomotors.ThehydraulicpumpprovidesenergytovalvesthatarecontrolledbytheMCU.,Text4.ToolchangersInacommonmachining,severaldifferentcuttingtoolsareusedtoproduceapart.Thetoolsmustbereplacedquicklyforthenextmachiningoperation.Forthisreason,themajorityofNCCNCmachinetoolsareequippedwithautomatictoolchangers,suchasmagazinesonmachinecenterandturretsonturningcenters.Theyallowtoolchangingwithouttheinterventionoftheoperator.,NewWordsandPhrases,NewWordsandPhrasesimpulseimplsn使表现突出compilekmpailvt编译，编辑，汇编programmabilitypru,rmbilti,-r-n可编程性，可编程序compensativekmpenstivadj可补偿的，赔偿的pneumaticnju:mtikadj气动的，有气胎的，充气的intervention,intvennn干涉，调停；妨碍inresponseto对应于，相对于，关于，就而论inthecaseof就而论，在情况下built-insoftware内置软件compensativefunction补偿功能,NewWordsandPhrasesdigitalpulse数字脉冲gearmechanism齿轮机构higher-torqueoutput高力矩输出，高扭矩输出voltagefrequency电压频率pneumaticmotor气动电动机hydraulicpump液压泵toolchanger换刀，换刀装置,Languagepoints,1.Aswithallcomputers，theCNCmachinecomputerworksonabinaryprincipleusingonlytwocharacters1and0,forinformationprocessingprecisetimeimpulsesfromthecircuit.译文：与所有计算机一样，数控机床的计算机也是根据二进位制原理，只有两个字符1和0作为电路的时间脉冲信息。说明：句中“aswith”意思是“asitisthecasewith”像.一样，正如例如：Aswithhappinessitself,thisislargelyyourdecisiontomake.是否与快乐为伴，很大程度上取决于你的选择。Aswithanytechnology,notallusesofAIwillbeforthebetter.与某些技术一样，并非所有的人工智能都有益处。,Languagepoints,2.Seriesofonesandzeroesaretheonlystatesthatthecomputerdistinguishesacalledmachinelanguage,whichistheonlylanguagethecomputerunderstands.译文：1和0的序列是计算机区别机器语言的唯一途径，也是计算机可以理解的唯一语言。说明：thatthecomputerdistinguishesacalledmachinelanguage为限定性定语从句修饰theonlystates；而whichistheonlylanguagethecomputerunderstands.为非限定性定语从句，解释说明名词短语acalledmachinelanguage。,Languagepoints,3.Whencreatingtheprogram,theprogrammerdoesnotcareaboutthemachinelanguage.译文：当编辑一个程序时，程序编辑人员不必关心机器语言。说明：句中Whencreatingtheprogram为现在分词短语做时间状语，可扩展为时间状语从句。4.However,theprogrammabilityofthemachineisdependentonwhetherthereisacomputerinthemachinescontro1.译文：然而，机床的可编程序性取决于机床控制系统中是否有计算机。说明：dependenton取决于，依靠，依赖whetherthereisacomputerinthemachinescontro1.该句为宾语从句，作介词on的宾语。,Languagepoints,Watersboilingpointisdependentonitspressure.水的沸点取决于气压。Everythingthatacomputerdoesisdependentonthemanwhousesit.计算机所做的一切都取决于使用计算机的人。5.ThehydraulicpumpprovidesenergytovalvesthatarecontrolledbytheMCU.译文：液压泵将能量提供给由微机单元控制的阀门。说明：句中thatarecontrolledbytheMCU为定语从句修饰valves。