Patents by Inventor Akira Mima

Akira Mima 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: 20240166104
    Abstract: A vehicle seat includes a support leg connected to a floor to be pivotable about a first axis extending in a horizontal direction; a seat cushion connected to the support leg to be pivotable about a second axis which is parallel to the first axis; a first coupling device provided on the support leg and configured to be detachably coupled with a first coupling part provided on the floor; and a second coupling device provided on the seat cushion and configured to be detachably coupled with a second coupling part provided on the floor. The seat cushion is movable between a stowed position in which the seat cushion is in a lowest position, a first use position in which the first coupling device is coupled with the first coupling part, and a second use position in which the second coupling device is coupled with the second coupling part.
    Type: Application
    Filed: March 30, 2022
    Publication date: May 23, 2024
    Inventors: Kohei TAGUCHI, Takako MIYOSHI, Takayoshi ITO, Kazuya MIYAWAKI, Kazuaki MIMA, Yuki YOSHIOKA, Akira MIYOSHI, Tomoyuki KURIMOTO, Keiichi KITAYAMA, Yasuhiro FURUICHI
  • Publication number: 20240136936
    Abstract: Provided are a positive electrode terminal and a negative electrode terminal being terminals of a capacitor element; a positive electrode conductor plate connected to the positive electrode terminal; a negative electrode conductor plate connected to the negative electrode terminal; and a power conversion module connected to the two conductor plates. The positive electrode terminal and the negative electrode terminal are formed along an arrangement direction of the capacitor element. The positive electrode conductor plate and the negative electrode conductor plate form a laminated conductor portion in which the positive electrode conductor plate and the negative electrode conductor plate have respective main surfaces disposed, to face the main surface of the capacitor element, and are laminated to each other.
    Type: Application
    Filed: September 29, 2021
    Publication date: April 25, 2024
    Inventors: Akira MIMA, Takeshi TOKUYAMA, Junpei KUSUKAWA, Takashi HIRAO
  • Publication number: 20240014088
    Abstract: Provided is a compact and highly reliable power semiconductor device that prevents partial discharge originating from voids generated by the entering of water vapor from the exterior of the semiconductor device through a sealing resin or voids generated between a main terminal and the sealing resin when the main terminal is heated. The power semiconductor device comprises an insulating substrate, a semiconductor element provided on a front surface of the insulating substrate, and a gel-like first insulation material for sealing the semiconductor element. The power semiconductor device further includes a plate-shaped terminal for electrically connecting the semiconductor element and an external equipment, and an entire portion of the plate-shaped terminal surrounded by the first insulating material is covered with a second insulating material having a hardness greater than that of the first insulating material.
    Type: Application
    Filed: November 25, 2021
    Publication date: January 11, 2024
    Applicant: Hitachi Power Semiconductor Device, Ltd.
    Inventors: Junpei Kusukawa, Eiichi Ide, Akira Mima
  • Publication number: 20230148137
    Abstract: There has been a problem that when a value of a current flowing through a thermistor increases, a voltage drop generated in the thermistor increases, and variations occur in a clamp voltage. A semiconductor device includes: a switching element that is on-off controlled; and a surge voltage protection circuit connected between a positive electrode side terminal of the switching element and a control terminal of the switching element. The surge voltage protection circuit includes a first Zener diode, a second Zener diode connected in series with the first Zener diode, and a temperature characteristic compensating element having a temperature coefficient different in polarity from the first Zener diode and the second Zener diode and connected in parallel with the second Zener diode.
    Type: Application
    Filed: January 15, 2021
    Publication date: May 11, 2023
    Inventors: Takahiro ARAKI, Akira MIMA, Noriyuki MAEKAWA
  • Publication number: 20230059509
    Abstract: An object of the present invention is to provide a power conversion device configured to attain suppression of heat concentration and miniaturization of the device. The power conversion device 40 includes a power module 17 for converting dc power into ac power, a first circuit substrate (power circuit substrate) 16 including a capacitor 31 for smoothing the dc power, and a casing 20 for storing the power module 17 and the first circuit substrate 16. Either the first circuit substrate 16 or the power module 17 is disposed on an inner surface 20bb of a side wall 20b having an outer wall surface 20ba of the casing 20, and the other is disposed on a predetermined inner wall surface 20a of the casing 20 to form an angle with the inner surface 20bb.
