Patents by Inventor Mitsuo Chigasaki

Mitsuo Chigasaki 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).

  • Publication number: 20070081916
    Abstract: A powder of an alloy containing a compound is enclosed in a cylindrical container, hot isostatic press and/or hot extrusion are applied in that state, and compound is isolated by these workings in order to metallically bond the powders with each other. When the metallic part is inserted into the container or the metallic part has a cylindrical shape, the container is formed of a material which can be the metallic part. Then, machining is applied in order to produce a metallic part having on a surface thereof an alloyed layer containing the dispersed compound particles. The metallic parts having on a surface thereof an alloyed layer containing dispersed compound particles can be produced without using a joining method such as welding.
    Type: Application
    Filed: December 8, 2006
    Publication date: April 12, 2007
    Inventors: Mitsuo Chigasaki, Jiro Kuniya, Yoshihisa Kiyotoki, Akira Sakamoto, Satoshi Furusawa
  • Patent number: 6959916
    Abstract: A valve which is cobalt-free excellent in wear resistance and seizure resistance manufactured by forming valve seats for a valve disc and a valve body with a nickel base alloy in which silicide particles or boride particles of small particle size are finely dispersed, and the valve seat is bonded to the valve disc or the valve body by way of an insert material comprising a nickel base alloy of a lower melting point by transient liquid phase diffusion bonding.
    Type: Grant
    Filed: November 6, 2002
    Date of Patent: November 1, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Mitsuo Chigasaki, Shizuo Matsushita, Jiro Kuniya, Yoshihisa Kiyotoki, Kikuo Takeshima, Akira Sakamoto, Yoshiteru Chiba
  • Patent number: 6896978
    Abstract: In the joint construction of cobalt-based alloy, a cobalt-based alloy layer 1, in which granular or massive eutectic carbide 2 disperses, is joined to a metal of a base metal 37 via an insert metal layer 36. For the joint construction of cobalt-based alloy, liquid phase diffusion bonding is performed at a temperature of 1100° C. for a retention time of 1 hour with an insert metal with a thickness of about 40 ?m being interposed between the base metal, which is S45C carbon steel, and a cobalt-based alloy material which has granular or massive eutectic carbide with a grain size not larger than 30 ?m in a matrix of cast structure and contains 1.03 wt % C, 29.73 wt % Cr, 3.86 wt % W, 2.59 wt % Ni, 2.67 wt % Fe, 0.59 wt % Si, and 0.07 wt % Mo, the balance substantially being Co. The cobalt-based alloy layer 1 after bonding contains granular or massive eutectic carbide.
    Type: Grant
    Filed: February 27, 2002
    Date of Patent: May 24, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Yoshihisa Kiyotoki, Mitsuo Chigasaki, Shizuo Matsushita, Jiro Kuniya, Takahiko Kato, Yoshiteru Chiba
  • Patent number: 6889957
    Abstract: In the joint construction of cobalt-based alloy, a cobalt-based alloy layer 1, in which granular or massive eutectic carbide 2 disperses, is joined to a metal of a base metal 37 via an insert metal layer 36. For the joint construction of cobalt-based alloy, liquid phase diffusion bonding is performed at a temperature of 1100° C. for a retention time of 1 hour with an insert metal with a thickness of about 40 ?m being interposed between the base metal, which is S45C carbon steel, and a cobalt-based alloy material which has granular or massive eutectic carbide with a grain size not larger than 30 ?m in a matrix of cast structure and contains 1.03 wt % C, 29.73 wt % Cr, 3.86 wt % W, 2.59 wt % Ni, 2.67 wt % Fe, 0.59 wt % Si, and 0.07 wt % Mo, the balance substantially being Co. The cobalt-based alloy layer 1 after bonding contains granular or massive eutectic carbide.
    Type: Grant
    Filed: October 16, 2002
    Date of Patent: May 10, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Yoshihisa Kiyotoki, Mitsuo Chigasaki, Shizuo Matsushita, Jiro Kuniya, Takahiko Kato, Yoshiteru Chiba
  • Patent number: 6886809
    Abstract: In the joint construction of cobalt-based alloy, a cobalt-based alloy layer 1, in which granular or massive eutectic carbide 2 disperses, is joined to a metal of a base metal 37 via an insert metal layer 36. For the joint construction of cobalt-based alloy, liquid phase diffusion bonding is performed at a temperature of 1100° C. for a retention time of 1 hour with an insert metal with a thickness of about 40 ?m being interposed between the base metal, which is S45C carbon steel, and a cobalt-based alloy material which has granular or massive eutectic carbide with a grain size not larger than 30 ?m in a matrix of cast structure and contains 1.03 wt % C, 29.73 wt % Cr, 3.86 wt % W, 2.59 wt % Ni, 2.67 wt % Fe, 0.59 wt % Si, and 0.07 wt % Mo, the balance substantially being Co. The cobalt-based alloy layer 1 after bonding contains granular or massive eutectic carbide.
