Patents by Inventor Toshihiko Shimokawa

Toshihiko Shimokawa 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: 20160154350
    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: Application
    Filed: November 25, 2015
    Publication date: June 2, 2016
    Applicant: Ricoh Company, Ltd.
    Inventors: Kazuya Saito, Ryuuichi Mimbu, Toshihiko Shimokawa, Haruyuki Honda, Yoshiki Yamaguchi, Yasunori Ishigaya, Keitaro Shoji, Yutaka Ikebuchi, Yoshio Hattori
  • Patent number: 9348272
    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 to form a fixing nip therebetween through which a recording medium is conveyed. A heat shield is movable in a circumferential direction of the fixing rotary body and interposed between the heater and the fixing rotary body to shield the fixing rotary body from the heater. A driver is connected to the heat shield to drive and move the heat shield between a shield position where the heat shield is interposed between the heater and the fixing rotary body to shield the fixing rotary body from the heater and a retracted position where the heat shield is retracted from the shield position. A reinforcement is mounted on a long edge of the heat shield.
    Type: Grant
    Filed: December 26, 2013
    Date of Patent: May 24, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Shuntaroh Tamaki, Takayuki Seki, Hiroshi Yoshinaga, Yuji Arai, Ryuuichi Mimbu, Yoshiki Yamaguchi, Yutaka Ikebuchi, Kazuya Saito, Toshihiko Shimokawa, Shuutaroh Yuasa
  • Publication number: 20160124359
    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: Application
    Filed: October 23, 2015
    Publication date: May 5, 2016
    Applicant: RICOH COMPANY, LTD.
    Inventors: Yutaka Ikebuchi, Yoshio Hattori, Ryuuichi Mimbu, Yasunori Ishigaya, Yoshiki Yamaguchi, Kazuya Saito, Toshihiko Shimokawa, Keitaro Shoji
  • Publication number: 20160116869
    Abstract: A fixing device includes a fixing rotator rotatable in a predetermined direction of rotation and a pressure rotator pressed against the fixing rotator to form a fixing nip therebetween, through which a recording medium bearing a toner image is conveyed. A plurality of heaters heats the fixing rotator. A sensor is disposed opposite the fixing rotator and includes a plurality of temperature detection elements to detect a temperature of the fixing rotator at a plurality of spots thereon arranged in an axial direction of the fixing rotator. A controller is operatively connected to the sensor and the plurality of heaters to control the plurality of heaters based on the temperature of the fixing rotator detected by the sensor and predict a width of the recording medium in the axial direction of the fixing rotator to be conveyed to the fixing nip.
    Type: Application
    Filed: September 14, 2015
    Publication date: April 28, 2016
    Inventors: Kazuya SAITO, Ryuuichi MIMBU, Toshihiko SHIMOKAWA, Haruyuki HONDA, Yoshiki YAMAGUCHI, Yasunori ISHIGAYA, Yoshio HATTORI
  • Patent number: 9316964
    Abstract: A fixing device includes a first rotator and a second rotator pressed against the first rotator to form a fixing nip therebetween, through which a recording medium bearing a toner image is conveyed. A thermal insulation cover is disposed opposite the second rotator. A mover is connected to the second rotator to move the second rotator with respect to the first rotator. The mover is coupled with the thermal insulation cover to move the thermal insulation cover while retaining a predetermined interval between the thermal insulation cover and the second rotator.
    Type: Grant
    Filed: March 13, 2015
    Date of Patent: April 19, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Yoshiki Yamaguchi, Yoshio Hattori, Ryuuichi Mimbu, Yasunori Ishigaya, Toshihiko Shimokawa, Kazuya Saito, Haruyuki Honda
  • Patent number: 9316968
    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. A heat shield is movable in a circumferential direction of the fixing rotary body and interposed between the heater and the fixing rotary body to shield the fixing rotary body from the heater. A driver is connected to the heat shield to drive and move the heat shield within a circumferential moving span in the circumferential direction of the fixing rotary body. An abnormal temperature detector detects an abnormal temperature of the fixing rotary body that is not lower than a predetermined temperature. The abnormal temperature detector is disposed opposite a circumferential outboard span outboard from the circumferential moving span of the heat shield in the circumferential direction of the fixing rotary body.
