Patents by Inventor Kazumi Arakawa

Kazumi Arakawa 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: 4857488
    Abstract: A method for making a casting nozzle, includes mixing a main casting nozzle material 70-95% by weight and electrofused aggregates 5-30% by weight, the electrofused aggregates consisting essentially of ZrO.sub.2 30-60% by weight, Al.sub.2 O.sub.3 20-50% by weight, SiO.sub.2 10-20% by weight and SiC 5-40% by weight together with a binder, thereby to make a mixture, forming the mixture in the shape of a casting nozzle thereby to make a formed body, and sintering the formed body.
    Type: Grant
    Filed: February 28, 1987
    Date of Patent: August 15, 1989
    Assignee: Toshiba Ceramics Co., Ltd.
    Inventors: Yoshiro Aiba, Kazumi Arakawa, Takashi Watanabe, Kazuhide Kawai
  • Patent number: 4640336
    Abstract: A silicon aluminum oxynitride containing refractory for use in continuous casting is placed between a mold and a tundish and is formed by sintering an admixture of silicon nitride (Si.sub.3 N.sub.4), aluminum nitride (AlN), boron nitride(BN), and a mineral clay. The refractory further includes aluminum oxide(Al.sub.2 O.sub.3).
    Type: Grant
    Filed: September 24, 1985
    Date of Patent: February 3, 1987
    Assignees: Toshiba Ceramics Co., Ltd., Sumitomo Metal Industries, Ltd.
    Inventors: Kazumi Arakawa, Toshiyuki Hirao, Kenji Sugiura, Satoshi Kuroki, Sei Hiraki, Takao Suzuki, Ken Nakai
  • 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