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Transmissin (mecanis) ransmssin or gearox prides speed nd toqu conversions fo a oaigpor soce to aothe device using ga ratisn BritishEnglishthe tem tanissi reer ote he drive trai， icuding gearbx, luch， popshat(r rea-heelrive),ifretil and final dive shafts. Temst cmon use is n mor vels,wee hernsmissin dapts thoutput o te intnalcombustio engie t the rie hel. Suegin eedtoprae at a ratvey highroationalseed, whh is iaproprite for strting, stoppng, andslower rvel. T transmion redues he igher engn sped to theslowheel peed, incresing toqu n theproces. Trnisina alsoused o pel icycles,fixed ains,nd anwher lse rotaiona eed and oquneed o be adape.Ofen, sssion wil hve multple garraios (or simply gar), wit te ability swih between them s ed varie. Ti switching y boe manually （y thepeato)， or utoacaly. Diretonal（forard ad revere) cntay ls be poied Singe-raio transmisson loexit, wich smy chage the speed adtrqu (noeimsdiectio) of otor uI motor vle applcatios， the tnmissiowillerl e nnected to heraksa fte engine. The oupu fhe rasmsionis ranited vi diveshftto e rmrediffrentias, whichin tur drivtheels. Whie a diffentil y also pvide gear rectin, t primary purpse ist ne the decion of roati.Coventioa ge/e tanmissins areno the only mechaism fr seed/orqudaptation.lternativemchanisms ince trqe cnverters and owe tansformaton (eg.， dieselelectritransmissio， hyraulic drve tem, e.) Hybid oniuransalso eist.xpatonEay rnsmision icudeh rightangle drives andoer ern in widmill, orseped devi,a sta nin, i sport of pm,milln, an hoisting.Most moder goes areuse to ncree orqu hil educng e sed of a pr verututshaf (e.g. a otor crankshaft） hs mnstha the outpthat a earbox wl otate a slowr t than he inpt hft, and th redcion in speed illrodue amechanicl advatage, using an ireas i oru. A gearoxcan e setup todotheoppoite an proiean ineas inshaftsped with a euction oftorqe Soe of te smplest gearboxes merelchage he phyical directin in wich poer i transte.Many typicl atoieransmissios include theltyoelect one o seerldifeent gear rato. In thscase, most he gearrtio (ftnsim caledgs)ae ued t lodowte outpu speed o the engn ad inreseore. Howver,e highest ear ma bovrdrive typesthat inceas theoute.UssGearboxes hav foud u n a idevaet ofdffentftn sationaypplicatis， such as wind tubine.rnsissineso ue i arculual, industria，onstutio, mnin and autooti qet. n addtion rdiarytramissoneqipped with gears, such equipent maks xtensive se o th ydrosticrive and elctcl adjusale-sped drves.Smlhe simplest transmissions， oten called gearboxesto reflect theirsimliciy （altog comlex systes ae als called gearboxe int vernular),rovide gear ecto (r, more rary, nincreas n se), ometmes onjunctionwi a ih-ale change n iretioo theshaft (tpicly n eicopters,se pice）. Tee are often ed o PTO-powredagiculturleuipme， since te xialTOhaftis at oddswith th uualeed for the divn sat， whichs ethr vrtical (s with otary mowers), or riontallyeendingfromne sief the impement to anotr (s wihmanur srad，flai mwer， and forag aon） More comxquipment, such s silag chppr andsnwbowers, e drivs wi outputs imorehanone rectonhegarbox i awnd ubincnvet the slow, high-torque roinof theturin ino uch fastrtation fh lectrical genro. Thesea uclrgrand r omplcad thathePTO geaboe in aruipment. Thy wegseeral tonsad typiclycntan three sts t achev n overl gear ratio ro 40：1t oer 100:1, depedig n te size o he turbine（or aerodynamic andstructuralreasons, larger trines hae to rn mre slowly，ut the gror all have o roteat imilr sped o seral tousnd pm.) Thest stage of tgearosuualnetary gear, for compatnes， and t stribute the eomus tqu o he turbine overmore eth o thelow-speed ha.Dabilit of these geboeabeen a serusproblm for a long e.Regdles ofwere are ed, hese impl ransmissons al share a mpornt eature: the geartionnbe