车辆工程机动车离合器的外文文献翻译

CLUTCHThe engine produces the power to drive the vehicle. The drive line or drive train transfers the power of the engine to the wheels. The drive train consists of the parts from the back of the flywh eel to the wheels. These parts include the clutch, th e transmission, the drive shaft, and the final drive assembly (Figure 8-1).The clutch which includes the flywheel, clutch disc, pressure plate, springs, pressure plate cover and the linkage necessary to operate the clutch is a rotating mechanism between t he engine and the transmission (Figure 8-2). It operates through friction which comes from contact between the parts. That is the reason why the clutch is called a friction mechanism. After engagement, the clutch must continue to transmit all the engine torque to the transmission depending on the friction without slippage. The clutch is also used to disengage the engine from the drive train whenever the gears in the transmission are being shifted from one gear ratio to another.To start the engine or shift the gears, the driver has to depress the clutch pedal with the purpose of disengagement the transmission from the engine. At that time, the driven members connected to the transmission input shaft are either stationary or rotating at a speed that is slower or faster than the driving members connected to the engine crankshaft. There is no spring pressure on the clutch assembly parts. So there is no friction between the driving members and driven members. As the driver lets loose the clutch pedal, spring pre ssure increases on the clutch parts. Friction between the parts also increases. The pressure exerted by the springs on the driven members is controlled by the driver through the clutch pedal and linkage. The positive engagement of the driving and driven members is made possible by the friction between the surfaces of the members. When full spring pressure is applied, the speed of the driving and driven members should be the same. At themoment, the clutch must act as a solid coupling device and transmit al l engine power to the transmission, without slipping.However, the transmission should be engaged to the engine gradually in order to operate the car smoothly and minimize torsional shock on the drive train because an engine at idle just develops little power. Otherwise, the driving members are connected with the driven members too quickly and the engine would be stalled.The flywheel is a major part of the clutch. The flywheel mounts to the engine’s crankshaft and transmits engine torque to the clutch assembly. The flywheel, when coupled with the clutch disc and pressure plate makes and breaks the flow of power from the engine to the transmission.The flywheel provides a mounting location for the clutch assembly as well. When the clutch is applied, the flyw heel transfers engine torque to the clutch disc. Because of its weight, the flywheel helps to smooth engine operation. The flywheel also has a large ring gear at its outer edge, which engages with a pinion gear on the starter motor during engine cranking.The clutch disc fits between the flywheel and the pressure plate. The clutch disc has a splined hub that fits over splines on the transmission input shaft. A splined hub has grooves that match splines on the shaft. These splines fit in the grooves. Thus, t he two parts are held together. However, back-and-forth movement of the disc on the shaft is possible. Attached to the input shaft, At disc turns at the speed of the shaft.The clutch pressure plate is generally made of cast iron. It is round and about the same diameter as the clutch disc. One side of the pressure plate is machined smooth. This side will press th e clutch disc facing are against the flywheel. The outer side has various shapes to facilitate attachment of spring and release mechanisms. The two primary types of pressure plate assemblies are coil spri ng assembly and diaphragmspring (Figure 8-3).In a coil spring clutch the pressure plate is backed by a number of coil springs and housed with them in a pressed-steel cover bolted to the flywheel. The springs push against the cover. Neither the driven plate nor the pressure plate is connected rigidly to the flywheel and both can move either towards it or away. When the clutch pedal is depressed a thrust pad riding on a carbon or ball thrust bearing i s forced towards the flywheel. Levers pivoted so that they engage with the thrust pad at one end and the pressure plate at the other end pull the pressure plate back against its springs. This releases pressure on the driven plate disconnecting the gearbox from the engine (Figure 8-4).Diaphragm spring pressure plate assemblies are widely used in most modern cars. The diaphragm spring is a single thin sheet of metal which yields when pressure is applied to it. When pressure is removed the metal springs back to its original shape. The centre portion of the diaphragm spring is slit into numerous fingers that act as release levers. When the clutch assembly rotates with the engine these weights are flung outwards by centrifugal forces and cause the levers to pre ss against the pressure plate. During disengagement of the clutch the fingers are moved forward by the release bearing. The spring pivots over the fulcrum ring and its outer rim moves away from the flywheel. The retracting spring pulls the pressure plate a way from the clutch plate thus disengaging the clutch (Figure 8-5).When engaged the release bearing and the fingers of the diaphragm spring move towards the transmission. As the diaphragm pivots over the pivot ring its outer rim forces the pressure plate against the clutch disc so that the clutch plate is engaged to the flywheel.The advantages of a diaphragm type pres sure plate assembly are its compactness, lower weight, fewer moving parts, less effort to en gage, reduces rotational imbalance by providin g a balanced force around the pressure plate and less chances of clutch slippage.The clutch pedal is connected to the disengagement mechanism either by a cable or, more com monly, by a hydraulic system. Either way, pushing the pedal down operates the dise ngagement mechanism which puts pressure on the fingers of the clutch diaphragm via a release bearing and causes the diaphragm to release the clutch plate. With a hydraulic mechanism, the clutch pedal arm operates a piston in the clutch master cylinder. Thi s forces hydraulic fluid through a pipe to the clutch release cylinder where another piston operates the clutch disengagement mechanism. The alternative is to link the clutch pedal to the disengagement mechanism by a cable.The other parts including the cl utch fork, release bearing, bell-housing, bell housing cover, and pilot bushing are needed to couple and uncouple the transmission. The clutch fork, which connects to the linkage, actually operates the clutch. The release bearing fits between the clutch fork and the pressure plate assembly. The bell housing covers the clutch assembly. The bell housing c over fastens to the bottom of the bell housing. This removable cover allows a mechanic to inspect the clutch without removing the transmission and bell housing. A pilot bushing fits into the back of th e crankshaft and holds the transmission input shaft.Torque ConverterThe BasicsJust like manual transmission cars, cars with automatic transmissions need a way to let the en gine turn while the wheels and gears in the transmission come to a stop. Manual transmission cars use a clutch, which completely disconnects the engine from the transmission. Automatic transmis sion cars use a torque converter.A torque converter is a type of fluid coupling, which allows the engine to spin somewhat independently of the transmission. If the engine is turning slowly, such as when the car is idling at a stoplight,the amount of torque passed through the torque converter is very small, so keeping the car still requires only a li ght pressure on the brake pedal.If you were to step on the gas pedal while the car is stopped, you would have to press harder on the brake to keep the car from moving. This is because when you step on the gas, the engine speeds up and pumps more fluid into the torque converter, causing more torque to be transmitted to the wheels.Inside a Torque ConverterThere are four components inside the very strong housing of the torque converter:1. Pump;2. Turbine;3. Stator;4. Transmission fluid.The housing of the torque converter is bolted to the flywheel of the engine, so it turns at what ever speed the engine is running at. The fins that make up the pump of the torque converter are at tached to the housing, so they also turn at the same speed as the engine. The cutaway below shows how everything is connected inside the torque converter (Figure 8-6).The pump inside a torque converter is a type of centrifugal pump. As it spins, fluid is flung to the outside, much as the spin cycle of a washing machine flings water and clothes to the outside of the wash tub. As fluid is flung to the outside, a vacuum is created that draws more fluid in at the center.The fluid then enters the blades of the turbine, which is connected to the transmission. The turbine causes the transmission to spin, which basically moves the car. The blades of the turbine are curved. This means that the fluid, which enters the turbine from the outside, has to change direction before it exits the center of the turbine. It is this directional change that causes the turbine to spin.The fluid exits the turbine at the center, moving in a different direction than when it entered. The fluid exits the turbine moving opposite the direction that the pump (and engine) is turning. If the fluid were allowed to hit the pump, it would slow the engine down, wasting power. This is why a torque converter has a stator.The stator resides in the very center of the torque converter. Its job is to redirect the fluid returning from the turbine before it hits the pump again. This dramatically increases the efficiency of the torque converter.The stator has a very aggressive blade design that almost completely reverses the direction of the fluid. A one-way clutch (inside the stator) connects the stator to a fixed shaft i n the transmission. Because of this arrangement, the stator cannot spin with the fluid - i tc a n s p i n o n l y i n t h e o p p o s i t ed i re c t i o n,f o r c i ng th e f l ui d t oc h a n g ed i re c t i o n a s i t h i t s t h e s t a t o r b l a d e s.Something a little bit tricky happens when the car gets moving. There is a point, around 40 mph (64 kph), at which both the pump and the turbine are spinning at almost the same speed (the pump always spins slightly faster). At this point, the fluid returns from the turbine, entering the pump already moving in the same direction as the pump, so the stator is not needed.Even though the turbine changes the direction of the fluid and flings it out the back, the fluid still ends up moving in the direction that the turbine is spinning because the turbine is spinning faster in one direction than the fluid is being pumped in the other direction. If you were standing in the back of a pickup moving at 60 mph, and you threw a ball out the back of that pickup at 40 mph, the ball would still be going forward at 20 mph. This is similar to what happens in the tur bine: The fluid is being flung out the back in one direction, but not as fast as it was going to start with in the other direction.At these speeds, the fluid actually strikes the back sides of the stator blades, causing the stator to freewheel on its one-way clutch so it doesn’t hinder the fluid moving through it.Benefits and Weak PointsIn addition to the very important job of allowing a car come to a complete stop without stalling the engine; the torque converter a ctually gives the car more torque when you accelerate out of a Stop. Modern torque converters can multiply the torque of the engine by two to three times. This effect only happens when the engine is turning much faster than the transmission.At higher speeds, the transmission catches up to the engine, eventually moving at almost the same speed. Ideally, though, the transmission would move at exactly the same speed as the engine, because this difference in speed wastes power. This is part of the reason why cars with automatic transmissions get worse gas mileage than cars with manual transmissions.To counter this effect, some cars have a torque converter with a lockup clutch. When the two halves of the torque converter get up to speed, this clutch locks them together, eliminating the slip page and improving efficiency.离合器发动机产生动力用以驱动车辆。

