Patents by Inventor Tatsuya Okuda
Tatsuya Okuda 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).
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Publication number: 20240136881Abstract: A metal support structural body is provided on the radially outer side of a phase ring for connecting a rotating electric machine armature winding at a stator end. An insulator ensuring an insulation distance to the ground is interposed between the phase ring and the metal support structural body. Thus, long-term reliability improves as compared to a conventional insulation-to-ground structure. Since the insulation distance to the ground is ensured by the insulator, the phase ring and the metal support structural body are configured with an insulation thickness smaller than needed for insulation to the ground, thereby improving cooling performance for the phase ring and the metal support structural body. Occurrence of induced current in the metal support structural body is suppressed, thus allowing application of a simple fastening structure such as metal bolts to a stator frame.Type: ApplicationFiled: May 13, 2021Publication date: April 25, 2024Applicant: Mitsubishi Electric CorporationInventors: Wataru YAMASHITA, Tatsuya OKUDA
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Patent number: 11965469Abstract: In an internal combustion engine having a cylinder in which an air-fuel mixture of gaseous fuel and intake air is combusted, an intake passage connected to the cylinder, and a supercharger for supercharging the intake air, in a case where backfire is generated in a set period before supercharging is performed by the supercharger, supercharging is performed at a smaller supercharging pressure than in a case where backfire is not generated in the set period.Type: GrantFiled: August 17, 2023Date of Patent: April 23, 2024Assignee: Toyota Jidosha Kabushiki KaishaInventors: Toshiaki Tamachi, Yoshito Sekiguchi, Masato Nakano, Koichi Okuda, Tatsuya Imamura, Atsushi Tabata
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Publication number: 20240118655Abstract: An object of the present disclosure is to provide an electrophotographic photosensitive member with suppressed positive ghosts, and a process cartridge and an electrophotographic apparatus each including the electrophotographic photosensitive member. The present disclosure provides an electrophotographic photosensitive member having a support and a photosensitive layer on the support; the photosensitive layer comprises (?) a compound represented by the formula (1), and (?) at least one selected from the group consisting of a compound represented by the formula (2) and a compound represented by the formula (3), wherein a content of the (?) with respect to a content of the (?) is 50 to 850 mass ppm in the photosensitive layer.Type: ApplicationFiled: September 8, 2023Publication date: April 11, 2024Inventors: KUNIHIKO SEKIDO, SHUHEI IWASAKI, TATSUYA OHSAWA, NAOYUKI MATSUMOTO, ATSUSHI OKUDA, TSUTOMU NISHIDA
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Publication number: 20240068420Abstract: In an internal combustion engine having a cylinder in which an air-fuel mixture of gaseous fuel and intake air is combusted, an intake passage connected to the cylinder, and a supercharger for supercharging the intake air, in a case where backfire is generated in a set period before supercharging is performed by the supercharger, supercharging is performed at a smaller supercharging pressure than in a case where backfire is not generated in the set period.Type: ApplicationFiled: August 17, 2023Publication date: February 29, 2024Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHAInventors: Toshiaki TAMACHI, Yoshito SEKIGUCHI, Masato NAKANO, Koichi OKUDA, Tatsuya IMAMURA, Atsushi TABATA
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Patent number: 11791712Abstract: A power conversion device converts a direct-current power on the DC side of the power conversion device to an alternating-current power by an inverter circuit having a plurality of semiconductor switching elements, and outputs the AC power from the AC side of the power conversion device. A current detector detects a reactor current output from the inverter circuit. As overcurrent detector detects overcurrent in a control mode in which the reactor current is caused to follow a reactor current command value, control circuit starts an overcurrent mode in which a time period where the reactor current monotonically decreases is provided. In the overcurrent mode, whether to switch the overcurrent mode to the normal control mode is determined based on the reactor current or in accordance with a timing corresponding to a zero-cross point of a voltage or current on the AC side.Type: GrantFiled: January 9, 2019Date of Patent: October 17, 2023Assignee: MITSUBISHI ELECTRIC CORPORATIONInventors: Takeshi Amimoto, Kikuo Izumi, Tatsuya Okuda, Tomoaki Kimura
