Patents by Inventor Donald C. Wakefield, deceased

Donald C. Wakefield, deceased 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).

  • Actuator device for a hydraulic spool valve
    Patent number: 4526342
    Abstract: There is disclosed an actuation device for operating a hydraulic spool valve. The device includes a d.c. electric motor and a high-ratio gearbox. The output of the gearbox connects with the spool of the valve through a segmented rack and pitman pin or a rack and pinion arrangement. A control circuit for the electric motor includes position feed-back to permit accurate positioning of the spool. Further, spring means are included to bias the spool to its neutral position in the absence of a control signal or on occurrence of a fail condition.
    Type: Grant
    Filed: December 22, 1982
    Date of Patent: July 2, 1985
    Assignee: Kontak Manufacturing Co. Ltd.
    Inventor: Donald C. Wakefield, deceased