Patents by Inventor Hiroyuki Kawata

Hiroyuki Kawata 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: 20180105908
    Abstract: A base material (13) included in a plated steel sheet (1) includes a structure, at a ¼ sheet thickness position, represented by, in volume fraction: tempered martensite: 3.0% or more; ferrite: 4.0% or more; and retained austenite: 5.0% or more. An average hardness of the tempered martensite in the base material (13) is 5 GPa to 10 GPa, and a part or all of the tempered martensite and the retained austenite in the base material form an M-A. A volume fraction of ferrite in a decarburized ferrite layer (12) included in the plated steel sheet (1) is 120% or more of the volume fraction of the ferrite in the base material (13) at the ¼ sheet thickness position, an average grain diameter of the ferrite in the decarburized ferrite layer (12) is 20 ?m or less, a thickness of the decarburized ferrite layer (12) is 5 ?m to 200 ?m, a volume fraction of tempered martensite in the decarburized ferrite layer (12) is 1.
    Type: Application
    Filed: April 22, 2016
    Publication date: April 19, 2018
    Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Koutarou HAYASHI, Akihiro UENISHI, Masaharu KAMEDA, Jun HAGA, Kunio HAYASHI, Kohichi SANO, Hiroyuki KAWATA
  • Publication number: 20180100213
    Abstract: A hot-rolled steel sheet according to the present embodiment has a chemical composition containing, in mass %: C: 0.07 to 0.30%, Si: more than 1.0 to 2.8%, Mn: 2.0 to 3.5%, P: 0.030% or less, S: 0.010% or less, Al: 0.01 to less than 1.0%, N: 0.01% or less, O: 0.01% or less, and one or more types selected from the group consisting of Sb, Sn and Te in a total amount of 0.03 to 0.30%, with a balance being Fe and impurities, and satisfying Formula (1). The micro-structure of the hot-rolled steel sheet includes ferrite and pearlite in a total amount of 50 area % or more. The tensile strength of the hot-rolled steel sheet is 900 MPa or less. Si+Mn?3.20??(1) Where, a content (mass %) of a corresponding element is substituted for each symbol of an element in Formula (1).
    Type: Application
    Filed: April 14, 2016
    Publication date: April 12, 2018
    Inventors: Yasuaki TANAKA, Mutsumi SAKAKIBARA, Takafumi YOKOYAMA, Hiroyuki KAWATA, Natsuko SUGIURA, Yasumitsu KONDO
  • Publication number: 20180079026
    Abstract: A spot welding method able to simply prevent liquid metal embrittlement cracks in spot welding of plated steel sheets, comprising, before spot welding, removing the plating at least in a zone including the inside of a circle centered at a scheduled location where the center of the nugget is formed and having an outer circumference of the inside of the outer edge of a weld affected zone or a zone at the mated surfaces of the steel sheets to be welded at the inside of a circle sharing a center of a scheduled location becoming the center of the nugget formed at the mated surfaces of the steel sheets and having an outer circumference of the inside of the outer edge of a weld affected zone
    Type: Application
    Filed: March 30, 2016
    Publication date: March 22, 2018
    Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Yasunobu MIYAZAKI, Fuminori WATANABE, Chisato WAKABAYASHI, Kunio HAYASHI, Hiroyuki KAWATA, Seiji FURUSAKO, Sho MATSUI
  • Patent number: 9896751
    Abstract: High strength steel sheet and high strength galvanized steel sheet which are excellent in shapeability which secure a tensile maximum strength 900 MPa or more high strength while obtaining excellent ductility and stretch flangeability, which sheets have predetermined compositions of ingredients, have steel sheet structures which contain volume fraction 1 to 20% of residual austenite phases, and which have martensite transformation points of the residual austenite phases of ?60° C. or less.