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Publication number: 20220209588Abstract: Stacked core sheets forming a stacked core of a rotating electric machine have tooth portions on the inner circumferential side. Axial-direction holes penetrating the stacked core in the axial direction are provided near the tooth bases and near the outer circumferential surface. Resin is injected through tooth base neighbor holes near the tooth bases and core outer circumferential holes near the outer circumferential surface of the stacked core, among the axial-direction holes in the rotating electric machine. Thus, the resin fills gaps near the tooth bases and near the outer circumferential surface of the stacked core, so that the stacked core sheets are bonded to each other, thus obtaining a rotating electric machine having such a stacked core.Type: ApplicationFiled: May 14, 2019Publication date: June 30, 2022Applicant: Mitsubishi Electric CorporationInventors: Tatsuya OKUDA, Minoru AOKI
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Patent number: 11349409Abstract: A control circuit corrects a reference gain by multiplying the reference gain by a correction value set in association with state-of-charge information of a storage battery, and uses the corrected reference gain as a first gain for controlling a DC/AC inverter, to adjust the slope of frequency drooping characteristic. The correction value is a value that gradually decreases with increase in state-of-charge information of the storage battery, the minimum value of the correction value is N1 which is a real number greater than 0 and corresponding to a first state of charge for stopping charging of the storage battery, and the maximum value of the correction value is N2 which is a real number greater than N1 and corresponding to a second state of charge for stopping discharging of the storage battery.Type: GrantFiled: March 18, 2019Date of Patent: May 31, 2022Assignee: MITSUBISHI ELECTRIC CORPORATIONInventors: Kenji Fujiwara, Tatsuya Okuda, Takahiro Kato
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Publication number: 20210367531Abstract: A control circuit corrects a reference gain by multiplying the reference gain by a correction value set in association with state-of-charge information of a storage battery, and uses the corrected reference gain as a first gain for controlling a DC/AC inverter, to adjust the slope of frequency drooping characteristic. The correction value is a value that gradually decreases with increase in state-of-charge information of the storage battery, the minimum value of the correction value is N1 which is a real number greater than 0 and corresponding to a first state of charge for stopping charging of the storage battery, and the maximum value of the correction value is N2 which is a real number greater than N1 and corresponding to a second state of charge for stopping discharging of the storage battery.Type: ApplicationFiled: March 18, 2019Publication date: November 25, 2021Applicant: Mitsubishi Electric CorporationInventors: Kenji FUJIWARA, Tatsuya OKUDA, Takahiro KATO
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Patent number: 10992240Abstract: A power conversion device which reduces switching losses and stabilizes the output power. A switching-mode changer generates a reference signal for switching a mode of operation of the full-bridge circuit to a first switching mode or a second switching mode. In the first switching mode, an upper arm and a lower arm are switched synchronously, and a lower arm and an upper arm are non-conducting. In the second switching mode, the lower arm and the upper arm are switched synchronously, and the upper arm and the lower arm are non-conducting. The switching-mode changer adjusts the phase of the reference signal so that the reactive power is reduced.Type: GrantFiled: September 20, 2018Date of Patent: April 27, 2021Assignees: Mitsubishi Electric Corporation, National University Corporation Nagaoka University of TechnologyInventors: Yu Kawai, Tatsuya Okuda, Jun-ichi Itoh, Hoai Nam Le
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Publication number: 20210013796Abstract: A power conversion device converts a direct-current power on the DC side of the power conversion device to an alternating-current power by an inverter circuit having a plurality of semiconductor switching elements, and outputs the AC power from the AC side of the power conversion device. A current detector detects a reactor current output from the inverter circuit. As overcurrent detector detects overcurrent in a control mode in which the reactor current is caused to follow a reactor current command value, control circuit starts an overcurrent mode in which a time period where the reactor current monotonically decreases is provided. In the overcurrent mode, whether to switch the overcurrent mode to the normal control mode is determined based on the reactor current or in accordance with a timing corresponding to a zero-cross point of a voltage or current on the AC side.Type: ApplicationFiled: January 9, 2019Publication date: January 14, 2021Applicant: Mitsubishi Electric CorporationInventors: Takeshi AMIMOTO, Kikuo IZUMI, Tatsuya OKUDA, Tomoaki KIMURA
