Patents by Inventor Yoshiki Yamaguchi

Yoshiki 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).

  • Patent number: 9696668
    Abstract: A fixing device includes a fixing member; a heater to heat the fixing member; a nip forming member to contact the fixing member; and a pressure member, disposed opposite the nip forming member to press against the fixing member to form a fixing nip portion together with the nip forming member. The fixing device applies heat and pressure to fix an image transferred to a recording sheet when the recording sheet passes through the fixing nip. The nip forming member includes a first and second planar portions disposed at an upstream end and a downstream end, respectively, of the fixing nip portion, and the first planar portion and the second planar portion are continuous with a curved portion of the nip forming member. A guide member guides the recording sheet to bend in a direction opposite a back curl of the recording sheet generated in the fixing nip portion.
    Type: Grant
    Filed: March 8, 2016
    Date of Patent: July 4, 2017
    Assignee: RICOH COMPANY, LTD.
    Inventors: Yoshiki Yamaguchi, Yoshio Hattori, Ryuuichi Mimbu, Haruyuki Honda, Toshihiko Shimokawa
  • Publication number: 20170102652
    Abstract: According to an embodiments, a fixing device includes: an endless fixing member; a heating unit that is provided inside an inner peripheral surface of the fixing member; and a nip forming unit that comes into press-contact with a rotationally driven pressing member with the fixing member interposed therebetween to form a nip. The nip forming unit has a shape in which a center of a contact surface protrudes toward the pressing member compared to both ends. The nip forming unit has a protruding amount at a center toward the pressing member compared to both ends of the nip forming unit in no-load state is set to be less than a bent amount of the nip forming unit when the nip forming unit comes into press-contact with the pressing member with the fixing member interposed therebetween.
    Type: Application
    Filed: December 20, 2016
    Publication date: April 13, 2017
    Applicant: Ricoh Company, Ltd.
    Inventors: Takahiro IMADA, Masaaki Yoshikawa, Kenji Ishii, Hiroshi Yoshinaga, Yuji Arai, Naoki Iwaya, Tetsuo Tokuda, Hiromasa Takagi, Yoshiki Yamaguchi, Ippei Fujimoto, Takuya Seshita, Yutaka Ikebuchi, Arinobu Yoshiura, Toshihiko Shimokawa, Hajime Gotoh
  • Patent number: 9599941
    Abstract: A fixing device includes a fixing rotator rotatable in a predetermined direction of rotation and including a heated face and a heater including a contact face contacting the heated face of the fixing rotator. The contact face has a Vickers hardness not greater than about 600 Hv.
    Type: Grant
    Filed: December 24, 2014
    Date of Patent: March 21, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Yoshiki Yamaguchi, Kazuhito Kishi, Yasunori Ishigaya, Ippei Fujimoto, Keisuke Kawabata, Haruyuki Honda
  • Patent number: 9581945
    Abstract: A fixing exit guide plate for use in a fixing device, which supports the conveyance of a paper while being curved in a direction opposite to a curl direction of the paper in a paper conveyance path downstream of conveyance support rollers, includes a conveyance downstream portion having a paper conveyance plane and a conveyance upstream portion having a paper conveyance plane, wherein the fixing exit guide plate is retracted in a paper jam process to move such that the paper conveyance plane of the conveyance downstream portion rotates about a rotation axis of the conveyance support driving roller to be substantially parallel to the paper conveyance plane of a conveyance upstream portion.
    Type: Grant
    Filed: February 29, 2016
    Date of Patent: February 28, 2017
    Assignee: RICOH COMPANY, LTD.
