Patents by Inventor Elmer L. Hoffmann

Elmer L. 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: 4889970
    Abstract: A liquid heater for use as a facial sauna or the like includes a conductive heating bowl, an electric heating element for heating the bowl and a terminal board as part of a circuit for control of the heating element. An integral, one-piece bracket is attached to the underside of the bowl, the bracket defining a plurality of arms having free ends extending outwardly from the bowl. The terminal board is carried by the arm in spaced relation from the bowl, typically at the edges of the board, to provide an air gap for thermal insulation of the board from the heat generated. The bracket also defines a tunnel positioned against the underside of the bowl, with the heating element occupying the tunnel.
    Type: Grant
    Filed: November 28, 1988
    Date of Patent: December 26, 1989
    Assignee: Schwalm Electronics Inc.
    Inventor: Elmer L. Hoffmann