Patents by Inventor Stephen L. Grauel

Stephen L. Grauel 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).

  • Combined mounting for through-the-wall viewer and intercom
    Patent number: 4130728
    Abstract: Seeing and talking through a wall or closed door is conveniently provided by the combination of a one-way observation telescope projecting through the door and a pair of intercom units, one on each side of the door. Each intercom housing has a flange with a hole such that the units may be supported cooperatively by the telescope ends. Each housing may also have protruding tips against the door surface to prevent rotation of the housing.
    Type: Grant
    Filed: March 23, 1978
    Date of Patent: December 19, 1978
    Inventor: Stephen L. Grauel