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How ClutchesWorkIf youdrive amanual transmissioncar,you maybe surprisedto findout thatit hasmore thanoneclutch.And itturns outthat folkswith automatictransmission carshave clutches,too.In fact,there areclutches inmany thingsyou probablysee oruse everyday:Many cordlessdrills have aclutch,chain sawshave acentrifugal clutch and evensome yo-yos havea clutch.入CInicp Ill|ge CgUeLD!gLgll|o\cgL2poM!u cln!cp Iocg!!ou.eee llloLedn!cp!ll|ge2In this article,youll learnwhy you need a clutch,how the clutch in your carworks andfind outsomeinteresting,and perhapssurprising,places whereclutches canbe found.Clutches areusefulin devicesthat havetwo rotatingshafts.In thesedevices,one of the shaftsis typicallydriven byamotor orpulley,and theother shaftdrives anotherdevice.In a drill,for instance,one shaftis drivenbya motorand theother drivesadrillchuck.The clutchconnects thetwo shaftsso that they caneitherbe lockedtogether andspin atthe samespeed,or bedecoupled andspin at differentspeeds.In a car,youneeda clutchbecause the engine spinsall thetime,but thecars wheelsdo not慢,使发In orderfor acar tostop withoutkilling the engine,the wheelsneed tobe disconnected动机迅速升温,以适当的操作温度许多汽车有限滑差或者粘性联轴器,两者都使用离合器,以提高牵引力当您的汽车变成一个车轮转动速度超过了其它车轮时,这使汽车难以对付在防滑差速器以及离合器的匡助下,当一个车轮转动速度超过了其它车轮,这样会使离合器缓慢下来,并符合其它三个车轮的转速车下有水坑的水或者浮动的冰块也可以让车轮空转您可以了解更多关于差速粘性联轴器在如何工作天然气动力链锯离心式离合器,从而使链反转可以住手旋转,而您不需要关掉引擎这些工作自动离合器通过利用离心力输入连接到发动机曲轴输出可以驱动链条,皮带或者骨干由于轮调,每分钟增加,逼迫滚珠移出,并迫使离合器进行离心离合器也往往发现于割草机,卡丁车,轻便摩托车和小型摩托车甚至一些缆车离心离合器from the engine somehow.The clutch allows us to smoothlyengage aspinning engine to anon-spinning transmissionby controllingthe slippagebetween them.To understandhow aclutch works,it helpsto knowa littlebit aboutfriction,which is a measureofhow hardit isto slideone objectover another.Friction iscaused bythe peaks and valleysthat arepartof everysurface--even verysmooth surfacesstill havemicroscopic peaksand valleys.Thelarger thesepeaksandvalleys are,the harderit isto slidethe object.You canlearn moreaboutfriction in How BrakesWork.aA clutch works becauseof friction between aclutch plateand flywheel.Well lookat howtheseparts worktogether in the nextsection.Fly Wheels,Clutch Platesand FrictionIna cars clutch,a flywheelconnects to the engine,and aclutch plateconnects to thetransmission.You cansee whatthis lookslike in the figurebelow.When yourfoot isoff the pedal,the springspush the pressure plateagainst the clutch disc,whichin turnpresses against the flywheel.This locksthe engineto thetransmission input shaft,causingthem tospin atthe samespeed.©2000Hg SiurrPressureplateThe amountofferee the clutch canhold dependson the frictionbetweenthe clutch plateand the flywheel andhow muchforce the spring putson thepressure plate.The frictionforce inthe clutchworksjust likethe blocksdescribed in the frictionsection ofHow BrakesWork,exceptthat thespring presseson the clutchplateinstead ofweight pressingthe blockinto theground.When the clutch pedalis pressed,a cableor hydraulicpiston pusheson therelease fork,which pressesthe throw-out bearingagainst themiddle ofthe diaphragm spring.As themiddleof thediaphragmspringis pushedin,a seriesof pinsnear theoutside ofthespringcauses thespringto pullthepressure plate awayfrom the clutch discsee below.This releasesthe clutchfromthe spinningengine.Common ProblemsFromthe1950stothe1970s,you couldcount ongetting