Patents by Inventor Martin Bridgewater

Martin Bridgewater 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 fabricating hollow, foam-filled, metal structural members
    Patent number: 3968561
    Abstract: A hollow structural member formed of thin sheet steel is formed with one or more longitudinal joints and the interior is filled with a rigid lightweight synthetic plastics foam such as polyurethane. Each joint includes folded lips or flanges which are designed to provide a restricted clearance or gap into which the foaming material penetrates and changes from a cellular to a non-cellular composition and also provides an adhesive bond at each joint and a moisture proof seal.
    Type: Grant
    Filed: November 18, 1974
    Date of Patent: July 13, 1976
    Inventors: Thomas Francis Oakes, Martin Bridgewater