教学材料《汽车专业英语》-3

3AutomobileElectronicControlTechnologies汽车电控技术3.4ElectronicIgnitionSystem

电子点火系统3.5AutomaticTransmission

自动变速器3.6AutomaticTransmissionServiceandMaintenance

自动变速器的维修与保养下一页上一页3AutomobileElectronicControlTechnologies汽车电控技术3.7AntilockBrakingSystem

防抱死制动系统3.8ElectronicStabilityProgram

电子稳定程序3.9ActiveBodyControl

主动车身控制3.10AirBagSystem

安全气囊系统下一页上一页3AutomobileElectronicControlTechnologies汽车电控技术3.11ControllerAreaNetwork

控制器局域网3.12GlobalPositioningSystem

全球定位系统3.13CruiseControl

巡航控制3.14AutomobileAirConditioning

汽车空调下一页上一页3.1BasicPrinciplesofPetrolInjectionThefunctionofpetrol-injectionsystemsistosprayfuelinfinelyatomizedstateintotheinductedair.1Therequiredmixturequantityineachcaseandthemixtureratiomustbeadaptedtotherespectiveoperatingstateintheprocess.Infuel-injectionsystemsthefuelissprayedintotheairinfinelyatomizedstatewiththeaidofinjectorsandthepressurebuiltupbythefuelpump.Thisincreasesthesurfaceareaoftheinjectedfuel.Thiscausesthefueltocarburatemorequickly，whichleadstoimprovedmixingwithair，morecompletecombustionandbetterexhaust-gasvalues.2下一页返回3.1BasicPrinciplesofPetrolInjectionInthecaseofindirectinjection(exteriormixtureformation)，thefuelinjectorsarearrangedinsuchawayastoinjectintotheintakemanifoldorintothethrottle-valvehousing.Withthistypeofinjection，fuelandairalreadystarttobemixedoutsidethecombustionchamber.Auniformlydistributed，homogeneousfuel-airmixtureshouldbecreatedinthewholecombustionchamberduringtheinductionandcompressionstrokes.3Inthecaseofdirectinjection(interiormixtureformation)，thefuelinjectorsarearrangedinsuchawayastoinjectintothecombustionchamber.下一页返回上一页3.1BasicPrinciplesofPetrolInjectionElectroniccontrolofthesystemsisintendedoptimallytoadaptthefuel-airratio(quality)andtheamountofthemixturecreated(quantity)totherespectiveengineoperatingstate.Thefollowingdifferenttypesofinjectionareused:Single-pointInjection(SPI)Herethefuelisinjectedcentrallyintothethrottle-valvehousingbeforethethrottlevalve.Atomizationinthethrottle-valvegapandevaporationonhotintakewallsoradditionalheaterelementsimprovethepreparationofthefuel-airmixture.4下一页返回上一页3.1BasicPrinciplesofPetrolInjectionRoutesandmanifoldsofdifferentlengthscausethefuelnottobedistributeduniformlytoallthecylinders.Peripheralturbulenceespeciallyincoldenginesresultsinunequalmixtureformation.Single-pointinjectionsystemsaremuchsimplerindesignthantheirmultipointcounterparts.5MultipointInjection(MPI)Eachcylinderisassignedafuelinjector.Theseinjectorsaresituatedintheintakemanifoldusuallydirectlybeforetheinletvalves.Themixtureisthereforesubjecttointakepathsofequallengthanduniformdistribution.6下一页返回上一页3.1BasicPrinciplesofPetrolInjectionDirectInjectionSystemswithdirectinjectionarealwaysmultipointsystems.Thefuelishighlypressurized，andinjectedviaacommonrailfuellinedirectlyintothecombustionchamberofeachcylinder，asopposedtoconventionalmulti-pointfuelinjectionthathappensintheintakemanifoldorcylinderport.7Theinjectionnozzleisplacedinsidethecombustionchamber.Directinjectionenginesaregenerallymoreefficientandcleanerthanindirectinjectionengines.下一页返回上一页3.1BasicPrinciplesofPetrolInjectionNewWordsinjectionn.喷油，喷射sprayn./vt.喷射atomizevt.雾化，将……喷成雾状injectorn.喷油器pumpn.泵，抽水机v.抽，吸carburatev.汽化combustionn.燃烧exhaustv.排气n.排气装置intaken.进气chambern.室，膛下一页返回上一页3.1BasicPrinciplesofPetrolInjectioncompressionn.