Patent ID: 7100757
Filing Date: 2006-09-05
Classification: B60W,F16D

Abstract:
1. A clutch device for a vehicle, comprising a mechanical spring device, which constantly attempts to force a friction plate in a first direction for engagement of the clutch and transmission of a torque thereby, a pneumatic actuator which has a cylinder and a piston, which is movable therein, and which divides the cylinder into a main chamber and an auxiliary chamber, a release bearing with a rotating part, which is connected to the spring device and a rotationally stationary part, which is connected to the piston, a compressed air source, which is arranged via a controllable valve device for communication with the main chamber for movement of the friction plate in a second, opposite direction for disengagement of the clutch, a computer with a memory, in which there is stored a desired pressure for the air in the auxiliary chamber and thereby a desired auxiliary force exerted against the release bearing as a second function of the release bearing's position, a first sensor, which is arranged to establish the release bearing's position, a second sensor, which is arranged to establish the pressure of the air in the auxiliary chamber, and a valve device arranged to provide communication between the compressed air source and the auxiliary chamber, the computer being arranged to receive signals from the first and second sensors, establish any difference between the measured auxiliary chamber pressure and the desired auxiliary chamber pressure and to control the controllable valve device and the valve device in accordance with the difference and thereby provide the auxiliary force.