Patents by Inventor Keiji Tashiro

Keiji Tashiro 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: 20220037074
    Abstract: A power conversion device includes a multilayer board including conductive layers that form a primary-side coil and a secondary-side coil of a transformer; and a circuit board electrically connected to the multilayer board, having a first conversion circuit formed therein or thereon. The multilayer board includes a transformer region in which the transformer is formed; a core member disposed in the transformer region and around the primary-side coil and secondary-side coil are wound; a circuit formed region which is adjacent to the transformer region and a second conversion circuit is formed, the second conversion circuit being electrically connected to the primary-side coil or the secondary-side coil; and a terminal portion which is electrically connected to the secondary-side coil or the primary-side coil. The first conversion circuit is electrically connected to the transformer via the terminal portion. One of the coils has a smaller number of turns than the other coil.
    Type: Application
    Filed: October 11, 2019
    Publication date: February 3, 2022
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventor: Keiji TASHIRO
  • Publication number: 20210344268
    Abstract: A semiconductor switch driving apparatus is configured to drive a semiconductor switch, the semiconductor switch not having a body diode and having a threshold voltage for performing switching between off and on lower than a threshold voltage of a silicon device. The semiconductor switch driving apparatus includes: a first drive voltage switching circuit configured to switch a drive voltage of the semiconductor switch to a first adjustment voltage between an off-voltage and an on-voltage, at a predetermined time immediately before a timing at which the semiconductor switch is driven from off to on; and a second drive voltage switching circuit configured to switch, after the drive voltage of the semiconductor switch has been switched by the first drive voltage switching circuit, the drive voltage of the semiconductor switch to the on-voltage at the timing at which the semiconductor switch is driven from off to on.
    Type: Application
    Filed: July 24, 2019
    Publication date: November 4, 2021
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Masayoshi HIROTA, Keiji TASHIRO
  • Patent number: 10811953
    Abstract: A power supply device comprises: a first switching circuit that includes a series circuit, connected between a predetermined voltage level and a ground level, having a high side switching element and a low side switching element connected in series that are alternately turned on and off at a predetermined frequency; a second switching circuit that includes a switching element controlled between on and off, the switching element having one end being connected to the ground level, and that makes an ON time point of the switching element variable; and a control unit that performs control such that ON time points of the switching element and the high side switching element are not overlapped with each other.
    Type: Grant
    Filed: September 21, 2016
    Date of Patent: October 20, 2020
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Masayoshi Hirota, Keiji Tashiro
  • Patent number: 10523113
    Abstract: A power conversion apparatus comprises a bidirectional conversion circuit that enables first conversion converting DC to AC and second conversion converting AC to DC and a filter circuit that is provided on an AC side of the bidirectional conversion circuit and that includes a capacitor. A control unit is provided for performing control such that the bidirectional conversion circuit makes the first conversion during the former stage of each half cycle of AC voltage, and such that the bidirectional conversion circuit makes the second conversion during the latter stage of each half cycle of AC voltage. The control unit performs control such that AC current of an opposite polarity to that of the AC voltage flows to the AC side during the former stage and AC current of the same polarity as that of the AC voltage flows to the AC side during the latter stage.
    Type: Grant
    Filed: December 23, 2016
    Date of Patent: December 31, 2019
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Takaaki Sano, Takeshi Ariyoshi, Keiji Tashiro
  • Patent number: 10483851
    Abstract: Provided is a voltage conversion device including: a voltage conversion circuit having two inductors that are wound around a core and that magnetically cancel each other out, and switching elements that switch current flowing through the respective inductors; and a control unit that alternately turns on and off each of the switching elements. The coupling coefficient of the two inductors is in the range from ?0.99 to ?0.78.
    Type: Grant
    Filed: May 29, 2017
    Date of Patent: November 19, 2019
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Keiji Tashiro, Xiaoguang Zheng
  • Publication number: 20190149049
    Abstract: Provided is a voltage conversion device including: a voltage conversion circuit having two inductors that are wound around a core and that magnetically cancel each other out, and switching elements that switch current flowing through the respective inductors; and a control unit that alternately turns on and off each of the switching elements. The coupling coefficient of the two inductors is in the range from ?0.99 to ?0.78.