压缩stroken.行程atomizationn.雾化turbulencen.紊乱multipointa.多点的nozzlen.喷嘴PhrasesandExpressionsfuelinjector喷油器intakemanifold进气歧管throttlevalve节气门体combustionchamber燃烧室下一页返回上一页3.1BasicPrinciplesofPetrolInjectionfuel-airratio空燃比single-pointinjection(SPI)单点喷射(SPI)multipointinjection(MPI)多点喷射(MPI)directinjection直接喷射Notes1.Thefunctionofpetrol-injectionsystemsistosprayfuelinfinelyatomizedstateintotheinductedair.汽油喷射系统的功用是将燃料以微小的雾状喷射到被吸入的空气中。todo不定式做表语是对主语起补充说明作用。下一页返回上一页3.1BasicPrinciplesofPetrolInjection例如:Hiswishistobuyaluxuriouscarinthenearfuture.他的希望是在不远的将来买一辆豪华轿车。inducted被吸入的，过去分词做定语。单个分词做定语一般放在所修饰的名词前，如:boilingwater沸水，fallenleaves落叶。也可放在后面。如:theelementsknown已知元素。2.Thiscausesthefueltocarburatemorequickly，whichleadstoimprovedmixingwithair，morecompletecombustionandbetterexhaust-gasvalues.这样，能够使燃油汽化得更快，改善燃油与空气的混合状况，使燃烧更完全，从而降低废气排放。下一页返回上一页3.1BasicPrinciplesofPetrolInjectionwhichleadstoimprovedmixingwithair引导非限制性定语从句。causesb.orsth.todosth.使，促使。例如:Whatcausedhimtochangehismind?什么原因使他改变主张?3.Auniformlydistributed，homogeneousfuel-airmixtureshouldbecreatedinthewholecombustionchamberduringtheinductionandcompressionstrokes.均匀的燃油一空气混合气被平均地分配到各个气缸，并在进气与压缩冲程期间，充满整个燃烧室。下一页返回上一页3.1BasicPrinciplesofPetrolInjection4.Atomizationinthethrottle-valvegapandevaporationonhotintakewallsoradditionalheaterelementsimprovethepreparationofthefuel-airmixture.燃油在此通道内雾化，附在高温的进气管壁上或者附在加热装置上的燃油受热蒸发，从而改善预先混合的燃油一空气混合气质量。5.Single-pointinjectionsystemsaremuchsimplerindesignthantheirmultipointcounterparts.在设计上，单点喷射系统要比与此对应的多点喷射简单得多。much+形容词比较级，表示……得多。下一页返回上一页3.1BasicPrinciplesofPetrolInjection例如:Heismuchbettertoday.他今天好得多了。6.Themixtureisthereforesubjecttointakepathsofequallengthanduniformdistribution.因此，每个气缸的进气路径长度相等，混合气可以平均地分配。besubjectto以……为条件的，须经……的。例如:Theplanissubjecttoconfirmation.本计划须经批准。下一页返回上一页3.1BasicPrinciplesofPetrolInjection7.Thefuelishighlypressurized，andinjectedviaacommonrailfuellinedirectlyintothecombustionchamberofeachcylinder，asopposedtoconventionalmulti-pointfuelinjectionthathappensintheintakemanifoldorcylinderport.传统的多点喷射是将燃油喷入进气歧管或进气道内，与其相对，直接喷射是通过公共油轨将燃油以较高的压力直接喷入每个气缸的燃烧室内。asopposedto与……对照，与……成对比。例如:Iamhereonbusinessasopposedtoaholiday.我在这里是办公事而不是度假。下一页返回上一页3.1BasicPrinciplesofPetrolInjection译文汽油喷射的基本原理汽油喷射系统的功用是将燃料以微小的雾状喷射到被吸入的空气中。混合气的数量与混合比例都必须与每个工况相适应。在燃油喷射系统中，油泵给燃油增压，喷油器将燃料以微小的雾状喷到空气中，增加喷入燃油的表面积。这样，能够使燃油汽化得更快，改善燃油与空气的混合状况，使燃烧更完全，从而降低废气排放。在间接喷射(外部混合)的情况下，喷油器被安装在可以将燃油喷到进气歧管内或节气门体内的位置。在这种喷射方式下，燃油和空气在燃烧室外就已经开始混合。下一页返回上一页3.1BasicPrinciplesofPetrolInjection均匀的燃油一空气混合气被平均地分配到各个气缸，并在进气与压缩冲程期间，充满整个燃烧室。在直接喷射(内部混合)的情况下，喷油器被安装在可以将燃油直接喷到燃烧室内的位置。电控燃油喷射系统能够理想地调节各个工况下混合气的空燃比(质量)与数量。使用着的不同喷射类型如下。单点喷射(SPI)这种燃油喷射系统是将燃油集中喷入位于节气门前的节气门体内。燃油在此通道内雾化，附在高温的进气管壁上或者附在加热装置上的燃油受热蒸发，从而改善预先混合的燃油一空气混合气质量。由于混合气进入到每个气缸的路线与进气歧管的长度不同，很难将混合气均匀地分配到所有气缸。下一页返回上一页3.1BasicPrinciplesofPetrolInjection特别是在冷机时，外围的气流紊乱会导致混合气不均匀。在设计上，单点喷射系统要比与此对应的多点喷射简单得多。多点喷射(MPI)每个气缸都有一个喷油器，喷油器一般被直接安装在进气门前的进气歧管上。因此，每个气缸的进气路径长度相等，混合气可以平均地分配。直接喷射直接喷射系统一般也是多点喷射系统。传统的多点喷射是将燃油喷入进气歧管或进气道内，与其相对，直接喷射是通过公共油轨将燃油以较高的压力直接喷入每个气缸的燃烧室内。喷油嘴位于燃烧室内。直喷发动机一般比间接喷射发动机效率更高、更清洁。返回上一页3.2BasicsofElectronicsThemicroprocessorhastakenovermanyofthetasksincarsandtrucksthatwereformerlyperformedbyvacuum，mechanical，orelectromechanicaldevices.Atypicalelectroniccontrolsystemismadeupofsensors，actuators，andrelatedwiringthatistiedintoacentral

