Patents by Inventor Isao Nakahata

Isao Nakahata 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: 11955261
    Abstract: A specific depth at which a concentration of Fe reaches 10 at % is 18 nm or more and 500 nm or less from the first surface, and from the first surface to the specific depth, the concentration of Fe is less than 10 at %, and a positive increase region is present in which the concentration of Fe increases with a substantially positive concentration gradient, in a case where the concentration of Fe is measured in a depth direction from a first surface of a ribbon.
    Type: Grant
    Filed: August 23, 2022
    Date of Patent: April 9, 2024
    Assignee: TDK CORPORATION
    Inventors: Kyotaro Abe, Isao Nakahata, Takuya Tsukahara
  • Publication number: 20240079165
    Abstract: A soft magnetic powder including a first particle group including particles having a particle size of D50 or more and a second particle group including particles having a particle size of less than D50. An average value of circularities of the particles belonging to the first particle group is defined as a first average circularity C1, and an average value of circularities of the particles belonging to the second particle group is defined as a second average circularity C2, and C1<C2 is satisfied.
    Type: Application
    Filed: August 29, 2023
    Publication date: March 7, 2024
    Applicant: TDK CORPORATION
    Inventors: Yuta NAKAGAWA, Kazuhiro YOSHIDOME, Isao NAKAHATA
  • Publication number: 20230368959
    Abstract: A magnetic core includes a first core and a second core. The first core includes a first opposing surface. The second core includes a second opposing surface. The first opposing surface and the second opposing surface are aligned so as to form at least a part of a closed magnetic circuit consisting of the first core and the second core. The first opposing surface and/or the second opposing surface has an arithmetic mean roughness Ra of 7 ?m or more and less than 65 ?m.
    Type: Application
    Filed: May 11, 2023
    Publication date: November 16, 2023
    Applicant: TDK CORPORATION
    Inventors: Kyotaro ABE, Isao NAKAHATA
  • Publication number: 20230085009
    Abstract: A specific depth at which a concentration of Fe reaches 10 at % is 18 nm or more and 500 nm or less from the first surface, and from the first surface to the specific depth, the concentration of Fe is less than 10 at %, and a positive increase region is present in which the concentration of Fe increases with a substantially positive concentration gradient, in a case where the concentration of Fe is measured in a depth direction from a first surface of a ribbon.
    Type: Application
    Filed: August 23, 2022
    Publication date: March 16, 2023
    Applicant: TDK CORPORATION
    Inventors: Kyotaro ABE, Isao NAKAHATA, Takuya TSUKAHARA
  • Publication number: 20230079841
    Abstract: Provided a soft magnetic alloy ribbon containing Fe and B. Convex portions having an average convex portion height of 7 nm to 130 nm are present on an alloy surface.
    Type: Application
    Filed: August 23, 2022
    Publication date: March 16, 2023
    Applicant: TDK CORPORATION
    Inventors: Kyotaro ABE, Isao NAKAHATA, Takuya TSUKAHARA
  • Publication number: 20220328224
    Abstract: To provide a soft magnetic alloy or the like, from which a magnetic component having a good temperature property of core loss can be obtained. The soft magnetic alloy includes Fe. The soft magnetic alloy includes a crystallite, and an amorphous phase existing around the crystallite. A total area ratio of the crystallite in a cross section of the soft magnetic alloy is 40% or more and less than 60%. An average thickness of the amorphous phase is 3.0 nm or more and 10.0 nm or less. A standard deviation of a thickness of the amorphous phase is 10.0 nm or less.
    Type: Application
    Filed: March 24, 2022
    Publication date: October 13, 2022
    Applicant: TDK CORPORATION
    Inventors: Takuya TSUKAHARA, Isao NAKAHATA, Kazuhiro YOSHIDOME
  • Patent number: 11441213
    Abstract: A soft magnetic alloy ribbon having high corrosion resistance and good magnetic properties is obtained. The soft magnetic alloy ribbon contains Fe and M. M is at least one selected from the group consisting of Nb, Ta, W, Zr, Hf, Mo, Cr, and Ti, and a part of M is included in oxides. A maximum point of a concentration of at least one of M included in the oxides is present in a region within 20 nm from the surface, when a concentration distribution of an element contained in the soft magnetic alloy ribbon is measured from a surface toward an interior of the soft magnetic alloy ribbon in a thickness direction.
