Patents by Inventor Ikuhiko Ishikawa

Ikuhiko Ishikawa 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: 11330350
    Abstract: A field device according to one aspect of the present invention includes a plurality of types of sensors, at least one converter configured to acquire measured results of the plurality of types of sensors and to convert the measured results into measured information, the measured information being a physical quantity, and an information providing device configured to acquire and store the measured information from the at least one converter and to provide the stored measured information to an outside of the field device in a case that a predetermined condition is satisfied.
    Type: Grant
    Filed: February 15, 2018
    Date of Patent: May 10, 2022
    Assignee: Yokogawa Electric Corporation
    Inventors: Takashi Arai, Yusaku Yoshida, Shuichi Sato, Ikuhiko Ishikawa
  • Patent number: 11105665
    Abstract: An electromagnetic flowmeter measures a flow rate of a liquid of a measurement target that flows in a magnetic field formed within a measurement pipe. The electromagnetic flowmeter includes at least one pair of detection electrodes configured to detect an electromotive force generated due to a flow of the liquid, and configured to output a flow rate signal of a magnitude of the detected electromotive force, a measurement circuit configured to supply an alternating current between the detection electrodes and an earth electrode, and a control calculator configured to control a frequency of the alternating current to be 1 kHz or more, and configured to calculate a conductivity of the liquid whose conductivity is 1 mS/cm or more based on the flow rate signal output when the alternating current flows between the detection electrodes and the earth electrode.
    Type: Grant
    Filed: July 8, 2019
    Date of Patent: August 31, 2021
    Assignee: Yokogawa Electric Corporation
    Inventors: Takashi Arai, Yusaku Yoshida, Shuichi Sato, Ikuhiko Ishikawa
  • Patent number: 10698388
    Abstract: A field device, which measures a physical quantity in a plant or processes the physical quantity, includes: an instruction unit configured to output a verification execution instruction signal for instructing execution of verification of the field device; an operation verifying unit configured to verify an operation of at least one element of the field device in response to the verification execution instruction signal and to verify an operation of the field device based on the verification result; and an output unit configured to output the verification result which is a result of verification of the operation by the operation verifying unit.
    Type: Grant
    Filed: November 30, 2016
    Date of Patent: June 30, 2020
    Assignee: Yokogawa Electric Corporation
    Inventors: Ikuhiko Ishikawa, Toru Shimura, Daisuke Harigane, Shinnosuke Yoshida
  • Publication number: 20200018627
    Abstract: An electromagnetic flowmeter measures a flow rate of a liquid of a measurement target that flows in a magnetic field formed within a measurement pipe. The electromagnetic flowmeter includes at least one pair of detection electrodes configured to detect an electromotive force generated due to a flow of the liquid, and configured to output a flow rate signal of a magnitude of the detected electromotive force, a measurement circuit configured to supply an alternating current between the detection electrodes and an earth electrode, and a control calculator configured to control a frequency of the alternating current to be 1 kHz or more, and configured to calculate a conductivity of the liquid whose conductivity is 1 mS/cm or more based on the flow rate signal output when the alternating current flows between the detection electrodes and the earth electrode.
    Type: Application
    Filed: July 8, 2019
    Publication date: January 16, 2020
    Applicant: Yokogawa Electric Corporation
    Inventors: Takashi ARAI, Yusaku Yoshida, Shuichi Sato, Ikuhiko Ishikawa
  • Publication number: 20180242055
    Abstract: A field device according to one aspect of the present invention includes a plurality of types of sensors, at least one converter configured to acquire measured results of the plurality of types of sensors and to convert the measured results into measured information, the measured information being a physical quantity, and an information providing device configured to acquire and store the measured information from the at least one converter and to provide the stored measured information to an outside of the field device in a case that a predetermined condition is satisfied.
