Abstract: A hydraulic skid-controlled brake system comprising a master cylinder (2) pressurizable by a hydraulic force booster (1). The master cylinder piston (5) is provided as a stepped piston, with the small piston step (14) cooperating with the booster piston (4) traversing an annular chamber (19). The large piston step (15) plunges into the annular chamber (19). When the brakes are applied, the pressure fluid flows from a brake circuit (22, 31) into the annular chamber (19) by way of a first pressure fluid conduit (18, 21) and in which a blocking valve (26) is provided. By way of a second pressure fluid conduit (33, 34, 47, 36) the pressure fluid flows from the annular chamber (19) into an intake reservoir (11) in which a current control valve including a blocking slide (35) is provided. The connection (33) to the annular chamber (19), in the brake releasing position, is closed by the large step (15) of the master cylinder piston (5 ).

Abstract: A slip-controlled brake system for automotive vehicles comprises a brake booster (1) acting on a tandem master cylinder (7, 7'), of pressure medium lines connecting the tandem master cylinder (7, 7') with the wheel brakes, as well as of controllable multi-directional valves (30, 31, 32, 37, 41, 50, 51, 53) in the pressure medium lines. The tandem master cylinder is composed of a push-rod piston (6, 42) of an intermediate piston (8), as well as of a resetting arrangement (23, 44). Further, an auxiliary pressure source (26), transducers for detecting the rotational behavior of the wheels, and electronic circuits for the evaluation of the measured values and for the generation of valve control signals are included in the brake system.

Abstract: A hydraulic brake system with slip control for automotive vehicles comprising a master cylinder (2) pressurizable by a hydraulic power booster (1), in which system valve(s) (31,27,32,28,33,23) are inserted between the master cylinder (2) and the wheel brakes (29,30,24,25) connected to the master cylinder (2) which allow pressure fluid removal from the wheel brakes (29,30,24,25) that can be replenished out of the pressure chamber (19) of the hydraulic power booster (1) by way of a change-over valve (36). A stroke limitation of the brake pedal (8) is effected during slip control. The end surface of the master cylinder piston (5) close to the working chamber (16) being larger than the is effective surface of the booster piston (4), and wherein a stepped piston is employed as master cylinder piston (5) with an annular surface (18) thereof being adapted to be acted upon in the actuating direction by the pressure prevailing in the working chamber (16).

Abstract: A hydraulic brake system with slip control for automotive vehicles, comprises a master cylinder (2) pressurizable by a hydraulic power booster (1), in which system valve members (39, 40, 43, 44, 47) are inserted between the master cylinder (2) and the wheel brakes (45, 46, 41, 42) connected thereto which serve to remove pressure fluid from the wheel brakes (41, 42, 45, 46). Pressure fluid taken from the wheel brakes (41, 42, 45, 46) is replenished out of the pressure chamber (6) of the hydraulic power booster (1). A stroke limitation of the brake pedal (7) is effected during slip control.

Abstract: A vehicle hydraulic brake system with slip control, wherein a master cylinder (2) is pressurizable by a hydraulic poser booster (1). Valve means (23, 24, 29, 28, 32, 33, 34, 35) are inserted between the master cylinder (2) and the wheel brakes (25, 26, 30, 31) connected to the master cylinder (2), which valve means serve to remove pressure fluid from the wheel brakes (30, 31, 25, 26). Pressure fluid taken from the wheel brakes is replenished out of the pressure chamber (10) of the hydraulic power booster (1). A stroke limitation of the brake pedal (8) is effected during slip control. To simplify the design of the braking pressure generator (1, 2), the end surface of the master cylinder piston (5) close to the working chamber (16) is larger than the effective surface of the booster piston (4), and that a stepped piston is employed as master cylinder piston (5), an annular surface of said master cylinder piston (5) being adapted to be acted upon by the pressure prevailing in the working chamber (16).

Abstract: A hydraulic brake system with slip control, in particular for automotive vehicles, comprising a master cylinder (2) actuatable by a hydraulic power booster (1), in which brake system valve means (23, 24, 28, 29, 32, 33, 34, 35) are inserted between the master cylinder (2) and the wheel brakes (25, 26, 30, 31), connected to the master cylinder (2) which allow to remove pressure fluid from the wheel brakes (25, 26, 30, 31), while the pressure fluid taken from the wheel brakes (25, 26, 30, 31) can be replenished out of the pressure chamber (10) of the hydraulic power booster (1), wherein the master cylinder piston (5) is designed as a stepped piston and an annular surface (18) of the master cylinder piston (5) remote from the working chamber (16) is adapted to be acted upon by the pressure of the working chamber (16), and wherein the chamber (19) confined by the annular surface (18) is connectible to an unpressurized supply reservoir (11) by way of a travel-responsively controllable valve (51).

Abstract: The present invention is related to an electric switch comprising a magnet and a reed contact which is actuatable by the magnetic force of the magnet. The reed contact is shielded relative to the magnetic field of the magnet by means of a bell of magnetic field absorbing material which is furnished with an opening in the switching range of the reed contact to permit switch actuation. Exact switching points at the reed contacts are achieved by this arrangement.