cangdurin use It sxedt t i tetansmiin is contucte.Fr transmissiontps tat vrcome this ssue, ee ontnuousl Variale Transmission， also know VT.Mlti-rtosystmany applictns require te alablit of mltileear ratis. fn, ts iso eee stating an stopping ofaehanical system, though aother imortat nd s at of aiainnggo f eficie.Autootve bscshe ee fora tramission nautoobie iacneence oft cheristics ofthe nternal cmbsion enine nines tpcally perate ovr rangeof 60 to about 7000 eolution pr mute（though ti ars， and is typicall lessfor dieel engin)，whie thecarswhee roae bwee rpm and rond1800 rpm.Futhrore,theinprvides is igest torque oupus apprxmatey i th iddlofits range,wie ftn thegreat torqe is reqired he the vehcle is movg froest o aveling slowly. hefor， a steattrasforms the ennes oput so hat it canspplyhig toqe at lo peds， ut aso operate t highy seedswi heotor stilleratnithin its imts, s required. Transmission perfomhis trnsfmato.Mantrasmsions and gears sed inautomotie andrck pplcation are cnained i a cast irn cae, thugh moe fretlyamium is sed r lower g escilyincrs.There suallthre shafts： a mashf, uteshaft, andan ler hft.The mainshftextends outide te caeinbth directions: the inut shat ordte enge, and the outpu haftowards th rer ale (on rer whel driv ars-frot whel is genraly hvete engn ad tnsmissiounted trnserse, t diffeental beig pat of the transmission asseml.) The sht iuspended b te main bearing,ad s split toards the iu en.At theoi thsplit,a piltberng hods he saftstogther.Th gears and cluthes ide on the mishat, h grs beigfree o turn relative tohe mainshf ecept whenngagd by th luhes.Tpesofuomoble tasisions iclude aual, auomatc or semtmtitransision.analain atl:ManltransissionMnual tnmisson me in t asic type：asimpleut ruggedslidng-mesh r nsyncronized / on-nhronous sye， wre stagt-cut su gear setsae spinnn feely, adust syncroized b thepertormching engine rev o rod sd，tovi noiyan daagin ear cash, an the o cmmo cnstant-mesearxes wh can includ nn-ynchronised, or synronized / schomeh yms, whe dagn ct helical (ansomeies doue-hlical)gr ts ae consatly mshe togeter,ad a og cutch is usd for hngggeas. n synchomeshboxs， frtn cones orscho-rin a sed in additino the dg cluch.T forertpe is cmmonl foundinany form of racncars， older heavyduty trucks, adsome agricltural quimen.Mua ransmiion are the ost mmon tye outsde t Aeica and Austal. hyarechaper， lghter, usually gve beterperfomance,an fuel effiiency (ahough thelt shstitedautomatc rnsmisos ay yieldeults igty bet hanthnsyeled b manua trnsssons). t is cutma forndrvrs o learn, n be teted,on ar th manual gerhange. InMalysi,Denar nd Poand llcas sed fortestin(anbecse of hat， italyll those sd frinsructonaswell) ave anu ransmission In Japan, th hiipines,Grany， Italy， Ire， e ethrands, Begium,Ne Zeand, Austria,Buaria, the UK， read， Swede, Etonia, Franc， Sain, Swizrlad, the Austlianstes Victoria and uad, inland andLithuania，att pas using anautmati ca does notenttle t driverouse a mal r on te publiroa； a tes wih amanac srequireaual tamns ar much more comon thanautoatic transmission inA， frica， SouthAmrica and uoe.Mot manal rsmission icudbothschronzd nd nyconizegeaing，c as aevers gearan alow-spee ganny ge, oto which can ony behift int w toped hfng rm gann gear t a lo ynchrizedgear is genrally available while i in，whie shifting ot of reerseo an other ge typcl rquires theehit e toppe.NoyncronousMain atile:Non-syncronou trasmissionsThere are commercil appltions engined with designstakin nt acount that te gear hiting wile ne by nerience oprtorTey are a mnuatrnsmisin, bu are kown a nonsyncnized trnisio. endent on coutry of opeaton, many lal,egional, andntional laws governheoperation fes tpeof ehicls (eomercia Drverscnse）. hlass a inlude comrial,military,giultual， or enineerigvehicle Som f tesmay coitions of yps o mliurpose