Patents by Inventor Koichi Akagi

Koichi Akagi 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: 6089827
    Abstract: A gas turbine rotor, in which a plurality of discs having teeth of a bevel gear are juxtaposed to engage the teeth and are integrally fastened by a bolt extending through the discs, so that the discs may be cooled by feeding cooling air to the air passages of the individual discs sequentially at the running time, is provided whereby the cooling air is prevented from leaking by means having no wear.
    Type: Grant
    Filed: February 9, 1999
    Date of Patent: July 18, 2000
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventors: Taku Ichiryu, Koichi Akagi, Yasuoki Tomita
  • Patent number: 6050776
    Abstract: A gas turbine stationary blade unit in which two stationary blades are formed in a single segment by divided shrouds functions to lessen the occurrence of cracks. Two stationary blades 1a, 1b are fixed to an outer shroud and an inner shroud, respectively. Each shroud is divided into two sections 2a, 2b and 3a, 3b. Flanges 4a, 4b are provided to connect the section together by bolts via boltholes 7. Likewise, flanges 5a, 5b are provided to form a similar connection or joint. If the two stationary blades 1a, 1b are fixed in a single segment by the shrouds which are not divided, a restraining force becomes larger, local stress occurs due to thermal stress and the frequency of crack occurrence increases. However, since the shrouds are divided respectively into two parts and jointed together by bolts, the crack occurrence is lessened. Also, pinholes are provided in opposing faces at the divided portion of the shrouds.
    Type: Grant
    Filed: September 14, 1998
    Date of Patent: April 18, 2000
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventors: Koichi Akagi, Yukihiro Hashimoto, Masahito Kataoka, Yasuoki Tomita, Hiroji Tada
  • Patent number: 5967746
    Abstract: In order to realize a seal device of a gas turbine interstage portion which is excellent in a sealing ability during regular operation of the gas turbine, a gas turbine interstage portion seal device is constructed comprising a honeycomb seal (2) of a ring shape provided to an inner side of a turbine stationary blade inner ring (1) and a plurality of seal fins (5) of a ring shape provided to an outer side of a turbine disc seal arm portion (4). Also, an inner side surface of the honeycomb seal and outer peripheries of the plurality of seal fins, comprise large diameters and small diameters, and convex and concave portions formed thereby respectively are mated with each other.
    Type: Grant
    Filed: July 29, 1998
    Date of Patent: October 19, 1999
    Assignee: Mitsubishi Heavy Industries, Ltd.
    Inventors: Naoki Hagi, Koichi Akagi
  • Patent number: 5755622
    Abstract: A vibration reducer for a diaphragm coupling is capable of suppressing axial vibrations as well as torsional vibrations. A diaphragm pack 3 is mounted between a diaphragm mount flange 2 provided on an intermediate shaft 1 serving as a drive shaft and a shaft flange 4 of another shaft serving as a driven shaft. An elastic arm 5 extends through the diaphragm pack 3 and is mounted to the diaphragm mount flange 2. The elastic arm 5 is a cylindrical member, whose circumferential portion is severed by slits formed by wire-cutting. Free ends 5a of the elastic arm 5 are expanded in the radial directions by centrifugal forces caused by rotation of a shafts and come into pressure-contact with the liner member 8 formed integrally within a cylindrical portion 7 of the shaft flange 4. A part of a torque is thereby transmitted via the pressure-contact portion, and rigidity in the axial direction of the elastic arm 5 is added to that of the diaphragm pack 3 to suppress vibrations.
    Type: Grant
    Filed: April 21, 1994
    Date of Patent: May 26, 1998
    Assignee: Mitsubish Jukogyo Kabushiki Kaisha
    Inventors: Hiroshi Kanki, Tadao Yashiki, Koichi Akagi, Taku Ichiryu