Patents by Inventor Gerbert O. Keller

Gerbert O. Keller 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: 4060902
    Abstract: A combination straight edge, T-square, level, ruler and guide is provided for use by craftsman such as paperhangers, carpenters, and the like. The tool includes a relatively wide elongated body formed with parallel straight edges along both long edges, a handle and a plurality of replaceable bubble vials for establishing vertical and horizontal lines. A detachable and adjustable T-bar is provided and is formed with a lip along one edge whereby the T-bar in one position is flush with the bottom edge of the body, and in another position the lip extends downwardly to engage an edge of the work, for example. The T-bar is also provided with replaceable vials as well as a handle so that it may be used independent of the main body of the tool.
    Type: Grant
    Filed: May 7, 1976
    Date of Patent: December 6, 1977
    Inventor: Gerbert O. Keller