汽车工程专业英语DOC

1、Chapter1AutomotiveBasics(1) Todaysaveragecarcontainsmorethan15,000separate,individualpartsthatmustworktogether.Thesepartscanbegroupedintofourmajorcategories:body,engine,chassisandelectricalequipment。当今的车辆一般都由15000多个分散、独立且相互配合的零部件组成。这些零部件主要分为四类：车身、发动机、底盘和电气设备。1.1 Body(车身)(2) Thebodyisdesignedtokeeppa

2、ssengerssafeandcomfortable.Thebodystylingprovidesanattractive,colorful,modernappearanceforthevehicle.车身的设计要保证乘客安全舒适。车身的款式使得汽车看起来漂亮迷人、色彩斑斓、时尚前卫。1.2 Engine(发动机)(3) Theinternalcombustionengineismostcommon:thisobtainsitspowerbyburningaliquidfuelinsidetheenginecylinder.Therearetwotypesofengine:gasolinean

3、ddiesel.Bothenginesarecalledheatengines;theburningfuelgeneratesheatwhichcausesthegasinsidethecylindertoincreaseitspressureandsupplypowertorotateashaftconnectedtothetransmission.内燃机是最常见的，其动力来自气缸里液体燃料的燃烧。发动机有汽油机和柴油机两种，都称为热机燃料燃烧产生热量，使得气缸内气体压力升高，从而提供动力，带动连接变速器的轴旋转.1.3 Chassis(底盘)1.3.3 Suspension(悬架)(4)

4、Thepurposeofthecompletesuspensionsystemistoisolatethevehiclebodyfromroadshocksandvibrations,whichwillotherwisebetransferredtothepassengersandload.Itmustalsokeepthetiresincontactwiththeroadregardlessofroadsurface.整个悬架系统的作用是隔离来自路的冲击和振动对车身的影响，防止它们传递给乘客和货物。另外不论路面如何,悬架系统都应该保持轮胎和路的接触。1.3.4 Braking(制动)(5)

5、Drumbrakeshaveadrumattachedtothewheelhub,andbrakingoccursbymeansofbrakeshoesexpandingagainsttheinsideofthedrum.Withdiscbrakes,adiscattachedtothewheelhubisclenchedbetweentwobrakepads.在鼓式制动器上,制动鼓和轮毂连接，制动蹄张开压紧制动鼓内侧从而产生制动。在盘式制动器上，连着轮毂的制动盘，被紧紧夹在两个制动块之间。1.4 Electricalsystem(电气系统)(6) Theelectricalsystemsup

6、plieselectricityforthestarter,ignition,lightsandheater.Theelectricitylevelismaintainedbyachargingcircuit.电器系统为起动机、点火系、照明和加热设备提供电流。电流的大小由充电电路来维持。Chapter2InternalCombustionEngine2.1.2 EngineTerms（发动机条款）2）Linkingthepistonbyaconnectingrodtoaerankshaftcausesthegastorotatetheshaftthroughhalfaturn.Thepower

7、stroke"usesupthegas,someansmustbeprovidedtoexpeltheburntgasandrechargethecylinderwithafreshpetrol-airmixture:thiseontrolofgasmovementisthedutyofthevalves;得气体带动轴旋转半圈。作功冲程耗尽了所有的气体，这样就必须采取相应的措施排出废气以及向气缸内再充入新鲜的可燃混合气：气体的运动由气门来控。2.2.1 EngineBlock（发动机缸体）1）Theengineblockisthebasicframeoftheengine.Allot

8、herenginepartseitherfitinsideitorfastentoit.Itholdsthecylinders,waterjackets,andoilgalleries.Theengineblockalsoholdsthecrankshaft,whichfastenstothebottomoftheblock.缸体是发动机的基体。发动机其它的部件都安装或固定在缸体上，包括气缸、水套和油道，以及固定在缸体底部的曲轴等。2.2.2 CylinderSleeves（气缸套）2）Cylindersleevesareusedinengineblockstoprovideahardwear

