Patents Assigned to Nihon Digital Equipment Corporation
  • Method of and apparatus for driving three-phase D.C. brushless motor
    Patent number: 4864198
    Abstract: A three-phase D.C. brushless motor having a rotor and stator windings of three phases can be driven by alternately switching to the step of causing currents to flow through stator windings of only two phases among the stator windings of three phases or to the step of causing currents to flow through the stator windings of all the three phases each time the rotor rotates 30 degrees in terms of an electrical rotational angle, whereby torque fluctuation can be reduced.
    Type: Grant
    Filed: January 28, 1988
    Date of Patent: September 5, 1989
    Assignee: Nihon Digital Equipment Corporation
    Inventors: Shigeto Takase, Shigeaki Yamaguchi, Kentaro Ushioda