Patents by Inventor Ryuzo Kawabata

Ryuzo Kawabata 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: 11872028
    Abstract: To perform respiratory monitoring and cardiac-output measurement on general patients, an aspect of a biological measurement apparatus includes: at least two electrodes that are attached to a living body; a power supply that causes an AC current to flow between the two electrodes; at least two coils that are placed so as to sandwich a line linking the two electrodes, and detect a magnetic field related to a change in the AC current accompanying a change in impedance of the living body; and a detection circuit that performs addition or subtraction of signals related to the magnetic field detected with the two coils, and outputs the signals as a change in the impedance.
    Type: Grant
    Filed: August 7, 2020
    Date of Patent: January 16, 2024
    Assignee: HITACHI, LTD
    Inventors: Akihiko Kandori, Ryuzo Kawabata, Kuniomi Ogata, Takako Mizoguchi, Tsukasa Funane
  • Publication number: 20230399036
    Abstract: A rail state monitoring apparatus includes: a plurality of detection devices provided on a train that travels on left and right railroad rails forming a track, and a processing device. The train is composed of one or a plurality of vehicles. For each of the plurality of detection devices, the detection device has a magnetic sensor unit group that is one or more magnetic sensor units facing the railroad rail, the magnetic sensor unit detects a peculiar point when the magnetic sensor unit passes over the peculiar point on the railroad rail, and the detection device outputs a signal based on a result of the detection by the magnetic sensor unit group. The plurality of detection devices include detection devices provided symmetrically on right and left sides of the train and/or detection devices provided on front and rear sides of the train.
    Type: Application
    Filed: April 21, 2023
    Publication date: December 14, 2023
    Inventors: Ryuzo KAWABATA, Kuniomi OGATA
  • Patent number: 10989694
    Abstract: Provided is a rail inspection system capable of accurately detecting a defect of a railroad rail. The system includes: a sensor part group that has a plurality of sensor parts having receiver coils, and first oscillator coils and second oscillator coils corresponding to the receiver coils being arranged in a line parallel in a width direction of a railroad rail to be inspected; an oscillation part that supplies an oscillation signal to each of the first oscillator coils and the second oscillator coils; and a detection part group that has a plurality of detection parts to detect, with respect to an output signal from each of the receiver coils when the sensor part group moves in a laying direction of the railroad rail, a first inspection signal corresponding to a first phase of the output signal and a second inspection signal corresponding to a second phase of the output signal.
    Type: Grant
    Filed: September 11, 2017
    Date of Patent: April 27, 2021
    Assignee: Hitachi High-Tech Fine Systems Corporation
    Inventors: Ryuzo Kawabata, Hiroshi Suzuki, Kenji Yamamoto, Akihiko Kandori
  • Publication number: 20210076978
    Abstract: To perform respiratory monitoring and cardiac-output measurement on general patients, an aspect of a biological measurement apparatus includes: at least two electrodes that are attached to a living body; a power supply that causes an AC current to flow between the two electrodes; at least two coils that are placed so as to sandwich a line linking the two electrodes, and detect a magnetic field related to a change in the AC current accompanying a change in impedance of the living body; and a detection circuit that performs addition or subtraction of signals related to the magnetic field detected with the two coils, and outputs the signals as a change in the impedance.
    Type: Application
    Filed: August 7, 2020
    Publication date: March 18, 2021
    Applicant: HITACHI, LTD.
    Inventors: Akihiko KANDORI, Ryuzo KAWABATA, Kuniomi OGATA, Takako MIZOGUCHI, Tsukasa FUNANE
  • Patent number: 10739311
    Abstract: In a rail inspection system, a positional deviation can be detected with accuracy. The rail inspection system includes a first sensor unit which is disposed to face a rail for a vehicle, and includes at least one receiver coil and at least one oscillation coil which are arranged in an arrangement direction intersecting with a layout direction of the rail, an AC voltage source which applies AC voltage to the oscillation coil, and a displacement detection unit which detects a displacement between the rail and the first sensor unit based on an induced voltage of the receiver coil. The first sensor unit is configured such that, when the displacement is a first displacement, a first maximum value appears in the induced voltage, and when the displacement is a second displacement, a second maximum value of which a phase is reversed against the first maximum value appears in the induced voltage.
