Patents Assigned to Hydraulic Inventions BV
  • Patent number: 6347515
    Abstract: The invention relates to a drive device for a hydraulic elevator, the device comprising an actuator (1) whose pressure chamber (1a) is connected to a pump (11) via a down duct (15) and via an up duct (16). A pressure accumulator (4) is connected to the down and up ducts (15, 16) via parallel ducts (15a, 16a), each duct having an electrically controlled valve (2, 2a; 6, 6a). While the elevator is moving downwards, hydraulic fluid is transferred from the pressure chamber (1a) to the accumulator (4) via the down duct (15) and the parallel duct (16a). While the elevator is moving upwards, hydraulic fluid is transferred from the accumulator (4) to the pressure chamber (1a).
    Type: Grant
    Filed: June 26, 2000
    Date of Patent: February 19, 2002
    Assignee: Hydraulic Inventions BV
    Inventor: Emile Kadoche