Patents by Inventor Yohsiyuki Kawano

Yohsiyuki Kawano has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6780255
    Abstract: A magnetic powder of an Sm—Fe—N alloy, which has a mean particle diameter of 0.5 to 10 &mgr;m, and either an average acicularity of 75% or above or an average sphericity of 78% or above. The powder exhibits an extremely high residual magnetization and an extremely high coercive force, since particles characterized by the above acicularity or sphericity have particle diameters approximately equal to that of the single domain particle and nearly spherical particle shapes. The powder can be produced by preparing an Sm—Fe oxide by firing a coprecipitate corresponding to the oxide, mixing the obtained oxide with metallic calcium and subjecting the mixture to reduction/diffusion and nitriding successively.
    Type: Grant
    Filed: November 13, 2001
    Date of Patent: August 24, 2004
    Assignee: Nichia Chemical Industries, Ltd.
    Inventors: Yohsiyuki Kawano, Michiya Kume, Keiji Ichinomiya
  • Patent number: 6334908
    Abstract: A magnetic powder of an Sm—Fe—N alloy, which has a mean particle diameter of 0.5 to 10 &mgr;m, and either an average acicularity of 75% or above or an average sphericity of 78% or above. The powder exhibits an extremely high residual magnetization and an extremely high coercive force, since particles characterized by the above acicularity or sphericity have particle diameters approximately equal to that of the single domain particle and nearly spherical particle shapes. The powder can be produced by preparing an Sm—Fe oxide by firing a coprecipitate corresponding to the oxide, mixing the obtained oxide with metallic calcium and subjecting the mixture to reduction/diffusion and nitriding successively.
    Type: Grant
    Filed: June 23, 2000
    Date of Patent: January 1, 2002
    Assignee: Nichia Chemical Industries, Ltd.
    Inventors: Yohsiyuki Kawano, Michiya Kume, Keiji Ichinomiya