Patents by Inventor John S. Bruce

John S. Bruce 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).

  • Piston rings
    Patent number: 5068963
    Abstract: In the manufacture of a piston ring an intermediate ring is produced by bending a metal strip first to a smaller radius of curvature than required and then bending the metal strip again to increase its radius of curvature. The first and further bends are chosen to produce an intermediate ring, whereby the intermediate ring does not change shape when subjected to stress-relaxation temperatures, and has the required shape for the piston ring.
    Type: Grant
    Filed: July 10, 1990
    Date of Patent: December 3, 1991
    Assignee: T&N plc
    Inventor: John S. Bruce