Patents by Inventor Hirokazu MAKUTA

Hirokazu MAKUTA 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).

  • Publication number: 20240047104
    Abstract: A permanent magnet having excellent magnetic properties and a device including such a permanent magnet are provided. A permanent magnet consists of a sintered compact having a composition consisting of R: 23 to 27 wt % (R is a sum total of rare-earth elements including at least Sm), Fe: 22 to 27 wt %, Mn: 0.3 to 2.5 wt %, Cu: 4.0 to 5.0 wt %, and a remainder consisting of Co and unavoidable impurities, in which the sintered compact contains a plurality of crystal grains and grain boundary phases, and a concentration of Cu in at least a part of the grain boundary phases is 45 at % or higher.
    Type: Application
    Filed: July 18, 2023
    Publication date: February 8, 2024
    Inventors: Masaaki TAKEZAWA, Hiroaki MACHIDA, Teruhiko FUJIWARA, Hirokazu MAKUTA
  • Publication number: 20240021349
    Abstract: A permanent magnet having a high coercivity, a method for manufacturing such a permanent magnet, and a device using such a permanent magnet are provided. The permanent magnet has a composition represented by a below-shown Formula (1). Formula (1): (R1-xZrx)a(T1-yMy)bBc. In Formula (1); R is at least one element selected from rare earth elements; T is at least one element selected from a group consisting of Fe, Co and Ni; M is at least one element selected from a group consisting of Al, Si, Ti, V, Cr, Mn, Cu, Hf, Nb, Mo, Ta and W; and each of a, b and c indicates atomic %, and x and y indicate ratios of Zr and M, respectively; and they are numbers that satisfy below-shown Expressions, 5?a?12, b=100?(a+c), 0.1?c?20, 0.01?x?0.5, and 0.01?y?0.5.
    Type: Application
    Filed: December 8, 2021
    Publication date: January 18, 2024
    Inventor: Hirokazu MAKUTA
  • Publication number: 20230095210
    Abstract: A permanent magnet having excellent magnetic properties, and a device including such a permanent magnet are provided. A permanent magnet consists of a sintered compact having a composition consisting of, in a mass percentage composition, R: 23 to 27% (R is a rare-earth element including at least Sm); Fe: 22 to 27%; Mn: 0.01 to 2.5%; and a remainder consisting of Co and unavoidable impurities, in which the sintered compact contains a plurality of crystal grains and grain boundaries, an average crystal grain size (A. G.) of the crystal grains is equal to or larger than 100 ?m, and a coefficient of variation (C. V.) of crystal grain sizes is equal to or smaller than 0.60.
    Type: Application
    Filed: September 26, 2022
    Publication date: March 30, 2023
    Inventors: Hiroaki MACHIDA, Teruhiko FUJIWARA, Hirokazu MAKUTA
  • Publication number: 20210249165
    Abstract: A rare-earth cobalt permanent magnet having excellent magnetic characteristics, a method for manufacturing such a rare-earth cobalt permanent magnet, and a device including such a rare-earth cobalt permanent magnet are provided. A rare-earth cobalt permanent magnet consisting of 23 to 27 mass % of a rare-earth element R including Sm, 4.0 to 5.0 mass % of Cu, 22 to 27 mass % of Fe, 1.7 to 2.5 mass % of Zr, and a remainder consisting of Co and unavoidable impurities, in which the rare-earth cobalt permanent magnet includes a plurality of crystal grains and grain boundary parts, and a size of a cell structure constituting the crystal grain is 100 to 600 nm.
    Type: Application
    Filed: January 27, 2021
    Publication date: August 12, 2021
    Inventors: Hiroaki MACHIDA, Teruhiko FUJIWARA, Hirokazu MAKUTA, Chieko FUJIMOTO, Yu KANAMORI
  • Publication number: 20210241948
    Abstract: A rare-earth cobalt permanent magnet having excellent magnetic characteristics, a method for manufacturing such a rare-earth cobalt permanent magnet, and a device are provided. A rare-earth cobalt permanent magnet consists of, when a rear-earth element including at least Sm is represented by R, 23 to 27 mass % of R, 1.0 to 5.0 mass % of Cu, 18 to 25 mass % of Fe, 1.5 to 3.0 mass % of Zr, and a remainder consisting of Co and unavoidable impurities, in which the rare-earth cobalt permanent magnet includes a plurality of crystal grains and grain boundary parts, and a concentration of Cu is at least two times a concentration of Zr in the grain boundary parts.
    Type: Application
    Filed: January 11, 2021
    Publication date: August 5, 2021
    Inventors: Hirokazu MAKUTA, Hiroaki MACHIDA, Teruhiko FUJIWARA, Yu KANAMORI