Patents by Inventor Kenjiro Narita

Kenjiro Narita 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: 9745866
    Abstract: A steam turbine stationary blade is configured to be a stationary blade structure having a hollow structure. The steam turbine stationary blade is provided with a slit disposed on a stationary blade surface. The pressure of a stationary blade hollow is reduced to suction a liquid film through the slit for removing the liquid film formed on the stationary blade surface. An opening portion of the slit is covered with a sheet in a meshed pattern formed of a fine mesh thereby reducing an accompanied steam amount so as to effectively remove the liquid film.
    Type: Grant
    Filed: July 31, 2014
    Date of Patent: August 29, 2017
    Assignee: Mitsubishi Hitachi Power Systems, Ltd.
    Inventors: Susumu Nakano, Koji Ishibashi, Kenjiro Narita, Takeshi Kudo
  • Publication number: 20150037144
    Abstract: A steam turbine stationary blade is configured to be a stationary blade structure having a hollow structure. The steam turbine stationary blade is provided with a slit disposed on a stationary blade surface. The pressure of a stationary blade hollow is reduced to suction a liquid film through the slit for removing the liquid film formed on the stationary blade surface. An opening portion of the slit is covered with a sheet in a meshed pattern formed of a fine mesh thereby reducing an accompanied steam amount so as to effectively remove the liquid film.
    Type: Application
    Filed: July 31, 2014
    Publication date: February 5, 2015
    Inventors: Susumu NAKANO, Koji ISHIBASHI, Kenjiro NARITA, Takeshi KUDO
  • Patent number: 8864443
    Abstract: A sealing structure in which free-cutting spacers on a sealing base plate and sealing fins on a rotor are opposed to each other is provided. The sealing base plate is disposed so as to be movable in an axial direction of the rotor. When a steam turbine increases in load, a pressure head moves in an axial steam-pressure loading direction of the rotor and the sealing base plate connected to the pressure head moves in the axial steam-pressure loading direction. Since the free-cutting spacers at positions opposed to those of the sealing fins existing after the movement of the sealing base plate are maintained in a non-contact state, clearances between the sealing fins and the free-cutting spacers are dimensionally minimized.
    Type: Grant
    Filed: July 13, 2011
    Date of Patent: October 21, 2014
    Assignee: Hitachi, Ltd.
    Inventors: Kenjiro Narita, Haruyuki Yamazaki, Takeshi Kudo, Kenichi Murata
  • Patent number: 8801373
    Abstract: A metal sealing material used in a sealing device which can reduce a gap between a stator and a rotor of a turbine. The metal sealing material used in a sealing device for a stator and a rotor of a turbine includes a surface layer and a lower layer composed of a porous metal layer, wherein the porosity of the surface layer is smaller than the porosity of the lower layer; the porosity of the surface layer is 60 to 65% and the porosity of the lower layer is 67 to 75% or less; and the porous metal layer has a thickness of 0.3 to 3.0 mm and may include, as a main component, an MCrAlY alloy where M is either one of Ni and Co or both thereof, and h-BN as a solid lubricant.
    Type: Grant
    Filed: June 29, 2010
    Date of Patent: August 12, 2014
    Assignee: Hitachi Ltd.
    Inventors: Yoshitaka Kojima, Hideyuki Arikawa, Akira Mebata, Hiroyuki Doi, Hajime Toriya, Kenjiro Narita
  • Publication number: 20140064939
    Abstract: A metal sealing material used in a sealing device which can reduce a gap between a stator and a rotor of a turbine. The metal sealing material used in a sealing device for a stator and a rotor of a turbine includes a surface layer and a lower layer composed of a porous metal layer, wherein the porosity of the surface layer is smaller than the porosity of the lower layer; the porosity of the surface layer is 60 to 65% and the porosity of the lower layer is 67 to 75% or less; and the porous metal layer has a thickness of 0.3 to 3.0 mm and may include, as a main component, an MCrAlY alloy where M is either one of Ni and Co or both thereof, and h-BN as a solid lubricant.
    Type: Application
    Filed: August 28, 2013
    Publication date: March 6, 2014
    Applicant: HITACHI, LTD.
    Inventors: Yoshitaka KOJIMA, Hideyuki ARIKAWA, Akira MEBATA, Hiroyuki DOI, Hajime TORIYA, Kenjiro NARITA
  • Patent number: 8500397
    Abstract: A seal structure for a steam turbine is provided, which is capable of suppressing transfer of heat generated by a friction between a rotating portion and a fixed portion to the rotating portion and of suppressing an increase in the temperature of the rotating portion. A labyrinth seal device serves to suppress the amount of steam leaking from a clearance present between each stator blade (fixed portion) of the steam turbine and a rotor (rotating portion). The seal structure for the steam turbine is formed to ensure that permeable spacers made of a permeable metal are provided on the rotor and a seal stationary body and face respective seal fins provided in the labyrinth seal device.