between50,000and70,000milesfrom yourcarsclutch.Clutches cannow lastfor morethan80,000miles if you usethem gentlyandmaintain themwell.If notcared for,clutches canstart tobreak downat35,000miles.Trucksthat areconsistently overloadedor thatfrequently towheavy loadscan alsohave problemswithrelatively newclutches.Photo courtesyCarolina MustangTheclutch onlywears whilethe clutch disc and theflywheelare spinningatdifferentspeeds.When theyare lockedtogether,thefrictionmaterial isheld tightlyagainst theflywheel,and theyspin insync.Its onlywhen the clutchdiscis slippingagainsttheflywheel thatwearingoccurs.So,ifyouare thetype ofdriver whoslips the clutchalot,youll wearout your clutchalotfaster.Sometimes theproblem isnot withslipping,but withsticking.If yourclutch wontreleaseproperly,it willcontinue toturn theinputshaft.This cancause grinding,or completelypreventyour carfrom goinginto gear.Some commonreasons aclutch maystick are:Broken orstretchedclutch cable-The cableneeds theright amountof tensionto pushand pulleffectively.Leaky ordefective slaveand/or masterclutch cylinders-Leaks keepthe cylindersfrombuilding thenecessary amountof pressure.Air inthe hydraulicline-Air affectsthe hydraulicsby takingup spacethe fluidneeds tobuildpressure.Misadjusted linkage-When yourfoot hitsthepedal,the linkagetransmits thewrong amountofferee.Mismatched clutchcomponents-Not allaftermarket partswork withyourclutch.depress fully.If youhave topress hardon thepedal,there maybe somethingwrong.Stickingor bindinginthepedal linkage,cable,cross shaft,or pivotball arecommon causes.Sometimesa blockageor wornseals inthe hydraulicsystem canalso causea hardclutch.Another problemassociatedwith clutchesisaworn throw-out bearing,sometimes calledaclutchrelease bearing.This bearingapplies forcetothefingers ofthe spinningpressureplateto releasetheclutch.Ifyou heara rumblingsound whentheclutchengages,you mighthaveaproblem withthethrow-out Typesof ClutchesThereare manyother typesof clutches in yourcar andinyourgarage.An automatictransmission containsseveral clutches.These clutchesengage anddisengagevarious setsof planetarygears.Each clutchis putinto motionusing pressurizedhydraulicfluid.When thepressure drops,springs causetheclutch to release.Evenly spacedridges,called splines,line theinside andoutside oftheclutchto lockinto thegears andthe clutchhousing.You canread moreabout theseclutchesinHow AutomaticTransmissions Work.An air conditioning,compressor inacarhas anelectromagnetic clutch.This allowsthecompressor toshut offeven whiletheengineis running.When currentflows througha magnetic;coil intheclutch,theclutchengages.As soonas thecurrent stopssuch aswhen youturn offyourairconditioning,theclutchdisengages.Most carsthat havean engine-driven coolingfan havea thermostaticallycontrolled viscousclutch--the temperatureofthefluid actuallydrives theclutch.This clutchis positionedatthehubof thefan,intheairflow comingthrough theradiator.This typeof clutchisalot likethe viscouscouplingsometimes foundin all-wheel drivecars.The fluidintheclutch getsthicker asit heatsup,causing thefan tospin fasterto catchup withtheenginerotation.When thecar iscold,the fluidintheclutchremains coldandthefan spinsslowly,allowing theenginetoquickly warmup toitsproper operatingtemperature.Many carshave limitedslip differentialsor viscous couplings,both ofwhich useclutches tohelpincrease traction.When yourcar turns,one