    Type: Grant
    Filed: November 19, 2020
    Date of Patent: September 13, 2022
    Assignee: TDK CORPORATION
    Inventors: Takuya Tsukahara, Isao Nakahata, Kazuhiro Yoshidome, Hiroyuki Matsumoto
  • Patent number: 11427896
    Abstract: A soft magnetic alloy thin strip which has high saturation magnetic flux density and low coercivity, which enables a core with high space factor and high saturation magnetic flux density. A soft magnetic alloy thin strip including a main component that has a composition formula (Fe(1?(?+?))X1?X2?)(1?(a+b+c+d+e+f))MaBbPcSidCeSf. In the formula, X1, X2 and M are selected from a specific element group; 0?a?0.140, 0.020?b?0.200, 0?c?0.150, 0?d?0.090, 0?e?0.030, 0?f?0.030, ??0, ??0, and 0??+??0.50; and at least one of a, c and d is larger than 0. The strip has a structure that is composed of an Fe-based nanocrystal; and the surface roughness of a release surface satisfies 0.85?Rae/Rac?1.25 (wherein Rac is the average of arithmetic mean roughnesses in the central portion, and Rae is the average in the edge portion).
    Type: Grant
    Filed: December 3, 2018
    Date of Patent: August 30, 2022
    Assignee: TDK CORPORATION
    Inventors: Akito Hasegawa, Hironobu Kumaoka, Kazuhiro Yoshidome, Hiroyuki Matsumoto, Kenji Horino, Isao Nakahata
  • Patent number: 11145448
    Abstract: A soft magnetic alloy powder includes a plurality of soft magnetic alloy particles of a soft magnetic alloy represented by a composition formula (Fe(1?(?+?))X1?X2?)(1?(a+b+c+d+e))MaBbPcSidCe, wherein X1 represents Co and/or Ni; X2 represents at least one selected from the group consisting of Al, Mn, Ag, Zn, Sn, As, Sb, Cu, Cr, Bi, N, O, and rare earth elements; M represents at least one selected from the group consisting of Nb, Hf, Zr, Ta, Mo, W, and V; 0.020?a?0.14, 0.020<b?0.20, 0<c?0.15, 0?d?0.060, 0?e?0.040, ??0, ??0, and 0??+??0.50 are satisfied, and wherein the soft magnetic alloy has a nano-heterostructure with initial fine crystals present in an amorphous substance; and the surface of each of the soft magnetic alloy particles is covered with a coating portion including a compound of at least one element selected from the group consisting of P, Si, Bi, and Zn.
    Type: Grant
    Filed: March 8, 2019
    Date of Patent: October 12, 2021
    Assignee: TDK CORPORATION
    Inventors: Masakazu Hosono, Kenji Horino, Hiroyuki Matsumoto, Kazuhiro Yoshidome, Akito Hasegawa, Hajime Amano, Isao Nakahata
  • Publication number: 20210301380
    Abstract: An alloy ribbon that is an alloy ribbon containing a metal as a main component, and has a recess on at least one principal surface, in which a depth of the recess is 5% or more and 75% or less of an average thickness.
    Type: Application
    Filed: March 25, 2021
    Publication date: September 30, 2021
    Applicant: TDK CORPORATION
    Inventors: Isao NAKAHATA, Takuya TSUKAHARA
  • Publication number: 20210304936
    Abstract: The object of the present invention is to provide an alloy ribbon capable of having excellent adhesiveness between the alloy ribbons when a plurality of the alloy ribbons is stacked; and also, to provide a magnetic core using the alloy ribbon. The present invention is an alloy ribbon comprising metals scattered on at least one surface of the alloy ribbon, in which diameters of the scattered metals are 1 ?m or more, and the scattered metals include Cu.
    Type: Application
    Filed: March 23, 2021
    Publication date: September 30, 2021
    Applicant: TDK CORPORATION
    Inventors: Kyotaro ABE, Takuya TSUKAHARA, Isao NAKAHATA, Kazuhiro YOSHIDOME
  • Patent number: 11081266
    Abstract: Soft magnetic alloy powder includes plurality of soft magnetic alloy particles of soft magnetic alloy represented by composition formula (Fe(1?(?+?))X1?X2?)(1?(a+b+c++e+f+g))MaBbPcSidCeSfTig, wherein X1 represents Co and/or Ni; X2 represents at least one selected from group consisting of Al, Mn, Ag, Zn, Sn, As, Sb, Cu, Cr, Bi, N, O, and rare earth elements; M represents at least one selected from group consisting of Nb, Hf, Zr, Ta, Mo, W, and V; 0.020?a?0.14, 0.020<b?0.20, 0<c?0.15, 0?d?0.060, 0?e?0.040, 0?f?0.010, 0?g?0.0010, ??0, ??0, and 0??+??0.50 are satisfied, wherein at least one of f and g is more than 0; and wherein soft magnetic alloy has a nano-heterostructure with initial fine crystals present in an amorphous substance; and surface of each of the soft magnetic alloy particles is covered with a coating portion including a compound of at least one element selected from group consisting of P, Si, Bi, and Zn.
