Patents by Inventor Kazufumi Tanaka

Kazufumi Tanaka 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: 20240055171
    Abstract: A transformer includes a core group and a winding group. Each of a plurality of winding layers penetrates through a plurality of closed magnetic circuits formed by a plurality of cores. When viewed from the top, the cores are disposed with spacing along conductor wires through which current of the winding layers flows, and the winding layers are disposed side by side from the inside to the outside with spacing along a direction intersecting the direction of current. With this configuration, a coil device with good heat dissipation performance, compact size, high efficiency, and low costs can be provided.
    Type: Application
    Filed: February 2, 2022
    Publication date: February 15, 2024
    Applicants: Mitsubishi Electric Corporation, Nunome Electric Co., Ltd.
    Inventors: Takashi KUMAGAI, Kazuaki FUKUI, Yoshiaki YAMAMOTO, Kazufumi TANAKA, Kenji ASAI, Kazuya OHASHI, Koji ISHIHARA
  • Patent number: 11349410
    Abstract: A series multiplex inverter includes a power conversion unit, a phase difference selection unit, a drive signal generation unit, and a drive signal output unit. The phase difference selection unit selects, from among a plurality of phase difference candidates, the phase difference between rectangular wave voltages from a plurality of single-phase inverters. The drive signal generation unit generates a plurality of drive signals that causes the different single-phase inverters to output a plurality of rectangular wave voltages sequentially out of phase by the phase difference selected by the phase difference selection unit. The drive signal output unit outputs the plurality of drive signals generated by the drive signal generation unit to the plurality of single-phase inverters.
    Type: Grant
    Filed: January 30, 2018
    Date of Patent: May 31, 2022
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Kazufumi Tanaka, Kazutoshi Kurahashi, Yoshiaki Yamamoto, Shuta Ishikawa
  • Patent number: 11183948
    Abstract: A series multiplex inverter includes a power conversion unit, a drive signal generation unit, and a drive signal output unit. The drive signal generation unit generates n drive signals that cause different single-phase inverters of n single-phase inverters to output n rectangular wave voltages sequentially out of phase, where n is an integer of three or more. The drive signal output unit outputs the n drive signals to the n single-phase inverters in rotation that shifts, by p every m-fold time of half an output voltage period of the power conversion unit, the single-phase inverters corresponding one-to-one to the n drive signals in a combination of the n drive signals with different single-phase inverters of the n single-phase inverters, where m is a natural number and p is a natural number relatively prime to n or one.
    Type: Grant
    Filed: January 29, 2018
    Date of Patent: November 23, 2021
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Kazufumi Tanaka, Kazutoshi Kurahashi, Yoshiaki Yamamoto, Shuta Ishikawa
  • Publication number: 20210075338
    Abstract: A series multiplex inverter includes a power conversion unit, a phase difference selection unit, a drive signal generation unit, and a drive signal output unit. The phase difference selection unit selects, from among a plurality of phase difference candidates, the phase difference between rectangular wave voltages from a plurality of single-phase inverters. The drive signal generation unit generates a plurality of drive signals that causes the different single-phase inverters to output a plurality of rectangular wave voltages sequentially out of phase by the phase difference selected by the phase difference selection unit. The drive signal output unit outputs the plurality of drive signals generated by the drive signal generation unit to the plurality of single-phase inverters.
    Type: Application
    Filed: January 30, 2018
    Publication date: March 11, 2021
    Applicant: Mitsubishi Electric Corporation
    Inventors: Kazufumi TANAKA, Kazutoshi KURAHASHI, Yoshiaki YAMAMOTO, Shuta ISHIKAWA
  • Publication number: 20210067054
    Abstract: A series multiplex inverter includes a power conversion unit, a drive signal generation unit, and a drive signal output unit. The drive signal generation unit generates n drive signals that cause different single-phase inverters of n single-phase inverters to output n rectangular wave voltages sequentially out of phase, where n is an integer of three or more. The drive signal output unit outputs the n drive signals to the n single-phase inverters in rotation that shifts, by p every m-fold time of half an output voltage period of the power conversion unit, the single-phase inverters corresponding one-to-one to the n drive signals in a combination of the n drive signals with different single-phase inverters of the n single-phase inverters, where m is a natural number and p is a natural number relatively prime to n or one.
