Patents by Inventor Keiichi Fujii

Keiichi Fujii 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).

  • Patent number: 11965933
    Abstract: A battery monitoring device includes: a pair of terminals for measuring voltage or current of a battery, and to which a filter unit including a capacitive element is connected; an AD converter that measures a waveform of voltage between the terminals during charging or discharging of the capacitive element; and a time constant calculation unit that calculates a time constant of the filter unit based on the waveform measured. The AD converter is, for example, a first AD converter or a second AD converter. The filter unit is, for example, a first filter unit or a second filter unit.
    Type: Grant
    Filed: December 23, 2020
    Date of Patent: April 23, 2024
    Assignee: NUVOTON TECHNOLOGY CORPORATION JAPAN
    Inventors: Kazuo Matsukawa, Yu Okada, Yosuke Goto, Hitoshi Kobayashi, Keiichi Fujii
  • Publication number: 20240110992
    Abstract: A battery anomaly detection device includes: an alternating-current (AC) impedance measurer that measures AC impedance of a battery cell; and an anomaly determiner that determines whether the AC impedance is within a reference range, and when the AC impedance is not within the reference range, determines that the battery cell is an anomalous cell.
    Type: Application
    Filed: December 1, 2023
    Publication date: April 4, 2024
    Inventors: Akira KAWABE, Hitoshi KOBAYASHI, Keiichi FUJII
  • Patent number: 11946847
    Abstract: An extracellular potential measurement device includes multiple insulating films each of which is made from an electric insulating material, the insulating films being stacked and bonded to each other; and multiple electrode wires each of which is made from an electroconductive material, the electrode wires being arranged in multiple heights. Each of the electrode wires is interposed between an upper insulating film and a lower insulating film. Each of the insulating films, except for a lowermost insulating film, has an opening penetrating the insulating film. The opening in a lower insulating film has a size that is less than that of the opening in an upper insulating film, the openings in the insulating films being overlapped to form a recess having a size reducing downward, the recess being adapted to store a collection of cells. Each of the electrode wires has an end that is located near an opening in an insulating film that is immediately below the electrode wire, the ends being exposed in the recess.
    Type: Grant
    Filed: October 1, 2020
    Date of Patent: April 2, 2024
    Assignees: NOK CORPORATION, THE UNIVERSITY OF TOKYO
    Inventors: Takayuki Komori, Keiichi Miyajima, SooHyeon Kim, Teruo Fujii, Shinji Okawa
  • Publication number: 20240094303
    Abstract: A battery state estimation device includes: a first state of charge (SOC) calculator that calculates a first SOC using a first method that uses the battery model parameter of a battery; a second SOC calculator that calculates a second SOC using a second method different from the first method; an alternating-current (AC) impedance measurement unit that measures the AC impedance of the battery when the error between the first SOC and the second SOC is greater than a predetermined threshold; and a battery model parameter calculator that calculates a battery model parameter using the measured AC impedance. The first SOC calculator recalculates the first SOC using the battery model parameter calculated.
    Type: Application
    Filed: November 30, 2023
    Publication date: March 21, 2024
    Inventors: Keiichi FUJII, Hitoshi KOBAYASHI, Tomohiro OKACHI
  • Patent number: 11933854
    Abstract: A battery management circuit includes: a reference signal generator that generates a first reference frequency signal and a second reference frequency signal having a phase different from a phase of the first reference frequency signal; an alternating-current superimposer that superimposes an alternating current on the secondary battery, the alternating current having a frequency component of the first reference frequency signal; a voltage measurer that measures a voltage of the secondary battery by performing sampling using a frequency; a current measurer that measures a current of the secondary battery by performing sampling using a frequency; and a converter that converts each of results of measurements by the voltage measurer and the current measurer into a complex voltage and a complex current, by multiplying the result of the measurement by the first reference frequency signal and the second reference frequency signal.