wheelspins fasterthan theother,which makesthecar hardto handle.The slipdifferential makesup forthat withthe helpof itsclutch.When onewheelspins fasterthan theothers,theclutchengages toslow itdown andmatch theother three.Driving overpuddles ofwater orpatches ofice canalso spinyour wheels.You canlearn moreaboutdifferentials andviscouscouplingsinHowDifferentials Work.Gas-powered chainsaws andweed eatershave centrifugal clutches,so thatthe chainsorstrings canstop spinningwithout youhaving toturn offtheengine.These clutchesworkautomatically throughthe useof centrifugalforce.The inputis connectedtotheengine crankshaft.The outputcan drivea chain,belt orshaft Asthe rotationsper minuteincrease,lighted armsswingout andforce theclutchtoengage.Centrifugal clutchesare alsooften foundin lawnmowers,go-karts,mopeds andmini-bikes.Even someyo-yos aremanufactured withcentrifugalclutches.Gutches arevaluable andnecessary toa numberof applications.For moreinformation onclutchesand relatedtopics,check outthe linkson thefollowing page.离合器工作原理如果您驾驶手动变速箱的汽车,您可能会惊讶地发现,它有一个以上的离合器事实证明,与自动变速器汽车离合器相比,有许多种类离合器在你可能看到或者每天使用许多无绳演习有离合器,链锯有离心离合器,甚至一些部件也有一个离合器Diagram ofcar showingclutch location.See moreclutch images.在本文中,您会了解为什么你需要一个离合器,在您的汽车离合器工程和一些有趣的发现,也许不足为奇离合器是实用的设备,有两个旋转轴在这些设备中,其中一个轴通常是驱动马达或者滑轮,其他轴驱动其他设备例如,一轴驱动机电和其他驱动钻夹头离合器连接从动盘和压盘,以便它们可以被贴在一起,旋转同样的速度,或者脱钩,并以不同的速度旋转在汽车中,您需要一个离合器,因为发动机的转速所有的时间中,但并非所有的时间都传递动力为了让汽车住手传递动力不造成发动机过载,车轮需要断开辟动机传递动力离合器使我们能够顺利地进行旋转发动机的非线性传递,通过控制离合器压盘与磨擦片之间的滑动了解离合器的特点,它有助于了解一点磨擦片,这是衡量离合器的标准磨擦所造成的传力高峰和低谷的每一部份,每一个平面甚至是非常平滑的表面仍然有弱小的高峰和低谷这些较大的高峰和低谷,就是磨擦片研究的对象您可以了解更多关于离合器如何磨擦工作离合器的工作,产生于磨擦离合器压盘和飞轮我们将探讨如何共同工作,这些零件将在下面介绍飞轮,离合器片和磨擦在汽车的离合器,一个飞轮连接到发动机,离合器踏板连接传输当你的脚离开踏板,弹簧推动压力板对离合器盘,而这反过来压力又回位这种转速控制包括发动机,变速器输入轴,使他们自旋同样的速度©2000Hg Siurr压盘离合器传递的动力取决于磨擦离合器盘和飞轮,有多少转矩通过飞轮压盘传递给膜片弹簧磨擦离合器作用就像描述的磨擦制动器的工作一样,但弹簧压力离合器压盘不是像制动器那样依靠抱紧制动盘当离合器踏板被踏下时,机械或者液压活塞推动拨叉,这些压力通过分离轴承对中间的膜片弹簧起作用把膜片弹簧是推离了压盘的附近达到让离合器分离的效果请注意弹簧离合器从动盘这些弹簧有助于缓解传输的过大动力冲击离合器盘毂这种设计通常非常有效,但它确实有一些缺点让我们分别看看离合器问题和其他用途的离合器在以下的内容中讲解0208HowSiufTMiX从动盘常见问题从世纪年代到世纪年代,你可以指望得到万至七万里程汽车的离合器离合器现在可以超过去年八点零零零万英里如果您使用它们轻轻地和维持好如果不是照应,离合器就可以开始打破在英里卡车一贯超载或者时常拖重物,也可以有问题相对较新的离合器最常见的问题是,离合器磨擦材料的磨损磨擦材料在离合器盘非常相似的磨擦材料的垫片的盘式制动器的鼓式制动器过了一段时间,它磨穿了当大部份或者全部的磨擦材料已经一去磨损了了,离合器效率将开始下滑,并最终将不会传送任何转矩从发动机到车轮离合器只能传送离合器盘和飞轮的旋转速度不同当他们被锁在一起,磨擦材料是紧密举行接合与飞轮,他们自旋同步惟独当离合器盘下滑对飞轮的穿着发生因此,如果您是一个司机,踩离合器的次数多,您的离合器磨损快得多有时,问题不在于传递的磨擦力下滑,但问题是如果您的离合器装配不正确,它将继续联入输入轴这可能会导致磨,或者彻底防止您的车进入齿轮一些常见的原因可能导致离合器出问题损坏或者拉伸离合器拉线拉线需要适量的张紧力液压泵有缺陷或者主离合器液压瓶泄漏保持液压瓶必须建立必要的压力空气中的气压线空气影响液压,空气流体需要建立适当压力不匹配的离合器组件并非所有的售后配件与您的离合器能匹配“硬”离合器也是一种常见的问题所有离合器需要一些相应的转矩范围如果您必须紧逼踏板上,可能会有一些错误的坚持或者有约束力的踏板联系,电缆,交叉轴或者旋转球的常见原因有时阻塞或者磨损在液压系统也可能导致硬离合器另一个问题与离合器是一个破旧投掷出轴承,有时称为离合器释放轴承以手指旋转压力板松开离合器如果你听到隆隆声时,离合器继续接合,您可能有一个问题,间隙没有调整好离合器诊断试验如果您发现您的离合器已经失效,这是一个在家的诊断测试,任何人都可以执行启动你的车,设置停车歇息,并把汽车停在原位让您的汽车空转,听取了咆哮的噪音的前提下,如果你听到离合器有这种声音,这是最有可能传输装置有问题如果您没有听到噪音,请继续执行步骤让汽车仍处于原地,开始推动离合器和聆听噪音如果你能听到一些唧唧噪音,这是最有可能的离合器分离轴承的故障如果您没有听到噪音,请继续执行步骤用尽全力推动离合器如果你听到尖叫声的噪音,可能故障出自轴承或者套管如果你听不到任何噪音在这四个步骤,那末你的问题可能不是出自离合器如果你能听到的噪音,并在住手时消失时,离合器可能的一个问题是离合器的控制机构出了问题在以下的内容中,我们会研究一些不同类型的离合器以及他们如何使用各类离合器还有许多其他类型的离合器在并不在您的知识库自动变速器包含几个离合器这些离合器接触和脱离接触的各种成套行星齿轮每一个离合器付诸实施使用加液压油当压力下降,弹簧导致离合器分离间隔均匀的离合器锁环,称为样条线的内部和外部的离合器锁定齿轮和离合器你可以看到更多关于这些离合器在自动变速器如何工作空调压缩机的汽车有一个电磁离合器这使得压缩机即使在引擎关闭也能正常运行当电流流经磁场线圈的离合器,如当您关闭您的空调,离合器分离大多数汽车的发动机驱动的冷却风扇的温控粘性离合器温度流体实际驱动离合器这离合器是处于枢纽的地位,气流通过散热器这种类型的离合器是一种很像粘性联轴器,在全轮驱动汽车时常浮现液体离合器较多,因为它热量大,导致风扇旋转的速度要快赶上发动机旋转当汽车是冷车时,流体在离合器仍然寒冷,风扇转速。