中英文對照外文翻譯文獻(文檔含英文原文和中文翻譯)Theantilockbrakingsystem(ABS)analysisAbstract:Automobileantilockbrakingtechnologyisamaturetechnology.Equippedwithanantilocksystem(ABS)ofthevehicleundervariousdrivingconditionsespeciallywhenbraking,emergencybraking,cannotonlyutilizethepotentialofadhesionbetweentireandroadsurface,improvetheantislidingstabilityoftheridingdirection,keepthesteeringoperation,butalsocangivefullplaytothebrakingefficiency,shortenbrakingdistance,improvesafetythispapermainlyintroducestheperformanceofvehicleantilockbrakingsystemofautomobilewheel(ABS)analysisofthedefinition,structureandworkingprinciple,compositionandprincipleoftheelectroniccontrolpartandABSsystem,wheelspeedsensor,hydrauliccontrolcomponentsandprincipleofdevice.Itintroducestheantilocksystem(ABS)faultlightintheABS,ABSknowtheuseandmaintenanceof.Bythewheelantilockbrakingsystem(ABS)basedtointroduceitsworkingprinciple,theanalysisoftheworkingprincipleofABScontroldeviceisintroduced.Keywords:ABS;system;composition;principle;controlOne、wheelantilockbrakingsystem(ABS)1.1wheelantilockbrakingsystem(ABS)technologyisintroducedInearlytwentiethCentury,peoplebegantostudytheantilockbrakingtechnology.Begantoapplytotheaircraftandrailway,untilthelate50's,ABStechnologybegantobeusedinthecar.Thecoreideaistoavoidmakingthesameasthepowerswitch,thehydraulicsystempowercontrolinzeroorthebiggest,butaccordingtothespeedofthewheel,tocontrolthehydraulicpressure,sothatthebrakingperformancetogetthemaximumimprovement.First,awheelspeedsensorismeasuredwithawheeloradriveshafttorotatethetoothnumberofthesensinggear,andthefrequencyandthewheelspeedareproportionaltotheACsignal.TheACsignalofthewheelspeedsensorisfedintoanelectroniccontroller.Theelectroniccontrollercalculatesthespeedofthewheel,thespeedofthewheel,thespeedofthewheel,andthespeedofthevehicle.Thepressureregulatorpumpinstalledinthebrakemasterpumpandbrakesystem,receivecontrollerinstructions,bythepressureregulatingsolenoidvalvetocontrolthebrakingpressureincreaseordecreasethedevice,therebyregulatingthebrakingtorque,andmakethegroundadhesionstatusofthewheelsarelockedtopreventbrake.TheelectroniccontrolleralsocontrolstheothercomponentsoftheABS.Whenthecomponentsareintrouble,thecontrollermakesthealarmlamplight,andmakesthewholesystemstopworking.1.2wheelantilockbrakingsystem(ABS)classificationABSaccordingtothetransmissionmediumofthebrakesystem,canbedividedintotheairpressuresystem,gasliquidsystemandhydraulicsystem.Airpressuresystemismainlyusedforheavydutytruckandtrailer,thecompressedairgeneratedbytheenginedirectlycontrolthepressureofthepump.Gascapsystemisgenerallyusedforlargeandmediumsizedvehicles,inthefrontandrearaxleoftheoriginalbrakepipeineachoftheaircompressor,throughthecontrolofthepowergaschamberoftheinputpressuretoindirectlycontrolthehydrauliccylinderoutput.Hydraulicsystemforcars,vansandlighttrucks,systemincreasedabraketransmissionmediumindependentsupplydevice,suchastributariesmotorandrecyclepump.ABSaccordingtothenumberofcontrolchannelsandthenumberofsensors,canbedividedintosinglechannel,dualchannel,threechannelandfourchanneltype.Accordingtothecontrolmode,ABScanbedividedintomechanicalandelectronictype.DuetomechanicalABScontrolaccuracy,responseisslow,cannotguaranteetheemergencybrakewheelisnotlocked,hasbasicallybeenreplacedbyelectronicABS.Accordingtothearrangementofthepressureregulator,theABSisdividedintotheintegraltypeandtheseparationtype.Theintegraltype,whichismadeintoapressureregulatorandabrakemastercylinder,iscalledaseparationtypeofindependentbrakepressureregulatorandanindependentbrakemastercylinder.Two、wheelantilockbrakingsystem(ABS)compositionandprinciple2.1wheelantilockbrakingsystem(ABS)structureWhenthecarisnormal,thebrakeshoe10andthefrictionplate9inthespring13,andfixedonthewheelhubbrakedrum8tomaintainacertaingap,sothatthebrakedrumcanrotatewiththewheels.Wantstomakeamovingcartosloworstop,aslongasthedrivertosteponbrakepedal1,youcanmakethebodyofthebrakingenergythroughapushrod2andbrakemastercylinderpiston34,themastercylinderbrakefluidpressureintothebrakewheelcylinder6,andthroughtwowheelcylinderpiston7topromotethetwobrakeshoes10togetherwithfrictionplate9aroundthebranchunderwritingturned12,thefrictionplateoutercirclefacepressureinthebrakedrum8ofthesurfaceoftheinnercircle.Inthisway,thebrakeshoefrictionplateisfixedtotherotatingdrumofthebrakedrumandthefrictiontorqueisMu,anditsdirectionisoppositetotherotationdirectionofthewheel.Brakedrumtothebraketorquetransmittedtothewheels,duetothewheelsandtheroadsurfaceadhesion,wheelontheroadsurface.Aforwardedgeforce,brakebrakingforceFu.Atthesametime,theroadalsogivesthewheelabackwardreaction,thatis,theroadsystempowerFb,whichistoforcethecartoslowdownwhenthebrakeuntiltheparkingbrakeforce.Thegreatertheroadbrakingforce,thegreaterthecartoreducethespeed.Whenthedriverreleasesthebrakepedal,Backtothespring13isabouttobrakeshoesbackinplace,theoutercircleofthefrictionplateandtheinnercircleofthebrakedrumtoresumetheoriginalgap,frictiontorqueMuandbrakingforceFbtolift,thebrakefunctionisalsoterminated.Itisnotdifficulttoseethattheroadtostoptheroadfromthecar'sdrivingFbnotonlydependsonthebrakeforceFusize,butalsobythetireandroadadhesionconditions.Thatis,thecarbrakesystemonlyhasasufficientbrakebrakeforceFu,whiletheroadandcanprovidealargeF1,togetalargerroadbrakingforceFb.2.2workingprocessofbrakesystem:1、Parkingbrake.Carparking,manipulationhandbrakevalve3,releasingparkingbrakethree-waypipe6andaquickreleasevalveinthecompressedair,thespringenergystoragetyperearbrakeairchamberinthespringrelease,andpromotethereardrumbrakeshoeopen,frictionplateistightlypressedinthebrakedrumwitharoundface,parkingbrake.Inthebrake,thebrakethreethroughthetubeinthecompressedairhasbeenlost,therearestillparkingbrake.2、Toliftparkingbrake.Starttheengine,drivenbyaircompressoroperation,thebrakesystemairsupplypipelineandtwostoragecylinderwithcompressedair,compressedairpressurecanbethebarometer12toinstructions.Atthispointintheparkingbrakesupplylineinthequickreleasevalve4andtheairpressurealarmswitch5noairpressure,thealarmswitchtocontrolthealarmandthealarmlights,indicatingthecarisintheparkingbrakestate.Manipulationofthehandbrakevalve3toremovethebrakeposition,whenairpressureislower,thepressurewarninglampstilllight,saidbrakepressureisinsufficient;enoughairpressurebrake,parkingbrakegaspipelinethroughthequickreleasevalve4andthree-waypipejointsothattheparkingbrakeairchamberairsupplying,rearwheelbrakeairchamberstoragecompressionspringtherearbrakehoofpieceisreturned,rearwheelbrakeisinanonbrakestate,pressurealarmlights,carbrakepressureenough,youcanstart.3、Drivingbrake.Drivinginthebrakesystemairsupplypipelinepressureenough,setfootdrivingbrakefootbrakepedal,makeastraightfootbrakevalve2action,compressedairthroughthefour-way21fortothefrontbrakechamberjoint,beforethebrakewheel,thistimebrakelampswitch22isswitchedon,thebrakelights;compressedairproportionbyasenseoftheloadstoragevalve8andathree-waypipejoint6todonorofairchamber,therearwheelbrake,wheninstalledintheloadsensingproportionalvalverearbrakelampswitchispowered,thebrakelightbright.Thevehiclebrakingstrengthiscontrolledbythepedaltypebrakevalve,thebrakepedalstrokeisstrong,andthebrakepedaltravelissmallandweak.Wheninsufficientairpressureinthebrakesystem,installedinthewetstoragecylinder16onthelowpressurealarmswitchisturnedon,lowpressurealarmlightsandsirens,saidbrakepressureisinsufficient.4、Thedrivinghandbrake.Whenthefootbrakefailureornoairpressure,cancontrolthehandbrakevalvetothebrakeposition,canmaketherearwheelbrake.5、Thenopressurereleasetheparkingbrake.Thecarparkedinalongtime,maybeinanonpressurestate.Atthistimethecarparkingbrake.Theenginedoesnotstart,youwanttodragthecaraway,canbeusedtorotatethetworearwheelbrakespringbrakeairchamberoftheliftingofthebrakebolts,liftrearparkingbrake.Torecovertheparkingbrake,tocyclethebolt.2.3wheelantilockbrakingsystem(ABS)controlprincipleNowthepopularityofthecarontheABSisbasicallyanintegratedcontrolofelectrohydraulic.Andthatistomakethemechanicaldevice,thecontroldevicetobecometheelectroniccontrol.Thegeneralprincipleistodetectthewheelbythewheelspeedsensor,andthenthewheelspeedsensortomeasurethespeedofthesignalpassedthroughtheamplificationoftheECUcar(someoftheABScomputerisintegratedwiththeenginemanagementcomputerandsoon).Thenthecomputerthroughthesensormeasurementdatatodeterminewhetherthewheellocking,ifthewheelisnotfunctioningproperly,maybelockedorhasbeenlocking)thenacomputercanimmediatelyissuedadirectivetothesolenoidvalve,electromagneticvalveinavacuumstate,soastoachievebrakingforceisreduced,untilthelockinglift,ifatthistimethedriverstillvigorouslybrake,sotheABStoliftcontrolwheelwillreturntothelockedstate,sotheABSagainaccesstheknowlockonceagaintoremove.ThisiswhywearedrivingtheABScartobrakethebrakepedalwillproduceastrongjitter,whichistheABSofthethreesolenoidvalveinthework,thehydrauliccircuitandsometimesthepressurefromtimetotime,sothebrakepedalpulsejitterphenomenon.ThecontrolofABScanbemoreaccurateandmoreactivebyelectronicdevices.ButeventheelectroniccontroloftheABSaccordingtothedifferenttypesofitsconfigurationalsohasalotof.Firstofallfromthehardwareconfigurationismainlydividedinto:1channel2sensor,2channel3sensor,3Channel4sensor,4channel1sensortype,four.Forthefirstway,itcanbesaidtobetheearliestandmostoriginalABScontrolmode.Alsoistoachievetheabovesaidcomputercontrolall,butwhetheritisinformationaccesschannels(sensors)orcontrolchannels(channels)areonlyone.Asdescribedabove,itisthemostdangerousforthebrakingoftherearwheelslockedfirst.Forvehicleemergencybrakingespeciallyonslipperysurfacesundertheemergencybrake,rearwheelisthemosteasytolock.Iftherearwheelsthanthefrontwheelslockedfirst,andthatatthispointthedriverandintentofthesteering,thecarwillbethedangerofskiddingflick.SoforthesinglechannelABSisofcoursetogiveprioritytotherearwheellock.SotheABSsensorisinstalledinthereardifferential,whichisusedtoperceptionoftherearwheelslocking,andsolenoidvalveinstalledontherearbrakehydraulicpipe,whichisusedtoliftthelockingcrisis.Becauseonlyasensorandanelectromagneticvalvetocontrolthewheelbrakingforce,socomputeronlyforoverallrearwheellocktodealwiththecrisis.Ifthefrictioncoefficientofthepavementisdifferent,thenthesystemwillbeverydifficulttoadjustthesizeofthebrakingforceautomatically.Forthe2Channel2sensorABS,thesituationwillbebetter.Butthishardwareconfigurationcanbedividedintotwosolutions.Thefirstsolutionisthetwosensorandtwochannelsareassignedtofrontandrearwheels.Thiscanonlypreventlockingwiththewholeofthefrontwheelsandcanpreventtherearwheelslocked,butforontheleftandrightwheelsrunningonthepavementwithdifferentfrictioncoefficientsispowerless;anotherisforXpipingmodesettings.Theso-calledXistomakethebrakehydraulicpipingdiagonaldistribution.Inotherwords,thehydraulic50%fromthetotalpumpoutoftheleftfrontwheelandtherightrearwheel,whiletheother50%areassignedtotherightfrontwheelandrearwheel.Theonlytwochannelsarefittedonthemainsideoftheleftandrightwheels.SothisABScaninthecaseofhardwarelimitedpartofthesolutionbeforeandafterthewheellockandaroundthewheellock.Butforchannel33sensorhardwareequipmentsituationwouldbealotbetter,thiskindofABSinfrontofusingtwochannelandtwosensor,usingachannelandasensor(rearcontrolDocumentaryChannelsinglesensordesign)intherear,soitcannotonlytoautomaticdistributionbeforeandaftertheoverallbrakingforce,butalsoindependentregulationofthefrontwheelbrakingforce.ButthisisnotthemostperfectABS.ThemostperfectABSiscurrentlythemostwidelyused4Channel4sensorABS.ThiskindofABSreallysatisfiestherequirementofthesystempoweradjustmentonthehardware.Sowhetheritisfrontwheellockedfirstorthefirstlockingrearcanregulateeffectively,andeventhefourwheelsofroadsurfacefrictioncoefficientaredifferent,ABScanalsoautomaticallyadjust,leteachwheelwon'tlock.Sothe4channelsoftheABSsystemandthesystemwithmorethanoneadditionalfeaturecalledEBDelectronicsystempowerautomaticallocation.Infact,inthepurchaseofacar,ifthemanufacturerstopromotethiscarequippedwithEBDelectronicpowerdistribution,thenthecar'sABSforthe4Channel4sensordesign.Buteventhe4Channel4sensorABSaccordingtothedifferentperformanceofthesolenoidvalveisalsodifferent.ThisABSsolenoidvalveismainlydividedintotwotypes:oneisthe3solenoidvalve,theotheristhe2solenoidvalve.Alsoisthesolenoidvalve,therealizationofthefunctionisnotthesame.3solenoidvalvetothebrakehydrauliccontrolintothreekindsofstate,namely:thepressurestate,thestateofdecompressionandbalance.Andthe2bitofthesolenoidvalvecanonlybethebrakehydrauliccontrolinto:thestateandbalanceofthetwokindsofstate.Althoughtheperformanceofacompressionfunctionisnotthesameasthatofapressurefunction.The2isequippedwithasolenoidvalveABS,itcanonlyplaytheroleofpreventingthebrakelocking.Becauseitcanonlyreduceormaintainthebrakefluid,thatis,onlyafterthebrakepedaltothebrakepedal,hecanplayarole.Soevenifitisthe4sensor4channels,canonlyachievethepowerofEBDelectronicsystempowerautomaticallyassigned.AndforequippedwiththreeABSsolenoidvalve,fromthehardware,itmeetstheESPelectronicstabilitysystem,TCStractioncontrolsystemandEDLelectronicbrakingspeedrequirementsofthepoor.Thereasoniscalled3solenoidvalve,iscomparedwiththe2solenoidvalvetoincreasethepressurefunction.Thatis,evenifthedriverdidnotsteponthebrakepedal,thecomputercanalsoautomaticallycontrolasinglewheelbrake.Thenwhatgoodisit?Wefirstsimplyfromthefunctionofthebrake.Ifthecomputercanautomaticallycontroltheincreaseinhydraulic,thenwewillgetamoresecureperformanceinthehighspeedandstrongbraking.Becauseofthehightemperatureofthebrakesystem,thebrakesystemisveryhigh,andthebrakediscisveryhot.Theso-calledthermalattenuationisactuallyduetothebrakediscandbrakeshoeistoohightemperature,resultinginthesurfaceorlocalonthevergeofmelting,theengineeringstrengthisreduced,sothebrakeforcewillweaken.Thesamereason,whenweareataspeedof120,oreven160ofthespeedofthespeedis,iftheneedtospeedupthespeedofthebrakesystemto20oreventheloadisverylarge.Duetothedriver'shabitsistokeepthebrakepedaltoformthesamesocaliperbrakingforceisconstant,soastothelaterstagebrakeduetothehightemperaturebeginstodecay,thedriverisoftendifficulttofindtheweakeningofthebrakingforce,andsowillnotbeactivecontinuetoincreasebrakingpower.Sobecausethethreesolenoidvalveandcontrolofthebrakelinepressurefunction,soitcanautomaticallyincreasethebrakingforce,sothatthespeedofthebraketomaintainlinear,eventotheendofthebrakeandthermaldecay,canalsobeduetothebrakeforceisnotlineartothesafetyrisk.Butthisisjustthethreebitofthesolenoidvalveonthebrakeside,infact,thecontributionofthethreesolenoidvalveisfarmorethanthat.Itsbiggestroleistorealizethecomputerautomaticallytoasinglewheelbrake,sothatESPorEDLcanbeachieved.WeknowthatESPisaBOSCHdevelopmentofasetofelectronicstabilityprogram,toachievesuchanelectronicstability,wemusthavea4Channel4sensorsand3solenoidvalveisequippedwithhardware.ESPwasabletoletfrontwheeldrivecarreduceundersteer,drivereduceoversteer,becauseitcanonthesliprateexceedsacriticalvalueofthewheel(i.e.skiddingofthewheels)separatebraking,soastogetridoftheoutofcontrolofthesituation,allthesedonotneedhumanintervention,andisinaveryshortperiodoftimebycomputercontroltocomplete.Simply,theprincipleisthatthecomputerdetectsthespeedofeachwheelbymeansofthefourwheelspeedsensor,andthencalculatesthespeedofawheelbymeansofavehiclespeedsensorandasteeringanglesensor.Iftheactualspeedofthefourwheelsandthetheoreticalspeeddoesnotmatchthecomputerwilldeterminethewheelhastheriskofslippingoutofcontrol,thenECUwillimmediatelynotifythethreesolenoidvalvetothewheeltobrake,sohereturnedtonormalspeedundertherestrictionofbrakingforce.Sohecanimprovetheactivesafetyperformanceofthecartoagreatextent,makethecarhavebettertracking.ForEDL,itsworkingprincipleissimilartothatofESP.Isthewheelspeedsensordetectionofactivewheelspeedvalue,iftwoactivewheelspeeddifferenceinthenormalrange(throughthesteeringanglesensorjudgment,becauseinturndrivenwheelspeeddifferenceisnormal),sotheABSdoesnotwork;ifdetectedabouttwodrivingwheelspeeddifferenceistoolarge,thecomputerwilldeterminethehighrotationalspeedofthewheelisslipping,sointhreesolenoidvalveundertheactiontothespinofthewheelbrakingforcesappliedadditional,powercanbetransmittedtothenoskidwheelthereto,makethecarcanstillhavenormaltractioncontrol.Ofcourse,forthefourwheeldrivecarthiselectronicdifferentialbrakingismoreimportant,becauseitcanbethroughasinglewheeltoadjustthebrakingforcedistribution.Setcanmakethepoweronanyoneofthewheelsfromthe0%-100%regulation.Soitisnotrequiredtoincreasethecaseofotherhardwaredevicestoachievesuchanumberofderivatives.Thatistosaythe4Channel4sensorandequippedwiththree4bitsolenoidvalveABSiscurrentlythehighestmarketspecificationsABS,aslongastheprogramsupports,youcanachieveallthefunctionsmentionedabove汽車防抱死系統（ABS）的研究分析摘要：汽車制動車輪防抱死技術是一項比較成熟的技術。裝用車輪防抱死系統（ABS）的汽車在各種行駛條件下制動時，特別是緊急制動工況，不僅能較好利用輪胎與路面之間的潛在附著力，提高騎著抗滑的方向穩定性，保持轉向操作性，而且能充分發揮制動效能，縮短制動距離，提高整車的安全性能本文主要介紹汽車車輪防抱死系統（ABS）的定義、結構組成及工作原理分析，和ABS系統的電子控制部分的組成和原理，輪速傳感器，液壓控制裝置的組成和原理。還介紹了車輪防抱死系統（ABS）中的ABS的故障燈，ABS曉得使用和檢修。由車輪防抱死系統（ABS）的基礎來引出其工作原理，分析ABS工作原理的同時進行控制裝置的介紹。關鍵詞：ABS；系統；組成；原理；控制1、車輪防抱死系統（ABS）1.1車輪防抱死系統（ABS）的技術介紹早在20世紀初，人們就開始研究制動防抱死技術。