Patents by Inventor Keith F. Hoffmann

Keith F. Hoffmann 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: 5434368
    Abstract: An apparatus for controlling use of electrically powered equipment includes an enclosure in which there is mounted an electrical connector receptacle which may be connected to a source of electrical power via its own power cable or plug blades. The enclosure is proportioned to receive the end of the electrical power cable or plug leads of one or more electrical power connectors of independently operated electrical devices. Plugging these devices into the electrical connector receptacle provides a direct, controlled connection to the power source. A locking device is provided on the exterior of the enclosure. This locking device could employ a variety of keyed and keyless lock designs. Disengaging the locking device unlocks the top enclosing lid of the enclosure to expose an electrical switch and a plurality of pins. When the electrical apparatus uses plug blades an attachment screw is also exposed to secure the electrical apparatus to the power source.
    Type: Grant
    Filed: October 6, 1993
    Date of Patent: July 18, 1995
    Inventor: Keith F. Hoffmann