Patents by Inventor Masaki Hirakata
Masaki Hirakata 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: 20240118637Abstract: An electrophotographic photoreceptor includes a conductive substrate, an undercoat layer provided on the conductive substrate, a charge generation layer provided on the undercoat layer, a charge transport layer provided on the charge generation layer, and a surface protective layer provided on the charge transport layer, in which a dark decay is 85 V/sec or greater in a case where the electrophotographic photoreceptor is contact-charged with a DC voltage.Type: ApplicationFiled: August 7, 2023Publication date: April 11, 2024Applicant: FUJIFILM Business Innovation Corp.Inventors: Satoshi MIZOGUCHI, Takeshi KAWAI, Masaki HIRAKATA, Yuki YONETOKU, Hideya KATSUHARA
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Patent number: 11894791Abstract: A control device includes a control circuit configured to control an inverter circuit that drives a motor by a plurality of switching elements coupled between DC buses, a first power supply system using a voltage source different from the DC buses as a power supply, a second power supply system using the DC buses as a power supply, and a switching circuit configured to switch a power supply system that supplies power to the control circuit from the first power supply system to the second power supply system when an abnormality in the first power supply system is detected. The control circuit continues control of the inverter circuit with a power consumption lower than that before the abnormality is detected in the first power supply system, when the abnormality is detected.Type: GrantFiled: May 25, 2022Date of Patent: February 6, 2024Assignee: FUJI ELECTRIC CO., LTD.Inventor: Masaki Hirakata
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Publication number: 20230412089Abstract: An object of the present invention is to provide a power converter capable of reducing inductance and preventing a manufacturing process from becoming complicated.Type: ApplicationFiled: April 26, 2023Publication date: December 21, 2023Applicant: FUJI ELECTRIC CO., LTD.Inventor: Masaki HIRAKATA
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Publication number: 20230353076Abstract: A motor drive device is provided which includes: a first drive unit configured to drive a plurality of first motor phases; a second drive unit configured to drive a plurality of second motor phases; a common sensor configured to detect a total current flowing through a phase pair obtained by selecting one phase from the plurality of first motor phases and one phase from the plurality of second motor phases; at least one first motor phase sensor and at least one second motor phase sensor configured to detect each current flowing through each phase not included in the phase pair among the plurality of first motor phases and the plurality of second motor phases, respectively; and a drive control unit configured to control drive amounts of the first drive unit and the second drive unit for the plurality of first motor phases and the plurality of second motor phases.Type: ApplicationFiled: January 23, 2023Publication date: November 2, 2023Inventor: Masaki HIRAKATA
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Publication number: 20230305408Abstract: A base material for an electrophotographic photoreceptor, in which in a spectrum of a period and an amplitude obtained by performing fast Fourier transform of surface roughness of a 10 mm portion in an axial direction of a surface of the base material for an electrophotographic photoreceptor, an amplitude in a range of a period of 0.4 mm or more and 0.7 mm or less is 0.22 mm or less.Type: ApplicationFiled: March 2, 2023Publication date: September 28, 2023Applicant: FUJIFILM Business Innovation Corp.Inventors: Masaki HIRAKATA, Kenta IDE
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Publication number: 20230020544Abstract: A control device includes a control circuit configured to control an inverter circuit that drives a motor by a plurality of switching elements coupled between DC buses, a first power supply system using a voltage source different from the DC buses as a power supply, a second power supply system using the DC buses as a power supply, and a switching circuit configured to switch a power supply system that supplies power to the control circuit from the first power supply system to the second power supply system when an abnormality in the first power supply system is detected. The control circuit continues control of the inverter circuit with a power consumption lower than that before the abnormality is detected in the first power supply system, when the abnormality is detected.Type: ApplicationFiled: May 25, 2022Publication date: January 19, 2023Inventor: Masaki HIRAKATA
