Patents by Inventor Frederick C. Gernhard

Frederick C. Gernhard 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).

  • Blister pressure relief valve
    Patent number: 4757654
    Abstract: A valve is disclosed for venting and relieving pressure within a blister in built-up, multiple layer roof structure, which includes a hollow shaft having one open end adapted to be inserted into the blister and the other end covered by an air permeable, water impermeable membrane protected by a housing. The exterior of the shaft is threaded to permit penetration into the blister and holding of the valve. Air is vented through the membrane and out a passage provided in the housing.
    Type: Grant
    Filed: February 13, 1987
    Date of Patent: July 19, 1988
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Charles J. Korhonen, Frederick C. Gernhard