    Inventors: Haruyuki Honda, Ryuuichi Mimbu, Yoshio Hattori, Yoshiki Yamaguchi, Toshihiko Shimokawa
  • Patent number: 9557692
    Abstract: A fixing device may include an endless fixing member; a heating unit that is provided inside an inner peripheral surface of the fixing member; and a nip forming unit that comes into press-contact with a rotationally driven pressing member with the fixing member interposed therebetween to form a nip. The nip forming unit has a shape in which a center of a contact surface protrudes toward the pressing member compared to both ends. The nip forming unit has a protruding amount at a center toward the pressing member compared to both ends of the nip forming unit in no-load state is set to be less than a bent amount of the nip forming unit when the nip forming unit comes into press-contact with the pressing member with the fixing member interposed therebetween.
    Type: Grant
    Filed: September 11, 2015
    Date of Patent: January 31, 2017
    Assignee: Ricoh Company, Limited
    Inventors: Takahiro Imada, Masaaki Yoshikawa, Kenji Ishii, Hiroshi Yoshinaga, Yuji Arai, Naoki Iwaya, Tetsuo Tokuda, Hiromasa Takagi, Yoshiki Yamaguchi, Ippei Fujimoto, Takuya Seshita, Yutaka Ikebuchi, Arinobu Yoshiura, Toshihiko Shimokawa, Hajime Gotoh
  • Patent number: 9529308
    Abstract: An image forming apparatus includes a fixing rotator and an opposed rotator pressed against the fixing rotator to form a fixing nip therebetween, through which a recording medium bearing a toner image is conveyed. A heater heats the fixing rotator. A temperature sensor contacts the opposed rotator to detect a temperature of the opposed rotator. A conveyor conveys the recording medium to the fixing nip. A driver drives the conveyor. A controller, operatively connected to the temperature sensor and the driver, controls the driver to drive the conveyor to convey the recording medium to the fixing nip based on the temperature of the opposed rotator detected by the temperature sensor. The controller causes the driver to be ready to drive the conveyor when a change in the detected temperature of the opposed rotator per unit time reaches a predetermined threshold.
    Type: Grant
    Filed: October 23, 2015
    Date of Patent: December 27, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Yutaka Ikebuchi, Yoshio Hattori, Ryuuichi Mimbu, Yasunori Ishigaya, Yoshiki Yamaguchi, Kazuya Saito, Toshihiko Shimokawa, Keitaro Shoji
  • Patent number: 9518736
    Abstract: A water-containing solid fuel drying apparatus that can efficiently dry with low energy consumption by effectively utilizing sensible heat and latent heat of a heating medium for drying, etc. is provided.
    Type: Grant
    Filed: May 25, 2010
    Date of Patent: December 13, 2016
    Assignees: MITSUBISHI HEAVY INDUSTRIES, LTD., THE UNIVERSITY OF TOKYO
    Inventors: Katsuhiko Yokohama, Kenichiro Kosaka, Keigo Matsumoto, Noboru Kawamoto, Yoshiki Yamaguchi, Masaaki Kinoshita, Koji Ohura, Atsushi Tsutsumi, Shozo Kaneko, Kazuhiro Mochizuki, Chihiro Fushimi, Yasuki Kansha
  • Patent number: 9501011
    Abstract: A fixing device to fix a toner image on a sheet includes a first rotary member that rotates in a predetermined direction and a second rotary member that contacts an outer circumferential surface of the first rotary member. A stationary member is fixed inside the first rotary member to press the first and second rotary members together to form a nip portion between the rotary members. A reinforcement member is fixedly provided inside the first rotary member and pressed against the stationary member. The fixing device includes heat source to heat the first rotary member and a reflector to reflect heater light emitted from the heat source toward the first rotary member.
    Type: Grant
    Filed: August 17, 2015
    Date of Patent: November 22, 2016
    Assignee: RICOH COMPANY, LTD.