    Type: Grant
    Filed: February 14, 2012
    Date of Patent: August 6, 2013
    Assignee: Hitachi, Ltd.
    Inventors: Kenjiro Narita, Haruyuki Yamazaki, Hiroyuki Doi, Kei Kobayashi, Hajime Toriya
  • Publication number: 20120148389
    Abstract: A seal structure for a steam turbine is provided, which is capable of suppressing transfer of heat generated by a friction between a rotating portion and a fixed portion to the rotating portion and of suppressing an increase in the temperature of the rotating portion. A labyrinth seal device serves to suppress the amount of steam leaking from a clearance present between each stator blade (fixed portion) of the steam turbine and a rotor (rotating portion). The seal structure for the steam turbine is formed to ensure that permeable spacers made of a permeable metal are provided on the rotor and a seal stationary body and face respective seal fins provided in the labyrinth seal device.
    Type: Application
    Filed: February 14, 2012
    Publication date: June 14, 2012
    Applicant: HITACHI, LTD.
    Inventors: Kenjiro NARITA, Haruyuki YAMAZAKI, Hiroyuki DOI, Kei KOBAYASHI, Hajime TORIYA
  • Patent number: 8128351
    Abstract: A seal structure for a steam turbine is provided, which is capable of suppressing transfer of heat generated by a friction between a rotating portion and a fixed portion to the rotating portion and of suppressing an increase in the temperature of the rotating portion. A labyrinth seal device serves to suppress the amount of steam leaking from a clearance present between each stator blade (fixed portion) of the steam turbine and a rotor (rotating portion). The seal structure for the steam turbine is formed to ensure that permeable spacers made of a permeable metal are provided on the rotor and a seal stationary body and face respective seal fins provided in the labyrinth seal device.
    Type: Grant
    Filed: December 2, 2008
    Date of Patent: March 6, 2012
    Assignee: Hitachi, Ltd.
    Inventors: Kenjiro Narita, Haruyuki Yamazaki, Hiroyuki Doi, Kei Kobayashi, Hajime Toriya
  • Publication number: 20120014778
    Abstract: Subject: To provide a sealing structure, and control method therefor, which improve sealing performance between a rotating region and a fixed region, prevent fins from being damaged, and prevent increases in the amount of steam leakage from any clearances newly formed by further abrasion of an abradable material. Solution: The sealing structure in which free-cutting spacers 28 on a sealing base plate 25 and sealing fins 24 on a rotor 18 are opposed to each other is provided, in the sealing structure of which the sealing base plate 25 is disposed so as to be movable in an axial direction of the rotor 18. When a steam turbine 3 increases in load, a pressure head 30 moves in an axial steam-pressure loading direction of the rotor 18 and the sealing base plate 25 connected to the pressure head 30 moves in the axial steam-pressure loading direction.
    Type: Application
    Filed: July 13, 2011
    Publication date: January 19, 2012
    Applicant: Hitachi, Ltd.
    Inventors: Kenjiro NARITA, Haruyuki YAMAZAKI, Takeshi KUDO, Kenichi MURATA
  • Patent number: 7985045
    Abstract: A steam turbine comprises a rotor with moving blades attached thereto; diaphragms which surround the rotor from an outer periphery side of the rotor; a casing which encloses the diaphragms and the rotor and has an upper half and a lower half clamped together through respective flanges; a displacement detector for measuring a difference d in thermal expansion in the rotor axis direction between the casing and the rotor; heating/cooling devices attached to the flanges respectively to heat and cool the flanges; and a controller which makes control so that the flanges are heated or cooled by the heating/cooling devices until a measured value obtained by the displacement detector reaches a preset value M or S in unsteady operation.
    Type: Grant
    Filed: July 18, 2007
    Date of Patent: July 26, 2011
    Assignee: Hitachi, Ltd.
    Inventors: Kenjiro Narita, Takeshi Kudo
  • Publication number: 20110014035
    Abstract: A metal sealing material used in a sealing device which can reduce a gap between a stator and a rotor of a turbine. The metal sealing material used in a sealing device for a stator and a rotor of a turbine includes a surface layer and a lower layer composed of a porous metal layer, wherein the porosity of the surface layer is smaller than the porosity of the lower layer; the porosity of the surface layer is 60 to 65% and the porosity of the lower layer is 67 to 75% or less; and the porous metal layer has a thickness of 0.3 to 3.0 mm and may include, as a main component, an MCrAlY alloy where M is either one of Ni and Co or both thereof, and h-BN as a solid lubricant.