    Type: Application
    Filed: October 23, 2020
    Publication date: February 23, 2023
    Inventors: Akira MIMA, Yukio HATTORI, Eiichi IDE
  • Publication number: 20200220434
    Abstract: A first wall portion and a second wall portion of a shield member are provided on a radially outer side of a rotation axis of a motor shaft with respect to a first magnetic sensor in a region other than a region of overlapping the first magnetic sensor on a plane orthogonal to the rotation axis.
    Type: Application
    Filed: September 5, 2018
    Publication date: July 9, 2020
    Applicant: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Makoto KIMURA, Takuro KANAZAWA, Akira MIMA
  • Patent number: 10141861
    Abstract: To improve accessibility with respect to a power conversion unit in a power converter. The power converter includes a circuit connection part including a positive electrode conductor, a negative electrode conductor and an AC conductor, a power semiconductor module positioned in a particular direction with respect to the circuit connection part and connected to the positive electrode conductor, the negative electrode conductor and the AC conductor and a capacitor positioned in the particular direction with respect to the circuit connection part and connected to the positive electrode conductor and the negative electrode conductor. The positive electrode conductor is connected to a positive electrode conductor of another power conversion unit through a unit connection part positioned in an opposite direction of the particular direction with respect to the circuit connection part.
    Type: Grant
    Filed: January 26, 2018
    Date of Patent: November 27, 2018
    Assignee: Hitachi, Ltd.
    Inventors: Yukio Hattori, Hiroshi Kamizuma, Daisuke Matsumoto, Akira Mima, Tetsuya Kawashima, Yuuichi Mabuchi
  • Patent number: 10014793
    Abstract: An imbalance of control signals between two power semiconductor elements is reduced. A first power semiconductor module and a second power semiconductor module are arranged in a predetermined direction along a surface of a control signal wiring circuit board, each of longitudinal directions of the first power semiconductor module and the second power semiconductor module along the surface of the control signal wiring circuit board is a predetermined direction, and, in a first control signal wiring, a distance between an external control signal terminal and a second control signal terminal is equal to a distance between the external control signal terminal and a first control signal terminal.
    Type: Grant
    Filed: March 10, 2014
    Date of Patent: July 3, 2018
    Assignee: Hitachi, Ltd.
    Inventors: Akira Mima, Yukio Hattori, Tetsuya Kawashima, Yuichi Mabuchi, Daisuke Matsumoto, Hiroshi Kamiduma
  • Patent number: 10008953
    Abstract: An uninterruptible power-supply system is a power converter having a PN laminated bus bar and a plurality of power conversion units and supplying power from a commercial power supply via a converter and an inverter. The power conversion units each have positive side terminals connected to each other and negative side terminals connected to each other through the PN laminated bus bar. At least one power conversion unit constitutes a phase of the converter. At least another one power conversion unit constitutes a phase of the inverter and has the positive side terminal lying adjacent to and connected through the PN laminated bus bar to the positive side terminal of the corresponding power conversion unit constituting the phase of the converter and the negative side terminal lying adjacent to and connected to the negative side terminal of the corresponding power conversion unit constituting the phase of the converter.
    Type: Grant
    Filed: May 7, 2014
    Date of Patent: June 26, 2018
    Assignee: Hitachi, Ltd.
    Inventors: Hiroshi Kamizuma, Yukio Hattori, Tetsuya Kawashima, Akira Mima, Daisuke Matsumoto, Yuuichi Mabuchi
  • Publication number: 20180152117
    Abstract: To improve accessibility with respect to a power conversion unit in a power converter. The power converter includes a circuit connection part including a positive electrode conductor, a negative electrode conductor and an AC conductor, a power semiconductor module positioned in a particular direction with respect to the circuit connection part and connected to the positive electrode conductor, the negative electrode conductor and the AC conductor and a capacitor positioned in the particular direction with respect to the circuit connection part and connected to the positive electrode conductor and the negative electrode conductor. The positive electrode conductor is connected to a positive electrode conductor of another power conversion unit through a unit connection part positioned in an opposite direction of the particular direction with respect to the circuit connection part.
    Type: Application
    Filed: January 26, 2018
    Publication date: May 31, 2018
    Inventors: Yukio HATTORI, Hiroshi KAMIZUMA, Daisuke MATSUMOTO, Akira MIMA, Tetsuya KAWASHIMA, Yuuichi MABUCHI
  • Patent number: 9948201
    Abstract: A module of conversion circuit includes a High side IGBT, a Low side IGBT connected in series to the High side IGBT, a first terminal connected to the High side IGBT, a second terminal connected to the Low side IGBT, a capacitor connected to the first terminal and the second terminal, and a third terminal connected to a connection point between the High side IGBT and the Low side IGBT. A fourth terminal is engaged with the first terminal. A fifth terminal is engaged with the second terminal. A sixth terminal is engaged with the third terminal. The first and second terminals have at portions thereof between front edges and rear edges high-resistance parts having higher resistance than other portions.
