Patents Assigned to Hydraulic Units, Inc.
  • Patent number: 4928028
    Abstract: A direct current linear drive actuator including first and second electromagnets, each having a cup-shaped ferromagnetic stator core with an axially extending concentric annular main pole member on the centerline thereof. First and second independent stator coils are recieved within the annular recesses of the stator cores. The open ends of the stator cores face one another with a washer-shaped ferromagnetic common pole member, positioned intermediate the open ends in perpendicular relation to the stator main poles. The armature is spring biased to a neutral position and includes a disc-shaped permanent magnet configured for being received within the inner opening of the common pole and is sandwiched between first and second disc-shaped pole members, each having an overall configuration sufficient to overlap the perimeter of the common pole in the radial direction. Air gaps are formed between the stator poles and the armature poles.
    Type: Grant
    Filed: February 23, 1989
    Date of Patent: May 22, 1990
    Assignee: Hydraulic Units, Inc.
    Inventor: Gregory Leibovich