Patents by Inventor Hiroki Fukuno

Hiroki Fukuno 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: 6264426
    Abstract: In cooling a gas turbine stationary blade, steam and air are used as cooling media, the steam is recovered surely without leakage and used effectively, and the amount of air required for cooling is decreased to provide a margin for combustion air, by which the gas turbine efficiency is improved. A steam cooling section is provided at the rear from the blade leading edge, and an air cooling section is provided at the blade trailing edge. The steam cooling is effected by cooling the blade by the cooling steam flowing in the serpentine flow path having turbulators after impingement cooling of an outside shroud and by impingement-cooling an inside shroud during the cooling process, the cooling steam being led to a recovery section from the outside shroud. On the other hand, the air cooling section consists of an air flow path extending from the outside shroud to the inside shroud and slot cooling at the blade trailing edge.
    Type: Grant
    Filed: February 20, 1998
    Date of Patent: July 24, 2001
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventors: Hiroki Fukuno, Yasuoki Tomita, Kiyoshi Suenaga
  • Patent number: 6257830
    Abstract: In a steam cooling system proposed heretofore, high-pressure steam is supplied into an internal space of a blade for effecting cooling thereof with the high-pressure steam to thereby recover heat energy. This system however suffers from problems concerning the strength of the blade and the like. The present invention solves these problems and provides a gas-turbine blade which does not suffer from problems concerning the strength thereof nor problems concerning the flow of high-pressure steam. To this end, a coolant flow passage is formed within the blade extending in the longitudinal direction of the blade, and reinforcing ribs which interconnects a dorsal wall and a ventral wall of the blade is disposed within the coolant flow passage so as to extend in the flow direction of the coolant. Hence, the strength of the blade can be ensured without any obstacle to the flow of the coolant.
    Type: Grant
    Filed: June 2, 1999
    Date of Patent: July 10, 2001
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventors: Masaaki Matsuura, Kiyoshi Suenaga, Sunao Aoki, Kazuo Uematsu, Hiroki Fukuno, Yasuoki Tomita
  • Patent number: 6254346
    Abstract: The present invention relates to a gas turbine cooling moving blade and is applied to a large-sized blade for a high temperature so as to reduce its thickness and increase cooling efficiency and easily process the moving blade. A cavity is formed in the interior of the moving blade from the root portion to a shroud at the tip of the moving blade. Many turbulators are arranged in parallel with each other on an inner wall face of the moving blade. Cooling air from a turbine rotor enters the cavity formed within the moving blade from a cooling air inlet. This cooling air is dispersed and disturbed by the turbulators so that heat transfer is improved. Accordingly, the moving blade is efficiently cooled by the cooling air in comparison with a conventional cooling system having a multiplicity of holes. The cooling air is then discharged out of a cooling air outlet through air cooling holes of the shroud located at the tip of the moving blade.
    Type: Grant
    Filed: March 24, 1998
    Date of Patent: July 3, 2001
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventors: Hiroki Fukuno, Yasuoki Tomita, Kiyoshi Suenaga
  • Patent number: 6217279
    Abstract: A sealing device for a gas turbine stator blade, in which an outer shroud (32) is mounted by heat insulating rings (32a,32b) on a blade ring (50). The blade ring (50) has a first air hole (1), which communicates with a space (53), and a second air hole (51), which communicates with a seal tube (2). The seal tube (2) is inserted into the second air hole (51), and a spring (6) is arranged between a projection (4) of the tube (2) and a retaining portion (5) of the air hole (51) to removably secure the seal tube (2). Cooling air (54) flows through the first air hole (1) to cool the shrouds and the inside of a stator blade (31) until it is released from the trailing edge of the blade. The cooling air also flows into a cavity (36) so that a high pressure can be maintained without a pressure loss because the tube (2) is independent of the space (53) in the blade ring.
    Type: Grant
    Filed: February 10, 1999
    Date of Patent: April 17, 2001
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventors: Toshishige Ai, Masanori Yuri, Yasuoki Tomita, Kiyoshi Suenaga, Sunao Aoki, Hiroki Fukuno
  • Patent number: 6196791
    Abstract: In gas turbine cooled moving blade, a cooling air passage is made shortest and temperature elevation and pressure drop of the cooling air are suppressed. The cooling air passage (16) is bored in a turbine cylinder wall (15) located below a first stage stationary blade (11). The cooling air passage (16) communicates at one end (16a) with a turbine cylinder and at the other end (16b) with a space (13) between the stationary blade and the moving blade. The passage (16) is directed to an air inflow hole (6) provided in a shank portion (4) of a lower portion of a platform (2) of the moving blade (1). Cooling air is jetted from the cooling air passage (16) toward the air inflow hole (6) so as to flow into the shank portion (4) and then into the moving blade (1) for cooling thereof.