    Type: Grant
    Filed: June 9, 2017
    Date of Patent: August 11, 2020
    Assignee: HITACHI HIGH-TECH FINE SYSTEMS CORPORATION
    Inventors: Ryuzo Kawabata, Akihiko Kandori
  • Patent number: 10591442
    Abstract: The present invention addresses the problem of checking defects of a rail for a vehicle with a high SN ratio. A detection device (2) for generating check data related to the defects of a railway rail RR (rail for a vehicle) is provided with an oscillating coil C1 (211) and an oscillating coil C2 (211) that are disposed on the surface opposite the railway rail RR and generate AC magnetic fields whose directions are opposite to each other, and a receiving coil (212) that is positioned between or in the vicinity the oscillation coils and that outputs a magnetic field waveform based on the magnetic fields received from the oscillating coils as the check data.
    Type: Grant
    Filed: March 11, 2016
    Date of Patent: March 17, 2020
    Assignee: Hitachi High-Technologies Corporation
    Inventors: Ryuzo Kawabata, Akihiko Kandori, Noritake Shizawa, Kenji Yamamoto, Hiroyuki Kanda
  • Publication number: 20190302057
    Abstract: Provided is a rail inspection system capable of accurately detecting a defect of a railroad rail. The system includes: a sensor part group that has a plurality of sensor parts having receiver coils, and first oscillator coils and second oscillator coils corresponding to the receiver coils being arranged in a line parallel in a width direction of a railroad rail to be inspected; an oscillation part that supplies an oscillation signal to each of the first oscillator coils and the second oscillator coils; and a detection part group that has a plurality of detection parts to detect, with respect to an output signal from each of the receiver coils when the sensor part group moves in a laying direction of the railroad rail, a first inspection signal corresponding to a first phase of the output signal and a second inspection signal corresponding to a second phase of the output signal.
    Type: Application
    Filed: September 11, 2017
    Publication date: October 3, 2019
    Inventors: Ryuzo KAWABATA, Hiroshi SUZUKI, Kenji YAMAMOTO, Akihiko KANDORI
  • Publication number: 20190170692
    Abstract: In a rail inspection system, a positional deviation can be detected with accuracy. The rail inspection system includes a first sensor unit which is disposed to face a rail for a vehicle, and includes at least one receiver coil and at least one oscillation coil which are arranged in an arrangement direction intersecting with a layout direction of the rail, an AC voltage source which applies AC voltage to the oscillation coil, and a displacement detection unit which detects a displacement between the rail and the first sensor unit based on an induced voltage of the receiver coil. The first sensor unit is configured such that, when the displacement is a first displacement, a first maximum value appears in the induced voltage, and when the displacement is a second displacement, a second maximum value of which a phase is reversed against the first maximum value appears in the induced voltage.
    Type: Application
    Filed: June 9, 2017
    Publication date: June 6, 2019
    Applicant: HITACHI HIGH-TECH FINE SYSTEMS CORPORATION
    Inventors: Ryuzo KAWABATA, Akihiko KANDORI
  • Patent number: 10247789
    Abstract: An object of the invention is to reduce 1/f noise and white noise at the same time by integrally reducing noise of an MR sensor and noise of an operation circuit part. A magnetoresistive sensor according to the invention includes a plurality of magnetoresistive sensor parts each having a bridge circuit in which four magnetoresistive elements are connected, and outputs of the respective magnetoresistive sensor parts are connected in parallel to one another to an input of an amplifier circuit (see FIG. 2).
    Type: Grant
    Filed: January 18, 2017
    Date of Patent: April 2, 2019
    Assignee: Hitachi, Ltd.
    Inventors: Akihiko Kandori, Yusuke Seki, Ryuzo Kawabata
  • Patent number: 10215816
    Abstract: The present invention addresses the problem of stabilizing signals in magnetic field measurement using optical pumping. In order to solve the problem, disclosed is a light source apparatus (10) that is characterized in having: a light intensity fluctuation detection circuit (130) that detects intensity fluctuation of light outputted from a laser output unit (11); and an acousto-optic modulator (121) that corrects light intensity on the basis of light intensity fluctuation detected by means of the light intensity fluctuation detection circuit (130) such that the light intensity is constant Furthermore, a magnetic field measuring apparatus of the present invention is characterized in having: one sensor unit that passes therethrough light outputted from a light source unit: and a signal control processor that eliminates the light intensity fluctuation on the basis of two lights passed through the sensor unit.
    Type: Grant
    Filed: December 3, 2013
    Date of Patent: February 26, 2019
    Assignee: Hitachi, Ltd.