    Inventors: Ippei Fujimoto, Akira Shinshi, Naoki Iwaya, Yoshiki Yamaguchi, Shuntaroh Tamaki, Hiroshi Yoshinaga, Yutaka Ikebuchi, Toshihiko Shimokawa, Kenichi Hasegawa
  • Patent number: 9501006
    Abstract: A fixing device includes a heater that heats a fixing rotator and includes a first heating portion and a second heating portion substantially aligned with the first heating portion in an axial direction of the fixing rotator. A multi-view thermopile array detects a temperature of an outer circumferential surface of the fixing rotator at a plurality of spots thereon. A heater controller controls the first heating portion and the second heating portion individually based on the temperature of the fixing rotator detected at the plurality of spots thereon. A recording medium conveyance controller determines whether or not to convey the recording medium to the fixing nip based on an increased temperature detected at at least one of the plurality of spots on the fixing rotator.
    Type: Grant
    Filed: July 22, 2015
    Date of Patent: November 22, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Toshihiko Shimokawa, Ryuuichi Mimbu, Kazuya Saito, Haruyuki Honda, Yoshiki Yamaguchi, Yasunori Ishigaya, Yoshio Hattori
  • Patent number: 9494901
    Abstract: A fixing device includes a nip formation pad pressing against a pressure rotator via a fixing rotator to form a fixing nip between the fixing rotator and the pressure rotator. The nip formation pad includes a base and a first thermal conductor sandwiched between the base and the fixing rotator at the fixing nip and having a first thermal conductivity greater than a basic thermal conductivity of the base. A first heater and a second heater are disposed opposite an inner circumferential surface of the fixing rotator to heat the fixing rotator. A rotatable light shield moves to a shield position where the light shield is interposed between the second heater and the fixing rotator to shield the fixing rotator from the second heater. The second heater is disposed at a location where the light shield screens the second heater more readily than the first heater.
    Type: Grant
    Filed: November 25, 2015
    Date of Patent: November 15, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Kazuya Saito, Ryuuichi Mimbu, Toshihiko Shimokawa, Haruyuki Honda, Yoshiki Yamaguchi, Yasunori Ishigaya, Keitaro Shoji, Yutaka Ikebuchi, Yoshio Hattori
  • Publication number: 20160274509
    Abstract: A fixing device has a flexible endless fixing member; a heater to heat the fixing member; a nip forming member to contact the fixing member directly or via a slide member; a pressure member, rotatably disposed opposite the fixing member and the nip forming member; and a back curl correction structure that includes a drive roller disposed on a side where a back curl appears in the recording sheet; a driven roller disposed opposite the drive roller; an auxiliary nip portion to feed the recording sheet; a guide member to guide the recording sheet fed out from the auxiliary nip portion to bend in a direction opposite a curled direction of the back curl of the recording sheet. A driving connection between the drive roller and the pressure member is performed by a connection between a drive roller side connection gear and a pressure member side connection gear.
    Type: Application
    Filed: March 18, 2016
    Publication date: September 22, 2016
    Applicant: Ricoh Company, Ltd.
    Inventors: Haruyuki Honda, Ryuuichi MIMBU, Yoshio HATTORI, Yoshiki YAMAGUCHI, Toshihiko SHIMOKAWA
  • Publication number: 20160274513
    Abstract: A fixing device includes a fixing member; a heater to heat the fixing member; a nip forming member to contact the fixing member; and a pressure member, disposed opposite the nip forming member to press against the fixing member to form a fixing nip portion together with the nip forming member. The fixing device applies heat and pressure to fix an image transferred to a recording sheet when the recording sheet passes through the fixing nip. The nip forming member includes a first and second planar portions disposed at an upstream end and a downstream end, respectively, of the fixing nip portion, and the first planar portion and the second planar portion are continuous with a curved portion of the nip forming member. A guide member guides the recording sheet to bend in a direction opposite a back curl of the recording sheet generated in the fixing nip portion.
    Type: Application
    Filed: March 8, 2016
    Publication date: September 22, 2016
    Applicant: Ricoh Company, Ltd.
