Abstract: A hydraulic clutch actuation system having a hydraulic clutch control device which includes at least one clutch master cylinder that communicates via a pressure-medium line with a clutch slave cylinder used for actuating a clutch device, the pressure prevailing in the pressure-medium line being relievable via at least one emergency release valve device to permit disengagement of the clutch device in an emergency situation. The hydraulic clutch actuation system is distinguished in that the emergency release valve device has a seal-carrier device for a sealing element which is movable in response to an electromagnet out of an open position, in which a pressure-medium inlet is open, into a closed position in which the sealing element seals the pressure-medium inlet.

Abstract: A hydraulic clutch actuation system is provided having a hydraulic clutch control device which includes one first clutch master cylinder that communicates via a first pressure-medium line with a first clutch slave cylinder, which is used for actuating a first clutch device, and a second clutch master cylinder that communicates via a second pressure-medium line with a second clutch slave cylinder used for actuating a second clutch device, the pressure prevailing in the first and/or in the second pressure-medium line being relievable via at least one emergency release valve device to permit disengagement of at least one of the clutch devices in an emergency situation.

Abstract: A gearbox actuator comprising a selector shaft 2 which is arranged in a housing and is driven by a drive. A shift finger 3 and disengaging shaped elements 4 used to actuate gearshift rails are arranged on the selector shaft, and jibs for 12-15 supporting and guiding the gearshift rails are arranged on the housing. The gearbox actuator 1 comprises the central selector shaft 2 mounted in bearing elements 19 and comprises a shift finger 3 and two disengaging shaped elements 4 arranged in the center thereof, at a distance corresponding to the width of a channel. Preferably, the selector shaft 2 is driven by a brushless motor 5 by means of a double planetary stage 6 and a toothed segment 7 which engages a toothed wheel 16 that is preferably positioned in a housing element 17. A preferably second brushless motor 8 drives a sliding element 37 by means of spindle 9, the sliding element displacing the shift finger 3 and the disengaging shaped elements 4 on the selector shaft 2.