.z.畢業(yè)論文附件材料目錄1英文文獻翻譯11.1Shiftgearbo*11.2變速箱的換擋方式12-.z.1英文文獻翻譯1.1Shiftgearbo*Classificationusuallygearbo*asfollows:ManualtransmissionThegeneralautomaticgearbo*/monautomatictransmissionwithtiptronicCVTsteplessgearbo*withgearbo*ofthe/CVTDualclutchgearbo*Sequentialgearbo*(1)manualgearbo*Manualtransmission,alsoknownasmanualgear,Englishnameismanualtransmission,referredtoasMT,whichpushtheshiftlevertochangegearsmeshingpositioninsidethetransmission,changingthetransmissionratio,soastoachievethepurposeofspeed.Stepontheclutch,canmovetheshiftlever.Theworkingprincipleofamanualgearbo*Themanualgearbo*isposedofdifferentgearratioofthegeargroup,itsbasicprincipleisthroughthegeargroupworkindifferent,torealizethetransformationofgearratio.Asthekeylinkforpowerdistribution,transmissionmusthavethepowerinputshaftandtheoutputshaftofthebigtwo,togetherconstitutethetransmissiongear,isamanualtransmissionisthemostbasicponent.Thepowerinputisconnectedwiththeclutchshaftclutchtransmission,fromthepowertodirectlythroughtheinputshafttothegroup,thegearsetisposedofdifferentdiametergear,gearpowertransmissioneffectofdifferentproportionreachedispletelydifferent,theusualshiftdrivingalsoreferstochangegearratio.Ne*t,letusthroughasimplemodeltotellyou,theprincipleofmanualgearbo*shift.Belowisasimplestructuralmodelof3a*is2speedgearbo*.Theinputshaft(green)isalsocalledthefirstshaft,connectedbyaclutchandengine,shaftandthegearisahardconnectedponents.Rediscalledtheintermediategearshaft.Enterthetwogearshaftandintermediateshaftisinconstantmeshstate,sowhentheinputshaftrotateswilldriveshaftrotation.Yellowistheoutputshaft,itisalsocalledthesecondshaftsandconnectedtothedriveshaft(onlyforrearwheeldrive,theprecursorisgenerallytwo),andthenthroughthedifferentialdrivevehicles.Whenthewheelrotatesthesamewithsplineshafttorotatetogether,atthistime,bluegearshaftcanoccuronthesplineshaftrelativefreerotation.Therefore,theenginestops,andthewheelisrotated,thebluegearandshaftinthestationarystate,andthesplineshaftwithwheels.Theprincipleandthereara*leofthebicycleflywheelissimilar.Bluegearandsplineshaftisposedofasleevetoconnect,sleevewithsplineshafttorotate,butalsocanbefreetoslideonthesplineshafttogear.Withthese,theshiftingprocessisverygoodunderstanding,whenconnectingsleeveandabluegear,enginepowerwillbetransmittedtotheoutputshaftthroughtheshaft,atthesametime,bluegearleftinfreerotation,butbecausethereisnoandsleeveengaged,soitdoesnotaffectthesplineshaft.Ifthesleevebetweenthetwobluegear,thegearbo*inneutralposition,thetwobluegearonthesplineshaftrotatefreely,withoutmutualinterference.Principleofaconventional5speedmanualgearbo*shiftisthesame,onlythegearbo*structureincreasedthenumberofsleeveandthegearsets,sothatithasmoregear.Butthereverseisbasedontheintermediateshaft(red)andtheoutputshaft(blue)isaddedbetweenageartoachieve.Duetotheincreaseofagear,thereversegearwillalwaysrotatetowardothergearintheoppositedirection.Thegearbecauseonlytochangegearrotationdirectionfunction,soitisalsocalledtheidler.5blocktwoshafttransmissionstructure,theinputshaftandthedrivinggearareintegratedintoawhole,simplifiesthestructureandsavesspaceInadditiontothetraditionalthreea*ismanualgearbo*,thewidespreaduseofcarsistwoa*ismanualtransmission,itsstructureandthethreeshaftofthegearbo*issimilar,onlytheinputshaftandintermediateshaftasashaft,thereforehastheadvantagesofsimplestructure,smallsizeadvantages,inaddition,italsohasthemiddlegeartransmissionhighefficiency,andlownoisecharacteristics,soitismoresuitabletobetheprecursorhomecargeneralcartransmissionform,iscurrentlythemostwidelyused,itsshortingsisnotsetupdirectgear,transmissionandfilethanthedesigncannotbetoohigh.Whiledriving,threeshaftgearbo*usedisstillthetraditional.Manualgearbo*ingeneral,isthroughthepushrodisconnectedorcabletocontroltheshift.Pushrodshiftcontrolconnection,moredirectbutvibrationwillbelarge;andthecabletypealthoughnovibration,buttheshiftisnotveryclear,itiseachtohavegoodandbad.Inadditiontoshiftthetwopuremechanicalcontrol,inaddition,andtheuseofelectronicshiftdeviceofmanualtransmission,whichcanbinethemeritsofpushandpulltheshiftbetweenthegood.Thiskindofgearbo*intheshiftwhenthegearshiftlever,shiftingtothecorrespondinggear,thetransmissionwillbemotordrivethecorrespondingforkcontrolsleeveandthegearisengaged,sothatthereisnogearisnotclear,buttheshiftschedulecanbecontrolledintheidealrange.So,agoodmanualtransmissionneedtohavewhatcharacteristic"Thefirsttransmissionmusthavegoodgearhandle,eachgearpositionclear,havereasonablehorizontalandverticalstroke,intotheblockresistanceissmallandwithsuction.Whatismoreimportantis,thegeartoothbetweenthanarrangementmustbereasonable.Becauseeachgearpositionthandistribution,directlyaffectthecohesionpowervehiclesmovinginasmooth,usuallyrequirealowgearcaneffectivelyaccelerate,highblocktoachievehighspeedandefficient,andthedistancebetweeneachblockshouldbeuniform,otherwisewillbeveryeasytocausethechannelingshiftwhenthecar.Analysisoftheadvantagesanddisadvantagesofmanualgearbo*AdvantagesObviously,whichissimpleinstructure,reliableperformance,manufacturingandmaintenancecostislow,andthetransmissionefficiencyishigh(theorywillbemorefuel-efficient),also,becauseitispuremechanicalcontrol,shiftreactionisfast,andcanbemoredirecte*pressionofdriver'sintention,andthereforemoredrivingpleasure,thesearetheadvantagesofmanualgearbo*.Butparedtoautomatictransmission,itsoperationisplicated,andfrustrationingearswitchwhentheobviousdisadvantageisirreparable.