Abstract:
The friction clutch between the engine and an automated transmission in the power train of a motor vehicle are operated and controlled by an actuator which effects changes in the extent of engagement of the clutch as well as the selection of and shifting into particular gears. The actuator forms part of a unit which receives a pressurized hydraulic fluid from a source including an accumulator and a proportional valve which latter selects the fluid pressure necessary to shift the transmission into a selected gear.