processorcalledamicroprocessorormicrocomputer.Thecentralprocessingunit(CPU)isthebrainofacomputerandisconstructedofthousandsoftransistorsplacedonasmallchip.1TheCPUbringsinformationintoandoutofthecomputer'smemory.下一页返回3.2BasicsofElectronicsTheinputinformationisprocessedintheCPUandcheckedagainsttheprograminthecomputer'smemory.TheCPUalsochecksthememoryforanyotherinformationregardingprogrammedparameters.TheinformationobtainedbytheCPUcanbealteredaccordingtotheinstructionsoftheprogram.TheCPUmaybeorderedtomakelogicdecisionsontheinformationreceived.Oncethesedecisions，orcalculations，aremade，theCPUsendsoutcommandstomaketherequiredcorrectionsoradjustmentstothesystembeingcontrolled.2下一页返回上一页3.2BasicsofElectronicsAllsensorsperformthesamebasicfunction.Theydetectamechanicalcondition(movementorposition)，chemicalstate，ortemperatureconditionandchangeitintoanelectricalsignalthatcanbeusedbythecomputertomakedecisions.3TheCPUmakesdecisionsbasedoninformationitreceivesfromthesensors.Eachsensorusedinaparticularsystemhasaspecificjobtodo(forexample，monitorthrottleposition，vehiclespeed，manifoldpressure).Togetherthesesensorsprovideenoughinformationtohelpthecomputerformacompletepictureofvehicleoperation.下一页返回上一页3.2BasicsofElectronicsEventhoughthereareavarietyofdifferentsensordesigns，theyallfallunderoneofthetwooperatingcategories:referencevoltagesensorsorvoltage-generatingsensors.4Oncethecomputer'sprogrammingdeterminesthatacorrectionoradjustmentmustbemadeinthecontrolledsystem，anoutputsignalissenttocontroldevicescalledactuators.Theseactuators，whicharesolenoids，switches，relays，ormotors，physicallyactonorcarryoutthecommandsentbythecomputer.5下一页返回上一页3.2BasicsofElectronicsActually，actuatorsareelectromechanicaldevicesthatconvertanelectricalcurrentintomechanicalaction.Thismechanicalactioncanthenbeusedtoopenandclosevalves，controlvacuumtoothercomponents，oropenandcloseswitches.WhentheCPUreceivesaninputsignalindicatingachangeinoneormoreoftheoperatingconditions，theCPUdeterminesthebeststrategyforhandlingtheconditions.6TheCPUthencontrolsasetofactuatorstoachieveadesiredeffectorstrategygoal.下一页返回上一页3.2BasicsofElectronicsNewWordselectronicsn.电子学microprocessorn.微机处理器vacuumn.真空a.真空的electromechanicala.机电的sensorn.传感器actuatorn.执行器microcomputern.微型计算机transistorn.晶体管chipn.芯片memoryn.存储器下一页返回上一页3.2BasicsofElectronicsprocessv.处理programn.程序parametern.参数commandn.指令functionn.功能monitorv.监测solenoidn.电磁线圈switchn.开关relayn.继电器motorn.电动机currentn.电流下一页返回上一页3.2BasicsofElectronicscomponentn.元件PhrasesandExpressionselectroniccontrolsystem电控系统centralprocessor中央处理器centralprocessingunit(CPU)中央处理器referencevoltagesensors基准电压式传感器voltage-generatingsensors生电式传感器electricalcurrent电流下一页返回上一页3.2BasicsofElectronicsNotes1.Thecentralprocessingunit(CPU)isthebrainofacomputerandisconstructedofthousandsoftransistorsplacedonasmallchip.