Patents by Inventor Kenneth R. Duff

Kenneth R. Duff 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).

  • Amphibious motor-driven cycle
    Patent number: 4387661
    Abstract: An amphibious two-wheeled cycle having an occupant-receiving hull secured to and receiving a frame and provided with front and rear wheel wells, a steerable front wheel supported by the frame and partially received in the front wheel well, and a motor-driven rear wheel supported from the frame and partially received in the rear wheel well. The front wheel well is defined by a special unit which provides a substantially watertight continuation of the hull but which allows unimpeded turning movement of the front wheel about a steering axis for steering the vehicle on land.
    Type: Grant
    Filed: October 19, 1981
    Date of Patent: June 14, 1983
    Inventor: Kenneth R. Duff
  • Amphibious vehicle
    Patent number: D297825
    Type: Grant
    Filed: September 17, 1986
    Date of Patent: September 27, 1988
    Inventor: Kenneth R. Duff