Automobile Brake SystemThe braking system is the most important system in cars. If the brakes fail, the result can be disastrous. Brakes are actually energy conversion devices, which convert the kinetic energy (momentum) of the vehicle into thermal energy (heat).When stepping on the brakes, the driver commands a stopping force ten times as powerful as the force that puts the car in motion. The braking system can exert thousands of pounds of pressure on each of the four brakes.Two complete independent braking systems are used on the car. They are the service brake and the parking brake.The service brake acts to slow, stop, or hold the vehicle during normal driving. They are foot-operated by the driver depressing and releasing the brake pedal. The primary purpose of the brake is to hold the vehicle stationary while it is unattended. The parking brake is mechanically operated by when a separate parking brake foot pedalor hand lever is set.The brake system is composed of the following basic components: the “master cylinder” which is located under the hood, and is directly connected to the brake pedal, converts driver foot’s mechanical pressure into hydraulic pressure. Steel “brake lines” and flexible “brake hoses” connect the master cylinder to the “slave cylinders” located at each wheel. Brake fluid, specially designed to work in extreme conditions, fills the system. “Shoes” and “pads” are pushed by the slave cylinders to contact the “drums” and “rotors” thus causing drag, which (hopefully) slows the car.The typical brake system consists of disk brakes in front and either disk or drum brakes in the rear connected by a system of tubes and hoses that link the brake at each wheel to the master cylinder (Figure).Basically, all car brakes are friction brakes. When the driver applies the brake, the control device forces brake shoes, or pads, against the rotating brake drum or disks at wheel. Friction between the shoes or pads and the drums or disks then slows or stops the wheel so that the car is braked.In most modern brake systems (see Figure 15.1), there is a fluid-filled cylinder, called master cylinder, which contains two separate sections, there is a piston in each section and both pistons are connected to a brake pedal in the driver’s compartment. When the brake is pushed down, brake fluid is sent from the master cylinder to the wheels.At the wheels, the fluid pushes shoes, or pads, against revolving drums or disks. The friction between the stationary shoes, or pads, and the revolving drums or disks slows and stops them. This slows or stops the revolving wheels, which, in turn, slow or stop the car.The brake fluid reservoir is on top of the master cylinder. Most cars today have a transparent r reservoir so that you can see the level without opening the cover. The brake fluid level will drop slightly as the brake pads wear. This is a normal condition and no cause for concern. If the level drops noticeably over ashort period of time or goes down to about two thirds full, have your brakes checked as soon as possible. Keep the reservoir covered except for the amount of time you need to fill it and never leave a cam of brake fluid uncovered. Brake fluid must maintain a very high boiling point. Exposure to air will cause the fluid to absorb moisture which will lower that boiling point.The brake fluid travels from the master cylinder to the wheels through a series of steel tubes and reinforced rubber hoses. Rubber hoses are only used in places that require flexibility, such as at the front wheels, which move up and down as well as steer. The rest of the system uses non-corrosive seamless steel tubing with special fittings at all attachment points. If a steel line requires a repair, the best procedure is to replace the compete line. If this is not practical, a line can be repaired using special splice fittings that are made for brake system repair. You must never use copper tubing to repair a brake system. They are dangerous and illegal.Drum brakes, it consists of the brake drum, an expander, pull back springs, a stationary back plate, two shoes with friction linings, and anchor pins. The stationary back plate is secured to the flange of the axle housing or to the steering knuckle. The brake drum is mounted on the wheel hub. There is a clearance between the inner surface of the drum and the shoe lining. To apply brakes, the driver pushes pedal, the expander expands the shoes and presses them to the drum. Friction between the brake drum and the friction linings brakes the wheels and the vehicle stops. To releaseAnti-lock brake systems make braking safer and more convenient, Anti-lock brake systems modulate brake system hydraulic pressure to prevent the brakes from locking and the tires from skidding on slippery pavement or during a panic stop.Anti-lock brake systems have been used on aircraft for years, and some domestic car were offered with an early form of anti-lock braking in late 1990’s. Recently, several automakers have introduced more sophisticated anti-lock system. Investigations in Europe, where anti-lock brakin g systems have been available for a decade, have led one manufacture to state that the number of traffic accidents could be reduced by seven and a half percent if all cars had anti-lock brakes. So some sources predict that all cars will offer anti-lock brakes to improve the safety of the car.Anti-lock systems modulate brake application force several times per second to hold the tires at a controlled amount of slip; all systems accomplish this in basically the same way. One or more speed sensors generate alternating current signal whose frequency increases with the wheel rotational speed. An electronic control unit continuously monitors these signals and if the frequency of a signal drops too rapidly indicating that a wheel is about to lock, the control unit instructs a modulating device to reduce hydraulic pressure to the brake at the affected wheel. When sensor signals indicate the wheel is again rotating normally, the control unit allows increased hydraulic pressure to the brake. This release-apply cycle occurs several time per second to “pump” the brakes like a driver might but a t a much faster rate.In addition to their basic operation, anti-lock systems have two other things in common. First, they do not operate until the brakes are applied with enough force to lock or nearly lock a wheel. At all other times, the system stands ready to function but does not interfere with normal braking. Second, if the anti-lock system fail in any way, the brakes continue to operate without anti-lock capability. A warning light on the instrument panel alerts the driver when a problem exists in the anti-lock system.The current Bosch component Anti-lock Braking System (ABSⅡ), is a second generation design wildly used by European automakers such as BWM,Mercedes-Benz and Porsche. ABSⅡsystem consists of : four wheel speed sensor, electronic control unit and modulator assembly.A speed sensor is fitted at each wheel sends signals about wheel rotation to control unit. Each speed sensor consists of a sensor unit and a gear wheel. The front sensor mounts to the steering knuckle and its gear wheel is pressed onto the stub axle that rotates with the wheel. The rear sensor mounts the rear suspension member and its gear wheel is pressed onto the axle. The sensor itself is a winding with a magnetic core. The core creates a magnetic field around the winding, and as the teeth of the gear wheel move through this field, an alternating current is induced in the winding. The control unit monitors the rate o change in this frequency to determine impending brake lockup.The control unit’s function can be divided into three parts: signal processing, logic and safety circuitry. The signal processing section is the converter that receives the alternating current signals form the speed sensors and converts them into digital form for the logic section. The logic section then analyzes the digitized signals to calculate any brake pressure changes needed. If impending lockup is sensed, the logic section sends commands to the modulator assembly.Modulator assemblyThe hydraulic modulator assembly regulates pressure to the wheel brakes when it receives commands from the control utuit. The modulator assembly can maintain or reduce pressure over the level it receives from the master cylinder, it also can never apply the brakes by itself. The modulator assembly consists of three high-speed electric solenoid valves, two fluid reservoirs and a turn delivery pump equipped with inlet and outlet check valves. The modulator electrical connector and controlling relays are concealed under a plastic cover of the assembly.Each front wheel is served by electric solenoid valve modulated independently by the control unit. The rear brakes are served by a single solenoid valve and modulated together using the select-low principle. During anti-braking system operation, the control unit cycles the solenoid valves to either hold or release pressure the brake lines. When pressure is released from the brake lines during anti-braking operation, it is routed to a fluid reservoir. There is one reservoir for the front brake circuit. The reservoirs are low-pressure accumulators that store fluid under slight spring pressure until the return delivery pump can return the fluid through the brake lines to the master cylinder.汽车制动系统制动系统是汽车中最重要的系统。

CLUTCHThe engine produces the power to drive the vehicle. The drive line or drive train transfers the power of the engine to the wheels. The drive train consists of the parts from the back of the flywh eel to the wheels. These parts include the clutch, the transmission, the drive shaft, and the final drive assembly.The clutch which includes the flywheel, clutch disc, pressure plate, springs, pressure plate cover and the linkage necessary to operate the clutch is a rotating mechanism between the engine and the transmission. It operates through friction which comes from contact between the parts. That is the reason why the clutch is called a friction mechanism. After engagement, the clutch must continue to transmit all the engine torque to the transmission depending on the friction without slippage. The clutch is also used to disengage the engine from the drive train whenever the gears in the transmission are being shifted from one gear ratio to another.To start the engine or shift the gears, the driver has t o depress the clutch pedal with the purpose of disengagement the transmission from the engine. At that time, the driven members connected to the transmission input shaft are either stationary or rotating at a speed that is slower or faster than the driving members connected to the engine crankshaft. There is no spring pressure on the clutch assembly parts. So there is no friction between the driving members and driven members. As the driver lets loose the clutch pedal, spring pressure increases on the clutch parts. Friction between the parts also increases. The pressure exerted by the springs on the driven members is controlled by the driver through the clutch pedal and linkage. The positive engagement of the driving and driven members is made possible by the friction between the surfaces of the members. When full spring pressure is applied, the speed of the driving and driven members should be the same. At the moment, the clutch must act as a solid coupling device and transmit allengine power to the transmission, without slipping.However, the transmission should be engaged to the engine gradually in order to operate the car smoothly and minimize torsional shock on the drive train because an engine at idle just develops little power. Otherwise, the driving members are connected with the driven members too quickly and the engine would be stalled.The flywheel is a major part of the clutch. The flywheel mounts to the engine’s crankshaft and transmits engine torque to the clutch assembly. The flywheel, when co upled with the clutch disc and pressure plate makes and breaks the flow of power from the engine to the transmission.The flywheel provides a mounting location for the clutch assembly as well. When the clutch is applied, the flywheel transfers engine torque to the clutch disc. Because of its weight, the flywheel helps to smooth engine operation. The flywheel also has a large ring gear at its outer edge, which engages with a pinion gear on the starter motor during engine cranking.The clutch disc fits between the flywheel and the pressure plate. The clutch disc has a splined hub that fits over splines on the transmission input shaft. A splined hub has grooves that match splines on the shaft. These splines fit in the grooves. Thus, the two parts are held together. However, back-and-forth movement of the disc on the shaft is possible. Attached to the input shaft, At disc turns at the speed of the shaft.The clutch pressure plate is generally made of cast iron. It is round and about the same diameter as the clutch disc. One side of the pressure plate is machined smooth. This side will press th e clutch disc facing are against the flywheel. The outer side has various shapes to facilitate attachment of spring and release mechanisms. The two primary types of pressure plate assemblies are coil spring assembly and diaphragm spring.In a coil spring clutch the pressure plate is backed by a number of coil springs and housed with them in a pressed-steel cover bolted to the flywheel. The springs push against the cover. Neith er the driven plate nor the pressure plate is connected rigidly to the flywheel and both can move either towards it or away. When the clutch pedal is depressed a thrust pad riding on a carbon or ball thrust bearing is forced towards the flywheel. Levers pivoted so that they engage with the thrust pad at one end and the pressure plate at the other end pull the pressure plate back against its springs. This releases pressure on the driven plate disconnecting the gearbox from the engine.Diaphragm spring pressure plate assemblies are widely used in most modern cars. The diaphragm spring is a single thin sheet of metal which yields when pressure is applied to it. When pressure is removed the metal springs back to its original shape. The centre portion of the diaphragm spring is slit into numerous fingers that act as release levers. When the clutch assembly rotates with the engine these weights are flung outwards by centrifugal forces and cause the levers to press against the pressure plate. During disengagement o f the clutch the fingers are moved forward by the release bearing. The spring pivots over the fulcrum ring and its outer rim moves away from the flywheel. The retracting spring pulls the pressure plate away from the clutch plate thus disengaging the clutch.When engaged the release bearing and the fingers of the diaphragm spring move towards the transmission. As the diaphragm pivots over the pivot ring its outer rim forces the pressure plate against the clutch disc so that the clutch plate is engaged to the flywheel.The advantages of a diaphragm type pres sure plate assembly are its compactness, lower weight, fewer moving parts, less effort to en gage, reduces rotational imbalance by providing a balanced force around the pressure plate and less chances of clutch slippage.The clutch pedal is connected to the disengagement mechanismeither by a cable or, more com monly, by a hydraulic system. Either way, pushing the pedal down operates the disengagement mechanism which puts pressure on the fingers of the clut ch diaphragm via a release bearing and causes the diaphragm to release the clutch plate. With a hydraulic mechanism, the clutch pedal arm operates a piston in the clutch master cylinder. This forces hydraulic fluid through a pipe to the clutch release cylinder where another piston operates the clutch disengagement mechanism. The alternative is to link the clutch pedal to the disengagement mechanism by a cable.The other parts including the clutch fork, release bearing, bell-housing, bell housing cover, and pilot bushing are needed to couple and uncouple the transmission. The clutch fork, which connects to the linkage, actually operates the clutch. The release bearing fits between the clutch fork and the pressure plate assembly. The bell housing covers the clutch assembly. The bell housing cover fastens to the bottom of the bell housing. This removable cover allows a mechanic to inspect the clutch without removing the transmission and bell housing. A pilot bushing fits into the back of th e crankshaft and holds the transmission input shaft.Torque ConverterThe BasicsJust like manual transmission cars, cars with automatic transmissions need a way to let the en gine turn while the wheels and gears in the transmission come to a stop. Manual transmission cars use a clutch, which completely disconnects the engine from the transmission. Automatic transmis sion cars use a torque converter.A torque converter is a type of fluid coupling, which allows the engine to spin somewhat independently of the transmission. If th e engine is turning slowly, such as when the car is idling at a stoplight, the amount of torque passed through the torque converter is very small,so keeping the car still requires only a light pressure on the brake pedal.If you were to step on the gas pe dal while the car is stopped, you would have to press harder on the brake to keep the car from moving. This is because when you step on the gas, the engine speeds up and pumps more fluid into the torque converter, causing more torque to be transmitted to the wheels.Inside a Torque ConverterThere are four components inside the very strong housing of the torque converter:1. Pump;2. Turbine;3. Stator;4. Transmission fluid.The housing of the torque converter is bolted to the flywheel of the engine, so it turns at whatever speed the engine is running at. The fins that make up the pump of the torque converter are at tached to the housing, so they also turn at the same speed as the engine.The pump inside a torque converter is a type of centrifugal pump. As it spins, fluid is flung to the outside, much as the spin cycle of a washing machine flings water and clothes to the outside of the wash tub. As fluid is flung to the outside, a vacuum is created that draws more fluid in at the center.The fluid then enters the blades of the turbine, which is connected to the transmission. The turbine causes the transmission to spin, which basically moves the car. The blades of the turbine are curved. This means that the fluid, which enters the turbine from the outside, has to change direction before it exits the center of the turbine. It is this directional change that causes the turbine to spin.The fluid exits the turbine at the center, moving in a different direction than when it entered. The fluid exits the turbin e movingopposite the direction that the pump (and engine) is turning. If the fluid were allowed to hit the pump, it would slow the engine down, wasting power. This is why a torque converter has a stator.The stator resides in the very center of the torque converter. Its job is to redirect the fluid returning from the turbine before it hits the pump again. This dramatically increases the efficiency of the torque converter.The stator has a very aggressive blade design that almost completely reverses the direction of the fluid. A one-way clutch (inside the stator) connects the stator to a fixed shaft in the transmission. Because of this arrangement, the stator cannot spin with the fluid - i tc a n s p i n o n l y i n t h e o p p o s i t ed i re c t i o n,f o r c i ng th e f l ui d t oc h a n g ed i re c t i o n a s i t h i t s t h e s t a t o r b l a d e s.Something a little bit tricky happens when the car gets moving. There is a point, around 40 mph (64 kph), at which both the pump and the turbine are spinning at almost the same speed (the pump always spins slightly faster). At this point, the fluid returns from the turbine, entering the pump already moving in the same direction as the pump, so the stator is not needed.Even though the turbine changes the direction of the fluid and flings it out the back, the fluid still ends up moving in the direction that the turbine is spinning because the turbine is spinning faster in one direction than the fluid is being pumped in the other direction. If you were standing in the back of a pickup moving at 60 mph, and you threw a ball out the back of that pickup at 40 mph, the ball would still be going forward at 20 mph. This is similar to what happens in the tur bine: The fluid is being flung out the back in one direction, but not as fast as it was going to start with in the other direction.At these speeds, the fluid actually strikes the back sides of thestator blades, causing the stator to freewheel on its one-way clutch so it doesn’t hinder the fluid moving through it.Benefits and Weak PointsIn addition to the very important job of allowing a car come to a complete stop without stalling the engine; the torque converter actually gives the car more torque when you accelerate out of a Stop. Modern torque converters can multiply the torque of the engine by two to three times. This effect only happens when the engine is turning much faster than the transmission.At higher speeds, the transmission catches up to the engine, eventually moving at almost the same speed. Ideally, though, the transmission would move at exactly the same sp eed as the engine, because this difference in speed wastes power. This is part of the reason why cars with automatic transmissions get worse gas mileage than cars with manual transmissions.To counter this effect, some cars have a torque converter with a lockup clutch. When the two halves of the torque converter get up to speed, this clutch locks them together, eliminating the slip page and improving efficiency.。