    Type: Application
    Filed: January 29, 2018
    Publication date: March 4, 2021
    Applicant: Mitsubishi Electric Corporation
    Inventors: Kazufumi TANAKA, Kazutoshi KURAHASHI, Yoshiaki YAMAMOTO, Shuta ISHIKAWA
  • Patent number: 10164448
    Abstract: When a plurality of storage batteries is used by connecting them in parallel, since the progress of degradation differs among the storage batteries, a power conversion system includes a degradation information acquisition device for acquiring the degradation information of the storage batteries, a temperature information acquisition device for detecting the temperature information of the storage batteries, and a control device for controlling the storage battery power converter based on the degradation information of the storage batteries by the degradation information acquisition device and the temperature information of the storage batteries by the temperature information acquisition device so that the degradation states of the plurality of the storage batteries can be matched.
    Type: Grant
    Filed: September 29, 2015
    Date of Patent: December 25, 2018
    Assignee: Mitsubishi Electric Corporation
    Inventors: Kazufumi Tanaka, Sadayuki Inoue, Makiko Kise
  • Patent number: 10116120
    Abstract: A semiconductor multilayer film mirror is configured such that a pair of an InAlN-based semiconductor film and a GaN-based semiconductor film is layered a plurality of times in a cyclic fashion and the InAlN-based semiconductor film has an In composition of less than 18 at %. The semiconductor multilayer film mirror includes a thin GaN cap layer formed on the InAlN-based semiconductor film and an AlGaN layer formed on the thin GaN cap layer between each pair of the InAlN-based semiconductor film and the GaN-based semiconductor film.
    Type: Grant
    Filed: December 8, 2017
    Date of Patent: October 30, 2018
    Assignees: STANLEY ELECTRIC CO., LTD., MEIJO UNIVERSITY
    Inventors: Tetsuya Takeuchi, Isamu Akasaki, Shinichi Tanaka, Kazufumi Tanaka
  • Publication number: 20180166856
    Abstract: A semiconductor multilayer film mirror is configured such that a pair of an InAlN-based semiconductor film and a GaN-based semiconductor film is layered a plurality of times in a cyclic fashion and the InAlN-based semiconductor film has an In composition of less than 18 at %. The semiconductor multilayer film mirror includes a thin GaN cap layer formed on the InAlN-based semiconductor film and an AlGaN layer formed on the thin GaN cap layer between each pair of the InAlN-based semiconductor film and the GaN-based semiconductor film.
    Type: Application
    Filed: December 8, 2017
    Publication date: June 14, 2018
    Applicants: MEIJO UNIVERSITY, STANLEY ELECTRIC CO., LTD.
    Inventors: Tetsuya TAKEUCHI, Isamu AKASAKI, Shinichi TANAKA, Kazufumi TANAKA
  • Publication number: 20170366023
    Abstract: When a plurality of storage batteries is used by connecting them in parallel, since the progress of degradation differs among the storage batteries, a power conversion system includes a degradation information acquisition device for acquiring the degradation information of the storage batteries; a temperature information acquisition device for detecting the temperature information of the storage batteries, and a control device for controlling the storage battery power converter based on the degradation information of the storage batteries by the degradation information acquisition device and the temperature information of the storage batteries by the temperature information acquisition device so that the degradation states of the plurality of the storage batteries can be matched.
    Type: Application
    Filed: September 29, 2015
    Publication date: December 21, 2017
    Applicant: Mitsubishi Electric Corporation
    Inventors: Kazufumi TANAKA, Sadayuki INOUE, Makiko KISE
  • Patent number: 9711255
    Abstract: There is provided an ultraviolet-emitting material that is formed so as to include Mg1?xZnxO (0<x<0.55) with a rock-salt structure or Be1?x?y?zMgyZnxCazO (0.45?y+z<1, 0<x?0.55) with a rock-salt structure.
