Patents by Inventor Masashi OHTSUBO

Masashi OHTSUBO 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: 10535454
    Abstract: Provided is a compressed powder core that can suppress a decrease in the inductance even when a high magnetic field (of greater than or equal to 40 kA/m) is applied to the compressed powder core while suppressing an iron loss and a decrease in the strength of the compressed powder core. The compressed powder core 1A has soft magnetic particles 11A and aluminum nitride layers 12A formed on the surface layers of the respective soft magnetic particles 11A. The compressed powder core 1A has a ratio of the first differential relative permeability ??L to the second differential relative permeability ??H satisfying a relationship of ??L/??H?6, and has a magnetic flux density of greater than or equal to 1.4 T when a magnetic field of 60 kA/m is applied. The soft magnetic particles of the compressed powder core 1A contain Si in the range of 1.0 to 3.
    Type: Grant
    Filed: October 12, 2016
    Date of Patent: January 14, 2020
    Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Daisuke Okamoto, Toshimitsu Takahashi, Sinjiro Saigusa, Kohei Ishii, Naoki Iwata, Jung Hwan Hwang, Masashi Ohtsubo, Takeshi Hattori, Masashi Hara
  • Patent number: 10497500
    Abstract: A powder magnetic core having excellent specific resistance or strength. The powder magnetic core has soft magnetic particles, first coating layers that coat the surfaces of the soft magnetic particles and include aluminum nitride, and second coating layers that coat at least a part of the surfaces of the first coating layers and include a low-melting-point glass having a softening point lower than an annealing temperature for the soft magnetic particles. The first coating layers including aluminum nitride are excellent in the wettability to the low-melting-point glass which constitutes the second coating layers and suppress diffusion of constitutional elements between the soft magnetic particles and the low-melting-point glass of the second coating layers. The powder magnetic core can stably exhibit a higher specific resistance and higher strength than the prior art owing to such a synergistic action of the first coating layers and second coating layers.
    Type: Grant
    Filed: September 4, 2015
    Date of Patent: December 3, 2019
    Assignee: TOYOTA JIDOSHA KABUHIKI KAISHA
    Inventors: Masashi Ohtsubo, Masaaki Tani, Takeshi Hattori, Jung hwan Hwang, Masashi Hara, Shin Tajima, Naoki Iwata, Shinjiro Saigusa, Kohei Ishii, Daisuke Okamoto, Toshimitsu Takahashi
  • Publication number: 20190221340
    Abstract: A method of manufacturing a pressed powder magnetic core disclosed herein may include: mixing soft magnetic metal particles, low-melting-point glass particles and lubricant and heating a mixture of the soft magnetic metal particles, the low-melting-point glass particles and the lubricant at a temperature that is higher than a melting point of the lubricant and is lower than a softening point of the low-melting-point glass particles so as to obtain powder of coated metal particles in which surfaces of the soft magnetic metal particles are coated by the lubricant and the low-melting-point glass particles are distributed in coating layers of the lubricant; filling a mold with the powder; press-molding the powder in the mold; and annealing the press-molded powder. In the pressed powder magnetic core, an amount of the low-melting-point glass particles may be 0.1 wt % to 5.0 wt % relative to an amount of the soft magnetic metal particles.
    Type: Application
    Filed: January 10, 2019
    Publication date: July 18, 2019
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Naoki IWATA, Shinjiro Saigusa, Masafumi Suzuki, Masaaki Nishiyama, Jung Hwan Hwang, Masashi Ohtsubo
  • Publication number: 20190214172
    Abstract: A dust core includes soft magnetic particles, a first coating layer, a second coating layer, and a third coating layer. The first coating layer is made of aluminum oxide with which at least a part of surfaces of the soft magnetic particles are coated. The second coating layer is made of aluminum nitride with which at least a part of a surface of the first coating layer is coated. The third coating layer is made of low-melting-point glass with which at least a part of a surface of the second coating layer is coated. The low-melting-point glass has a softening point lower than an annealing temperature of the soft magnetic particles.
    Type: Application
    Filed: March 18, 2019
    Publication date: July 11, 2019
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Masashi OHTSUBO, Masaaki TANI, Takeshi HATTORI, Junghwan HWANG, Masashi HARA, Shin TAJIMA, Shinjiro SAIGUSA, Kohei ISHII, Daisuke OKAMOTO, Toshimitsu TAKAHASHI
  • Publication number: 20180137959
    Abstract: A dust core includes: a plurality of soft magnetic particles each composed of an iron-based alloy containing aluminum, each of a surface of the plurality of soft magnetic particles being coated with an aluminum nitride film; and an aluminum oxide film with which at least the aluminum nitride films located at a surface of the dust core are entirely coated.
