Device for hydraulically actuating a motor vehicle friction clutch

A device for hydraulic actuation of a motor vehicle friction clutch, comprising a manually actuatable master cylinder, the actuation of which is sensed by a sensor and which has a master pressure chamber which in a rest setting is in fluid connection with a reservoir by way of a replenishing region, a slave arrangement, which has a slave pressure chamber and which comprises at least one slave cylinder operatively connected with the motor vehicle friction clutch, a pressure line for hydraulic connection of the master pressure chamber with the slave pressure chamber, a motor pump, which is hydraulically connected at the inlet side with the reservoir and the pump outlet of which is hydraulically connectible with the pressure line, an electrically actuable valve arrangement connected into the pressure line, and a control unit, with which the sensor, the motor pump and the valve arrangement are electrically connected for manual and/or automatic actuation of the motor vehicle friction clutch, the electrically actuable valve arrangement comprises in parallel connection an electrically actuable proportional valve and a first non-return valve blocking in the direction of the master pressure chamber, wherein the electrically actuable proportional valve and the first non-return valve are arranged in parallel between the motor pump and the actuatable master cylinder, the motor pump being hydraulically connected with the pressure line by way of a second non-return valve, which blocks in the direction of the motor pump, between the valve arrangement and the slave pressure chamber.