Patents by Inventor Keith D. Earhart

Keith D. Earhart 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: 9824818
    Abstract: In a single phase transformer core and transformer, thin-strip metal is wound into multiple rings of different widths and arranged to define a ring-like structure having a stepped, substantially circular cross-section without any cuts or gaps in the magnetic path, or the core is wound from a tapered strip that is configured to define a substantially circular cross-section when wound, while in a three phase transformer core and transformer two inner frames, each made of one or more wound rings are arranged side-by-side and an outer frame of one or more rings is wound around the two inner frames, the core being covered with epoxy prior to winding coils on it.
    Type: Grant
    Filed: June 18, 2015
    Date of Patent: November 21, 2017
    Inventor: Keith D Earhart
  • Publication number: 20160020020
    Abstract: In a single phase transformer core and transformer, thin-strip metal is wound into multiple rings of different widths and arranged to define a ring-like structure having a stepped, substantially circular cross-section without any cuts or gaps in the magnetic path, or the core is wound from a tapered strip that is configured to define a substantially circular cross-section when wound, while in a three phase transformer core and transformer two inner frames, each made of one or more wound rings are arranged side-by-side and an outer frame of one or more rings is wound around the two inner frames, the core being covered with epoxy prior to winding coils on it.
    Type: Application
    Filed: June 18, 2015
    Publication date: January 21, 2016
    Inventor: Keith D. Earhart
  • Publication number: 20140197144
    Abstract: In a method and system for slitting thin strip magnetic steel such as transformer core material, a laser is mounted above the material and the material is wound from a pay-out reel to one or more take-up reels.
    Type: Application
    Filed: January 14, 2013
    Publication date: July 17, 2014
    Inventors: Keith D. Earhart, John S. Hurst
  • Publication number: 20140111297
    Abstract: In a transformer core and transformer, a wound transformer core is formed from magnetic steel strips that are wound into multiple rings of different widths and arranged to define a ring-like structure having a stepped, substantially circular cross-section without any cuts or gaps in the magnetic path, or the core is wound from one or more tapered strips that are wound to define a cross-section that is circular, oval, egg-shaped, or square-shaped with truncated corners.
    Type: Application
    Filed: October 18, 2012
    Publication date: April 24, 2014
    Inventors: Keith D. Earhart, John S. Hurst