Patents Assigned to Rigaku Keisoku Kabushiki Kaisha
  • Magnetic fluid sealing device
    Patent number: 4605233
    Abstract: A magnetic fluid sealing device has a housing, a shaft accommodated in the housing, a plurality of permanent magnets disposed, in series, coaxially with each other, and polepieces disposed between the two adjoining magnets. The polepieces have one or more concave grooves to form a plurality of knife edges for concentrating magnetic flux. The density of magnetic flux passing through the edge or edges located adjacent to a vacuum environment is more increased than that through other edges.
    Type: Grant
    Filed: September 13, 1983
    Date of Patent: August 12, 1986
    Assignee: Rigaku Keisoku Kabushiki Kaisha
    Inventor: Kimio Sato