    Inventors: Ryuzo Kawabata, Akihiko Kandori
  • Patent number: 10162021
    Abstract: A magnetic measurement device has a magnetic sensor including a glass cell having alkali metal gas encapsulated therein that is configured to detect a magnetic field using a magneto-optical characteristic of spin-polarized alkali metal. A laser light source is configured to generate pump light introduced into the magnetic sensor and a coil provided in the same magnetically shielded space as the magnetic sensor is configured to apply a static magnetic field and a RF magnetic field to the magnetic sensor. A signal processor is configured to perform lock-in detection of a light detection signal transmitted through the glass cell of the magnetic sensor, control an intensity of the static magnetic field and a frequency of the RF magnetic field generated by the coil according to a lock-in detection output, and obtain a measurement signal reflecting a magnetic field intensity of an object to be measured in the magnetically shielded space.
    Type: Grant
    Filed: August 2, 2013
    Date of Patent: December 25, 2018
    Assignee: Hitachi, Ltd.
    Inventors: Ryuzo Kawabata, Akihiko Kandori, Taro Osabe, Seiichi Suzuki, Yuudai Kamada
  • Publication number: 20180172639
    Abstract: The present invention addresses the problem of checking defects of a rail for a vehicle with a high SN ratio. A detection device (2) for generating check data related to the defects of a railway rail RR (rail for a vehicle) is provided with an oscillating coil C1 (211) and an oscillating coil C2 (211) that are disposed on the surface opposite the railway rail RR and generate AC magnetic fields whose directions are opposite to each other, and a receiving coil (212) that is positioned between or in the vicinity the oscillation coils and that outputs a magnetic field waveform based on the magnetic fields received from the oscillating coils as the check data.
    Type: Application
    Filed: March 11, 2016
    Publication date: June 21, 2018
    Inventors: Ryuzo KAWABATA, Akihiko KANDORI, Noritake SHIZAWA, Kenji YAMAMOTO, Hiroyuki KANDA
  • Publication number: 20170168123
    Abstract: An object of the invention is to reduce 1/f noise and white noise at the same time by integrally reducing noise of an MR sensor and noise of an operation circuit part. A magnetoresistive sensor according to the invention includes a plurality of magnetoresistive sensor parts each having a bridge circuit in which four magnetoresistive elements are connected, and outputs of the respective magnetoresistive sensor parts are connected in parallel to one another to an input of an amplifier circuit (see FIG. 2).
    Type: Application
    Filed: January 18, 2017
    Publication date: June 15, 2017
    Inventors: Akihiko Kandori, Yusuke Seki, Ryuzo Kawabata
  • Publication number: 20160313417
    Abstract: The present invention addresses the problem of stabilizing signals in magnetic field measurement using optical pumping. In order to solve the problem, disclosed is a light source apparatus (10) that is characterized in having: a light intensity fluctuation detection circuit (130) that detects intensity fluctuation of light outputted from a laser output unit (11); and an acousto-optic modulator (121) that corrects light intensity on the basis of light intensity fluctuation detected by means of the light intensity fluctuation detection circuit (130) such that the light intensity is constant Furthermore, a magnetic field measuring apparatus of the present invention is characterized in having: one sensor unit that passes therethrough light outputted from a light source unit: and a signal control processor that eliminates the light intensity fluctuation on the basis of two lights passed through the sensor unit.
    Type: Application
    Filed: December 3, 2013
    Publication date: October 27, 2016
    Inventors: Ryuzo KAWABATA, Akihiko KANDORI
  • Patent number: 9468581
    Abstract: A compression depth calculation system is configured to calculate the compression depth which is a magnitude of depression of the compressed object generated by the compression and includes a measuring apparatus to be mounted on the object, and a compression depth calculating apparatus is configured to calculate the compression depth on the basis of information from the measuring apparatus. The compression depth calculation apparatus calculates a coefficient of transformation on the basis of a second-order differential waveform created for the information acquired from a magnetic sensor and acceleration information acquired from an acceleration sensor, creates a displacement waveform of a compressed portion by multiplying the acquired information by the coefficient of transformation, and calculates the compression depth on the basis of the displacement waveform.
    Type: Grant
    Filed: November 28, 2011
    Date of Patent: October 18, 2016
    Assignee: HITACHI, LTD.