9、ingmaterialforpistonsandpistonrings.Theblockcanbemadeofonekindofironthatislightandeasytocastwhilethesleevesusesanotherthatisbetterabletostandupwearandtear.Therearetwomaintypesofsleeves:dryandwet.缸体中的气缸套为活塞和活塞环提供了一种坚硬耐磨的材料。缸体可以采用某种重量轻且易铸造的铁来制造，而缸套使用的却是另一种更加耐磨损的材料成。主要有两种类型的气缸套：干缸套和湿缸套。2.2.3 CylinderHe

10、ad（缸盖）3）Thecylinderheadfastenstothetopoftheblock,justasarooffitsoverahouse.Theundersideformsthecombustionchamberwiththetopofthepiston.In-lineenginesoflightvehicleshavejustonecylinderheadforallcylinders;largerin-lineenginescanhavetwoormore.气缸盖安装在缸体的顶部，就像安在房子上的屋顶一样。缸盖的下方和活塞顶部形成燃烧室。轻型车上使用的直列发动机,所有气缸仅有一

11、个气缸盖，较大的直列发动机有两个或更多缸盖。2.2.5OilPanorsump（油盘或油底盖）4）Theoilpumpinthelubricatingsystemdrawsoilfromtheoilpanandsendsittoallworkingpartsintheengine.Theoildrainsoffandrunsdownintothepan.Thus,thereisconstantcirculationofoilbetweenthepanandtheworkingpatsoftheengine.润滑系的机油泵从油底壳抽出机油并把机油输送给发动机的所有工作部件。机油从油底壳流进流出.

12、因而在油底壳和发动机的工作部件之间就有机油定向循环流动。2.3.2 PistonAssembly（活塞总成）1）Mostpistonsaremadefromcastaluminum.Thepiston,throughtheconnectingrod,transferstothecrankshafttheforcecreatedbytheburningfuelmixture.Thisforceturnsthecrankshaft.大多数活塞由铝铸造而成。通过连杆的作用，活塞把可燃混合气燃烧产生的力传递给曲轴，带动曲轴旋转。2) Indieselengines,thecombustionchamb

13、ermaybeformedtotallyorinpartinthepistoncrown,dependingonmethodofinjection.柴油机发动机根据喷油方法不同，活塞头部可以形成全部燃烧室，也可以是燃烧室的一部分.3) PistonRings(活塞环)Inmodernengines,eachpistonhasthreerings.(PistoninolderenginesGasRingssometimeshadfourrings,orevenfive.)Theinsidesurfaceoftheringfitsinthegrooveonthepiston.Thering'

14、;soutsidesurfacepressesagainstthecylinderwalls.在新型发动机上，每个活塞有三个活塞环。(在老式发动机上，每个活塞有四个甚至五个活塞环)环的内侧装在活塞的环槽里，环的外表面紧压在气缸壁上。4) Theconnectingrodlittleendisconnectedtothepistonpin.Abushmadefromasoftmetal,suchasbronze,isusedforthisjoint.Thelowerendoftheconnectingrodfitthecrankshaftjournal.Thisiscalledthebigend

15、.连杆小头与活塞销连接，连接处有像青铜这样软金属制成的衬套，连杆下端连接在曲柄轴径上，称为连杆大头。5) N.B.No.4pistonisalwaysperformingthecompanionstroketoNo.1:whentheinletvalveinNo.4cylinderisfullyopen,No.1cylinderinletvalveisfullyclosed-thisfeatureisusefultorememberwhencheckingvalveclearances.注意4号活塞和1号活塞总是成对运行：1号气缸进气门全闭时，4号气缸进气门全开这个特点在检查气门间隙时是很有用

16、的。6) Aseachcylinderfires,itcausesthecrankthrowtospeedup.Theinertiaoftherestofshaftcauseittostayslightlybehind,resultinginatwistingactiononthecrankshaft.当一气缸点火时，使拐的转速提高，而轴的其它部分由于惯性作用，有所滞后,从而导致曲轴扭转。2.5:valvesystem(气门系统)1) Itisapparentfromthisdescriptionthattheexhaustvalvestaysopenforashortperiodoftime

