Patents by Inventor Takuma Sasai

Takuma Sasai 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).

  • Publication number: 20240097510
    Abstract: Provided are a magnetic gear device and a rotating electrical machine having intermediate cylindrical portions with increased rigidity against radial-direction external forces. In a magnetic gear device and a rotating electrical machine according to the present disclosure, an intermediate cylindrical portion includes: magnetic-pole portions arranged in a circumferential direction; frame-shaped spacers penetrating in the radial direction, arranged in the circumferential direction alternately with the magnetic-pole portions, and each having two side-wall portions contacting with the adjacent magnetic-pole portions; end plates provided at both ends of the magnetic-pole portions and the spacers in an axial direction of a rotary shaft; and reinforcement portions placed inside the spacers while being pressed to inner surfaces of the side-wall portions in the circumferential direction, to apply forces in the circumferential direction to the adjacent magnetic-pole portions via the spacer.
    Type: Application
    Filed: March 18, 2021
    Publication date: March 21, 2024
    Applicant: Mitsubishi Electric Corporation
    Inventors: Kohei SAMATA, Takuma SASAI, Norihiko HANA
  • Publication number: 20230145798
    Abstract: A coupling bellows includes a first bellows and a second bellows having a higher spring constant than the first bellows. A coupling member is joined to each of the first bellows and the second bellows adjacent to each other, and includes a hole inserted with a movable shaft. A pressing member moves in an axial direction of the movable shaft toward the coupling member along with movement of the movable shaft in the direction in which a movable contactor is separated from a fixed contactor, and presses the coupling member, thereby contracting the second bellows.
    Type: Application
    Filed: May 20, 2020
    Publication date: May 11, 2023
    Applicant: Mitsubishi Electric Corporation
    Inventors: Yusuke TOMIZAWA, Takuma SASAI, Masao AKIYOSHI
  • Patent number: 11527987
    Abstract: Provided is an abnormality diagnosis device including: a physical quantity measurement processor configured to acquire, as time-series data, a physical quantity of an electric motor or a load; a feature parameter calculation processor configured to calculate feature parameters; a correlation function creation processor configured to create a correlation function for two or more feature parameters, and calculate a correlation coefficient corresponding to a measurement result of the physical quantity that changes depending on an abnormality occurrence state; a database configured to store in advance reference data in which a remaining time until a failure is caused and the correlation coefficient are associated with each other; and a diagnosis processor configured to extract from the reference data the remaining time corresponding to the correlation coefficient, and identify the remaining time until the electric motor or the load causes a failure or a part that has caused a failure.
    Type: Grant
    Filed: December 27, 2018
    Date of Patent: December 13, 2022
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Hiroshi Inoue, Makoto Kanemaru, Junji Hori, Tomoaki Takewa, Takuma Sasai
  • Patent number: 11489424
    Abstract: A squirrel-cage induction rotating electrical machine comprises: a solid rotor, a stator, and bearings. The solid rotor includes a shaft part, a columnar-shaped rotor core part integrally formed with the shaft part and having rotor slots formed therein, and a plurality of conductor bars passing through the respective rotor slots and coupled together at both axial ends outside the rotor core part. The stator includes a cylindrical stator core provided radially outside the rotor core part, and stator windings passing through a plurality of respective stator slots which are formed in the radially inner surface of the stator core. An outer wall and an inner wall of each rotor slot are tilted at a predetermined angle or more with respect to a plane including a rotation axis of the shaft part.
    Type: Grant
    Filed: June 11, 2020
    Date of Patent: November 1, 2022
    Assignee: TOSHIBA MITSUBISHI-ELECTRIC INDUSTRIAL SYSTEMS CORPORATION
    Inventors: Yuichi Tsuboi, Satoshi Kurita, Haruyuki Kometani, Takuma Sasai
  • Publication number: 20220006417
    Abstract: Provided is an abnormality diagnosis device including: a physical quantity measurement processor configured to acquire, as time-series data, a physical quantity of an electric motor or a load; a feature parameter calculation processor configured to calculate feature parameters; a correlation function creation processor configured to create a correlation function for two or more feature parameters, and calculate a correlation coefficient corresponding to a measurement result of the physical quantity that changes depending on an abnormality occurrence state; a database configured to store in advance reference data in which a remaining time until a failure is caused and the correlation coefficient are associated with each other; and a diagnosis processor configured to extract from the reference data the remaining time corresponding to the correlation coefficient, and identify the remaining time until the electric motor or the load causes a failure or a part that has caused a failure.
