Patents by Inventor Masahiro Nigo

Masahiro Nigo 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: 20190245470
    Abstract: A driving device drives a motor having coils. The driving device includes a connection switching unit to switch a connection state of the coils, a temperature sensor to detect a room temperature, and a controller to switch the connection state of the coils based on a detected temperature by the temperature sensor.
    Type: Application
    Filed: October 31, 2016
    Publication date: August 8, 2019
    Inventor: Masahiro NIGO
  • Publication number: 20190245471
    Abstract: An air conditioner includes a signal receiving unit to receive an operation instruction signal, a compressor including a motor including coils, an inverter connected to the coils, a connection switching unit to switch a connection state of the coils between a first connection state and a second connection state, and a controller to control the inverter and the connection switching unit. When the signal receiving unit receives an operation stop signal, the connection switching unit switches the connection state of the coils from the first connection state to the second connection state.
    Type: Application
    Filed: October 31, 2016
    Publication date: August 8, 2019
    Inventor: Masahiro NIGO
  • Publication number: 20190229564
    Abstract: A stator includes: a stator core including a first core part formed by at least one first sheet and a second core part provided on a side face of the first core part and formed by at least one second sheet; and a winding wound around an outer periphery of the first core part and the second core part.
    Type: Application
    Filed: October 11, 2016
    Publication date: July 25, 2019
    Inventors: Masahiro NIGO, Yuji HIROSAWA
  • Patent number: 10284030
    Abstract: A permanent magnet embedded electric motor includes a stator core disposed inside the frame and having a back yoke and a plurality of magnetic pole teeth; a rotor disposed on an inner diameter side of the plurality of magnetic pole teeth; and compression sections in which compression stress higher than compression stress occurring in the back yoke due to pressing force generated between the frame and the back yoke occurs. A compression section group having a set of two or more compression sections and of the plurality of compression sections is disposed on an outer circumferential section of the stator core. A sum of the rotating direction widths of the plurality of compression sections constituting the compression section group is smaller than a radial direction thickness of the frame.
    Type: Grant
    Filed: September 1, 2014
    Date of Patent: May 7, 2019
    Assignee: Mitsubishi Electric Corporation
    Inventors: Masahiro Nigo, Kazuchika Tsuchida, Kazuhiko Baba
  • Publication number: 20190081520
    Abstract: A stator includes a first core including a plurality of non-oriented electromagnetic steel sheets stacked in layers and having an insertion hole penetrating the plurality of non-oriented electromagnetic steel sheets in an axial direction of the stator and a second core arranged in the insertion hole and including a plurality of oriented electromagnetic steel sheets stacked in layers. The first core has a side wall part adjoining a side surface of the second core extending in the axial direction of the stator, and the side wall part has an opening part that exposes the side surface of the second core.
    Type: Application
    Filed: May 30, 2016
    Publication date: March 14, 2019
    Inventors: Kazuhiko BABA, Masahiro NIGO
  • Publication number: 20190081521
    Abstract: A stator includes a first core including a plurality of non-oriented electromagnetic steel sheets that is stacked and having an insertion hole penetrating the plurality of non-oriented electromagnetic steel sheets in an axial direction of the stator and a second core arranged in the insertion hole and including a plurality of oriented electromagnetic steel sheets that is stacked. The first core has a thin-wall part adjoining the second core, and a conditional expression of 0.5tm?ta?2tm is satisfied, where ta denotes a thickness of the thin-wall part when the first core is viewed in the axial direction and tm denotes a sheet thickness of one non-oriented electromagnetic steel sheet in the plurality of non-oriented electromagnetic steel sheets.
    Type: Application
    Filed: May 30, 2016
    Publication date: March 14, 2019
    Inventors: Kazuhiko BABA, Masahiro NIGO
  • Publication number: 20190081519
    Abstract: A stator includes a first core and a second core. The first core has a yoke extending in a circumferential direction about an axis line and having a second insertion hole, and a tooth extending from the yoke in a direction toward the axis line and having a first insertion hole. The second core has a first part disposed in the first insertion hole and a second part disposed in the second insertion hole and formed of amorphous metal or nanocrystal metal.
    Type: Application
    Filed: May 30, 2016
    Publication date: March 14, 2019
    Inventors: Kazuhiko BABA, Masahiro NIGO
  • Publication number: 20190044400
    Abstract: A rotor includes a cylindrical a rotor core having a plurality of magnet insertion holes extending along a central axis of the cylindrical shape and permanent magnets inserted into the magnet insertion holes, respectively. A slit extending along the central axis is provided between an outer circumferential surface of the rotor core and at least one of the magnet insertion holes. The slit inner lines extend toward the outer circumferential surface of the rotor core from the apex of the slit, the apex being located on a side of the magnet insertion holes. The slit outer line connects side ends of the slit inner lines located on a side opposite to the apex.
