Patents by Inventor Masao Yukumoto

Masao Yukumoto 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: 6273967
    Abstract: An amorphous alloy having a boron content of about 6 to 10 at %, cast into a plate, wherein the plate thickness is about 15 to 25 &mgr;m, and the surface roughness Ra0.8 of the plate is about 0.8 &mgr;m or less.
    Type: Grant
    Filed: January 29, 1997
    Date of Patent: August 14, 2001
    Assignee: Kawasaki Steel Corporation
    Inventors: Kensuke Matsuki, Fumio Kogiku, Nobuo Shiga, Masao Yukumoto
  • Patent number: 5833769
    Abstract: A wide amorphous alloy thin strip having a width of 70 mm or above and useful as an iron core of electric power transformers, composed of Fe--Si--B--C amorphous alloy. Dispersion of an amorphous structure in the width direction is prevented and deterioration of the strip properties is suppressed by adding Mn or by casting in an atmosphere containing a carbonic acid gas in an amount of about 40 vol % or more to thereby control strip surface roughness to a center line average surface roughness of about 0.7 .mu.m or less.
    Type: Grant
    Filed: October 7, 1996
    Date of Patent: November 10, 1998
    Assignee: Kawasaki Steel Corporation
    Inventors: Fumio Kogiku, Seiji Okabe, Kensuke Matsuki, Masao Yukumoto
  • Patent number: 5765625
    Abstract: A method and apparatus for manufacturing an amorphous metal ribbon provides the following: jetting a molten metal from a nozzle, which has a slit-shaped opening, to a cooling roll, which rotates at a high speed, so as to form a puddle on the cooling roll; and spreading the puddle for rapid solidification. Additionally, the present invention provides at a position upstream from the puddle in a direction opposite the direction of rotation of the cooling roll, cleaning the surface of the cooling roll by blowing carbon dioxide gas to which ultrasonic vibration is applied.
    Type: Grant
    Filed: December 4, 1996
    Date of Patent: June 16, 1998
    Assignee: Kawasaki Steel Corporation
    Inventors: Masao Yukumoto, Kensuke Matsuki, Nobuo Shiga, Hitoshi Ogo
  • Patent number: 5658397
    Abstract: An iron-based amorphous alloy thin strip for wound transformers has a composition expressed by a chemical formula:Fe.sub.a B.sub.b Si.sub.c Mn.sub.dwhere about 78.ltoreq.a.ltoreq. about 82 at %, about 8.ltoreq.b.ltoreq. about 15 at %, 4.ltoreq.c.ltoreq. about 14 at %, and about 0.2.ltoreq.d.ltoreq. about 1.0 at %. The ratio (building factor) of the iron loss of a wound core obtained from the above-described alloy thin strip to the iron loss of a single strip is about 1.5 or below.
    Type: Grant
    Filed: July 26, 1995
    Date of Patent: August 19, 1997
    Assignee: Kawasaki Steel Corporation
    Inventors: Fumio Kogiku, Masao Yukumoto, Kensuke Matsuki
  • Patent number: 5626690
    Abstract: A low boron amorphous alloy having excellent soft magnetic characteristics, composed of B: about 6-10 at %, Si: about 10-17 at %, P: about 0.02-2 at % and the balance Fe and incidental impurities. The invention lowers production costs because the content of expensive boron is reduced.
    Type: Grant
    Filed: August 28, 1995
    Date of Patent: May 6, 1997
    Assignee: Kawasaki Steel Corporation
    Inventors: Kensuke Matsuki, Masao Yukumoto, Fumio Kogiku
  • Patent number: 5522947
    Abstract: Disclosed are an amorphous iron based alloy having excellent magnetic characteristics as well as bendability and a method of manufacturing the amorphous iron based alloy.The amorphous iron based alloy has a mean centerline Ra surface roughness of about 0.8 .mu.m or less and the formula Fe.sub.X B.sub.Y Si.sub.Z Mn.sub.a in approximate proportions wherein:75<X<82 at %7<Y<15 at %,7<Z<17 at %, and0.2<a<0.5 at %.The method of manufacturing the amorphous iron based alloy comprises quenching and solidifying a molten alloy having the formula Fe.sub.X B.sub.Y Si.sub.Z Mn.sub.a in approximate proportions wherein:75<X<82 at %7<Y<15 at %,7<Z<17 at %, and0.2<a<0.5 at %, andeffecting the quenching and solidifying steps in a Co.sub.2. atmosphere containing H.sub.2 in an amount of about 1-4% by volume.
