Patents by Inventor Hirokazu Tozawa

Hirokazu Tozawa 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: 6117389
    Abstract: Titanium killed steel sheets which are not troubled by nozzle clogging while they are produced in a continuous casting process, have few surface defects caused by cluster-type inclusions, and are highly rust resistant, and are formed from a melt of titanium killed steel that contains any one or two of Ca and metals REM in an amount of not smaller than 0.0005% by weight, and wherein the steel contains major oxide inclusions of any one or two of CaO and REM oxides in an amount of from about 5 to 50% by weight, Ti oxides in an amount of not larger than about 90% by weight, and Al.sub.2 O.sub.3 in an amount of not larger than about 70% by weight.
    Type: Grant
    Filed: September 24, 1998
    Date of Patent: September 12, 2000
    Assignee: Kawasaki Steel Corporation
    Inventors: Seiji Nabeshima, Hirokazu Tozawa, Kenichi Sorimachi
  • Patent number: 5579824
    Abstract: In a process of withdrawing castings while vertically oscillating a mold formed with long side walls and short side walls, the long side walls are moved apart from the castings by operating a hydraulic cylinder in the time zones for which the castings are applied with a large frictional force. On the contrary, the separated long side walls are made to move together to the casting in the other time zones for which the casting is not applied with the large frictional force. By repeating the separation and approaching of the long side walls, it is possible to obtain castings which are reduced in the depths of oscillation marks and suppressed in segregations at oscillation mark trough portions.
    Type: Grant
    Filed: February 16, 1996
    Date of Patent: December 3, 1996
    Assignee: Kawasaki Steel Corporation
    Inventors: Seiji Itoyama, Hirokazu Tozawa, Shuji Takeuchi, Kenichi Sorimachi
  • Patent number: 5381857
    Abstract: One or more streams of molten metal poured into a continuous casting mold are acted on magnetically by static magnetic fields, covering substantially the entire width of the casting mold, thereby reducing the speed of the molten metal streams from the immersion nozzle, unifying the flow profile of the molten metal in the mold, preventing trapping and accumulating of mold powders and inclusions into the cast products. Magnetic poles are provided which are at least as wide as or wider than the minimum width of the cast products and the iron core is arranged on the same face of the casting mold with mutually opposite polarities in the drawing direction. Even if casting conditions change from time to time, defects in final products made of the cast metal are substantially reduced.
    Type: Grant
    Filed: March 3, 1994
    Date of Patent: January 17, 1995
    Assignee: Kawasaki Steel Corporation
    Inventors: Hirokazu Tozawa, Shuji Takeuchi, Kenichi Sorimachi, Tetsuya Fujii, Noboru Yasukawa, Saburo Moriwaki, Mitsuru Sakurai, Makoto Aratani, Yoshiro Tomiyama, Takeshi Shiraishi
  • Patent number: 5350005
    Abstract: A control device for controlling mold oscillation in a continuous casting machine comprises a horizontal position detector, an open-close control device and hydraulic cylinders. The horizontal position detector is attached to a piston rod of the hydraulic cylinder for detecting an actual position of long-side copper plates of a mold. The open-close control device further comprises a reference position compensation circuit where a predetermined offset value is received. The reference position compensation circuit produces a compensation signal with which a target position of the long-side copper plates is modified. The open-close control device controls the hydraulic cylinders according to the compensation signal such that a deviation between the actual horizontal position and the target horizontal position of the long-side copper plates becomes equal to the offset value.
    Type: Grant
    Filed: May 21, 1993
    Date of Patent: September 27, 1994
    Assignees: Kawasaki Steel Corporation, Sumitomo Heavy Industries, Ltd.
    Inventors: Kenichi Sorimachi, Hirokazu Tozawa, Toshiaki Ochi, Yasuhito Itoh
  • Patent number: 5299627
    Abstract: Steel is continuously cast while adding a mold powder using a vertical continuous casting mold having two pairs of mold surfaces which form a casting cavity, wherein the surface temperature of the mold is kept at 700.degree. C. or more by forming the mold surfaces of a Ni-Cr alloy, and a mold powder having a solidifying point lower than the surface temperature is used so that the mold powder is maintained in a liquid-phase state.
    Type: Grant
    Filed: March 3, 1992
    Date of Patent: April 5, 1994
    Assignee: Kawasaki Steel Corporation
    Inventors: Kenichi Sorimachi, Hirokazu Tozawa, Seiji Itoyama, Shuji Takeuchi, Akira Yamauchi
  • Patent number: 4945975
    Abstract: A method of oscillating a mold of a vertical continuous caster of the type having a pair of longer side frames and a pair of shorter side frames. The mold is oscillated vertically during the casting. A pair of mold walls, e.g., the longer side frames, are moved towards and away from the cast metal in synchronization with a vertical oscillation of the mold, so as to control the condition for supplying a mold powder into the gap between the mold walls and the cast metal.
    Type: Grant
    Filed: November 30, 1989
    Date of Patent: August 7, 1990
    Assignee: Kawasaki Steel Corporation
    Inventors: Kenichi Sorimachi, Hirokazu Tozawa, Tetsuya Fujii, Seiji Itoyama, Yuji Miki
  • Patent number: 4825935
    Abstract: In order to securely hold a moving belt of a continuous casting device against selective movable side walls, a first group of rotatable control rods which are disposed in a first supply header and an adjacent exhaust header are arranged to produce narrow high pressure zones in the film defined between the cooling pad in which the header are formed and the moving belt. These zones can be selectively moved to juxtapose the side walls when the gap between the walls is adjusted. A second group of rotatable control rods which are disposed in second and third supply headers selectively heat the side edges of the belt which are relatively cool as compared with the center section which is exposed to molten metal. As the side walls are moved apart the width of the edge sections which are exposed to pre-heated coolant can be reduced and the amount of normal temperature coolant applied thereto also increased.
    Type: Grant
    Filed: December 9, 1987
    Date of Patent: May 2, 1989
    Assignee: Kawasaki Steel Corporation
    Inventors: Hirokazu Tozawa, Nagayasu Bessho, Tetsuya Fujii, Saburo Moriwaki, Noboru Yasukawa, Tomoaki Kimura
  • Patent number: 4759400
    Abstract: A belt type cast sheet continuous caster of the type comprises a pair of opposed circulatorily movable belts, a pair of opposed side plates arranged along opposite side edge portions of the movable belts, coolers which each have numerous water feed openings and water discharge openings opened to the movable belt and are arranged behind the respective movable belts, and movable partition plates which are placed in respective cooling headers and each connected to driving means for moving the partition plates in a width direction of a cast sheet. A casting space is defined by the movable belt and the side plates.
    Type: Grant
    Filed: October 1, 1986
    Date of Patent: July 26, 1988
    Assignees: Kawasaki Steel Corporation, Hitachi, Ltd.
    Inventors: Nagayasu Bessho, Hirokazu Tozawa, Tetsuya Fujii, Tsutomu Nozaki, Saburo Moriwaki, Noboru Yasukawa, Masaaki Kuga, Michio Suzuki, Nozomu Tamura, Tomoaki Kimura