Patents by Inventor Geoffrey H. May

Geoffrey H. May 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).

  • Helical gear pump with progressive interference between rotor and stator
    Patent number: 5120204
    Abstract: A helical gear pump is described in which the geometry of the stator and rotor are modified such that the interference is significantly more at the locations of the minor diameter d than the locations of the major diameter D of the rotor. The rotor is preferably plasma coated with modified chromium oxide and the base metal of the rotor is advantageously machined so that in the region of locations of major diameter D, the thickness of the plasma coating is less and, in the region of the locations of minor diameter d, the thickness of the plasma coating is greater than in the remainder of the rotor while allowing the interference to be significantly more at the locations of the minor diameter d than at the locations of the major diameter D.
    Type: Grant
    Filed: August 15, 1991
    Date of Patent: June 9, 1992
    Assignee: Mono Pumps Limited
    Inventors: Lindsay T. Mathewson, Geoffrey H. May