Patents by Inventor Takahito MIZUMURA

Takahito MIZUMURA 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: 20240170196
    Abstract: When joining end faces of a plurality of soft magnetic sheets which are superposed in the sheet thickness direction and which are bent at parts forming corner areas of a core, offset of positions of the end faces from the desired positions is suppressed. In a region of a window part comprised of a region inside of a first part 110 and second part 120, a third part 130 with a length in a longitudinal direction (X-axial direction) the same as a length in the X-axial direction of the window part at the position where the third part 130 is arranged is arranged so as to contact the region of the inner circumferential surface between the first corner area 101 and third corner area 103.
    Type: Application
    Filed: November 28, 2023
    Publication date: May 23, 2024
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Takahito MIZUMURA, Masato MIZOKAMI, Fumiaki TAKAHASHI, Hisashi MOGI
  • Publication number: 20240096540
    Abstract: This wound core is a wound core including a wound core main body obtained by stacking a plurality of polygonal annular grain-oriented electrical steel sheets in a side view, and the grain-oriented electrical steel sheet has planar portions and bent portions that are alternately continuous in a longitudinal direction, and in at least one bent portion, the crystal grain size Dpx (mm) of the grain-oriented electrical steel sheet is FL/4 or more. Here, FL the an average length (mm) of the planar portions.
    Type: Application
    Filed: October 26, 2021
    Publication date: March 21, 2024
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Yusuke KAWAMURA, Takahito MIZUMURA
  • Patent number: 11869697
    Abstract: When joining end faces of a plurality of soft magnetic sheets which are superposed in the sheet thickness direction and which are bent at parts forming corner areas of a core, offset of positions of the end faces from the desired positions is suppressed. In a region of a window part comprised of a region inside of a first part 110 and second part 120, a third part 130 with a length in a longitudinal direction (X-axial direction) the same as a length in the X-axial direction of the window part at the position where the third part 130 is arranged is arranged so as to contact the region of the inner circumferential surface between the first corner area 101 and third corner area 103.
    Type: Grant
    Filed: October 2, 2019
    Date of Patent: January 9, 2024
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Takahito Mizumura, Masato Mizokami, Fumiaki Takahashi, Hisashi Mogi
  • Publication number: 20230402221
    Abstract: A wound core (10) is a wound core including a portion in which grain-oriented electrical steel sheets (1) in which planar portions (4) and bent portions (5) are alternately continuous in a longitudinal direction are stacked in a sheet thickness direction and formed by stacking the grain-oriented electrical steel sheets (1) that have been individually bent in layers and assembled into a wound shape, wherein, when an average length of a roughness curve element in a width direction intersecting the longitudinal direction forming a surface of the bent portion (5) of the grain-oriented electrical steel sheet (1) is RSm(b), and an average length of the roughness curve element in the width direction forming a surface of the planar portion 4 of the grain-oriented electrical steel sheet (1) is RSm(s), the relationship of 1.00<RSm(b)/RSm(s)?5.00 is satisfied.
    Type: Application
    Filed: October 26, 2021
    Publication date: December 14, 2023
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Masataka IWAKI, Takahito MIZUMURA, Hisashi MOGI
  • Publication number: 20230395319
    Abstract: A wound core (10) in which, in a laminating direction, when the surface roughness of a steel sheet portion in a direction connecting a center in a sheet thickness direction of a grain-oriented electrical steel sheet (1) positioned on the innermost periphery of the wound core among the laminated grain-oriented electrical steel sheets (1) and a center in the sheet thickness direction of the grain-oriented electrical steel sheet (1) positioned on the outermost periphery of the wound core (10) is Ral, and the surface roughness of the grain-oriented electrical steel sheet (1) in a direction parallel to a longitudinal direction on an end surface of a planar portion (4) of the laminated grain-oriented electrical steel sheet (1) is Rac, a ratio Ral/Rac between Rat and Rac satisfies the relationship of 1.5?Ral/Rac?12.0.