17、duringwhichtheintakevalveisalsoopen.Inotherwords,theendoftheexhauststrokeandthebeginningoftheintakestokeoverlapforashortperiodoftime.Thisiscalledvalveoverlap.Valvetimingandvalveoverlapvaryondifferentengines.显而易见，排气门在进气门打开的一小段时间内也打开着。换句话说，排气冲程终了和进气冲程初期有一小段时间的重叠，这称为气门重叠。不同的发动机，其配气正时和气门重叠是不一样的。2) Eachc

18、ammustrevolveonceduringthefour-strokecycletoopenavalve.Acycle,remember,correspondswithtworevolutionsofthecrankshaft.Therefore,thecamshaftmustrevolveatexactlyhalfthespeedofthecrankshaft.Thisisaccomplishedwitha2:1gearratio.Agearconnectedtothecamshafthastwicethenumberofteethasagearconnectedtothecranksh

19、aft.在一个四冲程的循环里，每个凸轮转动一次来打开一个气门。在一个循环里曲轴是转动两圈的。因此，凸轮轴必须以曲轴转速的一半旋转，这是由2:1的传动比来实现的。连接凸轮轴的齿轮齿数是连接曲轴的齿轮齿数的2倍。2.6GasolineFuelSystem(汽油燃烧系统)1) Gasolinemustvaporizeeasily.Thischaracteristic,calledvolatility,isimportant.However,itmustnotvaporizetooeasily,oritwillturntovaporinsidethefueltankorfuellines.Inside

20、thefuelline,fuelvapormayblocktheflowofliquidgasoline.Thisiscalledvaporlock.Vaporlockiscommoninfuellineswheretheinletsideofthepumpisexposedtohightemperatures.汽油容易蒸发，这个重要的特性称为挥发性。但是汽油也不能挥发得过快，不然它会在油箱或油管里转变为蒸气。在油管中油蒸气会阻碍液态油的流动，这称为气阻。汽油泵的入口处易受高温，就经常出现气阻。2) Increasingthepressureofthefuelmixtureinthecombu

21、stionchamberbeforeignitionhelpstoincreasethepowerofanengine.Thisisdonebycompressingthefuelmixturetoasmallervolume.Highercompressionratiosnotonlyboostpowerbutalsogivemoreefficientpower.Butasthecompressionratiogoesup,knockingtendencyincreases.在点火前增加燃烧室内可燃混合气的压力有助于提高发动机的功率，这是通过把可燃混合气压缩到一个极小的体积来实现的。高的压缩

22、比不仅可以增加功率，而且会带来更多的有功率。但随着压缩比的增加，爆震的可能性也会增加。3) Fuelpump:Mostcarstodayhaveamechanicalfuelpump.Thispumpsfueloutofthetankandthroughthefuellinestothecarburetororinjectionsystem.Inmostcars,thepumpismountedontheengineblock.Somecarshaveanelectricfuelpump.Thispumpmountsinthefueltankwiththefuelpickupandthefue

23、l-gauge-sendingunit.当前大多数车采用机械油泵，油泵从油箱抽出油，通过油管送到化油器或喷射系统。大部分车的油泵安装在缸体上。一些车采用电动油泵，油泵安装在油箱上，附带有油量传感器和燃油表油量传送装置。4) Acarburetordeliversfuelinproportiontotheamountofairflowingthroughit.Asyoupressontheacceleratorpedal,thethrottlevalveopenswidertodrawmoreairthroughthecarburetorThecarburetorprovidesricheror

24、leanermixtures,dependingonanumberoffactors:enginespeed,load,temperature,andthrottleposition.Tomeetcomplicateddemands,acarburetorisahighlyintricatedevice,withmanyinternalpassagesandparts.化油器输送的燃油与流经化油器的空气量成一定比例。踩下加速踏板,节气门开度变大，化油器吸入的空气增加。化油器可提供较浓或较稀的混合气，这取决于发动机转速、负荷、温度和油门开度等因素。为满足复杂的要求，化油器的结构也很复杂，其上有很

