Patents by Inventor Yohei Shirakawa

Yohei Shirakawa 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).

  • Publication number: 20160210824
    Abstract: A repeater includes two connectors each including electrodes and configured to connect a communication cable through which a differential signal is transmitted, a circuit board on which the two connectors are mounted and which includes a signal transmission section configured to connect corresponding electrodes of the two connectors together, and a signal detection circuit mounted on the circuit board and configured to extract a part of a signal transmitted through the signal transmission section and indicate the presence or absence of information communication based on the extracted signal. The circuit board includes a multi-layer substrate including at least an inner layer in which the signal transmission section is formed, two shield layers configured to interpose the signal transmission section therebetween, and an outer layer outside the shield layer on which the signal detection circuit is mounted.
    Type: Application
    Filed: January 6, 2016
    Publication date: July 21, 2016
    Inventors: Yohei Shirakawa, Koki Hirano, Yoshitake Ageishi, Yuki Haga
  • Publication number: 20160197425
    Abstract: A repeater includes two connectors to each of which a communication cable is connected and a circuit board on which the two connectors are mounted and which includes a signal transmission section configured to connect corresponding ones of electrodes of the two connectors together, and the two connectors are mounted on different surfaces of the circuit board such that the communication cables are inserted in opposite insertion directions.
    Type: Application
    Filed: January 4, 2016
    Publication date: July 7, 2016
    Inventors: Yohei Shirakawa, Koki Hirano, Yoshitake Ageishi
  • Publication number: 20160132416
    Abstract: A communication monitoring system includes a plurality of detecting portions each provided at a connector at an end of a communication cable or at a relay connector to be connected to the connector to branch, extract and output a portion of a signal transmitted through the communication cable, and a monitoring unit configured to monitor an existence of information communication through each of the communication cables provided with the detecting portions based on an output from the plurality of detecting portions.
    Type: Application
    Filed: October 31, 2015
    Publication date: May 12, 2016
    Inventors: Yohei SHIRAKAWA, Koki Hirano, Yoshitake Ageishi
  • Publication number: 20160133110
    Abstract: A cable signal detector for being provided at a connector at an end of a communication cable transmitting differential signals or at a relay connector to be connected to the connector to detect an existence of information communication. The cable signal detector includes an amplifier circuit that branches and extracts a portion of a signal transmitted through the communication cable, amplifies the extracted signal and outputs the amplified signal, and a display portion that display the existence of information communication based on the output of the amplifier circuit. The amplifier circuit is mounted on a detection device formed separately from the connector or the relay connector. The connector or the relay connector is configured to transmit the extracted signal to the detection device.
    Type: Application
    Filed: October 31, 2015
    Publication date: May 12, 2016
    Inventors: Yohei SHIRAKAWA, Koki HIRANO, Yoshitake AGEISHI
  • Publication number: 20160133111
    Abstract: A cable signal detector is configured to detect the presence or absence of information communication in a communication cable including a plurality of signal line pairs for differential signaling. The cable signal detector includes a plurality of detecting portions each of which is configured to partially branch and draw a transmission signal from a different signal line pair, rectify the branched and drawn signal into a direct current, and output that direct current, and a displaying portion configured to display the presence or absence of information communication, based on outputs of the plurality of detecting portions. The outputs of the plurality of detecting portions are connected in series, and the displaying portion is configured to display the presence or absence of information communication, based on an overall output voltage of the plurality of detecting portions connected in series.
    Type: Application
    Filed: October 31, 2015
    Publication date: May 12, 2016
    Inventors: Yohei SHIRAKAWA, Koki Hirano, Yoshitake Ageishi
  • Publication number: 20160104362
    Abstract: A cable signal detector for a connector at an end of a communication cable or for a relay connector connected with the connector includes a rectifier circuit that branches and extracts a portion of signal transmitted through the communication cable, rectifies the extracted signal into a DC signal and outputs the DC signal, a comparator that outputs a predetermined voltage signal if a voltage of the DC signal is not less than a preset threshold voltage, and a light-emitting circuit that emits light when the comparator outputs the predetermined voltage signal.
