Basic Clutch Parts

     Fig. 9.3 shows the major parts of an automotive clutch：

    Clutch release mechanism - allows the driver to disengage the clutch with a footpedal. Generally, it consists of the clutch pedal assembly, either mechanicallinkage, a cable，or a hydraulic circuit，and the clutch fork. Many manufacturersinclude the throw-out bearing as part of the clutch release mechanism

    Clutch disc - also called friction disc，consists of a splined hub and a round metalplate covered with friction material. The splines in the center of the clutch discmesh with splines on the transmission input shaft. This makes the input shaft anddisc turn together. This disc is free to slide back and forth on the shaft

    Pressure plate - a spring-loaded device that can either lock or unlock the clutchdisc and flywheel. It bolts to the flywheel.  The clutch disc fits between theflywheel and pressure plate. There are two basic types of pressure plates：coilspring and diaphragm spring

    Release bearing - also called throw-out bearing, is usually a ball bearing andcollar assembly that reduces friction between the pressure plate levers and theclutch fork. The release bearing is a sealed unit packed with grease

    Clutch fork - also called clutch arm, throw-out lever，or release arm，transfersmotion from  the clutch release mechanism to  the throw-out  bearing andpressure plate

    Clutch housing - also called bell housing, bolts to the rear of the engine,enclosing the clutch assembly. It can be made of aluminum，magnesium, orcast iron