Patents Examined by Johnson: R. B.
  • Lifting apparatus with hydraulic operated means to move a counterweight thereon
    Patent number: 3945518
    Abstract: A hydraulic circuit for moving a heavy article or counterweight is provided which includes a cylinder, a source of hydraulic pressure for supplying oil to the cylinder, and a bypass valve provided in a conduit for connecting the source to the cylinder. The bypass valve drains part of the oil supplied to the conduit when the pressure in the conduit drops below a predetermined value so as to smoothly move the heavy weight from first position to second position without shock.
    Type: Grant
    Filed: November 21, 1973
    Date of Patent: March 23, 1976
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventor: Kazuo Inoue