    Type: Application
    Filed: December 27, 2018
    Publication date: January 6, 2022
    Applicant: Mitsubishi Electric Corporation
    Inventors: Hiroshi INOUE, Makoto KANEMARU, Junji HORI, Tomoaki TAKEWA, Takuma SASAI
  • Patent number: 11018549
    Abstract: A dynamic vibration absorber needs to be designed so that the natural frequency of the dynamic vibration absorber alone becomes equal to the natural frequency of a stator. If these natural frequencies greatly deviate from each other, the effect is reduced. Therefore, the natural frequency of the dynamic vibration absorber alone needs to be accurately calculated to make designing. However, in actual, the natural frequency is greatly influenced by the rigidity around the mounting position of a vibration damping target, and thus there is a problem that the natural frequency becomes different from the designed value upon mounting. An object of the present invention is to reduce an influence on the natural frequency of the dynamic vibration absorber alone given by the rigidity around the mounting position, by mounting a plurality of dynamic vibration absorbers to a dynamic vibration absorber mounting member, thereby making the dynamic vibration absorber more effective.
    Type: Grant
    Filed: January 5, 2016
    Date of Patent: May 25, 2021
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Koji Kawashima, Fumio Matsumoto, Takaaki Nagashima, Takuma Sasai
  • Publication number: 20200304001
    Abstract: A squirrel-cage induction rotating electrical machine comprises: a solid rotor, a stator, and bearings. The solid rotor includes a shaft part, a columnar-shaped rotor core part integrally formed with the shaft part and having rotor slots formed therein, and a plurality of conductor bars passing through the respective rotor slots and coupled together at both axial ends outside the rotor core part. The stator includes a cylindrical stator core provided radially outside the rotor core part, and stator windings passing through a plurality of respective stator slots which are formed in the radially inner surface of the stator core. An outer wall and an inner wall of each rotor slot are tilted at a predetermined angle or more with respect to a plane including a rotation axis of the shaft part.
    Type: Application
    Filed: June 11, 2020
    Publication date: September 24, 2020
    Applicant: Toshiba Mitsubishi-Electric Industrial Systems Corporation
    Inventors: Yuichi TSUBOI, Satoshi KURITA, Haruyuki KOMETANI, Takuma SASAI
  • Publication number: 20180367002
    Abstract: A dynamic vibration absorber needs to be designed so that the natural frequency of the dynamic vibration absorber alone becomes equal to the natural frequency of a stator. If these natural frequencies greatly deviate from each other, the effect is reduced. Therefore, the natural frequency of the dynamic vibration absorber alone needs to be accurately calculated to make designing. However, in actual, the natural frequency is greatly influenced by the rigidity around the mounting position of a vibration damping target, and thus there is a problem that the natural frequency becomes different from the designed value upon mounting. An object of the present invention is to reduce an influence on the natural frequency of the dynamic vibration absorber alone given by the rigidity around the mounting position, by mounting a plurality of dynamic vibration absorbers to a dynamic vibration absorber mounting member, thereby making the dynamic vibration absorber more effective.
    Type: Application
    Filed: January 5, 2016
    Publication date: December 20, 2018
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Koji KAWASHIMA, Fumio MATSUMOTO, Takaaki NAGASHIMA, Takuma SASAI
  • Patent number: 9935513
    Abstract: According to an electric motor, a cooling hole is formed outside of a circular arc-like region having an intersection between extension lines from inner side surfaces of adjacent permanent magnets as a center of the circular arc-like region and a distance between the intersection and an intermediate point on the side surface of the permanent magnet as a radius of the circular arc-like region. Thus, heat generation by a magnetic resistance due to the cooling hole is suppressed to improve efficiency.
    Type: Grant
    Filed: April 22, 2013
    Date of Patent: April 3, 2018
    Assignee: Mitsubishi Electric Corporation
    Inventors: Hirohisa Yokota, Takuma Sasai, Moriyuki Hazeyama, Shinsuke Kayano
  • Patent number: 9735631
    Abstract: Permanent magnets that constitute the single magnetic poles are constituted by n permanent magnet segments, the n permanent magnet segments being configured such that shapes and directions of orientation thereof have mirror symmetry relative to a plane that passes through a magnetic pole center and that includes a central axis of the rotor core, and being oriented such that a permanent magnet segment that is further away from the magnetic pole center in a circumferential direction has a smaller angle of orientation, and the permanent magnet segment that is positioned further away from the magnetic pole center in the circumferential direction being produced so as to have an approximately fan-shaped cross-sectional shape in which a radial width is wider than a circumferential width.