    Type: Grant
    Filed: December 26, 2013
    Date of Patent: April 19, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Kazuya Saito, Takayuki Seki, Hiroshi Yoshinaga, Yuji Arai, Ryuuichi Mimbu, Yutaka Ikebuchi, Yoshiki Yamaguchi, Shuntaroh Tamaki, Toshihiko Shimokawa, Shuutaroh Yuasa
  • Patent number: 9316972
    Abstract: A fixing device includes a fixing rotary body rotatable in a given direction of rotation and a pressing rotary body pressed against the fixing rotary body to form a fixing nip therebetween through which a recording medium bearing a toner image is conveyed. A heater is disposed inside the fixing rotary body to heat the fixing rotary body. A reflector, disposed opposite an inner circumferential surface of the fixing rotary body via the heater, reflects light emitted from the heater onto the fixing rotary body. The reflector includes a movable portion movable relative to the heater to direct the light emitted from the heater onto a variable heating span of the fixing rotary body spanning in an axial direction thereof. The variable heating span varies depending on a width of the recording medium in the axial direction of the fixing rotary body.
    Type: Grant
    Filed: June 28, 2013
    Date of Patent: April 19, 2016
    Assignee: RICOH COMPANY, LTD.
    Inventors: Yuji Arai, Masaaki Yoshikawa, Kenji Ishii, Tadashi Ogawa, Teppei Kawata, Arinobu Yoshiura, Toshihiko Shimokawa, Kensuke Yamaji, Yoshiki Yamaguchi, Hiromasa Takagi, Naoki Iwaya, Takahiro Imada, Hajime Gotoh, Akira Suzuki
  • Patent number: 9310733
    Abstract: A fixing device includes a substantially cylindrical metal member, a heater, an endless, flexible fixing member, a rotary pressing member, and a stationary member. The heater heats the metal member. The fixing member is disposed rotatable around the metal member. An inner circumferential surface of the fixing member is heated by the metal member to heat and fix a toner image. The rotary pressing member is disposed opposite the metal member and pressed against an outer circumferential surface of the fixing member to form a nip between the rotary pressing member and the fixing member through which a recording medium bearing the toner image passes. The stationary member is disposed in pressure contact with the inner circumferential surface of the fixing member, and has an opposing face opposing the rotary pressing member and having a curvature smaller than a curvature of the rotary pressing member.
    Type: Grant
    Filed: February 4, 2011
    Date of Patent: April 12, 2016
    Assignee: Ricoh Company, LTD.
    Inventors: Hiroshi Yoshinaga, Masaaki Yoshikawa, Kenichi Hasegawa, Kenji Ishii, Akira Shinshi, Naoki Iwaya, Yutaka Ikebuchi, Ippei Fujimoto, Yoshiki Yamaguchi, Shuntaroh Tamaki, Tetsuo Tokuda, Takamasa Hase, Takahiro Imada, Toshihiko Shimokawa
  • Publication number: 20160098003
    Abstract: A fixing device includes a heat source; a fixing member looped into a generally cylindrical shape to rotate in a circumferential direction thereof and partially heated by the heat source and to heat a surface of a recording medium bearing an unfixed toner image to fix the unfixed toner image thereon in a fixing process; a rotary pressing member disposed facing the fixing member to form a nip therebetween, through which the recording medium is transported in a transport direction; and a rotation driver to rotate one of the fixing member and the pressing member. In a case in which the fixing member is halted for a reason other than the fixing process while power of the fixing device is on, electric power is not supplied to the heat source and the fixing member is rotated by a predetermined amount or more after the fixing member is halted.
    Type: Application
    Filed: December 11, 2015
    Publication date: April 7, 2016
    Inventors: Takeshi UCHITANI, Masahiko SATOH, Kenji ISHII, Tadashi OGAWA, Teppei KAWATA, Arinobu YOSHIURA, Toshihiko SHIMOKAWA, Kensuke YAMAJI, Takamasa HASE, Shuutaroh YUASA, Masaaki YOSHIKAWA, Hiromasa TAKAGI, Takahiro IMADA, Hajime GOTOH, Akira SUZUKI, Takuya SESHITA, Hiroshi YOSHINAGA, Kazuya SAITO, Shinichi NAMEKATA, Takayuki SEKI, Yuji ARAI, Ryuuichi MIMBU, Yoshiki YAMAGUCHI, Shuntaroh TAMAKI, Yutaka IKEBUCHI
  • Patent number: 9291967
    Abstract: A fixing device that fixes an image on a recording medium includes a rotatable endless belt, deployed in a loop supported by rollers, a nip forming member provided inside the loop formed by the belt, a support member that supports the nip forming member, a counter rotation body disposed outside the loop formed by the belt and configured to form a nip with the belt by being in contact with the nip forming member through the belt, and a heat source configured to heat the belt directly by a radiant heat except at the nip. The support member includes a base portion that contacts the nip forming member and two arms extending from the base portion in a direction away from the nip forming member to partially surround a part of heat generating portion of the heat source.
