Patents Represented by Attorney J. F. James
  • Patent number: 4563721
    Abstract: The invention relates to a circuit arrangement for actuating exciting coils for electromagnetic switchgear. A transistor is connected in series with the exciting coil, as an electronic switch. Parallel with the series connection are a capacitor and a clock generator, which opens and closes the transistor with a certain frequency. Thereby, upon opening, a defined turn-off delay of the electromagnetic switchgear, and upon switching on, with the use of a timing element which at first deactivates the clock generator, the effect of a d-c saver circuit for electromagnetic switchgear can be achieved.
    Type: Grant
    Filed: October 7, 1983
    Date of Patent: January 7, 1986
    Assignee: Siemens Aktiengesellschaft
    Inventor: Gerhard Schroether