附录1Clutch of new developments in technologyAbstract: in recent years car design and manufacturing technology progress for all to see. In order to further improve product performance, prolong service life, common mechanical clutch technology is also produced a remarkable change. No matter from structural characteristics, product process performance, or control technology, mechanical clutch of technological progress in some extent reflects the development of design concepts, and possible technology trends in the future.Keywords: clutch; Technology development1, introductionIn car technology rapid development today, especially with the electronic technology in cars, the extensive application of vehicle drivetrain is had great progress, as an important part of the transmission of the clutch assembly force transmission, the burden of reducing vibration and prevent system overload very important role. To make sure that the power transmission and reliable, separate thoroughly, combined with soft, damping good, small volume, light weight, easy, long service life, making the clutch product either cash from the performance, structure, or manufacturing mode and control, in the occurrence of a lot of change. They greatly optimized clutch all aspects of performance, to some extent look, these changes are also reflected the development direction of the clutch.2, engine flywheel new structureAs one of the flywheel storage components engine, is also part of the clutch initiative. As the car transmission belong to multi-freedom torsional vibration system, whether the incentive and transmission system, or the associated force vibration type and the coupling vibration with other statements are very complex. In order to adapt to car driving conditions of vibration and noise reduction of reducing the need, making cars, ride comfort the role of torsional shock absorber is extremely important. It should be able to adjust the system inherent frequency, the system mainly low-order resonance critical speed remove common, also need to use speed range, still need to decrease amplitude damping of transmission system can reduce idle noise, ease the impact of the special case load. Previous clutch platen set on by a twist of shock absorber, decorate a space place is restricted, shock absorber work reverse Angle small, torsion stiffness big, capacity small, springs, and therefore not guarantee the intensity of vibration reduction is limited.In recent years, the emergence of a reverse damping characteristics and performance to price are ideal double quality flywheel structure. The flywheel by primary flywheel, reverse shock absorber and subprime flywheel composition, among them, the primary flywheel on one hand we should provide for the shock absorber and clutch installation space, on the other hand also with appropriate rotational inertia insure a car, and reduce passed back starting the amplitude. Generally, double quality flywheel adopts with circular arc shape along the spiral spring primary flywheel outer periphery decorate way, in limited circumstances decorate a space, the arrangement to obtain larger primary flywheel rotational inertia. The inertia and the clutch after brief increase engine speed fluctuation of related parts, shorten their service life. To avoid the above phenomenon, often need additional Settings special damping, such, can increase the difficulty and cost of product development. Because the engine of the car front front drive type of transmission installation space is limited, so this kind of structure in FF type cars to the promotion. Meanwhile, this kind of decorate spring along the circumference, due to high speed double quality flywheel centrifugal role, spring wear when, or even produces broken.Using radial layout springs can improve the double quality flywheel of the above mentioned products defect. It consists of primary flywheel, 3 ~ 4 springs box, damping dish and subprime flywheel composition. Because the suspension spring box of radial layout, the primary flywheel rely on four posts the muscles of rib takes form enough flywheel stiffness and produced similar with traditional flywheel inertia.This kind is decorated in a small space to with smaller quality to gain the maximum rotation inertia, help reduce the assembly structure, the axial dimensions for subprime flywheel and clutch decorate a space make more. Its damping device by a wear-resisting plastic gasket, a belt of steel plate and a slot disc spring washers constitute, they set in damping plate, rely on damping disc hole flanging positioning and compaction, the damping disk with primary flywheel riveted by the subprime, plastic gasket flywheel slot drive. Practice proves that the double quality than ever, this structure can be the flywheel in a limited space get quite good vibration reduction.Engine for the job, usually by the flywheel, inertia and the clutch clutch disc provides together. The ideal flywheel structure should be to offer the same, and ensure enough inertia structure stiffness premise to minimize the flywheel quality, stamping steel way to replace traditional casting can obtain the flywheel ways to produce the effect. Change the pressure by casting lron yuntechtc ring, start toothed ring and steel blunt system drivers disk of three parts. In the ring gear driving plate welding, pressure rings and drivers disk riveting, pressure ring of moment of inertia of the subject constitutes a flywheel, and provide for the clutch friction surface and heat conduction. Drivers disk improve enough flywheel stiffness, and using laser welding and clutch cover, this is connected to this structure forms of changescan be compared to traditional iron flywheel reduce quality 5% ~ 10%. USES the steel plate stamping type flywheel, and clutch cover and flywheel connections between after replacing bolt connection with welding, reducing the number and machinery manufactured parts, which reduces the production cost. The foregoing radial layout springs double quality can use this stamping yuntechtc for structure form, reducing axial dimensions[]17.3, clutch discClutch platen design of the main contradiction is facing, on one hand, hope to have as played platen diameter, in order to obtain the good preach torsional characteristic, reducing friction slices wear quantity and improve the service life, on the other hand, hope the decrease of the platen as possible, so as to shorten the rotational inertia of the variable transmission shift, ensure the synchronization time of smooth, transmission clutch platen ontology conscious drops, and therefore made wavy often difficult to coordinate the contradiction. When using triangle groove platen ontology structure, while keeping the original way wavy platen ontology has the axial elastic properties at the same time, because of its large on the plane can be formed, enough to make its and friction slices adhesive is used to connect the replacement of traditional riveting, so that in friction chip will not need the thickness of the steel back to reserve rivet, so clutch friction slices thickness, which can reduce the platen axial dimensions, and can be reduced by 10% of inertia can reduce nearly 25%. In other words, keep the premise of inertia unchanged, possible will platen diameter increases, so can the arrangement for torsional shock absorber, let a space when damper spring job increase, the rigidity of the shock absorber in diameter can be reduced greatly, increasing the space for setting also provides an ideal damping components fundamental conditions. On the other hand, because platen diameter increases, the optimization of diaphragm spring separation means it can obviously reduce leverage than the load bearing separation.Using triangle groove platen ontology and friction piece of adhesive technology, still can make clutch friction slices surface pressure distribution, and more uniform can improve the service life of friction slices.4, clutch diaphragm springUsing the diaphragm spring of a nonlinear elastic properties, can increase the ability of clutch abrasion resistance. Usually, can pass the clutch when installation, adjustment diaphragm spring axial position, to keep the spring of compaction force, but due to the manufacturing process of previous position error is quite large, so often wasted spring this portion of elastic energy, enables the abrasion resistance ability get full play. When the clutch cover and flywheel connection with the above welding way to finish, the clutch assembly may allow such position when the adjustment, thus, the corresponding clutchscratch-resistant ability can improve the 4% ~ 30%.To improve the ability to change its antiwear properties, but also can the diaphragm spring is reinforced by controlling method of separation means and the rib disc supporting ring approach to getting.[]175, clutch control systemAutomatic transmission in cars growing popularity of today, due to its lack of transmission efficiency of cars, and motorists feel lost control, makes mechanical clutch still has wide market. Along with the computer technology and the rapid development of modern control technology has to clutch may reality automatic control, automatic clutch management system (CMC) is the product of this idea. The driver speaking, clutch automatic control system is that it is the most obvious advantage of cancelled the clutch pedal, thus improve the driving comfort, whether in the city the frequent change of traffic environment, or in the ramp, its advantages are started is quite clear. Meanwhile, in order to reduce the transmission low noise and vibration, CMC is likely to clutch real-time control of sliding, all these can improve automobile driving safety. Although the automatic transmission can also play the same role in price, but the CMC, fuel efficiency, engine braking and rapid response, etc but again the obvious advantage. In addition, it has no peristalsis phenomenon, and can make control shift timing. Drivers On the other hand, for car itself, because the CMC reduced because the actual driving quite frequent false operation produces drivetrain stress, therefore, can reduce the transmission and its transmission parts design dimensions, in general driving conditions, electronic control ensures the accuracy and speed than artificially operation circumstance clutch of wear small, long service life.CMC consists of three parts: namely is used to identify the driver intention and the clutch, the transmission working state of sensors,Clutch actuators and electronic control unit, drivers shift HuanDangGan movements and intention through the release of the accelerator pedal to identify, this requires signal judge strategy and control must be very quick, to avoid the feeling of driver produce shift block, when pilots inadvertently tinkering with the transmission system when rod may not false action. In addition, the CMC through the engine speed, the transmission input shaft speed and throttle position signal to clutch slip for mind control, which can eliminate the car driving common vibration and noise. Such as a limit control to prevent slip in 1 and 2, block small throttle low-speed driving, the car slightly tilted forward, generating about 1Hz very uncomfortable zitterbewegung, through in the clutch of transient torsional direction change quickly, to eliminate the separation clutch in clutch under the condition of incomplete combinations, when pilots alternate relaxation and trample accelerator pedal, because thetransmission torque change to the sharp produced recoiling sickening crash; or depressing Through the precise relative slip between 50 ~ 100rpm control, can eliminate in high-grade, high and low speed conditions when the engine driving torque values in the passenger cabin can smell the low-frequency resonance produced, and when the transmission in 2 ~ 3 block, engine speed 12 ~ 2500rpm and high load, the transmission possible beats noise; Through the separation clutch, convenient when the elimination of the idle will clutch and neutral transmission combine, engine torque peak in the transmission of idle speed noise produced. The key is to prevent vibration noise sensitivity and accuracy, this system requirements system has high control ability, rely on modern computer and hydraulic control technology has been possible this some.[]186, closingBy adopting a new design concept, can make clutch axial dimensions is much shorter, platen diameter increases, power transmission more reliable, clutch capacity increases, separation bearing load is reduced, torsion vibration reduction improve, processing manufacturing easier, lower cost, service life can be extended 50% and than before can be expected, along with the automatic control technology mature gradually perfect, clutch control mode will also continue to rapid development.附录 2汽车离合器技术的新发展摘要：近年来汽车设计和制造技术的进步有目共睹。

离合器工作原理英文翻译The working principle of a clutch can be explained as follows:A clutch is a mechanical device that is primarily used in vehicles to engage and disengage power transmission between the engine and the gearbox. Its main function is to temporarily disconnect the engine from the transmission system when the driver shifts gears or when the vehicle comes to a stop.The clutch assembly consists of several components, including a clutch disc, pressure plate, flywheel, release bearing, and clutch pedal. When the clutch pedal is pressed, it activates the release mechanism, which causes the clutch disc to be released from the flywheel. This disengagement interrupts the power flow from the engine to the gearbox, allowing the driver to smoothly shift gears.The clutch disc is the main component responsible for transmitting torque from the engine to the transmission system. It consists of a splined hub, driven plate, and friction linings on both sides. When the clutch pedal is released, the pressure plate presses the clutch disc against the flywheel, creating a frictional force that securely connects the engine to the gearbox.The friction linings on the clutch disc are made of high-friction materials such as organic material or ceramic. These linings enable the transmission of power while preventing slipping during engagement. Over time, due to wear and tear, these linings may need to be replaced to ensure the proper functioning of the clutch. In summary, a clutch operates by using a combination ofmechanical components to engage or disengage the power transmission between the engine and the gearbox. This mechanism enables smooth shifting of gears and efficient power transfer in vehicles.。

附录How Does the Clutch WorkThe clutch is a device to engage and disengage power from the engine, allowing the vehicle to stop and start.A pressure plate or “driving member” is bolted to the engine flywheel, and a clutch plate or “driven member” is loc ated between the flywheel and the pressure plate. The clutch plate is spline to the shaft extending from the transmission to the flywheel, commonly called a clutch shaft or input shaft. When the clutch and pressure plates are locked together by friction, the clutch shaft rotates with the engine crankshaft. Power is transferred from the engine to the transmission, where it is routed through different gear rations to obtain the best speed and power to start and keep the vehicle moving.The flywheel is located at the rear of the engine and is bolted to the crankshaft. It helps absorb power impulses, resulting in a smoothly-idling engine and provides momentum to carry the engine through its operating cycle. The rear surface of the flywheel is machined flat and the clutch components are attached to it. The driving member is commonly called the pressure plate. It is bolted to the engine flywheel and its main purpose is to exert pressure against the clutch plate, holding the plate tight against the flywheel and allowing the power to flow from the engine to the transmission. It must also be capable of interrupting the power flow by releasing the pressure on the clutch plate. This allows the clutch plate to stop rotating while the flywheel and pressure plate continues to rotate.The pressure plate consist of a heavy metal plate, coil springs or diaphragm spring, release levers (fingers), and a cover. When coil springs are used, they are evenly spaced around the metal plate and located between the plate and the metal cover. This places an even pressure against the plate, which in turn presses the clutch plate tight against the flywheel. The cover is bolted tightly to the flywheel and the metal pate is movable, due to internal linkages. The coil springs are arranged to exert direct or indirect tension on the metal plate, depending upon the manufacturer’s design. Three release levers (fingers), evenly spaced around the cover, are used on most pressure plates to release the holding pressure of the springs on the clutch plate, allowing it to disengage the power flow.When a diaphragm spring is used instead of coil springs, the internal linkage is necessarily different to provide an “over-center” action to release the clutch plate from the flywheel. Its operation can be compared to the operation of an oilcan. When depressing the slightly curved metal on the bottom of the oilcan, it goes over-center and gives out a loud “clicking” noise; when released, the noise is again heard as the metal returns to its originalposition. A click is not heard in the clutch operation, but the action of the diaphragm spring is the same as the oilcan.The clutch plate or driven member consists of a round metal plate attached to a splined hub. The outer portion of the round plate is covered with a friction material of molded or woven asbestos and is riveted or bonded to the plate. The thickness of the clutch plate and /or facings may be warped to give a softer clutch engagement. Coil springs are often installed in the hub to help provide a cushion against the twisting force of engagement. The splined hub is mated to (and turns) a splined transmission shaft when the clutch is engaged.The release (throw out) bearing is usually a ball bearing unit, mounted on a sleeve, and attached to the release or throw out lever. Its purpose is to apply pressure to the diaphragm spring or release levers in the pressure plate. When the clutch pedal is depressed, the pressure of the release bearing or lever actuates the internal linkages of the pressure plate, releasing the clutch plate and interrupting the power flow. The release bearing is not in constant contract with the pressure plate. A linkage adjustment clearance should be maintained.The clutch pedal provides mechanical means for the driver to control the engagement and disengagement of the clutch. The pedal is connected mechanically to either a cable or rods, which are directly connected to the release bearing lever.When the clutch pedal is depressed, the linkage moves the release bearing lever. The release lever is attached at the opposite end to a release bearing which straddles the transmission clutch shaft, and presses inward on the pressure plate gingers or the diaphragm spring. This inward pressure acts upon the fingers and internal linkage of the pressure plate and allows the clutch plate to move away from the flywheel, interrupting the flow of power.While the clutch pedal is depressed and the power flow interrupted, the transmission can be shifted in to any gear. The clutch pedal is slowly released to gradually move the clutch pate toward the flywheels under pressure of the pressure plate springs. The friction between the clutch plate and flywheel becomes greater as the pedal is released and the engine speed increased. Once the vehicle is moving, the need for clutch slippage is lessened, and the clutch pedal can be fully released.Coordination between the clutch pedal and accelerator is important to avoid engine stalling, shock to the driveline components and excessive clutch slippage and overheating.离合器如何工作离合器是传递和分离发动机动力的装置，实现车辆的停车和启动。