    Type: Grant
    Filed: April 24, 1995
    Date of Patent: June 4, 1996
    Assignee: Kawasaki Steel Corporation
    Inventors: Fumio Kogiku, Masao Yukumoto, Seiji Okabe
  • Patent number: 5499673
    Abstract: A continuous thin metal strip formed by quenching on a single quenching roll is separated from the quenching roll and conveyed along a fly path to a coiling system directly or via pinch rolls. The path along which the thin metal strip flies is stabilized by a jet of a fluid jetted from a slit and biased to flow along a convex curved surface, whereby the time until the strip is taken up or nipped by the pinch rolls is shortened.
    Type: Grant
    Filed: October 13, 1994
    Date of Patent: March 19, 1996
    Assignee: Kawasaki Steel Corporation
    Inventors: Nobuo Shiga, Tomohiro Marui, Kiyoshi Shibuya, Toru Sato, Michiharu Ozawa, Masao Yukumoto
  • Patent number: 5466304
    Abstract: Disclosed are an amorphous iron based alloy having excellent magnetic characteristics as well as bendability and a method of manufacturing the amorphous iron based alloy. The amorphous iron based alloy has a mean centerline Ra surface roughness of about 0.8 .mu.m or less and the formula Fe.sub.X B.sub.Y Si.sub.Z Mn.sub.a in approximate proportions wherein:75.ltoreq.X.ltoreq.82 at %7.ltoreq.Y.ltoreq.15 at %,7.ltoreq.Z.ltoreq.17 at %, and0.2.ltoreq.a.ltoreq.0.5 at %.The method of manufacturing the amorphous iron based alloy comprises quenching and solidifying a molten alloy having the formula Fe.sub.X B.sub.Y Si.sub.Z Mn.sub.a in approximate proportions wherein:75.ltoreq.X.ltoreq.82 at %7.ltoreq.Y.ltoreq.15 at %,7.ltoreq.Z.ltoreq.17 at %, and0.2.ltoreq.a.ltoreq.0.5 at %, andeffecting the quenching and solidifying steps in a Co.sub.2 atmosphere containing H.sub.2 in an amount of about 1-4% by volume.
    Type: Grant
    Filed: November 22, 1994
    Date of Patent: November 14, 1995
    Assignee: Kawasaki Steel Corporation
    Inventors: Fumio Kogiku, Masao Yukumoto, Seiji Okabe
  • Patent number: 5456308
    Abstract: A method and apparatus for manufacturing a thin amorphous metal strip. Molten metal is injected onto a single cooling roll rotating at high speed. A gas flow impeding wall is disposed adjacent to the surface of a cooling roll and extends across the body of the cooling roll. The wall is located upstream of the molten metal injection nozzle. CO.sub.2 gas is jetted along one surface of the gas insulating wall which faces the molten metal injection nozzle and toward the surface of the cooling roll. An atmosphere rich in CO.sub.2 gas is maintained adjacent the roll surface just upstream of the molten metal injection nozzle.
    Type: Grant
    Filed: February 8, 1994
    Date of Patent: October 10, 1995
    Assignee: Kawasaki Steel Corporation
    Inventors: Masao Yukumoto, Hiroshi Yamane, Seiji Okabe, Masanao Midorikawa, Kenzo Ohsu
  • Patent number: 5392837
    Abstract: Apparatus separates a thin metal strip produced from a molten metal from a surface of a cooling roll by rapidly solidifying using a single roll method and conveys and guides the separated thin strip downstream. A separation/tensioning/guiding unit is positioned adjacent the cooling roll to separate tension and guide the rapidly solidified thin strip, which unit includes a cooperating doctor blade in pressure contact with the cooling roll. A suction conveyor is provided downstream of the separation/tensioning/guiding unit.
    Type: Grant
    Filed: September 14, 1993
    Date of Patent: February 28, 1995
    Assignee: Kawasaki Steel Corporation
    Inventors: Masao Yukumoto, Michiharu Ozawa, Kiyoshi Shibuya, Saburo Moriwaki, Toru Sato
  • Patent number: 5160390
    Abstract: A rapidly solidified Fe-Cr-Al alloy foil having excellent anti-oxidation properties, the foil essentially consisting of Cr: about 5 to 30 wt %, Al: about 2 to 15 wt %, Si: about 1.5 to 3 wt %, and REM (Y, Ce, La, Pr, Nd): about 0.07 to 2.0 wt %, the balance being Fe and impurities. The foil may further contain about 0.001 to 0.5 wt % of at least one element selected from the group consisting of Ti, Nb, Zr and V. The foil has a grain size of not more than about 10 .mu.m. Preferably, the rapidly solidified alloy foil has a thickness of about 20 to 200 .mu.m.