    Type: Application
    Filed: June 29, 2010
    Publication date: January 20, 2011
    Inventors: Yoshitaka KOJIMA, Hideyuki Arikawa, Akira Mebata, Hiroyuki Doi, Hajime Toriya, Kenjiro Narita
  • Publication number: 20100278645
    Abstract: Provided are a seal structure and a control method therefor that can improve sealing performance between a rotating portion and a fixed portion, smoothly start up a steam turbine, and suppress the temperature rise of the rotating portion even if the rotating portion is continuously rotated for a long period of time. A seal structure is configured such that seal fins 62 on a seal base-plate 61 side and corresponding breathable spacers 4b on a rotor 2a side are opposed to each other and breathable spacers 4a on the seal base-plate 61 side and corresponding seal fins 2a1 on the rotor 2a side are opposed to each other. The seal base-plate 61 is installed shiftably in a direction coming close to or moving away from the rotor 2a. If steam St has low pressure, the seal fins 62 and the corresponding breathable spacers 4b are not in contact with each other and the seal fins 2a1 and the corresponding breathable spacers 4a are not in contact with each other.
    Type: Application
    Filed: April 28, 2010
    Publication date: November 4, 2010
    Applicant: Hitachi, Ltd.
    Inventors: Kenjiro NARITA, Haruyuki Yamazaki, Hiroyuki Doi, Kei Kobayashi, Hajime Toriya, Takeshi Kudo, Yoshitaka Kojima
  • Publication number: 20090142187
    Abstract: A seal structure for a steam turbine is provided, which is capable of suppressing transfer of heat generated by a friction between a rotating portion and a fixed portion to the rotating portion and of suppressing an increase in the temperature of the rotating portion. A labyrinth seal device serves to suppress the amount of steam leaking from a clearance present between each stator blade (fixed portion) of the steam turbine and a rotor (rotating portion). The seal structure for the steam turbine is formed to ensure that permeable spacers made of a permeable metal are provided on the rotor and a seal stationary body and face respective seal fins provided in the labyrinth seal device.
    Type: Application
    Filed: December 2, 2008
    Publication date: June 4, 2009
    Inventors: Kenjiro NARITA, Haruyuki Yamazaki, Hiroyuki Doi, Kei Kobayashi, Hajime Toriya
  • Publication number: 20080019821
    Abstract: A steam turbine comprises a rotor with moving blades attached thereto; diaphragms which surround the rotor from an outer periphery side of the rotor; a casing which encloses the diaphragms and the rotor and has an upper half and a lower half clamped together through respective flanges; a displacement detector for measuring a difference d in thermal expansion in the rotor axis direction between the casing and the rotor; heating/cooling devices attached to the flanges respectively to heat and cool the flanges; and a controller which makes control so that the flanges are heated or cooled by the heating/cooling devices until a measured value obtained by the displacement detector reaches a preset value M or S in unsteady operation.
    Type: Application
    Filed: July 18, 2007
    Publication date: January 24, 2008
    Inventors: Kenjiro Narita, Takeshi Kudo
  • Patent number: 6955287
    Abstract: An upper shearing blade equipped with a protrusion of a triangle-columnar shape and a lower shearing blade equipped with a protrusion of the same shape are applied onto the overlapped portion of metal plates to be bonded, and then pressed into the metal plates in an oblique direction inclined with respect to the thickness direction by a stroke in such a range that the metal plates are not completely cut off. The operating loci of the upper, shearing blade and the lower shearing blade are overlapped each other so that one falls inside the other, and the sheared surfaces of the metal plates are formed into a bonded portion by plastic flow deformation. Therein, since a compressive force is applied onto the portions to be bonded, the portion being defined by the amount of overlap, and the portions are compressed to form a compressed portion after completion of bonding, the bonding strength enhances.
    Type: Grant
    Filed: December 14, 2000
    Date of Patent: October 18, 2005
    Assignees: Hitachi, Ltd., Pohang Iron and Steel Co., Ltd., Research Institution of Industrial Science and Technology
    Inventors: Kenji Horii, Yasutsugu Yoshimura, Tadashi Nishino, Takashi Kamoshita, Takayoshi Tomino, Fuminori Ishikawa, Takao Funamoto, Takashi Mashiko, Kenjiro Narita, Jong-Keun Kim, Ki-Chol Kim, Jong-Sub Lee, Hwang-Kyu Hwang, Jung-Sik Lee, Jin-Hee Kim
  • Patent number: 6708547
    Abstract: There are disclosed a rolling mill capable of keeping a uniform plate of thickness distribution and manufacturing a good-quality plate, and a rolling method. The rolling mill comprises working rolls movable in roll axis directions, profile-measuring means for measuring the profile of each of the working rolls, profile-estimating means for estimating the profile thereof, and a grinder for grinding each of the working rolls. The rolling mill also comprises instructing means for sending a command of grinding to the grinder at a time when the measured profile value or the estimated profile value regarding each of the working rolls reaches a given value.
