Patents by Inventor Robert Malcolm Graham

Robert Malcolm Graham 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: 4108481
    Abstract: Bell and plain or beveled end pipe sections are joined together in sealing engagement by placing a gasket between the sections and in radial compression. Pipe whose cross sections may deviate from a true circle and whose diameters may range over a wide tolerance are joined together utilizing an economical gasket, without requiring extremely high assembly forces. A specific portion of the gasket is compressed by a novel compression rib which allows assembly of the system without excessive end force and yet maintains radial compression of the gasket over a wide range of tolerances.
    Type: Grant
    Filed: December 6, 1976
    Date of Patent: August 22, 1978
    Assignee: United States Pipe and Foundry Company
    Inventor: Robert Malcolm Graham