中央处理器(CPU)是计算机的大脑，是由布置在一块小芯片上的成千上万个晶体管构成。placedonasmallchip过去分词短语做定语后置，修饰transistors。2.Oncethesedecisions，orcalculations，aremade，theCPUsendsoutcommandstomaketherequiredcorrectionsoradjustmentstothesystembeingcontrolled.下一页返回上一页3.2BasicsofElectronics一旦确定决策或计算出结果，CPU就会发出指令，对其所控制的系统按照要求进行修正或调整。beingcontrolled现在分词的被动式，做定语，修饰thesystem。3.Theydetectamechanicalcondition(movementorposition)，chemicalstate，ortemperatureconditionandchangeitintoanelectricalsignalthatcanbeusedbythecomputertomakedecisions.它们检测机械状态(运动或位置)、化学状态或温度状态，并将它们转变为可以被计算机用于决策的电信号。下一页返回上一页3.2BasicsofElectronicsthatcanbeusedbythecomputer为限制性定语从句，修饰anelectricalsignal。4.Eventhoughthereareavarietyofdifferentsensordesigns，theyallfallunderoneoftwooperatingcategories:referencevoltagesensorsorvoltage-generatingsensors.尽管传感器的设计各异，但它们均属于基准电压式传感器或者生电式传感器。eventhough尽管，即使，引导让步状语从句。例如:Hewillneverbedishonesteventhoughheshouldbereducedtopoverty.下一页返回上一页3.2BasicsofElectronics即使他沦为贫困，他也决不会不诚实。avarietyof若干不同的事物，种种。foravarietyofreasons由于种种原因。alargevarietyofpatternstochoosefrom可供选择的种类繁多的花样。fallunder归入……项下。例如:Theresultsfallunderthreeheads.这些结果分在二个项口下。5.Theseactuators，whicharesolenoids，switches，relays，ormotors，physicallyactonorcarryoutthecommandsentbythecomputer.下一页返回上一页3.2BasicsofElectronics这些执行器，即电磁线圈、开关、继电器、电动机，切实地执行计算机发出的命令。whicharesolenoids,switches,relays,ormotors为非限制性定语从句，用于说明actuators。sentbythecomputer过去分词短语做定语后置，修饰thecommand。6.WhentheCPUreceivesaninputsignalindicatingachangeinoneormoreoftheoperatingconditions，theCPUdeterminesthebeststrategyforhandlingtheconditions.当CPU收到一个表明工况变化的输入信号时，CPU确定处理该情形的最佳方案。下一页返回上一页3.2BasicsofElectronicsindicatingachange现在分词短语做定语后置，修饰aninputsignal。译文电子学基础在轿车和载货汽车上，微机处理器已经代替了很多以前使用的真空、机械或机电的装置。典型的电控系统由传感器、执行器和通过导线连接的中央处理器所组成，中央处理器被称为微机处理器或者微型计算机。中央处理器(CPU)是计算机的大脑，是由布置在一块小芯片上的成千上万个晶体管构成的。CPU将信息输入和输出计算机的存储器。输入的信息在CPU中进行处理，并与计算机存储器中的程序进行核对。下一页返回上一页3.2BasicsofElectronicsCPU还可以对存储器所存储的程序参数的任何信息进行检查，CPU可以根据程序指示调整所获得的信息。CPU可以按照指令对所接收到的信息进行逻辑决策，一旦确定决策或计算出结果，CPU就会发出指令，对其所控制的系统按照要求进行修正或调整。所有传感器的基本功能都是相同的。它们检测机械状态(运动或位置)、化学状态或温度状态，并将它们转变为可以被计算机用于决策的电信号。CPU根据它所接收到传感器的信息进行决策。在一个特定的系统中，每个传感器都有它明确的任务(例如，监测节气门位置、车速、歧管压力)。这些传感器一起向计算机提供足够的信息，以便计算机能够形成完整的车辆控制信息。尽管传感器的设计各异，但它们均属于基准电压式传感器或者生电式传感器。返回上一页3.2BasicsofElectronics当计算机根据程序决定必须对控制系统进行修正或调整时，计算机就会向名为执行器的控制装置输出信号。这些执行器，即电磁线圈、开关、继电器、电动机，切实地执行计算机发出的命令。执行器实质上是将电流转变为机械运动的机电装置。机械运动可以被用来开启和关闭阀门，控制其他元件的真空度，或者打开和关闭开关。当CPU收到一个表明工况变化的输入信号时，CPU确定处理该情形的最佳方案，然后通过控制一系列的执行器来实现预期的效果或策略目标。