Patents by Inventor David E. Dugger

David E. Dugger 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).

  • Fire resistant duct access door for cooking equipment exhaust systems
    Patent number: 4913127
    Abstract: An access door (10) for cleaning grease from duct runs (26) in exhaust systems for kitchen cooking equipment (16). The access door (10) includes a collar (32) which is mounted at a selected location in a run of duct to provide an opening (46) for accessing the interior surfaces (30) of the duct. A fireproof cover (54) is releasably secured to the collar (32) by securing devices for selectively closing the collar opening. A seal (70) is interposed between the collar the cover, proximate the juxtaposed portions to prevent fire from escaping the duct through the collar opening when the cover is mounted thereon.
    Type: Grant
    Filed: March 21, 1989
    Date of Patent: April 3, 1990
    Inventor: David E. Dugger