25、多内部通道和部件。5) Thethrottlemechanismcontrolstheflowoftheair-fuelmixture.Thethrottlehasseveralparts,includingthethrottleshaftandthethrottleplate.Byopeningandclosing,thethrottleplatecontrolstheflowoftheair-fuelmixtureintotheengine.Moreairflowsinastheplateopens;lessairflowsinastheplatecloses.节气门机构控制着可燃混合气的

26、流量，包括节气门轴和节气门等部件。节气门的开启和关闭扌空制着进入发动机的可燃混合气流量。节气门开启，空气流量增加；节气门关闭，空气流量减少。2.7DieselEngine(柴油机)1) DieselenginegetsthisnamefromthepioneerworkdonebyDrRudolfDiesel.Thedieselisusedforthemajorityofheavyvehiclesandtheexcellentfueleconomymakesitanattractivealternativetothepetrolengineforlightcommercialvehicles,

27、deliveryvansandtaxis.柴油发动机的名称来源于RudolfDiesel博士所完成的开拓性工作。大多数重型车辆使用柴油，优良的燃油经济性使得柴油机成为具有吸引力的替代品，来代替轻型商用车、厢式运输货车和出租车上汽油机。2) Atexhaust-gasturbo-charging,theexhaust-gasenergywhichwouldhavebeenlostisusedtodriveaturbine.Thisturbinedrivesacompressorwhichaspiratesthecombustionairandsuppliesitpre-compressedtot

28、heengine.Inthisway，morefuelcanbesuppliedtothelargerairmassandtheenginepowerisincreased.Apositiveeffectisalsoexertedonthecombustionprocess.要丧失的废气能量用来驱动涡轮，涡轮驱动压缩机，压缩机吸入助燃空气，预压缩后送给发动机。这样，空气量多，供油也多，发动机功率就会增加，对燃烧过程也会带来积极作用。2.8.2 Thermostatcirculation(温扌空器循环)1) Whentheengineiscool，thethermostatremainsclos

29、edsothatcoolantcannotcirculatethroughtheradiator.Instead，coolantisrecirculatedwithintheengineblockandcylinderheaduntilthecoolantreachesapredeterminedtemperature.Atthattemperatureawax-likepelletexpandsinsidethethermostattoopenitandallowthecoolanttoflow.Today，mostoriginal-equipmentthermostatsopenatapp

30、roximately85oCto90oC.Inhotterclimates,a“cooler"thermostatmaybeusedtohelpavoidoverheating.节温器保持关闭，冷却水不能流通散热器进行循环，而是在发动机缸体和缸盖之间循环流动，一直到冷却水达到预定的温度为止。在该温度下，节温器中的蜡芯膨胀，从而打开节温器，使得循环水流经节温器。目前，多数原装节温器的开启温度大约在8590oC。气温较高时，可采用低温节温器防止发动机过热。2) Thepurposeofthelubricationsystemistocirculateoilthroughtheengine

31、.Anenginemusthaveagoodlubricationsystem.Withoutit,thefrictionheatfromthecontactofthemovingpartswouldwearthepartsandcausepowerloss.Oil,whenplacedbetweentwomovingparts,separatesthemwithafilm.Thisoilfilmpreventsthepartsfromrubbingagainsteachother.Thisoilfilmalsocushionstheparts,givingquieterandsmoother

32、engineoperation.润滑系统的作用是使机油在发动机里循环流动。发动机必须要有良好的润滑系统，不然移动部件相互接触摩擦而产生的热量磨损发动机部件，并损失发动机功率。机油位于两个移动部件之间，通过油膜隔开两部件。油膜防止部件之间的相互摩擦。它垫在部件之间，使得发动机工作安静、平稳可靠。3) ThreeTypesofharmfulemission(HC,CO,NOX):Therearemanycausesforemissions.Someemissionsarecausedbypoorairquality.Otheremissionsarecausedbyenginefuels,such

