The clutch is mounted between the engine and the transmission and is an assembly of the motor drive train directly associated with the engine. Usually the clutch is mounted on the crankshaft of the engine crankshaft and is the part of the engine that is cut and transmitted between the motor and the drive train. During the entire journey from start to normal, the driver can manipulate the clutch as needed to temporarily separate or gradually engage the engine and driveline to cut off or transmit the power output from the engine to the driveline. It is the role of the engine and the transmission can be gradually between the joint, so as to ensure a smooth start of the car; temporarily cut off the connection between the engine and the transmission in order to facilitate the shift and reduce the impact of the shift; when the car emergency braking Separation, to prevent the transmission and other transmission system overload, which play a protective role.
The clutch is similar to the switch, engaged or disengaged from the power transmission, the clutch mechanism of its active part and the driven part can be temporarily separated, but also gradually joined, and in the transmission process also may be relative to the rotation. There is no rigid connection between the actuator and the follower of the clutch. Any form of car has a clutch device, but the form is different.