Patents by Inventor Kunihiro Senda

Kunihiro Senda 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: 10533969
    Abstract: To predict the iron loss of a non-oriented electrical steel sheet after shearing, a non-oriented electrical steel sheet is sheared to a certain width, and iron loss Wt(B0) of the non-oriented electrical steel sheet after shearing is estimated according to a predetermined relational expression based on iron loss Wn(B1) in a non-machining-affected zone in which no machining strain is introduced by the shearing and iron loss Wi(B2) in a machining affected zone in which machining strain is introduced.
    Type: Grant
    Filed: November 2, 2015
    Date of Patent: January 14, 2020
    Assignee: JFE STEEL CORPORATION
    Inventors: Takeshi Omura, Yoshiaki Zaizen, Kunihiro Senda
  • Publication number: 20190312495
    Abstract: A punch processing method for electrical steel sheets to manufacture core segments includes: stacking a plurality of electrical steel sheets; and punching out the plurality of electrical steel sheets in a stacked state simultaneously to manufacture the core segments, wherein in a case where the core segments are applied to a stator core in which a maximum magnetic flux density at a tooth portion is to be higher than a maximum magnetic flux density at a back yoke portion, degrees of Vickers hardness of an electrical steel sheet located second from a bottom side and above in the stacked state are set to 180 HV or higher, and 10 HV or higher than a value of degree of Vickers hardness of an electrical steel sheet located on the bottom side in the stacked state.
    Type: Application
    Filed: August 22, 2017
    Publication date: October 10, 2019
    Applicant: JFE STEEL CORPORATION
    Inventors: Kunihiro SENDA, Masanori UESAKA, Yoshihiko ODA
  • Publication number: 20190189318
    Abstract: A non-oriented electrical steel sheet has low iron loss even under inverter excitation and can be suitably used as the iron core of a motor. The non-oriented electrical steel sheet has a specific chemical composition and an average grain size r of 40 ?m to 120 ?m. An area ratio R of a total area of grains having a grain size of ? or less of the thickness of the steel sheet to a cross-sectional area of the steel sheet is 2% or greater, and the average grain size r (?m) and the area ratio R (%) satisfy a condition represented by Expression (1), R>?2.4×r+200 (1).
    Type: Application
    Filed: December 14, 2016
    Publication date: June 20, 2019
    Applicant: JFE STEEL CORPORATION
    Inventors: Masanori UESAKA, Kunihiro SENDA, Takeshi OMURA
  • Publication number: 20190099800
    Abstract: A method of manufacturing a laminated iron core includes: inserting a plurality of electrical steel strips in a superposed state to feed rolls including a pair of upper and lower feed rolls that are driven by a drive device to feed the electrical steel strips in a superposed state into a die having a plurality of punching processes in sequence; joining a part or all of the superposed electrical steel strips together before entering the die or at an upstream stage portion of the die after feeding out the electrical steel strips from the pair of upper and lower feed rolls; and punching simultaneously the plurality of electrical steel strips in a superposed state in the die.
    Type: Application
    Filed: March 7, 2017
    Publication date: April 4, 2019
    Applicant: JFE STEEL CORPORATION
    Inventors: Kunihiro SENDA, Masanori UESAKA, Yoshihiko ODA
  • Publication number: 20180350518
    Abstract: A laminated core manufacturing device includes: an overlapping unit configured to overlap the plurality of laminated core materials conveyed along different conveyance routes; an edge position correction unit configured to align edge positions in a width direction of the plurality of laminated core materials between the plurality of laminated core materials and to correct shift of each edge position of the plurality of laminated core materials with respect to a standard edge position; an uplift prevention unit configured to prevent uplift of the plurality of laminated core materials; and a punching unit configured to punch out the plurality of laminated core materials which are overlapped by the overlapping unit and have been subjected to a process to align the edge positions and to correct shift of the edge positions performed by the edge position correction unit, and a process to prevent the uplift performed by the uplift prevention unit.
