Patents by Inventor Shuichi Shiina

Shuichi Shiina 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: 6383407
    Abstract: A ferrite powder for bonded magnets having a substantially magnetoplumbite-type crystal structure and an average diameter of 0.9-2 &mgr;m, the ferrite powder having a basic composition represented by the following general formula: (A1−xRx)O.n[(Fe1−yMy)2O3] by atomic ratio, wherein A is Sr and/or Ba; R is at least one of rare earth elements including Y, La being indispensable; M is at least one element selected from the group consisting of Co, Mn, Ni and Zn; and x, y and n are numbers meeting the conditions of 0.01≦x≦0.4, [x/(2.6n)]≦y≦[x/(1.6n)], and 5≦n≦6, (Si+Ca) being 0.2 weight % or less, and (Al+Cr) being 0.13 weight % or less, can be produced by mixing iron oxide containing 0.06 weight % or less of (Si+Ca) and 0.
    Type: Grant
    Filed: February 16, 2001
    Date of Patent: May 7, 2002
    Assignee: Hitachi Metals, Ltd.
    Inventors: Yasunobu Ogata, Yutaka Kubota, Takashi Takami, Shuichi Shiina
  • Publication number: 20010023933
    Abstract: A ferrite powder for bonded magnets having a substantially magnetoplumbite-type crystal structure and an average diameter of 0.9-2 &mgr;m, the ferrite powder having a basic composition represented by the following general formula: (A1-xRx)O.n[(Fe1-yMy)2O3] by atomic ratio, wherein A is Sr and/or Ba; R is at least one of rare earth elements including Y, La being indispensable; M is at least one element selected from the group consisting of Co, Mn, Ni and Zn; and x, y and n are numbers meeting the conditions of 0.01≦x≦0.4, [x/(2.6n)]≦y≦[x/(1.6n)], and 5≦n≦6, (Si+Ca) being 0.2 weight % or less, and (Al+Cr) being 0.13 weight % or less, can be produced by mixing iron oxide containing 0.06 weight % or less of (Si+Ca) and 0.
    Type: Application
    Filed: February 16, 2001
    Publication date: September 27, 2001
    Inventors: Yasunobu Ogata, Yutaka Kubota, Takashi Takami, Shuichi Shiina
  • Patent number: 6284150
    Abstract: A ferrite powder for bonded magnets having a substantially magnetoplumbite-type crystal structure and an average diameter of 0.9-2 &mgr;m, the ferrite powder having a basic composition represented by the following general formula: (A1-xRxO.n[Fe1-yMy)2O3] by atomic ratio, wherein A is Sr and/or Ba; R is at least one of rare earth elements including Y, La being indispensable; M is at least one element selected from the group consisting of Co, Mn, Ni and Zn; and x, y and n are numbers meeting the conditions of 0.01≦x≦0.4, [x/(2.6n)]≦y≦[x/(1.6n)], and 5≦n≦6, (Si+Ca) being 0.2 weight % or less, and (Al+Cr) being 0.13 weight % or less, can be produced by mixing iron oxide containing 0.06 weight % or less of (Si+Ca) and 0.
    Type: Grant
    Filed: September 23, 1999
    Date of Patent: September 4, 2001
    Assignee: Hitachi Metals, Ltd.
    Inventors: Yasunobu Ogata, Yutaka Kubota, Takashi Takami, Shuichi Shiina
  • Patent number: 4604042
    Abstract: A mold for producing an anisotropic magnet from a composition essentially consisting of magnetic powder and a binder, a mold body, a cavity for molding the composition in the presence of an anisotropically oriented magnetic field produced by a plurality of first magnets for providing magnetic fluxes for the magnetic field in the cavity, yokes, each provided between the cavity and the first magnets, and second magnets provided on both circumferential sides of the yokes for preventing the leakage of the magnetic fluxes. The first and second magnets are made of permanent magnets such as rare earth cobalt magnets. The mold may be provided at both ends with third magnets for preventing the axial leakage of the magnetic flux from the axial ends of the yokes. Two or more molds may be combined in a single molding apparatus while sharing the first magnets. This mold is suitable for the injection, extrusion or insert molding of bonded magnet rolls, motor rotors, etc.
    Type: Grant
    Filed: June 7, 1984
    Date of Patent: August 5, 1986
    Assignee: Hitachi Metals, Inc.
    Inventors: Shigeho Tanigawa, Shuichi Shiina, Kimio Uchida