Patents Examined by Charles E. Echholdt
  • Patent number: 4987977
    Abstract: In a control apparatus for A.C. elevator, this invention consists in comprising a current control circuit which compares a current command of a brake coil current generated by a current command generator and an actual current thereof detected by a current detector, so as to control the brake coil current, whereby a riding quality of a cage is improved. This invention further comprises a velocity control circuit which adds a bias corresponding to a load in the cage, to a reference velocity command for the cage generated by a velocity command generator, whereby the riding quality of the cage is improved still further.
    Type: Grant
    Filed: November 1, 1989
    Date of Patent: January 29, 1991
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Masami Nomura