    Type: Grant
    Filed: December 21, 2021
    Date of Patent: March 19, 2024
    Assignee: NUVOTON TECHNOLOGY CORPORATION JAPAN
    Inventors: Yu Okada, Hitoshi Kobayashi, Keiichi Fujii
  • Patent number: 11467219
    Abstract: A battery monitoring device includes a first reference resistor disposed in a path different from a path of current flowing from a battery to a load; a transistor for passing current from the battery to the first reference resistor; and an integrated circuit. The integrated circuit includes: a current measurement unit that measures a first current flowing through the first reference resistor; a voltage measurement unit that measures a first voltage of the battery; and a first calculation unit that calculates an AC impedance of the battery based on the first current measured and the first voltage measured.
    Type: Grant
    Filed: December 23, 2020
    Date of Patent: October 11, 2022
    Assignee: NUVOTON TECHNOLOGY CORPORATION JAPAN
    Inventors: Kazuo Matsukawa, Yu Okada, Yoshikazu Makabe, Hitoshi Kobayashi, Takeshi Misaku, Keiichi Fujii
  • Publication number: 20220120817
    Abstract: A battery management circuit includes: a reference signal generator that generates a first reference frequency signal and a second reference frequency signal having a phase different from a phase of the first reference frequency signal; an alternating-current superimposer that superimposes an alternating current on the secondary battery, the alternating current having a frequency component of the first reference frequency signal; a voltage measurer that measures a voltage of the secondary battery by performing sampling using a frequency; a current measurer that measures a current of the secondary battery by performing sampling using a frequency; and a converter that converts each of results of measurements by the voltage measurer and the current measurer into a complex voltage and a complex current, by multiplying the result of the measurement by the first reference frequency signal and the second reference frequency signal.
    Type: Application
    Filed: December 21, 2021
    Publication date: April 21, 2022
    Inventors: Yu OKADA, Hitoshi KOBAYASHI, Keiichi FUJII
  • Publication number: 20210109160
    Abstract: A battery monitoring device includes a first reference resistor disposed in a path different from a path of current flowing from a battery to a load; a transistor for passing current from the battery to the first reference resistor; and an integrated circuit. The integrated circuit includes: a current measurement unit that measures a first current flowing through the first reference resistor; a voltage measurement unit that measures a first voltage of the battery; and a first calculation unit that calculates an AC impedance of the battery based on the first current measured and the first voltage measured.
    Type: Application
    Filed: December 23, 2020
    Publication date: April 15, 2021
    Inventors: Kazuo MATSUKAWA, Yu OKADA, Yoshikazu MAKABE, Hitoshi KOBAYASHI, Takeshi MISAKU, Keiichi FUJII
  • Publication number: 20210109162
    Abstract: A battery monitoring device includes: a pair of terminals for measuring voltage or current of a battery, and to which a filter unit including a capacitive element is connected; an AD converter that measures a waveform of voltage between the terminals during charging or discharging of the capacitive element; and a time constant calculation unit that calculates a time constant of the filter unit based on the waveform measured. The AD converter is, for example, a first AD converter or a second AD converter. The filter unit is, for example, a first filter unit or a second filter unit.
    Type: Application
    Filed: December 23, 2020
    Publication date: April 15, 2021
    Inventors: Kazuo MATSUKAWA, Yu OKADA, Yosuke GOTO, Hitoshi KOBAYASHI, Keiichi FUJII
  • Patent number: 10471266
    Abstract: A hermetic feedthrough for an implantable medical device includes a sheet having a hole defined therethrough, wherein the sheet comprises a first material that is an electrically insulative ceramic comprising alumina. The feedthrough further includes a second material substantially filling the hole so as to form a conduit, the second material having platinum and an additive that includes alumina. The second material does not include SiO2, MgO, or CaO. The first and second materials have a co-fired bond therebetween, the co-fired bond hermetically sealing the hole.
