汽车专业毕业设计外文翻译

附录：英汉比较AutomotiveoxygensensorfailureandinspectionofthecommonTheautomotiveindustryiscurrentlyintheinternationalapplicationofthesensorononeofthelargestmarkets,andtheoxygensensorreportedthenumberofpatents,rankingthefirstinautomotivesensors.Oxygensensorinstalledinthevehicleexhaustpipe,useittodetecttheoxygencontentinexhaustport.Oxygensensorandthuscanbeobtainedinaccordancewiththesignal,putitbacktothecontrolsystemtofine-tunethefuelinjection,sothatA/Fcontrolatbest,notonlygreatlyreducesemissionsandsavesenergy.Atpresent,thepracticalapplicationoftheoxygensensorhaszirconiadioxideoxygensensorsandthetwooxygensensors.Andcommonoxygensensorandasinglelead,double-leadandleadofthreepoints;singlepinforZirconiaoxygensensor;doubleleadforthetitaniumdioxideoxygensensor;three-leadtypefortheheatingoxygenzirconiasensors,inprinciple,leadthewayonthreeoftheoxygensensorisnotasubstituteforuse.Areoneofthemostwidelyusedtypeofzirconiaoxygensensor.First,zirconiaoxygensensorstructureIntheuseofthree-waycatalyticconverterstoreduceexhaustpollutionontheengine,oxygensensorsareessentialcomponents.Oxygensensorislocatedinthefirstsectionoftheexhaustpipe,catalyticconverteratthefront.ThereisaOxygenSensorzirconia(aceramic)componentsmanufacturers,allofitsoutsidehasalayerofthin-platedplatinum.Zirconiaceramicplatedbodyatoneendwithathinlayerofplatinumclosed.Intotheprotectionofthelatterwasset,andinstalledinametalbody.Furtherprotecttheprotectionoftheroleofsetsplayedandsensorcanbeinstalledontheexhaustmanifold.Ceramicexhaustexternalexposure,andtheinternalatmosphereandtheenvironmentthesame.Thiscomponenthasaveryhightemperatureresistance,lowtemperaturesodonotallowcurrentthrough.However,whenhightemperature,becauseoftheairandexhaustgasoxygenconcentrationdifference,oxygenionscan,throughthiscomponent.Thisraisesthepotentialdifference,platinumtoenlarge.Inthisway,air-fuelratiolowerthanthetheoreticalair-fuelratio(thick),thecomponentsintheoxygensensorin(air)outside(theatmosphere)betweentheoxygenconcentrationhasagreaterbad.Thus,thesensorshavearelativelystrongonevoltage(JohnsonV).Ontheotherhand,iftheraregasmixture,airandexhaustgasoxygenconcentrationdifferencebetweentheverysmall,haveasensor,thereisonlyonerelativelyweakvoltage(near0volts).Becauseoncethemixtureofair-fuelratiodeviationfromthetheoreticalair-fuelratio,ternarycatalystsforCO,HCandNOXpurificationcapacitywillbeasharpdecline,itisinstalledattheexhaustpipeoxygensensorfordetectingoxygenconcentrationintheexhaust,andECUtheissueoffeedbacksignal,andthenbythe1ECUtocontrolfuelinjectionamountofinjectorchange,whichwillcontrolthemixtureattheair-fuelrationearthetheoreticalvalue.Two,automotiveoxygensensorworkingprincipleOxygensensorinstalledintheexhaustmanifold,itcandetecttheconcentrationofoxygenintheexhaust,air-fuelratiocalculated,andtheresultssenttotheECU.Forexample:1,exhaustgasoxygenconcentrationinthehigh–Whenemissionsaresignificantwhenthepercentageofoxygen,ECUwillaccordinglydeterminetheair-fuelratio,andthatisverydilutemixture.2,exhaustgasoxygenconcentrationinthelow–Whenthepercentageofoxygenintheexhaustvery,ECUtodetermineair-fuelratiowillaccordinglysmall,thatisverystrongmixture.Temperaturehigherthan℃,theceramicmaterialsusedfortheironconductor.Undertheseconditions,ifthepercentageofoxygensensorsonbothsidesofthedifferentcontentwillhaveavoltagechangeatbothends.Twotypesofenvironment(air-sideandexhaustside)ofthedifferentmeasurementsoftheoxygencontentofthesechangestellECU,exhaustattheoxygencontentintheremainderofthegenerationofharmfulemissionstoensurethatcombustionisnotappropriatepercentage.Ceramicmaterialsattemperatureslowerthan300℃arenon-linear,andthusthesensorisnotausefulsignaltransmission.ECUhasaspecialfunction,thatis,heatingmachineatpm(open-loopoperation)tostoptheadjustmentofthemixture.Sensorsequippedwithheatingelementstoreachoperatingtemperaturequickly.Whencurrentflowsthroughtheheatingelements,itreducestheirontomakeceramicsbecomeconductorsoftime,andwhichmakesthesensorcanbeinstalledintheexhaustpipeofthesitelater.Inthethree-waycatalyticpurifierMedium,ECUusingdatafromtheoxygensensortoregulatetheair-fuelratio,butthemethodofstandardCarburetorEFIdevicesomewhatdifferent.AtEFIdevice,EFI'sECUfuelinjectionthroughtheincreaseordecreasefromtheinjectedfuelvolume,adjustingair-fuelratio.IftheECUfromtheoxygensensordetectsthemixturetoothick,itwillgraduallyreducetheamountoffuelinjection,themixtureofon-thinning.Thereforetheactualair-fuelratiobecomesgreaterthanthetheoreticalair-fuelratio(moredilute).Whenthishappens,ECUthroughtheoxygensensortodetectthetruth,itwillstartagradualincreaseinthevolumeofspray.Inthisway,air-fuelratioistoolow,somewillLuan(moredense)untiltheair-fuelratiolowerthanthetheoretical.Thus,thecyclerepeated,ECUmaincloudinthisway,constantchangesinair-fuelratio,theactualair-fuelrationearthetheoreticalair-fuelratio.Carburetorintheuseofthedevice,areenteredbyregulatingairintakeair-fuelratioofair-conditioning.Mixturetheoryisusuallyair-fuelratiotomaintainalittlethick.ECUwithintheair-fuelratiooxygensensorhasbeentheinformation,andmanipulation,accordingtotheactualair-fuelratioEBCU(electronicallycontrolledintakevalve)regulatorintothecarburetorairintakevolume.Ifmixtureistoostrong,itallowsmoreairtoenterto-thinning:Ifmixtureistoothin,itallowslessairtoenter,2sothatmoreThird,thecommonautomotiveoxygensensorfaultOncetheoxygensensorfails,theelectronicfuelinjectionsystemwillenablethecomputershouldnotbetheoxygenconcentrationintheexhaustpipeoftheinformation,andthereforeshouldnotbeontheair-fuelratiofeedbackcontrol,theenginewillincreasefuelconsumptionandexhaustpollution,engineidlespeedinstability,lackoffire,suchasfault-surgesituation.Therefore,itisnecessarytotroubleshootinatimelymannerorreplaced.1,oxygensensorpoisoningOxygensensorpoisoningandareoftenmoredifficulttocontrolemergingasafault,inparticular,areoftentheuseofleadedpetrolcars,eventhenewoxygensensor,andcanonlybetheworkofthousandsofkilometers.Ifonlyminorleadpoisoning,andthenuseaboxofunleadedpetrol,willbeabletoeliminatethesurfaceofoxygensensorleadtotheresumptionofnormalwork.Butoftenbecauseofexcessiveexhausttemperature,whichleadintrusionintheirinternalandimpedethespreadofoxygenionstooxygensensorfailurecanonlybereplacedatthistime.Inaddition,theoxygensensorsiliconpoisoninghappenediscommon.Ingeneral,gasolineandlubricantscontainingsiliconcompoundsgeneratedbycombustionsilica,siliconrubbersealgasketimproperuseofsiliconeemittinggas,willcausetheoxygensensorfailure,andthereforewanttousegoodqualityfuelandlubricants.Righttochoosetherepairandinstallationofrubbergaskets,coatedonthesensornottorequiretheuseoffactoryandotherthantheanti-solvent,etc.2,carbondepositionNotbecauseofenginecombustion,inthecarbondepositionformedonthesurfaceofoxygensensor,oxygensensorortheinternalintothesediment,suchasoilordustwillimpedeorblocktheexternalairintotheoxygensensorinternaltooxygensensorsignaloutputinaccurate,ECUshouldnottimelycorrectair-fuelratio.Sootproduced,mainlyforincreasedfuelconsumption,emissionlevelsweresignificantlyincreased.Atthispoint,ifthesedimentremovalwillrestorenormalworking.3,oxygensensorceramicfragmentsCeramicoxygensensorhardwareandcrisp,withahardobjectbyknockingorwashingwithastrongaircurrentsblowingallitsfragmentationandpossiblefailure.Therefore,beparticularlycarefulwhenhandlingandfoundthatthetimelyreplacementofproblem.4,heaterresistancewireblownTheheating-typeoxygensensor,iftheresistanceheaterwireablation,itisdifficulttomakesensorstoreachnormaloperatingtemperatureandthelossofrole.5,oxygensensorbreakingofftheinternalcircuits.Four,automotiveoxygensensormethod1,oxygensensorheaterresistancecheckUnplugtheoxygensensorwiringharnessplug,useamultimeterresistancemeasurementfileintheoxygensensorheaterterminalaccess-chu-chuwithGroundbetweenaccessresistanceanditsresistanceto40-Ω(refertospecificmodel3specification).Suchasnotmeetingthestandard,shouldbethereplacementofoxygensensor.2,oxygensensorvoltagefeedbackmeasurementMeasurementofoxygensensorfeedbackvoltageshouldunplugtheoxygensensorwiringharnessplug,thecontrolcircuitmodels,thefeedbackfromtheoxygensensorvoltageoutputterminalonathinwireleads,andthenplugharnessplugswell,intheengineoperation,measuredfromthepinoutonthefeedbackvoltage(somemodelscanalsobeinnersocketfaultdetectionbyavoltageofoxygensensorfeedback,suchastheproductionofToyotacarscanbeaseriesoffaultdetectionfromthesocketterminalOX1orOX2directlymeasuredoxygensensorfeedbackvoltage).Oxygensensorfeedbackonthetestvoltage,itisbesttousewithlow-range(typically2V)andhighimpedance(resistancegreaterthan10MΩ)multimeterpointertype.Detectionofspecificmethodsareasfollows:1)hotcarsenginetonormaloperatingtemperature(orafterthestart-upspeedof2500r/minrunning2min);2)willfileanegativevoltagemultimetertableTthenfaultdetectionwithinthesocketorthebatterynegativeelectrodeE1isfaultdetectiontableTthenthesocketjackOX1orOX2,orreceiveoxygensensorwiringharnessplugontheNo.