(2)automaticgearbo*AutomatictransmissionAT,thefullnameofAutoTransmission,whichisposedofhydraulictorqueconverter,posedofplanetarygearandhydrauliccontrolsystem,throughthehydraulictransmissionandgearbinationtoachievevariablespeedmoment.paredwiththemanualtransmission,automatictransmissionisverydifferentinstructureandusage.Themanualismainlyregulatedbydifferentgearbinationtochangegear,andtheautomatictransmissionisthroughthehydraulictransmissionandgearbinationtoachievethepurposeofchangingspeed.Hydraulictorqueconverterisoneofthemostcharacteristicoftheautomaticgearbo*parts,whichisposedofapump,turbineandguidewheelandotherponents,pumpwheelandturbineisabinationofwork,throughtheliquidpumpwheeldrivestheturbinetorotate,andthewheelbetweenthepumpandturbinewheelthroughthereactionbetweenthepumpwheelandturbineimplementationthespeeddifferenceandimplementationofvariabletorquefunction,thedriver,youonlyneedtodifferentintensityslamthepedal,thegearbo*canautomaticallystoplifting.Sincethetorqueconverterautomatictransmissiontorquerangeisnotbigenough,soinalaterseriesseveralrowsofplanetarygeartoimproveefficiency,thehydrauliccontrolsystemwillchangewiththeenginetomanipulatetheplanetarygear,soastorealizetheautomatictransmissiontorque.Inordertomeetavarietyofrunningprocessneeds(suchasparking,reversing),automatictransmissionalsohassomemanualshiftleverposition,likethePblock(Rblock(anchor),aftertheblock),blockN(neutral),D(forward),block.Fromtheperformancethatthemoregearautomaticgearbo*,thecarintheprocessofrunningmoresmoothly,accelerationisbetter,andmorefuel-efficient.Inadditiontoprovidingafortabledrivingfeeling,automatictransmissionalsohasinsurmountabledefects.Dynamicautomatictransmissionresponseisnotdirectly,whichmakesitinthe"drivingpleasure"slightlyshortage.Inaddition,becauseoftheuseofhydraulictransmission,theautomatictransmissiongearbo*transmissionpowerloss.TiptronicautomatictransmissionHandsappearedgearbo*isinordertoimprovetheautomaticgearbo*andoperatingeconomyandincreasethesetting,lettheoriginalputerautomaticshifttimebackintothehandsofdrivers.Atthesametime,ifinthecitytrafficin,oryoucanalwaysswitchbacktoautomatic.Atiptronicautomatictransmissionisactuallyautomaticgearbo*,firstappearedinaPorsche911,manualgearbo*electroniccontrolsystemthroughthesimulationoftheoperationofamanualgearbo*.Itappears,givingthedriveragreaterdegreeoffreedomintheoperation,canblockuptheblockingorshiftpaddlesonthesteeringwheeltochoosetheirowngearandshiftthetimingright,therebygreatlyimprovingthedrivingpleasure.