    Type: Application
    Filed: October 1, 2015
    Publication date: April 14, 2016
    Inventors: Yohei SHIRAKAWA, Koki HIRANO, Yoshitake AGElSHI
  • Publication number: 20160105340
    Abstract: A repeater includes a plurality of input-side connectors and a plurality of output-side connectors corresponding to the input-side connectors that are configured such that communication cables connected to the input-side connectors are connected to other communication cables connected to the output-side connectors, and a detection indicating circuit provided between the input-side connectors and the corresponding output-side connectors. The detection indicating circuit includes a detection circuit branching, extracting and outputting a portion of signal transmitted between the input-side connectors and the corresponding output-side connectors, and an indicating circuit for indicating an establishment of information communication according to an output from the detection circuit.
    Type: Application
    Filed: October 1, 2015
    Publication date: April 14, 2016
    Inventors: Yohei SHIRAKAWA, Koki Hirano, Kanako Suzuki, Takumi Kobayashi, Yoshitake Ageishi
  • Publication number: 20160105214
    Abstract: A crosstalk reduction method includes providing a signal transmission unit including first to eighth main transmission paths, the first and second paths, the third and sixth paths, the fourth and fifth paths and the seventh and eighth paths being respectively paired to transmit differential signals, providing a first coupling transmission path in the signal transmission unit, the first coupling transmission path being adapted to electrically couple the third main transmission path to the fifth and seventh main transmission paths that are located adjacent to the sixth main path, and providing a second coupling transmission path in the signal transmission unit, the second coupling transmission path being adapted to electrically couple the sixth main transmission path to the second and fourth main transmission path that are located adjacent to the third main transmission path.
    Type: Application
    Filed: October 1, 2015
    Publication date: April 14, 2016
    Inventors: Yohei SHIRAKAWA, Koki HIRANO, Yoshitake AGEISHI
  • Publication number: 20160036662
    Abstract: A communication visualization system includes a wireless power-feeding device for transmitting electromagnetic energy in a wireless manner and a communication visualization device for notifying that a LAN cable connected to an information communication apparatus is performing information communication. The communication visualization device includes an antenna part for receiving the electromagnetic energy transmitted from the wireless power-feeding device, a rectifier circuit for rectifying the electromagnetic energy received by the antenna part to generate a DC voltage, an amplifier circuit for amplifying a communication signal transferred to the communication cable at the time of information communication by using the DC voltage generated by the rectifier circuit as operation power, a rectifier circuit for converting the amplified communication signal into a DC voltage, and a light-emitting circuit for emitting light when the DC voltage after conversion is supplied.
    Type: Application
    Filed: August 3, 2015
    Publication date: February 4, 2016
    Inventors: Yohei SHIRAKAWA, Koki HIRANO, Takumi KOBAYASHI, Yoshitake AGEISHI
  • Publication number: 20160035211
    Abstract: A communication visualization device includes a transformer for converting a magnetic field caused from a LAN cable connected to an information communication apparatus into electric energy at time of information communication, an amplifier circuit for amplifying the electric energy output from the transformer, a rectifier circuit for converting an amplified signal amplified by the amplifier circuit into a DC voltage, and a light-emitting circuit for emitting light when the DC voltage obtained by conversion of the rectifier circuit is supplied thereto.
    Type: Application
    Filed: August 3, 2015
    Publication date: February 4, 2016
    Inventors: Yohei SHIRAKAWA, Koki HIRANO, Takumi KOBAYASHI, Yoshitake AGEISHI
  • Publication number: 20150372431
    Abstract: A communication cable connector includes a first connector section to be connected to one end of a communication cable including at least two or more signal lines, a second connector section to be connected to an other end of the communication cable, a first voltage applying circuit mounted to the first connector section to apply a DC voltage between any signal lines of the communication cable, and a first light emitting circuit mounted to the second connector section to emit light when the DC voltage is applied between the any signal lines of the communication cable by the first voltage applying circuit.
