Patents by Inventor Takeshi Hikata

Takeshi Hikata 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: 6844064
    Abstract: A method of manufacturing an oxide superconducting wire which can manufacture the longest possible wire by connecting relatively short wires with each other and is capable of suppressing reduction of a critical current resulting from influence by strain when the wires connected with each other are bent, an oxide superconducting wire, a superconducting coil and a superconducting apparatus are provided. According to the method of manufacturing an oxide superconducting wire by superposing end portions of two oxide superconducting wires (1, 2) with each other thereby bonding the end portions and connecting the oxide superconducting wires with each other, a junction (L) formed by superposing the end portions with each other is so worked as to reduce the quantity of strain on an end of the junction (L) when the two oxide superconducting wires (1) and (2) connected with each other are bent.
    Type: Grant
    Filed: November 1, 2000
    Date of Patent: January 18, 2005
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Naoki Ayai, Ryosuke Hata, Hiromi Takei, Kazuhiko Hayashi, Takeshi Hikata
  • Patent number: 6828037
    Abstract: The invention provides a hydrogen permeable structure, which can effectively prevent peeling-off of a hydrogen permeable film and hence has higher durability, and a method of manufacturing the structure. The hydrogen permeable structure has a hydrogen permeable film formed on the surface of or inside a porous support, having a thickness of not more than 2 &mgr;m, and containing palladium (Pd). The hydrogen permeable film is formed on the surface of or inside the porous support by supplying a Pd-containing solution and a reducing feed material from opposite sides of the porous support.
    Type: Grant
    Filed: June 16, 2003
    Date of Patent: December 7, 2004
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Takashi Uemura, Kentaro Yoshida, Nobuyuki Okuda, Takeshi Hikata
  • Publication number: 20040037962
    Abstract: The invention provides a hydrogen permeable structure, which can effectively prevent peeling-off of a hydrogen permeable film and hence has higher durability, and a method of manufacturing the structure.
    Type: Application
    Filed: June 16, 2003
    Publication date: February 26, 2004
    Inventors: Takashi Uemura, Kentaro Yoshida, Nobuyuki Okuda, Takeshi Hikata
  • Patent number: 6641647
    Abstract: A hydrogen permeable structure includes a base material (1) including porous ceramic, and a hydrogen permeable film (2) formed on the base material (1), including palladium (Pd) and at least one element other than palladium and having an amount of hydrogen dissolution at a prescribed temperature smaller than that of palladium alone. The hydrogen permeable film (2) is formed on the surface of the porous ceramic base by a physical vapor deposition technique after any pin holes in the surface of the base have been filled with a porous oxide material.
    Type: Grant
    Filed: July 30, 2002
    Date of Patent: November 4, 2003
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Takashi Uemura, Kentaro Yoshida, Nobuyuki Okuda, Takeshi Hikata
  • Patent number: 6572683
    Abstract: A substance separation structure comprises a base material including a porous material having a continuous hole with an opening of the hole formed on at least one surface, a porous layer, formed to fill up the opening, having a hole smaller than the hole of the base material and a permeable membrane of not more than 1 &mgr;m in thickness formed on at least one surface of the base material formed with the porous layer to selectively permeate ions or neutral elements or molecules, and the surface roughness of at least one surface of the base material formed with the porous layer is not more than 0.3 &mgr;m in Rmax. The surface of the base material is polished with abrasive grains containing a porous material so that the opening of the base material can be filled up with the porous layer, and the permeable membrane is formed by ion plating.
    Type: Grant
    Filed: November 20, 2001
    Date of Patent: June 3, 2003
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Kentaro Yoshida, Takeshi Hikata, Nobuyuki Okuda, Takashi Uemura
  • Patent number: 6536096
    Abstract: Powder of not more than 1 &mgr;m in mean particle diameter is prepared to contain a mixture of superconducting phases mainly composed of 2212 phases of Bi—Sr—Ca—Cu or (Bi, Pb)—Sr—Ca—Cu and non-superconducting phases which is obtained by calcining and pulverizing raw material powder at least once, this powder is heat treated at a high temperature and thereafter coated with a metal to prepare a round wire by deformation processing, thereafter a tape type or flat type wire is prepared by deformation processing, then the wire is heat treated under conditions for allowing phase transformation of the 2212 phases of main superconducting phases to 2223 phases with facilitation of grain growth, thereafter the as-formed 2223 phases are highly densified by deformation processing or pressurization, and the wire is again heat treated so that the 2223 phases are strongly bonded with each other and the non-superconducting phases are finely dispersed.