下一页返回上一页3.3ElectronicFuelInjectionSystemTheelectronicfuelinjection(EFI)systemcanbedividedintothreebasicsub-systems.Theyarethefueldeliverysystem，airinductionsystem，andtheelectroniccontrolsystem.Thefueldeliverysystemconsistsofthefueltank，fuelpump，fuelfilter，fueldeliverypipe(fuelrail)，fuelinjector，fuelpressureregulator，andfuelreturnpipe.Fuelismaintainedataconstantpressurebymeansofafuelpressureregulator.1Anyfuelwhichisnotdeliveredtotheintakemanifoldbytheinjectorisreturnedtothetankthroughafuelreturnpipe.2下一页返回3.3ElectronicFuelInjectionSystemTheairinductionsystemconsistsoftheaircleaner，airflowmeter，throttlevalve，intakemanifold，andintakevalve.Whenthethrottlevalveisopened，airflowsthroughtheaircleaner，throughtheairflowmeter(onLtypesystems)，pastthethrottlevalve，andthroughtheintakevalve，intotheengine.Airdeliveredtotheengineisafunctionofdriverdemand.3Asthethrottlevalveisopenedfurther，moreairisallowedtoentertheenginecylinders.4TheLtypeEFIsystemmeasuresairflowdirectlybyusinganairflowmeter.TheDtypeEFIsystemmeasuresairflowindirectlybymonitoringthepressureintheintakemanifold.下一页返回上一页3.3ElectronicFuelInjectionSystemTheelectroniccontrolsystemconsistsofvariousenginesensors，electroniccontrolunit(ECU)，fuelinjectorassemblies，andrelatedwiring.TheECUdeterminespreciselyhowmuchfuelneedstobedeliveredbytheinjectorbymonitoringtheenginesensors.TheECUturnstheinjectorsonforapreciseamountoftime，referredtoasinjectionpulsewidthorinjectionduration，todelivertheproperair-fuelratiototheengine.5Airenterstheenginethroughtheairinductionsystemwhereitis下一页返回上一页3.3ElectronicFuelInjectionSystemmeasuredbytheairflowmeter.6Astheairflowsintothecylinder，fuelismixedintotheairbythefuelinjector.Fuelinjectorsarearrangedintheintakemanifoldbehindeachintakevalve.TheinjectorsareelectricalsolenoidswhichareoperatedbytheECU.TheECUpulsestheinjectorbyswitchingtheinjectorgroundcircuitonandoff.Whentheinjectoristurnedon，itopens，sprayingatomizedfuelatthebacksideoftheintakevalve.Asfuelissprayedintotheintakeairstream，itmixeswiththeincomingairandvaporizesduetothelowpressuresintheintakemanifold.下一页返回上一页3.3ElectronicFuelInjectionSystemTheECUsignalstheinjectortodeliverjustenoughfueltoachieveanidealair-fuelratioof14.7:1，oftenreferredtoasstoichiometry.ThepreciseamountoffueldeliveredtotheengineisafunctionofECUcontrol.TheECUdeterminesthebasicinjectionquantitybaseduponmeasuredintakeairvolumeandenginerpm.TheECUmonitorsvariablessuchascoolanttemperature，throttleangle，andexhaustoxygencontentandmakesinjectioncorrectionswhichdeterminefinalinjectionquantity.下一页返回上一页3.3ElectronicFuelInjectionSystemNewWordsinjectionn.喷油，喷射sub-systemn.子系统filtern.过滤器，滤清器cylindern.气缸sensorn.传感器wiringn.导线circuitn.电路，一圈，巡回airstreamn.气流volumen.体积coolantn.