    Type: Application
    Filed: June 17, 2015
    Publication date: December 24, 2015
    Inventors: Koki HIRANO, Yohei SHIRAKAWA
  • Publication number: 20150371523
    Abstract: A cable signal detector includes a detection unit that is provided in a connector attached to an end of a communication cable or in a relay connector to be connected to the connector, and branches, extracts and sends a portion of signal transmitted through the cable, and a visualization unit that is provided separately from the connector or the relay connector and includes a light-emitting circuit to emit a light when receiving the signal sent from the detection unit.
    Type: Application
    Filed: June 6, 2015
    Publication date: December 24, 2015
    Inventors: Yohei SHIRAKAWA, Koki HIRANO, Takumi KOBAYASHI, Yoshitake AGEISHI
  • Patent number: 8810332
    Abstract: An electromagnetic coupler includes a first plane, a plurality of conductive patterns formed on the first plane and spaced apart from each other, a second plane parallel to the first plane, a ground pattern formed on the second plane and connected to ground, a first linear conductor formed to have a length shorter than ¼ a wavelength equivalent to a frequency used, the first linear conductor being connected at one end to one conductive pattern of the plural conductive patterns, and fed between an other end of the first linear conductor and the ground pattern, and a plurality of second linear conductors formed to have a length shorter than ¼ the wavelength equivalent to the frequency used, one or more of the second linear conductors being formed for each of the plural conductive patterns, to connect each of the plural conductive patterns and the ground pattern.
    Type: Grant
    Filed: July 19, 2011
    Date of Patent: August 19, 2014
    Assignee: Hitachi Metals, Ltd.
    Inventors: Yohei Shirakawa, Naoto Teraki, Kazuhiro Fujimoto
  • Patent number: 8803629
    Abstract: There is provided an electromagnetic coupler, which includes: a first conductor pattern and at least one second conductor pattern separated from the first conductor pattern, the first conductor pattern and the at least one second conductor pattern being formed in a first conductor layer; a feed pattern connected to a feeding system and a ground pattern separated from the feed pattern, the feed pattern and the ground pattern being composed of a conductor and formed in a second conductor layer; and a plurality of linear conductors electrically connecting the first conductor pattern with the feed pattern and connecting the second conductor pattern with the ground pattern, the plurality of linear conductors being formed between the first conductor layer and the second conductor layer. Furthermore, the first conductor layer and the second conductor layer are parallel to each other.
    Type: Grant
    Filed: April 5, 2011
    Date of Patent: August 12, 2014
    Assignee: Hitachi Metals, Ltd.
    Inventors: Yohei Shirakawa, Kazuhiro Fujimoto, Masamichi Kishi, Naoto Teraki
  • Patent number: 8803754
    Abstract: An antenna includes an antenna element to transmit or receive electromagnetic signals, and a ground conductor to be grounded. The antenna element includes two conductors arranged substantially parallel to each other, a power feed portion provided between one conductor of the two conductors and the ground conductor, and connected to a feed system, a shorting portion for electrically connecting an other conductor of the two conductors and the ground conductor, and a conductor connecting portion for electrically connecting the two conductors together. The distance between the two conductors is not more than 1/100 a wavelength equivalent to a minimum frequency of operating frequencies of the antenna.
    Type: Grant
    Filed: July 19, 2011
    Date of Patent: August 12, 2014
    Assignee: Hitachi Metals, Ltd.
    Inventors: Yohei Shirakawa, Kazuhiro Fujimoto, Masamichi Kishi, Naoto Teraki, Yoshitake Ageishi
  • Patent number: 8742866
    Abstract: An electromagnetic coupler including a conductor pattern formed in a first conductor layer, a feed pattern connected to a feeding system and a ground pattern separated from the feed pattern. The feed pattern and the ground pattern are formed in a second conductor layer parallel to the first conductor layer. A first linear conductor and a plurality of second linear conductors are formed perpendicularly to the first and the second conductor layers. The first linear conductor connects the conductor pattern and the feed pattern. The plurality of second linear conductors connects the conductor pattern and the ground pattern. In addition, the conductor pattern is symmetrical in shape with respect to the connection point between the conductor pattern and the first linear conductor. The plurality of second linear conductors are symmetrical in position with respect to the first linear conductor in a planar view.