    Type: Grant
    Filed: December 15, 1993
    Date of Patent: March 25, 2003
    Assignee: Sumitomo Electric Industries, Ltd
    Inventors: Kenichi Sato, Nobuhiro Shibuta, Hidehito Mukai, Takeshi Hikata, Munetsugu Ueyama, Takeshi Kato
  • Publication number: 20030000387
    Abstract: A hydrogen permeable structure includes a base material (1) including porous ceramic, and a hydrogen permeable film (2) formed on the base material (1), including palladium (Pd) and at least one element other than palladium and having an amount of hydrogen dissolution at a prescribed temperature smaller than that of palladium alone. The hydrogen permeable film (2) is formed on the surface of the base material (1) including the porous ceramic by a physical vapor deposition technique.
    Type: Application
    Filed: July 30, 2002
    Publication date: January 2, 2003
    Inventors: Takashi Uemura, Kentaro Yoshida, Nobuyuki Okuda, Takeshi Hikata
  • Publication number: 20020062738
    Abstract: A substance separation structure comprises a base material including a porous material having a continuous hole with an opening of the hole formed on at least one surface, a porous layer, formed to fill up the opening, having a hole smaller than the hole of the base material and a permeable membrane of not more than 1 &mgr;m in thickness formed on at least one surface of the base material formed with the porous layer to selectively permeate ions or neutral elements or molecules, and the surface roughness of at least one surface of the base material formed with the porous layer is not more than 0.3 &mgr;m in Rmax. The surface of the base material is polished with abrasive grains containing a porous material so that the opening of the base material can be filled up with the porous layer, and the permeable membrane is formed by ion plating.
    Type: Application
    Filed: November 20, 2001
    Publication date: May 30, 2002
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Kentaro Yoshida, Takeshi Hikata, Nobuyuki Okuda, Takashi Uemura
  • Publication number: 20020050053
    Abstract: Powder of not more than 1 &mgr;m in mean particle diameter is prepared to contain a mixture of superconducting phases mainly composed of 2212 phases of Bi—Sr—Ca—Cu or (Bi, Pb)—Sr—Ca—Cu and non-superconducting phases which is obtained by calcining and pulverizing raw material powder at least once, this powder is heat treated at a high temperature and thereafter coated with a metal to prepare a round wire by deformation processing, thereafter a tape type or flat type wire is prepared by deformation processing, then the wire is heat treated under conditions for allowing phase transformation of the 2212 phases of main superconducting phases to 2223 phases with facilitation of grain growth, thereafter the as-formed 2223 phases are highly densified by deformation processing or pressurization, and the wire is again heat treated so that the 2223 phases are strongly bonded with each other and the non-superconducting phases are finely dispersed.
    Type: Application
    Filed: December 15, 1993
    Publication date: May 2, 2002
    Inventors: KENICHI SATO, NOBUHIRO SHIBUTA, HIDEHITO MUKAI, TAKESHI HIKATA, MUNETSUGU UEYAMA, TAKESHI KATO
  • Patent number: 6357105
    Abstract: An oxide superconducting wire of an anisotropic oxide superconductor comprises a core part of the wire and a superconducting layer enclosing the core part so that specific crystal axes of the oxide superconductor are oriented toward the core part. A method of producing a wire of an anisotropic oxide superconductor comprises the steps of arranging a metal sheath around a metal rod for forming a core part of the wire and charging powder of the oxide superconductor in a clearance between the metal sheath and the metal rod for preparing a composite material, and plastically working the composite material so that the metal sheath is larger in reduction of area than the metal rod.