    Type: Grant
    Filed: December 23, 1998
    Date of Patent: March 6, 2001
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventors: Yasuoki Tomita, Hiroki Fukuno, Sunao Aoki, Kiyoshi Suenaga
  • Patent number: 6196798
    Abstract: A number of air-transpiration holes (4) are provided at a leading edge portion (2) of a cooled blade (1). Cooling air flowing through a cooling air passage (15) formed inside of the blade blows out to the blade surface of the leading edge portion (2) of the cooled blade (1) by way of the air-transpiration holes (4), to thereby shower-head cool the surface of the leading edge portion (2). The air-transpiration holes (4) are formed so as to extend substantially orthogonal to the leading edge surface of the cooled blade (1) such that the acute-angled portions are eliminated, whereby thermal stress is reduced and cracking is prevented.
    Type: Grant
    Filed: February 11, 1999
    Date of Patent: March 6, 2001
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventors: Hiroki Fukuno, Yasuoki Tomita, Shigeyuki Maeda, Yukihiro Hashimoto, Kiyoshi Suenaga
  • Patent number: 6190128
    Abstract: A cooled moving blade for a gas turbine which has a blade profile capable of more effectively reducing thermal stress in a blade base portion and, thus, preventing cracks from occurring. A moving blade (1) is fixedly secured to a platform (2). On the other hand, a cooling air passage (3) is formed in a serpentine pattern inside of the blade for cooling with cooling air. The moving blade (1) has a base portion of a profile formed by an elliptically curved surface (11) and a rectilinear surface portion (12), wherein the rectilinear surface portion (12) is provided at a hub portion of the blade where thermal stress is large. The cross-sectional area of the blade is increased by providing the rectilinear surface portion (12) The heat capacity is increased, compared with the conventional blade, due to the increased cross-sectional area of the blade. This, in turn, results in a decrease of the temperature difference due to the thermal stress.
    Type: Grant
    Filed: February 4, 1999
    Date of Patent: February 20, 2001
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventors: Hiroki Fukuno, Yasuoki Tomita, Shigeyuki Maeda, Yukihiro Hashimoto, Kiyoshi Suenaga
  • Patent number: 6189891
    Abstract: A gas turbine seal structure provided between end portions of a moving blade platform and a stationary blade inside shroud. The sealing performance of the seal structure is improved by increasing the resistance to the flow of air. A seal plate (21, 31) is mounted to an end portion of a platform (2, 2′) of the moving blade (1) and a seal portion is formed by seal fins (22, 32) and a honeycomb seal (16, 17) disposed on a lower surface of an end portion (12a, 12b) of an inside shroud (12) of a stationary blade (11). Sealing air from the stationary blade (11) produces a high temperature in a cavity (14) and flows into a space (18, 19), and also air leaking from the cooling air of the moving blade (1) is able to escape into a high temperature combustion gas passage through a seal portion. However, since the seal plate has three seal fins (22, 32) that are inclined in a direction so as to oppose the air flow, air resistance is increased and the flow of air into the combustion gas passage is prevented.
    Type: Grant
    Filed: February 24, 1998
    Date of Patent: February 20, 2001
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventors: Yasuoki Tomita, Kazuharu Hirokawa, Hiroki Fukuno, Kiyoshi Suenaga, Yukihiro Hashimoto, Eisaku Ito
  • Patent number: 6152690
    Abstract: A seal ring (1) securing inner shroud members (32) of stationary blades (31) is provided with arm portions (2, 3) projecting along lower surfaces of end portions of the inner shroud members (32). Honeycomb seals (4a, 4b) are mounted on the arm portions (2, 3), respectively. The honeycomb seal (4a) is disposed opposite fins (11a) provided on a rotor arm portion (11) of a platform (22) of a moving blade (21) so that a predetermined clearance (t) can be maintained between the honeycomb seal and the fins. On the other hand, the honeycomb seal (4b) is disposed opposite fins (14b) provided on a seal portion (14a) of a sealing plate (14) of the moving blade (21) so that a predetermined clearance (t) can be maintained between the honeycomb seal and the fins. The inner shroud members (32) undergo deformation after operation of the gas turbine.
    Type: Grant
    Filed: May 19, 1999
    Date of Patent: November 28, 2000
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventors: Yasuoki Tomita, Hiroki Fukuno, Katsunori Tanaka, Toshiaki Sano
  • Patent number: 6146098
    Abstract: A tip shroud for a moving blade that is made thin and light for use at a gas turbine downstream stage. Cooling air holes (13 to 16) having a slot shape, are formed in a tip shroud (11) of the moving blade (10). The cooling holes are opened in two side faces of the tip shroud to release the cooling air from the inside of the moving blade (10). In the upper face of the tip shroud 11, there are formed cooling air holes 20, which communicate with the higher pressure side in a combustion gas flow direction R to release the cooling air so that the cooling air flows from the higher pressure side to the lower pressure side so as to cool a high stress portion Y. A high stress portion X is likewise cooled with the cooling air coming from an adjoining moving blade. The slot shapes of the cooling air holes (13 to 16) allow the cooling air to flow widely, thereby cooling the face of the tip shroud (11), and the cooling air holes 20 cool the high stress portions X and Y effectively.