附录 AClutch between engine and transmission installed in the car to travel from the start the whole process, often need to use the clutch. Its role is to make the engine and transmission can be gradually between the joint, thus ensuring a smooth start car; temporarily cut off the link between the engine and transmission to shift at the time of shift and reduce the impact; When the car when emergency braking from Separate role in preventing the transmission and other drive system overload, play a protective role.Clutch similar to the switch, splice or break away from the power transmission and, accordingly, have any form of auto clutch, but the form is different.By the friction plate clutch, springs, pressure plate and the power output shaft composed, arranged between the engine and gearbox, the engine flywheel to the torque is passed to the stored transmission, to ensure that vehicles in different driving conditions passed to the driver Wheel driving force and the right amount of torque, is the scope of the powertrain. In the half-time of linkage, clutch and power input power output allowed speed difference, that is, the speed error to achieve through its transfer an appropriate amount of power. Clutch is divided into three work status, ie the clutch all connections, some of the half clutch linkage and the clutch is not linked.When a vehicle in normal driving, the pressure plate is jammed against the friction plate on the flywheel, pressure plate and friction plate at this time the friction between the largest between the input shaft and output shaft remained relatively static friction, both the same speed . When the vehicle is started, the driver depresses the clutch, clutch pedal movement by pulling back pressure plate, which is the separation of the pressure plate and friction disc, pressure plate and flywheel at this time no contact, but also the relative friction does not exist. Last one, that is, half of the clutch linkage status. At this point, the pressure plate and friction disc friction less than the full-linked state. Clutch pressure plate and flywheel friction plate on the sliding friction between the state. Flywheel speed is greater than the output shaft speed, transmission out of the power from the flywheel to the transmission part of the pass. Between the engine and driving wheels at this time is equivalent to a soft connection status.In general, the clutch and the shift in the vehicle when starting to play a role, this time a transmission shaft and the speed difference between the two shafts, engine power must be cut with a shaft after the synchronizer can be very good a shaft speed will be kept synchronized with the second axis, gear hanging up after, and then through the clutch shaft and the engine power will be a combination of the power continue to be transmitted. In the clutch, there is an essential buffer device, which consists of two similar to the flywheel with the disc, the disc hit a rectangular groove, the groove arrangement of the spring, in the face of fierce shock between the two disc springs between the elastic effect, buffer external stimuli. Effective protection of the engine and clutch. Various parts of the clutch, pressure plate spring strength, friction coefficient of friction plate, clutch diameter, location, and the clutch friction disc clutch performance is to determine the number of key factors, the greater the stiffness of the spring, the higher the friction coefficient of friction plates, the larger the diameter of the clutch, clutch performance, the better.附录 B离合器安装在发动机与变速器之间，汽车从启动到行驶的整个过程中，经常需要使用离合器。

附录How Clutches WorkIf you drive a manual transmission car, you may be surprised to find out that it has more than one clutch. And it turns out that folks with automatic transmission cars have clutches, too. In fact, there are clutches in many things you probably see or use every day: Many cordless drills have a clutch, chain saws have a centrifugal clutch and even some yo-yos have a clutch.CIn!cp I山g?e CgIIeL入D!g?Lg山 o\ cgL 2poM!u? cIn!cp Iocg!!ou. eee 山oLe cIn!cp !山g?e2In this article, you'll learn why you need a clutch, how the clutch in your car works and find out some interesting, and perhaps surprising, places where clutches can be found. Clutches are useful in devices that have two rotating shafts. In these devices, one of the shafts is typically driven by a motor or pulley, and the other shaft drives another device. In a drill, for instance, one shaft is driven by a motor and the other drives a drill chuck. The clutch connects the two shafts so that they can either be locked together and spin at the same speed,or be decoupled and spin at different speeds.In a car,you need a clutch because the engine spins all the time,but the car's wheels do not. In order for a car to stop without killing the engine, the wheels need to be disconnectedf rom the engine somehow. The clutch allows us to smoothly engage a spinning engine to a non-spinning transmission by controlling the slippage between them.To understand how a clutch works, it helps to know a little bit about friction, which is a measure of how hard it is to slide one object over another. Friction is caused by the peaks and valleys that are part of every surface -- even very smooth surfaces still have microscopic peaks and valleys. The larger these peaks and valleys are, the harder it is to slide the object. You can learn more about friction in How Brakes Work.A clutch works because of friction between a clutch plate and a flywheel. We'll look at how these parts work together in the next section.Fly Wheels,Clutch Plates and FrictionIn a car’s clutch, a flywheel connects to the engine, and a clutch plate connects to the transmission. You can see what this looks like in the figure below.When your foot is off the pedal, the springs push the pressure plate against the clutch disc, which in turn presses against the flywheel. This locks the engine to the transmission input shaft, causing them to spin at the same speed.Pressure plateThe amount of force the clutch can hold depends on the friction between the clutch plate and the flywheel, and how much force the spring puts on the pressure plate. The friction force in the clutch works just like the blocks described in the friction section of How Brakes Work, except that the spring presses on the clutch plate instead of weight pressing the block into the ground.W h en the clutch pedal is pressed, a cable or hydraulic piston pushes on the release fork, which presses the throw-out bearing against the middle of the diaphragm spring. As the middle of the diaphragm spring is pushed in, a series of pins near the outside of the spring causes the spring to pull the pressure plate away from the clutch disc (see below). This r eleases the clutch from the spinning engine.Common ProblemsFrom the 1950s to the 1970s, you could count on getting between 50,000 and 70,000 miles from your car's clutch. Clutches can now last for more than 80,000 miles if you use them gently and maintain them well. If not cared for, clutches can start to break down at 35,000 miles. Trucks that are consistently overloaded or that frequently tow heavy loads can also have problems with relatively new clutches.Photo courtesy Carolina MustangClutch plateThe clutch only wears while the clutch disc and the flywheel are spinning at different speeds. When they are locked together, the friction material is held tightly against the flywheel, and they spin in sync. It's only when the clutch disc is slipping against the flywheel that wearing occurs. So, if you are the type of driver who slips the clutch a lot, you'll wear out your clutch a lot faster.Sometimes the problem is not with slipping, but with sticking. If your clutch won't release properly, it will continue to turn the input shaft. This can cause grinding, or completely p revent your car from going into gear. Some common reasons a clutch may stick are: Broken or stretched clutch cable - The cable needs the right amount of tension to push and pull effectively.Leaky or defective slave and/or master clutch cylinders - Leaks keep the cylinders from building the necessary amount of pressure.Air in the hydraulic line - Air affects the hydraulics by taking up space the fluid needs to build pressure.Misadjusted linkage - When your foot hits the pedal, the linkage transmits the wrong amount of force.Mismatched clutch components - Not all aftermarket parts work with your clutch.depress fully. If you have to press hard on the pedal, there may be something wrong. Sticking or binding in the pedal linkage, cable, cross shaft, or pivot ball are common causes. S o metimes a blockage or worn seals in the hydraulic system can also cause a hard clutch. Another problem associated with clutches is a worn throw-out bearing, sometimes called a clutch release bearing. This bearing applies force to the fingers of the spinning pressure plate to release the clutch.If you hear a rumbling sound when the clutch engages,you might have a problem with the throw-out.Types of ClutchesThere are many other types of clutches in your car and in your garage.An automatic transmission contains several clutches. These clutches engage and disengage various sets of planetary gears. Each clutch is put into motion using pressurized hydraulic fluid. When the pressure drops, springs cause the clutch to release. Evenly spacedridges, called splines, line the inside and outside of the clutch to lock into the gears and the clutch housing. You can read more about these clutches in How Automatic Transmissions Work.An air conditioning, compressor in a car has an electromagnetic clutch. This allows the compressor to shut off even while the engine is running. When current flows through a magnetic coil in the clutch, the clutch engages. As soon as the current stops, such as when you turn off your air conditioning, the clutch disengages.Most cars that have an engine-driven cooling fan have a thermostatically controlled viscous clutch -- the temperature of the fluid actually drives the clutch. This clutch is positioned at the hub of the fan, in the airflow coming through the radiator. This type of clutch is a lot like the viscous coupling sometimes found in all-wheel drive cars. The fluid in the clutch gets thicker as it heats up, causing the fan to spin faster to catch up with the engine rotation. When the car is cold, the fluid in the clutch remains cold and the fan spins s lowly, allowing the engine to quickly warm up to its proper operating temperature.Many cars have limited slip differentials or viscous couplings, both of which use clutches to help increase traction. When your car turns, one wheel spins faster than the other, which makes the car hard to handle. The slip differential makes up for that with the help of its clutch. When one wheel spins faster than the others, the clutch engages to slow it down and match the other three. Driving over puddles of water or patches of ice can also spin your wheels. You can learn more about differentials and viscous couplings in How Differentials Work.Gas-powered chain saws and weed eaters have centrifugal clutches, so that the chains or strings can stop spinning without you having to turn off the engine. These clutches work automatically through the use of centrifugal force. The input is connected to the engine crankshaft. The output can drive a chain, belt or shaft. As the rotations per minute increase, w eighted arms swing out and force the clutch to engage. Centrifugal clutches are also often found in lawn mowers, go-karts, mopeds and mini-bikes. Even some yo-yos are m anufactured with centrifugal clutches.C lu tches are valuable and necessary to a number of applications. For more information on clutches and related topics, check out the links on the following 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。

