Patents by Inventor Ryo Hiraga

Ryo Hiraga 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: 6574966
    Abstract: A gas turbine for power generation operated at a turbine nozzle inlet temperature ranging from 1200 to 1650° C., which is improved to obtain a high heat efficiency by making disk blades and nozzles arranged in first to final stages from optimum materials and optimally cooling these disk blades and nozzles, and to obtain a combined power generation system using the gas turbine. The combined power generation system includes a highly efficient gas turbine operated at a turbine nozzle inlet combustion gas temperature ranging from 1200 to 1650° C., and a high pressure-intermediate pressure-low pressure integral type steam turbine operated at a steam inlet temperature of 530° C. or more, wherein the gas turbine is configured such that turbine blades, nozzles and disks are each cooled, and the blades and nozzles are each made from an Ni-based alloy having a single crystal or columnar crystal structure and disks are made from a martensite steel.
    Type: Grant
    Filed: April 18, 2002
    Date of Patent: June 10, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Kishio Hidaka, Shigeyoshi Nakamura, Yutaka Fukui, Masao Shiga, Ryo Hiraga, Hajime Toriya, Toshio Fujita
  • Patent number: 6546713
    Abstract: A gas turbine for power generation operated at a turbine nozzle inlet temperature ranging from 1200 to 1650° C., which is improved to obtain a high heat efficiency by making disk blades and nozzles arranged in first to final stages from optimum materials and optimally cooling these disk blades and nozzles, and to obtain a combined power generation system using the gas turbine. The combined power generation system includes a highly efficient gas turbine operated at a turbine nozzle inlet combustion gas temperature ranging from 1200 to 1650° C., and a high pressure-intermediate pressure-low pressure integral type steam turbine operated at a steam inlet temperature of 530° C. or more, wherein the gas turbine is configured such that turbine blades, nozzles and disks are each cooled, and the blades and nozzles are each made from an Ni-based alloy having a single crystal or columnar crystal structure and disks are made from a martensite steel.
    Type: Grant
    Filed: June 8, 2000
    Date of Patent: April 15, 2003
    Assignee: Hitachi, Ltd.
    Inventors: Kishio Hidaka, Shigeyoshi Nakamura, Yutaka Fukui, Masao Shiga, Ryo Hiraga, Hajime Toriya, Toshio Fujita
  • Publication number: 20020189229
    Abstract: An object of the present invention is to provide a gas turbine for power generation operated at a turbine nozzle inlet temperature ranging from 1200 to 1650° C., which is improved to obtain a high heat efficiency by making disk blades and nozzles arranged in first to final stages from optimum materials and optimally cooling these disk blades and nozzles, and a combined power generation system using the gas turbine.
    Type: Application
    Filed: April 18, 2002
    Publication date: December 19, 2002
    Inventors: Kishio Hidaka, Shigeyoshi Nakamura, Yutaka Fukui, Masao Shiga, Ryo Hiraga, Hajime Toriya, Toshio Fujita
  • Patent number: 6419453
    Abstract: The main object of the present invention is to provide a steam turbine rotor shaft whose high-temperature strength is excellent at a selected temperature of 650 degrees C. A steam turbine rotor shaft comprising 0.05% to 0.20% by weight of carbon, 0.20% or less by weight of silicon, 0.05% to 1.5% by weight of manganese, 0.01% to 1.0% by weight of nickel, 9.0% to 13.0% by weight of chrome, 0.05% to 2.0% by weight of molybdenum, 0.5% to 5.0% by weight of tungsten, 0.05% to 0.30% by weight of vanadium, 0.01% to 0.20% by weight of niobium, 0.5% to 10.0% by weight of cobalt, 0.01% to 0.1% by weight of nitrogen, 0.001% to 0.030% by weight of boron, 0.0005% to 0.006% by weight of aluminum, and the remaining parts substantially comprising iron and inevitable impurities.
    Type: Grant
    Filed: March 5, 2001
    Date of Patent: July 16, 2002
    Assignees: Hitachi, Ltd., The Japan Steel Works, Ltd.
    Inventors: Yutaka Fukui, Hiroyuki Doi, Masahiko Arai, Ryo Hiraga, Kenichiro Nomura, Toshio Fujita, Yasuhiko Tanaka
  • Publication number: 20010041137
    Abstract: The main object of the present invention is to provide a steam turbine rotor shaft whose high-temperature strength is excellent at a selected temperature of 650 degrees C.
