Patents by Inventor Kohhei Yamaguchi

Kohhei Yamaguchi 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: 20210197557
    Abstract: A liquid ejecting apparatus includes a plurality of ejection heads, each including a nozzle array in which a plurality of nozzles, each configured to eject a droplet, are arranged in an array; and an ejection receiver configured to receive the droplet from the plurality of ejection heads. A conveying direction in which an ejection target medium is conveyed and an arrangement direction in which the nozzle array is arranged are parallel to each other, and at a predetermined timing, at least one ejection head among the plurality of ejection heads moves to a position facing the ejection target medium and ejects the droplet toward the ejection target medium, and, simultaneously, a remaining ejection head among the plurality of ejection heads other than the at least one ejection head moves to be withdrawn from the position facing the ejection target medium and ejects the droplet toward the ejection receiver.
    Type: Application
    Filed: December 23, 2020
    Publication date: July 1, 2021
    Applicant: Ricoh Company, Ltd.
    Inventor: Kohhei YAMAGUCHI
  • Publication number: 20210162737
    Abstract: A liquid discharge apparatus includes a discharge head having a nozzle row, a conveyor is configured to convey a discharge target medium, a head mover configured to move the discharge head in an orthogonal direction, a head rotator configured to rotate the discharge head, and circuitry configured to perform a position setting operation to cause the head mover to move the discharge head to a position in the orthogonal direction, a discharging operation to cause the discharge head to discharge a liquid at the position, a medium conveying operation to cause the conveyor to convey the discharge target medium, and a changing operation to cause the head mover to change the position of the discharge head, and cause the head rotator to rotate the discharge head based on a length of droplets of the liquid landed on the discharge target medium by the above-described operations.
    Type: Application
    Filed: November 25, 2020
    Publication date: June 3, 2021
    Applicant: Ricoh Company, Ltd.
    Inventors: SHOGO MIURA, KOHHEI YAMAGUCHI, KOHTAROH IKEGAMI
  • Patent number: 10919293
    Abstract: A liquid discharge apparatus includes a liquid discharge head, a scanning device, a conveyance device, a reading device, control circuitry, and a detecting device. The liquid discharge head is configured to discharge liquid to a target object. The scanning device is configured to move the liquid discharge head in a main scanning direction. The conveyance device is configured to convey the target object in a direction perpendicular to the main scanning direction. The reading device is disposed at a predetermined position with respect to the liquid discharge head. The control circuitry is configured to change a detection pattern image for detecting a defective nozzle, in accordance with a feed amount of the target object in the sub-scanning direction. The detecting device is configured to identify a nozzle corresponding to a defective portion of the detection pattern image read by the reading device.
    Type: Grant
    Filed: July 30, 2019
    Date of Patent: February 16, 2021
    Assignee: RICOH COMPANY, LTD.
    Inventors: Kohhei Yamaguchi, Nobuyuki Satoh, Suguru Yokozawa
  • Publication number: 20200039211
    Abstract: A liquid discharge apparatus includes a liquid discharge head, a scanning device, a conveyance device, a reading device, control circuitry, and a detecting device. The liquid discharge head is configured to discharge liquid to a target object. The scanning device is configured to move the liquid discharge head in a main scanning direction. The conveyance device is configured to convey the target object in a direction perpendicular to the main scanning direction. The reading device is disposed at a predetermined position with respect to the liquid discharge head. The control circuitry is configured to change a detection pattern image for detecting a defective nozzle, in accordance with a feed amount of the target object in the sub-scanning direction. The detecting device is configured to identify a nozzle corresponding to a defective portion of the detection pattern image read by the reading device.
    Type: Application
    Filed: July 30, 2019
    Publication date: February 6, 2020
    Applicant: Ricoh Company, Ltd.
    Inventors: Kohhei YAMAGUCHI, Nobuyuki Satoh, Suguru Yokozawa
  • Patent number: 10523696
    Abstract: Proposed are a log analyzing system and a log analyzing method capable of more effectively defending a control system from unauthorized access. The log analyzing system which analyzes a communication log of a control device comprises a network device which receives a communication packet corresponding to the communication log from a network, and a monitoring device which monitors communication to the network device, wherein the monitoring device obtains a difference between a communication pattern of the communication packet and a stable pattern, which is a pattern of a communication in a state of no unauthorized access, restores the communication packet based on the difference, and notifies the restored communication packet.
