Patents by Inventor Mathias C. Hess

Mathias C. Hess 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).

  • Device for raising level of manhole cover
    Patent number: 4976568
    Abstract: This invention relates to a spacer for a manhole cover for use in a manhole frame comprising a ring having a mounting surface adapted to sit on the top of a manhole cover frame. The ring has a seating surface for, in use, the seating of a manhole cover thereon. The seating surface is spaced radially inwardly of the mounting surface. The ring has a downwardly extending portion below the seating surface. The downwardly extending portion has a lesser outside diameter than the portion above said seating surface to enter into the manhole cover frame in use.
    Type: Grant
    Filed: April 2, 1990
    Date of Patent: December 11, 1990
    Assignee: The Hopper Foundry (1977) Limited
    Inventor: Mathias C. Hess