Patents by Inventor Walter J. Hansen

Walter J. Hansen 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: 4712653
    Abstract: An energy-recycling scissors lift includes a platform, base and a pair of scissors linkages, each having a first and second scissors legs. One end of each second scissors leg is pivotally attached to the base and the other end translations along the platform. One end of each first scissors leg is pivotally attached to the platform and the other end translates along the base. A bridge structure connects each of the second scissors legs together. A sealed gas cylinder, attached to the base and the bridge structure, moves the platform to an extended position above the base. Energy is stored in the sealed gas cylinder as the platform and supported object descends to a retracted position. A compensating device is attached to the scissors lift to compensate for the overforce caused by the sealed gas cylinder. One form of the compensating device adjusts the position of the sealed gas cylinder to vary the force exerted on the platform. Other compensating devices are equalizing springs and spring reels.
    Type: Grant
    Filed: August 14, 1985
    Date of Patent: December 15, 1987
    Assignee: Lift-R Technologies, Inc.
    Inventors: Duane R. Franklin, Archibald D. Evans, Walter J. Hansen