Abstract: A pressure control device to be inserted into a connection between a front wheel brake and a rear wheel brake which determines the rear brake hydraulic pressure in dependence upon front brake hydraulic pressure. The pressure control device provides a plurality of valve pistons hydraulically connected in parallel and displaceable by front axle hydraulic pressure in opposition to a control force. A predetermined change-over hydraulic pressure develops a braking pressure in the rear brake which is less than the front brake pressure. The valve pistons are provided by stepped pistons guided within stepped bores, each of which pistons provides smaller and larger effective pressure surfaces.

Abstract: A power brake unit for automotive vehicles comprising a valve adapted to meter fluid from an energy source into a booster chamber to act upon a booster piston arrangement. The booster piston arrangement includes a first booster piston and a second booster piston with the second booster piston being inoperative in the event of failure of the energy source. If the energy source fails, the pedal force is directly and mechanically transmitted from the brake pedal to the master cylinder piston via the first booster piston.

Abstract: An arrangement for controlling the admission of a hydraulic fluid to respective wheel brake actuating cylinders either from an auxiliary pressure source or from a master cylinder includes a pressure limiting valve and a hydraulically operatable switching valve including a valve body movable only when the auxiliary pressure source is fully operational from a first position in which it connects the master cylinder with the actuating cylinders to a second position in which it connects the auxiliary pressure source with the actuating cylinders and the master cylinder with the pressure limiting valve. The limiting pressure of the pressure limiting valve is adjusted in dependence on the brake pedal travel. The respective master cylinder piston carries a deflectable seal which permits fluid to flow past it in one direction but not in the opposite direction. The pressure at which the switching valve member moves into its second position has a predetermined level, preferably 1 to 2 bar gauge.

Abstract: In an auxiliary power assisted master cylinder arrangement for a vehicle brake system to generate a controlled brake pressure in associated wheel brake cylinders, there is provided a brake valve with a preceding servo travel simulator to effect a control of the wheel brake cylinders of a vehicle. In one construction of the arrangement, there is interposed between two master cylinder units a pedal-operable device including mechanical cross links connecting with the master cylinder units as well as another cross link connecting with the brake valve. The brake valve is movable into engagement with the servo travel simulator, while the pedal-operable device, under normal braking conditions, is acted upon by the controlled pressure from an auxiliary power source in opposition to the pedal pressure and includes a lock providing for interlocking of all mechanical links in the event of a failure of auxiliary power.

Abstract: An arrangement for controlling the supply of pressurized hydraulic fluid from a master cylinder and from a pressure source into hydraulic circuits leading to wheel brake actuating cylinders includes a valve device including a control piston acted upon by a spring-loaded auxiliary piston in one direction and by the pressure in a return conduit in the opposite direction. Upon brake pedal depression, hydraulic fluid pressure from the pressure source acts on the auxiliary piston in opposition to the spring force so that the auxiliary piston ceases to act on the control piston. Then, as hydraulic fluid is discharged from the brake actuating cylinders during antiskid control action, pressure builds up in the return conduit and propagates to the control piston to move the same into its open position in which it admits pressurized fluid from the pressure source to check valves which are acted upon in opposition to their opening by the tandem master cylinder pressures.

Abstract: A brake unit comprising a hydraulic booster unit connected to hydraulic auxiliary energy and controllable by a brake pedal via a control piston drives a master brake cylinder unit to supply brake pressure to wheel brake cylinders through at least one hydraulic line connected to an output of the master brake cylinder unit. A bypass line connected to the work chamber of the booster unit supplies a preliminary feed of the auxiliary energy to the wheel brake cylinders to overcome the brake clearance. A two way, two position changeover valve is connected to the hydraulic line, the bypass line and the wheel brake cylinders to connect during a braking operation either the bypass line or the hydraulic line to the wheel brake cylinders dependent on the pressure in the two lines. This brake unit requires only a few hydraulic connections external of the unit, has a single construction, has small dimensions, has exact operation and has quick response.

Abstract: The brake booster comprises a working piston for activation of a master cylinder piston and a transmitting piston having a greater diameter than the working piston in a tandem relationship with the working piston. A transmission pressure chamber is disposed between adjacent ends of the working piston and the transmission piston and a first valve arrangement is provided to load the transmission pressure chamber with pressure fluid or to relieve this chamber of pressure. A drive or actuating pressure chamber is disposed adjacent the other end of the transmission piston and a second valve arrangement is provided to load the drive pressure chamber with pressure fluid or to relieve this chamber of pressure. The first and second valve arrangements are controlled by the brake pedal and constructed in such a way that when the brake pedal is initially operated the brake pedal and the pistons come to a stop until all idle paths have been travelled.

Abstract: A hydraulic booster for a brake system comprising a booster piston, a pressure-control device, an annular piston bearing against the booster piston and a central piston which is movable within limits relative to the annular piston by the brake pedal and actuates the pressure-control device. In this arrangement, the central piston and the annular piston are adapted to be coupled together after the force of a spring is overcome whereupon these two pistons are movable as one. The central piston is permanently subjected to the pressure acting on the booster piston when the brake system is actuated.

Abstract: A power brake unit for automotive vehicles includes a brake valve to meter brake fluid from an auxiliary fluid source into a booster chamber to act upon a booster piston arrangement. The booster piston arrangement includes a first booster piston and a second booster piston, the latter being held in an operative position by the fluid from the auxiliary fluid source and being inoperative in the event of failure of the auxiliary fluid source. If the auxiliary fluid source fails, the brake pedal force is directly and mechanically transmitted from the brake pedal to the master cylinder piston.