Patents Assigned to Caper, Phillips & Associates
  • Patent number: 7500575
    Abstract: The present invention utilizes a hoist drum with a number of different diameter sections upon which the different ends of a lifting cable simultaneously spool on and off of as a function of counterclockwise and clockwise cable spooling. This combination reduces the amount of shaft torque required to raise or lower a load while increasing the number of hoist drum rotations required to raise or lower that load. These two features are incorporated into the operation of a main crane cable length adjusting device since they offer precise and rapid adjustment capabilities to be made with smaller sized electric motors and clutches.
    Type: Grant
    Filed: November 28, 2006
    Date of Patent: March 10, 2009
    Assignee: Caper, Phillips & Associates
    Inventor: Dianren Zhang