    Inventors: Akihiko Kandori, Kuniomi Ogata, Ryuzo Kawabata, Yuko Sano, Takako Mizoguchi
  • Patent number: 9448204
    Abstract: In a magnetic immunoassay using AC magnetic susceptibility measurement, a signal from non-coupled magnetic particles is prevented to mix with a desired measurement signal from magnetic particles coupled with an object to be measured. A sample vessel in which a mixed solution of an inspection objective sample and the magnetic particles are included is carried by a sample support, such that a precipitation of the magnetic particle coupled with the object to be measured dispersed in the solution by a magnetic field from a dissociating coil is promoted. Next, the sample vessel is carried to the magnetizing coil and the magnetic signal from the non-coupled magnetic particle remaining in a supernatant in the vessel is peculiarly measured by an MR sensor to perform AC magnetic susceptibility measurement with high precision.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: September 20, 2016
    Assignee: HITACHI, LTD.
    Inventors: Takako Mizoguchi, Ryuzo Kawabata, Akihiko Kandori
  • Publication number: 20160169989
    Abstract: An object of the present invention is to provide a technique to improve a manufacturing yield of a gas cell included in a magnetic field measuring apparatus. A gas cell GC according to an embodiment is characterized in that, for example, a cavity CAV includes an opening OP1 and an opening OP2, a plane size of the opening OP1 becomes larger than a plane size of the opening OP2 in the openings OP1 and OP2 included in the cavity CAV. Especially, according to the embodiment, the opening OP2 is included in the opening OP1 in plan view. Consequently, a width of the opening OP1 coming into contact with an upper surface of the sealing substrate 1S becomes larger than a width of the opening OP2 coming into contact with a lower surface of the sealing substrate 2S.
    Type: Application
    Filed: August 8, 2013
    Publication date: June 16, 2016
    Applicant: Hitachi, Ltd.
    Inventors: Seiichi SUZUKI, Taro OSABE, Yudai KAMADA, Ryuzo KAWABATA, Akihiko KANDORI
  • Patent number: 9366735
    Abstract: Stable magnetic field measurement is enabled without collapse of polarization or fluctuation of intensity of a laser beam incident on a glass cell of an optical pumping magnetic sensor. Excitation light generated with a light source, having optimized light intensity and polarized wave, through frequency stabilization, intensity control and polarized-wave control, is introduced via a polarized wave holding optical fiber to a magnetic sensor provided in a magnetic shield, and magnetic field measurement is performed by optical pumping using magneto-optical properties of spin-polarized alkali metal. The magnetic sensor has a structure where a lens, a polarization optical device, the glass cell and a photodetector, are integrally accommodated in a non-magnetic case.
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: June 14, 2016
    Assignee: Hitachi, Ltd.
    Inventors: Ryuzo Kawabata, Akihiko Kandori, Taro Osabe, Seiichi Suzuki, Yudai Kamada
  • Publication number: 20160146909
    Abstract: A magnetic measurement device has a magnetic sensor including a glass cell having alkali metal gas encapsulated therein that is configured to detect a magnetic field using a magneto-optical characteristic of spin-polarized alkali metal. A laser light source is configured to generate pump light introduced into the magnetic sensor and a coil provided in the same magnetically shielded space as the magnetic sensor is configured to apply a static magnetic field and a RF magnetic field to the magnetic sensor. A signal processor is configured to perform lock-in detection of a light detection signal transmitted through the glass cell of the magnetic sensor, control an intensity of the static magnetic field and a frequency of the RF magnetic field generated by the coil according to a lock-in detection output, and obtain a measurement signal reflecting a magnetic field intensity of an object to be measured in the magnetically shielded space.
    Type: Application
    Filed: August 2, 2013
    Publication date: May 26, 2016
    Inventors: Ryuzo KAWABATA, Akihiko KANDORI, Taro OSABE, Seiichi SUZUKI, Yuudai KAMADA
  • Patent number: 9310447
    Abstract: In order to provide a magnetic field measuring apparatus facilitating the pressure control in a gas cell, or capable of inspecting the internal pressure of the gas cell without using any special process, the magnetic field measuring apparatus is configured such that a process layer of the magnetic field measuring apparatus has such a structure that includes a first hollow portion and a second hollow portion provided opposed to first hollow portion with a first isolation wall interposed therebetween. Alternatively, a method for manufacturing the magnetic field measuring apparatus includes breaking the first isolation wall after generating alkali metal (FIG. 17 and FIG. 20).
    Type: Grant
    Filed: November 18, 2011
    Date of Patent: April 12, 2016
    Assignee: HITACHI, LTD.
    Inventors: Yudai Kamada, Taro Osabe, Seiichi Suzuki, Akihiko Kandori, Ryuzo Kawabata