Patents by Inventor Noritsugu Sakuma

Noritsugu Sakuma 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: 20210375515
    Abstract: To provide an R—Fe—B-based rare earth magnet excellent in the squareness and magnetic properties at high temperatures, and a production method thereof. The present disclosure provides a rare earth magnet including a main phase 10 and a grain boundary phase 20 present. The overall composition of the rare earth magnet of the present disclosure is represented, in terms of molar ratio, by the formula: (R1(1-x)Lax)y(Fe(1-z)Coz)(100-y-w-v)BwM1v, wherein R1 is one or more predetermined rare earth elements, and M1 is one or more predetermined elements, and wherein 0.02?x?0.1, 12.0?y?20.0, 0.1?z?0.3, 5.0?w?20.0, and 0?v?2.0. The main phase 10 has an R2Fe14B-type crystal structure, the average particle diameter of the main phase 10 is from 1 to 10 ?m, and the volume ratio of a phase having an RFe2-type crystal structure in the grain boundary phase 20 is 0.60 or less relative to the grain boundary phase 20.
    Type: Application
    Filed: April 1, 2021
    Publication date: December 2, 2021
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Noritsugu SAKUMA, Tetsuya SHOJI, Yukio TAKADA
  • Publication number: 20210327620
    Abstract: A rare earth magnet includes a main phase and a particle boundary phase and in which an overall composition is represented by a formula, (R2(1-x)R1x)yFe(100-y-w-z-v)CowBzM1v.(R3(1-p)M2p)q.(R4(1-s)M3s)t, where R1 is a light rare earth element, R2 and R3 are a medium rare earth element, R4 is a heavy rare earth element, M1, M2, M3 are a predetermined metal element. The main phase includes a core portion, a first shell portion, and a second shell portion. The content proportion of medium rare earth element is higher in the first shell portion than in the core portion, the content proportion of medium rare earth element is lower in the second shell portion than in the first shell portion. The second shell portion contains heavy rare earth elements.
    Type: Application
    Filed: February 23, 2021
    Publication date: October 21, 2021
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Noritsugu SAKUMA, Tetsuya SHOJI, Akihito KINOSHITA
  • Publication number: 20210272751
    Abstract: The production method of a rare earth magnet of the present disclosure includes a coated magnetic powder preparation step, a mixed powder preparation step, and a pressure sintering step. In the coated magnetic preparation step, a zinc-containing coating 12 is formed on the particle surface of a samarium-iron-nitrogen-based magnetic powder to obtain a coated magnetic powder 14. In the mixed powder preparation step, a binder powder 20 having a melting point not higher than the melting point of the coating 12 and the coated magnetic powder 14 are mixed to obtain a mixed powder. In the pressure sintering step, denoting as T1° C. the temperature at which the peak disappears in an X-ray diffraction pattern of the binder powder 20 and as T2° C. the temperature at which the magnetic phase in the samarium-iron-nitrogen-based magnetic powder 10 decomposes, the mixed powder is pressure-sintered at T1° C. or more and (T2?50)° C. or less.
    Type: Application
    Filed: December 29, 2020
    Publication date: September 2, 2021
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Daisuke ICHIGOZAKI, Tatsuhiko HIRANO, Noritsugu SAKUMA, Akihito KINOSHITA, Masaaki ITO
  • Patent number: 11087922
    Abstract: A method for producing a rare earth magnet, including preparing a melt of a first alloy having a composition represented by (R1vR2wR3x)yTzBsM1t (wherein R1 is a light rare earth element, R2 is an intermediate rare earth element, R3 is a heavy rare earth element, T is an iron group element, and M1 is an impurity element, etc.), cooling the melt of the first alloy at a rate of from 100 to 102 K/sec to obtain a first alloy ingot, pulverizing the first alloy ingot to obtain a first alloy powder having a particle diameter of 1 to 20 ?m, preparing a melt of a second alloy having a composition represented by (R4pR5q)100-uM2u (wherein R4 is a light rare earth element, R5 is an intermediate or heavy rare earth element, M2 is an alloy element, etc.), and putting the first alloy powder into contact with the melt of the second alloy.
