Patents by Inventor Takefumi Nakako

Takefumi Nakako 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: 10975899
    Abstract: A welded member includes a hot dip Zn-based alloy coated steel sheet as a base material and has excellent corrosion resistance and weld bead shear strength. In the welded member in which a lower sheet and an upper sheet, which are hot dip Zn-based alloy coated steel sheets, are stacked and arc-welded together, a weld bead is formed so that a cross-sectional width W satisfies the following formula 2T?W?6T, and a blowhole occupancy Br represented by the following formula becomes not more than 50%: Br=(?di/L)×100, where T represents a thickness of the hot dip Zn-based alloy coated steel sheet, di represents a length of an i-th blowhole observed in X-ray radiography, and L represents a length of the weld bead.
    Type: Grant
    Filed: September 15, 2017
    Date of Patent: April 13, 2021
    Assignee: NIPPON STEEL NISSHIN CO., LTD.
    Inventors: Kazuaki Hosomi, Tomokazu Nobutoki, Takefumi Nakako
  • Patent number: 10906113
    Abstract: Hot dip Zn-based alloy coated steel sheets (1, 1?) are arc-weld in such a way that (a) a current waveform is a pulsed current waveform in which (i) a peak current and a base current alternate with each other at a pulse period of 1 ms to 50 ms and (ii) an average welding current is 100 A to 350 A and (b) an average welding voltage is 20 V to 35 V. Each of the hot dip Zn-based alloy coated steel sheets (1, 1?) includes a coating layer that contains Zn as a main component and that contains Al at a concentration of 1.0% by mass to 22.0% by mass, and has a coating weight W of 15 g/m2 to 250 g/m2.
    Type: Grant
    Filed: February 2, 2016
    Date of Patent: February 2, 2021
    Assignee: Nisshin Steel Co., Ltd.
    Inventors: Kazuaki Hosomi, Tomokazu Nobutoki, Takefumi Nakako
  • Patent number: 10807177
    Abstract: The present invention provides a method for MIG brazing an Al alloy to a steel sheet so as to manufacture a lap joint member that excels in bonding strength with respect to the Al alloy. With the MIG brazing method, a bonding target sheet, specifically, an Al sheet or an Al alloy sheet is bonded to a hot dip Zn-based alloy coated steel sheet (1) whose coating layer contains Al in an amount of 1.0% by mass to 22.0% by mass. A target location of MIG brazing is a region between (i) an intersection (C) of one end of an end surface (6) of the bonding target sheet and the hot dip Zn-based alloy coated steel sheet and (ii) the other end (U) of the end surface of the bonding target sheet.
    Type: Grant
    Filed: February 21, 2018
    Date of Patent: October 20, 2020
    Assignee: NIPPON STEEL NISSHIN CO., LTD.
    Inventors: Kazuaki Hosomi, Kouki Tomimura, Takefumi Nakako
  • Patent number: 10792746
    Abstract: The present invention provides a method for laser brazing an Al alloy to a steel sheet so as to produce a lap joint member that excels in bonding strength with respect to the Al alloy. The laser brazing method includes a brazing step of forming a brazed part (9) for bonding an Al alloy (3) to a hot dip Zn-based alloy coated steel sheet (1) in which a coating layer (2) contains 1.0 to 22.0% by mass of Al and a coating weight per surface is 15 to 250 g/m2.
    Type: Grant
    Filed: February 21, 2018
    Date of Patent: October 6, 2020
    Assignee: NIPPON STEEL NISSHIN CO., LTD.
    Inventors: Kazuaki Hosomi, Kouki Tomimura, Takefumi Nakako
  • Publication number: 20200230743
    Abstract: A vacuum insulation panel manufacturing method that makes it possible to manufacture low-cost, high-performance vacuum insulation panels, and a vacuum insulation panel are provided.
    Type: Application
    Filed: April 8, 2020
    Publication date: July 23, 2020
    Inventors: Tsutomu AZUMA, Hirohisa MISHIMA, Takefumi NAKAKO
  • Patent number: 10710196
    Abstract: A vacuum insulation panel manufacturing method that makes it possible to manufacture low-cost, high-performance vacuum insulation panels, and a vacuum insulation panel are provided.
    Type: Grant
    Filed: December 21, 2018
    Date of Patent: July 14, 2020
    Assignee: NISSHIN STEEL CO., LTD.
    Inventors: Tsutomu Azuma, Hirohisa Mishima, Takefumi Nakako
  • Patent number: 10639743
    Abstract: A vacuum insulation panel manufacturing method that makes it possible to manufacture low-cost, high-performance vacuum insulation panels, and a vacuum insulation panel are provided.