    Type: Grant
    Filed: October 14, 1997
    Date of Patent: March 19, 2002
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Takeshi Hikata, Hidehito Mukai, Kenichi Sato
  • Publication number: 20020022389
    Abstract: A conductor of the present invention has a conductive DLC film formed on a conductive base. A conductive DLC film is formed on a conductive base and is supported by a conical spring electrode to be in contact with the conductive DLC film. Thus, a conductor is obtained which has good wear resistance and oxidation resistance and which is suitable for bringing conductive parts into contact.
    Type: Application
    Filed: July 12, 2001
    Publication date: February 21, 2002
    Inventors: Takeshi Hikata, Nobuyuki Okuda, Koichi Sogabe, Shosaku Yamanaka
  • Publication number: 20020006512
    Abstract: An electrode for plating of one example of a corrosion-resistant conductive member of the present invention includes a base formed of stainless steel or the like, a first conductive film of an electrochemically noble material formed on the base, and a second conductive film of an electrochemically base material formed on the first conductive film. The second conductive film is of a material containing carbon. Thus, a corrosion-resistant conductive member is provided which has good corrosion resistance and which can be inexpensively manufactured.
    Type: Application
    Filed: July 2, 2001
    Publication date: January 17, 2002
    Inventors: Takeshi Hikata, Nobuyuki Okuda, Takashi Uemura, Koichi Sogabe, Shosaku Yamanaka
  • Patent number: 6276048
    Abstract: A method of producing a Bi—Pb—Sr—Ca—Cu oxide superconductor by thermally treating raw material comprises steps of performing first plastic deformation on the raw material, performing first heat treatment on the material being subjected to the first plastic deformation, performing second plastic deformation on the material being subjected to the first heat treatment, and performing second heat treatment on the material being subjected to the second plastic deformation.
    Type: Grant
    Filed: November 12, 1996
    Date of Patent: August 21, 2001
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Takeshi Hikata, Ken-ichi Sato, Hidehito Mukai, Nobuhiro Shibuta, Kazuya Ohmatsu, Masayuki Nagata, Satoshi Takano, Yoshikado Hosoda, Hajime Hitotsuyanagi, Maumi Kawashima
  • Patent number: 5910222
    Abstract: In a bismuth oxide superconductor having a composition of Bi--Sr--Ca--Cu or (Bi,Pb)--Sr--Ca--Cu and being covered with a metal sheath, the a-b plane of a 2223 phase, which is a 110 K phase, is oriented along the longitudinal direction as a matrix, while a dispersed superconducting phase mainly consisting of a 2212 phase, which is a 80 K phase, and/or non-superconducting phases is dispersed along the a-b plane in the 2223 phase, so that a magnetic field property of its critical current density is extremely improved. In order to prepare such a bismuth oxide superconductor, performed are the steps of preparing raw material which is based on a 2223 composition in. Bi--Sr--Ca--Cu or (Bi,Pb)--Sr--Ca--Cu in relation to blending/composition, consisting as a superconducting phase of mainly a 2212 phase and non-superconducting phases in relation to the crystal structure, covering the raw material with a metal sheath, and performing deformation processing and heat treatment on the composite.
    Type: Grant
    Filed: May 19, 1997
    Date of Patent: June 8, 1999
    Assignee: Sumitomo Electric Industries, Ltd
    Inventors: Kenichi Sato, Takeshi Hikata
  • Patent number: 5902774
    Abstract: A method of producing a tape-shaped superconducting wire is provided. The wire maintains a high critical temperature and a high critical current density along the overall length thereof. In this method, raw material powder for the oxide superconductor is first charged in a silver sheath and the sheath charged with the powder is subjected to plastic working to prepare a first flat type wire. On the other hand, a second wire consisting of a tape wire formed by coating a surface of a flat type wire having at least an outer surface consisting essentially of silver or a silver alloy with a metal oxide or ceramics, or a tape wire containing ceramics fibers and a binder dissipated by heat treatment is prepared. The first and second wires are layered with each other, and tightly wound in a pancake coil shape. The wires wound in the pancake coil shape are heat treated for sintering the oxide superconductor. After the heat treatment, the first wire is separated from the second wire.