    Type: Application
    Filed: August 22, 2016
    Publication date: December 6, 2018
    Applicant: JFE STEEL CORPORATION
    Inventors: Masanori Uesaka, Kunihiro Senda, Yoshihiko Oda, Yoshihide Kamitani, Yasuhito Shioiri
  • Publication number: 20180178267
    Abstract: A Laminated core manufacturing device includes: an overlapping unit configured to overlap the plurality of laminated core materials conveyed along different conveyance routes; an edge aligning unit configured to align edge positions in a width direction of the plurality of laminated core materials between the plurality of laminated core materials; an uplift prevention unit configured to prevent uplift of the plurality of laminated core materials; an edge position correction unit configured to correct the edge positions in the width direction of the plurality of laminated core materials; and a punching unit configured to punch out the plurality of laminated core materials which are overlapped by the overlapping unit and have been subjected to an edge position alignment process performed by the edge aligning unit, an uplift prevention process performed by the uplift prevention unit, and an edge position correction process performed by the edge position correction unit.
    Type: Application
    Filed: August 22, 2016
    Publication date: June 28, 2018
    Applicant: JFE STEEL CORPORATION
    Inventors: Masanori Uesaka, Kunihiro Senda, Yoshihiko Oda, Yoshihide Kamitani, Yasuhito Shioiri
  • Publication number: 20180037966
    Abstract: A grain-oriented electrical steel sheet having a composition containing, in mass %, C: 0.005% or less, Si: 2.0% to 4.5%, and Mn: 0.5% or less, and also containing Sb and P in respective ranges satisfying 0.01%?[% Sb]?0.20% and 0.02%?[% P]?2.0×[% Sb], with a balance being Fe and incidental impurities, wherein when the steel sheet is excited to 1.0 T at 50 Hz in a rolling transverse direction, a magnetizing force (TD-H10) and an iron loss (TD-W10) are respectively (TD-H10)?200 A/m and (TD-W10)?1.60 W/kg. Thus, a grain-oriented electrical steel sheet having excellent transformer core loss can be obtained industrially stably at low cost.
    Type: Application
    Filed: February 13, 2015
    Publication date: February 8, 2018
    Applicant: JFE STEEL CORPORATION
    Inventors: Yasuyuki HAYAKAWA, Kunihiro SENDA, Takashi TERASHIMA
  • Publication number: 20180001369
    Abstract: A punching method includes: punching out a plurality of electrical steel sheets in a stacked state by a mold, wherein sheet thicknesses of the electrical steel sheets are set to be 0.35 mm or less, a Vickers hardness (test force 1 kg) of the sheets is set to be 150 to 400, and an average crystal grain size of the sheets is set to be 50 to 250 ?m, a clearance of the mold is set to be 7% or more of a minimum sheet thickness of the sheet thicknesses of the electrical steel sheets and equal to or lower than 7% of a total sheet thickness of the electrical steel sheets, and a pressure that a sheet presser of the mold applies to the electrical steel sheets is set to be 0.10 MPa or more.
    Type: Application
    Filed: January 7, 2016
    Publication date: January 4, 2018
    Applicant: JFE STEEL CORPORATION
    Inventors: Kunihiro SENDA, Masanori UESAKA, Yoshihiko ODA
  • Publication number: 20170368590
    Abstract: A punch processing method for a laminated iron core includes sequentially feeding the steel sheets to a mold; and performing a plurality of processes in the mold, the plurality of processes includes fixing the steel sheets being stacked to each other at a first fixing part that is positioned outside a closed curved line corresponding to an outermost periphery of the laminated iron core and a second fixing part that is positioned in a portion that finally serves as the laminated iron core; and performing punch processing on the outermost periphery of the laminated iron core while the steel sheets are stacked.