funcios. n amle oulbe a PTO， orpowr-takeof gr. The n-synconu ranmisson type eqiresnundersandi o gear range, orqu,enginpowe, and multi-fuctiona cluch nd shifter untns.lsoseeDoble-cltchng, nd Clutc-brake sections fhe main artile at osyncronu ranissiosAuomatcin atcl： Automtic trnssionEpicclic gern oplanta garig a use in a utmatic ranmisionMotmdn NtAeicn an Astalian an many larger，ig specfiation Eroen nd Japeecars have a automaic trnsmison hatwllelct a apprpriat gr atio wito ayoperato iterventi. They priarly us dralcs oselc gear, depednon rsseexere y fluid wthin th transission assembly Rather thusing utch to engage h trnsmssion, fluid flheel, rtoqu onverter is laced inbetwenthe enine transmission. I ispossile f he rivr tocotrol the nmbero gears ins or select revrse, tough precise ctrol o which ear i n uemay ormay notbe pssibAtomatictransmisions ae easy to us.wever, nthe past， automtic ransmisis of this pe have hada umber of prblms;tey were complx ad expensive,seties h rliabili rblems(hic sometms csed more xpnses n reir), hav otnbeenlessfu-eficientha thi ancntrparts （duto slpgeinthtorque convtr), an hr shifte a slowr tan manualking temuncmpeitive or acing Wih the advament of modenauom transmsins thshas chaned.Attps to improvethe fuel effcincof automattrnsssionsinclude thesof orqnvertes wichlok u beyond acerain pee,or in te hr earrtio, elinating oer loss, and vrrive ars hc auoaically actuat bove certin speds；n lderanmissiosth technoogies old ometimesbecome inue, en codiionsar ch tht hey repetedly cut in and ut as seed ad sch lo fats as gde or ndvar sighly.Curen computezed trnisions sevry cmpex rograming to boh maximizfel ffcieny ad limnaean inusienss.Fo ertan pplcations,te slippag inhern in autmatc tansmisions cabe advantageous; for instance, in dg rang, heautoatc transmsion allows th car o eoped withthe engie ata high rpm(th sa eed)o alow for a euick launch when the brakes re relesd; in fac, a ommon modifiaion i toinra the stlspeedofthetransmissi Tiss even more advnta fturbochargdegnes, whreth urbochargeneeds t bkep spiin t high pm by a large low of exhust inor to kep he oostprsu u n liminat th tubo lagtt occurs whenhe enine is idlin and the trtl sudelyopeeSmiautomticMan are:Semitmtic trnsisionTe tio o ouer conrol alo aledfor a s of cos-bred tanmission ee th cr handles maniulatiof he clutch utomatically,but the divercn sill seec the gear mnully feired.Thi is soetiescale a cutchless nu, orautomatd manual tansmision.Man o tese transmisin alw th river ogve full controlo te outer They regeneralydeigne sin aual ransmsontena， ad when sedi pasener crs, aveynchoehoperte heiclnstat sh gea sts.Secfic pe of thi transison ncludes: asytroni, ad Gearrnic.A dual-lutrnsmisio uses wo set of intenals whih re alernteyused,ec w its wncluth, sothat onl te cluches re sed during h acta eachge.Speii type f this trassioincludes: Direct-Sftaro.here realsosequetial trasisios wih e the roatin of adr t sitcger.Bicycle earngMin rtcles: yce gearing, Derilr gears，a Hub gearBicycs sually hea system for slting diffrent ge rtios. here r two mainypes: derailler gea an b geas.The ailler tye ithe mot cmmon,d h most visible， uing sproket ears.cally ere arsvea gears avalable on he reasproketasseml, athed o terea wheel. A fw moe sprocksare usuaydded to the fron assembly ell. Multiplyg the numb ofsprocket easinfro by te ubertothe reargies te nuberof gar ratios, oten alledspeeds.ub gears se epicyclc garing nd arenclo withn e al of the rear wheel.Beause of the smll spe, theytypically ofe wer diffrentspds,lthh aleat one ha eachd 14 gear ratios n FalbookTehnoogiemanactus traissn w tecical nfinite ratios. auses o failre o bcyleing iclu: or teeh, damage caused by a fult ch, damag du to thrml expanion, rokenteethue to excssivepdali foc,interfence by forignbjcts, and ls ubicaion due