Brake system control unit and speed sensor arrangement

摘要

A control unit of a vehicle brake system has a receive circuit for tapping and processing a digital signal provided by an active speed sensor for speed measurement on a vehicle wheel. The signal includes information concerning the speed of a pole wheel, which is arranged in front of the sensor, spaced therefrom by an air gap, and which rotates along with the wheel. The signal also includes an actual air gap value digitized in stages and comprising several bits. The control unit also has a comparator circuit for comparing the actual air gap value to a reference air gap value and for determining whether the actual air gap value exceeds the reference value by more than a defined tolerance value. An information circuit of the control circuit generates early warning information when the comparator circuit determines that the actual air gap value exceeds the reference value by more than the tolerance value.

主权项

1. A control unit for controlling a brake system of a vehicle, the control unit comprising a receiver circuit configured to process, using at least one data processor, a digital signal from an active rotational speed sensor, the digital signal including (i) rotational speed information of a pole wheel disposed in front of the active rotational speed sensor and spaced from the active rotational speed sensor by an air gap, the pole wheel being configured to rotate with a wheel of the vehicle, and (ii) an actual air gap value representing the air gap between the pole wheel and the active rotational speed sensor, the actual air gap value being digitized in a plurality of stages and including a plurality of bits; a comparator circuit configured to compare, using at least one data processor, the actual air gap value with a setpoint air gap value and to determine whether the actual air gap value exceeds the setpoint air gap value by more than a tolerance value; and an information circuit configured to generate, using at least one data processor, pre-warning information when the comparator circuit determines that the actual air gap value exceeds the setpoint air gap value by more than the tolerance value, and output the pre-warning information to at least one of a brake controller and a warning light of the vehicle.