Abstract: A brake system intended for automotive vehicles provided with a brake pressure transmitter (1) which is linked to the wheel brakes through pressure medium lines, and with sensors (19 to 22, 24) which are responsive to the brake pressure or to the behavior of rotation of the wheels and by means of which the braking effect at the wheels brakes is detectable. Furthermore, separating valves (SO.sub.1, SO.sub.2, SO.sub.3, SO.sub.4, SO.sub.HA ) for shutting off the flow of pressure medium in one switching position are incorporated in the pressure medium paths leading to the wheel brakes. A monitoring circuit (3', 25') to which the sensor signals are transmittable recognizes the failure of one wheel brake and thereupon automatically commutates the separating valve located in the pressure medium path leading to the wheel brake which has failed into a valve position locking the flow of pressure medium.

Abstract: A brake system with anti-lock control and/or traction slip control is disclosed including a hydraulic braking pressure generator, a central plunger system, separating valves between the braking pressure generator and the plunger system as well as wheel valves. Further, there is provided an electronic controller which serves to modulate during a control action the braking pressure in the wheel brakes by actuation of the central plunger system and the wheel valves according to the so-termed Multiplex method. The system includes a braking pressure modulator substantially composed of the plunger system, an electric drive motor which is coupled to the plunger system by a single or double unit of planets and a worm drive.

Abstract: A device for controlling the pressure in an auxiliary-pressure supply system of a hydraulic brake unit for automotive vehicles, which device comprises a diaphragm-type or bladder-type accumulator equipped with a hydraulic and electric switching arrangement by way of which the hydraulic pressure in the pressure accumulator can be reduced to a predetermined value after the engine of the vehicle has been turned off. An electromagnetic multidirectional control valve is used to divert hydraulic fluid back to a reservoir through a pressure-limiting valve connected downstream thereof. After the engine of the vehicle has been turned off, the multidirectional control valve remains open until the accumulator pressure has decreased to at least the gas inflation pressure of the accumulator. The invention reduces permeation of gas molecules through the diaphragm of the accumulator into the hydraulic fluid and thus effects a longer useful life of the pressure accumulator.

Abstract: For traction control, the wheel slip is determined by comparing the rotational velocity of the driven wheels with the rotational velocity of the non-driven wheels or with a reference quantity. In a wheel tending to spin up, the driving slip is reduced by a braking action. By logically combining the signals reflecting the rotational velocity of the wheel and taking into account the control process already initiated, the desired accelerator value or the deviation therefrom is determined and signaled to the vehicle operator. By observing the indicating instrument (26, 31), the vehicle operator is in a position to actuate the accelerator pedal in such a manner that a mere braking action will produce an optimum driving and starting slip and thus an optimum traction of the vehicle, without the risk of a brake overload condition occurring.

Abstract: A device for testing the correct functioning of a slip-controlled brake system is connected to the electric signal and control lines of the brake system by means of a multiconductor plug (2) instead of a central electronic controller pertaining to the brake system. The individual testing operations are initiated one after the other from a control panel or manual control unit (1) by means of a test step switch (11). Disposed in immediate proximity to the multiconductor plug (2) or combined with the latter in a single unit is a shell (3) containing electric or electronic switches or circuits (5,6,7) which can be switched over by means of signals triggered from the control unit (1) for carrying out the testing operations.