    Type: Application
    Filed: February 15, 2018
    Publication date: August 23, 2018
    Applicant: Yokogawa Electric Corporation
    Inventors: Takashi ARAI, Yusaku YOSHIDA, Shuichi SATO, Ikuhiko ISHIKAWA
  • Patent number: 9683878
    Abstract: An electromagnetic flowmeter applies a magnetic field, which is generated by excitation current, to a fluid to be measured flowing in a measurement tube, and measures a flow rate of the fluid to be measured on the basis of a detection signal to be generated from an electrode provided in the measurement tube. The electromagnetic flowmeter includes an excitation circuit configured to generate the excitation current having a positive excitation period, a negative excitation period and a non-excitation period, and a diagnosis unit configured to detect an abnormality based on characteristics of the fluid to be measured, on the basis of a level of the detection signal in a non-excitation stable period, which is a period in which a differential noise of detection signal to be generated in the non-excitation period converges.
    Type: Grant
    Filed: March 4, 2016
    Date of Patent: June 20, 2017
    Assignee: Yokogawa Electric Corporation
    Inventors: Wandong Li, Ikuhiko Ishikawa, Yuichi Kaneko, Masakazu Saito
  • Publication number: 20170160727
    Abstract: A field device, which measures a physical quantity in a plant or processes the physical quantity, includes: an instruction unit configured to output a verification execution instruction signal for instructing execution of verification of the field device; an operation verifying unit configured to verify an operation of at least one element of the field device in response to the verification execution instruction signal and to verify an operation of the field device based on the verification result; and an output unit configured to output the verification result which is a result of verification of the operation by the operation verifying unit.
    Type: Application
    Filed: November 30, 2016
    Publication date: June 8, 2017
    Applicant: YOKOGAWA ELECTRIC CORPORATION
    Inventors: Ikuhiko ISHIKAWA, Toru SHIMURA, Daisuke HARIGANE, Shinnosuke YOSHIDA
  • Publication number: 20160258793
    Abstract: An electromagnetic flowmeter applies a magnetic field, which is generated by excitation current, to a fluid to be measured flowing in a measurement tube, and measures a flow rate of the fluid to be measured on the basis of a detection signal to be generated from an electrode provided in the measurement tube. The electromagnetic flowmeter includes an excitation circuit configured to generate the excitation current having a positive excitation period, a negative excitation period and a non-excitation period, and a diagnosis unit configured to detect an abnormality based on characteristics of the fluid to be measured, on the basis of a level of the detection signal in a non-excitation stable period, which is a period in which a differential noise of detection signal to be generated in the non-excitation period converges.
    Type: Application
    Filed: March 4, 2016
    Publication date: September 8, 2016
    Applicant: Yokogawa Electric Corporation
    Inventors: Wandong LI, Ikuhiko ISHIKAWA, Yuichi KANEKO, Masakazu SAITO
  • Patent number: 9288289
    Abstract: A portable device maintenance support apparatus includes one set of terminals configured to connect to a hybrid communication network performed based on any one of a plurality of protocols, by a compound signal in which an analog signal is superimposed with a digital signal including at least device information, the hybrid communication network being performed between the portable device maintenance support apparatus and a field device, the one set of terminals being common to the plurality of protocols.
    Type: Grant
    Filed: August 20, 2013
    Date of Patent: March 15, 2016
    Assignee: Yokogawa Electric Corporation
    Inventors: Masafumi Nakamura, Ikuhiko Ishikawa
  • Patent number: 8718152
    Abstract: There is provided a two-wire transmitter which is connected to an external circuit by two transmission lines and which outputs a certain current signal to the external circuit using the external circuit as a power source. The two-wire transmitter includes: a sensor configured to convert a physical quantity into a first electrical signal and output the first electrical signal; a signal processing circuit configured to perform certain processing on the first electrical signal and output a second electrical signal; a constant current circuit configured to determine the certain current signal to be output to the external circuit, based on the second electrical signal; a reference voltage output unit configured to output a reference voltage based on the second electrical signal; and a shunt regulator circuit configured to determine a circuit voltage of the two-wire transmitter based on the reference voltage.
    Type: Grant
    Filed: October 4, 2011
    Date of Patent: May 6, 2014
    Assignee: Yokogawa Electric Corporation
    Inventors: Youichi Iwano, Ikuhiko Ishikawa, Ryou Hagiwara, Kazuyuki Endo
  • Publication number: 20140056173
    Abstract: A portable device maintenance support apparatus includes one set of terminals configured to connect to a hybrid communication network performed based on any one of a plurality of protocols, by a compound signal in which an analog signal is superimposed with a digital signal including at least device information, the hybrid communication network being performed between the portable device maintenance support apparatus and a field device, the one set of terminals being common to the plurality of protocols.