    Type: Application
    Filed: October 26, 2021
    Publication date: December 7, 2023
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Takahito MIZUMURA, Hisashi MOGI, Masato MIZOKAMI, Masaru TAKAHASHI
  • Publication number: 20230395293
    Abstract: Provided is a wound core including: a substantially rectangular wound core main body in a side view, in which the wound core main body includes a portion in which grain-oriented electrical steel sheets in which planar portions and corner portions are alternately continuous in a longitudinal direction and an angle formed by two planar portions adjacent to each other with each of the corner portions therebetween is 90° are stacked in a sheet thickness direction and has a substantially rectangular laminated structure in a side view, each of the corner portions has two or more bent portions having a curved shape in a side view of the grain-oriented electrical steel sheets 1, the sum of bent angles of the bent portions present in one corner portion is 90°, each bent portion in a side view has an inner side radius of curvature r of 1 mm to 5 mm, and interlaminar friction coefficients which are dynamic friction coefficients of the laminated grain-oriented electrical steel sheets in at least some of the planar portio
    Type: Application
    Filed: October 26, 2021
    Publication date: December 7, 2023
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Yusuke KAWAMURA, Takahito MIZUMURA
  • Publication number: 20230395300
    Abstract: This wound core is a wound core including a wound core main body obtained by laminating a plurality of polygonal annular grain-oriented electrical steel sheets in a side view, and the grain-oriented electrical steel sheet has planar portions and bent portions that are alternately continuous in a longitudinal direction, and in at least one bent portion, the crystal grain size Dpx of the grain-oriented electrical steel sheet is 2 W or less.
    Type: Application
    Filed: October 26, 2021
    Publication date: December 7, 2023
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Yusuke KAWAMURA, Takahito MIZUMURA
  • Publication number: 20230395302
    Abstract: This wound core is a wound core including a wound core main body obtained by stacking a plurality of polygonal annular grain-oriented electrical steel sheets in a side view, and the grain-oriented electrical steel sheet has planar portions and bent portions that are alternately continuous in a longitudinal direction, and in a planar portion in the vicinity of at least one bent portion, when the three-dimensional crystal orientation difference between two adjacent points in a series of points arranged at equal intervals in the extension direction of the bent portion is ?, a total number of measured data items of ? is Nx, the number of data items that satisfy ??1.0° is Nt, the number of data items that satisfy ? of 1.0° or more and less than 2.5° is Na, the number of data items that satisfy ? of 2.5° or more and less than 4.0° is Nb, and the number of data items that satisfy ? of 4.0° or more is Nc, the following formulae (1) to (4) are satisfied: 0.10?Nt/Nx?0.80??(1) 0.37?Nb/Nt?0.80??(2) 1.07?Nb/Na?4.
    Type: Application
    Filed: October 26, 2021
    Publication date: December 7, 2023
    Applicant: NIPPON STEEL CORPORATION
    Inventor: Takahito MIZUMURA
  • Publication number: 20230386740
    Abstract: In this method of producing a wound core, at least one bent portion (5) of one or more laminated grain oriented electrical steel sheets (1) is formed such that one side (1b) of the steel sheet (1) is placed and constrained on a die (30) and a punch (40) is press formed against a portion (1a) of the steel sheet (1) to be bent on the other free end side in the thickness (T) direction of the steel sheet. Outer surfaces of the die and the punch each have an arc portion (30a, 40a) having a predetermined curvature, and when the thickness of the steel sheet (1) is T, bent angles of the bent portions (5) are ?(°), a radius of curvature of the arc portion (30a) of the die is Rd, and a radius of curvature of the arc portion (40a) of the punch is Rp, relationships of Equations (1) to (5) below are satisfied. 0.02?T/(2Rd+T)?0.15 ??(1) 0.5 ?Rd ?3.0 ??(2) 0.15 ?T ?0.30 ??(3) 2.
    Type: Application
    Filed: October 26, 2021
    Publication date: November 30, 2023
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Masaru TAKAHASHI, Takahito MIZUMURA
  • Publication number: 20230298800
    Abstract: This wound core (10) is a wound core (10) including a portion in which grain-oriented electrical steel sheets (1) in which planar'portions (4) and bent portions (5) are alternately continuous in a longitudinal direction are stacked in a sheet thickness direction and formed by stacking the grain-oriented electrical steel sheets (1) that have been individually bent in layers and assembled into a wound shape, wherein, when an average height of a roughness curve element in a width direction intersecting the longitudinal direction forming a surface of the bent portion (5) of the grain-oriented electrical steel sheet (1) is Ra(b) and an average height of a roughness curve element in a width direction forming ,a surface of the planar portion (4) of the grain-oriented electrical steel sheet (1) is Ra(s), the relationship of 1.00<Ra(b)/Ra(s)?5.00 is satisfied.