Automobile Brake System汽车制动系统The braking system is the most important system in cars. If the brakes fail, the result can be disastrous. Brakes are actually energy conversion devices, which convert the kinetic energy (momentum) of the vehicle into thermal energy (heat).When stepping on the brakes, the driver commands a stopping force ten times as powerful as the force that puts the car in motion. The braking system can exert thousands of pounds of pressure on each of the four brakes.Two complete independent braking systems are used on the car. They are the service brake and the parking brake.The service brake acts to slow, stop, or hold the vehicle during normal driving. They are foot-operated by the driver depressing and releasing the brake pedal. The primary purpose of the brake is to hold the vehicle stationary while it is unattended. The parking brake is mechanically operated by when a separate parking brake foot pedalor hand lever is set.The brake system is composed of the following basic components: the “master cylinder” which is located under the hood, and is directly connected to the brake pedal, converts driver foot’s mechanical pressure into hydraulic pressure. Steel “brake lines” and flexible “brake hoses” connect the master cylinder to the “slave cylinders” located at each wheel. Brake fluid, specially designed to work in extreme conditions, fills the system. “Shoes” and “pads” are pushed by the slave cylinders to contact the “drums” and “rotors” thus causing drag, which (hopefully) slows the c ar.The typical brake system consists of disk brakes in front and either disk or drum brakes in the rear connected by a system of tubes and hoses that link the brake at each wheel to the master cylinder (Figure).Basically, all car brakes are friction brakes. When the driver applies the brake, the control device forces brake shoes, or pads, against the rotating brake drum or disks at wheel. Friction between the shoes or pads and the drums or disks then slows or stops the wheel so that the car is braked.In most modern brake systems (see Figure 15.1), there is a fluid-filled cylinder, called master cylinder, which contains two separate sections, there is a piston in each section and both pistons are connected to a brake pedal in the driver’s compartment. When the brake is pushed down, brake fluid is sent from the master cylinder to the wheels.At the wheels, the fluid pushes shoes, or pads, against revolving drums or disks. The friction between the stationary shoes, or pads, and the revolving drums or disks slows and stops them. This slows or stops the revolving wheels, which, in turn, slow or stop the car.The brake fluid reservoir is on top of the master cylinder. Most cars today have a transparent r reservoir so that you can see the level without opening the cover. The brake fluid level will drop slightly as the brake pads wear. This is a normal condition and no cause for concern. If the level drops noticeably over ashort period of time or goes down to about two thirds full, have your brakes checked as soon as possible. Keep the reservoir covered except for the amount of time you need to fill it and never leave a cam of brake fluid uncovered. Brake fluid must maintain a very high boiling point. Exposure to air will cause the fluid to absorb moisture which will lower that boiling point.The brake fluid travels from the master cylinder to the wheels through a series of steel tubes and reinforced rubber hoses. Rubber hoses are only used in places that require flexibility, such as at the front wheels, which move up and down as well as steer. The rest of the system uses non-corrosive seamless steel tubing with special fittings at all attachment points. If a steel line requires a repair, the best procedure is to replace the compete line. If this is not practical, a line can be repaired using special splice fittings that are made for brake system repair. You must never use copper tubing to repair a brake system. They are dangerous and illegal.Drum brakes, it consists of the brake drum, an expander, pull back springs, a stationary back plate, two shoes with friction linings, and anchor pins. The stationary back plate is secured to the flange of the axle housing or to the steering knuckle. The brake drum is mounted on the wheel hub. There is a clearance between the inner surface of the drum and the shoe lining. To apply brakes, the driver pushes pedal, the expander expands the shoes and presses them to the drum. Friction between the brake drum and the friction linings brakes the wheels and the vehicle stops. To releasebrakes, the driver release the pedal, the pull back spring retracts the shoes thus permitting free rotation of the wheels.Disk brakes, it has a metal disk instead of a drum. A flat shoe, or disk-brake pad, is located on each side of the disk. The shoes squeeze the rotatin g disk to stop the car. Fluid from the master cylinder forces the pistons to move in, toward the disk. This action pushes the friction pads tightly against the disk. The friction between the shoes and disk slows and stops it. This provides the braking action. Pistons are made of either plastic or metal. There are three general types of disk brakes. They are the floating-caliper type, the fixed-caliper type, and the sliding-caliper type.Floating-caliper and sliding-caliper disk brakes use a single piston. Fixed-caliper disk brakes have either two or four pistons.The brake system assemblies are actuated by mechanical, hydraulic or pneumatic devices. The mechanical leverage is used in the parking brakes fitted in all automobile. When the brake pedal is depressed, the rod pushes the piston of brake master cylinder which presses the fluid. The fluid flows through the pipelines to the power brake unit and then to the wheel cylinder. The fluid pressure expands the cylinder pistons thus pressing the shoes to the drum or disk. If the pedal is released, the piston returns to the initialposition, the pull back springs retract the shoes, the fluid is forced back to the master cylinder and braking ceases.The primary purpose of the parking brake is to hold the vehicle stationary while it is unattended. The parking brake is mechanically operated by the driver when a separate parking braking hand lever is set. The hand brake is normally used when the car has already stopped. A lever is pulled and the rear brakes are approached and locked in the “on” position. The car may now be left without fear of its rolling away. When the driver wants to move the car again, he must press a button before the lever can be released. The hand brake must also be able to stop the car in the event of the foot brake failing. For this reason, it is separate from the foot brake uses cable or rods instead of the hydraulic system.Anti-lock Brake SystemAnti-lock brake systems make braking safer and more convenient, Anti-lock brake systems modulate brake system hydraulic pressure to prevent the brakes from locking and the tires from skidding on slippery pavement or during a panic stop.Anti-lock brake systems have been used on aircraft for years, and some domestic car were offered with an early form of anti-lock braking in late 1990’s. Recently, several automakers have introduced more sophisticated anti-lock system. Investigations in Europe, where anti-lock brakin g systems have been available for a decade, have led one manufacture to state that the number of traffic accidents could be reduced by seven and a half percent if all cars had anti-lock brakes. So some sources predict that all cars will offer anti-lock brakes to improve the safety of the car.Anti-lock systems modulate brake application force several times per second to hold the tires at a controlled amount of slip; all systems accomplish this in basically the same way. One or more speed sensors generate alternating current signal whose frequency increases with the wheel rotational speed. An electronic control unit continuously monitors these signals and if the frequency of a signal drops too rapidly indicating that a wheel is about to lock, the control unit instructs a modulating device to reduce hydraulic pressure to the brake at the affected wheel. When sensor signals indicate the wheel is again rotating normally, the control unit allows increased hydraulic pressure to the brake. This release-apply cycle occurs several time per second to “pump” the brakes like a driver might but at a much faster rate.In addition to their basic operation, anti-lock systems have two other things in common. First, they do not operate until the brakes are applied with enough force to lock or nearly lock a wheel. At all other times, the system stands ready to function but does not interfere with normal braking. Second, if the anti-lock system fail in any way, the brakes continue to operate without anti-lock capability. A warning light on the instrument panel alerts the driver when a problem exists in the anti-lock system.The current Bosch component Anti-lock Braking System (ABSⅡ), is a second generation design wildly used by European automakers such as BWM,Mercedes-Benz and Porsche. ABSⅡsystem consists of : four wheel speed sensor, electronic control unit and modulator assembly.A speed sensor is fitted at each wheel sends signals about wheel rotation to control unit. Each speed sensor consists of a sensor unit and a gear wheel. The front sensor mounts to the steering knuckle and its gear wheel is pressed onto the stub axle that rotates with the wheel. The rear sensor mounts the rear suspension member and its gear wheel is pressed onto the axle. The sensor itself is a winding with a magnetic core. The core creates a magnetic field around the winding, and as the teeth of the gear wheel move through this field, an alternating current is induced in the winding. The control unit monitors the rate o change in this frequency to determine impending brake lockup.The control unit’s function can be divide d into three parts: signal processing, logic and safety circuitry. The signal processing section is the converter that receives the alternating current signals form the speed sensors and converts them into digital form for the logic section. The logic section then analyzes the digitized signals to calculate any brake pressure changes needed. If impending lockup is sensed, the logic section sends commands to the modulator assembly.Modulator assemblyThe hydraulic modulator assembly regulates pressure to the wheel brakes when it receives commands from the control utuit. The modulator assembly can maintain or reduce pressure over the level it receives from the master cylinder, it also can never apply the brakes by itself. The modulator assembly consists of three high-speed electric solenoid valves, two fluid reservoirs and a turn delivery pump equipped with inlet and outlet check valves. The modulator electrical connector and controlling relays are concealed under a plastic cover of the assembly.Each front wheel is served by electric solenoid valve modulated independently by the control unit. The rear brakes are served by a single solenoid valve and modulated together using the select-low principle. During anti-braking system operation, the control unit cycles the solenoid valves to either hold or release pressure the brake lines. When pressure is released from the brake lines during anti-braking operation, it is routed to a fluid reservoir. There is one reservoir for the front brake circuit. The reservoirs are low-pressure accumulators that store fluid under slight spring pressure until the return delivery pump can return the fluid through the brake lines to the master cylinder.汽车制动系统制动系统是汽车中最重要的系统。

附录How Does the Clutch WorkThe clutch is a device to engage and disengage power from the engine, allowing the vehicle to stop and start.A pressure plate or “driving member” is bolted to the engine flywheel, and a clutch plate or “driven member” is loc ated between the flywheel and the pressure plate. The clutch plate is spline to the shaft extending from the transmission to the flywheel, commonly called a clutch shaft or input shaft. When the clutch and pressure plates are locked together by friction, the clutch shaft rotates with the engine crankshaft. Power is transferred from the engine to the transmission, where it is routed through different gear rations to obtain the best speed and power to start and keep the vehicle moving.The flywheel is located at the rear of the engine and is bolted to the crankshaft. It helps absorb power impulses, resulting in a smoothly-idling engine and provides momentum to carry the engine through its operating cycle. The rear surface of the flywheel is machined flat and the clutch components are attached to it. The driving member is commonly called the pressure plate. It is bolted to the engine flywheel and its main purpose is to exert pressure against the clutch plate, holding the plate tight against the flywheel and allowing the power to flow from the engine to the transmission. It must also be capable of interrupting the power flow by releasing the pressure on the clutch plate. This allows the clutch plate to stop rotating while the flywheel and pressure plate continues to rotate.The pressure plate consist of a heavy metal plate, coil springs or diaphragm spring, release levers (fingers), and a cover. When coil springs are used, they are evenly spaced around the metal plate and located between the plate and the metal cover. This places an even pressure against the plate, which in turn presses the clutch plate tight against the flywheel. The cover is bolted tightly to the flywheel and the metal pate is movable, due to internal linkages. The coil springs are arranged to exert direct or indirect tension on the metal plate, depending upon the manufacturer’s design. Three release levers (fingers), evenly spaced around the cover, are used on most pressure plates to release the holding pressure of the springs on the clutch plate, allowing it to disengage the power flow.When a diaphragm spring is used instead of coil springs, the internal linkage is necessarily different to provide an “over-center” action to release the clutch plate from the flywheel. Its operation can be compared to the operation of an oilcan. When depressing the slightly curved metal on the bottom of the oilcan, it goes over-center and gives out a loud “clicking” noise; when released, the noise is again heard as the metal returns to its originalposition. A click is not heard in the clutch operation, but the action of the diaphragm spring is the same as the oilcan.The clutch plate or driven member consists of a round metal plate attached to a splined hub. The outer portion of the round plate is covered with a friction material of molded or woven asbestos and is riveted or bonded to the plate. The thickness of the clutch plate and /or facings may be warped to give a softer clutch engagement. Coil springs are often installed in the hub to help provide a cushion against the twisting force of engagement. The splined hub is mated to (and turns) a splined transmission shaft when the clutch is engaged.The release (throw out) bearing is usually a ball bearing unit, mounted on a sleeve, and attached to the release or throw out lever. Its purpose is to apply pressure to the diaphragm spring or release levers in the pressure plate. When the clutch pedal is depressed, the pressure of the release bearing or lever actuates the internal linkages of the pressure plate, releasing the clutch plate and interrupting the power flow. The release bearing is not in constant contract with the pressure plate. A linkage adjustment clearance should be maintained.The clutch pedal provides mechanical means for the driver to control the engagement and disengagement of the clutch. The pedal is connected mechanically to either a cable or rods, which are directly connected to the release bearing lever.When the clutch pedal is depressed, the linkage moves the release bearing lever. The release lever is attached at the opposite end to a release bearing which straddles the transmission clutch shaft, and presses inward on the pressure plate gingers or the diaphragm spring. This inward pressure acts upon the fingers and internal linkage of the pressure plate and allows the clutch plate to move away from the flywheel, interrupting the flow of power.While the clutch pedal is depressed and the power flow interrupted, the transmission can be shifted in to any gear. The clutch pedal is slowly released to gradually move the clutch pate toward the flywheels under pressure of the pressure plate springs. The friction between the clutch plate and flywheel becomes greater as the pedal is released and the engine speed increased. Once the vehicle is moving, the need for clutch slippage is lessened, and the clutch pedal can be fully released.Coordination between the clutch pedal and accelerator is important to avoid engine stalling, shock to the driveline components and excessive clutch slippage and overheating.离合器如何工作离合器是传递和分离发动机动力的装置，实现车辆的停车和启动。

Automobile Brake System汽车制动系统The braking system is the most important system in cars。

If the brakes fail, the result can be disastrous。

Brakes are actually energy conversion devices, which convert the kinetic energy (momentum）of the vehicle into thermal energy (heat).When stepping on the brakes，the driver commands a stopping force ten times as powerful as the force that puts the car in motion. The braking system can exert thousands of pounds of pressure on each of the four brakes。

Two complete independent braking systems are used on the car. They are the service brake and the parking brake。

The service brake acts to slow，stop，or hold the vehicle during normal driving。

They are foot—operated by the driver depressing and releasing the brake pedal。

The primary purpose of the brake is to hold the vehicle stationary while it is unattended。