    Type: Application
    Filed: August 20, 2013
    Publication date: February 27, 2014
    Applicant: Yokogawa Electric Corporation
    Inventors: Masafumi NAKAMURA, Ikuhiko ISHIKAWA
  • Publication number: 20120082204
    Abstract: There is provided a two-wire transmitter which is connected to an external circuit by two transmission lines and which outputs a certain current signal to the external circuit using the external circuit as a power source. The two-wire transmitter includes: a sensor configured to convert a physical quantity into a first electrical signal and output the first electrical signal; a signal processing circuit configured to perform certain processing on the first electrical signal and output a second electrical signal; a constant current circuit configured to determine the certain current signal to be output to the external circuit, based on the second electrical signal; a reference voltage output unit configured to output a reference voltage based on the second electrical signal; and a shunt regulator circuit configured to determine a circuit voltage of the two-wire transmitter based on the reference voltage.
    Type: Application
    Filed: October 4, 2011
    Publication date: April 5, 2012
    Applicant: YOKOGAWA ELECTRIC CORPORATION
    Inventors: Youichi IWANO, Ikuhiko ISHIKAWA, Ryou HAGIWARA, Kazuyuki ENDO
  • Patent number: 8047080
    Abstract: An electromagnetic flowmeter for giving a magnetic field to a measurement fluid, detecting an electric signal occurring in the measurement fluid according to the magnetic field, and computing a flow quantity value based on the electric signal includes a zero point measurement section for measuring a zero point of the measurement fluid; a storage section for storing the measured zero point measurement value; a determination section for determining whether or not the difference between the preceding zero point measurement value stored in the storage section and the present zero point measurement value is beyond a predetermined value range; and at least either a transmission section for transmitting the determination result or a display section for displaying the determination result when the determination section determines that the difference is beyond the predetermined value range.
    Type: Grant
    Filed: March 10, 2008
    Date of Patent: November 1, 2011
    Assignee: Yokogawa Electric Corporation
    Inventors: Ikuhiko Ishikawa, Yasumi Koike, Toru Shimura
  • Patent number: 8032257
    Abstract: A field equipment includes: a signal processing section; a first calculation control section for generating a first control signal which controls a start of a signal processing of the signal processing section; first and second insulating sections coupled to the first calculation control section; and a second calculation control section coupled to the first and second insulating sections and the signal processing section, the second calculation control section receiving the first control signal and then transmitting a second control signal corresponding to the first control signal to the signal processing section. The signal processing section generates a processed signal based on the second control signal. The second calculation control section receives the processed signal, then transmits data related to the first signal to the first calculation control section via the second insulating section, and then shifts to a low power consumption mode.
    Type: Grant
    Filed: June 25, 2008
    Date of Patent: October 4, 2011
    Assignee: Yokogawa Electric Corporation
    Inventors: Yasumi Koike, Ikuhiko Ishikawa, Toru Shimura
  • Publication number: 20090024254
    Abstract: A field equipment includes: a signal processing section; a first calculation control section for generating a first control signal which controls a start of a signal processing of the signal processing section; first and second insulating sections coupled to the first calculation control section; and a second calculation control section coupled to the first and second insulating sections and the signal processing section, the second calculation control section receiving the first control signal and then transmitting a second control signal corresponding to the first control signal to the signal processing section. The signal processing section generates a processed signal based on the second control signal. The second calculation control section receives the processed signal, then transmits data related to the first signal to the first calculation control section via the second insulating section, and then shifts to a low power consumption mode.
