Abstract: A clutch device for a vehicle, including a spring device (4), which attempts to force a friction plate (3) in a first direction for engagement of the clutch, a pneumatic actuator (10) with a cylinder (11) and a piston (16), which divides the cylinder (11) into a main chamber (20) and an auxiliary chamber (21), and a compressed air source (31), which is arranged via a controllable valve device (32,33) for communication with the main chamber (20) for movement of the friction plate (3) in a second, opposite direction for disengagement of the clutch. The clutch device includes a computer (50) with a memory (54), wherein there is stored a desired auxiliary force exerted against the release bearing (19) as a second function (C2) of the release bearing's (19) position. The clutch device further includes a sensor (22), which is arranged to establish the release bearing's position, and a sensor (23), which is arranged to establish the pressure of the air in the auxiliary chamber.

Abstract: A clutch device for a vehicle, comprising a spring device (4), which attempts to force a friction plate (3) in a first direction for engagement of the clutch, a pneumatic actuator (10) with a cylinder (11) and a piston (16), which divides the cylinder (11) into a main chamber (20) and an auxiliary chamber (21), and a compressed air source (31), which is arranged via a controllable valve device (32,33) for communication with the main chamber (20) for movement of the friction plate (3) in a second, opposite direction for disengagement of the clutch.