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Patent number: 11394332Abstract: Provided is a motor driving apparatus including: an upper-arm gate driving circuit; a lower-arm gate driving circuit; a first rotation detection unit powered by a first power source; a second rotation detection unit powered by a second power source; a first fail safe circuit that performs, by use of a detection signal from the first rotation detection unit, a fail safe control on a gate driving circuit powered at least by the first power source, from among the upper-arm gate driving circuit and the lower-arm gate driving circuit; and a second fail safe circuit that performs, by use of a detection signal from the second rotation detection unit, a fail safe control on a gate driving circuit powered at least by the second power source, from among the upper-arm gate driving circuit and the lower-arm gate driving circuit.Type: GrantFiled: August 24, 2020Date of Patent: July 19, 2022Assignee: FUJI ELECTRIC CO., LTD.Inventor: Masaki Hirakata
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Patent number: 11356049Abstract: Provided is a motor drive device comprising a motor control unit that controls a plurality of upper arm-side switching elements and a plurality of lower arm-side switching elements provided to an inverter for driving a motor; a current determination unit that determines whether a motor current flowing through at least one switching element of the plurality of upper arm-side switching elements and the plurality of lower arm-side switching elements is equal to or smaller than a threshold value; and a short-circuit control unit that performs switching between all-on of the plurality of upper arm-side switching elements and all-on of the plurality of lower arm-side switching elements, on condition that the motor current is equal to or smaller than the threshold value, in a short-circuiting operation of alternately switching all-on of the plurality of upper arm-side switching elements and all-on of the plurality of lower arm-side switching elements.Type: GrantFiled: February 24, 2021Date of Patent: June 7, 2022Assignee: FUJI ELECTRIC CO., LTD.Inventor: Masaki Hirakata
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Publication number: 20210313922Abstract: Provided is a motor drive device comprising a motor control unit that controls a plurality of upper arm-side switching elements and a plurality of lower arm-side switching elements provided to an inverter for driving a motor; a current determination unit that determines whether a motor current flowing through at least one switching element of the plurality of upper arm-side switching elements and the plurality of lower arm-side switching elements is equal to or smaller than a threshold value; and a short-circuit control unit that performs switching between all-on of the plurality of upper arm-side switching elements and all-on of the plurality of lower arm-side switching elements, on condition that the motor current is equal to or smaller than the threshold value, in a short-circuiting operation of alternately switching all-on of the plurality of upper arm-side switching elements and all-on of the plurality of lower arm-side switching elements.Type: ApplicationFiled: February 24, 2021Publication date: October 7, 2021Inventor: Masaki HIRAKATA
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Patent number: 11012021Abstract: An inverter device includes gate driving circuits for upper and lower arms of a bridge circuit, a first power supply supplying a power supply voltage to each driving circuit, and a second power supply having a reference potential different from that of the first power supply. The inverter device also includes a first fail-safe circuit having a reference potential common to the first power supply and generating driving commands with respect to the upper and lower arms, and a second fail-safe circuit having a reference potential common to the second power supply and generating driving commands with respect to the upper or lower arm. The lower arm gate driving circuit has two driving command input functions having different reference potentials, one function inputs the driving commands from the first fail-safe circuit, and the other function inputs the driving commands from the second fail-safe circuit.Type: GrantFiled: February 21, 2020Date of Patent: May 18, 2021Assignee: FUJI ELECTRIC CO., LTD.Inventor: Masaki Hirakata