    Type: Grant
    Filed: April 5, 2011
    Date of Patent: June 3, 2014
    Assignee: Hitachi Metals, Ltd.
    Inventors: Yohei Shirakawa, Naoto Teraki
  • Patent number: 8700375
    Abstract: There is provided an electromagnetic coupler that communicates signals by using at least one of a longitudinal electrostatic field and a longitudinal induced electric field. The electromagnetic coupler has a ground conductor, a radiation conductor composed of a plurality of rectangular conductors connected in series, and a feeding point formed at one point in the connection of the plurality of rectangular conductors. The plurality of rectangular conductors are connected such that each pair of adjacent rectangular conductors form an angle other than ? radian, and a length from the feeding point to either end of the radiation conductor is an integral multiple of ?/4 in electrical length with respect to a wavelength ? of a central frequency of a frequency band of interest of the electromagnetic coupler.
    Type: Grant
    Filed: March 25, 2011
    Date of Patent: April 15, 2014
    Assignee: Hitachi Metals, Ltd.
    Inventors: Yohei Shirakawa, Keisuke Fukuchi
  • Patent number: 8633783
    Abstract: An electromagnetic coupler has a first conductor pattern and a second conductor pattern separated from the first conductor pattern that are formed in a first plane, a feeding pattern made of a conductor and being connected to a feeing system and a ground made of a conductor and being separated from the feeding pattern that are formed in a second plane, and linear conductors electrically connecting between the first conductor pattern and the feeding pattern, and between the second conductor pattern and the ground, respectively.
    Type: Grant
    Filed: October 8, 2010
    Date of Patent: January 21, 2014
    Assignees: Hitachi Cable Fine-Tech, Ltd., Hitachi Cable, Ltd.
    Inventors: Yohei Shirakawa, Keisuke Fukuchi, Haruyuki Watanabe
  • Publication number: 20120249390
    Abstract: There is provided an antenna comprising: a ground conductor; and an antenna element portion for sending and receiving electromagnetic wave signals, the antenna element portion comprising: a coaxial cable including a center conductor and an outer conductor; a feeding point connected to a feeding system and disposed between the ground conductor and a first end of one of the center and outer conductors; a short-circuit portion electrically connecting the ground conductor and a first end of the other one of the center and outer conductors; and a conductor connection portion electrically connecting second ends of the center and outer conductors each other. In addition, an overall length of the coaxial cable is not more than ½ of a wavelength corresponding to the minimum series resonance frequency; and a distance between the center and outer conductors is not more than 1/100 of a wavelength corresponding to the minimum operation frequency.
    Type: Application
    Filed: March 28, 2012
    Publication date: October 4, 2012
    Inventors: Yohei Shirakawa, Kazuhiro Fujimoto, Masamichi Kishi, Naoto Teraki, Yoshitake Ageishi
  • Publication number: 20120176208
    Abstract: An electromagnetic coupler includes a first plane, a plurality of conductive patterns formed on the first plane and spaced apart from each other, a second plane parallel to the first plane, a ground pattern formed on the second plane and connected to ground, a first linear conductor formed to have a length shorter than ¼ a wavelength equivalent to a frequency used, the first linear conductor being connected at one end to one conductive pattern of the plural conductive patterns, and fed between an other end of the first linear conductor and the ground pattern, and a plurality of second linear conductors formed to have a length shorter than ¼ the wavelength equivalent to the frequency used, one or more of the second linear conductors being formed for each of the plural conductive patterns, to connect each of the plural conductive patterns and the ground pattern.
    Type: Application
    Filed: July 19, 2011
    Publication date: July 12, 2012
    Applicant: Hitachi Cable Fine-Tech, Ltd.
    Inventors: Yohei Shirakawa, Naoto Teraki, Kazuhiro Fujimoto