    Type: Grant
    Filed: March 26, 2002
    Date of Patent: March 23, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Kenjiro Narita, Mitsuo Nihei, Takehiko Saito, Toshiyasu Shinmura, Shinichi Kaga, Takashi Kamoshita
  • Publication number: 20020100307
    Abstract: There are disclosed a rolling mill capable of keeping a uniform plate of thickness distribution and manufacturing a good-quality plate, and a rolling method. The rolling mill comprises working rolls movable in roll axis directions, profile-measuring means for measuring the profile of each of the working rolls, profile-estimating means for estimating the profile there of, and a grinder for grinding each of the working rolls. The rolling mill also comprises instructing means for sending a command of grinding to the grinder at a time when the measured profile value or the estimated profile value regarding each of the working rolls reaches a given value.
    Type: Application
    Filed: March 26, 2002
    Publication date: August 1, 2002
    Applicant: HITACHI, LTD.
    Inventors: Kenjiro Narita, Mitsuo Nihei, Takehiko Saito, Toshiyasu Shinmura, Shinichi Kaga, Takashi Kamoshita
  • Patent number: 6408666
    Abstract: There are disclosed a rolling mill capable of keeping a uniform plate thickness distribution and manufacturing a good-quality plate, and a rolling method. The rolling mill comprises working rolls movable in roll axis directions, profile-measuring means for measuring the profile of each of the working rolls, profile-estimating means for estimating the profile thereof, and a grinder for grinding each of the working rolls. The rolling mill also comprises instructing means for sending a command of grinding to the grinder at a time when the measured profile value or the estimated profile value regarding each of the working rolls reaches a given value.
    Type: Grant
    Filed: September 11, 2000
    Date of Patent: June 25, 2002
    Assignee: Hitachi, Ltd.
    Inventors: Kenjiro Narita, Mitsuo Nihei, Takehiko Saito, Toshiyasu Shinmura, Shinichi Kaga, Takashi Kamoshita
  • Publication number: 20010017312
    Abstract: An upper shearing blade 3 equipped with a protrusion 30 of a triangle-columnar shape and a lower shearing blade 4 equipped with a protrusion 40 of the same shape are applied onto the overlapped portion of metal plates 1 and 2 to be bonded, and then pressed into the metal plates 1 and 2 in an oblique direction inclined with respect to the thickness direction by a stroke in such a range that the metal plates 1 and 2 are not completely cut off. The operating loci of the upper shearing blade 3 and the lower shearing blade 4 are overlapped each other so that one falls inside the other, and the sheared surfaces of the metal plates 1 and 2 are formed into a bonded portion by plastic flow deformation. Therein, since a compressive force is applied onto the portions to be bonded, the portion being defined by the amount of overlap, and the portions are compressed to form a compressed portion after completion of bonding, the bonding strength enhances.
    Type: Application
    Filed: December 14, 2000
    Publication date: August 30, 2001
    Applicant: HITACHI, LTD., POHANG IRON & STEEL CO., LTD.
    Inventors: kenji Horii, Yasutsugu Yoshimura, Tadashi Nishino, Takashi Kamoshita, Takayoshi Tomino, Fuminori Ishikawa, Takao Funamoto, Takashi Mashiko, Kenjiro Narita, Jong-Keun Kim, Ki-Chol Kim, Jong-Sub Lee, Hwang-Kyu Hwang, Jung-Sik Lee, Jin-Hee kim
  • Patent number: 6012319
    Abstract: A rolling mill is provided with a pair of work rolls 2, a pair of intermediate rolls 3 and a pair of backup rolls 4 in a mill stand 5, wherein the pair of backup rolls are arranged so that their axial lines cross perpendicularly a plate travelling direction and do not incline to the direction in a horizontal plane, the intermediate rolls and work rolls are arranged so that the axial lines of the intermediate rolls and the axial line of the work rolls incline to (cross) the axes of the backup rolls in a counter direction to each other in a horizontal plane, and a lubricant supplying apparatus 6 is provided for supplying a lubricant to the roll surfaces.
    Type: Grant
    Filed: December 29, 1997
    Date of Patent: January 11, 2000
    Assignee: Hitachi, Ltd.
    Inventors: Kenjiro Narita, Mitsuo Nihei, Kenichi Yasuda, Takehiko Saito, Yukio Hirama, Kouji Satou