    Type: Application
    Filed: May 29, 2017
    Publication date: May 16, 2019
    Inventors: Keiji Tashiro, Xiaoguang Zheng
  • Patent number: 10291115
    Abstract: A power factor correcting device that controls switching of a converter that converts AC voltage inputted via a circuit with a capacitor through which reactive current flows into DC voltage calculates the magnitude of the reactive current based on the magnitude of the AC voltage inputted to the converter and the capacitance of the capacitor and corrects a power factor including the circuit, calculates a target value for a phase delay of the AC current with respect to the AC voltage based on the calculated magnitude and the magnitude of the AC current inputted to the converter or the magnitude of the DC power outputted from the converter, and calculates an operation amount for delaying the phase of the switching based on the calculated target value.
    Type: Grant
    Filed: November 4, 2016
    Date of Patent: May 14, 2019
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Takaaki Sano, Takeshi Ariyoshi, Keiji Tashiro
  • Patent number: 10250121
    Abstract: A converter comprises: a preceding converter having a first switching circuit intermittently outputting current; a capacitor smoothing the current output from the first switching circuit; and a succeeding converter having a second switching circuit to which the current smoothed by the capacitor is intermittently input. The converter converts direct current or alternating current input to the preceding converter and outputs the converted direct current or alternating current from the succeeding converter. A control circuit controls switching of the first and second switching circuits so that an end time point of an output period during which current is output from the first switching circuit has a time difference with a start time point of an input period during which current is input to the second switching circuit.
    Type: Grant
    Filed: February 9, 2016
    Date of Patent: April 2, 2019
    Assignees: Sumitomo Electric Industries, Ltd., Sumitomo Wiring Systems, Ltd., Autonetworks Technologies, Ltd.
    Inventors: Masayoshi Hirota, Tatsuya Izumi, Keiji Tashiro
  • Patent number: 10224818
    Abstract: Provided are a control unit having a first control state in which a first switching element and a second switching element of one series circuit are turned on and a second control state to which the first control state shifts and in which a first switching element of another series circuit and the second switching element of the one series circuit are turned on, and executing control so as to apply predetermined voltage to the other side of a transformer during a predetermined time period during the first control state before shifting to the second control state.
    Type: Grant
    Filed: May 27, 2016
    Date of Patent: March 5, 2019
    Assignees: Sumitomo Electric Industries, Ltd., Sumitomo Wiring Systems, Ltd., AutoNetworks Technologies, Ltd.
    Inventors: Masayoshi Hirota, Keiji Tashiro
  • Publication number: 20180323701
    Abstract: A power conversion apparatus comprises a bidirectional conversion circuit that enables first conversion converting DC to AC and second conversion converting AC to DC and a filter circuit that is provided on an AC side of the bidirectional conversion circuit and that includes a capacitor. A control unit is provided for performing control such that the bidirectional conversion circuit makes the first conversion during the former stage of each half cycle of AC voltage, and performing control such that the bidirectional conversion circuit makes the second conversion during the latter stage of each half cycle of AC voltage. The control unit performs control such that AC current of an opposite polarity to that of the AC voltage flows to an AC side of the bidirectional conversion circuit during the former stage and performs control such that AC current of the same polarity as that of the AC voltage flows to the AC side of the bidirectional conversion circuit during the latter stage.
    Type: Application
    Filed: December 23, 2016
    Publication date: November 8, 2018
    Inventors: Takaaki Sano, Takeshi Ariyoshi, Keiji Tashiro
  • Publication number: 20180278149
    Abstract: A power factor correcting device that controls switching of a converter that converts AC voltage inputted via a circuit with a capacitor through which reactive current flows into DC voltage calculates the magnitude of the reactive current based on the magnitude of the AC voltage inputted to the converter and the capacitance of the capacitor and corrects a power factor including the circuit, calculates a target value for a phase delay of the AC current with respect to the AC voltage based on the calculated magnitude and the magnitude of the AC current inputted to the converter or the magnitude of the DC power outputted from the converter, and calculates an operation amount for delaying the phase of the switching based on the calculated target value.