    Type: Application
    Filed: October 27, 2015
    Publication date: February 7, 2019
    Inventors: Kazuchika TSUCHIDA, Masahiro NIGO
  • Publication number: 20190006896
    Abstract: In an electric motor, a first magnet and a second magnet are accommodated in magnet accommodating apertures of a rotor core. On outer circumferential core portions that exist on a radially outer side of the magnet accommodating apertures, two slits as a pair of first slits, and two slits that are respectively adjacent to each of the first slits are disposed circumferentially outside the pair of first slits as a pair of second slits. The outer circumferential core portions include: a first magnetic portion that exists between the pair of first slits; and a pair of second magnetic portions that respectively exist between the first slits and the second slits. An inter-magnet space portion that exists between the first magnet and the second magnet is positioned within a range of the first magnetic portion in the circumferential direction of the rotor.
    Type: Application
    Filed: February 12, 2016
    Publication date: January 3, 2019
    Inventors: Kazuhiko BABA, Masahiro NIGO, Kazuchika TSUCHIDA, Atsushi ISHIKAWA
  • Publication number: 20180358846
    Abstract: A motor includes a stator core, a rotor core that is disposed on an inner side of the stator core and has a plurality of magnet holes arrayed in a circumferential direction, and a plurality of permanent magnets respectively disposed in the magnet holes. The stator core is constructed by a plurality of plates formed from a first magnetic material, each of which has a first thickness. The rotor core is constructed by a plurality of plates formed from a second magnetic material, each of which has a second thickness. The first thickness is smaller than the second thickness, and a silicon content rate of the first soft magnetic material is larger than a silicon content rate of the second soft magnetic material.
    Type: Application
    Filed: January 20, 2016
    Publication date: December 13, 2018
    Inventors: Kazuhiko BABA, Masahiro NIGO
  • Patent number: 10135307
    Abstract: An end of each of slits of a rotor on a magnet insertion hole side has a triangular shape. A slit inner-side line of each of the slits includes an apex and a pair of side ends. An interval between each of the pair of side ends and the magnet insertion hole is larger than an interval between the apex and the magnet insertion hole, and an interval between the apex and the magnet insertion hole is larger than a plate thickness of each of steel plates forming a rotor core.
    Type: Grant
    Filed: April 28, 2014
    Date of Patent: November 20, 2018
    Assignee: Mitsubishi Electric Corporation
    Inventors: Kazuchika Tsuchida, Tomoaki Oikawa, Masahiro Nigo, Naohiro Oketani
  • Patent number: 10116176
    Abstract: In a permanent magnet embedded electric motor, a rotor iron core of a rotor disposed on an inner diameter side of a stator includes: a plurality of first slits that are formed on a radial direction outer side of a magnet insertion hole, and communicate with the magnet insertion hole; a plurality of second slits formed at positions opposed to and spaced apart from the first slits; inter-slit iron core portions formed between the first slits and the second slits; outer side iron core portions formed between the second slits and an outer circumferential surface of the rotor iron core; space portions communicating with rotating direction end portions of the magnet insertion hole; and thin iron core portions that are formed between the space portions and the outer circumferential surface of the rotor iron core, and extend in a rotating direction.
    Type: Grant
    Filed: October 7, 2014
    Date of Patent: October 30, 2018
    Assignee: Mitsubishi Electric Corporation
    Inventors: Kazuhiko Baba, Masahiro Nigo, Atsushi Ishikawa
  • Patent number: 10103588
    Abstract: An interior permanent magnet motor includes a stator and a rotor. The rotor includes a rotor core having a plurality of magnet receiving holes, and a plurality of permanent magnets are received in each of the magnet receiving holes. A plurality of slits are formed at a part between an outer peripheral surface of the rotor and an outer-side defining line of the each of the magnet receiving holes. At least one space portion is secured between the plurality of permanent magnets, and the space portion is opposed to any one of the plurality of slits in a direction parallel to a magnetic pole center line.
    Type: Grant
    Filed: December 5, 2013
    Date of Patent: October 16, 2018
    Assignee: Mitsubishi Electric Corporation
    Inventors: Kazuhiko Baba, Masahiro Nigo, Kazuchika Tsuchida, Atsushi Ishikawa
  • Patent number: 10090743
    Abstract: In an interior permanent magnet motor, a magnet insertion hole of a rotor core is curved into an arc shape, and a convex portion side of the arc shape is arranged on a center side of a rotor. The magnet insertion hole has a first line, a second line, and a pair of third lines. The first line is located on the radially outer side of the second line. Each of the third lines connects the first line and the second line to each other. The first line includes an arc portion and a pair of concave portions. Each of the concave portions is located at an end of the arc portion of the first line.