    Type: Grant
    Filed: March 8, 2019
    Date of Patent: August 3, 2021
    Assignee: TDK CORPORATION
    Inventors: Masakazu Hosono, Hiroyuki Matsumoto, Kenji Horino, Kazuhiro Yoshidome, Isao Nakahata, Akito Hasegawa, Hajime Amano
  • Publication number: 20210156011
    Abstract: A soft magnetic alloy ribbon having high corrosion resistance and good magnetic properties is obtained. The soft magnetic alloy ribbon contains Fe and M. M is at least one selected from the group consisting of Nb, Ta, W, Zr, Hf, Mo, Cr, and Ti, and a part of M is included in oxides. A maximum point of a concentration of at least one of M included in the oxides is present in a region within 20 nm from the surface, when a concentration distribution of an element contained in the soft magnetic alloy ribbon is measured from a surface toward an interior of the soft magnetic alloy ribbon in a thickness direction.
    Type: Application
    Filed: November 19, 2020
    Publication date: May 27, 2021
    Applicant: TDK CORPORATION
    Inventors: Takuya TSUKAHARA, Isao NAKAHATA, Kazuhiro YOSHIDOME, Hiroyuki MATSUMOTO
  • Publication number: 20210159001
    Abstract: A soft magnetic alloy ribbon having high corrosion resistance is obtained. The soft magnetic alloy ribbon contains Fe, P, and Si. A maximum point of a concentration of P and a maximum point of a concentration of Si including in oxides is present in a region within 20 nm from the surface, when a concentration distribution of an element contained in the soft magnetic alloy ribbon is measured from a surface toward an interior of the soft magnetic alloy ribbon in a thickness direction.
    Type: Application
    Filed: November 19, 2020
    Publication date: May 27, 2021
    Applicant: TDK CORPORATION
    Inventors: Takuya TSUKAHARA, Isao NAKAHATA, Kazuhiro YOSHIDOME, Hiroyuki MATSUMOTO
  • Publication number: 20210035726
    Abstract: A magnetic core excellent in productivity, having stable magnetic characteristics, and easy to handle for a coil device including a conductor and is formed by stacking a plurality of soft magnetic thin ribbons divided into small pieces.
    Type: Application
    Filed: March 1, 2019
    Publication date: February 4, 2021
    Applicant: TDK CORPORATION
    Inventors: Isao NAKAHATA, Hiroyuki MATSUMOTO, Osamu HIROSE
  • Publication number: 20210005364
    Abstract: A magnetic core and the like having a stable soft magnetic property, including a plurality of soft magnetic layers which are laminated, wherein a crack is formed in the soft magnetic layers. The soft magnetic layers include Fe as a principal component. The soft magnetic layers include a composition formula (Fe(1?(?+?))X1?X2?)(1?(a+b+c+d+e+f))MaBbPcSidCeSf, wherein: X1 is one or more selected from the group consisting of Co and Ni, X2 is one or more selected from the group consisting of Al, Mn, Ag, Zn, Sn, As, Sb, Cu, Cr, Bi, N, and O and rare-earth elements, M is one or more selected from the group consisting of Nb, Hf, Zr, Ta, Mo, V, and W; and a to f and ? and ? are in predetermined ranges. A structure including a nanoheterostructure or an Fe-group nanocrystal is observed in the soft magnetic layers.
    Type: Application
    Filed: March 1, 2019
    Publication date: January 7, 2021
    Applicant: TDK CORPORATION
    Inventors: Isao NAKAHATA, Kazuhiro YOSHIDOME, Hiroyuki MATSUMOTO, Akito HASEGAWA
  • Patent number: 10847292
    Abstract: A soft magnetic alloy is composed of a Fe-based nanocrystal and an amorphous phase. In the soft magnetic alloy, S2-S1>0 is satisfied, where S1 (at %) denotes an average content rate of Si in the Fe-based nanocrystal and S2 (at %) denotes an average content rate of Si in the amorphous phase. In addition, the soft magnetic alloy has a composition formula of ((Fe(1?(?+?))X1?X2?)(1?(a+b+c+d+e+f))MaBbSicPdCreCuf)1?gCg. X1 is one or more selected from the group consisting of Co and Ni, X2 is one or more selected from the group consisting of Al, Mn, Ag, Zn, Sn, As, Sb, Bi, N, O, S and a rare earth element, and M is one or more selected from the group consisting of Nb, Hf, Zr, Ta, Ti, Mo, V and W. In the composition formula, a to g, ? and ? are in specific ranges.