    Type: Grant
    Filed: February 22, 1999
    Date of Patent: November 14, 2000
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventors: Hiroki Fukuno, Yasuoki Tomita, Eisaku Ito
  • Patent number: 6142730
    Abstract: In a cooled gas turbine stationary blade, both steam cooling and air cooling are utilized to reduce the amount of cooling air. In the stationary blade having outer and inner shrouds 1, 21 and steam passages 10A, 10B, 10C, 10D and 10E which are communicated with each other and in which a sealing air feed tube 2 passes through a central portion thereof, steam covers 3, 4 are provided in the outer shroud 1, and steam S is introduced from a steam feed port 5. The steam S passes through serpentine passages 10A to 10E and is recovered from the steam outlet 12 after cooling the central portion of the outer shroud 1 by means of an impingement plate 8. A portion of the steam of the passage 10A is introduced from the impingement plate 25 to a steam sump 24 to cool the central portion of the inner shroud 21 and pass through the passage 10D to be recovered from the steam outlet port 12.
    Type: Grant
    Filed: December 21, 1998
    Date of Patent: November 7, 2000
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventors: Yasuoki Tomita, Kenichi Arase, Hiroki Fukuno, Hideki Murata, Kiyoshi Suenaga, Tsuyoshi Kitamura
  • Patent number: 6132173
    Abstract: A cooled platform for a gas turbine moving blade which enables the platform to be cooled when the moving blade is cooled by steam. The moving blade is provided with a plurality of steam passages. Steam is introduced from the steam passage at the trailing edge portion, flows in a serpentine passage composed of other steam passages to cool the blade, and flows out to a blade root portion from a base portion of the steam passage at the leading edge portion, being recovered. Part of steam flowing into the platform from the base portion of the steam passage at the trailing edge portion enters first and second steam passages in the platform. On one side, the steam passes through first, third, and fourth steam passages, and on the other hand, the steam passes through second, fifth, and sixth steam passages. The steam is recovered together with the steam having cooled the blade at the base portion of steam passage at the leading edge portion.
    Type: Grant
    Filed: March 17, 1998
    Date of Patent: October 17, 2000
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventors: Yasuoki Tomita, Hiroki Fukuno, Kenichi Arase, Toshiaki Sano
  • Patent number: 6099244
    Abstract: In the present invention, seal air passes through a tube extending in a stationary blade from an outside shroud to an inside shroud, flows into a cavity to keep the pressure in the cavity high so as to seal the high-temperature combustion gas, and is discharged to a passage. Part of cooling air flows into an air passage to cool the leading edge portion, passes through the peripheral portion of the inside shroud to cool the same, and is discharged to a passage. The remaining cooling air flows into a passage, passes through a serpentine cooling flow path consisting of air passages having turbulators, and is discharged through air cooling holes formed at the trailing edge. The cooling air passing through the passage at the leading edge portion cools the peripheral portion of the inside shroud as well as the leading edge portion of blade, by which the cooling efficiency is increased.
    Type: Grant
    Filed: March 11, 1998
    Date of Patent: August 8, 2000
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventors: Yasuoki Tomita, Hiroki Fukuno, Kiyoshi Suenaga
  • Patent number: 6089826
    Abstract: A gas turbine cooled blade has leading edge turbulators. A rounded tip portion of the leading edge portion cooling passage (3) is approximated by a triangular cooling passage (1) having orthogonal turbulators (11, 12) and a smoothly curved rear portion thereof of the leading edge portion cooling passage (3) is approximated by a square cooling passage 2 having oblique turbulators (13, 14).
    Type: Grant
    Filed: November 9, 1998
    Date of Patent: July 18, 2000
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventors: Yasuoki Tomita, Sunao Aoki, Hiroki Fukuno, Kiyoshi Suenaga
  • Patent number: 6089822
    Abstract: A gas turbine second stage stationary blade has cooling air passages of an inner shroud provided with enhanced cooling efficiency. In inner shroud 126, there are provided a leading edge passage 42 and trailing edge passage 44, both extending from blade portion and mutually separated by a rib 40, and impingement plates 83, 84 having a multiplicity of small holes 101. An opening portion 68 between the blade portion and the inner shroud 126 is closed by a bottom plate 150 and, together with a recess portion 100 at a bottom portion of the leading edge passage 42, connects to a passage 188 of a leading edge portion 41 via a passage 90'. Air from the trailing edge passage 44 flows into cavity 45 to be injected through the small holes 101 of the impingement plates 83, 84 for cooling of the central portion of the inner shroud 126 and is then discharged as air 60 through passages 92 of the trailing edge portion 43.