    Type: Grant
    Filed: April 16, 2015
    Date of Patent: October 2, 2018
    Assignee: Mitsubishi Electric Corporation
    Inventors: Masahiro Nigo, Kazuhiko Baba, Kazuchika Tsuchida
  • Patent number: 10084354
    Abstract: An interior permanent magnet motor capable of increasing an output of a motor without reducing torque by increasing demagnetization resistance. The interior permanent magnet motor includes a rotator including a rotator core, and a stator. The rotator core includes a plurality of magnet accommodating holes and a plurality of permanent magnets. The thickness in the short-side direction of each of the magnet accommodating holes is minimum at the center portion of the magnetic pole, and is gradually increased toward the radially outer side of the rotator core. At least the thickness in the short-side direction of the permanent magnet at the center portion of the magnetic pole is equal to the thickness in the short-side direction of the magnet accommodating hole at the center portion of the magnetic pole.
    Type: Grant
    Filed: September 20, 2013
    Date of Patent: September 25, 2018
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Kazuhiko Baba, Masahiro Nigo, Kazuchika Tsuchida
  • Publication number: 20180254676
    Abstract: A permanent-magnet-embedded electric motor includes an annular stator, and an annular rotor iron core disposed on an inner side of the stator and having a plurality of magnet insertion holes aligned in a circumferential direction of the stator. Each of the magnet insertion holes has a pair of recess portions on an outer side surface in the radial direction of the stator, the pair of recess portions are respectively disposed on one end portion and on another end portion of the outer side surface in the circumferential direction of the stator, and a plurality of permanent magnets respectively inserted in the magnet insertion holes. Each of the recess portions has a depth of from 10% to 40% of the thickness of each of the permanent magnets in the radial direction of the stator.
    Type: Application
    Filed: January 7, 2016
    Publication date: September 6, 2018
    Applicant: Mitsubishi Electric Corporation
    Inventors: Masahiro NIGO, Kazuchika TSUCHIDA
  • Publication number: 20180248419
    Abstract: A stator includes a winding and a plurality of split core parts arranged annularly in a circumferential direction around an axis line. Each of the plurality of split core parts includes a yoke part, a tooth part, a connection part including a curved surface, and a first insulator provided on an end part of the tooth part. The first insulator includes a first protruding part protruding beyond the curved surface.
    Type: Application
    Filed: November 4, 2015
    Publication date: August 30, 2018
    Inventors: Masahiro NIGO, Shuichi KITANO, Yasusi SHOJI
  • Publication number: 20180248426
    Abstract: A motor includes a stator, a rotor including a rotor core having a magnet insertion hole, and a plurality of permanent magnets disposed in the magnet insertion hole of the rotor core and having two permanent magnets adjacent to each other. The rotor core has a first magnet holding portion in the magnet insertion hole, and a second magnet holding portion at an end of the magnet insertion hole in a circumferential direction. The rotor core has a plurality of electromagnetic steel sheets stacked in an axial direction. Relationships A>B and A>C are satisfied, where a number of the plurality of electromagnetic steel sheets is represented by A, a number of electromagnetic steel sheets having the first magnet holding portions is represented by B, and a number of electromagnetic steel sheets having the second magnet holding portions is represented by C.
    Type: Application
    Filed: October 30, 2015
    Publication date: August 30, 2018
    Applicant: Mitsubishi Electric Corporation
    Inventors: Masahiro NIGO, Kazuchika TSUCHIDA, Ryukichi KIJIMA
  • Publication number: 20180248428
    Abstract: A motor includes a stator and a rotor provided inside the stator. The rotor includes a rotor core having a magnet insertion hole and two permanent magnets disposed in the magnet insertion hole. The rotor core has a first magnet holding portion disposed between the two permanent magnets and holding the two permanent magnets, an opening disposed on an inner side of the first magnet holding portion in a radial direction of the rotor core, and a center hole disposed at a center of the rotor core in the radial direction. A distance from the opening to the magnet insertion hole is shorter than a distance from the opening to the center hole.
    Type: Application
    Filed: November 2, 2015
    Publication date: August 30, 2018
    Inventors: Masahiro NIGO, Yuji HIROSAWA, Ryukichi KIJIMA
  • Publication number: 20180212482
    Abstract: A permanent magnet embedded motor includes a cylindrical stator core disposed on an inner side of a cylindrical frame and configured by stacking a first annular core and a second annular core disposed to be adjacent to the first annular core in an axial direction of the frame, and a rotor disposed on an inner side of the stator core. The second annular core is fixed to the first annular core by using swaging portions formed in the second annular core, and adjacent first yokes are in contact with each other, while adjacent second yokes are separated from each other.
    Type: Application
    Filed: August 21, 2015
    Publication date: July 26, 2018
    Inventors: Masahiro NIGO, Kazuchika TSUCHIDA, Sadami OKUGAWA, Yoshinori IWANABE