    Type: Application
    Filed: March 5, 2001
    Publication date: November 15, 2001
    Inventors: Yutaka Fukui, Hiroyuki Doi, Masahiko Arai, Ryo Hiraga, Kenichiro Nomura, Toshio Fujita, Yasuhiko Tanaka
  • Patent number: 6248969
    Abstract: Disclosed is a vacuum circuit breaker including a small-sized electrode structure capable of reducing deformation with age thereby enhancing the reliability and a vacuum bulb and a vacuum bulb electrode used for the breaker. In the vacuum circuit breaker, each of a fixed electrode and a movable side electrode includes an arc electrode made from particles of a refractory metal material, a high conductive metal material and a low melting point metal; an electrode supporting portion, made from the high conductive metal material, for supporting the arc electrode; a back conductor having a diameter smaller than the electrode supporting portion; and an external side connecting portion having a diameter larger than that of the back conductor. The arc electrode is integrated with the electrode supporting portion, back conductor, and external side connecting portion by the high conductive metal material, preferably, by melting of the highly conductive metal material.
    Type: Grant
    Filed: September 17, 1998
    Date of Patent: June 19, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Katsuhiro Komuro, Yoshitaka Kojima, Noboru Baba, Ryo Hiraga, Toru Tanimizu, Yoshimi Hakamata, Katsumi Kuroda, Hitoshi Okabe, Shigeru Kikuchi
  • Patent number: 6182439
    Abstract: A combined cycle power generation system in which a generator is driven by a steam turbine and a gas turbine includes a steam turbine rotor having a mono-block rotor shaft with blades mounted thereon in multi-stages from a high pressure side to a low pressure side and a casing covering the rotor. An inlet temperature of steam to first stage blades is not less than 530° C. and the rotor shaft is made of a Ni—Cr—Mo—V low alloy steel of bainitic structure having a higher creep rupture strength at the high pressure side than at the low pressure side and a 538° C. and 105 h creep rupture strength not less than 12 kg/mm2 at a central portion, and having mounted thereon at the central portion, first stage blades at the high pressure side or FATT of not more than 20° C.
    Type: Grant
    Filed: August 31, 1999
    Date of Patent: February 6, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Masao Siga, Takeshi Onoda, Shigeyoshi Nakamura, Ryo Hiraga
  • Patent number: 6174132
    Abstract: A steam turbine in which principal components to be exposed to high temperatures are all made of ferritic steel, whereby the temperatures of main steam and reheat steam can be increased to 610-660 (° C.). The rotor shaft (23 in FIG. 1) of the steam turbine is made of ferritic forged steel whose 100,000-hour creep rupture strength is at least 15 (kg/mm2) at the service temperature of the rotor shaft. Likewise, the casing (18) is made of ferritic cast steel whose 100,000-hour creep rupture strength is at least 10 (kg/mm2). The steam turbine of high thermal efficiency can be applied to a steam-turbine power plant.
    Type: Grant
    Filed: May 11, 1998
    Date of Patent: January 16, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Masao Shiga, Ryo Hiraga, Takeshi Onoda, Nobuo Shimizu, Norio Yamada, Mitsuo Kuriyama, Kishio Hidaka, Shigeyoshi Nakamura, Yutaka Fukui, Toshio Fujita
  • Patent number: 6123504
    Abstract: A steam turbine includes a rotor shaft, movable blades assembled on the rotor shaft, fixed blades for guiding inflow of steam to the moving blades, and an inner casing for holding the fixed blades. The rotor shaft and at least a first stage of the movable blades are made of high-strength martensitic steel comprising 0.05-0.20(%) of C, at most 0.15(%) of Si, 0.3-0.7(%) of Mn, 9.5-13(%) of Cr, 0.3-0.7(%) of Ni, 0.05-0.35(%) of V, 0.02-0.15(%) of Nb, 0.01-0.06(%) of N, 0.05-0.5(%) of Mo, 1.0-3.5(%) of W, 2-10(%) of Co and 0.0005-0.03(%) of B and at least 78(%) of Fe (the percentages being given in terms of weight). The inner casings is made of martensitic cast steel comprising 0.06-0.16(%) of C, at most 0.5(%) of Si, at most 1(%) of Mn, 0.2-1.0(%) of Ni, 8-12(%) of Cr, 0.05-0.35(%) of V, 0.01-0.15(%) of Nb, 0.01-0.1(%) of N, at most 1.5% of Mo, 1-4(%) of W and 0.0005-0.03(%) of B and at least 85(%) of Fe (the percentages being given in terms of weight).
    Type: Grant
    Filed: February 21, 1995
    Date of Patent: September 26, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Masao Shiga, Ryo Hiraga, Takeshi Onoda, Nobuo Shimizu, Norio Yamada, Mitsuo Kuriyama, Kishio Hidaka, Shigeyoshi Nakamura, Yutaka Fukui, Toshio Fujita
  • Patent number: 6074169
    Abstract: A high and low pressure sides integrating steam turbine having high and low pressure sides integrating steam turbine blades, each made of a martensite steel including 8-13 wt % Cr, and having a blade length of 33 inches or more for 60 Hz power generation and 40 inches for 50 Hz power generation.