    Type: Grant
    Filed: May 31, 2017
    Date of Patent: May 5, 2020
    Assignee: NIPPON STEEL NISSHIN CO., LTD.
    Inventors: Tsutomu Azuma, Hirohisa Mishima, Takefumi Nakako
  • Patent number: 10632564
    Abstract: A vacuum insulation panel manufacturing method that makes it possible to manufacture low-cost, high-performance vacuum insulation panels, and a vacuum insulation panel are provided.
    Type: Grant
    Filed: May 31, 2017
    Date of Patent: April 28, 2020
    Assignee: NIPPON STEEL NISSHIN CO., LTD.
    Inventors: Tsutomu Azuma, Hirohisa Mishima, Takefumi Nakako
  • Patent number: 10603733
    Abstract: The present invention provides a method for producing a TIG-welded stainless steel tube without adding H2 to a shielding gas, while inhibiting generation of a weld defect. The method is a method for producing a TIG-welded stainless steel tube and includes the steps of bending a stainless steel strip in a width direction so as to butt both edges against each other and TIG-welding the both edges thus butted. A pulse waveform of a pulse frequency of 40 Hz to 300 Hz is used as a current waveform of a welding power source.
    Type: Grant
    Filed: June 2, 2017
    Date of Patent: March 31, 2020
    Assignee: Nippon Steel Nisshin Co., Ltd.
    Inventors: Takefumi Nakako, Tomokazu Nobutoki, Hiroshi Asada
  • Publication number: 20200055133
    Abstract: The present invention provides a method for MIG brazing an Al alloy to a steel sheet so as to manufacture a lap joint member that excels in bonding strength with respect to the Al alloy. With the MIG brazing method, a bonding target sheet, specifically, an Al sheet or an Al alloy sheet is bonded to a hot dip Zn-based alloy coated steel sheet (1) whose coating layer contains Al in an amount of 1.0% by mass to 22.0% by mass. A target location of MIG brazing is a region between (i) an intersection (C) of one end of an end surface (6) of the bonding target sheet and the hot dip Zn-based alloy coated steel sheet and (ii) the other end (U) of the end surface of the bonding target sheet.
    Type: Application
    Filed: February 21, 2018
    Publication date: February 20, 2020
    Inventors: Kazuaki Hosomi, Kouki Tomimura, Takefumi Nakako
  • Publication number: 20200056643
    Abstract: A welded member includes a hot dip Zn-based alloy coated steel sheet as a base material and has excellent corrosion resistance and weld bead shear strength. In the welded member in which a lower sheet and an upper sheet, which are hot dip Zn-based alloy coated steel sheets, are stacked and arc-welded together, a weld bead is formed so that a cross-sectional width W satisfies the following formula 2T?W?6T, and a blowhole occupancy Br represented by the following formula (2) becomes not more than 50%: Br=(?di/L)×100, where T represents a thickness of the hot dip Zn-based alloy coated steel sheet, di represents a length of an i-th blowhole observed in X-ray radiography, and L represents a length of the weld bead.
    Type: Application
    Filed: September 15, 2017
    Publication date: February 20, 2020
    Inventors: Kazuaki Hosomi, Tomokazu Nobutoki, Takefumi Nakako
  • Publication number: 20200023453
    Abstract: The present invention provides a method for laser brazing an Al alloy to a steel sheet so as to produce a lap joint member that excels in bonding strength with respect to the Al alloy. The laser brazing method includes a brazing step of forming a brazed part (9) for bonding an Al alloy (3) to a hot dip Zn-based alloy coated steel sheet (1) in which a coating layer (2) contains 1.0 to 22.0% by mass of Al and a coating weight per surface is 15 to 250 g/m2.
    Type: Application
    Filed: February 21, 2018
    Publication date: January 23, 2020
    Inventors: Kazuaki Hosomi, Kouki Tomimura, Takefumi Nakako
  • Publication number: 20190247956
    Abstract: A vacuum insulation panel manufacturing method that makes it possible to manufacture low-cost, high-performance vacuum insulation panels, and a vacuum insulation panel are provided.
    Type: Application
    Filed: May 31, 2017
    Publication date: August 15, 2019
    Inventors: Tsutomu AZUMA, Hirohisa MISHIMA, Takefumi NAKAKO
  • Publication number: 20190242120
    Abstract: A vacuum insulation panel for a construction, a car or an electric appliance includes a vacuum insulation panel in which a core material made of inorganic fibers is wrapped with an outer packaging material made of a stainless steel plate, and an inner space of the outer packaging material wrapping the core material is in a vacuum state, wherein a water content of the core material is 0.05 wt % or less, the surface roughness Ra of the inner space-side surface of the outer packaging material is 0.2 ?m or less, and a peripheral part of the outer packaging material is sealed by welding in a state in which the pressure of the inner space of the outer packaging material is 1 Pa or less.