冷却液下一页返回上一页3.3ElectronicFuelInjectionSystemPhrasesandExpressionselectronicfuelinjectionsystem(EFI)system电控燃油喷射系统fueldeliverysystem燃油供给系统airinductionsystem空气供给系统electroniccontrolsystem电控系统fueltank油箱fueldeliverypipe燃油分配管fuelrail油轨fuelpressureregulator燃油压力调节器fuelreturnpipe回油管下一页返回上一页3.3ElectronicFuelInjectionSystemaircleaner空气滤清器airflowmeter空气流量计throttlevalve节气门intakevalve进气门electroniccontrolunit(ECU)电控单元injectionpulsewidth喷油脉宽injectionduration喷油持续时间stoichiometry化学计算air-fuelratio空燃比injectionquantity喷油量下一页返回上一页3.3ElectronicFuelInjectionSystemNotes1.Fuelismaintainedataconstantpressurebymeansofafuelpressureregulator.燃油通过压力调节器可以使压力保持不变。bymeansof通过……手段。means方法，手段(常用作单数)。例如:Thoughtsareexpressedbymeansofwords.思想借文字表达出来。2.Anyfuelwhichisnotdeliveredtotheintakemanifoldbytheinjectorisreturnedtothetankthroughafuelreturnpipe.下一页返回上一页3.3ElectronicFuelInjectionSystem一些没有被喷油器喷到进气歧管内的燃油，通过回油管流回油箱。whichisnotdeliveredtotheintakemanifoldbytheinjector为定语从句，修饰anyfuel。3.Airdeliveredtotheengineisafunctionofdriverdemand.进入发动机空气流量的多少是根据驾驶员的要求而定的。deliveredtotheengine过去分词短语作定语后置，修饰air。4.Asthethrottlevalveisopenedfurther，moreairisallowedtoentertheenginecylinders.节气门开度大些，进入发动机气缸的空气流量就会多些。下一页返回上一页3.3ElectronicFuelInjectionSystemas做连词引导从句，可以表示原因、时间、伴随等。本句as引导状语从句表示时间。例如:Isawhimashewasgettingoffthebus.当他下公共汽车时，我看见了他。(表时间)Ashewasn'treadyintime,wewentwithouthim.因他未及时准备好，我们没有等他就先走了。(表原因)5.TheECUturnstheinjectorsonforapreciseamountoftime，referredtoasinjectionpulsewidthorinjectionduration，todelivertheproperair-fuelratiototheengine.ECU可通过控制喷油脉宽或者喷油持续时间来精确控制喷油器的开启时间，以实现适当的空燃比。下一页返回上一页3.3ElectronicFuelInjectionSystemreferredtoasinjectionpulsewidthorinjectionduration过去分词短语做定语后置，用于附加说明。6.Airenterstheenginethroughtheairinductionsystemwhereitismeasuredbytheairflowmeter.空气通过空气供给系统进入发动机，并由空气流量计进行测量。where地点副词，引导定语从句，修饰theengine。下一页返回上一页3.3ElectronicFuelInjectionSystem译文电控燃油喷射系统电控燃油喷射系统由三个基本的子系统组成，它们是燃油供给系统、空气供给系统和电控系统。燃油供给系统由油箱、燃油泵、燃油滤清器、燃油分配管(油轨)、喷油器、燃油压力调节器和回油管组成。燃油通过压力调节器可以使压力保持不变。一些没有被喷油器喷到进气歧管内的燃油，通过回油管流回油箱。空气供给系统由空气滤清器、空气流量计、节气门体、进气歧管和进气门组成。当节气门打开时，空气流经空气滤清器、空气流量计(L型)、节气门和进气门后进入发动机。下一页返回上一页3.3ElectronicFuelInjectionSystem进入发动机空气流量的多少是根据驾驶员的要求而定的。节气门开度大些，进入发动机气缸的空气流量就会多些。L型电控燃油喷射系统的进气流量是由空气流量计直接进行测量的。D型电控燃油喷射系统是通过测量进气歧管的压力间接进行测量的。电控系统由各种发动机传感器、电控单元(ECU)、喷油器总成以及相关的配线组成。ECU可以通过监测发动机的传感器与控制喷油器，精确控制供油量。ECU可通过控制喷油脉宽或者喷油持续时间来精确控制喷油器的开启时间，以实现适当的空燃比。下一页返回上一页3.3ElectronicFuelInjectionSystem空气通过空气供给系统进入发动机，并由空气流量计进行测量。在空气流进气缸时，喷油器将燃油喷入与空气混合。喷油器安装在进气歧管上，进气门的背侧。喷油器是电磁式的，由ECU控制。ECU是通过脉冲控制喷油器搭铁端的通断来控制喷油器的。当搭铁端被接通时，喷油器打开，将燃料以雾状喷到进气门的背侧。当燃料被以雾状喷到进气气流中时，由于进气歧管内压力低，燃油立即蒸发并与进入的空气混合。ECU通过脉冲信号控制喷油器喷入的燃油量，使混合气正好为理论空燃比14.7:1。供给发动机的燃油量是由ECU精确控制的，ECU根据测量的进气体积和发动机转速来确定基本的喷油量。ECU还监测冷却液温度、节气门开度以及废气中的氧含量等变量，来确定修正喷油量，从而确定最终的喷油量。返回上一页3.4ElectronicIgnitionSystemWhenadistributorisusedintheignitionsystem，thedistributordrivegear，shaft，andbushingsaresubjecttowear.Worndistributorcomponentscauseerraticignitiontimingandsparkadvance，which

