Patents Represented by Attorney, Agent or Law Firm Frankiln Gubernick
  • Patent number: 6282893
    Abstract: A hydraulic cylinder in which the cylinder head contains a motor-driven fluid pump, fluid reservoir, and a main control valve for the cylinder. The cylinder includes a transfer tube that extends through the center of the cylinder's piston and terminates within a hollow ported section of a piston rod. The cylinder head can additionally include two electrically-actuated pilot valves and two pilot-operated check valves. The pilot-operated check valves include structure that, in combination with passages in the cylinder head, cause both pilot-operated check valves to open when pressurized fluid is being directed to one of the pilot-operated check valves by the main control valve.
    Type: Grant
    Filed: November 1, 1999
    Date of Patent: September 4, 2001
    Assignee: Delaware Capital Formation, Inc.
    Inventors: Don B. Porter, Wayne D. Shapiro