    Type: Grant
    Filed: September 22, 1997
    Date of Patent: June 13, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Masao Siga, Takeshi Onoda, Shigeyoshi Nakamura, Ryo Hiraga
  • Patent number: 5964091
    Abstract: A cylindrical gas turbine combustor, burning injected fuel and guiding the combustion gas to turbine nozzles, includes a cylindrical portion such as a combustor liner and a transition piece, exposed to the combustion gas, which is made of austenitic Fe base casting alloy, Ni base casting alloy or Co base casting alloy.
    Type: Grant
    Filed: July 9, 1996
    Date of Patent: October 12, 1999
    Assignee: Hitachi, Ltd.
    Inventors: Yutaka Fukui, Tetsuo Kashimura, Hideyo Kodama, Hiroyuki Doi, Ryo Hiraga
  • Patent number: 5961284
    Abstract: A steam turbine has main components such as rotor shaft exposed to high temperature and intermediate pressure, which are made of a ferritic steel and the main steam temperature and the re-heat steam temperature are 610.degree. C. to 660.degree. C., and a steam turbine power plant employs the turbine. Further, the rotating blades are made of only a martensitic steel or a combination of the martensitic steel and a Ni base alloy, the turbine rotor is made of a ferritic forged steel having a creep rupture strength at the operating temperature for 100 thousands hours of above 15 kg/mm.sup.2, and the casing is made of a ferritic cast steel having a creep rupture strength at the operating temperature for 100 thousands hours of above 10 kg/mm.sup.2.
    Type: Grant
    Filed: August 22, 1996
    Date of Patent: October 5, 1999
    Assignee: Hitachi, Ltd.
    Inventors: Mitsuo Kuriyama, Masao Shiga, Kishio Hidaka, Shigeyoshi Nakamura, Yutaka Fukui, Ryo Hiraga, Nobuo Shimizu, Masao Kawakami
  • Patent number: 5898177
    Abstract: A method of operating an electron microscope under a high temperature and the electron microscope are provided. The electron microscope can stably set and efficiently heat a sample to observe and measure high temperature physical properties such as phase transformation, phase transition and the like required for development of a heat resistant material. In the method of operating the electron microscope and the electron microscope, a sample to be observed is set so as to position at a central hole of a double spiral flat filament, the detachable heating stage is fixed to the heating holder using screws of a pivot, and the heating stage is tilted by vertical movement of a crank-shaped arm. The heating stage and the arm are insulated from each other by an insulating body, and current from a power source is conducted by a conductor wire to heat the filament.
    Type: Grant
    Filed: July 24, 1997
    Date of Patent: April 27, 1999
    Assignees: Hitachi, Ltd., Hitachi Instruments Engineering Co. Ltd.
    Inventors: Kishio Hidaka, Takeo Kamino, Toshie Yaguchi, Katsuhisa Usami, Takashi Aoyama, Shigeyoshi Nakamura, Ryo Hiraga, Masahiro Tomita
  • Patent number: 5749228
    Abstract: A steam turbine in which principal components to be exposed to high temperatures are all made of ferritic steel, whereby the temperatures of main steam and reheat steam can be increased to 610-660 (.degree.C.). The rotor shaft (23 in FIG. 1) of the steam turbine is made of ferritic forged steel whose 100,000-hour creep rupture strength is at least 15 (kg/mm.sup.2) at the service temperature of the rotor shaft. Likewise, the casing (18) is made of ferritic cast steel whose 100,000-hour creep rupture strength is at least 10 (kg/mm.sup.2). The steam turbine of high thermal efficiency can be applied to a steam-turbine power plant.
    Type: Grant
    Filed: May 30, 1995
    Date of Patent: May 12, 1998
    Assignee: Hitachi, Ltd.
    Inventors: Masao Shiga, Ryo Hiraga, Takeshi Onoda, Nobuo Shimizu, Norio Yamada, Mitsuo Kuriyama, Kishio Hidaka, Shigeyoshi Nakamura, Yutaka Fukui, Toshio Fujita
  • Patent number: 5008072
    Abstract: A heat resistant steel of the present invention contains 0.05 to 0.2 wt. % of C, less than 0.5 wt. % of Si, less than 0.6 wt. % of Mn, 8 to 13 wt. % of Cr, 1.5 to 3 wt. % of Mo, 2 to 3 wt. % of Ni, 0.05 to 0.3 wt. % of V, 0.02 to 0.2 wt. % in total of either or both of Nb and Ta, 0.02 to 0.1 wt. % of N and the balance substantially Fe. Since a gas turbine of the present invention is constituted by members, such as discs, blades, shafts and so forth, made of alloys of this kind, the gas turbine has a structure in which it is possible to achieve a high level of creep rupture strength and Charpy impact value.