(3)CTVnon-polartransmissionCVT(ContinuouslyVariableTransmission),directtranslationisacontinuouslyvariabletransmission,whichiscontinuouslyvariabletransmission.Weoftensay,justasitsnameimpliesisthatthereisnoclearandspecificfile,whichoperateonsimilarautomaticgearbo*,gearjumpprocessbuttheratiochangeisdifferentfromtheautomaticgearbo*,butacontinuous,sothepowertransmissioncontinuessmooth.CVTtransmissionsystem,thetraditionalgearbyapairofpulleysandasteelbeltisreplaced,eachblockisVstructureisposedoftwointervertebraldisk,engineshaftisconnectedthroughasmallpulley,steelbeltdrivepulley.Mysteryliesinthisspecialpulley:drivepulleystructuresCVTstrangeactivity,dividedintohalves,canbeclosetoorseparaterelative.Conedisccantightenoropenthethrusthydraulic,e*trusionsheetsteelchainsoastoadjusttheVslotwidth.Whentheconediscinsidemobiletightened,steelchaininthee*trusionconestocenteroutsideofthedirectionofmovement(centrifugaldirection),butmovingtothecenterofthecircle.Inthisway,steelchaindrivesthediscdiameterincreases,thetransmissionratioischanged.TheCVTgearbo*whataretheadvantages"1,becausethereisnogeneralautomatictransmissiongear,therewillbenoshiftprocessofautomatictransmission,shifttheresultingsenseoffrustrationwilldisappear,sothepoweroutputofCVTgearbo*islinear,inactualdrivingverysmooth.Theoryoftransmissionsystemof2CVT,thegearcanbeanunlimitednumberofgearset,morefreedom,thetraditionaltransmissiongearratio,speedratioandperformance,fuelconsumption,e*haustemissionsbalance,aremorelikelytoachieve.3,themechanicalefficiencyofCVTtransmission,theprovinceisoilyconsiderablybetterthantheautomatictransmissionmon,aftermanualgearbo*,fueleconomyismuchbetterthan.Sincetherearesomanyadvantages,whynotletallthecarsusingCVTgearbo*"Therearetwofactors:1,paredwiththetraditionalautomatictransmission,itscostishigh;andtheoperationisundeservedword,thehigherprobability.2,CVTgearbo*itselfstillhasitsshortings,isthetransmissionofthesteelbeltcanwithstandstrengthislimited,generallymorethan2.8Lcapacityorpowerabove280N?Misitslimit,butwealsoseethattherearemoreandmorecarssuchasAudi,orNissan,hasbrokenthelimit,believestriptheproblemwillbesolvedgradually.(4)dualclutchgearbo*Dualclutchgearbo*DCT,EnglishnameisDualClutchTransmission,becauseithastwoclutches,socalled"dualclutchtransmission".TechnologyintroducedDualclutchgearbo*binestheadvantagesofmanualtransmissionandautomatictransmission,notorqueconverter,insteadofusingtwosetsofclutch,throughtwosetsofclutchalternatelywork,toachieveseamlessshifteffect.Twoclutchesrespectivelycontroltheoddblockandevenblock,thatistosay,intheshiftbefore,DSGhadthene*tgearmeshing,aftershiftinginstruction,DSGquicklysendsinstructionstotheengine,theenginespeedincreases,thepreviousmeshinggearsquickly,whilethefirstgroupofclutchfullyliberalized,thepletionofarisetoblocktheactiontime,actionandsoon.Becausewithoutthetorqueconverter,sothepoweroftheenginecanbefullyplayedout,whilethetwoclutchalternatelywork,shifttimemaking,dynamicfaultenginemaybeverylimited.Asthedriveristhefeelingthatwearethemostdirect,switchgearactionveryquicklyandsmoothly,dynamictransmissionprocessofalmostuninterrupted,vehicledynamicperformancecanbefullyplay.paredwiththetraditionalautomatictransmissionwithtorqueconverter,theDSGshiftmoredirectly,thepowerlossissmaller,sothefuelconsumptioncanbereducedbymorethan10%.DeficienciesHowever,withthetraditionalautomatictransmissionratio,DSGalsohassomeinherentdisadvantages,firstlyitisbecausethereisnousehydraulictorqueconverter,norrealizemanualtransmission"linkage"action,soforthesmall-displacementengine,lowspeedtorquecharacteristicisnotenoughtobepletelye*posed;secondly,becausetheDSGtransmissionusingputercontrol,belongingtoanintelligenttransmission,itneedstosendelectronicsignalstotheengineblockintheprocessoffallingintheL/,theengineafterreply,andtheenginetobepletedwithL/reductiongear.Alargenumberofelectronicponents,butalsoincreasestheprobabilityofitsfailure.ThedualclutchmonwithVolkswagen'sDSG,FordPowershift,MitsubishiSSTandPorschePDK.(5)sequentialgearbo*Sequentialgearbo*(AMT)isimprovedonthetraditionalmanualgeartransmissionbasedon;itbineshydromechatronicsautomatictransmissionhastheadvantagesofbothATandMT;AMThastheadvantagesofautomatictransmissionmonautomatictransmission,andtheretentionefficiencyoftheoriginalmanualtransmissiongeartransmission,thehighcostoflow,simplestructure,easymanufacture.Itisthereforminthepresentmanualtransmission,retainedmostoftheoriginalassembly,onlytochangetheshiftlevermanualoperatingsystempart,theproductionofsuccession,totransformtheinputcostsless,isveryeasytobemanufacturerstoaccept.Thedriverthroughtheacceleratorpedalandjoysticktotheelectroniccontrolunit(ECU)controlsignaltransmission;electroniccontrolunitcollectstheenginespeedsensor,thespeedsensorsignal,thetimetomastertherunningstateofthevehicle;electroniccontrolunit(ECU)basedonthebestprogramaccordingtothesesignalsstoredtherein,optimalshiftingrules,clutchfuzzycontrolrulesengineoil,adaptivecontrollaw,actionandtemporalseparationoftheengine,clutchandtransmissionshiftbinding,thethreetoachievethebestmatching.Inordertoobtainthee*cellentfueleconomyandpowerperformanceandabilitytosmoothstartandrapidshift,inordertoachievethedesiredresults.ButtheAMTtransmissionisnotperfect,thebiggestdisadvantageofAMTgearbo*isshiftingfortispoor,andgeneratepowerinterruptionintheprocessofshifting,theshiftintheprocessofspeedperformanceisnotgood.AMTmechanicalgearbo*,itsbasicstructureandconventionalmanualgearbo*consistent,generallyonlyoneinputshaftandanoutputshaft(RWDusuallyamiddleshaft),whichgenerallyistheinputshaft5forwardgearandoutputshaftgearisinconstantmeshstate,whereintheoutputshaftofthe1gearandareversegear,2blockandthe3block,4blockand5blockweresharedbythethreeshiftfork