    Type: Application
    Filed: September 1, 2017
    Publication date: August 8, 2019
    Inventors: Tsutomu AZUMA, Hirohisa MISHIMA, Takefumi NAKAKO, Seiichi KUBONIWA
  • Publication number: 20190193201
    Abstract: A vacuum insulation panel manufacturing method that makes it possible to manufacture low-cost, high-performance vacuum insulation panels, and a vacuum insulation panel are provided.
    Type: Application
    Filed: December 21, 2018
    Publication date: June 27, 2019
    Inventors: Tsutomu AZUMA, Hirohisa MISHIMA, Takefumi NAKAKO
  • Publication number: 20190143450
    Abstract: A vacuum insulation panel manufacturing method that makes it possible to manufacture low-cost, high-performance vacuum insulation panels, and a vacuum insulation panel are provided.
    Type: Application
    Filed: May 31, 2017
    Publication date: May 16, 2019
    Inventors: Tsutomu AZUMA, Hirohisa MISHIMA, Takefumi NAKAKO
  • Publication number: 20190134731
    Abstract: The present invention provides a method for producing a TIG-welded stainless steel tube without adding H2 to a shielding gas, while inhibiting generation of a weld defect. The method is a method for producing a TIG-welded stainless steel tube and includes the steps of bending a stainless steel strip in a width direction so as to butt both edges against each other and TIG-welding the both edges thus butted. A pulse waveform of a pulse frequency of 40 Hz to 300 Hz is used as a current waveform of a welding power source.
    Type: Application
    Filed: June 2, 2017
    Publication date: May 9, 2019
    Inventors: Takefumi Nakako, Tomokazu Nobutoki, Hiroshi Asada
  • Publication number: 20180354049
    Abstract: Hot dip Zn-based alloy coated steel sheets (1, 1?) are arc-weld in such a way that (a) a current waveform is a pulsed current waveform in which (i) a peak current and a base current alternate with each other at a pulse period of 1 ms to 50 ms and (ii) an average welding current is 100 A to 350 A and (b) an average welding voltage is 20 V to 35 V. Each of the hot dip Zn-based alloy coated steel sheets (1, 1?) includes a coating layer that contains Zn as a main component and that contains Al at a concentration of 1.0% by mass to 22.0% by mass, and has a coating weight W of 15 g/m2 to 250 g/m2.
    Type: Application
    Filed: February 2, 2016
    Publication date: December 13, 2018
    Applicant: Nisshin Steel Co., Ltd.
    Inventors: Kazuaki Hosomi, Tomokazu Nobutoki, Takefumi Nakako
  • Patent number: 10144091
    Abstract: A welded portion shape of a cross-section perpendicular to the shaped steel longitudinal direction is set to satisfy a>0 mm, b>0 mm, c?0.14 Tw, d?0 mm, e?0 mm, a+d?2 mm and b+e?2 mm; where a is a front melting width of the web material (on the laser beam irradiation side), b is a rear melting width of the web material (on the laser beam non-irradiation side), c is a maximum weld penetration depth, in a plate pressure direction, into the flange material, d is a front melting width of the flange material (on the laser beam irradiation side), e is a rear melting width of the flange material (on the laser beam non-irradiation side), and Tw is the plate thickness of the web material.
    Type: Grant
    Filed: July 26, 2012
    Date of Patent: December 4, 2018
    Assignee: NISSHIN STEEL CO., LTD.
    Inventors: Yasuhiro Sakurada, Takefumi Nakako, Hiroshi Asada
  • Patent number: 9993896
    Abstract: A laser welding method for welding materials having different thicknesses includes abutting two plates having different thicknesses such that one surface of the thin plate and one surface the thick plate are made flush with each other; and thereafter welding the plates by applying a laser beam to abutting surfaces thereof, wherein the laser beam is directed obliquely relative to an abutting end face of the thick plate, a target position of the laser beam is determined on the abutting end face of the thick plate, and a target position depth D on the abutting end face of the thick plate is determined based on the formula t/3?D?t where t is a thickness of the abutting end face of the thin plate.
    Type: Grant
    Filed: June 1, 2015
    Date of Patent: June 12, 2018
    Assignee: NISSHIN STEEL CO., LTD.
    Inventors: Kazuaki Hosomi, Kenji Ogawa, Takefumi Nakako, Keiji Yamamoto