    Type: Grant
    Filed: April 13, 2018
    Date of Patent: August 10, 2021
    Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Masaaki Ito, Noritsugu Sakuma, Masao Yano, Hidefumi Kishimoto, Tetsuya Shoji
  • Publication number: 20210074455
    Abstract: A rare earth magnet 100 including a main phase 10 and a grain boundary phase 20. The overall composition is represented by the formula: (R2(1-x)R1x)yFe(100-y-w-z-v)CowBzM1v.(R3(1-p)M2p)q. R1 is an element selected from Ce, La, Y, and Sc. R2 and R3 is an element selected from Nd, Pr, Gd, Tb, Dy, and Ho. M1 is a predetermined element, etc. M2 is a transition metal element, etc. The average particle dimeter of the main phase 10 is from 1 to 20 ?m. The main phase 10 has a core portion 12 and a shell portion 14. The thickness of the shell portion 14 is from 25 to 150 nm. The “a” is the ratio of the light rare earth element of the core portion 12 and the “b” is the ratio of the light rare earth element of the core portion 12. These satisfy 0?b?0.30 and 0?b/a?0.50.
    Type: Application
    Filed: August 27, 2020
    Publication date: March 11, 2021
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Noritsugu SAKUMA, Tetsuya SHOJI, Yukio TAKADA
  • Publication number: 20210065973
    Abstract: A rare earth magnet including a magnetic phase having the composition represented by (Nd(1?x?y)LaxCey)2(Fe(1?z)Coz)14B. When the saturation magnetization at absolute zero and the Curie temperature calculated by Kuzmin's formula based on the measured values at finite temperature and the saturation magnetization at absolute zero and the Curie temperature calculated by first principles calculation are respectively subjected to data assimilation. The saturation magnetization M(x, y, z, T=0) at absolute zero and the Curie temperature obtained by machine learning using the assimilated data group are applied again to Kuzmin's formula and the saturation magnetization at finite temperature is represented by a function M(x, y, z, T), x, y, and z of the formula in an atomic ratio are in a range of satisfying M(x, y, z, T)>M(x, y, z=0, T) and 400?T?453.
    Type: Application
    Filed: August 24, 2020
    Publication date: March 4, 2021
    Applicants: TOYOTA JIDOSHA KABUSHIKI KAISHA, THE UNIVERSITY OF TOKYO
    Inventors: Kazuya YOKOTA, Tetsuya SYOJI, Noritsugu SAKUMA, Takashi MIYAKE, Yosuke HARASHIMA, Hisazumi AKAI, Naoki KAWASHIMA, Keiichi TAMAI, Munehisa MATSUMOTO
  • Patent number: 10937577
    Abstract: A magnetic compound represented by the formula (R1(1-x)R2x)a(Fe(1-y)Coy)bTcMd wherein R1 is one or more elements selected from the group consisting of Sm, Pm, Er, Tm and Yb, R2 is one or more elements selected from the group consisting of Zr, La, Ce, Pr, Nd, Eu, Gd, Tb, Dy, Ho and Lu, T is one or more elements selected from the group consisting of Ti, V, Mo, Si and W, M is one or more elements selected from the group consisting of unavoidable impurity elements, Al, Cr, Cu, Ga, Ag and Au, 0?x?0.7, 0?y?0.7, 4?a?20, b=100-a-c-d, 0<c<7.7, and 0?d?3, the magnetic compound having a ThMn12-type crystal structure, wherein the volume fraction of ?-(Fe, Co) phase is less than 12.3%.
    Type: Grant
    Filed: August 10, 2016
    Date of Patent: March 2, 2021
    Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Noritsugu Sakuma, Masao Yano, Akira Kato, Akira Manabe, Shunji Suzuki, Kurima Kobayashi
  • Patent number: 10910987
    Abstract: To provide a motor control method ensuring that dragging loss at the time of high rotation can be reduced. A motor control method, wherein a composite permanent magnet has a core part and a shell part, the Curie temperature of one of the core part and the shell part is Tc1 K, and the Curie temperature of another is Tc2 K, and wherein when the magnitude of the reluctance torque is equal to or greater than the magnitude of the magnet torque, the temperature of the composite permanent magnet is set at Ts K that is (Tc1?100) K or higher and lower than Tc2 K and when the magnitude of the reluctance torque is less than the magnitude of the magnetic torque, the temperature of the composite permanent magnet is set at lower than the temperature Ts K or Tc1 K, whichever is lower.
