Patents by Inventor Hitoshi Kitagawa

Hitoshi Kitagawa 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: 11125090
    Abstract: A first-stage stationary vane of a gas turbine includes: a vane portion including a pressure surface and a suction surface; a shroud wall portion which connects to an end portion of the vane portion and which forms a flow passage wall; a pressure-surface side fillet portion disposed on a corner portion formed by the pressure surface and a wall surface of the shroud wall portion; and a suction-surface side fillet portion disposed on a corner portion formed by the suction surface and the wall surface of the shroud wall portion. The pressure-surface side fillet portion and the suction-surface side fillet portion are separated at a leading-edge side of the vane portion so as not to connect to each other.
    Type: Grant
    Filed: September 5, 2019
    Date of Patent: September 21, 2021
    Assignee: MITSUBISHI POWER, LTD.
    Inventors: Yasuo Miyahisa, Satoshi Hada, Susumu Wakazono, Hitoshi Kitagawa, Takashi Hiyama
  • Patent number: 10938177
    Abstract: To provide a two-dimensional photonic crystal surface emitting laser capable of improving characteristics of light to be emitted, in particular, optical output power. The two-dimensional photonic crystal surface emitting laser includes: a two-dimensional photonic crystal including a plate-shaped base member and modified refractive index regions where the modified refractive index regions have a refractive index different from that of the plate-shaped base member and are two-dimensionally and periodically arranged in the base member; an active layer provided on one side of the two-dimensional photonic crystal; and a first electrode and a second electrode provided sandwiching the two-dimensional photonic crystal and the active layer for supplying current to the active layer, where the second electrode covers a region equal to or wider than the first electrode.
    Type: Grant
    Filed: September 27, 2019
    Date of Patent: March 2, 2021
    Assignees: KYOTO UNIVERSITY, ROHM CO., LTD., HAMAMATSU PHOTONICS K.K., MITSUBISHI ELECTRIC CORPORATION
    Inventors: Susumu Noda, Hitoshi Kitagawa, Yong Liang, Akiyoshi Watanabe, Kazuyoshi Hirose
  • Patent number: 10738640
    Abstract: A shroud (22) comprises shroud bodies (22) fixed to blade tips of blades (18) mounted to a rotor body to extend in a radial direction, the shroud bodies (22) being disposed adjacent to one another in a circumferential direction, wherein each of the shroud bodies (22) includes a circumferential end surface (27, 28) that includes an abutting end surface where adjacent shroud bodies (22) abut, and an opposing surface (34) where adjacent shroud bodies (22) face one another with a clearance (32) therebetween, the opposing surface (34) being contiguous with the abutting end surface; and an outer surface (24) that includes a radially outward protruding protrusion (40) formed to extend along the opposing surface (34).
    Type: Grant
    Filed: March 11, 2015
    Date of Patent: August 11, 2020
    Assignee: MITSUBISHI HEAVY INDUSTRIES, LTD.
    Inventors: Hitoshi Kitagawa, Takashi Hiyama, Daigo Fujimura
  • Publication number: 20200200033
    Abstract: A turbo machine includes a casing in which fluid flows; turbine blades arranged side by side in a circumferential direction with respect to a rotational shaft rotatably provided in the casing; a ring segment forming an inner surface of the casing; a seal fin provided as an extension at a tip end part of each turbine blade and facing the ring segment; and a seal member through which the turbo machine faces the seal fin, the seal member having a first inner surface that accepts contact of the seal fin. The ring segment has a second inner surface incrementally enlarging toward a downstream side in an axial direction of the rotational shaft. The first and second inner surfaces are connected with each other without a step between the inner surfaces on the downstream side of the first inner surface in the axial direction.
    Type: Application
    Filed: July 9, 2018
    Publication date: June 25, 2020
    Inventors: Hitoshi KITAGAWA, Daigo FUJIMURA
  • Patent number: 10641118
    Abstract: A sealing apparatus includes a sealing portion configured to be positioned between a platform of a turbine blade and an inner shroud of a turbine vane of a turbine, and an acoustic damper having a closed space portion which is configured to communicate, via an opening, with a disc cavity configured to be positioned between the turbine blade and the turbine vane.
    Type: Grant
    Filed: December 22, 2015
    Date of Patent: May 5, 2020
    Assignee: MITSUBISHI HEAVY INDUSTRIES, LTD.