    Type: Grant
    Filed: May 22, 2012
    Date of Patent: August 15, 2017
    Assignee: Mitsubishi Electric Corporation
    Inventors: Shinsuke Kayano, Masaya Inoue, Shinji Nishimura, Moriyuki Hazeyama, Takuma Sasai
  • Patent number: 9595851
    Abstract: Permanent magnets that form individual magnetic poles are configured by arranging three magnet blocks to be spaced apart from each other circumferentially, the three magnet blocks are each formed such that cross-sectional shapes that are perpendicular to a central axis of a rotor core are radially outwardly convex, and circumferential widths are narrower in magnet blocks that are further away from a magnetic pole center, and the three magnet blocks that are arranged circumferentially are formed to have mirror symmetry relative to a plane that passes through the magnetic pole center and the central axis of the rotor core.
    Type: Grant
    Filed: January 17, 2014
    Date of Patent: March 14, 2017
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Moriyuki Hazeyama, Takuma Sasai, Shinsuke Kayano, Masaya Inoue, Shinji Nishimura, Akihiro Daikoku
  • Publication number: 20160079820
    Abstract: A rotating electrical machine includes: a stator that includes a cylindrical inner hole; and a rotor that includes a rotation shaft being concentric with the inner hole of the stator and whose outer peripheral surface faces an inner peripheral surface of the inner hole across a predetermined gap, wherein a rotor core that is provided around the rotation shaft is divided into a plurality of portions in an axis direction thereof, and, inside each of rotor cores that are created by the division, a plurality of ventilation holes are formed around the rotation shaft in such a way as to pass therethrough in an axis direction thereof, and a spacer is provided between end surfaces of the rotor cores, and a duct is formed in such a way as to extend from the ventilation holes to the gap with the inner peripheral surface of the inner hole of the stator.
    Type: Application
    Filed: January 22, 2014
    Publication date: March 17, 2016
    Applicant: TOSHIBA MITSUBISHI-ELECTRIC INDUSTRIAL SYSTEMS CORPORATION
    Inventors: Hirotake NAKAJI, Yuichi TSUBOI, Haruyuki KOMETANI, Takuma SASAI, Koji KISE
  • Publication number: 20160006307
    Abstract: According to an electric motor, a cooling hole is formed outside of a circular arc-like region having an intersection between extension lines from inner side surfaces of adjacent permanent magnets as a center of the circular arc-like region and a distance between the intersection and an intermediate point on the side surface of the permanent magnet as a radius of the circular arc-like region. Thus, heat generation by a magnetic resistance due to the cooling hole is suppressed to improve efficiency.
    Type: Application
    Filed: April 22, 2013
    Publication date: January 7, 2016
    Applicant: Mitsubishi Electric Corporation
    Inventors: Hirohisa YOKOTA, Takuma SASAI, Moriyuki HAZEYAMA, Shinsuke KAYANO
  • Publication number: 20150357870
    Abstract: Permanent magnets that form individual magnetic poles are configured by arranging three magnet blocks to be spaced apart from each other circumferentially, the three magnet blocks are each formed such that cross-sectional shapes that are perpendicular to a central axis of a rotor core are radially outwardly convex, and circumferential widths are narrower in magnet blocks that are further away from a magnetic pole center, and the three magnet blocks that are arranged circumferentially are formed to have mirror symmetry relative to a plane that passes through the magnetic pole center and the central axis of the rotor core.
    Type: Application
    Filed: January 17, 2014
    Publication date: December 10, 2015
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Moriyuki HAZEYAMA, Takuma SASAI, Shinsuke KAYANO, Masaya INOUE, Shinji NISHIMURA, Akihiro DAIKOKU
  • Publication number: 20150091407
    Abstract: Permanent magnets that constitute the single magnetic poles are constituted by n permanent magnet segments, the n permanent magnet segments being configured such that shapes and directions of orientation thereof have mirror symmetry relative to a plane that passes through a magnetic pole center and that includes a central axis of the rotor core, and being oriented such that a permanent magnet segment that is further away from the magnetic pole center in a circumferential direction has a smaller angle of orientation, and the permanent magnet segment that is positioned further away from the magnetic pole center in the circumferential direction being produced so as to have an approximately fan-shaped cross-sectional shape in which a radial width is wider than a circumferential width.
    Type: Application
    Filed: May 22, 2012
    Publication date: April 2, 2015
    Applicant: Mitsubishi Electric Corporation
    Inventors: Shinsuke Kayano, Masaya Inoue, Shinji Nishimura, Moriyuki Hazeyama, Takuma Sasai