    Type: Grant
    Filed: September 25, 2003
    Date of Patent: May 3, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Yoshihisa Kiyotoki, Mitsuo Chigasaki, Shizuo Matsushita, Jiro Kuniya, Takahiko Kato, Yoshiteru Chiba
  • Publication number: 20040247477
    Abstract: A powder of an alloy containing a compound is enclosed in a cylindrical container, hot isostatic press and/or hot extrusion are applied in that state, and compound is isolated by these workings in order to metallically bond the powders with each other. When the metallic part is inserted into the container or the metallic part has a cylindrical shape, the container is formed of a material which can be the metallic part. Then, machining is applied in order to produce a metallic part having on a surface thereof an alloyed layer containing the dispersed compound particles.
    Type: Application
    Filed: June 2, 2004
    Publication date: December 9, 2004
    Inventors: Mitsuo Chigasaki, Jiro Kuniya, Yoshihisa Kiyotoki, Akira Sakamoto, Satoshi Furusawa
  • Publication number: 20040056231
    Abstract: In the joint construction of cobalt-based alloy, a cobalt-based alloy layer 1, in which granular or massive eutectic carbide 2 disperses, is joined to a metal of a base metal 37 via an insert metal layer 36. For the joint construction of cobalt-based alloy, liquid phase diffusion bonding is performed at a temperature of 1100° C. for a retention time of 1 hour with an insert metal with a thickness of about 40 &mgr;m being interposed between the base metal, which is S45C carbon steel, and a cobalt-based alloy material which has granular or massive eutectic carbide with a grain size not larger than 30 &mgr;m in a matrix of cast structure and contains 1.03 wt % C, 29.73 wt % Cr, 3.86 wt % W, 2.59 wt % Ni, 2.67 wt % Fe, 0.59 wt % Si, and 0.07 wt % Mo, the balance substantially being Co. The cobalt-based alloy layer 1 after bonding contains granular or massive eutectic carbide.
    Type: Application
    Filed: September 25, 2003
    Publication date: March 25, 2004
    Applicant: Hitachi, Ltd.
    Inventors: Yoshihisa Kiyotoki, Mitsuo Chigasaki, Shizuo Matsushita, Jiro Kuniya, Takahiko Kato, Yoshiteru Chiba
  • Patent number: 6672330
    Abstract: A valve is characterized by excellent corrosion and wear resistance and maintainability due to use of a bonding corrosion and wear proof alloy containing non-continuously distributed eutectic carbide on the sliding portions of various types of apparatuses and valves by diffusion bonding. This serves to improve the maintainability of a thermal and nuclear power plant and to provide a nuclear power plant using recirculating water, which ensures excellent working safety, in particular. The corrosion and wear proof alloy is characterized in that network-formed eutectic carbide in the alloy containing the cast structure base metal and eutectic carbide is formed into(multiple) granules or lumps having a particle size of 30 microns or less so that said eutectic carbide is non-continuously distributed.
    Type: Grant
    Filed: February 5, 2001
    Date of Patent: January 6, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Mitsuo Chigasaki, Shizuo Matsushita, Jiro Kuniya, Yoshihisa Kiyotoki, Takahiko Kato, Yoshiteru Chiba
  • Publication number: 20030132415
    Abstract: A valve which is cobalt-free excellent in wear resistance and seizure resistance manufactured by forming valve seats for a valve disc and a valve body with a nickel base alloy in which silicide particles or boride particles of small particle size are finely dispersed, and the valve seat is bonded to the valve disc or the valve body by way of an insert material comprising a nickel base alloy of a lower melting point by transient liquid phase diffusion bonding.
    Type: Application
    Filed: November 6, 2002
    Publication date: July 17, 2003
    Applicant: Hitachi, Ltd.