    Type: Grant
    Filed: February 22, 2016
    Date of Patent: April 17, 2018
    Assignee: Hitachi, Ltd.
    Inventors: Shinji Shirakawa, Hiroshi Kamizuma, Daisuke Matsumoto, Akira Mima, Yukio Hattori
  • Patent number: 9917529
    Abstract: To improve accessibility with respect to a power conversion unit in a power converter. The power converter includes a circuit connection part including a positive electrode conductor, a negative electrode conductor and an AC conductor, a power semiconductor module positioned in a particular direction with respect to the circuit connection part and connected to the positive electrode conductor, the negative electrode conductor and the AC conductor and a capacitor positioned in the particular direction with respect to the circuit connection part and connected to the positive electrode conductor and the negative electrode conductor. The positive electrode conductor is connected to a positive electrode conductor of another power conversion unit through a unit connection part positioned in an opposite direction of the particular direction with respect to the circuit connection part.
    Type: Grant
    Filed: March 27, 2014
    Date of Patent: March 13, 2018
    Assignee: Hitachi, Ltd.
    Inventors: Yukio Hattori, Hiroshi Kamizuma, Daisuke Matsumoto, Akira Mima, Tetsuya Kawashima, Yuuichi Mabuchi
  • Patent number: 9906154
    Abstract: The present invention reduces the footprint of a power conversion device. A first power semiconductor module and a second power semiconductor module are connected to a positive conductor, a negative conductor, and an alternating-current conductor. An external alternating-current terminal, the first power semiconductor module, the second power semiconductor module, a capacitor, and an external direct-current terminal including an external positive terminal and an external negative terminal are arrayed on a straight line extending in the longitudinal direction of a circuit connection section. The external alternating-current terminal is disposed at one longitudinal end of the circuit connection section. The external direct-current terminal is disposed at the other longitudinal end of the circuit connection section.
    Type: Grant
    Filed: March 2, 2015
    Date of Patent: February 27, 2018
    Assignee: Hitachi, Ltd.
    Inventors: Yukio Hattori, Hiroshi Kamizuma, Tetsuya Kawashima, Akira Mima, Daisuke Matsumoto, Yuuichi Mabuchi
  • Publication number: 20180006573
    Abstract: An electrical power conversion unit is provided with: a circuit connecting part which includes a positive electrode conductor, a negative electrode conductor, and an alternating current conductor; a power semiconductor module connected to a specific side of the circuit connecting part; a fin that extends to the opposite side of the circuit connecting part with respect to the power semiconductor module; and a capacitor disposed at one end in the lengthwise direction of the circuit connecting part. A space in which a cooling fan is disposed is formed by an extending part and the fin, when the extending part is defined as a region, of the circuit connecting part, other than the portion at which the fin projects to the circuit connecting part, such region including one end that is opposite, via the fin, the one end where the capacitor is present.
    Type: Application
    Filed: March 4, 2015
    Publication date: January 4, 2018
    Inventors: Yukio HATTORI, Hiroshi KAMIZUMA, Daisuke MATSUMOTO, Akira MIMA, Ryouhei MIYAGAWA
  • Patent number: 9807913
    Abstract: A cooling structure of a heating element includes: the heating element having at least one cooling surface from which a plurality of pin fins project; a heat receiving plate which has a shape complying with the cooling surface and in which holes are formed at positions facing each pin fin, each pin fin being movably inserted into the holes; a cooler which has a pair of clamping members that sandwich therebetween the heating element and the heat receiving plate while pressing the heating element and the heat receiving plate, and which cools the heat receiving plate; and a space securing part which is provided on the heat receiving plate and suppresses a distance between the pair of clamping members so as not to apply a pressing force by the clamping members to the heating element.
    Type: Grant
    Filed: August 8, 2016
    Date of Patent: October 31, 2017
    Assignee: Hitachi, Ltd.