    Type: Application
    Filed: November 4, 2016
    Publication date: September 27, 2018
    Inventors: Takaaki Sano, Takeshi Ariyoshi, Keiji Tashiro
  • Publication number: 20180219471
    Abstract: A power supply device comprises: a first switching circuit that includes a series circuit, connected between a predetermined voltage level and a ground level, having a high side switching element and a low side switching element connected in series that are alternately turned on and off at a predetermined frequency; a second switching circuit that includes a switching element controlled between on and off, the switching element having one end being connected to the ground level, and that makes an ON time point of the switching element variable; and a control unit that performs control such that ON time points of the switching element and the high side switching element are not overlapped with each other.
    Type: Application
    Filed: September 21, 2016
    Publication date: August 2, 2018
    Inventors: Masayoshi Hirota, Keiji Tashiro
  • Publication number: 20180109193
    Abstract: Provided are a control unit having a first control state in which a first switching element and a second switching element of one series circuit are turned on and a second control state to which the first control state shifts and in which a first switching element of another series circuit and the second switching element of the one series circuit are turned on, and executing control so as to apply predetermined voltage to the other side of a transformer during a predetermined time period during the first control state before shifting to the second control state.
    Type: Application
    Filed: May 27, 2016
    Publication date: April 19, 2018
    Inventors: Masayoshi Hirota, Keiji Tashiro
  • Publication number: 20180026520
    Abstract: A converter comprises: a preceding converter having a first switching circuit intermittently outputting current; a capacitor smoothing the current output from the first switching circuit; and a succeeding converter having a second switching circuit to which the current smoothed by the capacitor is intermittently input. The converter converts direct current or alternating current input to the preceding converter and outputs the converted direct current or alternating current from the succeeding converter. A control circuit controls switching of the first and second switching circuits so that an end time point of an output period during which current is output from the first switching circuit has a time difference with a start time point of an input period during which current is input to the second switching circuit.
    Type: Application
    Filed: February 9, 2016
    Publication date: January 25, 2018
    Inventors: Masayoshi Hirota, Tatsuya Izumi, Keiji Tashiro
  • Patent number: 9787090
    Abstract: A mixer (power packet generation device) 2 includes switches 21A, 21B, packet generation means 28A, 28B, and a selector 29. The packet generator 28A (28B) causes the switch 21A (21B) to perform ON/OFF operation, based on a target voltage, and a voltage estimated as being applied to a load 4A (4B) in each of a state where a power packet is supplied to the load and a state where no power packet is supplied to the load. The selector 29 performs switching between a state where the packet generators 28A, 28B cause the switches 21A, 21B to perform ON/OFF operation, and a state where the packet generators 28A, 28B maintain the switches 21A, 21B in their OFF states.
    Type: Grant
    Filed: May 20, 2014
    Date of Patent: October 10, 2017
    Assignee: Kyoto University
    Inventors: Takashi Hikihara, Shun-ichi Azuma, Ryo Takahashi, Keiji Tashiro
  • Publication number: 20160094029
    Abstract: A mixer (power packet generation device) 2 includes switches 21A, 21B, packet generation means 28A, 28B, and a selector 29. The packet generator 28A (28B) causes the switch 21A (21B) to perform ON/OFF operation, based on a target voltage, and a voltage estimated as being applied to a load 4A (4B) in each of a state where a power packet is supplied to the load and a state where no power packet is supplied to the load. The selector 29 performs switching between a state where the packet generators 28A, 28B cause the switches 21A, 21B to perform ON/OFF operation, and a state where the packet generators 28A, 28B maintain the switches 21A, 21B in their OFF states.
    Type: Application
    Filed: May 20, 2014
    Publication date: March 31, 2016
    Inventors: Takashi HIKIHARA, Shun-ichi AZUMA, Ryo TAKAHASHI, Keiji TASHIRO
  • Publication number: 20030004233
    Abstract: A resin composition comprises a matrix resin and short cellulosic fibers dyed with at least one threne dye. A molded product, which has a nonwoven-fabric-like external appearance at a surface thereof, is obtained by molding a molding resin composition which comprises one of the resin compositions and an uncolored resin.
    Type: Application
    Filed: February 8, 2002
    Publication date: January 2, 2003
    Applicant: Dainichiseika Color & Chem. Mfg. Co., Ltd.
    Inventors: Isamu Yamaguchi, Keiji Tashiro, Toshihiro Yamada, Junseki Kanehara