    Type: Grant
    Filed: September 10, 1991
    Date of Patent: November 3, 1992
    Assignee: Kawasaki Steel Corporation
    Inventors: Masao Yukumoto, Michiharu Ozawa, Kazuhide Ishii, Hiroshi Shimizu
  • Patent number: 5010947
    Abstract: Each cooling roll has parallel grooves formed in the peripheral surface thereof so as to extend in a direction which crosses the direction of the roll axis. The grooves on one of the cooling rolls are at a phase difference from the grooves on the other cooling roll. The grooves are arranged at a pitch of 0.05 to 3.0 mm and each of the grooves has a width of 0.01 to 1.0 mm and a depth of 0.03 to 0.5 mm.
    Type: Grant
    Filed: February 23, 1990
    Date of Patent: April 30, 1991
    Assignee: Kawasaki Steel Corporation
    Inventors: Masao Yukumoto, Michiharu Ozawa, Hiroshi Yamane
  • Patent number: 4964583
    Abstract: A method and an apparatus for transporting a rapidly quenched ribbon from a cooling roll to a winding reel by a pinch roll are disclosed. The pinch roll comprises a brush roll and a solid roll for transporting the ribbon such as to maintain an adequate tension in the ribbon without any transversal displacement and breakdown of ribbon. The tension is controlled within a range of 2.about.8 kgf by adjusting at least one of an amount of pressing of the brush roll against the solid roll, a pressing force on the brush roll and a ratio between circumferential speeds of the pinch roll and the cooling roll.
    Type: Grant
    Filed: November 15, 1988
    Date of Patent: October 23, 1990
    Assignee: Kawasaki Steel Corporation
    Inventors: Masao Yukumoto, Kiyoshi Shibuya, Nobuyuki Morito, Teruo Hiramatsu
  • Patent number: 4951736
    Abstract: A cooling roll for producing quenched thin metal tape from molten metal by the twin-roll method. The roll is made of copper or copper alloy, and the roll surface is covered with a first layer of nickel plating 0.2 to 0.6 mm thick and a second layer of chromium plating 0.02 to 0.05 mm thick. The roll has the surface which does not suffer from deformation, seizure, winding, roughening, wear, and cracking. Thus the roll can produce quenched thin metal tape with a smooth surface in a stable manner for a long time.
    Type: Grant
    Filed: July 12, 1989
    Date of Patent: August 28, 1990
    Assignee: Kawasaki Steel Corporation
    Inventors: Masao Yukumoto, Michiharu Ozawa, Takahiro Kan
  • Patent number: 4754804
    Abstract: A rapidly solidified metallic tape is produced by continuously pouring molten metal into a casting space defined among a pair of cooling members and a pair of keep members each disposed close to side edge faces of the cooling rolls to rapidly solidify it. In this method, a solidification shell of molten metal produced on the keep member is continuously moved in a direction opposite to the pouring direction to eliminate to exterior from the system. In the apparatus for practicing the method, the keep member comprises a fixed side plate, a side roll rotatably arranged along a guide groove formed in the central and lower portion of the side plate, a driving means for the rotation of the side roll in a direction opposite to the pouring direction and a means for removing solidification shell from the surface of the side plate.
    Type: Grant
    Filed: October 13, 1987
    Date of Patent: July 5, 1988
    Assignee: Kawasaki Steel Corporation
    Inventors: Masao Yukumoto, Michiharu Ozawa
  • Patent number: 4546814
    Abstract: A process and an apparatus for producing rapidly solidified metallic tapes by a double-roll system are disclosed, wherein molten metal is poured into a kissing region defined between a fixed cooling roll and a movable cooling roll through a nozzle located thereabove and rapidly solidified at the kissing region to form a metallic tape. In this case, pushing forces added to the movable cooling roll by hydraulic cylinders at driving and operational sides are controlled by adding to or subtracting from a standard pushing force an adjusting quantity of the pushing force as a function of a difference between a roll gap at the driving side and a roll gap at the operational side.
    Type: Grant
    Filed: May 23, 1983
    Date of Patent: October 15, 1985
    Assignee: Kawasaki Steel Corporation
    Inventors: Kiyoshi Shibuya, Masao Yukumoto, Takahiro Kan, Yo Ito