    Type: Grant
    Filed: January 12, 2016
    Date of Patent: July 18, 2017
    Assignee: STANLEY ELECTRIC CO., LTD
    Inventors: Hiroyuki Kato, Kazufumi Tanaka, Takahiro Matsumoto
  • Patent number: 9680464
    Abstract: A semiconductor switch circuit includes a plurality of switching units connected in series between a high-voltage node and a low-voltage node, and a plurality of diodes provided in association with the plurality of switching units, respectively. Respective cathodes of the plurality of diodes are connected to the plurality of switching units, respectively, and the anode of the diode associated with the switching unit connected to the low-voltage node receives a predetermined power supply voltage. Each switching unit includes a semiconductor switching device, a gate drive circuit driving the semiconductor switching device, and a DC-DC converter receiving a DC voltage from a cathode of the associated diode and supplying drive power to the gate drive circuit.
    Type: Grant
    Filed: March 26, 2014
    Date of Patent: June 13, 2017
    Assignee: Mitsubishi Electric Corporation
    Inventors: Hiroyasu Iwabuki, Kazufumi Tanaka
  • Patent number: 9607824
    Abstract: A semiconductor device includes a support substrate, an insulating layer provided on the support substrate, and a semiconductor element provided on the insulating layer. The insulating layer has a lower insulating layer consisting of amorphous boron nitride, and an upper insulating layer provided on the lower insulating layer and including amorphous boron nitride and an hexagonal system boron nitride (h-BN) particles.
    Type: Grant
    Filed: December 3, 2015
    Date of Patent: March 28, 2017
    Assignee: STANLEY ELECTRIC CO., LTD.
    Inventor: Kazufumi Tanaka
  • Patent number: 9548664
    Abstract: A gate-power-supply device is provided with an inverter circuit, a transformer, and rectifier circuits. The device includes secondary-side parallel capacitors, connected in parallel to secondary-side coils of the transformer, for cancelling inductance components of the secondary-side coils at the drive frequency of the inverter circuit. The device includes a primary-side series capacitor, connected in series to a primary-side coil of the transformer, for cancelling the imaginary term (inductance component) of the combined impedance of the gate drivers, the rectifier circuits, the secondary-side parallel capacitors, the secondary-side coils, transformer cores and the primary-side coil, which are a load viewed from the inverter circuit.
    Type: Grant
    Filed: July 25, 2014
    Date of Patent: January 17, 2017
    Assignee: Mitsubishi Electric Corporation
    Inventors: Takuya Yabumoto, Kazufumi Tanaka, Hiroyasu Iwabuki
  • Patent number: 9490726
    Abstract: In order to obtain a contactless power supply device which, even when a spatial gap between a primary winding and a secondary winding varies, is capable of not only accurately detecting whether or not the primary winding and the secondary winding come into the position opposite to each other, but also detecting how large the spatial gap between the primary winding and the secondary winding is created, the contactless power supply device is provided with a drive voltage detection unit which detects the drive voltage of an inverter circuit, a drive current detection unit which detects the drive current of the inverter circuit, and a primary component extraction unit which, from the drive voltage and the drive current, extracts a primary drive voltage and a primary drive current including the first order frequency-components having the same frequency as a drive frequency of the inverter circuit.
    Type: Grant
    Filed: September 5, 2012
    Date of Patent: November 8, 2016
    Assignee: Mitsubishi Electric Corporation
    Inventors: Kazufumi Tanaka, Sadayuki Matsumoto
  • Publication number: 20160211046
    Abstract: There is provided an ultraviolet-emitting material that is formed so as to include Mg1?xZnxO (0<x<0.55) with a rock-salt structure or Be1?x?y?zMgyZnxCazO (0.45?y+z<1, 0<x?0.55) with a rock-salt structure.
    Type: Application
    Filed: January 12, 2016
    Publication date: July 21, 2016
    Applicant: STANLEY ELECTRIC CO., LTD.