o neligence.Uncomon tysDua clutc rnsmissionMaiarticle: Du cluh transmissionThis arragementi lsosometies knon as a diet shit gearbox o powershift erbo. Itseks to cmbine the advantage ofa conventiona manal sitth the qualies of a mdrn automat ranmissi by pridng different clutce odd an v sped slcoears. hen chaging ar, theegne tque istransfrrd fro oneear tth ohcntnosly， so priding gntle, sot gar changs wiouteter li power o jkin he ehic.Gea seletomy be anual, atoti (depeng nthrotlspeesenos), o a sorts verion cbining both ptions.Cotnuouly variableMn arile: Contiouly vriab transshe Cninuousy Variabe rasmissin （VT)is a transissionn which heato he aionalpeeds of to shats, steipu hafand output shaf of a vehicl o therahine， an be vaied oiuusy withn a gven range, riing annfinite numbe ofposible ratis.Te contiusl vriale trnmission() oud otbeconfusedwithtenfnitly Varabe Transmion （IV)（See below).Th the ehnical tramisions desribd above alowfew differn gerraios to belec,but tis tp of rnsiionsnially ha an infinite ubr of raios avaiale withn a finite re continuouly ariabl rnmisionallows terlionship beteen the speedof the engin ad the speed of t heels tobeseete withn acons range. Thi canpride eenbetr fuel enoy ifthe engine isconstatyunnin a a single sped.he transmisson i they capl f a bettr user experince， wiout the rie and fall in sped oan engie, and thejer fet he ply chaning gers.Innity variableheIV is a secfi tpe f CT hat has an infinite range finpu/outpt iosi dditio toitsinfini nber ossible ratios；ths ualifcaion fo teVT imlie that its range of rati includes a zer outut/inut to that cn be contiuul aproace frm a defied igher ati.A zeootput imliesa infinteinut, hh cn be cntisy apprchd frm agivn fnite inpt vle withaI Noe: remmber ht socalleow gears area referce o lo ratsof utpt/put, whch hav ighinutupu ratos thatare ta t he extree ith IT, rulting in a ural，or non-drivigowgeaiit.ost( nt ll) IVTsrsltrom te combinaion of aVT with aneiclc gerste （which al kon sanetary gear system) that failitats te subtractin o nespee fomanter spee it thset o iput d plnaygear rotationshs sutrction only neds t rsut n acontinuus rage of vue tha incues a zero otput； themaximum outpt/put rio can e rbtrarly chosfominite rtcal possibilities thrgh sltio ofextraneousiut orutpu gear, plley r prockt sizes witout affetin the zrutput o h coninu o he whoe system. mpranly， the IT s disiguishedas be infniteinits aio o hih gear to lw ger ithn its rae; hgh ga is infinitetie hir tan lw gear.he VT ialas engd, een dring ts zeroutut adjstmeTe tem infnitely riable ransision does not iml eers direction，dsengagnt, autotc operato， or ny oherqulityecp ratio seectabiliy within a cotinous ang of iput/outut ratios rm adefnemiimmto n undefd, infinite maxium. Tisman onnuus nge froa defieutuinpt to ero ott/nutratio.ElecticvriableThe Elctric ariabe ransmsio (EVT) s a tansmssion that achiee CTaction ndin adioncn ue serte powrnputs to produce oneouput. An T usual is eecte ndsign withn epiylc ifferenal earsstm(whichis alsokown asa laetary geasystem). Te eicycli diferentl garinperfom a powersplt tion, dirc conntig aprt ofh mechanical oe drlythroh the tnsinand splingof aprton foubsquetconverion elctial por via a motr/geeratr. ene, thETis clled a PweSplit Tranissn (ST） by someTh irty connecd poronof t ower trelghrough the VT is referd ost echicalph. Te ainigper travesdwnth EVTs lectrcl pth. That poer ae ecombinedat the ouput of the trasmiio or sted for later,orepprtuneuvia a ecnd motor/geato (an enry storae dvi) concted toth triion outuhe pair of motorgeatorsformsa Eleci ransmission inits own rght， bu talow cpacity, than th EVT i is cnaned ithi. Generally the ctrc ransmisson cpty withn th EVT is aquate toa alf of the cacit o the V. Good reaos to us
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