Patents by Inventor David E. Lenhart

David E. Lenhart 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).

  • Powder metal forging and method and apparatus of manufacture
    Patent number: 9248503
    Abstract: A method of forming a powder metal forging, which includes the steps of providing a preform including a sintered powder metal composition; inserting the preform in at least one part of a die set having a top die and a bottom die, at least one of the top die and the bottom die defining a helical forge form therewithin; closing the die set wherein the top die is contacting the bottom die; and compressing the preform in the forge form using an upper punch including a core rod and a lower punch, the compressing step occurring after the closing step, the compressing step resulting in a formed part having a helical outer surface. The method and apparatus of the present invention is particularly advantageous when forming a powder metal forging helical outer surface and an inner contour such as a cylindrical inside diameter.
    Type: Grant
    Filed: April 1, 2008
    Date of Patent: February 2, 2016
    Assignee: GKN Sinter Metals, LLC
    Inventors: Alfred J. Chiesa, Hank J. Knott, David E. Lenhart
  • Powder forged differential gear
    Patent number: 8517884
    Abstract: A differential assembly, bevel gears for the assembly, and a method of making the bevel gears are disclosed. The bevel gears have a form which provides for high power density transfer.
    Type: Grant
    Filed: November 1, 2010
    Date of Patent: August 27, 2013
    Assignee: GKN Sinter Metals, LLC
    Inventors: Timothy E. Geiman, Alfred J. Chiesa, Henry J. Knott, David E. Lenhart
  • Powder Forged Differential Gear
    Publication number: 20110059822
    Abstract: A differential assembly, bevel gears for the assembly, and a method of making the bevel gears are disclosed. The bevel gears have a form which provides for high power density transfer.
    Type: Application
    Filed: November 1, 2010
    Publication date: March 10, 2011
    Inventors: Timothy E. Geiman, Alfred J. Chiesa, Henry J. Knott, David E. Lenhart
  • POWDER METAL FORGING AND METHOD AND APPARATUS OF MANUFACTURE
    Publication number: 20100083782
    Abstract: A method of forming a powder metal forging, which includes the steps of providing a preform including a sintered powder metal composition; inserting the preform in at least one part of a die set having a top die and a bottom die, at least one of the top die and the bottom die defining a helical forge form therewithin; closing the die set wherein the top die is contacting the bottom die; and compressing the preform in the forge form using an upper punch including a core rod and a lower punch, the compressing step occurring after the closing step, the compressing step resulting in a formed part having a helical outer surface. The method and apparatus of the present invention is particularly advantageous when forming a powder metal forging helical outer surface and an inner contour such as a cylindrical inside diameter.
    Type: Application
    Filed: April 1, 2008
    Publication date: April 8, 2010
    Inventors: Alfred J. Cheisa, Hank J. Knott, David E. Lenhart