Patents by Inventor Franklin E. Davidson

Franklin E. Davidson 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).

  • Method of and apparatus for molding spigot rings on pipe sections and product of the method
    Patent number: 4134431
    Abstract: A pipe section is mounted in a horizontal position and upper and lower halves of a spigot ring mold are clamped to the spigot end. The lower mold half is provided with a port for receiving a nozzle of a hardenable liquid resin supply hose and the upper mold half is provided with vents. Resin is forced into the mold under pressure until some comes out of the vents. After the resin is hardened, the mold is removed.
    Type: Grant
    Filed: May 11, 1977
    Date of Patent: January 16, 1979
    Assignee: Owens-Corning Fiberglas Corporation
    Inventors: Franklin E. Davidson, Lee E. Pearson