Patents by Inventor Yohei Magara

Yohei Magara 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: 11137026
    Abstract: The present invention is to reduce the load on a control device by reliably classifying vibration modes of a rotor, thereby facilitating stabilization design of a magnetic bearing. The present invention includes: magnetic bearings including electromagnets provided at one end and the other end of a rotor to contactlessly support the one end and the other end of the rotor by the magnetic attraction forces of the electromagnets; and displacement sensors that measure an inclination at the one end of the rotor and an inclination at the other end of the rotor, in which the magnetic attraction forces of the electromagnets are controlled based on the inclinations measured by the displacement sensors.
    Type: Grant
    Filed: February 20, 2018
    Date of Patent: October 5, 2021
    Assignee: Hitachi, Ltd.
    Inventors: Toyomi Yoshida, Kazuyuki Yamaguchi, Yohei Magara, Kiyoshi Yabata
  • Publication number: 20200080591
    Abstract: The present invention is to reduce the load on a control device by reliably classifying vibration modes of a rotor, thereby facilitating stabilization design of a magnetic bearing. The present invention includes: magnetic bearings including electromagnets provided at one end and the other end of a rotor to contactlessly support the one end and the other end of the rotor by the magnetic attraction forces of the electromagnets; and displacement sensors that measure an inclination at the one end of the rotor and an inclination at the other end of the rotor, in which the magnetic attraction forces of the electromagnets are controlled based on the inclinations measured by the displacement sensors.
    Type: Application
    Filed: February 20, 2018
    Publication date: March 12, 2020
    Inventors: Toyomi YOSHIDA, Kazuyuki YAMAGUCHI, Yohei MAGARA, Kiyoshi YABATA
  • Publication number: 20160273324
    Abstract: A downhole compressor includes: a casing disposed inside a gas well; a rotor built inside the casing; and an impeller disposed at the rotor, and an electromagnetic control unit that electromagnetically controls a relative position of the rotor inside the casing is provided.
    Type: Application
    Filed: February 25, 2016
    Publication date: September 22, 2016
    Inventors: Kazuyuki YAMAGUCHI, Yohei MAGARA, Toyomi YOSHIDA
  • Patent number: 9004857
    Abstract: In a centrifugal compressor, for the purpose of preventing the positions of a diaphragm and a head flange in a radial direction from moving with respect to a casing, preventing the unstable vibration of the rotor and enabling an efficient and stable operation even on high-pressure conditions, there is provided a barrel-shaped centrifugal compressor including a casing, a diaphragm located in the casing to define a flow channel, and a head flange attached to the end of the casing by a shear key, wherein in the inner peripheral surface of the casing and the outer peripheral surface of abutment portions of the diaphragm and the head flange in which they are abutted on the inner peripheral surface of the casing, sliding key grooves which are vertical to the surfaces are provided at least two portions in a peripheral direction, and sliding keys are provided in the key grooves.
    Type: Grant
    Filed: June 22, 2011
    Date of Patent: April 14, 2015
    Assignee: Hitachi, Ltd.
    Inventors: Yohei Magara, Kazuyuki Yamaguchi, Mitsuhiro Narita, Haruo Miura, Naohiko Takahashi, Akira Endo
  • Patent number: 8388311
    Abstract: A turbomachinery includes a labyrinth seal (2) to prevent unstable vibration of a rotor formed by dividing the seal into segments (7) in a circumferential direction and combining the segments (7) whose comb teeth (5) differ in height. The labyrinth seal (2) preferably includes two kinds of segments (7) whose comb teeth (5) differ in height for each kind of segment, and the segments (7a) of the greater comb tooth height are arranged in a certain reference direction on a cross section right-angled to a rotational axis, and in a direction opposite to the reference direction, and the segments (7b) of the smaller comb tooth height are arranged in a direction right-angled to the reference direction, and in a direction opposite to that right-angled to the reference direction.
    Type: Grant
    Filed: June 25, 2009
    Date of Patent: March 5, 2013
    Assignee: Hitachi, Ltd.
