Patents by Inventor Rex T. Humphreys

Rex T. Humphreys 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).

  • Speed override control for hydraulic motors
    Patent number: 3972186
    Abstract: A hydraulic system including a source of pressurized fluid and a multi-speed motor with a directional control valve for selectively directing fluid to the motor for forward and reverse operation thereof and a speed control valve operative to control the flow of the fluid to the motor for selective control of the speed thereof is provided with an override control valve that is operative to override the speed control valve under heavy load conditions to shift the speed control valve to a low-speed high-torque position for low-speed high-torque operation of the hydraulic motor.
    Type: Grant
    Filed: February 28, 1975
    Date of Patent: August 3, 1976
    Assignee: Caterpillar Tractor Co.
    Inventors: Rex T. Humphreys, Glenn J. Medina
  • Temperature-control arrangement for a pair of hydraulic motors
    Patent number: 3969897
    Abstract: A hydraulic system having a plurality of hydraulic motors operated by fluid from a common reservoir includes means for circulating a flow of fluid from the reservoir through the housing of the motors to thereby maintain a substantially equal temperature between the motors and the fluid.
    Type: Grant
    Filed: February 28, 1975
    Date of Patent: July 20, 1976
    Assignee: Caterpillar Tractor Co.
    Inventors: Rex T. Humphreys, Glenn J. Medina, Patrick A. Parker