Transmission SystemA Basic Parts of the transmission systemThe transmission system applies to the components needed to transfer the drive from the engine to the road wheels. The main components and their purposes are(1) Clutch --- to disengage the drive--- to provide a smooth take-up of the drive(2) Gearbox --- to increase the torque applied to the driving road wheels--- to enable the engine to operate within a given range of speed irrespective of the vehicle speed--- to give reverse motion of the vehicle--- to provide a neutral position so that the engine can run without moving the vehicle(3) Final drive --- to turn the drive through 90°--- to reduce the speed of the drive by a set amount to match the engine to the vehicle(4) Differential --- to allow the inner driving road wheel to rotate slower than theouter wheel when the vehicle is cornering, whilst it ensuresthat a drive is applied equally to both wheels.B Clutch and Clutch ServiceIn order to transmit the power of the engine to the road wheels of a car, a friction clutch and a change-speed gearbox are normally employed. The formeris necessary in order to enable the drive to be taken up gradually and smoothly, while the latter provides different ratios of speed reduction from the engine to the wheels, to suit the particular conditions of running,A clutch performs two tasks:(1) it disengages the engine from the gearbox to allow for gear changing.(2) it is a means for gradually engaging the engine to the driving wheels, when a vehicle is to be moved from rest the clutch must engage a stationary gearbox 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 start (come to test).C Clutch ActionTo start the engine, the driver must depress the clutch pedal. This disengages the gearbox from the engine. To move the car, the driver must reengage the gearbox 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. The load must be applied gradually to operate the car smoothly.A driver depresses the clutch pedal to shift the gears inside the gearbox. After the driver releases the clutch pedal, the clutch must act as solid coupling device. It must transmit all engine power to the gearbox, without slipping.The clutch mechanism include three basic parts: driving member, driven member, operating members.●The driving memberThe 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.●The driven memberThe 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.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.●Operating MembersThese are the parts that release pressure from the clutch disc. The operatingmembers 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.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.At this point, the torque of the engine cannot turn the gearbox input shaft. The gears in the gearbox may be shifted or the vehicle can be brought to a full stop.When the clutch pedal is released, the pressure plate forces the clutch disc against the flywheel. The clutch return spring helps raise the pedal.D Clutch ServiceThe major parts of the clutch assembly need no maintenance or lubrication during normal service. However, all linkage parts need lubrication at points of contact. The linkage itself must be adjusted to prevent wear of the clutch disc.●Free-play AdjustmentYou can make only one adjustment on the clutch linkage —the free-play adjustment. Free play is the allowable space between the throwout bearing and the pressure plate release levers. This space is important because it prevents pressure on the levers that could keep the clutch from engaging fully. In other words, the throwout bearing must be slightly away from the pressure plate leversso that the bearing applies no pressure on the levers. On the other hand, there must not be too much free play between the bearing and the levers. With too much clearance, the clutch cannot fully disengaged when the driver press the clutch pedal to the floor. In most cases, you measure the free play at the clutch pedal, rather than at the bell housing.The free play allows some motion at the beginning of the clutch pedal travel, before the pedal meets resistance. Since the distance varies with the type of pressure plate, check the service manual. Usually, free play should be about 20 to 25mm.Free play can be adjusted at some point where the clutch linkage consists of threaded rods with locknuts. The rod closest to the clutch fork is the most common adjustment point. Begin by locating the rod and locknut beneath the vehicle. Then determine which way to turn the adjustment nuts to get the correct free play at the pedal. You can get a rough estimate of free play by moving the clutch fork to see if it still has some movement. The best way to make the adjustment is to loosen the locknut and move the adjustment nut a few turns. Then check the free play at the pedal. Continue making adjustments until you have the correct free play. When the free-play adjustment meets the manufacturer’s specification, tighten the locknut.Check the free-play adjustment every six months and make any adjustment. Clutches need adjustment that often, since free play decreases slightly as the clutch disc wears. However, the need for frequent adjustments means a problemin the clutch mechanism itself.There must be free play between the throwout bearing and pressure plate release levers. Problems can result from “riding the clutch”. A driver who rests one foot on the clutch pedal causes the throwout bearing to rub against the clutch release levers. As a result, the throwout bearing becomes worn quickly. Also, the clutch disc may wear out due to slippage because the parts are not fully engaged.●Clutch FaultsThe following are the main faults:Slip —failure of the surface to grip resulting in the driven plate revolving slower than the engine flywheel : Clutch gets hot and emits an odor.Spin or drag —failure of the plates to separate resulting in noise from thegearbox when selecting a gear: most noticeable when thevehicle is stationary.Judder —a vibration which occurs when the clutch is being engaged , i.e.when the vehicle is stationary.Fierceness —sudden departure of the vehicle even though the pedal is being released gradually.E The Clutches（supplementary contract）A clutch is a friction device used to connect and disconnect a driving force from a driven member. In automotive applications, it is used in conjunction with an engine flywheel to provide smooth engagement and disengagement of theengine and manual transmission.Since an internal combustion engine develops little power or torque at low rpm, it must gain speed before it will move the vehicle. However, if a rapidly rotating engine is suddenly connected to the drive line of a stationary vehicle, a violent shock will result.So gradual application of load, along with some slowing of engine speed , is needed to provide reasonable and comfortable starts. In vehicles equipped with a manual transmission, this is accomplished by means of a mechanical clutch.The clutch utilizes friction for its operation. The main parts of the clutch are a pressure plate, and a driven disk. The pressure plate is coupled with the flywheel, while the driven disk is fitted to the disk by the springs so that the torque is transmitted owing to friction forces from the engine to the input shaft of the transmission. Smooth engagement is ensured by slipping of the disk before a full pressure is applied.The automobiles are equipped with a dry spring-loaded clutch. The clutch is termed “dry” because the surfaces of the pressure plate and driven disks are dry in contrast to oil-bath clutches in which the plate and disks operate in a bath of oil. It is called “springloaded”because the pressure plate and the driven disk are always pressed to each other by springs and are released only for a time to shift gears or to brake the automobile.In addition to the plate and disk, the clutch includes a cover, release levers, a release yoke, pressure springs and a control linkage. The clutch cover is a steelstamping bolted to the flywheel. The release levers are secured inside the cover on the supporting bolts. The outer ends of the release levers are articulated to the pressure plate. Such a construction allows the pressure plate to approach the cover or move away from it, all the time rotating with the cover or move away from it, all the time rotating with the flywheel. The springs spaced around the circumference between the pressure plate and the clutch cover clamp the driven disk between the pressure plate and the flywheel.The springs are installed with the aid of projections and sockets provided on the cover and pressure plate. The pressure plate sockets have thermal-insulation gaskets for protecting the springs against overheating.The clutch release mechanism can be operated either mechanically or hydraulically. The mechanically-operated release mechanism consists of a pedal, a return spring, a shaft with lever, a rod m release yoke lever, a release yoke, a release ball bearing with support and a clutch release spring. When the clutch pedal is depressed, the rod and shaft with yoke shift the release bearing and support assembly. The release bearing presses the inner ends of the release levers, the pressure plate is moved away from the driven disk and the clutch is disengaged. To engage the clutch , the pedal is released, the release bearing and support assembly is shifted back by the return spring thus releasing the release levers so that the pressure plate is forced by its springs towards the flywheel to clamp the driven disk and engage the clutch.The clutch hydraulically-operated release mechanism consists of a clutchpedal , clutch release spring , a main cylinder , a pneumatic booster, pipelines and hoses and a lever of the clutch release yoke shaft. Time main cylinder accommodates a piston with a cup. The pneumatic booster serves to decrease the pedal force required disengage the clutch. The booster includes two housings with the servo diaphragm clamped in between. The housing accommodates pneumatic, hydraulic and servo plungers. When the clutch pedal is pushed, the fluid pressure from the main cylinder is transmitted through the pipelines and hoses to the hydraulic and servo plungers of the pneumatic booster.The servo arrangement is intended for automatic change of the air pressure in the pneumatic cylinder proportionally to the force applied to the pedal. The plunger moves with the diaphragm, the outlet valve closes and the inlet valve opens thus admitting the compressed air to the pneumatic plunger piston. The forces created by the pneumatic and hydraulic plungers are added together and are applied through the push rod to the release yoke shaft lever; the lever turns the shaft and the release yoke, thus disengaging the clutch. After the clutch pedal is released, the outlet valve opens and the air from the cylinder is let out to the atmosphere.Automatic clutches were used in certain U.S. and European cars. American Motors’“E-Stick”clutch eliminated the need for physical operation of the clutch system called “Hydrak”, which consisted of a fluid flywheel connected to a single, dry disk clutch.In the “E-Stick”set up, the pressure plate levers “engage”the clutch disk rather than “release” them. Also, the clutch remains disengaged until a servo unit is applied by oil pressure when the shift lever is placed “in gear”with the engine running.The “Hydrak” unit also begins operation when the lever is “in gear”. This activates a booster unit, which disengages the clutch disk. The hydraulic clutch parts are bridged over by a free-wheel unit, which goes into action when the speed of the rear wheel is higher than the speed of the engine. A special device controls engagement of the mechanical clutch, depending on whether the rear axle is in traction or is pushed by car momentum.A more-or-les unusual clutch pressure plate set-up is used on late model Chrysler and American Motors cars. Called a semi-centrifugal clutch, the pressure plate has six cylindrical rollers which move outward under centrifugal force until they contact the cover. As engine speed increases, the rollers wedge themselves between the pressure plate and cover so that the faster the clutch rotates, the greater the pressure exerted on the pressure plate and disk.传动系统A基本传动系统的组成部份传动系统是将发动机动力转移到驱动轮的结构。

Transmission SystemA Basic Parts of the transmission systemThe transmission system applies to the components needed to transfer the drive from the engine to the road wheels. The main components and their purposes are (1) Clutch --- to disengage the drive--- to provide a smooth take-up of the drive(2) Gearbox --- to increase the torque applied to the driving road wheels--- to enable the engine to operate within a given range of speed irrespective of the vehicle speed--- to give reverse motion of the vehicle--- to provide a neutral position so that the engine can run without moving the vehicle(3) Final drive --- to turn the drive through 90°--- to reduce the speed of the drive by a set amount to match the engine to the vehicle(4) Differential --- to allow the inner driving road wheel to rotate slower than the outerwheel when the vehicle is cornering, whilst it ensures that adrive is applied equally to both wheels.B Clutch and Clutch ServiceIn order to transmit the power of the engine to the road wheels of a car, a friction clutch and a change-speed gearbox are normally employed. The former is necessary in order to enable the drive to be taken up gradually and smoothly, while the latter provides different ratios of speed reduction from the engine to the wheels, to suit the particular conditions of running,A clutch performs two tasks:(1) it disengages the engine from the gearbox to allow for gear changing.(2) it is a means for gradually engaging the engine to the driving wheels, when a vehicle is to be moved from rest the clutch must engage a stationary gearbox shaftwith 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 start (come to test).C Clutch ActionTo start the engine, the driver must depress the clutch pedal. This disengages the gearbox from the engine. To move the car, the driver must reengage the gearbox 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. The load must be applied gradually to operate the car smoothly.A driver depresses the clutch pedal to shift the gears inside the gearbox. After the driver releases the clutch pedal, the clutch must act as solid coupling device. It must transmit all engine power to the gearbox, without slipping.The clutch mechanism include three basic parts: driving member, driven member, operating members.●The driving memberThe 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.●The driven memberThe 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.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 vibrationsof 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.●Operating MembersThese 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.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.At this point, the torque of the engine cannot turn the gearbox input shaft. The gears in the gearbox may be shifted or the vehicle can be brought to a full stop.When the clutch pedal is released, the pressure plate forces the clutch disc against the flywheel. The clutch return spring helps raise the pedal.D Clutch ServiceThe major parts of the clutch assembly need no maintenance or lubrication during normal service. However, all linkage parts need lubrication at points of contact. The linkage itself must be adjusted to prevent wear of the clutch disc.●Free-play AdjustmentYou can make only one adjustment on the clutch linkage —the free-play adjustment. Free play is the allowable space between the throwout bearing and the pressure plate release levers. This space is important because it prevents pressure on the levers that could keep the clutch from engaging fully. In other words, the throwout bearing must be slightly away from the pressure plate levers so that the bearing applies no pressure on the levers. On the other hand, there must not be too much freeplay between the bearing and the levers. With too much clearance, the clutch cannot fully disengaged when the driver press the clutch pedal to the floor. In most cases, you measure the free play at the clutch pedal, rather than at the bell housing.The free play allows some motion at the beginning of the clutch pedal travel, before the pedal meets resistance. Since the distance varies with the type of pressure plate, check the service manual. Usually, free play should be about 20 to 25mm.Free play can be adjusted at some point where the clutch linkage consists of threaded rods with locknuts. The rod closest to the clutch fork is the most common adjustment point. Begin by locating the rod and locknut beneath the vehicle. Then determine which way to turn the adjustment nuts to get the correct free play at the pedal. You can get a rough estimate of free play by moving the clutch fork to see if it still has some movement. The best way to make the adjustment is to loosen the locknut and move the adjustment nut a few turns. Then check the free play at the pedal. Continue making adjustments until you have the correct free play. When the free-play adjustment meets the manufacturer’s specification, tighten the locknut.Check the free-play adjustment every six months and make any adjustment. Clutches need adjustment that often, since free play decreases slightly as the clutch disc wears. However, the need for frequent adjustments means a problem in the clutch mechanism itself.There must be free play between the throwout bearing and pressure plate release levers. Problems can result from “riding the clutch”. A driver who rests one foot on the clutch pedal causes the throwout bearing to rub against the clutch release levers. As a result, the throwout bearing becomes worn quickly. Also, the clutch disc may wear out due to slippage because the parts are not fully engaged.●Clutch FaultsThe following are the main faults:Slip —failure of the surface to grip resulting in the driven plate revolving slower than the engine flywheel : Clutch gets hot and emits an odor.Spin or drag —failure of the plates to separate resulting in noise from thegearbox when selecting a gear: most noticeable when thevehicle is stationary.Judder —a vibration which occurs when the clutch is being engaged , i.e. when the vehicle is stationary.Fierceness —sudden departure of the vehicle even though the pedal is being released gradually.E The Clutches（supplementary contract）A clutch is a friction device used to connect and disconnect a driving force from a driven member. In automotive applications, it is used in conjunction with an engine flywheel to provide smooth engagement and disengagement of the engine and manual transmission.Since an internal combustion engine develops little power or torque at low rpm, it must gain speed before it will move the vehicle. However, if a rapidly rotating engine is suddenly connected to the drive line of a stationary vehicle, a violent shock will result.So gradual application of load, along with some slowing of engine speed , is needed to provide reasonable and comfortable starts. In vehicles equipped with a manual transmission, this is accomplished by means of a mechanical clutch.The clutch utilizes friction for its operation. The main parts of the clutch are a pressure plate, and a driven disk. The pressure plate is coupled with the flywheel, while the driven disk is fitted to the disk by the springs so that the torque is transmitted owing to friction forces from the engine to the input shaft of the transmission. Smooth engagement is ensured by slipping of the disk before a full pressure is applied.The automobiles are equipped with a dry spring-loaded clutch. The clutch is termed “dry”because the surfaces of the pressure plate and driven disks are dry in contrast to oil-bath clutches in which the plate and disks operate in a bath of oil. It is called “springloaded”because the pressure plate and the driven disk are alwayspressed to each other by springs and are released only for a time to shift gears or to brake the automobile.In addition to the plate and disk, the clutch includes a cover, release levers, a release yoke, pressure springs and a control linkage. The clutch cover is a steel stamping bolted to the flywheel. The release levers are secured inside the cover on the supporting bolts. The outer ends of the release levers are articulated to the pressure plate. Such a construction allows the pressure plate to approach the cover or move away from it, all the time rotating with the cover or move away from it, all the time rotating with the flywheel. The springs spaced around the circumference between the pressure plate and the clutch cover clamp the driven disk between the pressure plate and the flywheel.The springs are installed with the aid of projections and sockets provided on the cover and pressure plate. The pressure plate sockets have thermal-insulation gaskets for protecting the springs against overheating.The clutch release mechanism can be operated either mechanically or hydraulically. The mechanically-operated release mechanism consists of a pedal, a return spring, a shaft with lever, a rod m release yoke lever, a release yoke, a release ball bearing with support and a clutch release spring. When the clutch pedal is depressed, the rod and shaft with yoke shift the release bearing and support assembly. The release bearing presses the inner ends of the release levers, the pressure plate is moved away from the driven disk and the clutch is disengaged. To engage the clutch , the pedal is released, the release bearing and support assembly is shifted back by the return spring thus releasing the release levers so that the pressure plate is forced by its springs towards the flywheel to clamp the driven disk and engage the clutch.The clutch hydraulically-operated release mechanism consists of a clutch pedal , clutch release spring , a main cylinder , a pneumatic booster, pipelines and hoses and a lever of the clutch release yoke shaft. Time main cylinder accommodates a piston with a cup. The pneumatic booster serves to decrease the pedal force required disengage the clutch. The booster includes two housings with the servo diaphragm clamped in。