    Type: Application
    Filed: December 25, 2015
    Publication date: December 28, 2017
    Applicant: JFE STEEL CORPORATION
    Inventors: Kunihiro Senda, Masanori Uesaka, Yoshihiko Oda
  • Publication number: 20170342519
    Abstract: A material for laminated iron cores is used as plural steel sheets to be overlapped with one another and punched when a laminated iron core is manufactured. A surface roughness of the steel sheets forming the material for laminated iron cores is at an arithmetic mean roughness Ra of 0.40 [?m] or less, and a sheet thickness deviation in a sheet width direction of at least a portion used as the laminated iron core is 3 [?m] or less per 500 [mm], the portion being of the steel sheets forming the material for laminated iron cores.
    Type: Application
    Filed: October 13, 2015
    Publication date: November 30, 2017
    Applicant: JFE STEEL CORPORATION
    Inventors: MASANORI UESAKA, Kunihiro Senda, Yoshihiko Oda
  • Publication number: 20170315093
    Abstract: To predict the iron loss of a non-oriented electrical steel sheet after shearing, a non-oriented electrical steel sheet is sheared to a certain width, and iron loss Wt(B0) of the non-oriented electrical steel sheet after shearing is estimated according to a predetermined relational expression based on iron loss Wn(B1) in a non-machining-affected zone in which no machining strain is introduced by the shearing and iron loss Wi(B2) in a machining affected zone in which machining strain is introduced.
    Type: Application
    Filed: November 2, 2015
    Publication date: November 2, 2017
    Applicant: JFE STEEL CORPORATION
    Inventors: Takeshi OMURA, Yoshiaki ZAIZEN, Kunihiro SENDA
  • Publication number: 20170263357
    Abstract: A method of manufacturing a grain oriented electrical steel sheet includes subjecting a steel slab to a rolling process including cold rolling to obtain a steel sheet with a final sheet thickness, the steel slab containing by mass % C: 0.01% to 0.20%, Si: 2.0% to 5.0%, Mn: 0.03% to 0.20%, sol. Al: 0.010% to 0.05%, N: 0.0010% to 0.020%, at least one element selected from S and Se in a total of 0.005% to 0.040%, and the balance including Fe and incidental impurities; forming, by a chemical process, a linear groove extending in a direction forming an angle of 45° or less with a direction orthogonal to a rolling direction of the steel sheet; subjecting the steel sheet to decarburization annealing; applying an annealing separator thereon mainly composed of MgO; and subjecting the steel sheet to final annealing to manufacture a grain oriented electrical steel sheet.
    Type: Application
    Filed: May 26, 2017
    Publication date: September 14, 2017
    Inventors: Kunihiro Senda, Hirotaka Inoue, Seiji Okabe
  • Patent number: 9704626
    Abstract: A grain-oriented electrical steel sheet has low iron loss properties obtained though magnetic domain refining treatment by a chemical means. The steel sheet has a linear groove extending in a direction forming an angle of 45° or less with a direction orthogonal to a rolling direction of the steel sheet, in which presence frequency of fine grains with a length in the rolling direction of 1 mm or less in a floor portion of the groove is 10% or less, including 0% indicative of the absence of fine grains, the groove is provided with a forsterite film in an amount of 0.6 g/m2 or more in terms of Mg coating amount per one surface of the steel sheet, and an average of angles (? angles) formed by <100> axes of secondary recrystallized grains facing the rolling direction and a rolling plane of the steel sheet is 3° or less.
    Type: Grant
    Filed: April 26, 2012
    Date of Patent: July 11, 2017
    Assignee: JFE Steel Corporation
    Inventors: Kunihiro Senda, Hirotaka Inoue, Seiji Okabe
  • Patent number: 9617615
    Abstract: Provided is a grain-oriented electrical steel sheet including: a forsterite base film formed on a surface of the steel sheet; and an insulating tension coating formed on the base film, in which when Ti intensity FX(Ti), Al intensity FX(Al), and Fe intensity FX(Fe) obtained through quantitative analysis by performing fluorescent X-ray analysis on the surface of the steel sheet satisfy FX(Ti)/FX(Al)?0.15 and FX(Ti)/FX(Fe)?0.004, the frequency of crystal boundaries of secondary recrystallized grains in the direction orthogonal to the rolling direction is 20 grain boundaries/100 mm or less, the mean thickness of the forsterite base film t(Fo) and the thickness of the insulating tension coating t(C) satisfies t(Fo)/t(C)?0.3, and magnetic domain refining treatment is performed by irradiation with a laser beam, plasma flame, or electron beam, a sufficient iron loss reducing effect is achieved in a range where coating detachment does not occur.
