Wabco Westinghouse Gmbh

Wabco Westinghouse Fahrzeugbremsen Gmbh

Wabco Fahrzeugbremsen Gmbh

Karl-Heinz Hesse

Gerhard Ruhnau

Peter Liermann

Wolfgang Gudat

Detlev Neuhaus

Lutz Weise

Jens Groger

Wolfgang Lichtenberg

Dietmar Meyer

Rudolf Auding

Joachim Abel

Klaus Grubert

Michael Muller

A circuit for the surveillance of the switching state of a power transistor is constructed such that both, the voltage applied to the power transistor (1) is surveyed by way of a voltage comparator (7), as well as the voltage applied to the load (3) is surveyed by way of a further voltage comparator (8). The comparator (7) in the switched-on state and the comparator (8) in the switched-off state are activated by the input signal (U.sub.IN) of the power transistor (1). The output signals of the two comparators (7, 8) are combined to a status signal (U.sub.Stat). It is possible by way of the proposed circuit to recognize both a short circuit or, respectively, a shunt circuit of the load as well as a leakage current of the power transistor (1) and thus an interruption of the load occurs.

Circuitry for surveillance of switching state of a power transistor

The invention relates to an analog non-contact distance sensor which includes a fixed stationary annular magnetized armature. The stationary armature member is provided with an air gap into which is disposed an element which is sensitive to a magnetic field. The moving portion is a rod-shaped magnetic core member which can be inserted into the annular armature member. Depending on the depth of insertion of the core member, the amount of diversion of the magnetic field from the air gap of the armature is controlled. Consequently, the magnetic sensing element emits an electrical signal which corresponds to the distance travelled by the movable core member.

Magnetic-type of analog distance sensor having a hall effect sensing

A multiplex cabling system for controlling electrical apparatus on motor vehicles, which consists of a central transmitter and several area transmitter-receivers, each connected to several controlled devices and/or indicators. Coupling between the central transmitter and the area units is made by a star-arranged line system which consists of a separate, two-wire connecting channel between the central transmitter and each area transmitter-receiver. To further increase the system's reliability and security, the central transmitter includes two microprocessors which are normally assigned to control a different pair of diagonally-opposite area transmitter-receivers. If one processor fails, the other unit assumes full system control.

Multiplex cabling system for vehicles

A component control arrangement for transit-type vehicles having a distributed plurality of vehicle components to be monitored and controlled, includes a number of function control modules, each being associated with a specific vehicle function; as for example, wheel-skid, climate-control, and verification systems. The function control modules, each communicate in a multiplex arrangement over a shared data bus and a transceiver arrangement, with a distribution unit. The distribution units have an output configuration allowing connection to a variety of vehicle operating devices including lamps, switches, solenoid valves, and electric motors. The function control modules evaluate status indications originating from the vehicle operating devices and transmitted through the distribution units and a transceiver arrangement. The function control modules utilize the status indications to derive control instructions for the vehicle operating devices based on a predetermined set of vehicle operating and safety parameters.

Vehicle control arrangement for monitoring and controlling a plurality

An electro-pneumatic door control apparatus for use on public vehicles and including reversing mechanism for changing the direction of door movement, either automatically or operator-initiated, in the event of an obstruction in the door. The control apparatus further includes a flip-flop for recording the position (either open or closed) of the door at all times, a monitoring logic device for recognizing the position of the flip-flop and what type of monitoring function is permitted, a control logic device for picking up the door command and the signal from the monitoring logic device combing them and transmitting them to a valve solenoid control device for energizing respective solenoids of several valve devices by which the appropriate movement of the doors is effected.

Electro-pneumatic door control apparatus

An arrangement for monitoring the function of a programmable electronic switching circuit, such as, a microprocessor or microcomputer, characterized by a monitoring switch is associated with and is connected with the reset input and the clear input of the programmable electronic switching circuit and the monitoring switch includes a measuring circuit for determining the program length.

Arrangement for monitoring the function of a programmable electronic

This disclosure relates to a method and an arrangement for filtering disturbing signals in the digital measurement of the cycle duration for an antiskid control system for motor vehicles. The detrimental influence of short disturbances on the production of control signals is suppressed by means of the filtering process. The production of the control signals takes place in accordance with the result obtained from a comparison of the respective measured value .tau..sub.n with a reference value .tau..sub.B. The filtering is carried out in a manner so that when a digital measured value .tau..sub.n enters, a new reference value .tau..sub.B', is produced as a function of the difference between the reference value .tau..sub.B and the mean value obtained from the reference value .tau..sub.B and new measured value .tau..sub.n.

Method and arrangement for filtering digital, measured cycle-duration

An antiskid control system for a vehicle in which acceleration and deceleration control signals are generated by a control circuit in accordance with the rotational speed of a wheel monitored by a sensor device that produces a pulse train whose frequency varies with wheel speed. A digital counter operates for the duration of each pulse cycle of the sensor signal whereby the pulse count obtained represents a cycle duration of the sensor signal. Within the control circuit to which the sensor signal is supplied, a control unit transfers the pulse count after each cycle to a first shift register as a measure of the cycle duration. The first shift register outputs the pulse count of the measured cycle duration to a comparator to which there is also connected a pulse count of a reference cycle duration supplied by a second shift register to which the pulse count of a previous measured cycle duration has been supplied by the first shift register to form the reference cycle duration. The reference cycle duration and measured cycle durations are compared to obtain a difference signal which is subsequently compared to an admissible difference signal to provide the acceleration and deceleration control signals when the difference exceeds a preselected amount. The admissible difference is formed as a fraction of the reference cycle duration by selecting an output of the second shift register corresponding to a preselected stage thereof.

Digital control circuit for producing acceleration and deceleration

A checking circuit for periodically monitoring the electronic operating reliability of a vehicle antiskid control system during periods of operation, as well as prior to operation, by injecting a periodic test pulse into the system control channel. An evaluation circuit detects the transmission of the test pulse by the control channel and output amplifier as an indication of the ability of the electronic devices to effect a subsequent energization of the system modulator valve at the time of de-energization thereof, or de-energization of the system modulator valve at the time of energization thereof. A warning device is activated in the absence of a test pulse transmission within a predetermined time duration following generation thereof.

Circuit arrangement for periodically testing the operating reliability

A wheel speed measuring apparatus is provided for use in an anti-skid brake control system such that a digital speed signal is obtained having good accuracy without resorting to expensive manufacturing methods to assure exact conformity of the teeth and teeth spaces of the rotor member of the wheel sensor device used in the anti-skid control system. The speed measuring apparatus consists of at least two corresponding portions, each consisting of a control unit, a counter and a data register. The control unit of one portion responds to a positive polarity transition of the square wave signal generated by the wheel sensor, while the control unit of the other portion responds to negative polarity transitions, to initiate operation of the respective counters. The count output of each counter therefore provides a digital speed signal corresponding to a full cycle duration of the square wave signal, with one cycle overlapping the other to compensate for any deviations in the half-cycle durations due to size differences in the teeth and spaces of the rotor member of the sensor that generates the square wave signal.

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Gehrden, Germany

Karl-Heinz Hesse