    Inventors: Kazuyuki Yamaguchi, Yohei Magara, Toyomi Yoshida, Michiyuki Takagi, Kenichi Murata, Takeshi Kudo
  • Publication number: 20120121411
    Abstract: A labyrinth seal is provided that can suppress the occurrence of an unequal pressure pattern in the seal, suppress unstable vibration of a rotating shaft and ensure sealing performance. The labyrinth seal includes a seal ring 13 and a plurality of seal fins 11. Ring-like cavities 12 are defined on the outer circumference of the rotating shaft 2 with the seal ring 13 and the seal fins 11. The ring-like cavities 12 suppress a leakage flow LS moving along the outer circumference of the rotating shaft 2. Void portions 14 are each provided on the outer circumferential side of the cavity 12 in the seal ring 13 so as to extend in the circumferential direction of the rotating shaft 2 and communicate with the cavity 12 at circumferential intervals to temporarily relieve a leakage flow from inside the cavity in the circumferential direction.
    Type: Application
    Filed: November 9, 2011
    Publication date: May 17, 2012
    Applicant: Hitachi, Ltd.
    Inventors: Akira ENDO, Kazuyuki YAMAGUCHI, Yohei MAGARA, Toyomi YOSHIDA, Michiyuki TAKAGI, Kenichi MURATA, Takeshi KUDO
  • Publication number: 20110318163
    Abstract: In a centrifugal compressor, for the purpose of preventing the positions of a diaphragm and a head flange in a radial direction from moving with respect to a casing, suppressing the generation of an unstable fluid force in a seal and the contact of the seal with a rotor to prevent the unstable vibration of the rotor and enabling an efficient and stable operation even on high-pressure conditions, there is provided a barrel-shaped centrifugal compressor including a casing, a diaphragm located in the casing to define a flow channel, and a head flange attached to the end of the casing by a shear key, wherein in the inner peripheral surface of the casing and the outer peripheral surface of abutment portions of the diaphragm and the head flange in which they are abutted on the inner peripheral surface of the casing, sliding key grooves which are vertical to the surfaces are provided at least two portions in a peripheral direction, and sliding keys are provided in the key grooves.
    Type: Application
    Filed: June 22, 2011
    Publication date: December 29, 2011
    Inventors: Yohei Magara, Kazuyuki Yamaguchi, Mitsuhiro Narita, Haruo Miura, Naohiko Takahashi, Akira Endo
  • Publication number: 20100166544
    Abstract: Disclosed herein is a turbomachinery including a labyrinth seal easy to fabricate and adapted to prevent unstable vibration of a rotor. A turbomachinery according to this invention includes a labyrinth seal 2 formed by dividing the seal into segments 7 in a circumferential direction and combining the segments 7 whose comb teeth 5 differ in height. The labyrinth seal 2 preferably includes two kinds of segments 7 whose comb teeth 5 differ in height for each kind of segment, and the segments 7a of the greater comb tooth height are arranged in a certain reference direction on a cross section right-angled to a rotational axis, and in a direction opposite to the reference direction, and the segments 7b of the smaller comb tool height are arranged in a direction right-angled to the reference direction, and in a direction opposite to that right-angled to the reference direction.
    Type: Application
    Filed: June 25, 2009
    Publication date: July 1, 2010
    Applicant: HITACHI, LTD.
    Inventors: Kazuyuki Yamaguchi, Yohei Magara, Toyomi Yoshida, Michiyuki Takagi, Kenichi Murata, Takeshi Kudo
  • Publication number: 20100034646
    Abstract: The present invention provides a centrifugal compressor that inhibits possible leakage while reducing a destabilizing fluid force generated in a seal to prevent the possible instable vibration of a rotor. The centrifugal compressor includes a casing, a rotor rotatably installed in the casing and having an impeller, and seals provided in the clearance between the casing and the rotor to prevent a fluid from leaking through the clearance from a high pressure side to a low pressure side. The rotor rotates to compress gas. For example, the balance piston seal is composed of a damper seal with a plurality of holes and a labyrinth seal with an annular parallel groove; the damper seal and the labyrinth seal are continuously provided. The damper seal is disposed on the high pressure side in a leakage flow direction. The labyrinth seal is disposed on the low pressure side in the leakage flow direction.
    Type: Application
    Filed: August 3, 2009
    Publication date: February 11, 2010
    Applicant: HITACHI PLANT TECHNOLOGIES, LTD.
    Inventors: Yohei MAGARA, Kazuyuki YAMAGUCHI, Tetsuya KUWANO, Haruo MIURA, Naohiko TAKAHASHI