Patents by Inventor Edward D. Duke

Edward D. Duke 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: 4128952
    Abstract: A chain tension maintenance device for use with the bowl loading elevator of the excavating scraper variety which is adjustable to vary the slack in the chain and paddle structure. At least one idler arm having bell crank geometry is pivotally mounted to the elevator frame through a first pivot point. An idler wheel axially mounted at a second pivot point of the idler arm, is urged into tension maintaining contact with the elevator chains by force exerted through the third pivot point of the idler arm by an adjustable turnbuckle grounded to the elevator frame.
    Type: Grant
    Filed: November 14, 1977
    Date of Patent: December 12, 1978
    Assignee: International Harvester Company
    Inventors: Edward D. Duke, Joan M. Riordan
  • Patent number: 4015681
    Abstract: Hydraulically operated steering systems normally supplied with fluid from an engine driven pump rely on an auxiliary pump upon failure of the primary pump. A ground driven pump incorporating a pressure sensing device automatically provides fluid to the power steering system in the event of an engine or primary pump failure.
    Type: Grant
    Filed: November 6, 1975
    Date of Patent: April 5, 1977
    Assignee: International Harvester Company
    Inventors: Daniel B. Shore, Edward D. Duke