    Inventors: Kazufumi Ikeda, Hitoshi Kitagawa, Masato Araki, Yoshiyuki Okabe
  • Publication number: 20200109638
    Abstract: A gas turbine includes a plurality of first-stage stator vanes arranged in a circumferential direction, the first-stage stator vanes each including a vane surface having a pressure surface and a suction surface, a first combustor disposed on a suction surface side of one of the first-stage stator vanes, the first combustor having a first combustor outlet which includes a first side wall portion extending along a radial direction, and a second combustor disposed on a pressure surface side of the one of the first-stage stator vanes and adjacent to the first combustor in the circumferential direction. The one of the first-stage stator vanes satisfies 0.05??y/P?0.25, where ?y is a protruding amount of the suction surface from the inner wall surface of the first side wall portion to the circumferential direction, and P is an arrangement pitch of the first-stage stator vanes in the circumferential direction.
    Type: Application
    Filed: June 19, 2018
    Publication date: April 9, 2020
    Inventors: Tetsuya SHIMMYO, Shunsuke TORII, Koichiro IIDA, Hitoshi KITAGAWA, Kenji SATO, Kentaro TOKUYAMA
  • Publication number: 20200088047
    Abstract: A first-stage stationary vane of a gas turbine includes: a vane portion including a pressure surface and a suction surface; a shroud wall portion which connects to an end portion of the vane portion and which forms a flow passage wall; a pressure-surface side fillet portion disposed on a corner portion formed by the pressure surface and a wall surface of the shroud wall portion; and a suction-surface side fillet portion disposed on a corner portion formed by the suction surface and the wall surface of the shroud wall portion. The pressure-surface side fillet portion and the suction-surface side fillet portion are separated at a leading-edge side of the vane portion so as not to connect to each other.
    Type: Application
    Filed: September 5, 2019
    Publication date: March 19, 2020
    Applicant: Mitsubishi Hitachi Power Systems, Ltd.
    Inventors: Yasuo Miyahisa, Satoshi Hada, Susumu Wakazono, Hitoshi Kitagawa, Takashi Hiyama
  • Publication number: 20200028327
    Abstract: To provide a two-dimensional photonic crystal surface emitting laser capable of improving characteristics of light to be emitted, in particular, optical output power. The two-dimensional photonic crystal surface emitting laser includes: a two-dimensional photonic crystal including a plate-shaped base member and modified refractive index regions where the modified refractive index regions have a refractive index different from that of the plate-shaped base member and are two-dimensionally and periodically arranged in the base member; an active layer provided on one side of the two-dimensional photonic crystal; and a first electrode and a second electrode provided sandwiching the two-dimensional photonic crystal and the active layer for supplying current to the active layer, where the second electrode covers a region equal to or wider than the first electrode.
    Type: Application
    Filed: September 27, 2019
    Publication date: January 23, 2020
    Applicants: KYOTO UNIVERSITY, ROHM CO., LTD., HAMAMATSU PHOTONICS K.K., MITSUBISHI ELECTRIC CORPORATION
    Inventors: Susumu NODA, Hitoshi KITAGAWA, Yong LIANG, Akiyoshi WATANABE, Kazuyoshi HIROSE
  • Patent number: 10461501
    Abstract: To provide a two-dimensional photonic crystal surface emitting laser capable of improving characteristics of light to be emitted, in particular, optical output power.
    Type: Grant
    Filed: August 28, 2015
    Date of Patent: October 29, 2019
    Assignees: KYOTO UNIVERSITY, ROHM CO., LTD., HAMAMATSU PHOTONICS K.K., MITSUBISHI ELECTRIC CORPORATION
    Inventors: Susumu Noda, Hitoshi Kitagawa, Yong Liang, Akiyoshi Watanabe, Kazuyoshi Hirose
  • Patent number: 10389086
    Abstract: A two-dimensional photonic-crystal surface-emitting laser 10 includes: a two-dimensional photonic crystal (two-dimensional photonic crystal layer 12) including a plate-shaped base body 121 having a predetermined size in which modified refractive index areas 122 whose refractive index differs from the base body are periodically arranged in a two-dimensional pattern; an active layer 11 provided on one side of the two-dimensional photonic crystal; and first and second electrodes 15 and 16 facing each other across the two-dimensional photonic crystal and the active layer 11, for supplying an electric current to the active layer 11. The modified refractive index areas 122 are provided in such a manner that the in-plane occupancy of those areas 122 in the base body 121 decreases, or the lattice constant for those areas 122 increases, in the direction from an outer edge toward the center of a current passage region 21 which is a region where the electric current passes through the two-dimensional photonic crystal.
