Patents by Inventor Kohji TOKUYAMA

Kohji TOKUYAMA 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: 11427013
    Abstract: A liquid discharge apparatus includes a liquid discharge head to discharge liquid, a liquid circulation path including the liquid discharge head, an exhaust path connected to the liquid circulation path on a downstream side of the liquid discharge head in a circulation direction of the liquid, and circuitry. The liquid circulation path circulates the liquid via the liquid discharge head. The circuitry opens and closes between the liquid circulation path and the exhaust path to exhaust bubbles in the liquid circulation path to an outside of the liquid circulation path through the exhaust path when the liquid is circulated in the liquid circulation path.
    Type: Grant
    Filed: January 12, 2021
    Date of Patent: August 30, 2022
    Assignee: Ricoh Company, Ltd.
    Inventor: Kohji Tokuyama
  • Publication number: 20210260889
    Abstract: A liquid discharge apparatus includes a liquid discharge head to discharge liquid, a liquid circulation path including the liquid discharge head, an exhaust path connected to the liquid circulation path on a downstream side of the liquid discharge head in a circulation direction of the liquid, and circuitry. The liquid circulation path circulates the liquid via the liquid discharge head. The circuitry opens and closes between the liquid circulation path and the exhaust path to exhaust bubbles in the liquid circulation path to an outside of the liquid circulation path through the exhaust path when the liquid is circulated in the liquid circulation path.
    Type: Application
    Filed: January 12, 2021
    Publication date: August 26, 2021
    Applicant: Ricoh Company, Ltd.
    Inventor: Kohji Tokuyama
  • Publication number: 20170153591
    Abstract: An image forming apparatus including an image forming unit configured to form an image on a recording medium; an edge detecting unit configured to detect edge positions at a plurality of portions along each side of the recording medium being conveyed; a shape detecting unit configured to detect a shape of the recording medium, based on an edge detection result obtained by the edge detecting unit; and an image correcting unit configured to correct the image to be formed on the recording medium, based on a change in the shape of the recording medium before and after image forming, the change being detected by the shape detecting unit.
    Type: Application
    Filed: February 14, 2017
    Publication date: June 1, 2017
    Applicant: Ricoh Company, Ltd.
    Inventors: Makoto NAKURA, Yuji KARIKUSA, Kohji TOKUYAMA, Tohru MATSUMOTO, Daisuke ARAI
  • Patent number: 9347881
    Abstract: A device for detecting a state of a liquid droplet discharged from each of nozzles placed in one or more rows, includes a light emitting element to emit a light beam to the liquid droplet from a nozzle in question, and a pair of light receiving elements disposed on both sides of a beam diameter of the light beam via an optical axis to receive scattered light occurring from the liquid droplet for detecting a state of the discharged liquid droplet on the basis of the scattered light. Either of the pair of the light receiving elements is selected for receiving the scattered light from the liquid droplet discharged from the nozzle according to a positional relation between the nozzle and the pair of light receiving elements.
    Type: Grant
    Filed: December 19, 2014
    Date of Patent: May 24, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroshi Andoh, Hideharu Miki, Genichiro Kawamichi, Shigeru Morinaga, Kohji Tokuyama, Toshihide Inaba, Mitsuyuki Karasawa, Takeo Shirato
  • Publication number: 20150378297
    Abstract: An image forming apparatus including an image forming unit configured to form an image on a recording medium; an edge detecting unit configured to detect edge positions at a plurality of portions along each side of the recording medium being conveyed; a shape detecting unit configured to detect a shape of the recording medium, based on an edge detection result obtained by the edge detecting unit; and an image correcting unit configured to correct the image to be formed on the recording medium, based on a change in the shape of the recording medium before and after image forming, the change being detected by the shape detecting unit.
    Type: Application
    Filed: June 25, 2015
    Publication date: December 31, 2015
    Applicant: RICOH COMPANY, LTD.
    Inventors: Makoto NAKURA, Yuji KARIKUSA, Kohji TOKUYAMA, Tohru MATSUMOTO, Daisuke ARAI
  • Publication number: 20150177136
    Abstract: A device for detecting a state of a liquid droplet discharged from each of nozzles placed in one or more rows, includes a light emitting element to emit a light beam to the liquid droplet from a nozzle in question, and a pair of light receiving elements disposed on both sides of a beam diameter of the light beam via an optical axis to receive scattered light occurring from the liquid droplet for detecting a state of the discharged liquid droplet on the basis of the scattered light. Either of the pair of the light receiving elements is selected for receiving the scattered light from the liquid droplet discharged from the nozzle according to a positional relation between the nozzle and the pair of light receiving elements.
    Type: Application
    Filed: December 19, 2014
    Publication date: June 25, 2015
    Applicant: RICOH COMPANY, LTD.
    Inventors: Hiroshi Andoh, Hideharu Miki, Genichiro Kawamichi, Shigeru Morinaga, Kohji Tokuyama, Toshihide Inaba, Mitsuyuki Karasawa, Takeo Shirato
  • Publication number: 20150009252
    Abstract: A liquid drop ejection state detection device includes a plurality of nozzle sequences configured to have a plurality of nozzles, a light-emitting element configured to emit a light beam incident on a liquid drop from each nozzle of each nozzle sequence, a light-receiving element provided at a position outside a beam diameter of the light beam and configured to receive scattered light from the liquid drop and detect an ejection state of the liquid drop based on an amount of the scattered light, a light-emitting element movement part configured to move the light-emitting element in a direction intersecting with a light axis of the light beam, and an adjustment part configured to adjust an amount of light of the light beam emitted from the light-emitting element.
    Type: Application
    Filed: June 27, 2014
    Publication date: January 8, 2015
    Applicant: Ricoh Company, Ltd.
    Inventors: Hiroshi Andoh, Hideharu Miki, Genichiro Kawamichi, Kohji Tokuyama, Shigeru Morinaga
  • Patent number: 8611791
    Abstract: Disclosed is a roller replacement auxiliary tool of a fixing unit for extracting at least one of a heating roller and a pressure roller from a replacement opening part formed in a frame of the fixing unit in a shaft direction so as to be replaced. The heating roller has a heater lamp provided therein, and the pressure roller is capable of being brought into press-contact with the heating roller. The roller replacement auxiliary tool includes a protection unit that protects the roller when the roller is replaced.
    Type: Grant
    Filed: January 24, 2011
    Date of Patent: December 17, 2013
    Assignee: Ricoh Company, Ltd.
    Inventors: Kohji Tokuyama, Yutaka Nagasawa, Genichiro Kawamichi
  • Publication number: 20110188883
    Abstract: Disclosed is a roller replacement auxiliary tool of a fixing unit for extracting at least one of a heating roller and a pressure roller from a replacement opening part formed in a frame of the fixing unit in a shaft direction so as to be replaced. The heating roller has a heater lamp provided therein, and the pressure roller is capable of being brought into press-contact with the heating roller. The roller replacement auxiliary tool includes a protection unit that protects the roller when the roller is replaced.
    Type: Application
    Filed: January 24, 2011
    Publication date: August 4, 2011
    Inventors: Kohji TOKUYAMA, Yutaka Nagasawa, Genichiro Kawamichi