    Type: Grant
    Filed: August 6, 2018
    Date of Patent: November 24, 2020
    Assignee: TDK CORPORATION
    Inventors: Kazuhiro Yoshidome, Akito Hasegawa, Hiroyuki Matsumoto, Kenji Horino, Akihiro Harada, Syota Goto, Isao Nakahata
  • Publication number: 20200362442
    Abstract: A soft magnetic alloy thin strip which has high saturation magnetic flux density and low coercivity, which enables a core with high space factor and high saturation magnetic flux density. A soft magnetic alloy thin strip including a main component that has a composition formula (Fe(1?(?+?))X1?X2?)(1?(a+b+c+d+e+f))MaBbPcSidCeSf. In the formula, X1, X2 and M are selected from a specific element group; 0?a?0.140, 0.020?b?0.200, 0?c?0.150, 0?d?0.090, 0?e?0.030, 0?f?0.030, ??0, ??0, and 0??+??0.50; and at least one of a, c and d is larger than 0. The strip has a structure that is composed of an Fe-based nanocrystal; and the surface roughness of a release surface satisfies 0.85?Rae/Rac?1.25 (wherein Rac is the average of arithmetic mean roughnesses in the central portion, and Rae is the average in the edge portion).
    Type: Application
    Filed: December 3, 2018
    Publication date: November 19, 2020
    Applicant: TDK CORPORATION
    Inventors: Akito HASEGAWA, Hironobu KUMAOKA, Kazuhiro YOSHIDOME, Hiroyuki MATSUMOTO, Kenji HORINO, Isao NAKAHATA
  • Publication number: 20190279799
    Abstract: A soft magnetic alloy powder includes a plurality of soft magnetic alloy particles of a soft magnetic alloy represented by a composition formula (Fe(1?(?+?))X1?X2?)(1?(a+b+c+d+e))MaBbPcSidCe, wherein X represents Co and/or Ni; X2 represents at least one selected from the group consisting of Al, Mn, Ag, Zn, Sn, As, Sb, Cu, Cr, Bi, N, O, and rare earth elements; M represents at least one selected from the group consisting of Nb, Hf, Zr, Zr, Ta, Mo, W, and V; 0.020?a?0.14, 0.020<b?0.20, 0<c?0.15, 0?d?0.060, 0?e?0.040, ??0, ??0, and 0??+??0.50 are satisfied, and wherein the soft magnetic alloy has a nano-heterostructure with initial fine crystals present in an amorphous substance; and the surface of each of the soft magnetic alloy particles is covered with a coating portion including a compound of at least one element selected from the group consisting of P, Si, Bi, and Zn.
    Type: Application
    Filed: March 8, 2019
    Publication date: September 12, 2019
    Applicant: TDK CORPORATION
    Inventors: Masakazu HOSONO, Kenji HORINO, Hiroyuki MATSUMOTO, Kazuhiro YOSHIDOME, Akito HASEGAWA, Hajime AMANO, Isao NAKAHATA
  • Publication number: 20190279796
    Abstract: Soft magnetic alloy powder includes plurality of soft magnetic alloy particles of soft magnetic alloy represented by composition formula (Fe(1?(?+?))X1?X2?)(1?(a+b+c++e+f+g))MaBbPcSidCeSfTig, wherein X1 represents Co and/or Ni; X2 represents at least one selected from group consisting of Al, Mn, Ag, Zn, Sn, As, Sb, Cu, Cr, Bi, N, O, and rare earth elements; M represents at least one selected from group consisting of Nb, Hf, Zr, Ta, Mo, W, and V; 0.020?a?0.14, 0.020<b?0.20, 0<c?0.15, 0?d?0.060, 0?e?0.040, 0?f?0.010, 0?g?0.0010, ??0, ??0, and 0??+??0.50 are satisfied, wherein at least one of f and g is more than 0; and wherein soft magnetic alloy has a nano-heterostructure with initial fine crystals present in an amorphous substance; and surface of each of the soft magnetic alloy particles is covered with a coating portion including a compound of at least one element selected from group consisting of P, Si, Bi, and Zn.
    Type: Application
    Filed: March 8, 2019
    Publication date: September 12, 2019
    Applicant: TDK CORPORATION
    Inventors: Masakazu HOSONO, Hiroyuki MATSUMOTO, Kenji HORINO, Kazuhiro YOSHIDOME, Isao NAKAHATA, Akito HASEGAWA, Hajime AMANO