    Type: Grant
    Filed: July 27, 2012
    Date of Patent: February 20, 2018
    Assignee: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Hiroyuki Kawata, Naoki Maruyama, Akinobu Murasato, Akinobu Minami, Takeshi Yasui, Yuji Yamaguchi, Natsuko Sugiura
  • Publication number: 20170314115
    Abstract: A hot-dip galvanized steel sheet includes a base steel sheet and a hot-dip galvanized layer formed on at least one surface of the base steel sheet, in which the hot-dip galvanized layer includes Fe in a content of more than 0% to 5% or less, Al in a content of more than 0% to 1.0% or less, and columnar grains formed by a ? phase on the surface of the steel sheet, further, 20% or more of the entire interface between the hot-dip galvanized layer and the base steel sheet is coated with the ? phase, and a ratio of an interface formed between ? grains in which coarse oxides are present among ? grains and the base steel sheet with respect to the entire interface between the ? phase and the base steel sheet in the hot-dip galvanized layer is 50% or less, the base steel sheet has predetermined chemical components and a refined layer in direct contact with the interface between the base steel sheet and the hot-dip galvanized layer, an average thickness of the refined layer is 0.1 to 5.
    Type: Application
    Filed: November 5, 2015
    Publication date: November 2, 2017
    Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Hiroyuki KAWATA, Takeshi YASUI, Kohei UEDA, Naoki MARUYAMA, Yuji YAMAGUCHI, Satoshi UCHIDA, Ryosuke KOMAMI, Hayato ARAI, Toyomitsu NAKAMURA
  • Publication number: 20170314116
    Abstract: A hot-dip galvanized steel sheet wherein the hot-dip galvanized steel sheet comprises a base steel sheet and a hot-dip galvanized layer, a ferrite phase is, by volume fraction, 50% or less in a range of ? thickness to ? thickness centered at a position of ¼ thickness from the surface of the base steel sheet, a hard structure is 50% or more, wherein the hot-dip galvanized steel sheet has the hot-dip galvanized layer in which Fe is 5.0% or less and Al is 1.0% or less, and columnar grains formed of a ? phase is 20% or more in an entire interface between the plated layer and the base steel sheet, on the surface of the base steel sheet in which a volume fraction of a residual austenite is 3% or less and a ratio of a volume fraction of the hard structure is 0.10 times or more to 0.
    Type: Application
    Filed: November 5, 2015
    Publication date: November 2, 2017
    Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Hiroyuki KAWATA, Takeshi YASUI, Kohei UEDA, Naoki MARUYAMA, Yuji YAMAGUCHI, Satoshi UCHIDA, Ryosuke KOMAMI, Hayato ARAI, Toyomitsu NAKAMURA
  • Publication number: 20170313028
    Abstract: A hot-dip galvanized steel sheet wherein the hot-dip galvanized steel sheet comprises a base steel sheet and a hot-dip galvanized layer, a ferrite phase is, by volume fraction, 40% or more and 97% or less in a range of ? thickness to ? thickness centered at a position of ¼ thickness from the surface of the base steel sheet, a hard structure is 3% or more in total, wherein the hot-dip galvanized steel sheet has the hot-dip galvanized layer in which Fe is 5.0% or less and Al is 1.0% or less, and columnar grains formed of a ? phase is 20% or more in an entire interface between the plated layer and the base steel sheet on the surface of the base steel sheet in which a ratio of a volume fraction of the hard structure in a surface layer range of 20 ?m depth in a steel sheet direction from an interface between the hot-dip galvanized layer and the base steel sheet is 0.10 times or more to 0.
    Type: Application
    Filed: November 5, 2015
    Publication date: November 2, 2017
    Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Hiroyuki KAWATA, Takeshi YASUI, Kohei UEDA, Naoki MARUYAMA, Yuji YAMAGUCHI, Satoshi UCHIDA, Ryosuke KOMAMI, Hayato ARAI, Yasuhiro NAKASHIMA, Toyomitsu NAKAMURA
  • Publication number: 20170305114
    Abstract: A hot-dip galvanized steel sheet includes a base steel sheet and a hot-dip galvanized layer formed on at least one surface of the base steel sheet, in which the hot-dip galvanized layer includes Fe in a content of more than 0% to 5% or less, Al in a content of more than 0% to 1.0% or less, and columnar grains formed by a ? phase on the surface of the steel sheet, further, 20% or more of the entire interface between the hot-dip galvanized layer and the base steel sheet is coated with the ? phase, and a ratio of an interface formed between grains in which coarse oxides are present among grains and the base steel sheet with respect to the entire interface between the ? phase and the base steel sheet in the hot-dip galvanized layer is 50% or less, the base steel sheet has predetermined chemical components and a refined layer in direct contact with the interface between the base steel sheet and the hot-dip galvanized layer, an average thickness of the refined layer is 0.1 to 5.
