Patents by Inventor Yuji Hirosawa

Yuji Hirosawa 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: 20240126115
    Abstract: According to one embodiment, an optical control element includes a plurality of lens forming regions along a first direction and a second direction orthogonal to the first direction, each of the lens forming regions includes an annularly shaped second electrode and a circularly shaped first electrode provided on an inner side of the second electrode, a plurality of first wiring lines connected to the first electrodes each include a first stem portion extending in a zigzag shape along the second direction and a plurality of first branch portions extending from the first stem, and each of the first branch portions overlap the plurality of first electrodes, respectively.
    Type: Application
    Filed: October 5, 2023
    Publication date: April 18, 2024
    Applicant: Japan Display Inc.
    Inventors: Shunichi KIMURA, Toshiharu MATSUSHIMA, Jin HIROSAWA, Yuji MAEDE
  • Patent number: 11863020
    Abstract: A rotor core has a magnet insertion hole, an opening formed adjacent to the magnet insertion hole in the circumferential direction, and a thin wall portion formed between the opening and an outer circumference of the rotor core. A stator core has a length in the axial direction shorter than that of the rotor core. The rotor core has a facing region where the rotor core faces the stator core in the radial direction and an overhang region where the rotor core protrudes from the stator core in the axial direction. A distance from the center axis to a portion of the outer circumference located on a radially outer side of the magnet insertion hole is longer in at least part of the overhang region than in the facing region. The minimum width of the thin wall portion in the radial direction is the same in both regions.
    Type: Grant
    Filed: February 21, 2019
    Date of Patent: January 2, 2024
    Assignee: Mitsubishi Electric Corporation
    Inventors: Masahiro Nigo, Yuji Hirosawa, Emi Tsukamoto
  • Publication number: 20230378829
    Abstract: A rotor includes a first rotor core, a plurality of permanent magnets, a plurality of second rotor cores, and a first resin part. Each of the plurality of permanent magnets has a first surface in contact with a first radial-direction-outward-facing surface of the first rotor core and a second surface facing outward in a radial direction. Each of the plurality of second rotor cores has a surface facing inward in the radial direction. The surface of each of the plurality of second rotor cores facing inward in the radial direction is in contact with the second surface of corresponding one of the plurality of permanent magnets. The first resin part is provided between adjoining second rotor cores among the plurality of second rotor cores.
    Type: Application
    Filed: November 19, 2020
    Publication date: November 23, 2023
    Inventors: Yuji HIROSAWA, Masahiro NIGO
  • Publication number: 20230187986
    Abstract: A rotor includes a rotor core having an outer circumference extending in a circumferential direction about an axis and a magnet insertion hole located on an inner side of the outer circumference in a radial direction about the axis, and a permanent magnet inserted in the magnet insertion hole. The rotor core has a flux barrier at an end of the magnet insertion hole in the circumferential direction. At least a part of the flux barrier is located on the outer circumference side of a magnetic pole face of the permanent magnet. In the rotor core, an inter-pole portion is defined on an outer side of the magnet insertion hole in the circumferential direction. A groove portion is formed on the inter-pole portion side of the flux barrier in the circumferential direction. The groove portion is recessed inward in the radial direction from the outer circumference. The groove portion faces the flux barriers in the circumferential direction.
    Type: Application
    Filed: July 28, 2020
    Publication date: June 15, 2023
    Inventors: Yuji HIROSAWA, Masahiro NIGO
  • Publication number: 20230118265
    Abstract: A rotor includes a rotary shaft extending in an axial direction, a first rotor core, a permanent magnet, and a second rotor core. The first rotor core includes a first core part and a second core part arranged in the axial direction and is supported by the rotary shaft. The permanent magnet is attached to the first rotor core. The second rotor core is arranged between the first core part and the second core part. The area of a part where the second rotor core exists is larger than the area of a part where the first rotor core exists when viewed in the axial direction.
    Type: Application
    Filed: March 27, 2020
    Publication date: April 20, 2023
    Inventors: Yuji HIROSAWA, Masahiro NIGO
  • Publication number: 20230091530
    Abstract: A rotor core includes a magnet insertion hole in which a magnet is disposed and an opening connected to the magnet insertion hole. The opening has an outer end edge and an inner end edge facing each other. The opening has a first portion where the outer and inner end edges face each other across a width W1, and a second portion where the outer and inner end edges face each other across a width W2 wider than the width W1. The second portion is located between the first portion and the permanent magnet. A reference line is defined as a straight line obtained by extending a magnetic pole surface of the permanent magnet on a radially outer side a plane perpendicular to the axis. At least a part of the first portion is located on an outer side in the radial direction with respect to the reference line.
