Patents by Inventor George W. Engel

George W. Engel 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).

  • Mailbox signalling device
    Patent number: 4163225
    Abstract: A device for signalling when a remote receptacle such as a rural mailbox has been opened. The device includes a switch that is closed by the opening of the box, a relay actuated thereby, a hold-in circuit established by the relay, a signalling means such as a buzzer or a light or both that is energized when the relay is actuated and a reset switch in the hold-in circuit for disabling the relay and the signalling means.
    Type: Grant
    Filed: July 5, 1977
    Date of Patent: July 31, 1979
    Inventor: George W. Engel