The clutch pressure plate consists of clutch lid, diaphragm spring and pressure ring. It should provide for the necessary pressure force. Moreover, it transfers the torque from the flywheel to the pressure ring.
In contrast to the coil spring clutch (see picture) the actuating force does not rise further with the diaphragm spring clutch (see figure on top) if the pressure point is crossed. It may even decrease. The clutch pedal is always floored completely. Thus a high strain of the gearbox synchronisation is avoided. Moreover, the diaphragm spring is made up easier and lighter because levers are no longer necessary for the transmission of the torque to the pressure ring. Small tangential springs between lid and pressure ring take over this task.
In case the clutch has to undergo repair, besides the clutch disc also the release lever and the clutch pressure plate should be exchanged. 05/08