    Type: Application
    Filed: June 25, 2008
    Publication date: January 22, 2009
    Applicant: Yokogawa Electric Corporation
    Inventors: Yasumi KOIKE, Ikuhiko Ishikawa, Toru Shimura
  • Publication number: 20080282766
    Abstract: An electromagnetic flowmeter for giving a magnetic field to a measurement fluid, detecting an electric signal occurring in the measurement fluid according to the magnetic field, and computing a flow quantity value based on the electric signal includes a zero point measurement section for measuring a zero point of the measurement fluid; a storage section for storing the measured zero point measurement value; a determination section for determining whether or not the difference between the preceding zero point measurement value stored in the storage section and the present zero point measurement value is beyond a predetermined value range; and at least either a transmission section for transmitting the determination result or a display section for displaying the determination result when the determination section determines that the difference is beyond the predetermined value range.
    Type: Application
    Filed: March 10, 2008
    Publication date: November 20, 2008
    Applicant: Yokogawa Electric Corporation
    Inventors: Ikuhiko Ishikawa, Yasumi Koike, Toru Shimura
  • Patent number: 7421907
    Abstract: An electromagnetic flowmeter includes: a detector for detecting a flow rate voltage; a shielded cable having an inner conductor provided around a cable core to which the flow rate voltage is applied from the detector; and a converter for receiving the flow rate voltage via the shielded cable, and performing a signal processing on the received flow rate voltage so as to output the processed flowrate voltage, wherein a preamplifier of the converter includes: an input circuit which is connected between the cable core and a common voltage point and has an input voltage dividing point for dividing the flow rate voltage; a main amplifier circuit which amplifies the flow rate voltage; and a feedback voltage distribution section which receives an output voltage from the main amplifier circuit, and distributes the output voltage as positive feedback voltages to the inner conductor and the input circuit respectively with different ratios.
    Type: Grant
    Filed: March 8, 2007
    Date of Patent: September 9, 2008
    Assignee: Yokogawa Electric Corporation
    Inventor: Ikuhiko Ishikawa
  • Patent number: 7310582
    Abstract: An electromagnetic flow meter of a switching control system in which a DC voltage is applied to an exciting coil via switching elements, a direction of an exciting current flowing through the exciting coil is switched over at a predetermined excitation timing, and the switching elements are turned ON or OFF so as to hold the exciting current to be a predetermined value. The electromagnetic flow meter has first and second detection resistors which are connected in series to ends of the exciting coil via the switching elements, respectively, wherein a midpoint of the first and second detection resistors is grounded to set a voltage of the midpoint as a circuit reference voltage.
    Type: Grant
    Filed: August 10, 2005
    Date of Patent: December 18, 2007
    Assignee: Yokogawa Electric Corporation
    Inventor: Ikuhiko Ishikawa
  • Publication number: 20070283766
    Abstract: An electromagnetic flowmeter includes: a detector for detecting a flow rate voltage; a shielded cable having an inner conductor provided around a cable core to which the flow rate voltage is applied from the detector; and a converter for receiving the flow rate voltage via the shielded cable, and performing a signal processing on the received flow rate voltage so as to output the processed flowrate voltage, wherein a preamplifier of the converter includes: an input circuit which is connected between the cable core and a common voltage point and has an input voltage dividing point for dividing the flow rate voltage; a main amplifier circuit which amplifies the flow rate voltage; and a feedback voltage distribution section which receives an output voltage from the main amplifier circuit, and distributes the output voltage as positive feedback voltages to the inner conductor and the input circuit respectively with different ratios.
    Type: Application
    Filed: March 8, 2007
    Publication date: December 13, 2007
    Applicant: Yokogawa Electric Corporation
    Inventor: Ikuhiko Ishikawa
  • Patent number: 7293468
    Abstract: In order to attain a desired magnetic flux density, a parallel configuration of N divided magnetic circuits is formed, and accommodated on one pair of plate cores as N groups of exciting coils. According to the configuration, the burden of the magnetic coercive force which is driven by one of the magnetic circuits is reduced to 1/N. As a result, the consumption of the excitation power in each of the magnetic circuits can be reduced to (1/N)2. The total of magnetic fluxes which are obtained as a result of parallel driving of the N magnetic circuits are collected onto the single plate core.
    Type: Grant
    Filed: April 5, 2005
    Date of Patent: November 13, 2007
    Assignee: Yokogawa Electric Corporation
    Inventor: Ikuhiko Ishikawa