    Type: Application
    Filed: November 5, 2015
    Publication date: October 26, 2017
    Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Hiroyuki KAWATA, Takeshi YASUI, Kohei UEDA, Naoki MARUYAMA, Yuji YAMAGUCHI, Satoshi UCHIDA, Ryosuke KOMAMI, Hayato ARAI, Toyomitsu NAKAMURA
  • Patent number: 9708679
    Abstract: There is provided a high-strength hot-dip galvanized steel sheet and the like excellent in mechanical cutting property, which are capable of obtaining high ductility while ensuring high strength with maximum tensile strength of 900 MPa or more. The high-strength hot-dip galvanized steel sheet has a sheet thickness of 0.6 to 5.0 mm and has a plating layer on a surface of a steel sheet with component compositions being set in appropriate ranges, in which the steel sheet structure contains a 40 to 90% ferrite phase and a 3% or more retained austenite phase by volume fraction. In the retained austenite phase, a solid solution carbon amount is 0.70 to 1.00%, an average grain diameter is 2.0 ?m or less, an average distance between grains is 0.1 to 5.0 ?m, a thickness of a decarburized layer in a steel sheet surface layer portion is 0.01 to 10.0 ?m, an average grain diameter of oxides contained in the steel, sheet surface layer portion is 30 to 120 nm and an average density thereof is 1.
    Type: Grant
    Filed: September 28, 2012
    Date of Patent: July 18, 2017
    Assignee: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Hiroyuki Kawata, Naoki Maruyama, Akinobu Murasato, Akinobu Minami, Takeshi Yasui, Takuya Kuwayama, Hiroyuki Ban, Kaoru Hiramatsu
  • Patent number: 9702035
    Abstract: A base steel sheet has a hot-dip galvanized layer formed on a surface thereof, in which, in a steel sheet structure in a range of ? thickness to ? thickness centered around ¼ thickness of a sheet thickness from a surface, a volume fraction of a retained austenite phase is 5% or less, and a total volume fraction of phases of bainite, bainitic ferrite, fresh martensite, and tempered martensite is 40% or more, an average effective crystal grain diameter is 5.0 ?m or less, a maximum effective crystal grain diameter is 20 ?m or less, and a decarburized layer with a thickness of 0.01 ?m to 10.0 ?m is formed on a surface layer portion, in which a density of oxides dispersed in the decarburized layer is 1.0×1012 to 1.0×1016 oxides/m2, and an average grain diameter of the oxides is 500 nm or less.
    Type: Grant
    Filed: December 3, 2014
    Date of Patent: July 11, 2017
    Assignee: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Hiroyuki Kawata, Naoki Maruyama, Akinobu Murasato, Akinobu Minami, Takeshi Yasui, Takuya Kuwayama, Hiroyuki Ban, Kaoru Hiramatsu
  • Patent number: 9694561
    Abstract: High strength steel sheet which secures tensile maximum strength 900 MPa or more high strength while having excellent shapeability, which high strength steel sheet which is excellent in shapeability characterized by having a predetermined composition of ingredients, by the steel sheet structure including a ferrite phase and martensite phase, by the ratio of Cu particles incoherent with the bcc iron being 15% or more with respect to the Cu particles as a whole, by a density of Cu particles in the ferrite phase being 1.0×1018/m3 or more, and by an average particle size of Cu particles in the ferrite phase being 2.0 nm or more.