    Type: Grant
    Filed: July 12, 2016
    Date of Patent: November 12, 2019
    Assignees: MEDTRONIC, INC., KYOCERA CORPORATION
    Inventors: Kengo Morioka, Keiichi Fujii, Arne Knudsen, Shingo Satou, Hidekazu Otomaru, Hiroshi Makino, Andrew Thom, Markus Reiterer, Gordon Munns, Thomas Miltich, Joyce Yamamoto
  • Publication number: 20160317821
    Abstract: A method of manufacturing an implantable medical device includes manufacturing a hermetic feedthrough by providing a first sheet of unfired ceramic material, forming one or more holes through the sheet, inserting a first conductive material into one of the holes, and forming a pad in electrical contact with the first conductive material in one of the holes, wherein the pad comprises a plurality of layers and has a thickness of at least 50 micrometers, at least one layer comprising a second conductive material having a different composition than the first conductive material. The method further includes co-firing the unfired ceramic material, the first conductive material, and the second conductive material. The method further includes coupling the feedthrough to an encasement structure of the implantable medical device.
    Type: Application
    Filed: July 12, 2016
    Publication date: November 3, 2016
    Applicants: Medtronic, Inc., Kyocera Corporation
    Inventors: Kengo Morioka, Keiichi Fujii, Arne Knudsen, Shingo Satou, Hidekazu Otomaru, Hiroshi Makino, Andrew Thom, Markus Reiterer, Gordon Munns, Thomas Miltich, Joyce Yamamoto
  • Patent number: 9418778
    Abstract: A hermetic feedthrough for an implantable medical device includes an insulator, a conduit configured to conduct electricity through the insulator, and a ferrule coupled to the insulator. The insulator is formed from a ceramic material and the conduit and insulator have a co-fired bond therebetween, which hermetically seals the conduit with the insulator. The insulator is elongate and has opposing ends that include flat surfaces and the ferrule includes a frame for receiving the insulator.
    Type: Grant
    Filed: March 10, 2014
    Date of Patent: August 16, 2016
    Assignees: MEDTRONIC, INC., KYOCERA CORPORATION
    Inventors: Kengo Morioka, Keiichi Fujii, Arne Knudsen, Shingo Satou, Hidekazu Otomaru, Hiroshi Makino, Andrew Thom, Markus Reiterer, Gordon Munns, Thomas Miltich, Joyce Yamamoto
  • Patent number: 9008779
    Abstract: A hermetic feedthrough for an implantable medical device includes an insulator body and a ferrule. The insulator body includes ceramic material and one or more electrically conductive conduits extending through the insulator body. The insulator is disposed in an opening of the ferrule. The insulator body includes a plurality of substantially flat surfaces that each include a plurality of edges. A rounded corner extends between adjacent edges of any two adjacent substantially flat surfaces. Each corner between any two adjacent substantially flat surfaces that face toward the ferrule has an average radius that is less than approximately 25% of a length of the corresponding edges.
    Type: Grant
    Filed: February 7, 2014
    Date of Patent: April 14, 2015
    Assignees: Medtronic, Inc., Kyocera Corporation
    Inventors: Kengo Morioka, Keiichi Fujii, Arne Knudsen, Shingo Satou, Hidekazu Otomaru, Hiroshi Makino, Andrew Thom, Markus Reiterer, Gordon Munns, Thomas Miltich, Joyce Yamamoto
  • Publication number: 20140322426
    Abstract: A method of extracting a coffee liquid includes the step of extracting crashed coffee beans using an extraction aqueous solution containing a fruit sugar condensation compound formed of a plurality of fructose molecules through condensation.
    Type: Application
    Filed: May 1, 2014
    Publication date: October 30, 2014
    Inventor: Keiichi FUJII
  • Publication number: 20140305694
    Abstract: A hermetic feedthrough for an implantable medical device includes an insulator, a conduit configured to conduct electricity through the insulator, and a ferrule coupled to the insulator. The insulator is formed from a ceramic material and the conduit and insulator have a co-fired bond therebetween, which hermetically seals the conduit with the insulator. The insulator is elongate and has opposing ends that include flat surfaces and the ferrule includes a frame for receiving the insulator.
