Abstract: A process for compensating systematic errors of an acceleration sensor. The result of a sliding average of the output of the accelerometer, determined when acceleration in the primary measurement direction is zero, is subtracted from the output of the accelerometer thus producing a signal representative of acceleration only in the primary direction. A functional check of the accelerometer is provided by aligning the accelerometer in a second direction and comparing the acceleration measured in this second direction to the acceleration measured in the primary direction by a second device for determining acceleration and indicating a malfunction when the two measured accelerations are different and it is determined that acceleration only in the primary direction is present.

Abstract: In an antilock braking system (ABS) operating on the recirculating principle with a static brake circuit and a tandem master cylinder as the brake booster, a control stage is provided in order to lessen the intensity of reaction shocks noticeable at the brake pedal when the antilock control commences. From the onset of a pressure reduction signal, the control stage generates, for at least one brake-pressure control valve of the ABS, an operating voltage for the drive motor of the recirculating pump unit which rises with increasing duration of this signal. After a predetermined rising time, the voltage can reach a maximum value, correlated with maximum speed of the motor, and then is held at this value at least until dying-out, or otherwise rises to that value which is reached within the pressure-reduction signal duration.

Abstract: In a drive slip control device for a road vehicle, which is provided with an anti-lock system operating on the pump-back principle and having a return pump of the anti-lock system associated with the brake circuit of the driven vehicle wheels used as the auxiliary pressure source for the drive slip control, for braking a vehicle wheel tending to spin. When the drive slip control is activated, the main brake pipe of the brake circuit of the driven vehicle wheels is shut off from the brake unit by means of a drive slip control valve. The return pump is activated and is shut off from the brake unit until the drive slip of one of the driven vehicle wheels exceeds a threshold value whose magnitude lies between the drive slip required value and threshold response value. The brake pressure control valves of the brake circuit of the driven vehicle wheels are driven into their closed position by means of this anticipatory activation of the return pump.

Abstract: An anti-lock brake system (ABS) for a road vehicle is equipped with a wheel slip control system (ASR) and a hydraulic dual circuit brake system having front axle/rear axle brake static brake circuits, one brake circuit being allocated to the driven (rear) wheels of the vehicle and one to the non-driven (front) wheels. The system has two high-pressure pumps, one for each of the two brake circuits and which, in control phases of the ABS, brake fluid can be fed into the output pressure spaces of the brake unit and wherein the high-pressure pump allocated to the rear axle brake circuit is also utilized as auxiliary pressure source for the ASR. At the front axle brake circuit, the ABS operates on the feedback principle and at the rear axle brake circuit it operates on the discharge principle.