Patents by Inventor Cynthia M. Gardner

Cynthia M. Gardner 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).

  • Patent number: 5899008
    Abstract: An apparatus for controllably moving a work implement. The implement is connected to a work machine and is moveable in response to the operation of a hydraulic cylinder. The apparatus includes an operator controlled joystick that generates an operator command signal, which is indicative of a desired velocity of the work implement movement. Cylinder position sensors produce cylinder position signals in response to the position of lift and tilt cylinders. A valve assembly receives an electrical valve signal, and controllably provides hydraulic fluid flow to the respective hydraulic cylinders to move the cylinders in accordance with the operator command signal. A controller receives the operator command and cylinder position signals, and responsively produces a pump command signal to change the displacement of a variable displacement pump to regulate the movement of the hydraulic cylinders.
    Type: Grant
    Filed: May 22, 1997
    Date of Patent: May 4, 1999
    Assignee: Caterpillar Inc.
    Inventors: Michael A. Cobo, Cynthia M. Gardner, James E. Schimpf
  • Patent number: 5875701
    Abstract: An apparatus for controllably moving a work implement is disclosed. The implement is connected to a work machine and is moveable in response to operation of a hydraulic cylinder. The apparatus includes an operator controlled joystick. A joystick position sensor senses the position of the joystick and responsively generates an operator command signal. Boom and bucket angle sensors sense the position of the work implement and responsively produces an boom angle signal and a bucket angle signal respectively. A microprocessor based controller receives the boom angle, bucket angle, and operator command signals, modifies the operator command signal, and produces an electrical valve signal in response to the modified operator command signal. An electrohydraulic valve receives the electrical valve signal, and controllably provides hydraulic fluid flow to the hydraulic cylinder in response to a magnitude of the electrical valve signal.
    Type: Grant
    Filed: June 9, 1997
    Date of Patent: March 2, 1999
    Assignee: Caterpillar Inc.
    Inventors: Michael A. Cobo, Hans P. Dietz, Cynthia M. Gardner, Robert E. Stone
  • Patent number: 5701793
    Abstract: An apparatus for controllably moving a work implement is disclosed. The implement is connected to a work machine and is moveable in response to operation of a hydraulic cylinder. The apparatus includes an operator controlled joystick. A joystick position sensor senses the position of the joystick and responsively generates an operator command signal. An implement position sensor senses the position of the work implement and responsively produces an implement position signal. A microprocessor based controller receives the implement position and operator command signals, modifies the operator command signal, and produces an electrical valve signal in response to the modified operator command signal. An electrohydraulic valve receives the electrical valve signal, and controllably provides hydraulic fluid flow to the hydraulic cylinder in response to a magnitude of the electrical valve signal.
    Type: Grant
    Filed: June 24, 1996
    Date of Patent: December 30, 1997
    Assignee: Catepillar Inc.
    Inventors: Cynthia M. Gardner, Robert E. Stone, John D. Duffy, William E. Allen, James E. Schimpf