.Themechanismoftwoadjacentgearwithashiftingmechanism,whentheshiftaction,forkneedonceuponageardefect,throughneutraltothene*tgeargearmeshing,duetothreeactionsistheorder,evenifeachactionwillbethetimetoaminimum,isstillverydifficulttoobtaintheshiftspeedfastenough."Independentinnovationshiftfork"TheISRgearbo*hasauniquestructure,thegeararrangementitisdifferentwiththetraditionalAMTgearbo*,alsodifferentfromthedualclutchgearbo*.Theuseoffourindependentshiftfork,twostallsadjacenttothegearshiftforkisposedofdifferentcontrol.Fourindependentforkrespectivelycontrol1gearandreversegear;block3andblock5,block2andblock4,block6andblock7,thatistosay,from1until6block,twoadjacentstallsareposedoftwoindependentforktorespectivelycontrol.Becauseofthisdesign,theshiftingprocesscanbefurthershortened:whentwoadjacentgeartogearswitch,ashiftforkandthecurrentgeargeardetachment,anothergearmeshinghasalreadystarted,andashiftforkactionandactivatestheelectronicclutchthree,becausetheactionisalmostsynchronously,sothatthewholetimeshorten.Lamborghiniisparedoriginallyclaimed,performanceisverygoodbeforethegenerationoftheE-gearsequentialgearbo*,shiftspeedupgrade40%,shiftspeedof50millisecondsisclosetoF1gearbo*level.GearshiftmechanismofISRisdrivenbytheelectrichydraulicpump,ama*imumof60barpressureensuresthenecessaryoperatingspeed,7hydraulicvalvecontrolsthegearshiftmechanismofaction,andtheelectricpumptoprovidepower,doubleplateclutchtoughalsodrivenbyhydraulicpressure,willberesponsibleforthetorqueofthe690Nmtransmittedtothefourwheels.Synchronizergearringismadefromcarbonfiber,notonlywearbutalsoreducetheoverallqualityofthegearbo*.Inthedesignprocess,thetransmissionisnotonlyfast,shiftqualityisequallyimportant,VOCISdesigncontrolprocedureisalsofullytakeintoaccountthedailydrivingfort.Thegearbo*canchoosethreekindsofworkmodes:Strada(Road)orfullautomaticmodecanprovidefortableforshiftoperationoriented;Sport(motion)modewillpostponeshiftingnodeandprovidesamorerapidgearswitch;Corsa(track)modelcanprovidethebesttrackshiftstrategy,themodelcanalsoprovidethestartingcontrol,alsoistheejectionstartfunction.1.2變速箱的換擋方式通常變速箱的分類為以下幾種：手動變速箱普通自動變速箱/普通自動變速箱帶手自一體CVT無級變速箱/CVT帶擋位的變速箱雙離合變速箱序列變速箱(1)手動變速箱手動變速器，也稱手動擋，英文全稱為manualtransmission，簡稱MT，即用手撥動變速桿才能改變變速器內的齒輪嚙合位置，改變傳動比，從而到達變速的目的。踩下離合時，方可撥得動變速桿。手動變速箱的工作原理手動變速箱是有不同齒比的齒輪組構成的，它工作的根本原理就是通過切換不同的齒輪組，來實現(xiàn)齒比的變換。作為分配動力的關鍵環(huán)節(jié)，變速箱必須有動力輸入軸和輸出軸這兩大件，再加上構成變速箱的齒輪，就是一個手動變速箱最根本的組件。動力輸入軸與離合器相連，從離合器傳遞來的動力直接通過輸入軸傳遞給齒輪組，齒輪組是由直徑不同的齒輪組成的，不同的齒輪比例所到達的動力傳輸效果是完全不同的，平常駕駛中的換擋也就是指換齒輪比。接下來，讓我們通過一個簡單的模型來給大家講講，手動變速箱換擋的原理。下列圖是一個簡易的3軸2檔變速箱的構造模型。輸入軸〔綠色〕也叫第一軸，通過離合器和發(fā)動機相連，軸和上面的齒輪是一個硬連接的部件。紅色齒輪軸叫做中間軸。輸入軸和中間軸的兩個齒輪是處于常嚙合狀態(tài)的，因此當輸入軸旋轉時就會帶動中間軸的旋轉。黃色則是輸出軸，它也叫第二軸直接和驅動軸相連〔只針對后輪驅動，前驅一般為兩軸〕，再通過差速器來驅動汽車。