    Inventors: Yoshiki YAMAGUCHI, Yoshio HATTORI, Ryuuichi MIMBU, Haruyuki HONDA, Toshihiko SHIMOKAWA
  • Publication number: 20160274523
    Abstract: An image forming apparatus includes an image forming device to transfer an image to a recording sheet; a fixing device to feed the recording sheet and fix the image onto the recording sheet; a branching device to switch between an ejection path to eject the recording sheet fed downstream of the fixing device, to outside the apparatus, and a reversing path for duplex printing; and a back curl correction structure disposed in a sheet feeding path between the fixing device and the branching device. The back curl correction structure includes a drive roller; a driven roller; an auxiliary nip portion; a guide member; and a guide moving device to move the guide member to a first position and a second position depending on the condition of the recording sheet.
    Type: Application
    Filed: March 8, 2016
    Publication date: September 22, 2016
    Applicant: Ricoh Company, Ltd.
    Inventors: Ryuuichi MIMBU, Yoshio Hattori, Haruyuki Honda, Toshihiko Shimokawa, Yoshiki Yamaguchi
  • Publication number: 20160274508
    Abstract: A fixing exit guide plate for use in a fixing device, which supports the conveyance of a paper with being curved in a direction opposite to a curl direction of the paper in a paper conveyance path in a downstream of a conveyance support rollers, includes a conveyance downstream portion having a paper conveyance plane and a conveyance upstream portion having a paper conveyance plane, wherein the fixing exit guide plate is retracted in a paper jam process to move such that the paper conveyance plane of the conveyance downstream portion rotates about a rotation axis of the conveyance support driving roller to be substantially parallel to the paper conveyance plane of the conveyance upstream portion.
    Type: Application
    Filed: February 29, 2016
    Publication date: September 22, 2016
    Applicant: Ricoh Company, Ltd.
    Inventors: Haruyuki HONDA, Ryuuichi MIMBU, Yoshio HATTORI, Yoshiki YAMAGUCHI, Toshihiko SHIMOKAWA
  • Publication number: 20160274516
    Abstract: A fixing device includes an endless fixing belt; a pressure roller to contact the fixing belt; a nip forming member to press the pressure roller from the fixing belt; a nip portion formed between the fixing belt and the pressure roller; a heater to heat the fixing belt to fuse and fix toner onto a recording sheet in the nip portion; an auxiliary driven roller; an auxiliary drive roller to drive the driven roller; an auxiliary nip portion, formed between an outer circumferential surface of the auxiliary driven roller and an outer circumferential surface of the auxiliary drive roller, to nip the recording sheet after toner fixation conveyed from the nip portion; and an outlet guide member, disposed downstream of the auxiliary nip portion, to guide the recording sheet after toner fixation conveyed from the auxiliary nip portion, with the toner-fixed recording sheet surface bent in a concave shape.
    Type: Application
    Filed: March 15, 2016
    Publication date: September 22, 2016
    Applicant: Ricoh Company, Ltd.
    Inventors: Yoshiki YAMAGUCHI, Yoshio HATTORI, Haruyuki HONDA, Ryuuichi MIMBU, Toshihiko SHIMOKAWA, Yutaka IKEBUCHI, Yasunori ISHIGAYA, Kazuya SAITO, Keitaro SHOJI, Ryohei MATSUDA
  • Publication number: 20160225215
    Abstract: A paper sheet authentication apparatus determines the type of the paper sheet by using a characteristic other than a fluorescent light characteristic, sequentially emits excitation lights of different wavelengths on the paper sheet, measures an intensity of light per wavelength within a predetermined range emitted by a fluorescent material applied to the paper sheet, and acquires fluorescent light characteristic data as the result. The paper sheet authentication apparatus performs the authentication of the paper sheet by using fluorescent light characteristic data of a genuine paper sheet previously stored per type of the paper sheet or a threshold calculated therefrom and the acquired fluorescent light characteristic data.
    Type: Application
    Filed: September 30, 2013
    Publication date: August 4, 2016
    Applicant: GLORY LTD.