|round;3)toallowtheenginetomaintainspeedaround2500r/minoperationvoltagemeteratthesametimecheckwhetherthepointerbackandforthbetween0-1Vswing,withanoteofvoltagemeterpointer10sthenumberofswing.Undernormalcircumstances,withthefeedbackcontrol,theoxygensensorfeedbackvoltagewillbe0.45Vatchangingupanddown,10sinthenumberoffeedbackvoltagechangesshouldnotbelessthan8times.Iflessthan8times,thenoxygensensorfeedbackcontrolsystemornotworkingproperlybecausethesurfaceofoxygensensorarepossiblethereiscarbondeposition,sothatlowersensitivity.Inthisregard,shouldbeallowedto2500r/minenginespeedoperationofabout2min,toclearthesurfaceofthecarbondepositionoxygensensor,andthencheckthefeedbackvoltage.Iftheremovalofcarbondepositionmaychangeafterthevoltagemeterpointerisstillslow,thenoxygensensordamaged,orhavecomputerfeedbackcontrolcircuitfault.4)checkwhetherthedamagedoxygensensorUnplugtheoxygensensorwiringharnessplug,sothatoxygensensorisnolongerconnectedwiththecomputer,feedbackcontrolsystemisinastateofopen-loopcontrol.ThemultimetervoltagepentablefileisdirectlyrelatedtooxygensensorfeedbackvoltageoutputterminalconnectedtothenegativeformofgoodGroundpen.Measurementofengineoperationatthefeedbackvoltage,thefirstintakepipewastornoffandthenupatthemandatorycrankcaseventilationhosevacuumtubeorotherartificiallydilutethemixturetoform,atthesametimewatchvoltagemeter,thepointershouldbedroppedreadings.Wastornoffandthenconnectedtothepipeline,andthenunplugthewatertemperaturesensorconnector,a8K4-Ωinplaceoftheresistancetemperaturesensor,theformationofartificiallydensemixture,atthesametimewatchvoltagemeter,theindicatorreadingshouldbeincreased.Canalsobeused,orasuddenreleasetheacceleratorpedaldownapproachtochangetheconcentrationofthemixture,insuddenpedaldowntoaccelerate,themixture变浓,feedbackvoltageshouldbeincreased;suddenreleasewhentheacceleratorpedal,4mixedgas-thinning,feedbackvoltageshouldbedecreased.Iftheoxygensensorfeedbackvoltagewithouttheabovechangesshowthattheoxygensensorhasbeendamaged.Inaddition,thetitaniumdioxide-typeoxygensensorusingtheabovemethodatthetime,ifagoodoxygensensoroutputvoltageto2.5Vasthecentershouldbeupanddownfluctuations.Otherwise,thesensorcanberemovedandexposedtotheair,coolingtheresistancevalueafterthemeasurement.Ifalargeresistancevaluethatsensorisok,orshouldreplacethesensor5).oxygensensortocheckthecolorappearanceRemovedfromtheexhaustpipeonoxygensensors,sensorstocheckwhethertheshelltoplugupthevents,ceramiccorewhetherornotbroken.Ifdamaged,replacetheoxygensensorshouldbeBy.observingthetoppartoftheoxygensensorcanalsodeterminethecolorbreakdown:lightgraytop:Thisisthenormalcoloroftheoxygensensor;②whitetop:pollutionfromsilicon,oxygensensormustbereplacedatthistime;③browntop:pollutionbylead,ifserious,wemustreplacetheoxygensensor;④blacktop:causedbycarbondeposition,carbondepositionintheexclusionofenginefailure,thegeneraloxygensensorcanautomaticallyclearuptheaccumulatedcarbon.Conclusion:forenergyconservationandthepreventionofpollutionfrommotorvehicles,mostdevelopedcountriesintheWestaerobicsensorsinstalledonmycarisloadedoxygensensormustbeused.China'sautomobileindustrywithforeigncountries,oneofthemaingap,butalsoinautomotivesensors.Therefore,wecancometopromotetheuseofoxygensensorisveryoptimisticabouttheprospects.5汽车氧传感器的常有故障及检查汽车行业是目前在国际上应用传感器最大的市场之一,而氧传感器申报的专利数,居汽车传感器的首位。氧传感器装在汽车排气管道内，用它来检测废气口的氧含量。所以可依照氧传感器所获取的信号，把它反响到控制系统，来微调燃料的发射量，使A/F控制在最正确状态，既大大地降低了排污量，又节约了能源。目前，实质应用的氧传感器有氧化锆式氧传感器和氧化钛式氧传感器两种。而常有的氧传感器又有单引线、双引线和三根引线之分，；单引线的为氧化锆式氧传感器；双引线的为氧化钛式氧传感器；三根引线的为加热型氧化锆式氧传感器，原则上三种引线方式的氧传感器是不能够取代使用的。其中应用最多的是氧化锆式氧传感器。一、氧化锆式氧传感器的构造在使用三元催化变换器以减少排气污染的发动机上，氧传感器是必不能少的元件。氧传感器位于排气管的第一节，在催化转变器的前面。氧传感器有个二氧化锆（一种陶瓷）制造的元件，其里外都镀有一层很薄的白金。陶瓷化锆体在一端用镀薄铂层来封闭。后者被插到保护套中，并安装在一个金属体内。保护套起到进一步保护作用并使传感器得以安装到排气歧管上。陶瓷体外面裸露在排气中，而内部与环境大气相通。这个元件低温时有很高的电阻，所以温度低时不同样意电流经过。但高温时，由于空气中和废气中氧的浓度差异，氧离子却能经过这个元件。这就产生了电位差，白金将其放大。这样，空燃比低于理论空燃比（较浓）时，在氧传感器元件内（废气）外（大气）之间有较大的氧气浓度差。于是，传感器产生一相对较强的电压（约翰逊伏）。另一方面，若是混杂气稀，大气和废气之间氧浓度差很小，传感器也就只产生一相对较弱的电压（凑近0伏）。由于混杂气的空燃比一旦偏离理论空燃比，三元催化剂对CO、HC和NOX的净化能力将急剧下降，故在排气管中安装氧传感器，用以检测排气中氧的浓度，并向ECU发出反响信号，再由ECU控制喷油器喷油量的增减，从而将混杂气的空燃比控制在理论值周边。二、汽车氧传感器的工作原理氧传感器安装在排气歧管上，它能够检测废气中的氧气浓度，据此计算空燃比，并将结果传达到ECU。比方：1、废气中氧气浓度高当废气中氧气的百分比很大时，ECU将据此判断空燃比大，即混杂气很稀。2、废气中氧气浓度低当废气中氧气的百分比很小时，ECU将据此判断空燃比小，即混杂气很浓。温度高于300℃时，所采用的陶瓷资料，用作氧化铁的导体。在此条件下，若是传感器两侧氧的百分比含量不同样，就会在两端产生电压变化。两种环境（空气侧和排气侧）中不同样含氧量的测量值的这种变化告诉ECU，在排气中节余的氧含量，对保证燃烧有害废气生成是不合适的百分比。陶瓷资料在低于300℃温度时是非线性的，所以传感器不输送适用信号。ECU有一个特别功能，即在暧机时（开环运转）停止对混杂气的调整。传感器装有加热元件以赶忙达到工作温度。当电流流过加热元件时，它缩短了使陶瓷成为铁的导体的时间，而且使得传感器能够装在排气管较后的部位。6在三元催化净化器中，ECU利用来自氧传感器的数据，调治空燃比，但其方法EFI装置各标准化油器多稀有些不同样。在EFI装置中，EFI的ECU经过增减从喷油喷入气缸的燃油量，调治空燃比。若是ECU从氧传感器检测到混杂气太浓，就会逐渐减少燃油发射量，于是混杂气就变稀了。实质空燃比所以变得比理论空燃比大些（稀些）。发生这种情况时，ECU经过氧传感器测出这个事实，就会开始逐渐增加发射量。这样，空燃比就会娈得低些（浓些）直到低于理论空燃比。于是，这样循环屡次，ECU主浊以这种方式，不断地增减空燃比，使实质空燃比凑近理论空燃比。在使用化油器的装置中，是用调治进入进气口的空襟怀调治空燃比。混杂气平时保持略浓理论空燃比。ECU内氧传感器不断获取空燃比的信息，并要据实质空燃比控制EBCU（电控进气阀）调治进入化油器进气口的空襟怀。若是混杂气太浓，就赞同很多空气进入，使其变稀：若是混杂气太稀，就赞同较少空气进入，使其变浓些。三、汽车氧传感器的常有故障氧传感器一旦出现故障，将使电子燃油发射系统的电脑不能够获取排气管中氧浓度的信息，所以不能够对空燃比进行反响控制，会使发动机油耗和排气污染增加，发动机出现怠速不稳、缺火、喘振等故障现象。所以，必定及时地消除故障或更换。1、氧传感器中毒氧传感器中毒是经常出现的且较难防治的一种故障，特别是经常使用含铅汽油的汽车，即即是新的氧传感器，也只能工作几千公里。若是可是略微的铅中毒，接着使用一箱不含铅的汽油，就能除掉氧传感器表面的铅，使其恢复正常工作。但经常由于过高的排气温度，而使铅侵入其内部，阻拦了氧离子的扩散，使氧传感器无效，这时就只能更换了。别的，氧传感器发生硅中毒也是常有的事。一般来说，汽油和润滑油中含有的硅化合物燃烧后生成的二氧化硅，硅橡胶密封垫圈使用不当发散出的有机硅气体，都会使氧传感器无效，所以要使用质量好的燃油和润滑油。维修时要正确选用和安装橡胶垫圈，不要在传感器上涂敷制造厂规定使用以外的溶剂和防粘剂等2、积碳由于发动机燃烧不好，在氧传感器表面形成积碳，或氧传感器内部进入了油污或尘埃等聚积物，会阻拦或拥堵外面空气进入氧传感器内部，使氧传感器输出的信号失准，ECU不能够及时地修正空燃比。产生积碳，主要表现为油耗上升，排放浓度明显增加。此时，若将聚积物除掉，就会恢复正常工作。3、氧传感器陶瓷碎裂氧传感器的陶瓷