    Type: Application
    Filed: October 26, 2017
    Publication date: May 17, 2018
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Shinjiro SAIGUSA, Naoki IWATA, Masafumi SUZUKI, Masaaki NISHIYAMA, Jung Hwan HWANG, Masashi OHTSUBO
  • Patent number: 9941039
    Abstract: A soft magnetic member is formed such that, when a differential relative permeability in an applied magnetic field of 100 A/m is represented by a first differential relative permeability ??L, and when a differential relative permeability in an applied magnetic field of 40 kA/m is represented by a second differential relative permeability ??H, a ratio of the first differential relative permeability ??L to the second differential relative permeability ??H satisfies a relationship of ??L/??H?10, and a magnetic flux density in an applied magnetic field of 60 kA/m is 1.15 T or higher.
    Type: Grant
    Filed: June 12, 2015
    Date of Patent: April 10, 2018
    Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Daisuke Okamoto, Kiyotaka Onodera, Shinjiro Saigusa, Kohei Ishii, Masashi Ohtsubo, Junghwan Hwang, Masaaki Tani, Takeshi Hattori
  • Publication number: 20170263359
    Abstract: A powder magnetic core having excellent specific resistance or strength. The powder magnetic core has soft magnetic particles, first coating layers that coat the surfaces of the soft magnetic particles and include aluminum nitride, and second coating layers that coat at least a part of the surfaces of the first coating layers and include a low-melting-point glass having a softening point lower than an annealing temperature for the soft magnetic particles. The first coating layers including aluminum nitride are excellent in the wettability to the low-melting-point glass which constitutes the second coating layers and suppress diffusion of constitutional elements between the soft magnetic particles and the low-melting-point glass of the second coating layers. The powder magnetic core can stably exhibit a higher specific resistance and higher strength than the prior art owing to such a synergistic action of the first coating layers and second coating layers.
    Type: Application
    Filed: September 4, 2015
    Publication date: September 14, 2017
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Masashi OHTSUBO, Masaaki TANI, Takeshi HATTORI, Jung hwan HWANG, Masashi HARA, Shin TAJIMA, Naoki IWATA, Shinjiro SAIGUSA, Kohei ISHII, Daisuke OKAMOTO, Toshimitsu TAKAHASHI
  • Publication number: 20170110227
    Abstract: Provided is a compressed powder core that can suppress a decrease in the inductance even when a high magnetic field (of greater than or equal to 40 kA/m) is applied to the compressed powder core while suppressing an iron loss and a decrease in the strength of the compressed powder core. The compressed powder core 1A has soft magnetic particles 11A and aluminum nitride layers 12A formed on the surface layers of the respective soft magnetic particles 11A. The compressed powder core 1A has a ratio of the first differential relative permeability ??L to the second differential relative permeability ??H satisfying a relationship of ??L/??H?6, and has a magnetic flux density of greater than or equal to 1.4 T when a magnetic field of 60 kA/m is applied. The soft magnetic particles of the compressed powder core 1A contain Si in the range of 1.0 to 3.
    Type: Application
    Filed: October 12, 2016
    Publication date: April 20, 2017
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Daisuke OKAMOTO, Toshimitsu TAKAHASHI, Sinjiro SAIGUSA, Kohei ISHII, Naoki IWATA, Jung Hwan HWANG, Masashi OHTSUBO, Takeshi HATTORI, Masashi HARA
  • Publication number: 20160071636
    Abstract: A dust core includes soft magnetic particles, a first coating layer, a second coating layer, and a third coating layer. The first coating layer is made of aluminum oxide with which at least a part of surfaces of the soft magnetic particles are coated. The second coating layer is made of aluminum nitride with which at least a part of a surface of the first coating layer is coated. The third coating layer is made of low-melting-point glass with which at least a part of a surface of the second coating layer is coated. The low-melting-point glass has a softening point lower than an annealing temperature of the soft magnetic particles.
    Type: Application
    Filed: September 8, 2015
    Publication date: March 10, 2016
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Masashi OHTSUBO, Masaaki Tani, Takeshi Hattori, Junghwan Hwang, Masashi Hara, Shin Tajima, Shinjiro Saigusa, Kohei Ishii, Daisuke Okamoto, Toshimitsu Takahashi
  • Publication number: 20150364235
    Abstract: A soft magnetic member is formed such that, when a differential relative permeability in an applied magnetic field of 100 A/m is represented by a first differential relative permeability ??L, and when a differential relative permeability in an applied magnetic field of 40 kA/m is represented by a second differential relative permeability ??H, a ratio of the first differential relative permeability ??L to the second differential relative permeability ??H satisfies a relationship of ??L/??H?10, and a magnetic flux density in an applied magnetic field of 60 kA/m is 1.15 T or higher.
    Type: Application
    Filed: June 12, 2015
    Publication date: December 17, 2015
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Daisuke OKAMOTO, Kiyotaka ONODERA, Shinjiro SAIGUSA, Kohei ISHII, Masashi OHTSUBO, Junghwan HWANG, Masaaki TANI, Takeshi HATTORI