    Type: Grant
    Filed: July 2, 2019
    Date of Patent: February 2, 2021
    Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Noritsugu Sakuma, Masao Yano, Masaaki Ito, Tetsuya Shoji, Hidefumi Kishimoto, Akira Kato
  • Patent number: 10892076
    Abstract: A rare earth magnet includes a main phase, a grain boundary phase present around the main phase and an intermediate phase interposed between the main phase and the grain boundary phase, and has an overall composition that is represented by the formula ((Ce(1-x)Lax)(1-y)R1y)pT(100-p-q-r)BqM1r?(R21-zM2z)s (where, R1 and R2 are rare earth elements other than Ce and La, T is at least one selected from among Fe, Ni, and Co, M1 is an element having a small amount that does not influence magnetic characteristics, and M2 is an alloy element for which a melting point of R21-zM2z is lower than a melting point of R2). A total concentration of Ce and La is higher in the main phase than in the intermediate phase, and a concentration of R2 is higher in the intermediate phase than in the main phase.
    Type: Grant
    Filed: December 5, 2017
    Date of Patent: January 12, 2021
    Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Masaaki Ito, Noritsugu Sakuma, Tetsuya Shoji, Hidefumi Kishimoto, Masao Yano
  • Publication number: 20200303998
    Abstract: A method of producing a motor core includes preparing a soft magnetic plate containing a transition metal element, preparing a modifying member containing an alloy having a melting point lower than a melting point of the soft magnetic plate, bringing the modifying member into contact with a part of a plate surface of the soft magnetic plate, causing the modifying member to diffuse and penetrate into the soft magnetic plate from a contact surface between the soft magnetic plate and the modifying member and forming a hard magnetic phase-containing part in a part of the soft magnetic plate, and laminating a plurality of soft magnetic plates on each other after the modifying member is brought into contact with the part of the plate surface of the soft magnetic plate.
    Type: Application
    Filed: March 6, 2020
    Publication date: September 24, 2020
    Inventors: Akihito KINOSHITA, Noritsugu SAKUMA, Tetsuya SHOJI, Kosuke YONEKAWA
  • Patent number: 10748684
    Abstract: To provide a rare earth magnet ensuring excellent magnetic anisotropy while reducing the amount of Nd, etc., and a manufacturing method thereof. A rare earth magnet comprising a crystal grain having an overall composition of (R2(1-x)R1x)yFe100-y-w-z-vCowBzTMv (wherein R2 is at least one of Nd, Pr, Dy and Tb, R1 is an alloy of at least one or two or more of Ce, La, Gd, Y and Sc, TM is at least one of Ga, Al, Cu, Au, Ag, Zn, In and Mn, 0<x<1, y=12 to 20, z=5.6 to 6.5, w=0 to 8, and v=0 to 2), wherein the average grain size of the crystal grain is 1,000 nm or less, the crystal grain consists of a core and an outer shell, the core has a composition of R1 that is richer than R2, and the outer shell has a composition of R2 that is richer than R1.
    Type: Grant
    Filed: August 6, 2019
    Date of Patent: August 18, 2020
    Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Masaaki Ito, Masao Yano, Hidefumi Kishimoto, Noritsugu Sakuma, Tetsuya Shoji, Akira Manabe
  • Publication number: 20200098497
    Abstract: To provide a rare earth magnet in which particles of SmFeN powder are bound using a Zn powder, wherein generation of a knick at a magnetic field of around 0 is prevented and high residual magnetic flux density Br is thereby achieved, and a production method thereof. A rare earth magnet including a main phase containing Sm, Fe, and N, at least a part of the main phase having a Th2Zn17-type or Th2Ni17-type crystal structure, a sub-phase containing Zn and Fe and being present around the main phase, and an intermediate phase containing Sm, Fe and N as well as Zn and being present between the main phase and the sub-phase, wherein the average Fe content in the sub-phase is 33 at % or less relative to the whole sub-phase.