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Patent number: 10855084Abstract: A power system and a power conversion device are interconnected via an interconnection switch. A user load is provided between the power conversion device and the interconnection switch. In parallel with the interconnection switch, a series circuit composed of a load disconnection switch and a voltage maintenance load for maintaining voltage of the user load at the time of system momentary power interruption is connected. Control is performed such that, when momentary power interruption occurs, the interconnection switch is turned off and the power system and the power conversion device are connected via the voltage maintenance load, and at the time of recovery from the momentary power interruption, the interconnection switch is turned on, further the power system and the power conversion device are connected.Type: GrantFiled: May 12, 2017Date of Patent: December 1, 2020Assignee: MITSUBISHI ELECTRIC CORPORATIONInventors: Kikuo Izumi, Tatsuya Okuda, Masahiro Sugahara
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Publication number: 20200295674Abstract: A power conversion device which reduces switching losses and stabilizes the output power. A switching-mode changer generates a reference signal for switching a mode of operation of the full-bridge circuit to a first switching mode or a second switching mode. In the first switching mode, an upper arm and a lower arm are switched synchronously, and a lower arm and an upper arm are non-conducting. In the second switching mode, the lower arm and the upper arm are switched synchronously, and the upper arm and the lower arm are non-conducting. The switching-mode changer adjusts the phase of the reference signal so that the reactive power is reduced.Type: ApplicationFiled: September 20, 2018Publication date: September 17, 2020Applicants: Mitsubishi Electric Corporation, National University Corporation Nagaoka University of TechnologyInventors: Yu KAWAI, Tatsuya OKUDA, Jun-ichi ITOH, Hoai Nam LE
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Publication number: 20200059103Abstract: A power system and a power conversion device are interconnected via an interconnection switch. A user load is provided between the power conversion device and the interconnection switch. In parallel with the interconnection switch, a series circuit composed of a load disconnection switch and a voltage maintenance load for maintaining voltage of the user load at the time of system momentary power interruption is connected. Control is performed such that, when momentary power interruption occurs, the interconnection switch is turned off and the power system and the power conversion device are connected via the voltage maintenance load, and at the time of recovery from the momentary power interruption, the interconnection switch is turned on, further the power system and the power conversion device are connected.Type: ApplicationFiled: May 12, 2017Publication date: February 20, 2020Applicant: Mitsubishi Electric CorporationInventors: Kikuo IZUMI, Tatsuya OKUDA, Masahiro SUGAHARA
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Patent number: 10256747Abstract: In a control unit for drive-controlling a switching element unit of each power conversion device, a voltage correction amount calculation unit calculates a correction amount corresponding to voltage drop due to impedance between the switching element unit and filter reactor. A voltage command correcting unit corrects a voltage command generated by the voltage command generation unit, using the correction amount. Thus, for a power conversion device 21 that has a small output impedance, correction is performed so as to increase the output impedance, and a PLL unit changes the frequency in accordance with active power calculated from output voltage and output current of the power conversion device, so as to uniform power allocations.Type: GrantFiled: November 16, 2016Date of Patent: April 9, 2019Assignee: Mitsubishi Electric CorporationInventors: Takahiro Kato, Yu Kawai, Kenji Fujiwara, Kikuo Izumi, Tatsuya Okuda
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Publication number: 20180358907Abstract: In a control unit for drive-controlling a switching element unit of each power conversion device, a voltage correction amount calculation unit calculates a correction amount corresponding to voltage drop due to impedance between the switching element unit and filter reactor. A voltage command correcting unit corrects a voltage command generated by the voltage command generation unit, using the correction amount. Thus, for a power conversion device 21 that has a small output impedance, correction is performed so as to increase the output impedance, and a PLL unit changes the frequency in accordance with active power calculated from output voltage and output current of the power conversion device, so as to uniform power allocations.Type: ApplicationFiled: November 16, 2016Publication date: December 13, 2018Applicant: Mitsubishi Electric CorporationInventors: Takahiro KATO, Yu KAWAI, Kenji FUJIWARA, Kikuo IZUMI, Tatsuya OKUDA
