Patents by Inventor Ralf Sch/a/ fer

Ralf Sch/a/ fer 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).

  • Circuit arrangement for operating a high-pressure gas discharge lamp
    Patent number: 4471269
    Abstract: A circuit arrangement for operating a high-pressure gas discharge lamp (14) with high frequency current in which a direct voltage is supplied to a transistor bridge (5 to 8) having a transverse branch in which is arranged a choke coil (13). The clock (switching) frequency of the transistor bridge is varied within each period of the AC mains alternating voltage in dependence upon the current derived from the AC mains voltage.
    Type: Grant
    Filed: December 8, 1982
    Date of Patent: September 11, 1984
    Assignee: U.S. Philips Corporation
    Inventors: Hans G. Ganser, Ralf Sch/a/ fer, Hans P. Stormberg