Self-Adjusting Clutch (SAC)
A self-adjusting clutch (SAC) eliminates problems both in terms of wear in the clutch cover and the need for increased force at the pedal as the facing thickness reduces.
This considerably increases the life of the clutch. A self adjusting clutch will not normally require replacement during the lifetime of the vehicle.
A self-adjusting clutch (SAC) senses the increase in release load at the diaphragm spring. It has a adjustment mechanism between the diaphragm spring and the clutch housing. This maintains the position of the diaphragm spring and ensures that the pedal effort required remains constant throughout the service life of the vehicle.
The pressure plate is of the diaphragm spring type. Unlike a traditional type, the pressure plate contains an adjustment ring made of steel or plastic. If there is wear, the adjustment ring moves slightly to maintain the engagement position of the clutch.
The fact that the fingers are unable to move backwards has the following advantages:
- increased wear capacity
- the clutch cover can be made shorter because space is not required for rearward movement of the diaphragm spring.