    Type: Application
    Filed: October 26, 2021
    Publication date: September 21, 2023
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Masataka IWAKI, Takahito MIZUMURA, Hisashi MOGI
  • Publication number: 20230290569
    Abstract: A wound core (10) is a wound core having a wound shape (10) including a rectangular hollow portion (15) in a center and a portion in which grain-oriented electrical steel sheets (1) in which planar portions (4) and bent portions (5) are alternately continuous in a longitudinal direction are stacked in a sheet thickness direction, which is a wound core formed by stacking the grain-oriented electrical steel sheets(1) that have been individually bent in layers and assembled into a wound shape and in which the plurality of grain-oriented electrical steel sheets are connected to each other via at least one joining part (6) for each roll, wherein the bent portion (5) of the laminated grain-oriented electrical steel sheet (1) has an average Vickers hardness of 190 to 250 HV in an L cross section in the longitudinal direction which is a cross section of the grain-oriented electrical steel sheet (1) in a thickness direction.
    Type: Application
    Filed: October 26, 2021
    Publication date: September 14, 2023
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Takahito MIZUMURA, Hisashi MOGI, Masato MIZOKAMI, Masaru TAKAHASHI
  • Patent number: 11742140
    Abstract: Provided is a wound core formed by laminating a plurality of bent bodies obtained by forming a coated grain-oriented electrical steel sheet in which a coating is formed on at least one surface of a grain-oriented electrical steel sheet so that the coating is on an outside, in a sheet thickness direction, in which the bent body has a bent region obtained by bending the coated grain-oriented electrical steel sheet and a flat region adjacent to the bent region, the number of deformation twins present in the bent region in a side view is five or less per 1 mm of a length of a center line in the sheet thickness direction in the bent region, and when a region extending 40 times a sheet thickness to both sides in a circumferential direction from a center of the bent region on an outer circumferential surface of the bent body is defined as a strain affected region, a proportion of an area where the coating is not damaged at any position along the circumferential direction in a flat region within the strain affected r
    Type: Grant
    Filed: April 27, 2020
    Date of Patent: August 29, 2023
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Takahito Mizumura, Masato Mizokami, Hisashi Mogi, Fumiaki Takahashi
  • Publication number: 20220351890
    Abstract: A wound core equipped with a laminated body including plural electrical steel sheets stacked in a ring shape in side view. The laminated body includes plural bent portions, and plural block-shaped portions at positions between adjacent bent portions. At least one block-shaped portion among the plural block-shaped portions includes a heat transmission path bordered by the electrical steel sheets at least at a portion between the stacked electrical steel sheets. The heat transmission path is included only at the at least one block-shaped portion.
    Type: Application
    Filed: September 3, 2020
    Publication date: November 3, 2022
    Inventors: Hisashi MOGI, Takahito MIZUMURA, Teruyuki TAMAKI, Hiroshi FUJIMURA, Ryu HIRAYAMA
  • Publication number: 20220285074
    Abstract: A wound core equipped with a laminated body including plural electrical steel sheets stacked in a ring shape in side view. The laminated body includes plural bent portions, and plural block-shaped portions at positions between adjacent bent portions. At least one bent portion among the plural bent portions is a high stacking factor bent portion, wherein a stacking factor of the electrical steel sheets at the high stacking bent portion is higher than an average stacking factor of the steel sheets at the plural block-shaped portions.
    Type: Application
    Filed: September 3, 2020
    Publication date: September 8, 2022
    Inventors: Hisashi MOGI, Takahito MIZUMURA, Teruyuki TAMAKI, Hiroshi FUJIMURA, Ryu HIRAYAMA
  • Publication number: 20220199320
    Abstract: Provided is a wound core formed by laminating a plurality of bent bodies obtained by forming a coated grain-oriented electrical steel sheet in which a coating is formed on at least one surface of a grain-oriented electrical steel sheet so that the coating is on an outside, in a sheet thickness direction, in which the bent body has a bent region obtained by bending the coated grain-oriented electrical steel sheet and a flat region adjacent to the bent region, the number of deformation twins present in the bent region in a side view is five or less per 1 mm of a length of a center line in the sheet thickness direction in the bent region, and when a region extending 40 times a sheet thickness to both sides in a circumferential direction from a center of the bent region on an outer circumferential surface of the bent body is defined as a strain affected region, a proportion of an area where the coating is not damaged at any position along the circumferential direction in a flat region within the strain affected r
    Type: Application
    Filed: April 27, 2020
    Publication date: June 23, 2022
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Takahito MIZUMURA, Masato MIZOKAMI, Hisashi MOGI, Fumiaki TAKAHASHI
  • Publication number: 20210327631
    Abstract: The present invention provides a magnetic core and transformer which are reduced in core loss. The magnetic core according to the present invention comprises a core member which is formed by winding first electrical steel sheets, which is ring shaped seen from a side surface, and which has one or more bent parts seen from a side surface and one or more stacks of second electrical steel sheets stacked together, each the stack being arranged at least at one of the surfaces formed by side surfaces of the first electrical steel sheets at a bent part of the core member so that a surface formed by side surfaces of the second electrical steel sheets runs along it.
