| 摘要 |
A braking pressure generator consists of a hydraulic brake booster (2) actuatable by a brake pedal (16) and of a master brake cylinder (1) whose master cylinder piston (19) is actuatable by a booster piston (14) pressurizable with an auxiliary hydraulic pressure. The booster piston (14) is guided sealedly and axially displaceably in the bore of an annular secondary cylinder piston (41) which, with a front face (52), confines the booster chamber (13) and which, with its stepped surface area (51), confines a secondary cylinder chamber (44) communicating with a pressure chamber (22) of the master brake cylinder (1) via a pressure line (46). In the brake actuating direction, the secondary cylinder piston (41) is supported at a stop ring (48) of a connecting rod (20) between the booster piston (14) and the master cylinder piston (19). In case of an auxilary-pressure-assisted brake application the secondary cylinder piston (41) supplies pressure medium into the pressure chamber (22), thus a smaller actuating travel resulting at the brake pedal (16). If the auxiliary pressure is lacking upon a brake application, the secondary cylinder piston (41) will remain in its rest position and a sufficient braking action will be achievable by means of the master cylinder piston (19) smaller surface actuated alone. |