    Type: Grant
    Filed: October 20, 1997
    Date of Patent: May 11, 1999
    Assignees: Sumitomo Electric Industries, Ltd., Research Development Corporation of Japan
    Inventors: Koji Muranaka, Kenichi Sato, Takeshi Hikata
  • Patent number: 5807808
    Abstract: In order to obtain a Bi--Sr--Ca--Cu--O or Bi--Pb--Sr--Ca--Cu--O oxide superconducting wire, raw material powder is pulverized to remove particles of non-superconducting phases having large particle sizes based on difference in particle size, and thereafter the raw material powder is covered with a sheath of silver or silver alloy, so that the sheath is subjected to plastic working and the raw material powder covered with the sheath is sintered.
    Type: Grant
    Filed: March 6, 1995
    Date of Patent: September 15, 1998
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Takeshi Hikata, Kenichi Sato
  • Patent number: 5670459
    Abstract: In a bismuth oxide superconductor having a composition of Bi-Sr-Ca-Cu or (Bi,Pb)-Sr-Ca-Cu and being covered with a metal sheath, the a-b plane of a 2223 phase, which is a 110 K phase, is oriented along the longitudinal direction as a matrix, while a dispersed superconducting phase mainly consisting of a 2212 phase, which is a 80 K phase, and/or non-superconducting phases is dispersed along the a-b plane in the 2223 phase, so that a magnetic field property of its critical current density is extremely improved. In order to prepare such a bismuth oxide superconductor, performed are the steps of preparing raw material which is based on a 2223 composition in Bi-Sr-Ca-Cu or (Bi,Pb)-Sr-Ca-Cu in relation to blending/composition, consisting as a superconducting phase of mainly a 2212 phase and non-superconducting phases in relation to the crystal structure, covering the raw material with a metal sheath, and performing deformation processing and heat treatment on the composite.
    Type: Grant
    Filed: August 1, 1994
    Date of Patent: September 23, 1997
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Kenichi Sato, Takeshi Hikata
  • Patent number: 5663120
    Abstract: In order to prevent expansion of a metal sheath which is heat treated in order to form an oxide high-temperature superconductor therein, the heat treatment temperature is held at a certain level in an intermediate stage of temperature rising in a step of heat treating the metal sheath after filling raw material for an oxide high-temperature superconductor into the metal sheath. After the heat treatment temperature is thus held at the certain level, the metal sheath is again heated to a target temperature. Preferably, the heat treatment temperature is held at a level which is selected in a range of at least 500.degree. C. and not more than 750.degree. C.
    Type: Grant
    Filed: September 29, 1994
    Date of Patent: September 2, 1997
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Takeshi Hikata, Kenichi Sato
  • Patent number: 5639714
    Abstract: A method of producing a Bi-Pb-Sr-Ca-Cu oxide superconductor by thermally treating raw material comprises steps of performing first plastic deformation on the raw material, performing first heat treatment on the material being subjected to the first plastic deformation, performing second plastic deformation on the material being subjected to the first heat treatment, and performing second heat treatment on the material being subjected to the second plastic deformation.
    Type: Grant
    Filed: June 2, 1995
    Date of Patent: June 17, 1997
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Takeshi Hikata, Ken-ichi Sato, Hidehito Mukai, Nobuhiro Shibuta, Kazuya Ohmatsu, Masayuki Nagata, Satoshi Takano, Yoshikado Hosoda, Hajime Hitotsuyanagi, Maumi Kawashima
  • Patent number: 5610123
    Abstract: In a method of preparing a bismuth oxide superconducting wire comprising the steps of filling raw material powder into a metal sheath, working the same into a wire by performing deformation processing in this state, and heat treating the wire, the raw material powder is heat treated before the step of working the raw material powder into a wire by performing deformation processing, so that the ratio of a 2212 phase, containing Bi or (Bi,Pb), Sr, Ca and Cu in composition ratios of about 2:2:1:2, to a 2223 phase, containing Bi or (Bi,Pb), Sr, Ca and Cu in composition ratios of about 2:2:2:3, is 75 to 90:10 to 25, in order to prepare a wire which is excellent in critical current density as well as in critical current.
    Type: Grant
    Filed: February 8, 1995
    Date of Patent: March 11, 1997
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Kenichi Sato, Takeshi Hikata, Munetsugu Ueyama