,ExerciseI.Answerthefollowingquestions.1.IstheCNCmachinecomputerasthesameasacommoncomputer?Yes，itis.2.HowmanytypesofcontrolsystemsarethereonNCCNCmachines?Whatarethey?TherearetwotypesofcontrolsystemsonNCCNCmachines:openloopandclosedloop.3.Howmanytypesofdrivemotorsarethere?Whatarethey?Drivemotorsfallintofourbasictypes:Steppermotors,Directcurrent(DC)servomotors,Alternativecurrent(AC)servomotors,andFluidorhydraulicservomotors.,Key,Key,Key,ExerciseII.Placea“T”(true)oran“F”(false)besidethesentencesaccordingtothetext.1.CNCmachinetoolsareverysimpleassemblies.2.Whencreatingtheprogram,theprogrammerdoesnotcareaboutthemachinelanguage.3.Theopenloopcontrolsystemdoesnotprovidepositioningfeedbacktothecontrolunit.4.Directcurrent(DC)servomotorsareinvariablespeedmotorsthatrotateinresponsetotheappliedvoltage.5.Fluidorhydraulicservomotorsarevariablespeedmotors.,Key,F,Key,T,Key,T,Key,T,Key,F,Exercise6.ThemajorityofNCCNCmachinetoolsareequippedwithautomatictoolchangersandtheyallowtoolchangingwithouttheinterventionoftheoperator.III.TranslatethefollowingsentencesintoChinese.1.WhenNCmachinesareperformedundercomputersupervision,itiscalledComputerNumericalControl.当数控机床在计算机控制下工作时就叫做计算机数控机床。2.Theclosedloopcontrolsystemisveryaccurateandithasanautomaticcompensativefunctionforerror.闭环控制系统非常精确。它具有误差的自动补偿功能。,Key,T,Key,Key,Exercise3.Ingeneral,CNCmachinetoolconsistsofthefollowingunits:computer,controlsystems,drivemotors,toolchangers.一般说来，数控机床由计算机、控制系统、驱动电动机和换刀装置等几个部件组成。4.Mostofthetime，severaldifferentcuttingtoolsareusedtoproduceapart.通常，加工一个零件需要使用几把不同的刀具。,Key,Key,TranslatingSkills,被动语态的译法由于科技文章需要描述客观事物的性质、特征、生产工艺流程与科学实验的结果等，并且通常不需要说明从事这些活动的执行者，因而被动语态在科技英语及专业英语中被广泛使用。因为英汉两种语言在表达上存在巨大差异，因此在将英语的被动句式翻译成汉语时应作一些改变，以适应汉语表达习惯。常见的翻译方法如下：一、译成汉语主动句Allbodiesareknowntopossesweight.人们知道所有物体都有质量。（加施动者）Thelatheisbeingadjustedbytheoperator.操作员正在调试那台车床。（将主语译成宾语）,TranslatingSkills,Themechanicalenergycanbechangedbackintoelectricalenergybymeansofagenerator.利用发电机，可将机械能再转变成电能.（无主语主动句）Inacommonmachining，severaldifferentcuttingtoolsareusedtoproduceapart.在普通加工中，加工一个零件使用几把不同的刀具。（同上）二、译成汉语被动句为了句子表达的需要，用“被”、“由”、“受”、“靠”、“给”、“遭”等汉语中表达被动概念的介词引导出施动者。Thesaddle，whichismountedonthehardenedandgroundbed-ways.滑板被安装在淬硬与研磨的导轨上。,TranslatingSkills,Thebedisusuallymadeofhigh-qualitycastiron.床身通常是由优质的铸铁制造成的。Thetoolcanbeautomaticallycalledforusebythepartprogram.刀具有零件程序自动调用。三、由“by”或“in”引导的状语通常可以转换为汉语句子的主语Productioncostshadbeenreducedbytheworkers.工人们已经把生产成本降下来了。StoragecapacityisgenerallyprovidedintheMCUforanycannedcycle.通常机床数控装置(MCU)提供用于固定循环的存储空间。,TranslatingSkills,四、常采用句型“It+被动语态+that”的译法Itissaidthat据说Itisbelievedthat人们认为Itisknownthat众所周知Itisexpectedthat人们希望Itisnotedthat人们注意到Itisannouncedthat有人宣称,ReadingMore,ThecomponentsofCNCmachines数控机床的部件ThemaincomponentsofCNCmachiningcentersarethebed,saddle,column,table,servomotors,ballscrews,spindle,toolchanger,andthemachinecontrolunit.