    Inventors: Mitsuo Chigasaki, Shizuo Matsushita, Jiro Kuniya, Yoshihisa Kiyotoki, Kikuo Takeshima, Akira Sakamoto, Yoshiteru Chiba
  • Publication number: 20030129075
    Abstract: In the joint construction of cobalt-based alloy, a cobalt-based alloy layer 1, in which granular or massive eutectic carbide 2 disperses, is joined to a metal of a base metal 37 via an insert metal layer 36. For the joint construction of cobalt-based alloy, liquid phase diffusion bonding is performed at a temperature of 1100° C. for a retention time of 1 hour with an insert metal with a thickness of about 40 &mgr;m being interposed between the base metal, which is S45C carbon steel, and a cobalt-based alloy material which has granular or massive eutectic carbide with a grain size not larger than 30 &mgr;m in a matrix of cast structure and contains 1.03 wt % C, 29.73 wt % Cr, 3.86 wt % W, 2.59 wt % Ni, 2.67 wt % Fe, 0.59 wt % Si, and 0.07 wt % Mo, the balance substantially being Co. The cobalt-based alloy layer 1 after bonding contains granular or massive eutectic carbide.
    Type: Application
    Filed: October 16, 2002
    Publication date: July 10, 2003
    Applicant: Hitachi, Ltd.
    Inventors: Yoshihisa Kiyotoki, Mitsuo Chigasaki, Shizuo Matsushita, Jiro Kuniya, Takahiko Kato, Yoshiteru Chiba
  • Publication number: 20030026379
    Abstract: In the joint construction of cobalt-based alloy, a cobalt-based alloy layer 1, in which granular or massive eutectic carbide 2 disperses, is joined to a metal of a base metal 37 via an insert metal layer 36. For the joint construction of cobalt-based alloy, liquid phase diffusion bonding is performed at a temperature of 1100° C. for a retention time of 1 hour with an insert metal with a thickness of about 40 &mgr;m being interposed between the base metal, which is S45C carbon steel, and a cobalt-based alloy material which has granular or massive eutectic carbide with a grain size not larger than 30 &mgr;m in a matrix of cast structure and contains 1.03 wt % C, 29.73 wt % Cr, 3.86 wt % W, 2.59 wt % Ni, 2.67 wt % Fe, 0.59 wt % Si, and 0.07 wt % Mo, the balance substantially being Co. The cobalt-based alloy layer 1 after bonding contains granular or massive eutectic carbide.
    Type: Application
    Filed: February 27, 2002
    Publication date: February 6, 2003
    Inventors: Yoshihisa Kiyotoki, Mitsuo Chigasaki, Shizuo Matsushita, Jiro Kuniya, Takahiko Kato, Yoshiteru Chiba
  • Publication number: 20010017906
    Abstract: The object of the present invention is to provide a valve characterized by excellent corrosion and wear resistance and maintainability by bonding corrosion and wear proof alloy containing non-continuously distributed eutectic carbide to the sliding portions of various types of apparatuses and valves by diffusion bonding. Another object of the present invention is to improve the maintainability of a thermal and nuclear power plant and to provide a nuclear power plant comprising the recirculating water which ensures excellent working safety, in particular.
    Type: Application
    Filed: February 5, 2001
    Publication date: August 30, 2001
    Inventors: Mitsuo Chigasaki, Shizuo Matsushita, Jiro Kuniya, Yoshihisa Kiyotoki, Takahiko Kato, Yoshiteru Chiba
  • 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: 5296057
    Abstract: The object of the present invention is to provide an abrasion resistant aluminum bronze alloy for sliding members of various industrial machines.The abrasion resistant aluminum bronze alloy consists of Al: 7-12%, Mn: 1.5-5.5%, Si: 0.45-2.7%, respectively in weight, and the rest is substantially Cu, wherein metallic compound of Mn and Si is dispersed among said alloy structure, and elongation percentage is at least 5%.The abrasion resistant aluminum bronze alloy is superior to conventional aluminum bronze alloy (JIS-ALBC2) in seizure resistance and abrasion resistance by more than two times.
    Type: Grant
    Filed: September 21, 1992
    Date of Patent: March 22, 1994
    Assignee: Hitachi, Ltd.