    Type: Grant
    Filed: October 27, 2017
    Date of Patent: December 31, 2019
    Assignee: Hitachi, Ltd.
    Inventors: Hiroki Uchiyama, Akifumi Yato, Satoshi Ohkubo, Kohhei Yamaguchi
  • Patent number: 10341294
    Abstract: A detection apparatus 30 stores a determination list (A1601) for determining whether there is unauthorized communication, receives a communication packet (A1501) flowing in a control system, determines whether a valid data pattern in the determination list (A1601) and a data pattern relating to the communication packet (A1501) match each other. When the valid data pattern in the determination list (A1601) and the data pattern relating to the communication packet do not match each other, the detection apparatus 30 calculates a similarity degree between the valid data pattern in the determination list and the data pattern relating to the communication packet, and determines whether the similarity degree satisfies a predetermined condition. When the similarity degree is determined not to satisfy the predetermined condition, the detection apparatus 30 determines that the communication packet (A1501) is an unauthorized communication packet.
    Type: Grant
    Filed: May 11, 2017
    Date of Patent: July 2, 2019
    Assignee: HITACHI, LTD.
    Inventors: Shugo Mikami, Hiroki Uchiyama, Satoshi Ohkubo, Kohhei Yamaguchi
  • Patent number: 10082818
    Abstract: An electronic circuit includes a first consumption part, at least one second consumption part, and a current mirror circuit. The first consumption part passes a current to consume electricity when a voltage exceeding a first voltage is applied. At least one second consumption part is disposed in parallel with the first consumption part and passes a current to consume electricity. The current mirror circuit passes, to the second consumption part, a current corresponding to a current that flows through the first consumption part.
    Type: Grant
    Filed: November 22, 2016
    Date of Patent: September 25, 2018
    Assignee: Ricoh Company, LTD.
    Inventors: Masashi Kasamai, Kohhei Yamaguchi, Yoshihiro Takahashi
  • Publication number: 20180124083
    Abstract: Proposed are a log analyzing system and a log analyzing method capable of more effectively defending a control system from unauthorized access. The log analyzing system which analyzes a communication log of a control device comprises a network device which receives a communication packet corresponding to the communication log from a network, and a monitoring device which monitors communication to the network device, wherein the monitoring device obtains a difference between a communication pattern of the communication packet and a stable pattern, which is a pattern of a communication in a state of no unauthorized access, restores the communication packet based on the difference, and notifies the restored communication packet.
    Type: Application
    Filed: October 27, 2017
    Publication date: May 3, 2018
    Inventors: Hiroki UCHIYAMA, Akifumi YATO, Satoshi OHKUBO, Kohhei YAMAGUCHI
  • Publication number: 20170331787
    Abstract: A detection apparatus 30 stores a determination list (A1601) for determining whether there is unauthorized communication, receives a communication packet (A1501) flowing in a control system, determines whether a valid data pattern in the determination list (A1601) and a data pattern relating to the communication packet (A1501) match each other. When the valid data pattern in the determination list (A1601) and the data pattern relating to the communication packet do not match each other, the detection apparatus 30 calculates a similarity degree between the valid data pattern in the determination list and the data pattern relating to the communication packet, and determines whether the similarity degree satisfies a predetermined condition. When the similarity degree is determined not to satisfy the predetermined condition, the detection apparatus 30 determines that the communication packet (A1501) is an unauthorized communication packet.
    Type: Application
    Filed: May 11, 2017
    Publication date: November 16, 2017
    Applicant: HITACHI, LTD.
    Inventors: Shugo MIKAMI, Hiroki UCHIYAMA, Satoshi OHKUBO, Kohhei YAMAGUCHI
  • Publication number: 20170153658
    Abstract: An electronic circuit includes a first consumption part, at least one second consumption part, and a current mirror circuit. The first consumption part passes a current to consume electricity when a voltage exceeding a first voltage is applied. At least one second consumption part is disposed in parallel with the first consumption part and passes a current to consume electricity. The current mirror circuit passes, to the second consumption part, a current corresponding to a current that flows through the first consumption part.