開始應用于飛機和鐵路，直到50年代后期，ABS技術開始用于汽車。其核心思想始終是避免使制動力像開關一樣，只把液壓制動力控制在零或最大，而是根據車輪的減速情況，階段性地控制液壓，使制動性能得到最大限度的改善。首先由輪速傳感器測出與車輪或驅動軸共同旋轉地傳感齒輪的齒數，從而得到頻率與車輪轉速成正比的交流信號。輪速傳感器的交流信號送入電子控制器，電子控制器計算出車輪速度、滑移率和車輪的加、減速度，然后再由電子控制器對這些信號加以分析，給壓力調節器發出制動壓力控制指令。壓力調節器安裝在制動系統的制動總水泵與制動分泵之間，接受控制器的指令后，由壓力調節器中的電磁閥控制制動壓力的增加或減小，從而調節制動力矩，使之與地面附著狀況相適應防止制動車輪被抱死。電子控制器還對ABS的其他元件進行控制，當這些元件發生故障時，控制器令警報燈點亮，并使整個系統停止工作，恢復到常規制動方式。1.2車輪防抱死系統（ABS）的分類ABS根據制動系統的傳動介質，可分為氣壓系統、氣頂液系統和液壓系統。氣壓系統主要用于重型載重汽車及其掛車，由發動機產生的壓縮氣直接控制動力分泵的氣壓，不需在原有的系統中增加另外的部件，能較容易地獨立控制各車輪的制動力。氣頂液系統一般用于大中型汽車，在前后軸原有的制動管路中各裝一個空氣加壓器，通過控制動力氣室的輸入氣壓間接地控制液壓主缸的輸出液壓。液壓系統用于轎車、廂式車和輕型載重車，系統中增加了一套制動傳動介質的獨立供給裝置，如支流電動機和再循環油泵。ABS根據控制通道數量和傳感器數量，可分為單通道式、雙通道式、三通道式和四通道式。根據控制方式，ABS可分為機械式和電子式。由于機械式ABS控制精度差，反應速度慢，不能保證緊急制動時車輪不被抱死，已經基本被電子式ABS所取代。根據壓力調節器的布置，ABS分為整體式和分離式。將壓力調節器與制動總泵制成一體的稱整體式，具有獨立制動壓力調節器和獨立制動總泵的稱分離式。2、車輪防抱死系統（ABS）的組成與原理2.1車輪防抱死系統（ABS）的結構組成汽車正常行駛時,制動蹄10連同摩擦片9在彈簧13的拉力下，與固定在車輪輪轂上制動鼓8之間保持有一定的間隙，使制動鼓能隨車輪一同自由轉動。欲使行駛中的汽車減速或停車時，駕駛員只要踩下制動踏板1，就可使肌體的制動能源通過推桿2和制動主缸4中的活塞3，使主缸內的制動液加壓流入制動輪缸6，并通過兩個輪缸活塞7推動兩個制動蹄10連同摩擦片9繞支承銷12轉動，使摩擦片的外圓面壓緊在制動鼓8的內圓面上。這樣，固定不旋轉地制動蹄摩擦片就對旋轉著的制動鼓作用一個摩擦力矩Mu，其方向與車輪旋轉方向相反。制動鼓將該制動器制動力矩傳到車輪后，由于車輪與路面的附著作用，車輪對路面作用一個向前的周緣力，即制動器制動力Fu。同時，路面也給車輪一個向后的反作用力，即路面制動力Fb，這就是制動時迫使汽車減速行駛直至停車的外力。路面制動力愈大，汽車減速度也就愈大。當駕駛員松開制動踏板時，回位彈簧13即將制動蹄拉回原位，摩擦片的外圓面與制動鼓的內圓面之間恢復原有間隙，摩擦力矩Mu和制動力Fb解除，制動作用也就終止。綜上所述不難看出，阻止汽車行駛的路面制動力Fb不僅取決于制動器制動力Fu的大小，而且還受到輪胎與路面間附著條件的限制。也就是說，汽車制動系只有具備了足夠的制動器制動力Fu，同時路面又能提供大的附著力F1時，才能獲得較大的路面制動力Fb。2.2制動系統工作過程①駐車制動。汽車駐車時，操縱手制動閥3，放掉駐車制動三通管6和快放閥4中的壓縮空氣，使彈簧儲能式后制動氣室中的儲能彈簧釋放，推動后輪鼓式制動器制動蹄片張開，摩擦片緊壓在制動鼓的內圓面上，起駐車制動作用。在制動中，制動三通管中壓縮空氣已全部流失，仍有駐車制動。②解除駐車制動。起動發動機，帶動空氣壓縮機運轉，使制動系統供氣管路和兩個儲氣筒中充滿壓縮空氣，壓縮空氣的壓力可由氣壓表12來指示。此時接在駐車制動供氣管路中的快放閥4和氣壓警報開關5無氣壓，氣壓警報開關控制警報器發響和警報燈亮，指示汽車處于駐車制動狀態。操縱手制動閥3至解除制動位置，氣壓較低時，氣壓警報燈仍然燈亮，表示制動氣壓不足；制動氣壓足夠時，駐車制動供氣管路通過快放閥4和三通管接頭使駐車制動氣室供氣，壓縮后輪制動氣室儲能彈簧，使后輪制動蹄片回位，后輪制動即處于非制動狀態，氣壓警報燈熄滅，表示汽車制動氣壓足夠，可以起步。③行車制動。行車中在制動系統供氣管路氣壓足夠的情況下，踏下行車制動（腳制動）踏板，使直踏式制動閥2動作，壓縮空氣通過四通接頭21供至前制動氣室，使前輪制動，此時前制動燈開關22接通，制動燈亮；壓縮空氣按比例通過感載儲閥8和三通管接頭6供至后制動氣室，使后輪制動，此時裝在感載比例閥上的后制動燈開關9接通，制動燈亮。汽車制動強度是由直踏式制動閥通過踏板控制的，踏板行程大制動強；踏板行程小制動弱。當制動系統中氣壓不足時，裝在濕儲氣筒16上的低壓警報開關接通，低壓警報燈亮和警報器響，表示制動氣壓不足。④行車手制動。行車中腳制動失靈或無氣壓時，可以操縱手制動閥至制動位置，可使后輪制動。⑤無氣壓解除駐車制動。汽車長期停放，可能處于無氣壓狀態。此時汽車駐車制動。發動機不起動，想要將汽車拖走時，可用扳手旋轉兩個后輪的彈簧制動氣室的解除制動螺栓，解除后輪駐車制動。要想恢復駐車制動，要旋回這個螺栓。2.3車輪防抱死系統（ABS）的控制原理現在轎車上所普及的ABS基本上都是電液一體式控制的。也就是把機械的感應裝置，控制裝置全部變成了電子來控制?？偟脑砭褪峭ㄟ^車輪轉速傳感器來檢測車輪的運轉情況，然后把車輪轉速傳感器測得的轉速信號通過放大以后傳遞給ECU車載電腦（有些車的ABS電腦是跟發動機管理電腦等集成在一起的）。然后電腦通過傳感器測得的數據判斷車輪是否抱死，如果車輪運轉不正常（有可能抱死或已經抱死）那么電腦會立即發出指令給電磁閥，讓電磁閥處于減壓狀態，從而達到降低制動力的目的，直到抱死解除，如果此時駕駛員仍然在大力剎車，那么ABS解除控制后車輪又會回到抱死狀態，那么ABS再次接入知道抱死再次解除。這就是為什么我們在駕駛ABS車大力制動的時候剎車踏板會產生強烈的抖動，這就是ABS的三位電磁閥在工作，液壓油路時而增壓時而減壓，所以造成剎車踏板的脈沖抖動現象。通過電子設備接入以后ABS的控制能夠更加精確，而且更加主動。不過即便是電子控制的ABS根據其配置的不同種類也有很多。首先從硬件配置來說主要分為：1通道1傳感器式，2通道2傳感器式，3通道3傳感器式，4通道4傳感器式等四種。對于第一種方式，可以說是最早最原始的ABS的控制方式。同樣是實現上文說的電腦控制一切，但無論是信息獲取渠道（傳感器）還