Patents by Inventor Thomas Pfeifer

Thomas Pfeifer 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: 4890491
    Abstract: A method and a device are provided for displaying the level of liquid in the fuel tank of an automotive vehicle. A liquid-level detector 1 and a display device 3 for indicating liquid level are included in the device. The measurement values of the liquid level are provisionally stored at predeterminable time intervals and compared with the instantaneous measurement values. During travel, increasing measurement values determined by the comparison are not displayed.
    Type: Grant
    Filed: August 4, 1988
    Date of Patent: January 2, 1990
    Assignee: VDO Adolf Schindling AG
    Inventors: Egon Vetter, Thomas Pfeifer, Heinz-Georg Burghoff, Werner Daub
  • Patent number: 4836027
    Abstract: In a circuit for a sensor the output signal of which is dependent not only on the variable to be determined but also on the temperature, an amplifier having a temperture-dependent amplification factor is connected to the output of the sensor, and the output of the amplifier is connected to an adder circuit to which a temperature-dependent voltage can be fed. The amplifier is preferably a differential amplifier within the feedback branch of which a temperature-dependent resistor is inserted. The adder circuit is preferably formed by another differential amplifier to the inputs of which the output signal of the differential amplifier with temperature-dependent amplification, the temperature-dependent voltage and a substantially temperature-independent voltage can be fed via resistors.
    Type: Grant
    Filed: November 20, 1987
    Date of Patent: June 6, 1989
    Assignee: VDO Adolf Schindling AG
    Inventors: Joachim Hannappel, Thomas Pfeifer
  • Patent number: 4833472
    Abstract: An arrangement for setting an analog resistor to a value which is digitally predetermined. The arrangement contains a resistor (2) which is variable by a control voltage as setting member of a control circuit, in series with a measurement resistor (3) and a rotary-magnet ratio meter (26). This series connection is fed from an operating voltage. The voltage at the measurement resistor (3) and the digital value are each fed to inputs of a multiplier (5) the outputs of which are connected via a digital/analog converter (6) to an input of a subtraction circuit (7). The other input of the subtraction circuit (7) is acted on by a reference voltage. The output of the subtraction circuit (7) produces the control voltage for the adjustable resistor (2).
    Type: Grant
    Filed: August 5, 1987
    Date of Patent: May 23, 1989
    Assignee: VDO Adolf Schindling AG
    Inventors: Joachim Hannappel, Thomas Pfeifer
  • Patent number: 4675255
    Abstract: A pole terminal is formed as an intermediate piece and has toward the bottom a clamping piece for fastening to a conventional battery pole and toward the top a pole body to which a conventional battery terminal can be fastened. In the pole terminal there are a Hall element and an evaluation electronics so that the current flow through the pole body can be measured.
    Type: Grant
    Filed: September 9, 1986
    Date of Patent: June 23, 1987
    Assignee: VDO Adolf Schindling AG
    Inventors: Thomas Pfeifer, Ivan Grgec-Messner