    Type: Application
    Filed: November 22, 2016
    Publication date: June 1, 2017
    Applicant: Ricoh Company, Ltd.
    Inventors: Masashi KASAMAI, Kohhei Yamaguchi, Yoshihiro Takahashi
  • Patent number: 9436121
    Abstract: There is provided a driving apparatus comprising: a driving unit configured to rotate a driving shaft; a speed setting unit for setting a rotational speed of the driving shaft; a driving shaft joint connected with the driving shaft to rotate with the driving shaft for transmitting driving-force to a driven apparatus, the driving shaft joint being fitted into a driven shaft joint connected with the driven apparatus that is made detachable; a rotational position detection unit configured to detect a predetermined rotational position of the driving shaft joint; and a driving control unit configured to control the driving unit; wherein upon the driven apparatus being detached, the driving control unit controls the driving unit to stop the rotating driving shaft based on a detection result of the rotational position detection unit after the speed setting unit sets the rotational speed of the driving shaft to be a first rotational speed.
    Type: Grant
    Filed: October 21, 2015
    Date of Patent: September 6, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Kohhei Yamaguchi, Hiroyuki Iwasaki, Yusuke Ishizaki
  • Publication number: 20160124342
    Abstract: There is provided a driving apparatus comprising: a driving unit configured to rotate a driving shaft; a speed setting unit for setting a rotational speed of the driving shaft; a driving shaft joint connected with the driving shaft to rotate with the driving shaft for transmitting driving-force to a driven apparatus, the driving shaft joint being fitted into a driven shaft joint connected with the driven apparatus that is made detachable; a rotational position detection unit configured to detect a predetermined rotational position of the driving shaft joint; and a driving control unit configured to control the driving unit; wherein upon the driven apparatus being detached, the driving control unit controls the driving unit to stop the rotating driving shaft based on a detection result of the rotational position detection unit after the speed setting unit sets the rotational speed of the driving shaft to be a first rotational speed.
    Type: Application
    Filed: October 21, 2015
    Publication date: May 5, 2016
    Applicant: RICOH COMPANY, LTD.
    Inventors: Kohhei YAMAGUCHI, Hiroyuki IWASAKI, Yusuke ISHIZAKI
  • Publication number: 20130241293
    Abstract: A power control system includes an electronic apparatus; and a power transmission apparatus configured to send power to the electronic apparatus. The power transmission apparatus includes a power generation unit configured to generate the power; a first communication unit configured to communicate with the electronic apparatus; and a power transmission unit configured to send the generated power to the electronic apparatus in response to a request from the electronic apparatus. The electronic apparatus includes a second communication unit configured to send, to the power transmission apparatus, a request for starting or stopping supplying the power; a power receiving unit configured to receive the power from the power transmission apparatus; and a control unit configured to reduce the power supplied to the second communication unit in a power saving mode.
    Type: Application
    Filed: March 1, 2013
    Publication date: September 19, 2013
    Inventor: Kohhei YAMAGUCHI
  • Patent number: 7873295
    Abstract: An energy-saving control unit detects a supply of power to an image forming apparatus and performs an energy saving control of an external controller. A switching unit switches a start and a stop of supply of power to an onboard circuit of the external controller. Upon detecting the supply of power to the image forming apparatus, the energy-saving control unit sends a power control signal for instructing a start of the supply of power to the onboard circuit to the switching unit. Upon receiving the power control signal, the switching unit switches to the start of the supply of power to the onboard circuit.
    Type: Grant
    Filed: July 18, 2008
    Date of Patent: January 18, 2011
    Assignee: Ricoh Company, Ltd.
    Inventor: Kohhei Yamaguchi
  • Publication number: 20090022508
    Abstract: An energy-saving control unit detects a supply of power to an image forming apparatus and performs an energy saving control of an external controller. A switching unit switches a start and a stop of supply of power to an onboard circuit of the external controller. Upon detecting the supply of power to the image forming apparatus, the energy-saving control unit sends a power control signal for instructing a start of the supply of power to the onboard circuit to the switching unit. Upon receiving the power control signal, the switching unit switches to the start of the supply of power to the onboard circuit.
    Type: Application
    Filed: July 18, 2008
    Publication date: January 22, 2009
    Inventor: Kohhei YAMAGUCHI