汽车专业英语(幻灯片)Chapter 5 Clutch(3.13.2).ppt

Review 1:Whats the main function of chassis?,Conveys the drive to the wheels,Absorbs the road shocks,Controls the direction of movement,Slows down the vehicle,Provides the support for automotive components,3.1 overview of power train,Review 2:List the main parts of chassis.,Power train,Running Gear,Steering System,Braking System,Power train,1Clutch 2Transmission 3UJ(Universal joints)4Drive shaft 5Final drive 6Differential 7Half-shaft,Running Gear,1Front axle 2Rear axle 3Suspension4Frame 5Wheel,Steering System,1Steering wheel 2Steering axle 3Steering gear/box4Steering knuckle 5track rod,brake pedal 2.master cylinder 3.metering valve 4.proportion valve 5.brake hose 6.disc brake 7.brake caliper 8.wheel cylinder 9.drum brake,Braking System,Review 3:List the types of chassis layout.,FF=Front Engine Front Drive,FR=Front Engine Rear Drive,RR=Rear Engine Rear Drive,MR=Middle Engine Rear Drive,n WD=All Wheel Drive,FF=Front Engine Front Drive,Advantages:1.Lower floor gives good cornering and low car gives small air resistance2.Short car3.Flat floor,no propeller shaft tunnel or gearbox protrusions4.Majority of weight at front gives good grip and good cornering,Disadvantages:1.Complicated structure and technology2.High cost3.Hard to service,Application:saloon car(Br.E.)=sedan(Am.E.),FR=Front Engine Rear Drive,Advantages:1.Fairly even load applied to each wheel 2.Main components easily removed 3.Simple type of universal joint is used,Disadvantages:1.Low efficiency 2.Big Weight 3.The height of floor is limited,Application:Most trucks,some saloon cars,some buses,RR=Rear Engine Rear Drive,Advantages:1 Large load on driving wheels gives good grip 2 Compact layout,short car,Disadvantages:1.Remote operating system is complicated located 2.Engine cannt prevent dust well 3.Hard to service,Application:Heavy and Middle passenger cars,MR=Middle Engine Rear Drive,Advantages:1.Concentrative weight 2.High efficiency 3.Good handling properties,Disadvantages:1.Engine needs special design 2.Hard to service 3.Complicated remote operating system,Application:Most sports cars,n WD=All Wheel Drive,Advantages:1.Fairly even load applied to each wheel 2.Each tire is evenly abraded 3.Best cross-country capability,Disadvantages:1.Complicated structure and high cost 2.Hard to service 3.Big weight and low efficiency,Application:Jeep and cross-country vehicles,Review 4:List the drive line of a FR Automobile.,Review 5:Whats the function of clutch?,3.2 clutch,It disengages the engine from the transmission to allow for gear changing.,It is a means for gradually engaging the engine to the driving wheels.,.dry friction clutch When a vehicle is to be moved from rest the clutch must engage a stationary transmission shaft with the engine;this must be rotating at a high speed to provide sufficient power or else the load will be too great and the engine will stall(come to rest).,当汽车原地起步时，离合器要将静止的变速器轴同发动机接合起来，此时发动机必须高速旋转以提供足够大的功率，否则载荷过大将引起发动机熄火。,To start the engine,the driver must depress the clutch pedal.This disengages the transmission from the engine.To move the car,the driver must reengage the transmission to the engine.However,the engagement of the parts must be gradual.An engine at idle develops little power.If the two parts were connected too quickly,the engine would stall.,为了起动发动机，驾驶员必须踩下离合器踏板，使变速器与发动机分离为了使汽车运行，驾驶员必须使发动机和变速器重新结合这些部件必须渐进的结合在一起发动机空转时产生的功率很小，如果两个部件很快的结合，发动机将熄火。,Coil Spring,Diaphragm Spring,Review 6:List the types of clutch spring.,Coil Spring Clutch,Diaphragm Spring Clutch,(Pressure plate),throwout bearing 分离轴承,Basic words,离合器从动盘,离合器盖,压盘,离合器分离叉,离合器分离轴承毂,Clutch housing,(US English)=Clutch plate,Review 7:List the main parts of a dry clutch?,Driving member,Driven member,Operating member,A driver depresses the clutch pedal to shift the gears inside the transmission.After the driver releases the clutch pedal,the clutch must act as solid coupling device.It must transmit all engine power to the transmission,without slipping.The dry clutch mechanism includes three basic parts:driving menmber,driven member and operating members.