Patents Assigned to Fuji Jiko Kabushiki Kaisha
  • Patent number: 4575702
    Abstract: A permanent magnetic chuck in which a workpiece holding plate comprises a plurality of permanent magnets each with a magnetic isolator which are alternatively laminated, said magnetic pole pieces and said magnetic isolator are respectively constructed as layers of a plurality of thin magnetic layers and a plurality of thin non-magnetic layers each of which is disposed alternately with each of said magnetic layers; and a sliding magnet member which comprises a plurality of disk-shaped permanent magnets disposed in round holes provided in said member at the same pitch as the lamination pitch of the workpiece holding plate is disposed. The permanent magnets of the workpiece holding plate are so disposed that the same magnetic poles of the adjacent magnets are opposed to each other. The permanent magnets of the sliding magnet member are so disposed that the magnetic lines of flux pass vertically and that the opposite magnetic poles of the adjacent permanent magnets are opposed to each other.
    Type: Grant
    Filed: May 22, 1984
    Date of Patent: March 11, 1986
    Assignee: Fuji Jiko Kabushiki Kaisha
    Inventors: Takeshi Nitta, Hiroshi Iwasaki