    Type: Grant
    Filed: August 25, 2016
    Date of Patent: August 20, 2019
    Assignees: KYOTO UNIVERSITY, ROHM CO., LTD., HAMAMATSU PHOTONICS K.K., MITSUBISHI ELECTRIC CORPORATION
    Inventors: Susumu Noda, Hitoshi Kitagawa, Yoshinori Tanaka
  • Publication number: 20190157836
    Abstract: A two-dimensional photonic crystal including a plate-shaped base body in which modified refractive index areas differs from the base body are periodically arranged in a two-dimensional pattern; an active layer provided on one side of the two-dimensional photonic crystal; and first and second electrodes facing each other across the two-dimensional photonic crystal and the active layer, for supplying an electric current to the active layer. The modified refractive index areas are provided in the in-plane occupancy of areas in the base body increases, or the lattice constant for those areas decreases, in the direction from an outer edge toward the center of a current passage region where the electric current passes through the two-dimensional photonic crystal. A stable laser oscillation can be obtained when temperature distribution is lower at the outer edge and higher at the center of the current passage region is formed within the two-dimensional photonic crystal.
    Type: Application
    Filed: August 25, 2016
    Publication date: May 23, 2019
    Applicants: KYOTO UNIVERSITY, ROHM CO., LTD., HAMAMATSU PHOTONICS K.K., MITSUBISHI ELECTRIC CORPORATION
    Inventors: Susumu NODA, Hitoshi KITAGAWA, Yoshinori TANAKA
  • Publication number: 20180073378
    Abstract: In a sealing apparatus for a gas turbine, a gas turbine, and an aircraft engine: a first sealing portion provided between a platform of a turbine blade and an inner shroud of a turbine vane of a turbine, and an acoustic damper having a closed space portion communicating, via an opening, with a disc cavity between the turbine blade and the turbine vane are provided. Accordingly, improvement in gas turbine efficiency is aimed for, by reduction of entrance of combustion gas into a turbine body being enabled with a small amount of purge air.
    Type: Application
    Filed: December 22, 2015
    Publication date: March 15, 2018
    Inventors: Kazufumi IKEDA, Hitoshi KITAGAWA, Masato ARAKI, Yoshiyuki OKABE
  • Patent number: 9845689
    Abstract: In a turbine exhaust structure and a gas turbine, a turbine casing (26) formed in an annular shape to constitute a combustion gas passage A is provided. An exhaust diffuser (31) formed in an annular shape to constitute a flue gas passage (B) is connected to the turbine casing (26) to constitute a configuration. By providing a pressure loss body (61) in the exhaust diffuser (31), efficient pressure recovery can be carried out, which improves turbine efficiency, thereby enabling improvement of the performance.
    Type: Grant
    Filed: March 22, 2012
    Date of Patent: December 19, 2017
    Assignee: MITSUBISHI HEAVY INDUSTRIES, LTD.
    Inventors: Hitoshi Kitagawa, Yasuro Sakamoto, Eisaku Ito
  • Publication number: 20170256911
    Abstract: A two-dimensional photonic crystal surface emitting laser capable of improving characteristics of light to be emitted, particularly optical output , which includes: a two-dimensional photonic crystal including a plate-shaped base member and modified refractive index regions where the modified refractive index regions have a refractive index different from that of the plate-shaped base member and are two-dimensionally and periodically arranged in the base member; an active layer provided on one side of the two-dimensional photonic crystal; and a first electrode and a second electrode provided sandwiching the two-dimensional photonic crystal and the active layer for supplying current to the active layer, where the second electrode covers a region equal to or wider than the first electrode, wherein the first electrode is formed so as to supply the current to the active layer with a different density depending on the in-plane position on the first electrode.
    Type: Application
    Filed: August 28, 2015
    Publication date: September 7, 2017
    Applicants: KYOTO UNIVERSITY, ROHM CO., LTD., HAMAMATSU PHOTONICS K.K., MITSUBISHI ELECTRIC CORPORATION
    Inventors: Susumu NODA, Hitoshi KITAGAWA, Yong LIANG, Akiyoshi WATANABE, Kazuyoshi HIROSE
  • Patent number: 9719354
    Abstract: A gas turbine burns the air compressed in a compressor with supplying fuel in a combustor so as to obtain rotary power by supplying the generated combustion gas to a turbine. The turbine includes turbine vane elements and turbine blade elements that are alternately positioned in a direction in which the combustion gas fluidizes in a turbine cylinder having a cylindrical shape, and a flue gas diffuser having a cylindrical shape and connected to a rear portion of the turbine cylinder. The turbine blade element includes a plurality of turbine blades positioned at equal intervals in the circumference direction. The turbine blades have a throat width on a longitudinal end side made larger than a throat width on a longitudinally intermediate portion side. This efficiently restores the pressure of the flue gas. This improves the efficiency of the turbine so that the performance can be improved.
    Type: Grant
    Filed: March 23, 2012
    Date of Patent: August 1, 2017
    Assignee: MITSUBISHI HITACHI POWER SYSTEMS, LTD.
