Patents Assigned to Kokka Kogyo Kabushiki Kaisha
  • Patent number: 4432441
    Abstract: A vibration isolation apparatus includes upper and lower, axially magnetized permanent magnets, which are disposed on a common axis and present poles of a like polarity on their opposing surfaces. The magnetic repulsion acting between the magnets maintains the upper one of them in suspension, on which is placed an instrument or member which is to be isolated from oscillations. In their central region, the magnets carry upper and lower bearing members which are disposed on the common axis and through which a connection shaft of a magnetizable material extends. The upper end of the connection shaft is provide with a flange, which is tightly fitted into a cylindrical opening formed in a threaded shank mounted on the upper magnet, thereby defining air damper to suppress a free oscillation of the upper magnet.
    Type: Grant
    Filed: March 10, 1982
    Date of Patent: February 21, 1984
    Assignee: Kokka Kogyo Kabushiki Kaisha
    Inventor: Masahito Kurokawa
  • Patent number: 4314623
    Abstract: A vibration isolator utilizes a force of magnetic repulsion which is produced by a pair of permanent magnets disposed so that poles of a like polarity oppose to each other. The vibration isolator includes an upper and a lower, annular magnet assembly which are axially magnetized and which are disposed coaxially on a common axis so that their opposing surfaces present poles of a like polarity. The respective magnet assemblies are covered, except for the opposing surfaces, by yoke members of a magnetizable material, whereby a magnetic flux is concentrated across the opposing surfaces of the magnetic assemblies to produce an increased force of magnetic repulsion therebetween. Bearing sleeves are disposed in the central region of each of the magnet assemblies. A connecting shaft has its opposite ends loosely fitted in the respective bearing sleeves, whereby one of the magnet assemblies is coupled to the other so as to be axially movable independently from each other.
    Type: Grant
    Filed: February 1, 1980
    Date of Patent: February 9, 1982
    Assignee: Kokka Kogyo Kabushiki Kaisha
    Inventor: Masahito Kurokawa