    Type: Grant
    Filed: October 28, 1998
    Date of Patent: July 18, 2000
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventor: Hiroki Fukuno
  • Patent number: 6086329
    Abstract: A seal plate at the platform portion of a gas turbine moving blade. The seal plate is inserted in a gap between the adjacent platforms at each end portion of a seal pin to prevent air from leaking to the outside. A groove is provided at each of four corners of the end portion of platform of the moving blade, and the seal plate is inserted to cover the gap so as to extend the end portions of the adjacent platforms, by which the gap between the platforms is blocked. A seal pin and end seal pins are inserted between the platforms to seal this portion. However, there is a gap at the end portions, so that cooling air leaks from the lower part of platform. Since the seal plate is inserted in the groove to block the gap, the sealing property is increased.
    Type: Grant
    Filed: March 11, 1998
    Date of Patent: July 11, 2000
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventors: Yasuoki Tomita, Hiroki Fukuno, Eisaku Ito
  • Patent number: 6079944
    Abstract: Seal plates for gas turbine stationary blade inner shrouds are made in a double cross type seal structure with a view to enhance sealing ability. Seal plates 1, 2 are mutually lapped and disposed in a turbine axial direction between inner shrouds 12 of stationary blades 11. End portion seal plate 5 is lapped on an end portion of the seal plate 2 and end portion seal plate 6 is lapped under an end portion of the seal plate 1. All these seal plates are fitted with their side end portions being inserted into groove 9a provided in the inner shrouds 12. Seal plates 3, 4 and seal plates 7, 8 engaged with the seal plates 3, 4 are also fitted between flange portions of the inner shrouds 12 with their side end portions being inserted into grooves 10a, 10b and grooves 9b, 9c, respectively.
    Type: Grant
    Filed: October 21, 1998
    Date of Patent: June 27, 2000
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventors: Yasuoki Tomita, Kenichi Arase, Naoki Hagi, Hiroki Fukuno
  • Patent number: 6077034
    Abstract: In the present disclosure, an air pipe extends through a stationary blade between outer and inner shrouds. Further, an air passage is directed to a lower portion of the stationary blade and is communicated with the air pipe so that a serpentine cooling passage is formed. The air enters a cavity from the air passage and is discharged to a gas passage through an air hole, a passage and a seal. Thus, the cavity is sealed at a high pressure. Cooling air is supplied from the air passage to a rotating blade through a cooling air hole, a cooling air chamber, a radial hole and a lower portion of a platform. The stationary blade is cooled by the air through the air passage. The cooling air can be supplied to the rotating blade at a low temperature and a high pressure as they are. Accordingly, the air can be also supplied to the rotating blade when a rotor is cooled by vapor.
    Type: Grant
    Filed: March 11, 1998
    Date of Patent: June 20, 2000
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventors: Yasuoki Tomita, Hiroki Fukuno, Yukihiro Hashimoto, Kiyoshi Suenaga
  • Patent number: 6039531
    Abstract: The present disclosure provides a gas turbine blade in which the tip end thereof is cooled effectively to decrease the metal temperature for the prevention of burning and the temperature gradient of blade metal is decreased to prevent the occurrence of cracking. In the gas turbine blade provided with a cooling passage therein, a protrusion is provided inwardly of the peripheral walls of the blade, which define the blade profile and the protrusion is positioned on the outer surface of blade tip end wall directly above a cooling passage within the blade.
    Type: Grant
    Filed: March 3, 1998
    Date of Patent: March 21, 2000
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventors: Kiyoshi Suenaga, Yasuoki Tomita, Hiroki Fukuno
  • Patent number: 6036436
    Abstract: There is provided a cooled stationary blade of a gas turbine in which the portions which can be cooled sufficiently by air are air-cooled, and the portions which are difficult to cool by air are steam-cooled, by which high temperatures can be overcome. In a stationary blade 1, there is formed a serpentine passage 3 in which cooling steam flows and an air passage 10 adjacent to the trailing edge portion and separated from the serpentine passage 3. Also, an outside shroud 4 is formed with an air cooling passage 16 at the outer edge portion and a steam impingement cooling portion 17 and an air impingement cooling portion 18 on the inside of the air cooling passage 16. An inside shroud 11 is provided with an air cooling passage 19 at the outer edge portion and shaped holes 20 formed on the inside of the air cooling passage 19. The air flowing out through the shaped holes 20 performs film cooling.
    Type: Grant
    Filed: October 2, 1998
    Date of Patent: March 14, 2000
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventors: Hiroki Fukuno, Yasuoki Tomita, Kiyoshi Suenaga