汽車專業(yè)畢業(yè)設計外文翻譯VIP

附錄：英漢比較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變濃,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汽車氧傳感器的常有故障及檢查汽車行業(yè)是目前在國際上應用傳感器最大的市場之一,而氧傳感器申報的專利數,居汽車傳感器的首位。氧傳感器裝在汽車排氣管道內，用它來檢測廢氣口的氧含量。所以可依照氧傳感器所獲取的信號，把它反響到控制系統(tǒng)，來微調燃料的發(fā)射量，使A/F控制在最正確狀態(tài)，既大大地降低了排污量，又節(jié)約了能源。目前，實質應用的氧傳感器有氧化鋯式氧傳感器和氧化鈦式氧傳感器兩種。而常有的氧傳感器又有單引線、雙引線和三根引線之分，；單引線的為氧化鋯式氧傳感器；雙引線的為氧化鈦式氧傳感器；三根引線的為加熱型氧化鋯式氧傳感器，原則上三種引線方式的氧傳感器是不能夠取代使用的。其中應用最多的是氧化鋯式氧傳感器。一、氧化鋯式氧傳感器的構造在使用三元催化變換器以減少排氣污染的發(fā)動機上，氧傳感器是必不能少的元件。氧傳感器位于排氣管的第一節(jié)，在催化轉變器的前面。氧傳感器有個二氧化鋯（一種陶瓷）制造的元件，其里外都鍍有一層很薄的白金。陶瓷化鋯體在一端用鍍薄鉑層來封閉。后者被插到保護套中，并安裝在一個金屬體內。保護套起到進一步保護作用并使傳感器得以安裝到排氣歧管上。陶瓷體外面裸露在排氣中，而內部與環(huán)境大氣相通。這個元件低溫時有很高的電阻，所以溫度低時不同樣意電流經過。但高溫時，由于空氣中和廢氣中氧的濃度差異，氧離子卻能經過這個元件。這就產生了電位差，白金將其放大。這樣，空燃比低于理論空燃比（較濃）時，在氧傳感器元件內（廢氣）外（大氣）之間有較大的氧氣濃度差。于是，傳感器產生一相對較強的電壓（約翰遜伏）。另一方面，若是混雜氣稀，大氣和廢氣之間氧濃度差很小，傳感器也就只產生一相對較弱的電壓（湊近0伏）。由于混雜氣的空燃比一旦偏離理論空燃比，三元催化劑對CO、HC和NOX的凈化能力將急劇下降，故在排氣管中安裝氧傳感器，用以檢測排氣中氧的濃度，并向ECU發(fā)出反響信號，再由ECU控制噴油器噴油量的增減，從而將混雜氣的空燃比控制在理論值周邊。二、汽車氧傳感器的工作原理氧傳感器安裝在排氣歧管上，它能夠檢測廢氣中的氧氣濃度，據此計算空燃比，并將結果傳達到ECU。比方：1、廢氣中氧氣濃度高當廢氣中氧氣的百分比很大時，ECU將據此判斷空燃比大，即混雜氣很稀。2、廢氣中氧氣濃度低當廢氣中氧氣的百分比很小時，ECU將據此判斷空燃比小，即混雜氣很濃。溫度高于300℃時，所采用的陶瓷資料，用作氧化鐵的導體。在此條件下，若是傳感器兩側氧的百分比含量不同樣，就會在兩端產生電壓變化。兩種環(huán)境（空氣側和排氣側）中不同樣含氧量的測量值的這種變化告訴ECU，在排氣中節(jié)余的氧含量，對保證燃燒有害廢氣生成是不合適的百分比。陶瓷資料在低于300℃溫度時是非線性的，所以傳感器不輸送適用信號。ECU有一個特別功能，即在曖機時（開環(huán)運轉）停止對混雜氣的調整。傳感器裝有加熱元件以趕忙達到工作溫度。當電流流過加熱元件時，它縮短了使陶瓷成為鐵的導體的時間，而且使得傳感器能夠裝在排氣管較后的部位。6在三元催化凈化器中，ECU利用來自氧傳感器的數據，調治空燃比，但其方法EFI裝置各標準化油器多稀有些不同樣。在EFI裝置中，EFI的ECU經過增減從噴油噴入氣缸的燃油量，調治空燃比。若是ECU從氧傳感器檢測到混雜氣太濃，就會逐漸減少燃油發(fā)射量，于是混雜氣就變稀了。實質空燃比所以變得比理論空燃比大些（稀些）。發(fā)生這種情況時，ECU經過氧傳感器測出這個事實，就會開始逐漸增加發(fā)射量。這樣，空燃比就會孌得低些（濃些）直到低于理論空燃比。于是，這樣循環(huán)屢次，ECU主濁以這種方式，不斷地增減空燃比，使實質空燃比湊近理論空燃比。在使用化油器的裝置中，是用調治進入進氣口的空襟懷調治空燃比?；祀s氣平時保持略濃理論空燃比。ECU內氧傳感器不斷獲取空燃比的信息，并要據實質空燃比控制EBCU（電控進氣閥）調治進入化油器進氣口的空襟懷。若是混雜氣太濃，就贊同很多空氣進入，使其變?。喝羰腔祀s氣太稀，就贊同較少空氣進入，使其變濃些。三、汽車氧傳感器的常有故障氧傳感器一旦出現故障，將使電子燃油發(fā)射系統(tǒng)的電腦不能夠獲取排氣管中氧濃度的信息，所以不能夠對空燃比進行反響控制，會使發(fā)動機油耗和排氣污染增加，發(fā)動機出現怠速不穩(wěn)、缺火、喘振等故障現象。所以，必定及時地消除故障或更換。1、氧傳感器中毒氧傳感器中毒是經常出現的且較難防治的一種故障，特別是經常使用含鉛汽油的汽車，即即是新的氧傳感器，也只能工作幾千公里。若是可是略微的鉛中毒，接著使用一箱不含鉛的汽油，就能除掉氧傳感器表面的鉛，使其恢復正常工作。但經常由于過高的排氣溫度，而使鉛侵入其內部，阻攔了氧離子的擴散，使氧傳感器無效，這時就只能更換了。別的，氧傳感器發(fā)生硅中毒也是常有的事。一般來說，汽油和潤滑油中含有的硅化合物燃燒后生成的二氧化硅，硅橡膠密封墊圈使用不當發(fā)散出的有機硅氣體，都會使氧傳感器無效，所以要使用質量好的燃油和潤滑油。維修時要正確選用和安裝橡膠墊圈，不要在傳感器上涂敷制造廠規(guī)定使用以外的溶劑和防粘劑等2、積碳由于發(fā)動機燃燒不好，在氧傳感器表面形成積碳，或氧傳感器內部進入了油污或塵埃等聚積物，會阻攔或擁堵外面空氣進入氧傳感器內部，使氧傳感器輸出的信號失準，ECU不能夠及時地修正空燃比。產生積碳，主要表現為油耗上升，排放濃度明顯增加。此時，若將聚積物除掉，就會恢復正常工作。3、氧傳感器陶瓷碎裂氧傳感器的陶瓷