Clutch Common ProblemsFrom the 1950s to the 1970s, you could count on getting between 50,000 and 70,000 miles from your car's clutch. Clutches can now last for more than 80,000 miles if you use them gently and maintain them well. If not cared for, clutches can start to break down at 35,000 miles. Trucks that are consistently overloaded or that frequently tow heavy loads can also have problems with relatively new clutches.The most common problem with clutches is that the friction material on the disc wears out. The friction material on a clutch disc is very similar to the friction material on the pads of a disc brake or the shoes of a drum brake -- after a while, it wears away. When most or all of the friction material is gone, the clutch will start to slip, and eventually it won't transmit any power from the engine to the wheels.The clutch only wears while the clutch disc and the flywheel are spinning at different speeds. When they are locked together, the friction material is held tightly against the flywheel, and they spin in sync. It's only when the clutch disc is slipping against the flywheel that wearing occurs. So, if you are the type of driver who slips the clutch a lot, you'll wear out your clutch a lot faster.Sometimes the problem is not with slipping, but with sticking. If your clutch won't release properly, it will continue to turn the input shaft. This can cause grinding, or completely prevent your car from going into gear. Some common reasons a clutch may stick are:Broken or stretched clutch cable- The cable needs the right amount of tension to push and pull effectively.Leaky or defective slave and/or master clutch cylinders - Leaks keep the cylinders from building the necessary amount of pressure.Air in the hydraulic line - Air affects the hydraulics by taking up space the fluid needs to build pressure.Misadjusted linkage - When your foot hits the pedal, the linkage transmits the wrong amount of force.Mismatched clutch components- Not all aftermarket parts work with your clutch.A "hard" clutch is also a common problem. All clutches require some amount of force to depress fully. If you have to press hard on the pedal, there may be something wrong. Sticking or binding in the pedal linkage, cable, cross shaft, or pivot ball are common causes. Sometimes a blockage or worn seals in the hydraulic system can also cause a hard clutch.Another problem associated with clutches is a worn throw-out bearing, sometimes called a clutch release bearing. This bearing applies force to the fingers of the spinning pressure plate to release the clutch. If you hear a rumbling sound when the clutch engages, you might have a problem with the throw-out.Clutch Diagnostic TestIf you find that your clutch has failed, here is an at-homediagnostic test that anyone can perform:1. Start your car, set the parking break, and put the carin neutral.2. With your car idling, listen for a growling noisewithout pushing the clutch in. If you hear something,it's most likely a problem with the transmission. If youdon't hear a noise, proceed to step three.3. With the car still in neutral, begin to push the clutchand listen for noise. If you hear a chirping noise asyou press, it's most likely the clutch release, orthrow-out bearing. If you don't hear a noise, proceedto step four.4. Push the clutch all the way to the floor. If you hear asquealing noise, it's probably the pilot bearing orbushing.If you don't hear any noise during these four steps, then yourproblem is probably not the clutch. If you hear the noise atidle and it goes away when the clutch is pressed, it may bean issue in the contact point between the fork and pivot ball.BiomaterialsManufacturers are starting biomaterials to reduce CO2 emissions throughout the vehicles lifecycleManufacturers are starting to concentrate more closely on cutting carbon dioxide emissions from vehicles’ lifecycles. That means looking at the carbon dioxide production and disposal of the vehicle, not just the pollutants that come out of the tailpipe.European vehicle recycling laws are making carmakers that sell cars in Europe take more responsibility for the effect their vehicles Honda and Mitsubishi are the latest to develop new materials.Recycling the metal that makes up majority of the vehicle is not the hardest pert; the plastics plastics present a far greater challenge. Interiors pose a particular recycling problem as they use a lot of plastics.Honda has developed a plant-based fabric with excellent durability and resistance to sunlight for use a surface material in automobile interiors.Bio-fabrics are the most likely solution as they are derived from plants that absorb carbon dioxide ad they grow. When vehicle is scrapped and the fabrics incinerated, only some of the released carbon dioxide has come from a fossil source.Despite this benefit, plant-based fabrics have not yet been used commercially for automobile interiors. Interior quality is too important to take risks with and there have been concerns about the limited durability and aesthetics of biomaterials.Honda says it has a fabric that can overcome these issues, achieving a soft and smooth material appropriate for the surface of automobile interiors. It has high durability and its color does not fade after prolonged exposure to sunlight.Honda will use the material for seats, the interior surface of doors, roof linings and for floor mats. Series production is still some way off , however. The firm will install the bio-fabric interiors in 2009 in a fuel cell vehicle and then expand the application.The bio-fabric’s basic material is a polyester called polypropylene terephthalate (PPT). PPT is produced through the polymerization of propaneiol, which is produced from corn and terephthalic acid, a petroleum-based component.In order to improve the fabric’s stability, Honda has applied a multi-thread structure for the fiber. “The fiber is very flexible, achieving unprecedented aesthetic properties,” says Honda.The bio-fabric does not require changes to existing fabric production processes and is suitable for mass production .Using it instead of the traditional petroleum-based polyester materials reduces the amount of energy consumed in the process by between 10 and 15 percent.“The use of a plant-based ingredient can reduce carbon dioxide emissions by 5Kg per vehicle,” says Honda.Mitsubishi`s environmentally friendly plastic is a little closer to production. It will be used in a concept car next year. But despite its early development stage, the firm is confident it will be used in car interiors.Mitsubishi has developed a material that uses a plant-based resin, polybutylene succinate (PBS), reinforced with bamboo fibers. They began developing the materials with the Aichi industrial technology institute, Japan in 2004.“To help stop global warming and slow the depletion of oil reserves, we plant to substitute plant-based resins and quick-growing plant fibers for materials such as petroleum-based resins and wood hardboards used in car interiors,” says Mitsubishi.PBS. The main component of the material. Is a plant-based resin composedmainly of succinct acid and 1.4-butanediol.The succinct acid for the material comes from the fermentation of sugar extracted from sugarcane or corn?The new material combines bamboo fiber with PBS in order to increase its rigidity.According to tests. The PBS/bamboo-fiber prototype achieves an estimated 50 percent cut in lifecycle CO2 emissions over petroleum-based polypropylene plastic. Volatile organic compound levels are also reduced drastically over processed wood hardboards; roughly 85 per cent in testing.Bamboo grows to its full height in just a few years, compared with the tens of years required for traditional timber. And as such may be called a potentially sustainable resource.”We expect the research to lead to further breakthroughs in the use of bamboo.” says Mitsubishi.离合器常见问题从20世纪50年代至70年代，你可以依靠离合器行驶50000公里到70000公里。

外文翻译UNDERSTAND CLUTCH IS THE FIRST STEP TOREPAIRFor all the cars on the road, we only have two choices. Our own shift or make cars themselves shift, the third foot on duty will let me tell these car belongs to which type.The third foot pedals are the clutch is the first part of the system, we will see a common forms of the clutch. And the fault and repair of various forms.Many mechanic ignore the clutch system, they only observe internal parts of the guest clutch. In any decision I have before, I declare that I said, not a mechanic engineer. There is no computer, this does not mean that the clutch is not high. They are high, but sometimes we as a high-tech mechanic, technology is still we need.Gm has established several different ways of repair clutch system. Early system resemble each other. Pedal and connecting mains mains, one can enter the clutch control lever shell. Mechanical connection is not applicable to a four-wheel drive car. Except in an old car, we find the connection system, so I will no longer discuss connection system.A clutch system has a cable manipulation. This form is more onefold, they mainly used for the old car. But they were widely used, so I'm going to talk about.One of these early cable system was installed in Chevette Chevrolet obstfeld and Pontiac T - 1000. At the end of the role in the cable is a string. A conditioning nut on the string used to start regulator.Cable and the bearing is whirly fork out for it, and we have seen seem instead, but in the clutch is bearing outer shell, rather than on the inside.Stupid big double regulator not that used to other motors, but due to the front wheel drive, cable system seems to become the hottest system, the automatic clutchregulator is now.A plastic gear system was applied in turn pole mechanical assembly, when the clutch plate, adjust and cable disappear stop. Plastic turned pole is an elastic one-way gear assembly. When the clutch is loose, spring will pull re-rotating cable. When the clutch assembly is completely wear, cables will be spring up to a one-way gear to the next.When the clutch cable is worn or adjusting spring loose and free adjustment is useless. If you want to adjust again with toes [the clutch. Such regulator will be back to normal, when the clutch is pressed, it will decline, or is not working, or sometimes rapid updates. Due to the rapid rotation, heat release, in the most rapid, it will be very annoying, is very dangerous.Fortunately, the regulator seldom fully failure, whether regulator is wrong, will make it back for example.Instead, including allowing smooth momentum from the foot pedals on reserve pin. Then lift the regulator, the brake pedal separate clutch cable ends. When moving the regulator, must pay attention to help, but the problem still exists, and maintenance will appear again soon, the first to relocate cable, then eliminate trouble.In order to eliminate mechanical connection and cable, general adopted the next logical stage started using hydraulic clutch controller in every car and vans.Hydraulic clutch is not a new invention, in my memory, they have been used for many years, but never striking. Mechanical system is cheap, simple.When our car is becoming more and more fuel efficient, save a space, the heavy mechanical system soon lost market. Liquid so adjust parts.The regulator may QiLingBaSui old and new regulators need to recover. It reminds you of puzzle game. When your reshipment new regulator to ensure you the clutch pedal in the correct position. Otherwise, we will release regulator claw or completely to lift the clutch pedal and right foot.Whatever adjustment, clutch cable occasionally wear. Sometimes, cable will wear off in a terminal or. Sometimes the cable in clutch shell internal grinding bad or in the middle. Produce higher results and wear. These wear side may become veryserious obstacle to clutch bearings, clutch skid or loose rapid wear.Don't try to lubricate cable, solid lubricant can press, than to be more useful clutch motor and transmission of the person concerned. The water hydraulic hoses even clutch foot pedals. It can be around or through many mechanical systems to reach.Hydraulic brake system operating as brake system, the clutch pedal to push a foot pole into total control of cylinder. Total control of cylinder is a single piston shape and with a room, a drain hole, you may also require a more simple total control of the cylinder.The liquid through a high-pressure water hose pressure rather than the delivery of brake, it is then pressed into liquid water reservoir.Water is a single reservoir, the piston cylinder reminds you of a single wheel cylinder was blocked. Under pressure. The piston driven force, then reverse clutch bearings manipulation.Because water reservoir with hydraulic operation. Stop hydraulic form, no special requirements of regulating the normal durability. Liquid water is stored in only reservoir and returns control cylinder. When the clutch is worn or self adjusting, this may be the first big re-rotating the state, if the total middle finger cylinder storage pools is lower, total control cylinder will wear or will have liquid leakage, however, a complete tank is not necessarily mean cylinder wear, someone may have to fill the tank.Although hydraulic clutch not solve many problems, it also general invented a new problem. With these problems, the experimental determination and simplify the symptoms.Whenever you doubt hydraulic sliding, don't blame hydraulic system, if the control, hydraulic cylinder failure may is the culprit. These may be caused by leakage control of the cylinder or wear, or store water delivery.Hydraulic problems likely also by system obstacles, internal leakage and hydraulic port expansion of sealing device for hydraulic line is the obstacles or expansion of the sealing cylinder often means someone or use the wrong sort of liquidor use the sewage system, all in the hydraulic device to relocate.Don't managed to replace hydraulic system is only part of the pollution caused by pollution, these seemingly no problems of partial damage. In addition, reserve the pollution will damage the new parts, dredge cylinder brake system and standard of persuation different, you can just make crural footplate know it become stable, then open a roof caving screws, clutch will move and hinder pumping systems.Exhaust pressure type often is your best bet, but for on-off liquid tank connectors.it can find a more durable, vacuum pump is a very good alternant, four in any circumstances to ensure a level, if the vehicle and tilt, air can be sealed.Sometimes, no effective exhaust device or vacuum pumping equipment, or you can expedite system, the first attempt, open storage cylinder gravity exhaust flow, liquid through a system.When gravity method, using a device failure for promoting leave foot pedals, attention, what I say is, not pull open channel according to pedal, swing, when it stops flowing liquid, raise the clutch pedal, foot as a few seconds, can repeat times a second, the maximum operating.When the pedals beating period, if you did not wait long enough, the reservoir will play without water back pure air, every time, waiting to be filled with liquid water reservoir. When shaking pedal, according to air and liquid flows from persuation device.A system is that there will be a general dredge the booster shook push rod, observe the pedal, most of the moving water moving range is general cylinder to also don't believe 0.4 feet a worn hose.The new general work with a plastic, cylinder attached to the belt with a rod and piston cylinder, general all the belt is adjusted. They are trying to prevent is outspread, steady heavy cylinders when pole. When the cylinder is filled up will be broken when belt, you need not worry, they will make your job easier.Greg Boyd where the clutch on recommended in the cylinder, replace rubber hoses, work, you can't afraid of pay V AT and not to do, this is a good method, you can make sure your work will be very smooth without 0.75 'to once every car manual, you will be easier to work.A cylinder is stretched, but about a minute hold cylinder, look to whether store water in situ, if water storage keep in storage, returning to total control of water or will be revealed. CylinderIf not mobile means system of air, water reservoirs have an internal leakage or liquids in total control of the error and not enough or the cylinder block mat in the clutch pedal bound feet into a ball.No sufficient flow can also cause because total control of cylinder bending installation. When installing bending, crural footplate cannot give total control of cylinder provide enough displacement.General work really requires some special attention to cylinder. If you want to use work, don't let it hanging in liquid hose, and gravity will play his forces, the work, sometimes filled cylinders liquid that can, but the expansion of liquid cylinders can cause leakage.If work started out, reinstall the cylinder, it has no choice but to reinstall the pistons, don't MiJian, where, hope things will seal. In most cases it will be temporary reserves, then leak, the liquid will stop working.When you move to work on the cylinder block, however, some material winding, to ensure the cylinder cylinder before moving on to install material, if still in this band, cylinders, will not normal, operation will fail.In order not to damage the water hose, somewhere, hanging cylinder, the weight of the cylinder destruction water hose, but will make other parts, hose at work easily damaged.When you work, you must make sure that, even if not personally inspected hose, by luck, when you are working with some problems in it will be very good reason.Some general work not adjust lever, launched cylinder brake hydraulic device if the normal work, but also does not work, clutch must adjust lever to complement, in length, ensure the normal wear and mechanical clutch brake mechanical components or damage of bearing or bearing fork may cause the same question, then, adjust lever is no use.In fact, if you adjust lever, will produce more questions, stem and cylinder pistoncylinder to the lowest and cylinder effective work, now in the clutch may move abnormal operation, most of the time, the stem is installed beforehand, you can make it to operate, when all methods fail, you again.When we examined the clutch system, there are a few things we note that these are the truth, general any clutch is not exceptional also, maintenance tasks is the key to determine its clutch failed. Then again, avoid apart from the normal durability need to consider we still need to consider some of the many things, so there is no fixed programs.The flywheel: like a fade spots will appear in the surface of the flywheel. Also may see small cracks. These are due to high rotation of clutch. Heat is caused due to excessive sliding, very is due to the failure of the discomfort, spiral spring or drive, the normal damage can also cause slightly curved surfaces.Disc connection between also can make the flywheel bending. Usually results in any worse, under such circumstances, the flywheel are to replace the change.Needle bearing: this is one of the most neglected guy, a weak or inappropriate bearing will cause rapid disc wear. With the input shaft transmission is the damage and bearing. A tight clutch bearings as not all work in the same. Needle bearing is sometimes the ball bearings, closed or a curved bearings, additional oil lubricant or blocked off, and metal holes caused bearing is tight.Seal: any scrolling operation system or motor oil will eventually reach the clutch parts, although the old caused clutch sliding of the clutch is not oil pollution, but also to reposition the seal to prevent contamination of the other components.Intermediate bearing: also called bearings, the bearing is a lot of pressure, whenever the clutch to install, it also according to the standard procedure reinstall the bearings, damage when used a buzzing noise. When the clutch pressure or loosen, noise can change, bearing in spline skidding, clutch, also won't work can produce a smooth imbalance in the load pressure plate, plate, the damage of the damaged parts must also replace.Separate gearshift forks and bearings cabinet: wear and bending fork, cabinet will produce unbalanced load pressure in bearings and pressure plate, unbalanced loadbearing and pressure will cause damage, must fork, then gently lubricating oil, give point, not excessive oil, pollution clutch.Install benchmark: engine, gearbox shell and clutch must be installed in the same baseline, bending and will not start from the center of the lateral loads cause pressure, the pressure will completely destroy all the clutch parts, may damage the engine and transmission.Other damage may be related to the users, however, before the clutch disc armoured off some cracks in the job will cause to split the clutch.You should know that there are some very special universal clutch in general, these problems can be found in the newspaper, although no new component installation or are some outdated components installed, still remember these problems, because it could apply to other vehicles, these problems relating to vehicle can know more than we.1984-1988, with V - 6 Camarosard motors and Firebirds: repeat or premature damage may be due to the fork block loose, make sure it was tight straight.1988Camarosard and FirebirdsV - 6 engine: work is leaking from loosening cylinder, bent nails caused split-finger pitches. Also check the damage of bearing, retained in the fork boomerang. Work cylinder unbalanced loads cause leakage.V - 6, rear wheel drive motor start-up or closed clutch noise, presentation, for the clutch parts damaged clutch motor and the damage is due in a clutch transmission line, from the engine into the stretch of less than 8.8 mm. Now, more can also on the general parts shop to buy.1988Trucks C1500.2 MPV. 2-1 / WD, ton 4.3 V - 6 closed and yoke pivot design limit will cause the yoke will be tied to the tongue clutch bearings. 11-9-87 after a new design of the vehicle, bearings, it long 0.37 inches, general component, 2071736 Numbers.The basic clutch has transform for several years, but the main material, the controller has changed, there are some common sense will go to the maintenance of high-tech clutch.理解离合器的操作是维修的第一步对于路上行驶的所有汽车,我们只有两种选择。