    Type: Application
    Filed: September 19, 2019
    Publication date: March 26, 2020
    Applicants: TOYOTA JIDOSHA KABUSHIKI KAISHA, TOHOKU UNIVERSITY
    Inventors: Noritsugu SAKUMA, Tetsuya SHOJI, Akihito KINOSHITA, Kazuaki HAGA, Daisuke ICHIGOZAKI, Yukio TAKADA, Satoshi SUGIMOTO, Masashi MATSUURA
  • Publication number: 20200098496
    Abstract: To provide a rare earth magnet in which particles of SmFeN powder are bound using a Zn alloy powder, wherein generation of a knick at a magnetic field of around 0 is prevented, and a production method thereof. A rare earth magnet including a main phase containing Sm, Fe, and N, at least a part of the main phase having a Th2Zn17-type or Th2Ni17-type crystal structure, a sub-phase containing at least either Si or Sm, and Zn and Fe and being present around the main phase, and an intermediate phase containing Sm, Fe and N as well as Zn and being present between the main phase and the sub-phase, wherein the average Fe content in the sub-phase is 33 at % or less relative to the whole sub-phase, and the average total content of Si and Sm in the sub-phase is from 1.4 to 4.5 at % relative to the whole subs-phase.
    Type: Application
    Filed: September 19, 2019
    Publication date: March 26, 2020
    Applicants: TOYOTA JIDOSHA KABUSHIKI KAISHA, TOHOKU UNIVERSITY
    Inventors: Akihito KINOSHITA, Noritsugu SAKUMA, Tetsuya SHOJI, Daisuke ICHIGOZAKI, Tatsuhiko HIRANO, Kazuaki HAGA, Yukio TAKADA, Satoshi SUGIMOTO, Masashi MATSUURA
  • Publication number: 20200036322
    Abstract: To provide a motor control method ensuring that dragging loss at the time of high rotation can be reduced. A motor control method, wherein a composite permanent magnet has a core part and a shell part, the Curie temperature of one of the core part and the shell part is Tc1 K, and the Curie temperature of another is Tc2 K, and wherein when the magnitude of the reluctance torque is equal to or greater than the magnitude of the magnet torque, the temperature of the composite permanent magnet is set at Ts K that is (Tc1?100) K or higher and lower than Tc2 K and when the magnitude of the reluctance torque is less than the magnitude of the magnetic torque, the temperature of the composite permanent magnet is set at lower than the temperature Ts K or Tc1 K, whichever is lower.
    Type: Application
    Filed: July 2, 2019
    Publication date: January 30, 2020
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Noritsugu SAKUMA, Masao YANO, Masaaki ITO, Tetsuya SHOJI, Hidefumi KISHIMOTO, Akira KATO
  • Publication number: 20190362870
    Abstract: To provide a rare earth magnet ensuring excellent magnetic anisotropy while reducing the amount of Nd, etc., and a manufacturing method thereof. A rare earth magnet comprising a crystal grain having an overall composition of (R2(1-x)R1x)yFe100-y-w-z-vCowBzTMv (wherein R2 is at least one of Nd, Pr, Dy and Tb, R1 is an alloy of at least one or two or more of Ce, La, Gd, Y and Sc, TM is at least one of Ga, Al, Cu, Au, Ag, Zn, In and Mn, 0<x<1, y=12 to 20, z=5.6 to 6.5, w=0 to 8, and v=0 to 2), wherein the average grain size of the crystal grain is 1,000 nm or less, the crystal grain consists of a core and an outer shell, the core has a composition of R1 that is richer than R2, and the outer shell has a composition of R2 that is richer than R1.
    Type: Application
    Filed: August 6, 2019
    Publication date: November 28, 2019
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Masaaki ITO, Masao YANO, Hidefumi KISHIMOTO, Noritsugu SAKUMA, Tetsuya SHOJI, Akira MANABE
  • Patent number: 10468165
    Abstract: To provide a rare earth magnet ensuring excellent magnetic anisotropy while reducing the amount of Nd, etc., and a manufacturing method thereof. A rare earth magnet comprising a crystal grain having an overall composition of (R2(1-x)R1x)yFe100-y-w-z-vCowBzTMv (wherein R2 is at least one of Nd, Pr, Dy and Tb, R1 is an alloy of at least one or two or more of Ce, La, Gd, Y and Sc, TM is at least one of Ga, Al, Cu, Au, Ag, Zn, In and Mn, 0<x<1, y=12 to 20, z=5.6 to 6.5, w=0 to 8, and v=0 to 2), wherein the average grain size of the crystal grain is 1,000 nm or less, the crystal grain consists of a core and an outer shell, the core has a composition of R1 that is richer than R2, and the outer shell has a composition of R2 that is richer than R1.
