Patents by Inventor Charles David Hackman

Charles David Hackman 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).

  • Spreader unit for multi-legged stands
    Patent number: 5823491
    Abstract: A spreader unit for controlling a multi-legged stand is presented comprising a hub having a central axis and a plurality of arms hinged to the hub to swing in radial planes with respect to the hub axis. A control shaft is mounted in the hub for rotation about the axis with a reversible gear drive between the shaft and arms so that rotation of the shaft swings the arms with respect to the hub in unison and vice versa. A control for locking the shaft against rotation with respect to the hub is provided to hold the arms in required spread positions with respect to the hub.
    Type: Grant
    Filed: March 7, 1996
    Date of Patent: October 20, 1998
    Assignee: Vitec Group PLC
    Inventors: Richard Arthur Lindsay, Charles David Hackman