當車輪轉動時同樣會帶著花鍵軸一起轉動，此時，軸上的藍色齒輪可以在花鍵軸上發(fā)生相對自由轉動。因此，在發(fā)動機停頓，而車輪仍在轉動時，藍色齒輪和中間軸出在靜止狀態(tài)，而花鍵軸則隨車輪轉動。這個原理和自行車后軸的飛輪很相似。藍色齒輪和花鍵軸是由套筒來連接的，套筒隨著花鍵軸轉動，但同時也可以在花鍵軸上左右自由滑動來嚙合齒輪。說完這些，換擋的過程就很好理解了，當套筒和藍色齒輪相連時，發(fā)動機的動力就會通過中間軸傳遞到輸出軸上，在這同時，左邊的藍色齒輪也在自由旋轉，但由于沒有和套筒嚙合，所以它不對花鍵軸產(chǎn)生影響。而如果套筒在兩個藍色齒輪之間時，變速箱在空擋位置，此時兩個藍色齒輪都在花鍵軸上自由轉動，互不干預。一個傳統(tǒng)的5速手動變速箱換擋的原理也是一樣的，只是變速箱構造中增加了套筒和齒輪組的數(shù)目，使之擁有更多的擋位。而倒檔則是通過在中間軸〔紅色〕和輸出軸〔藍色〕之間增加一個齒輪來實現(xiàn)的。由于增加了一個嚙合齒輪，因此倒擋的齒輪始終會朝其他齒輪相反的方向轉動。這個齒輪由于只起到改變齒輪旋轉方向的作用，因此也稱為惰輪。5擋二軸變速器構造，輸入軸與主動齒輪整合為一體，簡化了構造也節(jié)省了空間除了上述的傳統(tǒng)三軸手動變速箱，目前轎車上廣泛使用的是二軸手動變速箱，它的構造和三軸變速箱根本類似，只是其輸入軸和中間軸整合為一根軸，因此具有構造簡單，尺寸小的優(yōu)勢，另外，它還有中間檔位傳動效率高，且噪音較小等特點，因此更適合一般的前置前驅家用車，是目前使用最廣的轎車變速器形式，它的缺點是不能設置直接擋，且一檔的傳動比不能設計的太高。而在后驅車上，使用較多的仍是傳統(tǒng)的三軸式變速箱。一般的手動變速箱，都是通過推桿連接或者是拉線來控制換擋的。推桿連接的換擋控制方式，更為直接但是傳遞的振動會很大；而拉線式的雖然沒有振動，但是擋位顯得不是很清晰，可謂是各有優(yōu)劣。除了這兩種純機械式的換擋控制，此外，還有使用電控裝置換擋的手動變速箱，它可以很好的結合推桿和拉線換擋之間的優(yōu)點。這種變速箱在換擋的時候，擋撥動變速桿到相應的擋位，在變速器里就會有電機驅動相應的撥叉控制套筒與齒輪咬合，因此不存在擋位不清晰的問題，而且換擋的行程也可以控制在很理想的范圍。則，一臺優(yōu)秀的手動變速箱需要具備哪些特點呢？首先變速箱必須要擁有良好的掛檔手感，每個擋位清晰，擁有合理的橫向和縱向行程，入擋的阻力小并帶有吸入感。除此之外更重要的是，各擋位之間的齒比排布必須合理。因為各個擋位間的傳動比分布，直接影響車輛行進中動力銜接的暢順性，通常要求低擋能有力加速，高擋能達致高速同時省油，且各擋間的距離要均勻，不然就會很容易造成換擋時竄車的情況。手動變速箱的優(yōu)缺點分析優(yōu)點顯而易見，它構造簡單，性能可靠，制造和維護本錢低廉，且傳動效率高〔理論上會更省油〕，另外，由于是純機械控制，換擋反響快，且可以更直接的表現(xiàn)駕駛者的意愿，因此也更富駕駛樂趣，這些都是手動變速箱的優(yōu)點。不過相比自動變速箱，它操作繁瑣，而且在擋位切換時頓挫明顯的劣勢也是無法彌補的。(2)自動變速箱自動變速箱簡稱AT，全稱AutoTransmission，它是由液力變扭器、行星齒輪和液壓操縱系統(tǒng)組成，通過液力傳遞和齒輪組合的方式來到達變速變矩。和手動擋相比，自動變速箱在構造和使用上有很大不同。手動擋主要通過調節(jié)不同齒輪組合來更換擋位，而自動變速箱是通過液力傳遞和齒輪組合的方式來到達變速的目的。其中液力變扭器是自動變速箱最具特點的部件，它由泵輪、渦輪和導輪等構件組成，泵輪和渦輪是一對工作組合，泵輪通過液體帶動渦輪旋轉，而泵輪和渦輪之間的導輪通過反作用力使泵輪和渦輪之間實現(xiàn)轉速差并實現(xiàn)變速變矩功能，對駕駛者來說，您只需要以不同力度踩住踏板，變速箱就可以自動進展擋位升降。由于液力變矩器自動變速變矩范圍不夠大，因此在渦輪后面再串聯(lián)幾排行星齒輪提高效率，液壓操縱系統(tǒng)會隨發(fā)動機工作變化自行操縱行星齒輪，從而實現(xiàn)自動變速變矩。為了滿足行駛過程中的多種需要(如泊車、倒車)等，自動變速箱還設有一些手動撥桿位置，像P擋(停泊)、R擋(后擋)、N擋(空擋)、D擋(前進)等。從性能上說自動變速箱的擋位越多，車在行駛過程中也就越平順，加速性也越好，而且更加省油。除了提供輕松愜意的駕駛感受，自動變速箱也有無法克制的缺陷。自動變速箱的動力響應不夠直接，這使它在"駕駛樂趣〞方面稍顯缺乏。此外，由于采用液力傳動，這使自動擋變速箱傳遞的動力有所損失。手自一體自動變速箱手自一體變速箱的出現(xiàn)其實就是為了提高自動變速箱的經(jīng)濟性和操控性而增加的設置，讓原來電腦自動決定的換擋時機重新回到駕駛員手中。同時，如果在城市內堵車情況下，還是可以隨時切換回自動擋。手自一體自動變速箱實際上還是自動變速箱的一種，最早出現(xiàn)在保時捷911上，手自一體變速箱通過電控系統(tǒng)模擬出手動變速箱的操作。它的出現(xiàn)，在操作上給予駕駛者更大的自由度，可以通過擋把上的加減擋或者方向盤上的換擋撥片來選擇自己認為適宜的擋位和換擋時機，從而大大提高了駕駛樂趣。(3)CTV無極變速箱CVT〔ContinuouslyVariableTransmission〕，直接翻譯就是連續(xù)可變傳動，也就是我們常說的無級變速箱，顧名思義就是沒有明確具體的檔位，操作上類似自動變速箱，但是速比的變化卻不同于自動變速箱的跳擋過程，而是連續(xù)的，因此動力傳輸持續(xù)而順暢。CVT傳動系統(tǒng)里，傳統(tǒng)的齒輪被一對滑輪和一只鋼制皮帶所取代，每個滑輪其實是由兩個椎形盤組成的V形構造，引擎軸連接小滑輪，透過鋼制皮帶帶動大滑輪。玄機就出在這特殊的滑輪上：CVT的傳動滑輪構造比擬奇怪，分成活動的左右兩半，可以相對接近或別離。錐型盤可在液壓的推力作用下收緊或張開，擠壓鋼片鏈條以此來調節(jié)V型槽的寬度。當錐型盤向內側移動收緊時，鋼片鏈條在錐盤的擠壓下向圓心以外的方向〔離心方向〕運動，相反會向圓心以內運動。這樣，鋼片鏈條帶動的圓盤直徑增大，傳動比也就發(fā)生了變化。CVT變速箱有哪些優(yōu)點？1、由于沒有了一般自動擋變速箱的傳動齒輪，也就沒有了自動擋變速箱的換擋過程，由此帶來的換檔頓挫感也隨之消失，因此CVT變速箱的動力輸出是