    Type: Grant
    Filed: August 26, 2014
    Date of Patent: April 11, 2017
    Assignee: JFE Steel Corporation
    Inventors: Kunihiro Senda, Shigehiro Takajo, Tomoyuki Okubo
  • Publication number: 20160230240
    Abstract: Provided is a grain-oriented electrical steel sheet including: a forsterite base film formed on a surface of the steel sheet; and an insulating tension coating formed on the base film, in which when Ti intensity FX(Ti), Al intensity FX(Al), and Fe intensity FX(Fe) obtained through quantitative analysis by performing fluorescent X-ray analysis on the surface of the steel sheet satisfy FX(Ti)/FX(Al)?0.15 and FX(Ti)/FX(Fe)?0.004, the frequency of crystal boundaries of secondary recrystallized grains in the direction orthogonal to the rolling direction is 20 grain boundaries/100 mm or less, the mean thickness of the forsterite base film t(Fo) and the thickness of the insulating tension coating t(C) satisfies t(Fo)/t(C)?0.3, and magnetic domain refining treatment is performed by irradiation with a laser beam, plasma flame, or electron beam, a sufficient iron loss reducing effect is achieved in a range where coating detachment does not occur.
    Type: Application
    Filed: August 26, 2014
    Publication date: August 11, 2016
    Applicant: JFE STEEL CORPORATION
    Inventors: Kunihiro Senda, Shigehiro Takajo, Tomoyuki Okubo
  • Patent number: 9290824
    Abstract: In a method of producing a grain-oriented electrical steel sheet by hot-rolling a steel slab of a chemical composition containing C: 0.001˜0.10%, Si: 1.0˜5.0%, Mn: 0.01˜1.0%, at least one of S and Se: 0.01˜0.05% in total, sol. Al: 0.003˜0.050%, N: 0.001˜0.020% by mass, subjecting to cold rolling, a primary recrystallization annealing, application of an annealing separator mainly composed of MgO and a finish annealing, a temperature rising rate S1 between 500˜600° C. in the primary recrystallization annealing is made to not less than 100° C./s and a temperature rising rate S2 between 600˜700° C. is made to 30° C./s˜0.6×S1° C./s, while a total content W (mol %) of an element having an ionic radius of 0.6˜1.3 ? and an attracting force between the ion and oxygen of not more than 0.7 ??2 included in the annealing separator to MgO is adjusted to satisfy 0.01S2?5.5?Ln (W)?0.01S2?4.3 to produce a grain-oriented electrical steel sheet having excellent iron loss properties and coating properties.
    Type: Grant
    Filed: August 15, 2012
    Date of Patent: March 22, 2016
    Assignee: JFE Steel Corporation
    Inventors: Makoto Watanabe, Yukihiro Shingaki, Toshito Takamiya, Tomoyuki Okubo, Kunihiro Senda
  • Publication number: 20150243419
    Abstract: In a method for producing a grain-oriented electrical steel sheet by hot rolling a steel slab containing, in terms of mass %, C: 0.001˜0.20%, Si: 1.0˜5.0%, Mn: 0.03˜1.0%, one or two of S and Se: 0.005˜0.040% in total, sol. Al: 0.003˜0.050% and N: 0.0010˜0.020%, subjecting to a cold rolling to a final thickness and to a primary recrystallization annealing, applying an annealing separator composed mainly of MgO and then subjecting to final annealing, a heating rate S1 at a zone of 500˜600° C. in a heating process of the primary recrystallization annealing is not less than 100° C./s and a heating rate S2 at a zone of 600˜700° C. is a range of 30˜(0.5×S1)° C./s and an oxidation potential PH2O/PH2 of an atmosphere at a zone of 500˜700° C. is preferably not more than 0.05, whereby secondary recrystallized grains are refined over a full length of a product coil to decrease an iron loss.
