Patents by Inventor Robert William Hubbard

Robert William Hubbard 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).

  • Calibration of crane load indicating arrangement
    Patent number: 4063649
    Abstract: A device for the calibration of the safe load indicating apparatus on cranes and derricks that have a pivoted, extensible boom luffed by a hydraulic ram. The device operates by combining electrical signals corresponding to the actual turning moment of the unloaded boom at given boom positions with generated calibration signals corresponding to the turning moment for the theoretical maximum load at the boom positions, by comparing these combined signals to the safe load signals from the crane's law generator unit and by adjusting the law generator unit accordingly.This invention relates to a method and apparatus for the calibration of safe load indicating apparatus for use with cranes, derricks and other lifting apparatus of the type having a pivoted, extensible boom which can be luffed by an hydraulic ram or other boom supporting means.
    Type: Grant
    Filed: November 5, 1975
    Date of Patent: December 20, 1977
    Assignee: Pye Limited
    Inventors: Robert William Hubbard, Timothy John Archer Davis
  • Crane load inidicating arrangement
    Patent number: 3965733
    Abstract: A crane safe load indicator combines signals representing the total loaded boom turning moment and the turning moment of the boom alone to derive a third signal representing the turning moment of the load alone. The third signal is compared with a signal representing the crane's maximum safe load moment to indicate available lifting capacity.
    Type: Grant
    Filed: May 10, 1974
    Date of Patent: June 29, 1976
    Assignee: Pye Limited
    Inventors: Bernard David Francis Hutchings, Robert William Hubbard