Patents by Inventor Leonard L. Pollum

Leonard L. Pollum 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: 7165435
    Abstract: Work hardened sheets of formable metal are annealed by thermal conduction and heated to a forming temperature. In a preferred embodiment, the sheet is placed on a flat surface of a heated lower platen to partially heat and soften the sheet and an opposing heated upper platen is brought close enough to the sheet to contribute heat but not to constrain the sheet as it expands. The platens are then both brought close to the sheet to heat it to its forming temperature largely by thermal conduction.
    Type: Grant
    Filed: July 25, 2005
    Date of Patent: January 23, 2007
    Assignee: GM Global Technology Operations, Inc.
    Inventors: James G. Schroth, Richard H. Hammar, Paul E. Krajewski, Leonard L. Pollum, Susan Elizabeth Hartfield-Wunsch
  • Patent number: 7021099
    Abstract: The distortion-free removal of a heat softened sheet metal part from a heated forming surface is enabled by the elevation of lift pads in the forming surface. Strategically located and sized pads are recessed in the forming surface of the hot forming tool and the pads are part of the forming surface. At the completion of the stretch forming, or other hot forming, of a sheet metal blank on the forming surface, the pads are lifted in unison, without rotating them, on lift posts by a suitable lift mechanism to carefully and uniformly strip the flexible part from the hot forming surface.
    Type: Grant
    Filed: June 12, 2003
    Date of Patent: April 4, 2006
    Assignee: General Motors Corporation
    Inventors: Edward W. Bennett, Leonard L. Pollum, Gary A. Kruger
  • Publication number: 20040250585
    Abstract: The distortion-free removal of a heat softened sheet metal part from a heated forming surface is enabled by the elevation of lift pads in the forming surface. Strategically located and sized pads are recessed in the forming surface of the hot forming tool and the pads are part of the forming surface. At the completion of the stretch forming, or other hot forming, of a sheet metal blank on the forming surface, the pads are lifted in unison, without rotating them, on lift posts by a suitable lift mechanism to carefully and uniformly strip the flexible part from the hot forming surface.
    Type: Application
    Filed: June 12, 2003
    Publication date: December 16, 2004
    Inventors: Edward W. Bennett, Leonard L. Pollum, Gary A. Kruger