Patents by Inventor Clyde R. Headrick

Clyde R. Headrick 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).

  • Hydraulic drive system for a vehicle
    Patent number: 4402181
    Abstract: A hydrostatic drive system having a closed loop front wheel drive circuit and a closed loop rear wheel drive circuit. A variable displacement pump in each of the circuits is cammed to vary the displacement delivered to dual displacement wheel motors to provide two speed ranges for the drive system. A servosystem uses hydraulic fluid to cam the displacement of the variable displacement pump and a hydraulic control to selectively engage each of the drive ranges.
    Type: Grant
    Filed: December 10, 1980
    Date of Patent: September 6, 1983
    Assignee: Allis-Chalmers Corporation
    Inventors: Alvin W. Acker, Clyde R. Headrick