    Inventors: Daisuke Matsumoto, Akira Mima, Tetsuya Kawashima, Yuuichi Mabuchi, Yukio Hattori, Hiroshi Kamizuma, Ryouhei Miyagawa, Tomonori Ichikawa
  • Patent number: 9755526
    Abstract: A power converter that can be made compact and lightweight is provided. The power converter includes a control circuit power supply, a power semiconductor module that includes power conversion elements, a control circuit board that operates with power from the control circuit power supply and controls the power conversion elements, and a capacitor connected to the power conversion elements. In the power converter, the control circuit power supply charges the capacitor through the control circuit board. With this configuration, hot swapping of the power converter from the converter system can be performed. A boosting circuit may boost voltage of the control circuit power supply to charge the capacitor.
    Type: Grant
    Filed: February 16, 2016
    Date of Patent: September 5, 2017
    Assignee: Hitachi, Ltd.
    Inventors: Akira Mima, Hiroshi Kamizuma
  • Publication number: 20170040906
    Abstract: The present invention reduces the footprint of a power conversion device. A first power semiconductor module and a second power semiconductor module are connected to a positive conductor, a negative conductor, and an alternating-current conductor. An external alternating-current terminal, the first power semiconductor module, the second power semiconductor module, a capacitor, and an external direct-current terminal including an external positive terminal and an external negative terminal are arrayed on a straight line extending in the longitudinal direction of a circuit connection section. The external alternating-current terminal is disposed at one longitudinal end of the circuit connection section. The external direct-current terminal is disposed at the other longitudinal end of the circuit connection section.
    Type: Application
    Filed: March 2, 2015
    Publication date: February 9, 2017
    Inventors: Yukio HATTORI, Hiroshi KAMIZUMA, Tetsuya KAWASHIMA, Akira MIMA, Daisuke MATSUMOTO, Yuuichi MABUCHI
  • Publication number: 20170033593
    Abstract: An uninterruptible power-supply system is a power converter having a PN laminated bus bar and a plurality of power conversion units and supplying power from a commercial power supply via a converter and an inverter. The power conversion units each have positive side terminals connected to each other and negative side terminals connected to each other through the PN laminated bus bar. At least one power conversion unit constitutes a phase of the converter. At least another one power conversion unit constitutes a phase of the inverter and has the positive side terminal lying adjacent to and connected through the PN laminated bus bar to the positive side terminal of the corresponding power conversion unit constituting the phase of the converter and the negative side terminal lying adjacent to and connected to the negative side terminal of the corresponding power conversion unit constituting the phase of the converter.
    Type: Application
    Filed: May 7, 2014
    Publication date: February 2, 2017
    Inventors: Hiroshi KAMIZUMA, Yukio HATTORI, Tetsuya KAWASHIMA, Akira MIMA, Daisuke MATSUMOTO, Yuuichi MABUCHI
  • Patent number: 9532489
    Abstract: A power conversion device capable of reducing a temperature variation between a plurality of semiconductor modules is provided. The power conversion device comprises condensers 121, 122, a plurality of semiconductor modules 101, 102, heat dissipation units 103 to 109, a bus bar 140 connecting the condensers 121, 122 with the plurality of the semiconductor modules 101, 102, and a ventilation unit having cool wind blow. The power conversion module has features that the plurality of semiconductor modules 101, 102 are arranged apart from the condensers 121, 122 and in a line in a longitudinal direction of the bus bar 140 and that the cool wind 150 blows in a direction from the condensers 121, 122 toward the plurality of semiconductor modules 101, 102 that are mounted.
    Type: Grant
    Filed: June 25, 2015
    Date of Patent: December 27, 2016
    Assignee: Hitachi, Ltd.
    Inventors: Yuuichi Mabuchi, Tetsuya Kawashima, Daisuke Matsumoto, Akira Mima, Yukio Hattori, Hiroshi Kamizuma
  • Publication number: 20160373017
    Abstract: An imbalance of control signals between two power semiconductor elements is reduced. A first power semiconductor module and a second power semiconductor module are arranged in a predetermined direction along a surface of a control signal wiring circuit board, each of longitudinal directions of the first power semiconductor module and the second power semiconductor module along the surface of the control signal wiring circuit board is a predetermined direction, and, in a first control signal wiring, a distance between an external control signal terminal and a second control signal terminal is equal to a distance between the external control signal terminal and a first control signal terminal.
    Type: Application
    Filed: March 10, 2014
    Publication date: December 22, 2016
    Inventors: Akira MIMA, Yukio HATTORI, Tetsuya KAWASHIMA, Yuichi MABUCHI, Daisuke MATSUMOTO, Hiroshi KAMIDUMA