Patents by Inventor Charles Greenhill

Charles Greenhill 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).

  • Crest-to-crest compression spring with circular flat shim ends
    Patent number: 4901987
    Abstract: A multiturn, crest to crest, waved compression spring is formed with flat circular shim end portions which form load support surfaces at opposite ends of the spring which are generally perpendicular to the spring longitudinal axis. The compression spring includes three distinct wave regions in which the first distinct wave region has a constant, preselected amplitude, the second distinct wave region has a gradually and incrementally diminishing amplitude and the third distinct wave region has a constant zero amplitude.
    Type: Grant
    Filed: May 3, 1988
    Date of Patent: February 20, 1990
    Assignee: Smalley Steel Ring Company
    Inventors: Charles Greenhill, Michael Greenhill