    Inventors: Noboru Baba, Katsuhiko Komuro, Masateru Suwa, Mitsuo Chigasaki, Yozo Kumagai, Mashayoshi Kainuma, Masaru Sakakura
  • Patent number: 4912008
    Abstract: In an electrophotographic photosensitive device, which comprises an electroconductive support, a photoconductive layer provided thereon, and a surface protective layer provided on the photoconductive layer, the surface protective layer being made from a film having a density of localized states of not more than 5.times.10.sup.17 cm.sup.-3 and a higher dark resistance than that of the photoconductive layer, the surface protective layer is less susceptible to deterioration, adhesion to the photoconductive layer is enhanced, and thus the device has a prolonged life.
    Type: Grant
    Filed: May 31, 1988
    Date of Patent: March 27, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Megumi Naruse, Kunihiro Tamahashi, Mitsuo Chigasaki, Masanobu Hanazono
  • Patent number: 4804606
    Abstract: An electrophotographic sensitized body having a photoconductive layer comprising hydrogenated amorphous silicon on a substrate which comprises conductive material selected from the group consisting of A1, A1-Si (0.2-1.2 wt. %) - Mg (0.45-1.2 wt. %) alloy, super duralmine and extra super duralmine. Provided between the substrate and the photoconductive layer is a diffusion blocking layer 0.005-5 microns in thickness comprising a material selected from the group consisting of titanium nitride, tantalum nitride, hafnium nitride, platinum silicide, nickel silicide, palladium silicide, titanium silicide, hafnium silicide, tantalum silicide, tungsten silicide, vanadium silicide, niobium silicide, molybdenum silicide, zirconium silicide, tungsten carbide, titanium carbide, molybdenum carbide, hafnium carbide, vanadium carbide, niobium carbide, tantalum carbide and metallic chrome.
    Type: Grant
    Filed: September 2, 1987
    Date of Patent: February 14, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Toshiyuki Ohno, Kunihiro Tamahashi, Mitsuo Chigasaki
  • Patent number: 4791040
    Abstract: The photoconductive layer (3) has a triple-layer structure comprised of an upper layer (33) made of amorphous silicon containing germanium and carbon, a middle layer (32) made of amorphous silicon containing germanium, and a lower layer (31) made of amorphous silicon. The upper layer (33) formed between a surface layer (4) and the middle layer (32), and the lower layer (31) formed between the middle layer (32) and a barrier layer (2) serve to reduce the energy difference and the interfacial state between respective layers thus, high electrophotographic sensitivity for a longer wavelength light can be obtained, and sensitivity in the oscillation wavelength of a GaAlAs diode laser improves effectively.
    Type: Grant
    Filed: April 20, 1987
    Date of Patent: December 13, 1988
    Assignees: Hitachi Ltd., Hitachi Chemical Company, Ltd.
    Inventors: Makoto Fujikura, Toshiyuki Ohno, Shigeharu Onuma, Kunihiro Tamahashi, Mitsuo Chigasaki, Yasuo Shimamura
  • Patent number: 4692230
    Abstract: A method for forming a thin film wherein plural targets of different materials are alternately sputtered througth the switching of the electric powers supplied thereto, the particles produced from the sputtering are ionized and thereafter deposited on a substrate. This method provides an alloy thin film, compound thin film or multi-layer thin film of any composition and enhances adhesion among the particles. A sputtering device for practicing this method is also disclosed.
    Type: Grant
    Filed: April 15, 1986
    Date of Patent: September 8, 1987
    Assignee: Hitachi, Ltd.
    Inventors: Masayasu Nihei, Masateru Suwa, Mitsuo Chigasaki
  • Patent number: 4486245
    Abstract: A structure comprising a main body formed of a nickel base alloy, and a NiAl coating applied to the main body, wherein the NiAl coating includes a nickel rich NiAl layer and an aluminum rich NiAl layer and the thickness ratio of the nickel rich NiAl layer to the whole NiAl coating is in a range between 20 and 40%. A method of applying an aluminum coating to a nickel base alloy comprising the steps of forming an aluminide layer of Ni.sub.2 Al.sub.3 on the surface portion of the nickel base alloy by the diffusion and penetration of aluminum, and subjecting the alumide layer to heat treatment to change the aluminide layer to a monoaluminide layer and making the thickness ratio of a nickel rich NiAl layer to the whole monoaluminide layer be in the range between 20 and 40%.
    Type: Grant
    Filed: April 29, 1981
    Date of Patent: December 4, 1984
    Assignee: Hitachi, Ltd.
    Inventors: Mitsuo Chigasaki, Kiyoshi Otaka, Akira Okayama, Kenichi Onisawa, Ko Soeno