    Type: Grant
    Filed: July 27, 2012
    Date of Patent: July 4, 2017
    Assignee: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Hiroyuki Kawata, Naoki Maruyama, Akinobu Murasato, Akinobu Minami, Masafumi Azuma, Takuya Kuwayama, Shigeru Yonemura
  • Patent number: 9610648
    Abstract: Provided is a spot welded joint (10) which includes at least one thin steel plate with a tensile strength of 750 MPa to 1850 MPa and a carbon equivalent Ceq of equal to or more than 0.22 mass % to 0.55 mass % and in which a nugget (3) is formed in an interface of the thin steel plates (1A, 1B). In a nugget outer layer zone, a microstructure consists of a dendrite structure in which an average value of arm intervals is equal to or less than 12 ?m, an average grain diameter of carbides contained in the microstructure is 5 nm to 100 nm, and a number density of carbides is equal to or more than 2×106/mm2.
    Type: Grant
    Filed: September 18, 2014
    Date of Patent: April 4, 2017
    Assignee: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Hatsuhiko Oikawa, Hideki Hamatani, Masafumi Azuma, Noriyuki Suzuki, Fuminori Watanabe, Naoki Maruyama, Hiroyuki Kawata
  • Patent number: 9551057
    Abstract: Provided are: a galvannealed steel sheet, improved in the adhesiveness of a plated layer with a base steel sheet, as a galvannealed steel sheet, prepared by using a high-strength steel sheet as a base material; and a method for producing the galvannealed steel sheet. A galvannealed layer is formed on the base steel sheet including a high-strength steel having a predetermined composition. The average amount of Fe in the galvannealed layer is 8.0 to 12.0%. The absolute value of a difference (?Fe) between the amount of Fe in the vicinity of an interface with the base steel sheet and the amount of Fe in the vicinity of the external surface of the plated layer in the plated layer is 0.0 to 3.0%.
    Type: Grant
    Filed: July 27, 2012
    Date of Patent: January 24, 2017
    Assignee: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Hiroyuki Kawata, Naoki Maruyama, Akinobu Murasato, Akinobu Minami, Takeshi Yasui
  • Patent number: 9479025
    Abstract: A drive device includes a rotating electric machine, a substrate, a first drive element, a second drive element, a first extension line, and a second extension line. The rotating electric machine including a stator with a first winding group and a second winding group wound on the stator in at least three phases. The first extension line and the first drive element, as well as the second extension line and the second drive element have respectively reversed phase orders in an arrangement of the phase orders from an end close to a reference position toward an other end of the arrangement. In such manner, variation of wiring lengths from an electric power supply region among different phases is reduced.
    Type: Grant
    Filed: July 29, 2015
    Date of Patent: October 25, 2016
    Assignee: DENSO CORPORATION
    Inventors: Hiroyuki Kawata, Masashi Yamasaki, Takeshi Sawada
  • Patent number: 9473004
    Abstract: A drive device that includes a motor having a rotor disposed relative to a stator, a cover having a one-end-closed cylinder shape and positioned on one axial end side of the motor, and a substrate on the inside of the cover perpendicular to a motor shaft having electronic components implemented on the substrate. The drive device also includes a connector positioned on a motor side of the substrate with an opening that is connectable to an external terminal. The opening of the connector faces outward relative to the motor shaft. The drive device further includes a heat sink having a frame end part and a heat receiving part formed in one body. The drive device increases heat capacity of the heat sink without increasing its height.
    Type: Grant
    Filed: July 29, 2015
    Date of Patent: October 18, 2016
    Assignee: DENSO CORPORATION
    Inventors: Yuuta Kadoike, Hideki Kabune, Hiroyuki Kawata
  • Patent number: 9359004
    Abstract: A driver unit has a rotating electric machine and a frame member that is disposed on one axial end of the rotating electric machine. A substrate is fixed onto one surface of the frame member which faces away from the rotating electric machine. Switching elements constituting inverters for switching power supply to winding groups are mounted on a first surface for enabling heat dissipation toward the frame member. An Integrated Circuit (IC) is mounted on the first surface for enabling heat dissipation toward the frame member. An electronic component is mounted on a second surface at an overlapping position that at least partially overlaps a mounting position of the IC.