33、asdieselfuelorgasoline.Thesearehydrocarbonfuels,madeupprimarilyofhydrogenandcarbon.Emissionsarecolorlessandodorless.Sunlight,though,willtransformthemintosmog.产生排放的原因有很多，一部分排放物是由于空气质量差引起的，另一部分是由柴油或汽油等发动机燃料产生的。这些碳氢化合物燃料主要由碳和氢两种元素组成。这些排放物是无色无味的，在阳光的作用下转变为烟雾。2.10EmissionControl（排放扌空制装置）1）Exhaust-gasreci

34、rculationisamethodofreducingemissionsofoxidesofnitrogenthathasbeenknownandappliedforyears.Initsessentialcomponents,engineexhaustisaninertgas,i.e.anon-combustiblegas.废气再循环可降低氮氧化合物的排放，这种技术早已为人所知并应用多年。发动机废气的基本成分是一种惰性气体，也就是一种不易燃烧的气体。CHAPTER3POWERTRAIN（传动系统）1）Whenavehicleistobemovedfromresttheclutchmuste

35、ngageastationarygearboxshaftwiththeengine;thismustberotatingatahighspeedtoprovidesufficientpowerorelsetheloadwillbetoogreatandtheenginewillstall（cometorest）.变速器轴同发动机接合起来，此时发动机必须高速旋转以提供足够大的功率，否则载荷过大将引起发动机熄火。2）Thedrivingmember（主动部分）Thedrivingmemberconsistsoftwoparts:theflywheelandthepressureplate.Thef

36、lywheelisbolteddirectlytotheenginecrankshaftandrotateswhenthecrankshaftturns.Thepressureplateisboltedtotheflywheel.Theresultisthatbothflywheelandpressureplaterotatetogether.（p74）主动部分由飞轮和压盘两部件组成。飞轮用螺栓直接连接到发动机曲轴上，随曲轴旋转而旋转。压盘与飞轮连接，这样飞轮和压盘一起旋转。3）Thedrivenmember（从动部分）Thedrivenmember,orclutchdisc,islocate

37、dbetweentheflywheelandpressureplate.Thedischasasplinedhubthatlockstothesplinedinputshaftonthegearbox.Anyrotationoftheclutchdiscturnstheinputshaft.从动部分（或从动盘）位于飞轮和压盘之间。从动盘上有花键毂，连接着变速器上花键的输入轴。从动盘的旋转动变速器输入轴随之转动。4）Operatingmembers（操纵机构）Thesearethepartsthatreleasepressurefromtheclutchdisc.Theoperatingmemb

38、ersconsistoftheclutchpedal,clutchreturnspring,clutchlinkage,clutchfork,andthrowoutbearing.Theclutchlinkageincludestheclutchpedalandamechanicalorhydraulicsystemtomovetheotheroperatingmembers.操纵机构释放离合器盘的压力。操纵机构由离合器踏板、回位弹簧、离合器杆系、分离叉和分离轴承等组成。离合器杆系包括离合器踏板以及用来移动其它操纵部件的机械或液压操纵系统。3.4UniversalJoints(UJ万向节)1)

39、Thesuspensionconnectsthefinaldriveassemblytothecarbody.Thefinaldrivemovesupanddowninrelationtotheengineandtransmission.Acouplingisneededthatpermitsmovementbetweenthefinaldriveandtransmission.Theuniversaljointsprovidethiscoupling.悬架连接着主减速器(后桥)总成和车身。主减速器相对于发动机和变速器上下运动，这样在主减速器和变速器之间就需要万向节这种连接装置来允许其相对运动

40、。2) Ashaftwhichreceivesthedrivefromacrosstypejointvariesitsspeedduringrotation;thegreaterthedriveanglethegreaterthespeedvariation.Aconstantrotationalspeedcanberestoredbyfittingasecondjointinawaysuchthatwhenthefirstjointincreasesitsspeedthesecondjointdecreasesitsspeed.传动轴接收十字轴式万向节传来的动力，转动时其速度发生变化。传动角