    Inventors: Hitoshi Kitagawa, Yasuro Sakamoto, Eisaku Ito
  • Publication number: 20160369643
    Abstract: A shroud (22) comprises shroud bodies (22) fixed to blade tips of blades (18) mounted to a rotor body to extend in a radial direction, the shroud bodies (22) being disposed adjacent to one another in a circumferential direction, wherein each of the shroud bodies (22) includes a circumferential end surface (27, 28) that includes an abutting end surface where adjacent shroud bodies (22) abut, and an opposing surface (34) where adjacent shroud bodies (22) face one another with a clearance (32) therebetween, the opposing surface (34) being contiguous with the abutting end surface; and an outer surface (24) that includes a radially outward protruding protrusion (40) formed to extend along the opposing surface (34).
    Type: Application
    Filed: March 11, 2015
    Publication date: December 22, 2016
    Inventors: Hitoshi KITAGAWA, Takashi HIYAMA, Daigo FUJIMURA
  • Publication number: 20140041395
    Abstract: A gas turbine burns the air compressed in a compressor with supplying fuel in a combustor so as to obtain rotary power by supplying the generated combustion gas to a turbine. The turbine includes turbine vane elements and turbine blade elements that are alternately positioned in a direction in which the combustion gas fluidizes in a turbine cylinder having a cylindrical shape, and a flue gas diffuser having a cylindrical shape and connected to a rear portion of the turbine cylinder. The turbine blade element includes a plurality of turbine blades positioned at equal intervals in the circumference direction. The turbine blades have a throat width on a longitudinal end side made larger than a throat width on a longitudinally intermediate portion side. This efficiently restores the pressure of the flue gas. This improves the efficiency of the turbine so that the performance can be improved.
    Type: Application
    Filed: March 23, 2012
    Publication date: February 13, 2014
    Applicant: MITSUBISHI HEAVY INDUSTRIES, LTD.
    Inventors: Hitoshi Kitagawa, Yasuro Sakamoto, Eisaku Ito
  • Publication number: 20140023493
    Abstract: In a turbine exhaust structure and a gas turbine, a turbine casing (26) formed in an annular shape to constitute a combustion gas passage A is provided. An exhaust diffuser (31) formed in an annular shape to constitute a flue gas passage (B) is connected to the turbine casing (26) to constitute a configuration. By providing a pressure loss body (61) in the exhaust diffuser (31), efficient pressure recovery can be carried out, which improves turbine efficiency, thereby enabling improvement of the performance.
    Type: Application
    Filed: March 22, 2012
    Publication date: January 23, 2014
    Applicant: MITSUBISHI HEAVY INDUSTRIES, LTD.
    Inventors: Hitoshi Kitagawa, Yasuro Sakamoto, Eisaku Ito
  • Publication number: 20130224034
    Abstract: The blade body of the present invention is provided with a main body which has a dorsal face and a ventral face and also provided with a trailing edge portion which connects the dorsal face to the ventral face with a continuous curved face. The curved face of the trailing edge portion is gradually decreased in curvature radius from one of the dorsal face and the ventral face toward the rear end portion which is positioned most downstream in a direction at which a fluid flows, decreased to the greatest extent in curvature radius at the rear end portion, thereafter, gradually increased in curvature radius from the rear end portion toward the other of the dorsal face and the ventral face and arrives at the other of the dorsal face and the ventral face.
    Type: Application
    Filed: December 27, 2010
    Publication date: August 29, 2013
    Applicant: MITSUBISHI HEAVY INDUSTRIES, LTD.
    Inventors: Yasuro Sakamoto, Eisaku Ito, Hitoshi Kitagawa, Susumu Wakazono
  • Patent number: 8358895
    Abstract: Holes 12 are created in a slab-shaped body 11. On the first surface 131 of the body 11, the holes 12 are arranged at the lattice points of a triangular lattice 141. On the second surface 132, they are arranged at the lattice points 122 located at positions corresponding to the gravity center of a triangular lattice 141. Three air columns 12A obliquely extend from each lattice point 121 to the nearest three lattice points 122. Similarly, three air columns 12A obliquely extend from each lattice point 122 to the nearest three lattice points 121. In this construction, a periodic structural unit 16 consisting of three holes is created within the body 11 and this unit has a C3v-symmetrical shape at any section 14 parallel to the body 11. Due to this symmetry and the obliquely extending form of the air column 12A, a complete PBG with a large width is obtained. In one embodiment, a broad complete PBG whose width equals 15% of its middle value is obtained.
    Type: Grant
    Filed: March 20, 2007
    Date of Patent: January 22, 2013
    Assignees: Kyoto University, Alps Electric Co., Ltd.
    Inventors: Susumu Noda, Takashi Asano, Hitoshi Kitagawa