Patents by Inventor Robert Dean Callahan

Robert Dean Callahan 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: 6123495
    Abstract: The transport includes a U-shaped chassis frame supported on wheels and a lift frame vertically movable within the chassis such that the lift frame can rest on the ground and move above the chassis frame. A plurality of winches are located on the lift frame and are driven in common through a step-down gear mechanism powered by a hand crank. Each winch includes a strap having a free end and a fixed end attached to the winch. The free end includes a fastener for temporarily attaching the strap to the chassis frame. Near each winch is a riser attached to the chassis frame and the strap from the winch passes over the riser to enable the lift frame to be raised slightly higher than the chassis frame.
    Type: Grant
    Filed: June 16, 1998
    Date of Patent: September 26, 2000
    Assignee: Robertson Aviation L.L.C
    Inventors: Robert Dean Callahan, Gary Bruce Robertson