Patents by Inventor Helmut Roesch

Helmut Roesch 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).

  • Current limiting device
    Patent number: 6049447
    Abstract: A device for limiting overload currents using a semiconductor element with at least one controllable semiconductor having an electron source (source), an electron acceptor (drain) and a control electrode (gate) controlling the electron flow, which device has characteristic curves typical of a field-effect transistor (FET). In the case of alternating voltage, two FETs are connected in series, in complementary fashion. Arrangement is provided for internally obtaining the control voltage required for driving the semiconductor element from at least part of the load current and/or from at least part of the voltage drop across the semiconductor element.
    Type: Grant
    Filed: August 4, 1998
    Date of Patent: April 11, 2000
    Assignee: Siemens AG
    Inventors: Helmut Roesch, Hermann Zierhut
  • Current limiting device
    Patent number: 5999387
    Abstract: A device for limiting overload currents by means of a semiconductor element with at least one controllable semiconductor having an electron source (source), an electron acceptor (drain) and a control electrode (gate) controlling the electron flow, which device has characteristic curves typical of a field-effect transistor (FET). In the case of alternating voltage, two FETs are connected in series, in complementary fashion. Means are provided for internally obtaining the control voltage required for driving the semiconductor element from at least part of the load current and/or from at least part of the voltage drop across the semiconductor element.
    Type: Grant
    Filed: July 8, 1996
    Date of Patent: December 7, 1999
    Assignee: Siemens Aktiengesellschaft
    Inventors: Helmut Roesch, Hermann Zierhut