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Patent number: 10998808Abstract: A power conversion device, that includes a drive circuit 11a that drives a switching element 4 included in an upper-arm for one of three phases, a drive circuit 11b that drives a switching element 5 included in a lower-arm for the one phase, and a control circuit 9 that transmits a control signal to the drive circuits 11a, 11b, is provided. The power conversion device includes power supply circuits 12a, 12b that provide power to the drive circuits 11a, 11b, respectively, a low-voltage power supply 6 that supplies power to one of the power supply circuits, 12a, and a high-voltage power supply 1 that supplies power to the other of the power supply circuits, 12b. Accordingly, it is possible to reliably protect a system: by realizing minimal redundancy of the power supply, the power supply generation circuit, etc.; and by realizing the short-circuit mode at the time of error occurrence.Type: GrantFiled: July 23, 2018Date of Patent: May 4, 2021Assignee: FUJI ELECTRIC CO., LTD.Inventors: Masaki Hirakata, Akihiro Odaka
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Publication number: 20210111656Abstract: Provided is a motor driving apparatus including: an upper-arm gate driving circuit; a lower-arm gate driving circuit; a first rotation detection unit powered by a first power source; a second rotation detection unit powered by a second power source; a first fail safe circuit that performs, by use of a detection signal from the first rotation detection unit, a fail safe control on a gate driving circuit powered at least by the first power source, from among the upper-arm gate driving circuit and the lower-arm gate driving circuit; and a second fail safe circuit that performs, by use of a detection signal from the second rotation detection unit, a fail safe control on a gate driving circuit powered at least by the second power source, from among the upper-arm gate driving circuit and the lower-arm gate driving circuit.Type: ApplicationFiled: August 24, 2020Publication date: April 15, 2021Inventor: Masaki HIRAKATA
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Publication number: 20200195186Abstract: An inverter device includes gate driving circuits for upper and lower arms of a bridge circuit, a first power supply supplying a power supply voltage to each driving circuit, and a second power supply having a reference potential different from that of the first power supply. The inverter device also includes a first fail-safe circuit having a reference potential common to the first power supply and generating driving commands with respect to the upper and lower arms, and a second fail-safe circuit having a reference potential common to the second power supply and generating driving commands with respect to the upper or lower arm. The lower arm gate driving circuit has two driving command input functions having different reference potentials, one function inputs the driving commands from the first fail-safe circuit, and the other function inputs the driving commands from the second fail-safe circuit.Type: ApplicationFiled: February 21, 2020Publication date: June 18, 2020Inventor: Masaki HIRAKATA
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Publication number: 20200012205Abstract: An electrophotographic photoreceptor includes a conductive substrate; an undercoat layer on the conductive substrate; a charge generating layer on the undercoat layer; a charge transporting layer on the charge generating layer; and an inorganic protective layer on the charge transporting layer. The undercoat layer, the charge transporting layer, and the inorganic protective layer each have a film elastic modulus of 5 GPa or more.Type: ApplicationFiled: January 29, 2019Publication date: January 9, 2020Applicant: FUJI XEROX CO.,LTD.Inventors: Yoichi KIGOSHI, Takeshi IWANAGA, Nobuyuki TORIGOE, Masaki HIRAKATA, Hideya KATSUHARA, Keisuke KUSANO
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Publication number: 20190346781Abstract: An electrophotographic photoreceptor of an exemplary embodiment includes a conductive substrate, an undercoat layer on the conductive substrate, a charge generating layer on the undercoat layer, a charge transporting layer on the charge generating layer, and an inorganic protective layer on the charge transporting layer, in which formula: 0<A/B<0.5 is satisfied, where A represents a thickness of a layer having the lowest film elastic modulus among the layers disposed on the conductive substrate other than the charge generating layer, and B represents a total thickness of the layers disposed on the conductive substrate.Type: ApplicationFiled: February 6, 2019Publication date: November 14, 2019Applicant: FUJI XEROX CO., LTD.Inventors: Hideya KATSUHARA, Takeshi IWANAGA, Masaki HIRAKATA, Nobuyuki TORIGOE, Yoichi KIGOSHI
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Publication number: 20190302632Abstract: Provided is an electrophotographic photoreceptor including: a conductive substrate; a single-layer type photosensitive layer that is provided on the conductive substrate; an inorganic protective layer that is provided on the single-layer type photosensitive layer; wherein layers that are interposed between the conductive substrate and the inorganic protective layer have a total thickness of 10 ?m to 25 ?m.Type: ApplicationFiled: July 30, 2018Publication date: October 3, 2019Applicant: FUJI XEROX CO., LTD.Inventors: Nobuyuki TORIGOE, Takeshi IWANAGA, Masaki HIRAKATA, Hideya KATSUHARA, Yoichi KIGOSHI, Yukimi KAWABATA
