engagement point or kiss point is set which corresponds to a value of the piston travel z k at which the friction clutch 16 can transmit a very low torque in the unpressurized state of the actuator 26 the friction clutch 16 is fully open the travel from the fully open position of the friction clutch to the engagement point is referred to as u201c charging u201d the friction clutch 16 the regulation of the transmission of the torque by the friction clutch 16 takes place above the engagement point wherein in said state the movement of the piston 28 counteracts not only the force of the restoring spring 30 but rather also the internal pressure force of the friction clutch 16 fig2 illustrates a first embodiment of a fluid source 22 the fluid source 22 of fig2 has a pump 34 which is driven by an electric motor and which sucks hydraulic fluid from a tank and delivers a volume flow q pump the electric motor which drives the pump 34 is driven by means of an electrical current i p the rotational speed of the electric motor is denoted by u03c9 p x 1 to improve regulability after the engagement point kiss point is reached a part of the volume flow q pump delivered by the pump 34 is discharged via a throttle 36.