    Type: Application
    Filed: September 27, 2012
    Publication date: August 27, 2015
    Inventors: Kunihiro Senda, Makoto Watanabe, Yukihiro Shingaki, Takeshi Omura
  • Publication number: 20150111004
    Abstract: A grain-oriented electrical steel sheet has low iron loss properties obtained though magnetic domain refining treatment by a chemical means. The steel sheet has a linear groove extending in a direction forming an angle of 45° or less with a direction orthogonal to a rolling direction of the steel sheet, in which presence frequency of fine grains with a length in the rolling direction of 1 mm or less in a floor portion of the groove is 10% or less, including 0% indicative of the absence of fine grains, the groove is provided with a forsterite film in an amount of 0.6 g/m2 or more in terms of Mg coating amount per one surface of the steel sheet, and an average of angles (3 angles) formed by <100> axes of secondary recrystallized grains facing the rolling direction and a rolling plane of the steel sheet is 3° or less.
    Type: Application
    Filed: April 26, 2012
    Publication date: April 23, 2015
    Applicant: JFE Steel Corporation
    Inventors: Kunihiro Senda, Hirotaka Inoue, Seiji Okabe
  • Publication number: 20150007908
    Abstract: In a method of producing a grain-oriented electrical steel sheet by hot-rolling a steel slab of a chemical composition containing C: 0.001˜0.10%, Si: 1.0˜5.0%, Mn: 0.01˜1.0%, at least one of S and Se: 0.01˜0.05% in total, sol. Al: 0.003˜0.050%, N: 0.001˜0.020% by mass, subjecting to cold rolling, a primary recrystallization annealing, application of an annealing separator mainly composed of MgO and a finish annealing, a temperature rising rate S1 between 500˜600° C. in the primary recrystallization annealing is made to not less than 100° C./s and a temperature rising rate S2 between 600˜700° C. is made to 30° C./s˜0.6×S1° C./s, while a total content W (mol %) of an element having an ionic radius of 0.6˜1.3 ? and an attracting force between the ion and oxygen of not more than 0.7 ??2 included in the annealing separator to MgO is adjusted to satisfy 0.01S2-5.5?Ln (W)?0.01S2?4.3 to produce a grain-oriented electrical steel sheet having excellent iron loss properties and coating properties.
    Type: Application
    Filed: August 15, 2012
    Publication date: January 8, 2015
    Applicant: JFE STEEL CORPORATION
    Inventors: Makoto Watanabe, Yukihiro Shingaki, Toshito Takamiya, Tomoyuki Okubo, Kunihiro Senda
  • Publication number: 20140338794
    Abstract: In the production of a grain-oriented electrical steel sheet by hot rolling a steel slab comprising C: 0.001˜0.10 mass %, Si: 1.0˜5.0 mass %, Mn: 0.01˜0.5 mass %, sol. Al: 0.003˜0.050 mass %, N: 0.0010˜0.020 mass %, one or two selected from S and Se: 0.005˜0.040 mass % in total, cold rolling, primary recrystallization annealing, and final annealing, a heating rate S1 between a temperature T1 (° C.): 500+2×(NB?NA) and a temperature T2 (° C.): 600+2×(NB?NA) in a heating process of the primary recrystallization annealing is set to not less than 80° C./sec, and an average heating rate S2 from the temperature T2 to 750° C. is set to 0.1˜0.7 times of S1, whereby a grain-oriented electrical steel sheet having a low iron loss over a full length of a product coil is obtained.
    Type: Application
    Filed: September 14, 2012
    Publication date: November 20, 2014
    Applicant: JFE STEEL CORPORATION
    Inventors: Yukihiro Shingaki, Makoto Watanabe, Kunihiro Senda