Patents by Inventor Eric H. Pritchard

Eric H. Pritchard 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: 4105931
    Abstract: An inductor structure for use in a discharge lamp circuit has wound around at least part of its magnetic core first and second conducting foils. The first conducting foil is insulated from the magnetic core. The second conducting foil is interwound with but separated and insulated from the first conducting foil by a first dielectric foil and a second dielectric foil interwound with the conducting foils. The conducting foils have different numbers of turns. The conducting foil with the greater number of turns has all its turns except its excess turns wound oppositely to the turns of the other conducting foil. The structure provides a lower level of harmonic content above main frequency in the lamp and mains current waveforms.
    Type: Grant
    Filed: September 27, 1976
    Date of Patent: August 8, 1978
    Assignee: Thorn Electrical Industries Limited
    Inventors: Eric H. Pritchard, Thomas R. Passmore