    Type: Grant
    Filed: July 29, 2015
    Date of Patent: June 7, 2016
    Assignee: DENSO CORPORATION
    Inventors: Hiroyuki Kawata, Masashi Yamasaki
  • Patent number: 9329090
    Abstract: In an electronic device, a heat generation part pattern is connected to a heat generating element to heat from the heat generating element. A temperature detecting element is disposed adjacent to a first surface of a substrate. A direct under layer pattern is disposed on a second surface of the substrate opposite to the temperature detecting element in an area including a portion corresponding to the temperature detecting element. An interlayer connection pillar connects between the heat generation part pattern and the direct under layer pattern to conduct heat. The heat generated from the heat generating element is effectively conducted to the temperature detecting element through the heat generation part pattern, the interlayer connection pillar, and the direct under layer pattern, and thus the temperature detecting element accurately detects the temperature of the heat generating element.
    Type: Grant
    Filed: December 22, 2014
    Date of Patent: May 3, 2016
    Assignee: DENSO CORPORATION
    Inventors: Junichi Ogoshi, Hiroyuki Kawata, Toshio Tsutsui, Shinsuke Ota
  • Publication number: 20160082543
    Abstract: By obtaining a spot-welded joint being a spot-welded joint formed by overlapping a plurality of pieces of steel plates (1A, 1B) and performing spot welding on the steel plates, including a high-strength steel plate whose tensile strength is 750 (MPa) to 2500 (MPa), being at least one piece of steel plate out of the plurality of pieces of steel plates, in which a carbon equivalent Ceq of the high-strength steel plate is 0.20 mass % to 0.55 mass %, and ten or more of iron-based carbides in each of which a length of a longest portion is 0.1 (?m) or more exist in a square region 103 within a heat-affected zone 4 of a cross section that passes through a center of a welding mark, and is cut along a plate thickness direction of the steel plates (1A, 1B), a cross tensile strength of the spot-welded joint to be formed is improved.
    Type: Application
    Filed: June 2, 2014
    Publication date: March 24, 2016
    Applicant: NIPPON STEEL & SUMITOMO METAL CORPORATION
    Inventors: Chisato WAKABAYASHI, Fuminori WATANABE, Seiji FURUSAKO, Yasunobu MIYAZAKI, Hiroyuki KAWATA, Tohru OKADA, Hideki HAMATANI
  • Publication number: 20160036289
    Abstract: A drive device includes a rotating electric machine, a substrate, a first drive element, a second drive element, a first extension line, and a second extension line. The rotating electric machine including a stator with a first winding group and a second winding group wound on the stator in at least three phases. The first extension line and the first drive element, as well as the second extension line and the second drive element have respectively reversed phase orders in an arrangement of the phase orders from an end close to a reference position toward an other end of the arrangement. In such manner, variation of wiring lengths from an electric power supply region among different phases is reduced.
    Type: Application
    Filed: July 29, 2015
    Publication date: February 4, 2016
    Inventors: Hiroyuki Kawata, Masashi Yamasaki, Takeshi Sawada
  • Publication number: 20160036303
    Abstract: A drive device that includes a motor having a rotor disposed relative to a stator, a cover having a one-end-closed cylinder shape and positioned on one axial end side of the motor, and a substrate on the inside of the cover perpendicular to a motor shaft having electronic components implemented on the substrate. The drive device also includes a connector positioned on a motor side of the substrate with an opening that is connectable to an external terminal. The opening of the connector faces outward relative to the motor shaft. The drive device further includes a heat sink having a frame end part and a heat receiving part formed in one body. The drive device increases heat capacity of the heat sink without increasing its height.
    Type: Application
    Filed: July 29, 2015
    Publication date: February 4, 2016
    Inventors: Yuuta Kadoike, Hideki Kabune, Hiroyuki Kawata