    Inventors: Hiroyuki KATO, Kazufumi TANAKA, Takahiro MATSUMOTO
  • Publication number: 20160197604
    Abstract: A semiconductor switch circuit includes a plurality of switching units connected in series between a high-voltage node and a low-voltage node, and a plurality of diodes provided in association with the plurality of switching units, respectively. Respective cathodes of the plurality of diodes are connected to the plurality of switching units, respectively, and the anode of the diode associated with the switching unit connected to the low-voltage node receives a predetermined power supply voltage. Each switching unit includes a semiconductor switching device, a gate drive circuit driving the semiconductor switching device, and a DC-DC converter receiving a DC voltage from a cathode of the associated diode and supplying drive power to the gate drive circuit.
    Type: Application
    Filed: March 26, 2014
    Publication date: July 7, 2016
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventors: Hiroyasu IWABUKI, Kazufumi TANAKA
  • Publication number: 20160163537
    Abstract: A semiconductor device includes a support substrate, an insulating layer provided on the support substrate, and a semiconductor element provided on the insulating layer. The insulating layer has a lower insulating layer consisting of amorphous boron nitride, and an upper insulating layer provided on the lower insulating layer and including amorphous boron nitride and an hexagonal system boron nitride (h-BN) particles.
    Type: Application
    Filed: December 3, 2015
    Publication date: June 9, 2016
    Applicant: STANLEY ELECTRIC CO., LTD.
    Inventor: Kazufumi TANAKA
  • Publication number: 20160099650
    Abstract: A gate-power-supply device is provided with an inverter circuit, a transformer, and rectifier circuits. The device includes secondary-side parallel capacitors, connected in parallel to secondary-side coils of the transformer, for cancelling inductance components of the secondary-side coils at the drive frequency of the inverter circuit. The device includes a primary-side series capacitor, connected in series to a primary-side coil of the transformer, for cancelling the imaginary term (inductance component) of the combined impedance of the gate drivers, the rectifier circuits, the secondary-side parallel capacitors, the secondary-side coils, transformer cores and the primary-side coil, which are a load viewed from the inverter circuit.
    Type: Application
    Filed: July 25, 2014
    Publication date: April 7, 2016
    Applicant: Mitsubishi Electric Corporation
    Inventors: Takuya YABUMOTO, Kazufumi TANAKA, Hiroyasu IWABUKI
  • Patent number: 8796055
    Abstract: A method for manufacturing a Group III nitride semiconductor light-emitting element of the invention includes a substrate-processing process of forming a main surface including a flat surface and a convex portion 13 on the substrate 10, an epitaxial process of epitaxially growing an underlying layer on the main surface of the substrate 10 so as to cover the flat surface and the convex portion 13, and an LED lamination process of forming an LED structure by epitaxially growing a Group III nitride semiconductor. In the substrate-processing process, mask patterns 15 are sequentially formed in respective regions R1 and R2 of the flat surface using a polygonal reticle 51 having two pairs of parallel opposing ends in a plan view, by a stepper exposure method, and then the flat surface is etched to dispose and form three arbitrary convex portions 13, which are arranged to be adjacent to each other, in an isosceles triangular shape in a plan view.
    Type: Grant
    Filed: February 21, 2013
    Date of Patent: August 5, 2014
    Assignee: Toyoda Gosei Co., Ltd.
    Inventor: Kazufumi Tanaka
  • Publication number: 20140198544
    Abstract: In order to obtain a contactless power supply device which, even when a spatial gap between a primary winding and a secondary winding varies, is capable of not only accurately detecting whether or not the primary winding and the secondary winding come into the position opposite to each other, but also detecting how large the spatial gap between the primary winding and the secondary winding is created, the contactless power supply device is provided with a drive voltage detection unit which detects the drive voltage of an inverter circuit, a drive current detection unit which detects the drive current of the inverter circuit, and a primary component extraction unit which, from the drive voltage and the drive current, extracts a primary drive voltage and a primary drive current including the first order frequency-components having the same frequency as a drive frequency of the inverter circuit.
    Type: Application
    Filed: September 5, 2012
    Publication date: July 17, 2014
    Applicant: Mitsubishi Electric Corporation
    Inventors: Kazufumi Tanaka, Sadayuki Matsumoto