Abstract: A hydraulic actuating device (10) for an automotive friction clutch (12), has a master cylinder (14) whose master piston (16) can be impinged upon with a master force (FG) via an actuating mechanism (18) and can be displaced by a master travel (SG), and a slave cylinder (20) with a slave piston (22) which is hydraulically connected in series to the master piston via a liquid column and is functionally linked with a clutch-release member (24) of the automotive friction clutch. The actuating device may be provided with an adjusting unit (26) may have an adjusting piston (28). The adjusting piston is hydraulically connected in series to the master piston and can be impinged upon with a force and displaced via a transmission (30) that is driven by an electric motor. The actuating device further has a control unit (C) which is used to control the adjusting unit especially subject to a master variable (FG; SG).

Abstract: A hydraulic actuating device (10) for an automotive friction clutch (12), has a master cylinder (14) whose master piston (16) can be impinged upon with a master force (FG) via an actuating mechanism (18) and can be displaced by a master travel (SG), and a slave cylinder (20) with a slave piston (22) which is hydraulically connected in series to the master piston via a liquid column and is functionally linked with a clutch-release member (24) of the automotive friction clutch. The actuating device may be provided with an adjusting unit (26) may have an adjusting piston (28). The adjusting piston is hydraulically connected in series to the master piston and can be impinged upon with a force and displaced via a transmission (30) that is driven by an electric motor. The actuating device further has a control unit (C) which is used to control the adjusting unit especially subject to a master variable (FG; SG).

Abstract: An assembly of a master brake cylinder and an associated power cylinder of larger diameter, disposed in front of the dashboard, is held together under tension by a stirrup-shaped retainer with a bight embracing the free end of the master cylinder and two legs anchored to the dashboard, these legs traversing the power cylinder. A roll membrane inside the power cylinder, forming a flexible partition that divides its interior into two chambers between which a pressure difference is developed to operate the master cylinder, has cuffs attached to two guide tubes rigid with at least one wall of the power cylinder, these tubes being traversed by the retainer legs.