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Patent number: 10317809Abstract: An image forming apparatus includes a photoreceptor that includes a conductive substrate, a photosensitive layer, and an inorganic surface layer arranged in that order, the inorganic surface layer containing a group 13 element and oxygen; a charging unit; an electrostatic image-forming unit; a developing unit; a transfer unit; a cleaning unit that performs cleaning by causing the cleaning blade to contact the surface of the photoreceptor; and a supply unit that supplies a fatty acid metal salt to a position where the cleaning blade in the cleaning unit contacts the photoreceptor. When the fatty acid metal salt is supplied, a portion of the surface of the photoreceptor downstream of the supply unit and upstream of the cleaning unit in a rotating direction of the photoreceptor is covered with a metal derived from the fatty acid metal salt at a coverage of about 40% or more.Type: GrantFiled: March 8, 2018Date of Patent: June 11, 2019Assignee: FUJI XEROX CO., LTD.Inventors: Masaki Hirakata, Hideya Katsuhara, Nobuyuki Torigoe, Yasutaka Matsumoto, Takeshi Iwanaga
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Publication number: 20190094722Abstract: An image forming apparatus includes a photoreceptor that includes a conductive substrate, a photosensitive layer, and an inorganic surface layer arranged in that order, the inorganic surface layer containing a group 13 element and oxygen; a charging unit; an electrostatic image-forming unit; a developing unit; a transfer unit; a cleaning unit that performs cleaning by causing the cleaning blade to contact the surface of the photoreceptor; and a supply unit that supplies a fatty acid metal salt to a position where the cleaning blade in the cleaning unit contacts the photoreceptor. When the fatty acid metal salt is supplied, a portion of the surface of the photoreceptor downstream of the supply unit and upstream of the cleaning unit in a rotating direction of the photoreceptor is covered with a metal derived from the fatty acid metal salt at a coverage of about 40% or more.Type: ApplicationFiled: March 8, 2018Publication date: March 28, 2019Applicant: FUJI XEROX CO., LTD.Inventors: Masaki HIRAKATA, Hideya KATSUHARA, Nobuyuki TORIGOE, Yasutaka MATSUMOTO, Takeshi IWANAGA
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Patent number: 10185276Abstract: An image forming apparatus includes an electrophotographic photoreceptor, a charging device, an electrostatic latent image forming device, a developing device, a transfer device, and a cleaning device, and further includes an intercepting device that includes an intercepting member separated from the electrophotographic photoreceptor by a gap so that a distance from the surface of the electrophotographic photoreceptor to the intercepting member is about 0.3 to 0.9 (inclusive) times a volume-average particle size of toner particles. The intercepting member is used to intercept residual toner particles at a position downstream of the transfer device and upstream of the cleaning device in a rotation direction of the electrophotographic photoreceptor, the residual toner particles remaining on the surface of the electrophotographic photoreceptor.Type: GrantFiled: March 8, 2017Date of Patent: January 22, 2019Assignee: FUJI XEROX CO., LTD.Inventors: Masaki Hirakata, Takashi Imai
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Publication number: 20180331616Abstract: A power conversion device, that includes a drive circuit 11a that drives a switching element 4 included in an upper-arm for one of three phases, a drive circuit 11b that drives a switching element 5 included in a lower-arm for the one phase, and a control circuit 9 that transmits a control signal to the drive circuits 11a, 11b, is provided. The power conversion device includes power supply circuits 12a, 12b that provide power to the drive circuits 11a, 11b, respectively, a low-voltage power supply 6 that supplies power to one of the power supply circuits, 12a, and a high-voltage power supply 1 that supplies power to the other of the power supply circuits, 12b. Accordingly, it is possible to reliably protect a system: by realizing minimal redundancy of the power supply, the power supply generation circuit, etc.; and by realizing the short-circuit mode at the time of error occurrence.Type: ApplicationFiled: July 23, 2018Publication date: November 15, 2018Inventors: Masaki HIRAKATA, Akihiro ODAKA