附录The Spin Tester for the Automobile Clutch Test with High Speed Photography SystemAbstract:The development of a new type spin tester for the automobile clutch test is introduced.A vertical flexible shaft system with rubber damper is applied to the tester.The crushing test of the clutch assembly can be done frequently on the spin tester,and the high speed photography system adopting ordinary camera can record the crushing wink.The crushing test of a clutch on this tester is also introduced.and the weak link of the clutch assembly can be found from the photograph of crushing wink.Key words:spin tester automobile clutch high speed photographyClutch by gland assembly and platen assembly which, in their rotation strength is the key parts of the quality evaluation car is an important index, rules and regulations should be acceleration in their state of the rotating speed is higher than speeding strength test to determine the safety and reliability of the clutch disc. For example, santana clutch disc assembly and driven plate total chengdu in ordinary temperature requirements in a = rad/s2 acceleration of 50 acc to 12 000 r/min, and platen assembly also requires in high temperature (250 ℃) at a = rad/s2 acceleration of 50 acc to 10 000 r/min without fracture. These tests require in the specialized testing machine.At present, the domestic is no clutch assembly strength test on the special equipment. This paper introduces the author developed a vertical multi-function of clutch rotating strength tester (see chart 1). It has a strong drive ability (1), can generate enough acceleration, the maximum weight 50 kg, with the highest speed 18 000 r/min, maximum acceleration 20 rad PI/s2 the clutch assembly strength test; (2) the strong vibration absorber system, to absorb the clutch assembly high speed rotating vibration energy; (3) the reliable and steady automation control system and absolute safety of lead brick protection recessed; (4) to observe the clutch assembly rotation experiment process and the rupture instantaneous state surveillance and high-speed photography system. To all sorts of clutch assembly, the machine can strength test, especially for high speed can be frequently do destructive testing, use convenient, safe and reliable.Figure 1 clutch rotating strength tester photos1.The main structure characteristics1.1 With rubber damping bearing on the "flexible shaft typeThis kind of test enginery due to frequent, high-speed destructive testing, the host axis should be able to complete the clutch assembly rose quickly to the whole process of destruction, so we used on the vertical "with rubber damper flexible shaft of [1], the structure see FIG. 2). Due to the vertical axis, one soft critical speed is low, order only 1800 to 2000 r/min or so, make whole high-speed area are on supercritical of smooth state. At the same time in soft shaft with a middle with "O" type of rubber ring damping bearing shaft system, when the critical speed or because the clutch assembly brought serious imbalance fierce, the vibration damping bearing can absorb vibration energy, attenuation shaft vibration [2], ensure the clutch assembly continue to rise until the complete destruction, ensure speed high-speed damage test. This structure is simple, easy to adjust, damping range. In order to prevent the clutch assembly damage time, great instantaneous vibration energy cause shaft and the lower the destruction of the transmission system, in the gentle shaft with a limit bearing, head to prevent soft shaft bending big and the bottom of the drive shaft damage components. Soft axis adopt plug-in installation, when the clutch assembly, the most serious destruction is replaced the soft shaft, head bent to the whole machine didn't have any effect, operation loading and unloading is very convenient, and ensure the tester can frequently in the clutch assembly destructive test. The vertical axis, facilitate "on the cover from the Windows of the testing process and observe specimens of installation and removal.Figure 2 rubber damper with flexible shaft1.2 The clutch assembly damage moments of high-speed photography systemThe clutch assembly by many parts assembly and become, the parts quality is directly related to the quality of the assembly. If can through the high-speed strength test find assembly parts the weak links, had better be to be in test chamber to take the parts assembly by deformation and destruction and yield spread to the whole process of, that will be very significant. Although currently not at a close range in advance, do not know when the clutch assembly of the damage happened produced high speed the whole process of destruction, but they can take to destroy the moment alone photos.Foreign is widely accepted in the specimen outside trigger coil rotor set, as the rotor fly crack, debris flying out of line, met trigger trigger circuit triggered by high speed camera shutter open, took a damage the image of the rotor moment. Obviously this design requirements must have taken the camera very high speed. For example the clutch assembly destruction speed than 10 000 r/min, the linear velocity in the 200 m/s above, if want to take clear debris flying out of the instantaneous movement condition when, captured fragments of the distance from the 2 mm moving images. So, the camera at least should have t = 2 mm / (200 m/s) = 1 x 10-5 s shooting speed, for ordinary camera it is clearly the deficits.In order to solve this problem, we developed a common cameras with the high-speed photography in the technology, with the clutch high-speed strength test machine, took the clutch assembly destruction of photographs. The moment The high-speed photography work principle of the system is shown in figure 3. The specific practices for ordinary camera, will cover the Windows in testing machine in the darkness of the test chamber outside, open shutter, in advance for shooting state. At the same time, add the rear cover outside the window between the two steel ballmust high pressure of the capacitor voltage. When the clutch assembly, high speed rotating parts fly crack damage, cut off the assembly line, the periphery of the trigger that set up light source line work trigger pin, triggering a trigger pulse, so that the air between two steel ball, a steel ball capacitor in ionization produced strong, between discharge pulse light source, then the camera narrow photographic plate, get the clutch assembly destruction of photographs. The moment The technology of the method is simple, save expensive high-speed cameras, the shooting accuracy is high.Figure 3 high-speed photography system work principle diagram2.Experimental studyWe in the testing machine to clutch cover plate assembly and made a large destructive testing. Now to the santana gland assembly damage test as an example. First, take the santana clutch cover assembly state of rest; Then, the gland assembly, and to destroy the damage process using high-speed photography system to shoot, have the following results:(1) santana clutch cover assembly in speed for 11 560 r/min, gland spring of fly out, cut off the trigger coil, took a high-speed photography photos (see chart 4), photos are the right off about 20 ° position on a spring of the flying out of the shadows. After parking the tray found not damage, but find spring of crack, the obvious skeleton spring of centrifugal force along the role in the first bending fly out broken.(2) this gland assembly continue to rise in speed for speed test, 14 010 r/min happened when the tray destruction, like on high-speed photography photos (see chart 5). Photos of the moment by damage, the whole clutch cover visible assembly gland produces serious warping deformation, radial on turn over the close (see photo) and cut off the trigger coil. As gland warping, clutch the tray imbalances fly crack damage. But did not see the gland cast iron rings (cover parts can't photographed) fly out of the shadow of the fracture.(3) from gland assembly destroyed the crack of photos skeleton (see figure 6) cansee, gland serious warping deformation in spring of installation, the gaps, but pulled gland and without breaking into several pieces, although gland lower part of the cast iron ring has fractured into seven pieces, but found no gland inside surface, cast iron rings pieces the trace of the impact.The result shows the santana car clutch cover the failure process of the instantaneous assembly for local parts, (spring of) fly out-gland serious warping deformation, in local weak section and pulled in the bottom of the gland cast iron rings and the whole gland assembly fracture failure.This tester has been put into use of factory three years, because the function is all ready, performance stability, price cheap, and solve the clutch a lot of detection, the development, and the research question, is expected to replace the imported, application.Figure 4 gland assembly spring of fly out of the moment photosFigure 5 gland assembly moments of photos. DamageFigure 6 gland assembly after damage remains of the photoReference[1] WuDaWen. "O" type rubber ring experimental study of the dynamic characteristics of the master's degree thesis: [Master's degree thesis]. Hangzhou, zhejiang university, 1998[2] QianLiXin. Ultra-high speed rotor test development speeding some issues of the study: [Ph.D. Thesis]. Hangzhou, zhejiang university, 1998带高速摄影系统的汽车离合器旋转破坏强度试验机摘要：提供了一种带高速摄影系统的汽车离合器旋转破坏强度试验机，该机可以频繁地做离合器总成的破坏性试验，并可拍摄到离合器总成破坏瞬间的独幅照片，以利找出总成零件的薄弱环节。