Patents by Inventor John C. Stephenson

John C. Stephenson 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).

  • Master/slave hydraulic system with rebound compensation
    Patent number: 4825655
    Abstract: A master/slave hydraulic system (10) comprises a master cylinder (12), slave cylinders (14-22), and a rebound compensator (72) for eliminating the effects of expansibility in the system on the lower stroke of the cylinders so that accurate depth control across an agricultural implement can be achieved and maintained. The rebound compensator (72) includes a direct pressure reducing and relieving valve (74) and a check valve (86). A flow restrictor (90) is preferably provided on the high-pressure supply port of the pressure reducing and relieving valve (74).
    Type: Grant
    Filed: October 2, 1986
    Date of Patent: May 2, 1989
    Inventors: Andrew F. Buchl, John C. Stephenson