Abstract: A clutch unit comprises a wet friction clutch for controllable transmission of a torque from an input element to an output element, oil for cooling the friction clutch, and an actuator for actuating the friction clutch. In order to control the clutch unit, a temperature is ascertained in the friction clutch. A characteristic curve of the friction clutch that describes the dependence of a clutch torque on an actuator control variable is adapted as a function of the ascertained temperature. The clutch unit is controlled in accordance with the characteristic curve by means of the actuator.

Abstract: The invention relates to a friction clutch having a single-acting actuator which is a piston-cylinder unit and is connected in a controllable fashion to a pressurized fluid source. In order to be able to carry out a fast pilot stroke up to the point at which the clutch makes contact, the piston-cylinder unit has a stepped piston whose first step of small diameter delimits, by means of its cylinder, a first pressure space, and whose second step of relatively large diameter delimits, by means of its cylinder, a second pressure space, a pressure line being connected to the first pressure space and, by means of a first non-return valve which opens at a certain pressure, to the second pressure space, and it also being possible for the second pressure space to be connected via a discharge line and a suction line, which contains a second non-return valve, to the fluid reservoir. The invention also relates to a drive device having clutches of said type.