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Patent number: 10084315Abstract: A power conversion circuit for converting DC power supplied from a DC power supply to AC power; and a power conversion control section for controlling operation of the power conversion circuit so as to generate autonomous operation power as an AC voltage source in a parallel-off state from a power grid. The power conversion control section includes: an AC voltage control section for controlling AC voltage; an AC current suppression section for limiting AC current to a predetermined current limit value or smaller; and a DC voltage shortage suppression section for, when DC voltage of the power conversion circuit reduces, in response thereto, reducing the current limit value to be given to the AC current suppression section.Type: GrantFiled: July 4, 2014Date of Patent: September 25, 2018Assignee: Mitsubishi Electric CorporationInventors: Tatsuya Okuda, Kikuo Izumi, Takahiro Kato
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Patent number: 10044282Abstract: Using two converters placed in a primary-side and a secondary-side and each configured as a single-phase full-bridge, and one single-phase transformer TR, a power conversion device converts DC power of a primary-side capacitor to which a primary-side DC voltage is applied, to DC power of a secondary-side capacitor to which a secondary-side DC voltage is applied, through a transformer. A control device sets a dead time Td1 for the converter serving as a power-transferring side converter, to be equal to or less than a current-polarity reversal time Tcmtt, to thereby surely achieve zero-voltage switching.Type: GrantFiled: February 24, 2016Date of Patent: August 7, 2018Assignee: Mitsubishi Electric CorporationInventors: Takushi Jimichi, Tatsuya Okuda, Osamu Mori, Takaharu Ishibashi
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Patent number: 9912150Abstract: In a power control system which connects power from the power storage device to a power grid and supplies power to a load, the power from the power storage device is connected to the load and the power grid via a DC/DC converter, a smoothing capacitor, and a DC/AC converter. By a first power control unit for controlling flow power of the power grid to be a power command value, and by a second power control unit for suppressing reverse flow power, an output power command for the DC/AC converter is generated, an output power command for the DC/DC converter is generated so that voltage of the smoothing capacitor becomes target voltage, and the output power command is corrected so as to suppress voltage variation in the smoothing capacitor.Type: GrantFiled: May 21, 2014Date of Patent: March 6, 2018Assignee: Mitsubishi Electric CorporationInventors: Kikuo Izumi, Tatsuya Okuda, Tsutomu Shimazaki, Naohide Tsuchimoto
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Publication number: 20180054136Abstract: Using two converters placed in a primary-side and a secondary-side and each configured as a single-phase full-bridge, and one single-phase transformer TR, a power conversion device converts DC power of a primary-side capacitor to which a primary-side DC voltage is applied, to DC power of a secondary-side capacitor to which a secondary-side DC voltage is applied, through a transformer. A control device sets a dead time Td1 for the converter serving as a power-transferring side converter, to be equal to or less than a current-polarity reversal time Tcmtt, to thereby surely achieve zero-voltage switching.Type: ApplicationFiled: February 24, 2016Publication date: February 22, 2018Applicant: Mitsubishi Electric CorporationInventors: Takushi JIMICHI, Tatsuya OKUDA, Osamu MORI, Takaharu ISHIBASHI
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Publication number: 20160204691Abstract: A power conversion circuit for converting DC power supplied from a DC power supply to AC power; and a power conversion control section for controlling operation of the power conversion circuit so as to generate autonomous operation power as an AC voltage source in a parallel-off state from a power grid. The power conversion control section includes: an AC voltage control section for controlling AC voltage; an AC current suppression section for limiting AC current to a predetermined current limit value or smaller; and a DC voltage shortage suppression section for, when DC voltage of the power conversion circuit reduces, in response thereto, reducing the current limit value to be given to the AC current suppression section.Type: ApplicationFiled: July 4, 2014Publication date: July 14, 2016Applicant: Mitsubishi Electric CorporationInventors: Tatsuya OKUDA, Kikuo IZUMI, Takahiro KATO