    Type: Grant
    Filed: May 16, 1989
    Date of Patent: April 16, 1991
    Assignee: Hitachi, Ltd.
    Inventors: Masao Siga, Yutaka Fukui, Mitsuo Kuriyama, Soichi Kurosawa, Katsumi Iijima, Nobuyuki Iizuka, Yosimi Maeno, Shintaro Takahashi, Yasuo Watanabe, Ryo Hiraga
  • Patent number: 4933228
    Abstract: A thermosetting resin composition comprising a special poly(p-hydroxystyrene) derivative resin and a radical polymerization initiator, and if necessary an epoxy modified polybutadiene, can provide prepregs and laminates having a low dielectric constant, a shorter signalling delay time, good heat resistance and flame retardancy and thus being suitable for producing multilayer printed circuit boards.
    Type: Grant
    Filed: June 19, 1989
    Date of Patent: June 12, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Junichi Katagiri, Akira Nagai, Keiko Tawara, Akio Takahashi, Motoyo Wajima, Toshikazu Narahara, Ryo Hiraga
  • Patent number: 4912544
    Abstract: A corrosion-resistant aluminum electronic material comprising an alloy containing aluminum as the principal component and, in addition, a small amount of a noble metal, the content of said noble metal being equal to or less than that at the eutectic point having the primary crystal of aluminum. As the noble metal, there is contained at least one metal selected from Pt, Pd, Rh, Ir, Os, Ru, Au and Ag. Said electronic material is used for ball-bonding wire and distributing film in a semiconductor device, and the like.
    Type: Grant
    Filed: August 10, 1983
    Date of Patent: March 27, 1990
    Assignee: Hitachi, Ltd.
    Inventors: Jin Onuki, Masateru Suwa, Masahiro Koizumi, Osamu Asai, Katsumi Suzuki, Ryo Hiraga
  • Patent number: 4886858
    Abstract: A thermosetting resin composition comprising a special poly(p-hydroxystyrene) derivative resin and a radical polymerization initiator, and if necessary an epoxy modified polybutadiene, can provide prepregs and laminates having a low dielectric constant, a shorter signalling delay time, good heat resistance and flame retardancy and thus being suitable for producing multilayer printed circuit boards.
    Type: Grant
    Filed: February 17, 1987
    Date of Patent: December 12, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Junichi Katagiri, Akira Nagai, Keiko Tawara, Akio Takahashi, Motoyo Wajima, Toshikazu Narahara, Ryo Hiraga
  • Patent number: 4850187
    Abstract: A heat resistant steel of the present invention contains 0.05 to 0.2 wt. % of C, less than 0.5 wt. % of Si, less than 0.6 wt. % of Mn, 8 to 13 wt. % of Cr, 1.5 to 3 wt. % of Mo, 2 to 3 wt. % of Ni, 0.05 to 0.3 wt. % of V, 0.02 to 0.2 wt. % in total of either or both of Nb and Ta, 0.02 to 0.1 wt. % of N and the balance substantially Fe. Since a gas turbine of the present invention is constituted by members, such as discs, blades, shafts and so forth, made of alloys of this kind, the gas turbine has a structure in which it is possible to achieve a high level of creep rupture strength and Charpy impact value.
    Type: Grant
    Filed: February 4, 1987
    Date of Patent: July 25, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Masao Siga, Yutaka Fukui, Mitsuo Kuriyama, Soichi Kurosawa, Katsumi Iijima, Nobuyuki Iizuka, Yosimi Maeno, Shintaro Takahashi, Yasuo Watanabe, Ryo Hiraga
  • Patent number: 4775967
    Abstract: In the present invention, a micro Fresnel lens in the shape of a thin film is used. A lens driving member constructed of piezoelectric transducers or of magnets and coils is disposed around the lens. The focus of the lens is adjusted by controlling applied voltages to the piezoelectric transducers or the coils.
    Type: Grant
    Filed: October 11, 1985
    Date of Patent: October 4, 1988
    Assignee: Hitachi, Ltd.
    Inventors: Satoshi Shimada, Hiroshi Sasaki, Nobuyoshi Tsuboi, Hideki Nihei, Norifumi Miyamoto, Ito Tetsuo, Yoshio Sato, Atsumi Watanabe, Ryo Hiraga