    Type: Grant
    Filed: June 5, 2014
    Date of Patent: November 5, 2019
    Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Masaaki Ito, Masao Yano, Hidefumi Kishimoto, Noritsugu Sakuma, Tetsuya Shoji, Akira Manabe
  • Patent number: 10464132
    Abstract: A method for producing a raw material powder of a permanent magnet, includes: preparing a material powder of a permanent magnet, measuring magnetic characteristics of the material powder, and judging the quality of the material powder as the raw material powder based on a preliminarily determined relation between magnetic characteristics and the structure of the material powder. A method for producing a permanent magnet includes integrating material powders judged as good in the step of judging the quality as raw material powders by the method for producing a raw material powder of a permanent magnet. A method for inspecting a permanent magnet material powder includes transmitting a magnetic field to a material powder of a permanent magnet, receiving the magnetic field from the material powder, and measuring a magnetic field difference between the transmitted magnetic field and the received magnetic field as magnetic characteristics of the material powder.
    Type: Grant
    Filed: May 24, 2013
    Date of Patent: November 5, 2019
    Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Noritsugu Sakuma, Hidefumi Kishimoto, Mikiya Nozaki, Masao Yano, Tetsuya Shoji, Akira Manabe
  • Publication number: 20190311826
    Abstract: To provide a production method capable of enhancing the magnetic properties, particularly, the coercive force, of a Sm—Fe—N-based rare earth magnet and a production apparatus used therefor. A method for producing a rare earth magnet, comprising mixing a magnetic raw material powder containing Sm, Fe and N with a modifier powder containing metallic Zn to obtain a mixed powder, filling the mixed powder into a molding die to obtain a filled product, melting at least a part of the modifier powder in the filled product while applying a pressure of 20 MPa or less to the filled product or without applying a pressure to obtain an intermediate molded product, and subjecting the intermediate molded product to liquid phase sintering at a pressure of 20 MPa or more to obtain a sintered body; and a production apparatus used therefor.
    Type: Application
    Filed: March 4, 2019
    Publication date: October 10, 2019
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Noritsugu SAKUMA, Kazuaki HAGA
  • Patent number: 10424426
    Abstract: To provide a rare earth magnet ensuring excellent magnetic anisotropy while reducing the amount of Nd, etc., and a manufacturing method thereof. A rare earth magnet comprising a crystal grain having an overall composition of (R2(1-x)R1x)yFe100-y-w-z-vCowBzTMv (wherein R2 is at least one of Nd, Pr, Dy and Tb, R1 is an alloy of at least one or two or more of Ce, La, Gd, Y and Sc, TM is at least one of Ga, Al, Cu, Au, Ag, Zn, In and Mn, 0<x<1, y=12 to 20, z=5.6 to 6.5, w=0 to 8, and v=0 to 2), wherein the average grain size of the crystal grain is 1,000 nm or less, the crystal grain consists of a core and an outer shell, the core has a composition of R1 that is richer than R2, and the outer shell has a composition of R2 that is richer than R1.
    Type: Grant
    Filed: June 5, 2014
    Date of Patent: September 24, 2019
    Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Masaaki Ito, Masao Yano, Hidefumi Kishimoto, Noritsugu Sakuma, Tetsuya Shoji, Akira Manabe
  • Patent number: 10351935
    Abstract: Provided is a magnetic compound represented by the formula (R(1-x)Zrx)a(Fe(1-y)Coy)bTcMdAe (wherein R represents one or more rare earth elements, T represents one or more elements selected from the group consisting of Ti, V, Mo, and W, M represents one or more elements selected from the group consisting of unavoidable impurity elements, Al, Cr, Cu, Ga, Ag, and Au, A represents one or more elements selected from the group consisting of N, C, H, and P, 0?x?0.5, 0?y?0.6, 4?a?20, b=100?a?c?d, 0<c<7, 0?d?1, and 1?e?18), in which a main phase of the magnetic compound includes a ThMn12 type crystal structure, and a volume percentage of an ?-(Fe,Co) phase is 20% or lower.
    Type: Grant
    Filed: September 3, 2015
    Date of Patent: July 16, 2019
    Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Noritsugu Sakuma, Akira Kato, Kota Washio, Hidefumi Kishimoto, Masao Yano, Akira Manabe, Masaaki Ito, Shunji Suzuki, Kurima Kobayashi