Patents by Inventor Peter Liermann

Peter Liermann has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4827415
    Abstract: An electropneumatic door control, particularly for the control of doors in public transportation, which includes for the purpose of detecting the respective position of the door linear motion sensors (1, 2) which are mounted on the pneumatic door cylinders (4, 5) or on the axes of rotation of the door wings, and whose output signals are evaluated by electronics (3). The electronics (3) include a computer which automatically detects the end positions as well as the motion behavior of the door or obstructions, respectively, and triggers a monitoring function, if necessary. The proposed door control increases reliability and eliminates previously used limit switches and electropneumatic differential pressure switches.
    Type: Grant
    Filed: February 15, 1983
    Date of Patent: May 2, 1989
    Assignee: WABCO Fahrzeugbremsen GmbH
    Inventors: Wolfgang Gudat, Peter Liermann, Jurgen Binarsch
  • Patent number: 4594571
    Abstract: 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.
    Type: Grant
    Filed: December 10, 1982
    Date of Patent: June 10, 1986
    Assignee: WABCO Fahrzeugbremsen GmbH
    Inventors: Detlev Neuhaus, Karl-Heinz Hesse, Gerhard Ruhnau, Peter Liermann
  • Patent number: 4584487
    Abstract: 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.
    Type: Grant
    Filed: October 2, 1984
    Date of Patent: April 22, 1986
    Assignee: WABCO Westinghouse Fahrzeugbremsen GmbH
    Inventors: Karl-Heinz Hesse, Peter Liermann, Detlev Neuhaus
  • Patent number: 4543575
    Abstract: An arrangement for providing electrical remote control of several magnetic solenoid valves having a transmitter section and a receiver section. The transmitter includes a fixed frequency signal generator for producing signals having an adjustable duty cycle. The duty cycle of the periodic signals varies in accordance with the position or deflection of an adjustable control lever. The periodic signals are transmitted over a first transmission link to the receiver section for controlling the condition of the magnet valves. A second transmission link is utilized for transmitting digital coded address information concerning which of the magnetic valves is to be selected in the receiver section in accordance with the position of the control lever in the transmitter section.
    Type: Grant
    Filed: February 24, 1983
    Date of Patent: September 24, 1985
    Assignee: WABCO Fahrzeugbremsen GmbH
    Inventor: Peter Liermann
  • Patent number: 4478131
    Abstract: 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.
    Type: Grant
    Filed: August 24, 1981
    Date of Patent: October 23, 1984
    Assignee: WABCO Fahrzeugbremsen GmbH
    Inventors: Peter Liermann, Karl-Heinz Hesse, Dietmar Meyer, Wolfgang Gudat
  • Patent number: 4273208
    Abstract: Signals representing actual and desired speeds of a vehicle are separately applied to a plurality of parallel comparator channels or devices. Each comparator device responds to a different level of difference between the speed signals, when actual is greater than desired, to produce output signals at successively higher levels. The first comparator device controls a first deceleration device, e.g., an exhaust throttle, to reduce vehicle speed when an output signal is produced at the first preselected level of difference. The second and third comparator devices control the second and third deceleration devices, respectively, e.g., an eddy-current brake, automatic transmission, etc., when each produces an output signal at its preselected difference level, but only if the next lower comparator output has enabled a gate or switch coupling the higher level comparator and deceleration devices.
    Type: Grant
    Filed: April 30, 1979
    Date of Patent: June 16, 1981
    Assignee: WABCO Fahrzeugbremsen GmbH
    Inventor: Peter Liermann
  • Patent number: 4225195
    Abstract: A process and apparatus for regulating the operator-controlled brake pressure of a vehicle wheel to prevent wheel lock-up by sensing a lock-up tendency and independently varying the operator-controlled brake pressure at the skidding wheel during successive cycles of wheel skid control. The sensed wheel behavior is monitored by an evaluation circuit which measures the duration of brake pressure reapplication with constant gradient during an initial cycle, provides a time period during a subsequent cycle that is a predetermined time duration less than the time duration of reapplication pressure in the initial cycle, and following expiration of the reduced time duration, establishes reapplication of pressure with a pressure gradient lower than the gradient during the initial cycle, whereby the reapplication pressure during control cycles subsequent to the initial control cycle is with a stepped gradient.
    Type: Grant
    Filed: May 26, 1978
    Date of Patent: September 30, 1980
    Assignee: Wabco Westinghouse GmbH
    Inventors: Lutz Weise, Peter Liermann
  • Patent number: 4205307
    Abstract: A first amplifier measures the instantaneous voltage across a resistor, connected in series with the electromagnet of a solenoid valve, as the current increases following energization of the electromagnet. A second amplifier measures the same voltage and stores the peak value in a capacitor. The two measured voltages are applied to a comparator which detects the difference, and generates an output, when operation of the electromagnet armature causes a transient reduction in the resistor voltage. Initial energization of the electromagnet sets a memory and starts a monostable timing period. The set output of the memory primes one input of an AND gate, the second input being inhibited by the monostable output during timing. If the electromagnet armature operates normally, the comparator output resets the memory and removes the AND gate priming signal prior to completion of the timing period.
    Type: Grant
    Filed: October 30, 1978
    Date of Patent: May 27, 1980
    Assignee: WABCO Westinghouse GmbH
    Inventors: Peter Liermann, Lutz Weise
  • Patent number: 4136912
    Abstract: 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.
    Type: Grant
    Filed: October 7, 1977
    Date of Patent: January 30, 1979
    Assignee: WABCO Westinghouse G.m.b.H.
    Inventors: Karl-Heinz Hesse, Gerhard Ruhnau, Wolfgang Gudat, Peter Liermann
  • Patent number: 4113322
    Abstract: 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.
    Type: Grant
    Filed: June 24, 1977
    Date of Patent: September 12, 1978
    Assignee: WABCO Westinghouse GmbH
    Inventors: Gerhard Ruhnau, Wolfgang Gudat, Peter Liermann, Karl-Heinz Hesse
  • Patent number: 4050747
    Abstract: 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.
    Type: Grant
    Filed: January 10, 1977
    Date of Patent: September 27, 1977
    Assignee: WABCO Westinghouse GmbH
    Inventors: Gerhard Ruhnau, Wolfgang Gudat, Peter Liermann, Karl-Heinz Hesse