    Type: Application
    Filed: March 10, 2014
    Publication date: October 16, 2014
    Applicants: Medtronic, Inc., Kyocera Corporation
    Inventors: Kengo Morioka, Keiichi Fujii, Arne Knudsen, Shingo Satou, Hidekazu Otomaru, Hiroshi Makino, Andrew Thom, Markus Reiterer, Gordon Munns, Thomas Miltich, Joyce Yamamoto
  • Publication number: 20140151114
    Abstract: A hermetic feedthrough for an implantable medical device includes an insulator body and a ferrule. The insulator body includes ceramic material and one or more electrically conductive conduits extending through the insulator body. The insulator is disposed in an opening of the ferrule. The insulator body includes a plurality of substantially flat surfaces that each include a plurality of edges. A rounded corner extends between adjacent edges of any two adjacent substantially flat surfaces. Each corner between any two adjacent substantially flat surfaces that face toward the ferrule has an average radius that is less than approximately 25% of a length of the corresponding edges.
    Type: Application
    Filed: February 7, 2014
    Publication date: June 5, 2014
    Applicants: Medtronic, Inc., Kyocera Corporation
    Inventors: Kengo Morioka, Keiichi Fujii, Arne Knudsen, Shingo Satou, Hidekazu Otomaru, Hiroshi Makino, Andrew Thom, Markus Reiterer, Gordon Munns, Thomas Miltich, Joyce Yamamoto
  • Patent number: 8670829
    Abstract: A hermetic feedthrough for an implantable medical device includes an insulator, a conduit configured to conduct electricity through the insulator, and a ferrule coupled to the insulator. The insulator is formed from a ceramic material and the conduit and insulator have a co-fired bond therebetween, which hermetically seals the conduit with the insulator. The insulator is elongate and has opposing ends that include flat surfaces and the ferrule includes a frame for receiving the insulator.
    Type: Grant
    Filed: August 2, 2011
    Date of Patent: March 11, 2014
    Assignees: Medtronic, Inc., Kyocera Corporation
    Inventors: Kengo Morioka, Keiichi Fujii, Arne Knudsen, Shingo Satou, Hidekazu Otomaru, Hiroshi Makino, Andrew Thom, Markus Reiterer, Gordon Munns, Thomas Miltich, Joyce Yamamoto
  • Publication number: 20130032392
    Abstract: A hermetic feedthrough for an implantable medical device includes an insulator, a conduit configured to conduct electricity through the insulator, and a ferrule coupled to the insulator. The insulator is formed from a ceramic material and the conduit and insulator have a co-fired bond therebetween, which hermetically seals the conduit with the insulator. The insulator is elongate and has opposing ends that include flat surfaces and the ferrule includes a frame for receiving the insulator.
    Type: Application
    Filed: August 2, 2011
    Publication date: February 7, 2013
    Inventors: Kengo Morioka, Keiichi Fujii, Arne Knudsen, Shingo Satou, Hidekazu Otomaru, Hiroshi Makino, Andrew Thom, Markus Reiterer, Gordon Munns, Thomas Miltich, Joyce Yamamoto
  • Patent number: 7940940
    Abstract: A muting circuit of the present invention includes: an input terminal that receives a control signal for allowing switching between ON and OFF of a mute operation; and a muting transistor connected to the input terminal and an output terminal of the amplifier. The muting transistor is a MOS transistor, and a gate is connected to the input terminal, a drain is connected to the output terminal of the amplifier, and a source is grounded. Consequently, a shot noise due to a DC difference caused when a mute state is switched between ON and OFF can be suppressed.
    Type: Grant
    Filed: July 5, 2006
    Date of Patent: May 10, 2011
    Assignee: Panasonic Corporation
    Inventors: Yasunobu Kakumoto, Keiichi Fujii
  • Patent number: 7764797
    Abstract: The present invention detects whether the supply voltage applied to the power supply terminal (3) is used for the dynamic speaker or for the piezoelectric speaker by the power supply voltage detection circuit (10), switches the gain of the amplifier circuit (8) in accordance with the detection result by the gain switching circuit (11) so that the same output power is produced for the same input signal in the respective speaker driving, and amplifies the input signal from the input terminal (5) by the amplifier circuit (8) having the gain to drive a speaker (1) that is connected to the output terminals (6, 7).
    Type: Grant
    Filed: October 24, 2005
    Date of Patent: July 27, 2010
    Assignee: Panasonic Corporation
    Inventors: Makoto Yamamoto, Keiichi Fujii