Patents by Inventor Eilef J. Ohlgren

Eilef J. Ohlgren 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).

  • Building construction lift apparatus
    Patent number: 4550807
    Abstract: A portable lift apparatus for use in building construction. Two vertical members with attached endless chains or cables move lift members to the top of a building. The lift members pivot to lay their load flat at the top of the building. The vertical members are detachably connected together by a dual universal joint mechanism. When this connection is detached, the device is as portable as a ladder.
    Type: Grant
    Filed: August 4, 1983
    Date of Patent: November 5, 1985
    Inventor: Eilef J. Ohlgren