Patents by Inventor Reimi TABUCHI

Reimi TABUCHI 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: 12784945
    Abstract: A production method of a Sm—Fe—N-based rare earth magnet, enabling to stably impart sufficient anisotropy, is provided. The present disclosure provides a production method of a rare earth magnet, including preparing a raw material powder containing a magnetic powder (SmFeN powder 10) having a magnetic phase which contains Sm, Fe and N and at least partially has a crystal structure of at least either Th2Zn17 type or Th2Ni17 type, and pressure-sintering the raw material powder. In this production method, magnetic orientation is imparted to the raw material powder by applying a magnetic field before the pressure sintering, and the application of magnetic field is continued to maintain the magnetic orientation at least until the middle of the pressure sintering.
    Type: Grant
    Filed: March 21, 2023
    Date of Patent: November 3, 2026
    Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Masaaki Ito, Noritsugu Sakuma, Akihito Kinoshita, Reimi Tabuchi, Tomonori Inuzuka, Kunihiro Matsuyama, Masashi Harada
  • Patent number: 12322542
    Abstract: A Sm—Fe—N-based rare earth magnet more resistant to demagnetization than ever before, particularly at high temperatures, and a production method thereof are provided. The present disclosure presents a production method of a rare earth magnet, including mixing a SmFeN magnetic powder and a modifier powder to obtain a mixed powder, compression-molding the mixed powder in a magnetic field to obtain a magnetic-field molded body, pressure-sintering the magnetic-field molded body to obtain a sintered body, and heat-treating the sintered body, and a rare earth magnet obtained by the method. D50 of the magnetic powder is 1.50 ?m or more and 3.00 ?m or less, the content ratio of the zinc component in the modifier powder is 6 mass % or more and 30 mass % or less, and the heat treatment temperature is 350° C. or more and 410° C. or less.
    Type: Grant
    Filed: November 14, 2022
    Date of Patent: June 3, 2025
    Assignees: TOYOTA JIDOSHA KABUSHIKI KAISHA, NICHIA CORPORATION
    Inventors: Masaaki Ito, Reimi Tabuchi, Motoki Hiraoka, Hisashi Maehara
  • Patent number: 12191059
    Abstract: A Sm—Fe—N-based rare earth magnet more resistant to demagnetization than ever before in an environment where an external magnetic field is applied, particularly at high temperatures, and a production method thereof are provided. The present disclosure presents a production method of a rare earth magnet, including preparing a coated magnetic powder, compression-molding the coated magnetic powder in a magnetic field to obtain a magnetic-field molded body, pressure-sintering the magnetic-field molded body to obtain a sintered body, and heat-treating the sintered body, and a rare earth magnet obtained by the method. D50 of the magnetic powder in the coated magnetic powder is 1.50 ?m or more and 3.00 ?m or less, the content ratio of the zinc component in the coated magnetic powder is 3 mass % or more and 15 mass % or less, and the heat treatment temperature is 350° C. or more and 410° C. or less.
    Type: Grant
    Filed: November 14, 2022
    Date of Patent: January 7, 2025
    Assignees: TOYOTA JIDOSHA KABUSHIKI KAISHA, NICHIA CORPORATION
    Inventors: Masaaki Ito, Motoki Hiraoka, Reimi Tabuchi, Hisashi Maehara, Michiya Kume
  • Patent number: 11990260
    Abstract: The present invention is a method for producing a rare earth magnet, including preparing a magnetic powder and a modifier powder, mixing them to obtain a mixed powder, compression-molding the mixed powder in a magnetic field to obtain a magnetic-field molded body, and pressure-sintering the magnetic-field molded body to obtain a sintered body, wherein the magnetic powder includes a first particle group and a second particle group, the D50 values of the first particle group and the second particle group are denoted by d1 ?m and d2 ?m, respectively, d1 and d2 satisfy the relationship of 0.350?d2/d1?0.500, and the ratio between the total volume of the first particle group and the total volume of the second particle group is from 9:1 to 4:1; and a rare earth magnet obtained by the production method.
    Type: Grant
    Filed: November 1, 2022
    Date of Patent: May 21, 2024
    Assignees: TOYOTA JIDOSHA KABUSHIKI KAISHA, NICHIA CORPORATION
    Inventors: Masaaki Ito, Motoki Hiraoka, Reimi Tabuchi, Hisashi Maehara, Masanori Okanan
  • Publication number: 20230317327
    Abstract: A production method of a Sm—Fe—N-based rare earth magnet, enabling to stably impart sufficient anisotropy, is provided. The present disclosure provides a production method of a rare earth magnet, including preparing a raw material powder containing a magnetic powder (SmFeN powder 10) having a magnetic phase which contains Sm, Fe and N and at least partially has a crystal structure of at least either Th2Zn17 type or Th2Ni17 type, and pressure-sintering the raw material powder. In this production method, magnetic orientation is imparted to the raw material powder by applying a magnetic field before the pressure sintering, and the application of magnetic field is continued to maintain the magnetic orientation at least until the middle of the pressure sintering.
    Type: Application
    Filed: March 21, 2023
    Publication date: October 5, 2023
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Masaaki ITO, Noritsugu SAKUMA, Akihito KINOSHITA, Reimi TABUCHI, Tomonori INUZUKA, Kunihiro MATSUYAMA, Masashi HARADA
  • Publication number: 20230139716
    Abstract: The present invention is a method for producing a rare earth magnet, including preparing a magnetic powder and a modifier powder, mixing them to obtain a mixed powder, compression-molding the mixed powder in a magnetic field to obtain a magnetic-field molded body, and pressure-sintering the magnetic-field molded body to obtain a sintered body, wherein the magnetic powder includes a first particle group and a second particle group, the D50 values of the first particle group and the second particle group are denoted by d1 ?m and d2 ?m, respectively, d1 and d2 satisfy the relationship of 0.350?d2/d1?0.500, and the ratio between the total volume of the first particle group and the total volume of the second particle group is from 9:1 to 4:1; and a rare earth magnet obtained by the production method.
    Type: Application
    Filed: November 1, 2022
    Publication date: May 4, 2023
    Applicants: TOYOTA JIDOSHA KABUSHIKI KAISHA, NICHIA CORPORATION
    Inventors: Masaaki ITO, Motoki HIRAOKA, Reimi TABUCHI, Hisashi MAEHARA, Masanori OKANAN