Patents by Inventor Koki Nakada

Koki Nakada 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: 20220111464
    Abstract: A novel spot welding method for steel sheets and an aluminum alloy sheet, includes stacked sheet materials from a pair of opposing electrodes to join the sheet materials by resistance heating. The pair of opposing electrodes are in pressure contact with both outer surfaces of the sheet sets. The sheet sets include at least a first and second steel sheet, and an aluminum alloy sheet stacked in this order. A first energization step forms a molten pool between facing surfaces of the first and second steel sheets without melting the aluminum alloy sheet. A second energization step causes a melting reaction between facing surfaces of the second steel sheet and the aluminum alloy sheet. The first and second steel sheets are joined via a first nugget. The second steel sheet and the aluminum alloy sheet are joined via a second nugget including an intermetallic compound generated by the melting reaction.
    Type: Application
    Filed: July 12, 2021
    Publication date: April 14, 2022
    Applicants: KABUSHIKI KAISHA TOYOTA CHUO KENKYUSHO, TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Hideaki MATSUOKA, Takashi ASADA, Tatsuyuki AMAGO, Kyosuke IZUNO, Koki NAKADA, Tomohiko SEKIGUCHI, Shuhei OGURA
  • Publication number: 20210268597
    Abstract: A spot welding method includes a heating step of energizing an electrode in pressure contact with an Al alloy member to heat and melt a join part by resistance heating and a cooling step of cooling the join part after the heating step in a state in which the electrode is in pressure contact with the Al alloy member. The alloy is a wrought alloy of Mg: 0.2 to 1.2 mass %, Si: 0.4 to 1.5%, and Cu: 1.1% or less or a casting alloy of Si: 7 to 11% and Mg: 0.1 to 0.4% with respect to 100% as a whole. The cooling step includes a first cooling process performed with a reduced amount of input energy to the join part as compared with the heating step and a second cooling process performed after the first cooling process at a higher cooling rate than that in the first cooling process.
    Type: Application
    Filed: February 25, 2021
    Publication date: September 2, 2021
    Applicants: KABUSHIKI KAISHA TOYOTA CHUO KENKYUSHO, TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Hideaki MATSUOKA, Takanori NAKAGAKI, Kyosuke IZUNO, Koki NAKADA, Manabu OOGA
  • Publication number: 20190366479
    Abstract: In a laser welding method, generation of relatively large blow holes in a welding part is prevented while decrease in productivity is reduced. The laser welding method for lap welding, using a laser beam LB, of a plurality of metal plates and including an aluminum alloy cast plate includes: a melting path of scanning and irradiating circularly a superimposed part of the aluminum alloy plate and the aluminum alloy cast plate with a first laser beam LB1 to form a molten pool of the molten aluminum alloy plate and the molten aluminum alloy cast plate; and a stirring path of scanning and irradiating circularly the molten pool with a second laser beam LB2 having a scanning speed V2 faster than a scanning speed V1 of the first laser beam LB1 to stir the molten pool.
    Type: Application
    Filed: May 30, 2019
    Publication date: December 5, 2019
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Toru HIOKI, Shuhei OGURA, Atsushi KAWAKITA, Koki NAKADA, Takashi GOTO, Ryosuke KAWAI
  • Publication number: 20190329361
    Abstract: A laser welding method is provided to ensure a sufficient joining strength between metal plates by increasing the area of a joining region while preventing “burn through” of a molten metal. In the laser welding method by applying a laser beam to a surface of multiple metal plates superimposed on each other, a scanning locus with the laser beam is sequentially shifted from an inner circular scanning locus to an outer one in a predetermined joining region on the metal plates, and an emission interval is provided to temporally stop the metal-plate-surface irradiation when the scanning locus is shifted. Thus, every time the scanning locus is shifted, the molten metal due to the previous irradiation is cooled and increases its viscosity. Accordingly, the “burn through” is prevented regardless of increase of the area of the joining region, which results in a sufficient joining strength between the metal plates.
    Type: Application
    Filed: April 24, 2019
    Publication date: October 31, 2019
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Koki Nakada, Toru Hioki, Atsushi Kawakita, Shuhei Ogura, Takashi Goto