resultsinreducedeconomyandperformanceplusincreasedexhaustemissions.Sincethedistributoriseliminatedinelectronicignition(EI)systems，ignitiontimingremainsmorestableoverthelifeoftheengine，whichmeansimprovedeconomyandperformancewithreducedemissions.1下一页返回3.4ElectronicIgnitionSystemDistributorsareseldomfoundontoday'sengines.Nearlyalloftoday'senginesareequippedwithanEIsystem.ThereareprimarilytwodifferentdesignsofEIsystems:double-endedcoilandcoil-per-cylindersystems.Double-endedignitionsystemsuseoneignitioncoilfortwosparkplugs.Bothendsofcoil'ssecondarysidearedirectlyconnectedtoasparkplug，whichmeansthattwoplugsareignitedatthesametime;oneisfiredonthecompressionstrokeofonecylinderandtheotherisfiredontheexhauststrokeofanother.下一页返回上一页3.4ElectronicIgnitionSystemCoil-per-cylinderignitionsystemshaveanindividualcoilforeachsparkplug.Therearetwodifferentdesignsofcoil-per-cylindersystemsusedtoday:thecoil-on-plug(COP)andtheseparatecoil.COPsystemsrelyonasingleassemblyofanignitioncoilandsparkplug.Inthesesystems，thesparkplugisdirectlyattachedtothecoilandthereisnosparkplugwire.2EIsystemconsistsofignitioncoil，computer，ignitionmodule，andvarioussensors，whichcombinetocontrolsparktiming.下一页返回上一页3.4ElectronicIgnitionSystemInmanyEIsystems，acranksensorlocatedatthefrontofthecrankshaftisusedtotriggertheignitionsystem.MagneticpulsegeneratorsandHall-effectsensorsarethemostwidelyusedenginepositionsensors.Theygenerateanelectricalsignalatcertaintimesduringcrankshaftrotation.Thecrankshaftsensorsignalprovidesenginespeedandcrankshaftpositioninformationtothecomputer.Thecomputercollectsandprocessesinformationtodeterminetheidealamountofsparkadvancefortheoperatingconditions.3下一页返回上一页3.4ElectronicIgnitionSystemThen，thecomputersignalsignitionmodulewhichcontrolthetimingoftheprimarycircuitinthecoils.Rememberthatthereismorethanonecoilinadistributorlessignitionsystem.Theignitionmodulesynchronizesthecoil'sfiringsequenceinrelationtocrankshaftpositionandfiringorderoftheengine.Therefore，theignitionmoduletakestheplaceofthedistributor.4下一页返回上一页3.4ElectronicIgnitionSystemNewWordsdistributorn.分电器coiln.卷，线圈plugn.塞，插头v.塞住，插入PhrasesandExpressionselectronicignitionsystem电子点火系统ignitiontiming点火正时double-endedcoil双点火线圈sparkplug火花塞compressionstroke压缩冲程下一页返回上一页3.4ElectronicIgnitionSystemexhauststrokecoil-on-plug(COP)ignitioncoilignitionmodulecranksensormagneticpulsegeneratorHall-effectsensorsdistributorlessignitionsystem排气冲程线圈火花塞点火线圈点火模块曲车由位置传感器磁脉冲传感器霍尔传感器无分电器点火系下一页返回上一页3.4ElectronicIgnitionSystemNotes1.Sincethedistributoriseliminatedinelectronicignition(EI)systems，ignitiontimingremainsmorestableoverthelifeoftheengine，whichmeansimprovedeconomyandperformancewithreducedemissions.