Patents by Inventor William H. Elder

William H. Elder 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).

  • Mechanical backlift
    Patent number: 4853990
    Abstract: A person-raising device, designed for lifting a person in bed, rests atop a bed and is activated by a linear actuator comprising a dual-threaded lead screw and a small electric motor and gear reduction unit. The small electric motor and gear reduction unit drives the dual-threaded lead screw to raise a pair of support arms, which raises a person resting on the device. The lead screw is enclosed in a slotted tube; this decreases the chance of the lead screw coming into contact with a person using the device.
    Type: Grant
    Filed: February 3, 1989
    Date of Patent: August 8, 1989
    Assignee: Mechanical Backrest, Inc.
    Inventors: William H. Elder, Ries B. Hansen, Andre W. Olivier