    Type: Application
    Filed: October 3, 2019
    Publication date: October 21, 2021
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Hisashi MOGI, Takahito MIZUMURA, Fumiaki TAKAHASHI, Teruyuki TAMAKI
  • Publication number: 20210319943
    Abstract: When joining end faces of a plurality of soft magnetic sheets which are superposed in the sheet thickness direction and which are bent at parts forming corner areas of a core, offset of positions of the end faces from the desired positions is suppressed. In a region of a window part comprised of a region inside of a first part 110 and second part 120, a third part 130 with a length in a longitudinal direction (X-axial direction) the same as a length in the X-axial direction of the window part at the position where the third part 130 is arranged is arranged so as to contact the region of the inner circumferential surface between the first corner area 101 and third corner area 103.
    Type: Application
    Filed: October 2, 2019
    Publication date: October 14, 2021
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Takahito MIZUMURA, Masato MIZOKAMI, Fumiaki TAKAHASHI, Hisashi MOGI
  • Patent number: 10886055
    Abstract: A wound core is formed by laminating a plurality of bent bodies formed from a grain-oriented electrical steel sheet having a coating containing phosphorus formed on a surface, in a sheet thickness direction of the grain-oriented electrical steel sheet, in which the bent body is formed in a rectangular shape by having four flat portions and four corner portions adjacent to the flat portions, the corner portion has a bent region having a total bending angle of approximately 90° in a side view, the number of deformation twins present in the bent region in the side view is five or less per 1 mm of a length of a center line in the bent region in the sheet thickness direction, and the amount of phosphorus eluted from the corner portion in a case of being boiled in water for 30 minutes is 6.0 mg or less per 1 m2 of a surface area of the corner portion.
    Type: Grant
    Filed: January 10, 2018
    Date of Patent: January 5, 2021
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Takahito Mizumura, Masato Mizokami, Masao Yabumoto, Toshihiko Uemura, Eisuke Minematsu, Fumiaki Takahashi
  • Patent number: 10662491
    Abstract: A grain-oriented electrical steel sheet comprising a steel sheet having a surface on which grooves, in which an extending direction crosses a rolling direction and a depth direction is parallel to a sheet thickness direction, are formed, and wherein a molten solidified substance ranging in parallel to the groove exists on both sides of the groove on the surface of the steel sheet, and a height becoming a maximum frequency in a height distribution of height data in which the surface of the steel sheet in a specific area including the groove is measured at regular intervals is set as a virtual plane, and a value of V2/V1 is more than 0.10 and less than 0.80, wherein V1 is a space volume of recess parts recessed from the virtual plane and V2 is a volume of projection parts projected from the virtual plane.
    Type: Grant
    Filed: March 31, 2017
    Date of Patent: May 26, 2020
    Assignee: NIPPON STEEL CORPORATION
    Inventors: Takahito Mizumura, Fumiaki Takahashi, Masato Mizokami, Hisashi Mogi, Hideyuki Hamamura, Hirofumi Imai, Shinya Hayashi, Kenichi Murakami
  • Publication number: 20200126709
    Abstract: A wound core is formed by laminating a plurality of bent bodies formed from a grain-oriented electrical steel sheet having a coating containing phosphorus formed on a surface, in a sheet thickness direction of the grain-oriented electrical steel sheet, in which the bent body is formed in a rectangular shape by having four flat portions and four corner portions adjacent to the flat portions, the corner portion has a bent region having a total bending angle of approximately 90° in a side view, the number of deformation twins present in the bent region in the side view is five or less per 1 mm of a length of a center line in the bent region in the sheet thickness direction, and the amount of phosphorus eluted from the corner portion in a case of being boiled in water for 30 minutes is 6.0 mg or less per 1 m2 of a surface area of the corner portion.
    Type: Application
    Filed: January 10, 2018
    Publication date: April 23, 2020
    Applicant: NIPPON STEEL CORPORATION
    Inventors: Takahito MIZUMURA, Masato MIZOKAMI, Masao YABUMOTO, Toshihiko UEMURA, Eisuke MINEMATSU, Fumiaki TAKAHASHI