数控加工中心的主要部件是床身、滑板、立柱、工作台、伺服电动机、滚珠丝杠、主轴、换刀装置和机床控制单元(图9-1)。,ReadingMore,BedThebedisusuallymadeofhigh-qualitycastironwhichprovidesforarigidmachinecapabilityofperformingheavy-dutymachiningandmaintaininghighprecision.Hardenedandgroundwaysaremountedtothebedtoproviderigidsupportforalllinearaxes.床身床身通常是由优质的铸铁制造成的，使机床足够坚固能够完成重载加工与高精度加工。床身上安装了淬硬与研磨的导轨以便为所有线性轴线提供刚性的支撑。,ReadingMore,SaddleThesaddle,whichismountedonthehardenedandgroundbed-ways,providesthemachiningcenterwiththeXaxislinearmovement.滑板滑板被安装在淬硬与研磨的导轨上，为加工中心提供了x轴的线性位移。ColumnThecolumn,whichismountedtothesaddle,isdesignedwithhightorsionstrengthtopreventdistortionanddeflectionduringmachining.ThecolumnprovidesthemachinecenterwiththeYaxis1inearmovement.立柱立柱安装在滑板上，此设计用来提供高抗扭强度以防止在加工过程中出现变形与偏斜，立柱为加工中心提供了Y轴的线性位移。TableThetable,whichismountedonthebed,providesthemachiningcenterwiththeZaxislinearmovement.工作台工作台安装在床身上，为加工中心提供了z轴的线性位移。,ReadingMore,ServosystemTheservosystem,whichconsistsofservodrivemotors,ballscrew,andpositionfeedbackencoders,providesfast，accuratemovementandpositioningoftheXYZaxesslides.Thefeedbackencodersmountedontheendsoftheballscrewsformaclosed-loopsystemwhichmaintainsconsistenthigh-positioningunidirectionalrepeatabilityof+0.003mm.伺服系统伺服系统由伺服驱动电动机、滚珠丝杠和定位反馈编码器组成，能确保XYZ轴的运动和定位精确而快速。反馈编码器安装在滚珠丝杠的两端形成一个闭环系统，闭环系统则保持一个稳定的高精度定位，单向重复误差为+O003mm。SpindleThespindle,whichisprogrammablein1rminincrements,hasaspeedrangeoffrom20to6000rmin.主轴主轴可在1转分增量范围编程，速度范围在每分钟206000之间。,ReadingMore,ToolchangersTherearebasicallytwotypesoftoolchangers:theverticaltoolchangerandthehorizontaltoolchanger.Thetoolchangeriscapableofstoringanumberofpresstoolswhichcanbeautomaticallycalledforusebythepartprogram.Toolchangersareusuallybidirectional,whichallowsfortheshortesttraveldistancetorandomlyaccessatool.换刀装置有两种基本类型的换刀装置：立式换刀装置和卧式换刀装置。换刀装置能够储存一定数量的刀具，并且可以自动地被零件程序调用。刀库中刀具的更换通常是双向的，从而允许在最短的距离任意地存取刀具。,ReadingMore,MCUTheMCUallowstheoperatortoperformavarietyofoperationssuchasprogramming,machining,diagnosis.NewerMCUsarebecomingmoresophisticated.Makingmachinetoolsmorereliableandtheentiremachiningoperationslessdependentonhumanskills.机床控制单元机床控制单元使操作者能完成各种各样的工作，诸如：编程、加工、诊断等。比较新型的机床控制单元已经变得更高级，可以使机床更可靠，并且整个加工工作对员工的技能的依赖更少。FortheCNClathe(Fig.9-2),thecomponentsareasfollow:BedThebedofaCNClatheisofasupportfunction,forexample,thetailstock,andusuallyslantedtoallowchipstofallawayeasily.数控车床(图9-2)，由下列部件组成。床身数控车床的床身具有支撑功能，如尾座，且通常是倾斜以便铁屑容易落下。,ReadingMore,HeadstockTheheadstockcontainsthespindleandtransmissiongearingusedtorotatethespindle.ChuckThechuckconnectstothespindleandclampstheworkpiece.