    Type: Application
    Filed: April 20, 2020
    Publication date: March 23, 2023
    Inventors: Masahiro NIGO, Yuji HIROSAWA
  • Patent number: 11502634
    Abstract: A driving device includes an inverter to output a voltage to coils, a connection switching unit to switch a connection state of the coils between a Y connection and a delta connection, and a controller. The controller causes the inverter to stop outputting, when the connection state of the coils is the Y connection and a current value of the inverter reaches a first threshold A, or when the connection state of the coils is the delta connection and the current value of the inverter reaches a second threshold B. The first threshold A and the second threshold B satisfy B<?3×A.
    Type: Grant
    Filed: July 25, 2017
    Date of Patent: November 15, 2022
    Assignee: Mitsubishi Electric Corporation
    Inventors: Masahiro Nigo, Yuji Hirosawa
  • Patent number: 11496005
    Abstract: A stator includes a yoke portion, and a tooth portion located inside the yoke portion in a radial direction. A fracture surface ratio of an inner surface of the tooth portion in the radial direction is lower than a fracture surface ratio of a side surface of the yoke portion.
    Type: Grant
    Filed: May 10, 2017
    Date of Patent: November 8, 2022
    Assignee: Mitsubishi Electric Corporation
    Inventors: Yuji Hirosawa, Masahiro Nigo
  • Publication number: 20220239168
    Abstract: A stator is a stator disposed outside a rotor of a motor disposed in a compressor used with a refrigerant containing a substance having a property of causing disproportionation. The stator includes a yoke part and N tooth parts. Each of the N tooth parts includes a tooth end surface to face a rotor. The stator satisfies 0.75?(?1×N)/360?0.97, where ?1 (degrees) is an angle famed by two lines passing through both ends of the tooth end surface and a rotation center of the rotor in a plane perpendicular to an axial direction of the rotor.
    Type: Application
    Filed: July 17, 2019
    Publication date: July 28, 2022
    Inventors: Yuji HIROSAWA, Masahiro NIGO
  • Publication number: 20220200390
    Abstract: A motor includes a rotor rotatable about an axis, a stator having a stator core surrounding the rotor from an outer side in a radial direction about the axis, and an annular shell in which the stator core is fixed. The shell includes a first shell portion facing the stator core in the radial direction and having an inner diameter D1, a second shell portion contacting the stator core in the radial direction and having an inner diameter D2, and a third shell portion protruding from the stator core in a direction of the axis and having an inner diameter D3. The inner diameters D1, D2 and D3 satisfy D1>D2 and D1>D3.
    Type: Application
    Filed: May 20, 2019
    Publication date: June 23, 2022
    Inventors: Yuji HIROSAWA, Masahiro NIGO
  • Publication number: 20220166270
    Abstract: A rotor core has a magnet insertion hole, an opening formed adjacent to the magnet insertion hole in the circumferential direction, and a thin wall portion formed between the opening and an outer circumference of the rotor core. A stator core has a length in the axial direction shorter than that of the rotor core. The rotor core has a facing region where the rotor core faces the stator core in the radial direction and an overhang region where the rotor core protrudes from the stator core in the axial direction. A distance from the center axis to a portion of the outer circumference located on a radially outer side of the magnet insertion hole is longer in at least part of the overhang region than in the facing region. The minimum width of the thin wall portion in the radial direction is the same in both regions.
    Type: Application
    Filed: February 21, 2019
    Publication date: May 26, 2022
    Inventors: Masahiro NIGO, Yuji HIROSAWA, Emi TSUKAMOTO
  • Patent number: 11199351
    Abstract: An air conditioner includes a compressor having a compressor motor including coils, an indoor fan having a fan motor, a connection switching unit that switches a connection state of the coils between a first connection state and a second connection state in which a line voltage is lower than a line voltage in the first connection state, and a controller that controls the compressor motor, the fan motor, and the connection switching unit. The controller provides a stop period during which rotation of the compressor motor stops before the connection switching unit switches the connection state of the coils, and rotates the fan motor for at least a time period within the stop period.