    Inventors: Yoshiki YAMAGUCHI, Takeshi SATO
  • Patent number: 9405270
    Abstract: A fixing device capable of incorporating in an image forming apparatus includes a belt unit including a rotatable elastic endless belt having a sleeve shape without a driving shaft and a nip forming member disposed contactable against an inner surface of the endless belt, and a pressing member to form a nip contact portion through which a recording medium passes by pressing against the nip forming member via the endless belt. The endless belt is configured to be removable from the fixing device without contacting the endless belt.
    Type: Grant
    Filed: January 29, 2013
    Date of Patent: August 2, 2016
    Assignee: RICOH COMPANY, LTD.
    Inventors: Tadashi Ogawa, Kenji Ishii, Teppei Kawata, Arinobu Yoshiura, Toshihiko Shimokawa, Kensuke Yamaji, Yuji Arai, Yoshiki Yamaguchi, Hiromasa Takagi, Naoki Iwaya, Takahiro Imada, Hajime Gotoh, Akira Suzuki, Masaaki Yoshikawa
  • Patent number: 9405239
    Abstract: A fixing device includes a fixing rotary body, a heat shield movably disposed opposite the fixing rotary body, an opposed body contacting the fixing rotary body to form a nip therebetween through which a recording medium is conveyed, and a temperature detector to detect a temperature of at least one of the fixing rotary body and the opposed body. A controller, operatively connected to the heat shield and the temperature detector, determines a rotation angled position to which the heat shield is moved based on a size of the recording medium and the temperature of the at least one of the fixing rotary body and the opposed body detected by the temperature detector.
    Type: Grant
    Filed: August 27, 2013
    Date of Patent: August 2, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Yutaka Ikebuchi, Takayuki Seki, Yuji Arai, Yoshiki Yamaguchi, Shuntaroh Tamaki, Kazuya Saito
  • Patent number: 9389550
    Abstract: A fixing device includes a fixing rotary body rotatable in a predetermined direction of rotation and a heater disposed opposite and heating the fixing rotary body. An opposed body contacts the fixing rotary body with releasable pressure therebetween to form a fixing nip therebetween through which a recording medium is conveyed. A heat shield is interposed between the heater and the fixing rotary body and movable in a circumferential direction of the fixing rotary body between a home position where the heat shield is disposed opposite the heater indirectly and a shield position where the heat shield is disposed opposite the heater directly to shield the fixing rotary body from the heater. A controller is operatively connected to the heat shield to move the heat shield to the home position when a print job is finished.
    Type: Grant
    Filed: January 22, 2014
    Date of Patent: July 12, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Kazuya Saito, Takayuki Seki, Yuji Arai, Ryuuichi Mimbu, Yoshiki Yamaguchi, Shuntaro Tamaki, Toshihiko Shimokawa, Hiroshi Yoshinaga, Yutaka Ikebuchi, Shuutaroh Yuasa
  • Patent number: 9383693
    Abstract: A fixing device includes a fixing rotary body and a heater for heating the fixing rotary body. An opposed body contacts the fixing rotary body with releasable pressure therebetween to form a fixing nip therebetween through which a recording medium is conveyed. A heat shield is interposed between the heater and the fixing rotary body and movable in a circumferential direction of the fixing rotary body to shield the fixing rotary body from the heater in a variable circumferential direct heating span of the fixing rotary body where the heater is disposed opposite the fixing rotary body directly. A controller is operatively connected to the heater and the heat shield to move the heat shield after the controller turns on the heater as a print job starts so as to change an area of the direct heating span of the fixing rotary body.
    Type: Grant
    Filed: February 7, 2014
    Date of Patent: July 5, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Shuutaroh Yuasa, Shuntaro Tamaki, Takayuki Seki, Hiroshi Yoshinaga, Yuji Arai, Ryuuichi Mimbu, Yoshiki Yamaguchi, Toshihiko Shimokawa, Yutaka Ikebuchi, Kazuya Saito