驾驶员踩下离合器踏板来换挡。当驾驶员释放离合器踏板后，离合器必须作为刚性连接装置，把发动机动力全部传给变速器而不能打滑。干摩擦离合器机构包括三个基本部件：主动部件，从动部件和操纵机构。,Driving member：,the driving member:The driving member consists of two parts:the flywheel and the pressure plate.The flywheel is bolted directly to the engine crankshaft and rotates when the crankshaft turns.The pressure plate is bolted to the flywheel.The result is that both flywheel and pressure plate rotate together.,主动部分由飞轮和压盘两部件组成。飞轮用螺栓直接连接到发动机曲轴上，随曲轴旋转而旋转。压盘与飞轮连接，这样飞轮和压盘一起旋转。,Driven member：,The driven member:The driven member,or clutch disc,is located between the flywheel and pressure plate.The disc has a splined hub that locks to the splined input shaft on the gearbox.Any rotation of the clutch disc turns the input shaft.Likewise,any motion of the input shaft moves the clutch disc.The splines allow the clutch disc to move forward and backward on the shaft as it engages and disengages.,从动部分（或从动盘）位于飞轮和压盘之间。从动盘上有花键毂，连接着变速器上带花键的输入轴。从动盘的旋转带动变速器输入轴随之转动。同样，输入轴运动也带动从动盘的运动当离合器结合或分离时，花键允许从动盘在输入轴上前后移动,The driven member:The inner part of the clutch disc,called the hub flange,has a number of small coil springs.These springs are called torsional springs.They let the middle part of the clutch disc turn slightly on the hub.Thus,the springs absorb the torsional vibrations of the crankshaft.When the springs have compressed completely,the clutch moves back until the springs relax.In other words,the clutch absorbs these engine vibrations,preventing the vibrations from going through the drive train.,当从动盘的内侧（毂缘）有一些叫作扭转弹簧的小螺旋弹簧，这些弹簧使得从动盘中部相对从动盘毂能有轻微转动，从而吸收曲轴的扭转振动。压紧弹簧完全压缩时，离合器向后移动直到弹簧开始伸张为止。也就是说，离合器吸收发动机的振动，防止振动传递给传动系。,Clutch Disc with torsional spring,Not Working,Working,operating members:These are the parts that release pressure from the clutch disc.The operating members consist of the clutch pedal,clutch return spring,clutch linkage,clutch fork,and throwout bearing.The clutch linkage includes the clutch pedal and a mechanical or hydraulic system to move the other operating members.,操纵机构释放离合器盘的压力。操纵机构由离合器踏板、回位弹簧、离合器杆系、分离叉和分离轴承等组成。离合器杆系包括离合器踏板以及用来操纵其它部件的机械式或液压式操纵系统。,Mechanical Clutch Operating System,Hydraulic Clutch Operating System,踏 板pedal,储 液 室reservoir,主 缸,工 作 缸Slavecylinder,分离轴承Throwout bearing,分离杠杆Release levers,分离叉release fork,推 杆Push rod,推 杆,operating members:When the clutch pedal is depressed,the clutch linkage operates the clutch fork.The clutch fork,or release fork,moves the throwout bearing against the pressure plate release levers.These levers then compress springs that normally hold the clutch disc tightly against the flywheel.,踩下离合器踏板，离合器杆系操纵分离叉。分离叉带动分离轴承压向压盘上的分离杠杆，分离杠杆压缩压紧弹簧。通常情况下，压紧弹簧使从动盘和飞轮紧密接合。,operating members:When the clutch pedal is released,the pressure plate forces the clutch disc against the flywheel.The clutch return spring helps raise the pedal.,释放离合器踏板，压盘使从动盘同飞轮接合，回位弹簧使离合器踏板抬起。,Drive line,friction face-,clutch disc-,trosional vibration balancer-,splined hub(clutch disc)-,input shaft of transmission,Flywheel-,Pushing centre of diaphragm inwards causes outer edge to move away from flywheel.,Diaphragm spring pushes pressure plate against driven plate.,Release bearing held clear of diaphragm spring.,The hydrodynamic coupling:Most automatic transmissions use a hydrodynamic coupling to join the engine crankshaft to the transmission input shaft.Hydrodynamic couplings and hydrodynamic torque converters transfer the torque through fluid-flow forces.They provide advantages when driving away thanks to infinitely variable conversion of speed and torque,with the maximum torque being available at the drive-away point(engine turning,vehicle stationary).,大多数的自动变速器使用液力偶合器来连接发动机曲轴和变速器的输入轴液力偶合器和液力变矩器通过液流力传递扭矩它的优点是起步时提供连续变化的速度和扭矩，在起步时(发动机运行，车辆静止)得到最大扭矩,The hydrodynamic converter:,1)the pump,which is connected to the engine,acts like a centrifugal pump to produce the flow energy of a fluid;,2)the turbine,which is connected to the transmission input,converts the flow energy back into mechanical energy;,3)the reactor，between turbine and pump diverts the flow of the fluid.,