Patents by Inventor Yasuo Kamitsuma

Yasuo Kamitsuma 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: 5478220
    Abstract: The present invention provides an Al--Si based sintered alloy of high strength and high ductility, a method for production thereof and use thereof. The alloy comprises 1-45% of Si, 0.1-20% of an element of Group IIIa, 0.01-5% of at least one element of Groups IVa and Va, the balance of substantially Al. This alloy can further contain at least one of 0.01-5% of Cu, 0.01-5% of Mg, 2.0% or less of Fe, 1.5% or less of Mn and 1.5% or less of Co and the oxygen content is reduced to 0.15% or less by sintering under vacuum. The present invention is applied to automobile parts such as a piston and scroll compressors. The alloy has a tensile strength of about 40 kg/mm.sup.2 or higher and an elongation of 1.5% or more at 150.degree. C.
    Type: Grant
    Filed: September 23, 1994
    Date of Patent: December 26, 1995
    Assignees: Hitachi, Ltd., Hitachi Powdered Metals Co., Ltd.
    Inventors: Yasuo Kamitsuma, Yusaku Nakagawa, Mitsuo Chigasaki, Tadashi Iizuka, Kooichi Inaba, Keiichi Nakamura, Masaki Minabe, Tsuyoshi Kagaya
  • Patent number: 5387272
    Abstract: The present invention provides an Al-Si based sintered alloy of high strength and high ductility, a method for production thereof and use thereof. The alloy comprises 1-45% of Si, 0.1-20% of an element of Group IIIa, 0.01-5% of at least one element of Groups IVa and Va, the balance of substantially Al. This alloy can further contain at least one of 0.01-5% of Cu, 0.01-5% of Mg, 2.0% or less of Fe, 1.5% or less of Mn and 1.5% or less of Co and the oxygen content is reduced to 0.15% or less by sintering under vacuum. The present invention is applied to automobile parts such as a piston and scroll compressors. The alloy has a tensile strength of about 40 kg/mm.sup.2 or higher and an elongation of 1.5% or more at 150.degree. C.
    Type: Grant
    Filed: April 8, 1992
    Date of Patent: February 7, 1995
    Assignees: Hitachi, Ltd., Hitachi Powdered Metals Company, Limited
    Inventors: Yasuo Kamitsuma, Yusaku Nakagawa, Mitsuo Chigasaki, Tadashi Iizuka, Kooichi Inaba, Keiichi Nakamura, Masaki Minabe, Tsuyoshi Kagaya
  • Patent number: 5346667
    Abstract: A method of manufacturing sintered Al-Si series alloy parts having complex configurations such as scroll shaped parts wherein Al-Si series alloy powder solidified via rapid cooling prepared by adding effective components such as Si, Cu, Mg, Fe, Mn, Zr and Ce to Al is compression molded, the molded body is sintered by heating via an electrical current conduction in a form of a plasma discharge and then the sintered body is worked by pressing, thereby the parts having complex configurations of light weight, high mechanical strength and toughness is manufactured with a simple installation and reduced processing manhours, and with a high efficiency and at a low cost.
    Type: Grant
    Filed: September 29, 1992
    Date of Patent: September 13, 1994
    Assignees: Hitachi, Ltd., Hitachi Powdered Metals Co., Ltd.
    Inventors: Yasuo Kamitsuma, Yusaku Nakagawa, Yoshihiro Kobayashi, Shoichi Nakashima, Tadashi Iizuka, Keiichi Nakamura, Hideo Shikata
  • Patent number: 5087181
    Abstract: A sliding structure such as a compressor and etc. comprising a member made of an iron base material and another member having a porous ceramic layer slidably contacted with the iron base member, wherein the surface portion of the iron base member has both a porous oxide film containing tri-iron tetroxide as a main constituent, and an oxynitride layer formed under the oxide film.
    Type: Grant
    Filed: March 6, 1990
    Date of Patent: February 11, 1992
    Assignee: Hitachi, Ltd.
    Inventors: Yasuo Kamitsuma, Isao Ishi, Yusaku Nakagawa, Noriyuki Ohnaka, Tadashi Iizuka, Kazushi Fukuda
  • Patent number: 4944663
    Abstract: A sliding member of an iron-based non-porous material, such as vane, of a rotary compressor has a sliding surface processed by a surface treatment in which the surface is subjected to oxidizing and nitriding to form an oxidized and nitrided layer thereon. The surface is then subjected to a steam-treatment in which water is caused to react with components of the oxidized and nitrided layer to form a layer of oxidized iron of a porous network structure disposed outwardly of the oxidized and nitrided layer. The oxidized iron layer is composed mainly of tri-iron tetroxide and softer than the oxidized and nitrided layer.
    Type: Grant
    Filed: April 19, 1989
    Date of Patent: July 31, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Tadashi Iizuka, Kazushi Fukuda, Shin Ishihara, Yasuo Kamitsuma, Yusaku Nakagawa