Clutch is an important part of automobiles. Clutch is also used widely in heavy industrial machines. Clutch is a mechanical device, which is used to connect or disconnect the source of power or motion either manually or automatically. An automotive clutch when disconnected (neutral) can permit the engine to run without moving a car. This is desirable when the engine is to be started or stopped or when the gears have to be shifted. Similarly when a motor of a heavy textile machine is to be started, the drive to the machine should be disconnected till the motor attains the full or safe-speed. This safeguards the motor; otherwise the motor draws more current to move the static elements of machine, in doing so the coils of motor may burn out. Based on the type of contact between the elements of clutch, clutches are classified as