主轴箱主轴箱包括主轴和用来转动主轴的齿轮传动机构。夹盘夹盘与主轴联接并且夹紧工件。TurretTheturretholdsthecuttingtoolandreplacesanoldtoolwithanewtoolduringatoolchange.CarriageThecarriagemovesthecuttingtoolintotherevolvingworkpiece.Itcontainsthesaddle，crossslide，andapron.转塔刀架转塔刀架用来夹持切削刀具，并且在刀具进行更换时用一把新刀具替换旧刀具。拖板拖板把切削刀具转换成为旋转的工件，包括：滑板、横向拖板和拖板箱。,ReadingMore,TailstockThetailstocksupportstherightendoftheworkpiece.SlantbedTheslantbedsupportsallthecomponentslistedaboveaswellasprovidingapathforchipsastheyfall.尾座T尾座支撑工件的右端部。倾斜床身倾斜床身支撑着上面列出的所有部件，并且为落下的铁屑提供了途径。,NewWordsandPhrasessaddlesdln.鞍，鞍状物，滑板columnklmn.立柱，圆柱，柱状物，专栏rigidrididadj.刚性的，坚硬的，固定的，严格的linearliniadj.直线的，直线型的，线状的torsiont:nn.扭转，扭力，转矩，韧性deflectiondifleknn.偏转，偏斜carrierkrin.托板，底盘，拖板，刀架，溜板，滑鞍panelpnln.面板，嵌板，仪表板encoderenkudn.译码器，编码器，编码员incrementinkrimntn.增加；增量；增额；盈余consistentknsistntadj.一致的，一贯的，始终如一的，相容合的unidirectional,ju:nidireknladj单向的，单向性的repeatabilityripi:tbilitin.可重复性，反复性，再现性,NewWordsandPhrasesbidirectional,baidireknladj.双向的;双向作用的randomlyrndmliadv.任意地，随便地，随机地accesskses,kssn.接近，通路，进入，存取，捷径diagnosis,dainusisn.诊断，分析，判断sophisticatedsfistikeitidadj.复杂的，高级的，久经世故的slantsl:nt,slntv.(使)倾斜，歪向；n.倾斜transmissiontrnzmin,trns-n.播送，发射，传送，传输，转播clampklmpn夹子，夹具，夹钳，压板，压铁；vt夹住，夹紧aproneiprnn拖板箱；停机坪；舞台口bed-way床身导轨fallaway脱落,NewWordsandPhrasesballscrew滚珠丝杠rigidsupport刚性支撑torsionstrength抗扭强度indexingtable分度工作台toolstorage刀具贮藏，刀具库存toolinterchangearm刀具交换臂traveling-column行程立柱spindlecarrier主轴托板，主轴底盘，主轴拖板，主轴刀架CNCpanel计算机数控面板feedbackencoder反馈编码器traveldistance行程距离，行程间距transmissiongearing齿轮传动机构crossslide横向拖板,ExerciseI.Answerthefollowingquestions.1.WhatarethemaincomponentsofCNCmachiningcenters?Theyarethebed,saddle,column,table,servomotors,ballscrews,spindle,toolchanger,andthemachinecontrolunit.2.Whatdoestheservosystemconsistsof?Theservosystemconsistsofservodrivemotors,ballscrew,andpositionfeedbackencoders,providesfast，accuratemovementandpositioningoftheXYZaxesslides.3.WhichcomponentsaretheCNClathemadeof?TheCNClatheismadeofthebed,theheadstock,thechuck,theturret,thecarriage,thetailstockandtheslantbed.,Key,Key,Key,ExerciseII.TranslatethefollowingphrasesintoEnglish.1.优质铸铁3.抗扭强度5.反馈编码器7.刚性支撑2.线性位移4.滚珠丝杠6.齿轮传动机构8.高精度加工1.high-qualitycastiron3.torsionstrength5.feedbackencoder2.1inearmovement4.ballscrew6.transmissiongearing7.rigidsupport8.highprecisionmachining,Key,参考译文ReadingMore数控机床的部件数控加工中心的主要部件是床身、滑板、立柱、工作台、伺服电动机、滚珠丝杠、主轴、换刀装置和机床控制单元(图9-1)。床身床身通常是由优质的铸铁制造成的，使机床足够坚固能够完成重载加工与高精度加工。床身上安装了淬硬与研磨的导轨以便为所有线性轴线提供刚性的支撑。滑板滑板被安装在淬硬与研磨的导轨上，为加工中心提供了x轴的线性位移。立柱立柱安装在滑板上，此设计用来提供高抗扭强度以防止在加工过程中出现变形与偏斜，立柱为加工中心提供了Y轴的线性位移。工作台工作台安装在床身上，为加工中心提供了z轴的线性位移。,参考译文ReadingMore伺服系统伺服系统由伺服驱