41、越大，速度变化越大。要实现等速，必须以某种方式安装第二个万向节，这样第一个万向节使转速增大，第二个万向节就使转速减少。3) Planetarygearsareusedmainlyinfinaldrives,rear-mountedsplitterboxesand,aboveall,inautomatictransmissions.Thesimplestformofplanetarygear(theplanetary-geartrain)consistsofsungear,ringgearandarmwithplanetgears.Eachofthethreeelementsmayactasdr

42、ive,outputormaybeatrest.Therefore,greatvariationispossibleasregardsthetransmissionratio,rangingasfarasareversalofthedirectionofrotation.Theparallelmeshingofseveralgearsunderloadpermitsacompactconstruction.行星齿轮系主要应用在主减速器、后置副变速器和自动变速器上。最简单的行星齿轮系统由太阳轮、齿圈和行星轮组成。三部件中任意一个都可作输、输出或保持静止。这样，依照变速比的不同可得到较大的变速范围

43、，汽车的倒行也能实。承载齿轮的平行啮合使行星轮系结构较紧凑。4) Whenavehicleiscorneredtheinnerwheelmovesthroughashorterdistancethantheouterwheel.Thismeansthattheinnerwheelmustslowdownandtheouterwheelmustspeedup.Duringthisperioditisdesirablethateachdrivingwheelmaintainsitsdrivingaction.Thedifferentialperformsthesetwotasks.当汽车转弯时，内

44、侧车轮比外侧车轮行驶的距离要短，这说明内侧车轮比外侧车轮转得要慢。在此期间，维持每个驱动车轮的行驶状态是很重要的。这两个任务由差速器来完成。另：重点词句重点词语1. PowerTrain:传动系统2.Suspension:悬架3.Cylinder:气缸4.Transmission:变速器5.Gasoline:汽油机6.FinalDrive:主减速器，后桥7.LeafSpring:钢板弹簧8.Piston:活塞9.TDC:上止点10.Lubrication:润滑11.Muffler:消声器12.PlanetaryGear:行星齿轮13.DiscBrake:盘式制动器14.VentingSyste

45、m:通风系统15.Hybrid:混合动力重点句子一1 GasolineandDieselarecalledheatengines,theburningfuelgeneratesheatwhichcausesthegasinsidethecylindertoincreaseitspressureandsupplypowertorotateashaftconnectedtothepowertrain.汽油机和柴油机被称为热机，车用燃料产生热量使得气缸里的气体压力升高，为传动系统的曲轴提供动力。2 Anautomatictransmissionperformssimilarfunctionstoam

46、anualtransmissionexceptthatgearselectioniscontrolledeitherhtdraulicallyorelectronically.自动变速器选择档位由液压或者电控方式控制，其余方面，自动变速器和手动变速器的功能类似。3 Thepurposeofthecompletesuspensionsystemistoisolatethevehiclebodyfromroadshocksandvibrations,whichwillotherwisebetransferredtothepassengersandload.悬架系统的功能是隔离、缓减路面冲击和振动,

47、避免传递到车身,影响乘客和货物的舒适性和安全性。4 Allvehiclesmustfittedwithatleast2independentbrakesystems.Theywereoncecalledtheservicebrakeandtheemergencybrake所有汽车都必须配备两套独立的制动系统，即行车制动和紧急制动。5 Thepressuredevelopedwithinthecombustionchamberisappliedtotheheadofapistontoproduceausablemechanicalforce燃烧室内的压力作用在活塞顶部产生有用的机械功。6 Thevalvesystemismadeupofthosepartsneededtoopenandclosethevalvesatjusttherighttime.气门系统由那些在正确时间开启和关闭气门的零部件组成。7 Theburnedgasesremovedfromthecombustionchambercontainsuchharmfulemissionsashydrocarbons,carbonmonoxideandnitrousoxides.从燃烧室里排除的废气含有有害的成分：HC、CO和NOx8 Thel