Patents by Inventor David F. Graff

David F. Graff 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: 4000390
    Abstract: A microwave oven door is fabricated using a rectangular structural frame. The frame is composed of two horizontal extruded members which are fastened at their ends to vertical cast end caps. Each of the end caps includes a door latch arrangement for engaging strikers mounted on the oven cabinet. The frame positively contains a stiffening member which may further be attached to the frame by an adhesive. Fastened to the stiffening member is a capacitive seal which is free to flex at its periphery. The capacitive seal is circumscribed by a secondary seal which is attached to the frame.
    Type: Grant
    Filed: February 14, 1975
    Date of Patent: December 28, 1976
    Assignee: Hobart Corporation
    Inventor: David F. Graff
  • Patent number: 3995899
    Abstract: A microwave oven interlock is provided to prevent oven operation when the oven door is opened or unlatched. An oven mounted strike is unlatched by lifting a handle mounted at the bottom of the door to allow the door to open upwardly. The interlock is responsive to the initial unlatching movement of the strike to disable the oven even before the door is unlatched. A cam arrangement on the hinges of the door senses the opening of the door to prevent further oven operation.
    Type: Grant
    Filed: February 14, 1975
    Date of Patent: December 7, 1976
    Assignee: Hobart Corporation
    Inventors: Coy M. Tippy, David F. Graff