    Type: Grant
    Filed: May 10, 2017
    Date of Patent: December 14, 2021
    Assignee: Mitsubishi Electric Corporation
    Inventors: Yuji Hirosawa, Masahiro Nigo
  • Patent number: 11018535
    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: Grant
    Filed: November 2, 2015
    Date of Patent: May 25, 2021
    Assignee: Mitsubishi Electric Corporation
    Inventors: Masahiro Nigo, Yuji Hirosawa, Ryukichi Kijima
  • Patent number: 10965237
    Abstract: A driving device includes a connection switching unit to switch a connection state of coils between a first connection state and a second connection state in which a line voltage is lower than in the first connection state, a controller to control a motor and the connection switching unit, and a rotation speed detector to detect a rotation speed of the motor. When the connection state of the coils is the first connection state and the rotation speed detected by the rotation speed detector becomes higher than or equal to a first rotation speed, the controller causes the motor to rotate at a second rotation speed higher than the first rotation speed, and then causes the connection switching unit to switch the connection state of the coils from the first connection state to the second connection state.
    Type: Grant
    Filed: July 25, 2017
    Date of Patent: March 30, 2021
    Assignee: Mitsubishi Electric Corporation
    Inventors: Masahiro Nigo, Yuji Hirosawa
  • Patent number: 10951139
    Abstract: A driving device includes a connection switching unit that switches connection condition of a coil between Y connection and delta connection, an inverter, and a control device that controls a carrier frequency of the inverter. The carrier frequency is set at a first carrier frequency when the connection condition of the coil is the Y connection. The carrier frequency is set at a second carrier frequency when the connection condition of the coil is the delta connection.
    Type: Grant
    Filed: July 28, 2017
    Date of Patent: March 16, 2021
    Assignee: Mitsubishi Electric Corporation
    Inventors: Yuji Hirosawa, Masahiro Nigo
  • Patent number: 10916977
    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: Grant
    Filed: October 11, 2016
    Date of Patent: February 9, 2021
    Assignee: Mitsubishi Electric Corporation
    Inventors: Masahiro Nigo, Yuji Hirosawa
  • Patent number: 10763717
    Abstract: A stator core includes a first core portion including a plurality of first plates stacked in a first direction; a second core portion including a plurality of second plates stacked in the first direction; and a third core portion including a plurality of third plates stacked in at least one direction orthogonal to the first direction, the third core portion being sandwiched between the first core portion and the second core portion. The third core portion has a yoke portion formed of a subset of the plurality of third plates stacked in a second direction orthogonal to the first direction.
    Type: Grant
    Filed: September 13, 2016
    Date of Patent: September 1, 2020
    Assignee: Mitsubishi Electric Corporation
    Inventors: Yuji Hirosawa, Masahiro Nigo
  • Publication number: 20200186073
    Abstract: A driving device includes a connection switching unit to switch a connection state of coils between a first connection state and a second connection state in which a line voltage is lower than in the first connection state, a controller to control a motor and the connection switching unit, and a rotation speed detector to detect a rotation speed of the motor. When the connection state of the coils is the first connection state and the rotation speed detected by the rotation speed detector becomes higher than or equal to a first rotation speed, the controller causes the motor to rotate at a second rotation speed higher than the first rotation speed, and then causes the connection switching unit to switch the connection state of the coils from the first connection state to the second connection state.
    Type: Application
    Filed: July 25, 2017
    Publication date: June 11, 2020
    Inventors: Masahiro NIGO, Yuji HIROSAWA
  • Publication number: 20200177114
    Abstract: A driving device includes a connection switching unit that switches connection condition of a coil between Y connection and delta connection, an inverter, and a control device that controls a carrier frequency of the inverter. The carrier frequency is set at a first carrier frequency when the connection condition of the coil is the Y connection. The carrier frequency is set at a second carrier frequency when the connection condition of the coil is the delta connection.
    Type: Application
    Filed: July 28, 2017
    Publication date: June 4, 2020
    Inventors: Yuji HIROSAWA, Masahiro NIGO
  • Publication number: 20200144951
    Abstract: A driving device includes an inverter to output a voltage to coils, a connection switching unit to switch a connection state of the coils between a Y connection and a delta connection, and a controller. The controller causes the inverter to stop outputting, when the connection state of the coils is the Y connection and a current value of the inverter reaches a first threshold A, or when the connection state of the coils is the delta connection and the current value of the inverter reaches a second threshold B. The first threshold A and the second threshold B satisfy B<?3×A.
    Type: Application
    Filed: July 25, 2017
    Publication date: May 7, 2020
    Inventors: Masahiro NIGO, Yuji HIROSAWA