Patents by Inventor Tsutomu Nagahata

Tsutomu Nagahata 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: 4632283
    Abstract: A molten metal discharging device comprising:a stationary plate adapted to be mounted at a bottom portion of a container accomodating molten metal, the stationary plate having a molten metal passage bore for permitting the molten metal from the container to be discharged therethrough, anda slide plate slidable along a lower face of the stationary plate and adapted to open or close the passage bore by being slidably displaced relative to the stationary plate, in whicha circumferential wall of the passage bore in the stationary plate is made of dense refractory material and the circumferential wall made of the dense refractory material has a plurality of gas supply holes therein for permitting a gas to be supplied into the passage borehas less fear that the passage bore thereof may be blocked by the solidification of the molten metal and/or deposition of metal oxides and has an improved resistance against corrosion by the molten metal.
    Type: Grant
    Filed: February 17, 1984
    Date of Patent: December 30, 1986
    Assignees: Toshiba Ceramics Co., Ltd., Sumitomo Metal Industries, Ltd.
    Inventors: Kazumi Arakawa, Masuo Sugie, Takashi Watanabe, Takumi Nishio, Toshio Kawamura, Tsutomu Nagahata, Takashi Matsushita
  • Patent number: 4583721
    Abstract: A molten metal discharging device including a stationary plate of refractory material and adapted to be mounted at a bottom portion of a container for accommodating molten metal, the stationary plate having a molten metal passage bore for permitting the molten metal from the container to be discharged therethrough, and a slide plate of refractory material slidable along a lower face of the stationary plate and adapted to open or close the passage bore by being slidably displaced relative to the stationary plate, wherein the stationary plate includes a stationary plate main body having the passage bore therein, at least a major part of the main body being made of porous refractory material, the stationary plate main body having a chamber around a circumferential wall part of the passage bore and a gas introduction hole communicated with the chamber for introducing a gas from outside into the chamber, the circumferential wall part having gas supply hole elements for supplying the gas therethrough from the chamb
    Type: Grant
    Filed: February 17, 1984
    Date of Patent: April 22, 1986
    Assignee: Toshiba Ceramics Co., Ltd.
    Inventors: Kazumi Arakawa, Masuo Sugie, Takashi Watanabe, Takumi Nishio, Toshio Kawamura, Tsutomu Nagahata, Takashi Matsushita
  • Patent number: 4325748
    Abstract: Steel plate having an excellent resistance to hydrogen induced cracking is obtained from a continuously cast slab having the following composition, C 0.01-0.30% by weight, Si 0.05-0.60% by weight, Mn 0.40-2.50% by weight, Sol Al 0.005-1.00% by weight, S 0.003% and lower by weight, the weight ratio of Ca/S is 2-10, the remainder being substantially Fe, through the steps of hot primary reduction rolling the cast slab, heating it at the temperature of 1200.degree. C. or higher for 10 hours or longer, and ordinary rolling it.
    Type: Grant
    Filed: March 27, 1980
    Date of Patent: April 20, 1982
    Assignee: Sumitomo Metal Industries, Ltd.
    Inventors: Hajime Nashiwa, Toshihiko Kawai, Muneyoshi Takeyama, Youzi Yamaguchi, Tsuneaki Kobayashi, Tsutomu Nagahata
  • Patent number: 4129439
    Abstract: Disclosed is a ferroalloy for refining molten steel, composed of, by weight, 5 to 40% Si, 40 to 80% Mn, 1 to 10% Al, and the remainder of Fe with inevitable amounts of impurities. The ferroalloy is suitable for use in deoxidizing molten steel and adjusting the composition thereof.
    Type: Grant
    Filed: September 30, 1976
    Date of Patent: December 12, 1978
    Assignee: Sumitomo Metal Industries, Ltd.
    Inventors: Hajime Nashiwa, Susumu Tsuzita, Tsutomu Nagahata