因为电子(EI)点火系没有分电器，点火正时在发动机整个寿命内保持得更稳定，这意味着将改善发动机的经济性和降低排放性能。since引导原因状语从句。下一页返回上一页3.4ElectronicIgnitionSystem例如:Sinceyou'renotinterested，Iwon'ttellyouaboutit.既然你不感兴趣，那我就不告诉你了。whichmeansimprovedeconomyandperformancewithreducedemissions引导非限制性定语从句。2.Inthesesystems，thesparkplugisdirectlyattachedtothecoilandthereisnosparkplugwire.它是将点火线圈直接连接到火花塞上，没有火花塞高压线。beattachedto连接。下一页返回上一页3.4ElectronicIgnitionSystem例如:Manymajorissuesareattachedtothislegislation.许多重要事务同这项立法相联系。Theygainedinfluencebyattachingthemselvestoprominentcityinstitutions.他们通过与卓著的城市机构之间的联系而获得威望。3.Thecomputercollectsandprocessesinformationtodeterminetheidealamountofsparkadvancefortheoperatingconditions.电脑采集信息并进行处理，以确定发动机所处工况的最佳点火提前角。下一页返回上一页3.4ElectronicIgnitionSystem4.Theignitionmodulesynchronizesthecoil'sfiringsequenceinrelationtocrankshaftpositionandfiringorderoftheengine.Therefore，theignitionmoduletakestheplaceofthedistributor.点火模块使点火线圈的点火顺序与发动机的工作顺序及曲轴位置保持一致。因此，是点火模块取代了分电器。inrelationto关于，涉及。taketheplaceof代替。下一页返回上一页3.4ElectronicIgnitionSystem译文电子点火系统在使用分电器的点火系统中，分电器驱动齿轮、驱动轴、衬套容易磨损，会导致点火正时改变和点火提前，从而使发动机经济性与性能降低，排放增加。因为电子(EI)点火系没有分电器，点火正时在发动机整个寿命内保持得更稳定，这意味着改善了发动机的经济性和性能，降低了排放。分电器在现代发动机上已经很少见了，今天的发动机几乎都安装了EI系统。EI系统主要有两种不同类型:双点火线圈系统和每缸一个点火线圈系统。下一页返回上一页3.4ElectronicIgnitionSystem双点火线圈系统是两个火花塞共用一个点火线圈。点火线圈次级绕组的两端连接一个火花塞，这意味着两个火花塞将同时点火，一个是在气缸的压缩冲程点火，另外一个是在排气冲程点火。每缸一个点火线圈系统是在每个火花塞上装有一个单独的点火线圈。常见的每缸一个点火线圈系统有两种不同的类型:线圈火花塞(COP)和独立点火线圈。COP点火系统采用的是由线圈和火花塞组成的独立总成，它是将点火线圈直接连接到火花塞上，没有火花塞高压线。EI系统由点火线圈、电脑、点火模块和各种传感器组成，它们共同控制点火正时。在很多的EI系统中，点火系统是由安装在曲轴前端的曲轴位置传感器触发的。下一页返回上一页3.4ElectronicIgnitionSystem磁脉冲传感器和霍尔传感器是应用最广泛的发动机曲轴位置传感器，它们在曲轴转动到某个特定时刻产生一个电信号，并且将发动机的转速与曲轴位置信号提供给电脑。电脑采集信息并进行处理，以确定发动机所处工况的最佳点火提前角。然后，电脑向点火模块发送信号，点火模块控制点火线圈初级电路的点火时刻。无分电器点火系有不止一个点火线圈，点火模块使点火线圈的点火顺序与发动机的工作顺序及曲轴位置保持一直。因此，是点火模块取代了分电器。返回上一页3.5AutomaticTransmissionAtransmissionisapartofthedrivetrain.Thetransmissionisusedtotransfertheenginepowertothedrivewheels.Italsoallowsthedrivertochoosemorepower(1stgear)ormorespeed(4thor5thgear)bychangingthegearratio.Inanautomatictransmission，gearsarechangedautomatically，accordingtotheenginerpm，vehiclespeed，loadandotherfactors.Atypicalautomatictransmissionhasfourorfiveforwardgearsorspeeds.Someautomatictransmissionsalsohaveamanualshiftmodeallowingthedrivertoselectgearsmanually.1下一页返回3.5AutomaticTransmissionTochangethegearratio，mostautomatictransmissionsuseplanetarygears.2Atypicalplanetarygearconsistsofthreemainparts:outerringgear，innergear，calledsungear，andplanetarycarrierwiththreeorfoursmall

gearsthatareplacedbetweentheinnersungearandtheouterringgear.3Atanytime，oneofthepartsoftheplanetarygearcanbeconnectedtotheinputshaftleadingtotheengine，asecondpartcanbeheldstationaryandthethirdpartisconnectedtotheoutputshaft.下一页返回上一页3.5Aut