    Type: Grant
    Filed: November 7, 2014
    Date of Patent: March 22, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Naoki Iwaya, Masahiko Satoh, Masaaki Yoshikawa, Kenji Ishii, Hiroshi Yoshinaga, Tadashi Ogawa, Takeshi Uchitani, Hiromasa Takagi, Takuya Seshita, Takahiro Imada, Takamasa Hase, Hajime Gotoh, Arinobu Yoshiura, Teppei Kawata, Toshihiko Shimokawa, Shuutaroh Yuasa, Kazuya Saito, Kensuke Yamaji, Akira Suzuki
  • Patent number: 9285728
    Abstract: An image forming apparatus includes a fixing device including 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 halts the heat shield instantly when a fault occurs during a print job.
    Type: Grant
    Filed: December 30, 2013
    Date of Patent: March 15, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroshi Yoshinaga, Takayuki Seki, Yuji Arai, Yutaka Ikebuchi, Ryuuichi Mimbu, Yoshiki Yamaguchi, Shuntaro Tamaki, Kazuya Saito, Shuutaroh Yuasa, Toshihiko Shimokawa
  • Publication number: 20160054691
    Abstract: An image forming apparatus includes a fixing device. The fixing device includes a rotatable endless fixing member, a nip forming member arranged inside the fixing member, a pressing member in contact with the nip forming member via the fixing member, and a heating source configured to heat the fixing member. When an abnormality occurs in at least one of the fixing device and other devices included in the image forming apparatus, a rotation of the fixing member is stopped prior to stopping a rotation driving of a discharging unit and, after stopping, the fixing member is controlled to rotate.
    Type: Application
    Filed: October 30, 2015
    Publication date: February 25, 2016
    Inventors: Takamasa HASE, Masahiko SATOH, Shinichi NAMEKATA, Kenji ISHll, Takeshi UCHITANI, Tadashi OGAWA, Teppei KAWATA, Arinobu YOSHIURA, Kazuya SAITO, Toshihiko SHIMOKAWA, Shuutaroh YUASA, Kensuke YAMAJI, Masaaki YOSHIKAWA, Hiroshi YOSHINAGA, Hiromasa TAKAGI, Naoki IWAYA, Takuya SESHITA, Takahiro IMADA, Hajime GOTOH, Akira SUZUKI
  • Publication number: 20160033910
    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: Application
    Filed: July 22, 2015
    Publication date: February 4, 2016
    Applicant: RICOH COMPANY, LTD.
    Inventors: Toshihiko Shimokawa, Ryuuichi Mimbu, Kazuya Saito, Haruyuki Honda, Yoshiki Yamaguchi, Yasunori Ishigaya, Yoshio Hattori
  • Patent number: 9239553
    Abstract: A fixing device includes a fixing rotary body and a heater disposed opposite the fixing rotary body. A heat shield is movable in a circumferential direction of the fixing rotary body and interposed between the heater and the fixing rotary body to shield the fixing rotary body from the heater. An overheating suppressor is interposed between the heater and the heat shield to shield the heat shield from the heater. The heat shield includes an intermediate portion spanning in the circumferential direction of the fixing rotary body and movable between a shield position where the intermediate portion is disposed opposite the heater directly and a retracted position where the intermediate portion is disposed opposite the heater via the overheating suppressor.
    Type: Grant
    Filed: May 5, 2015
    Date of Patent: January 19, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Yuji Arai, Takayuki Seki, Yoshiki Yamaguchi, Shuntaroh Tamaki, Yutaka Ikebuchi, Kazuya Saito, Kenji Ishii, Tadashi Ogawa, Teppei Kawata, Arinobu Yoshiura, Toshihiko Shimokawa, Kensuke Yamaji, Masaaki Yoshikawa, Hiromasa Takagi, Naoki Iwaya, Takahiro Imada, Hajime Gotoh, Akira Suzuki, Hiroshi Yoshinaga, Ryuuichi Mimbu, Takuya Seshita, Takeshi Yamamoto, Shuutaroh Yuasa
  • Patent number: 9239559
    Abstract: A fixing device includes a heat source; a fixing member looped into a generally cylindrical shape to rotate in a circumferential direction thereof and partially heated by the heat source and to heat a surface of a recording medium bearing an unfixed toner image to fix the unfixed toner image thereon in a fixing process; a rotary pressing member disposed facing the fixing member to form a nip therebetween, through which the recording medium is transported in a transport direction; and a rotation driver to rotate one of the fixing member and the pressing member. In a case in which the fixing member is halted for a reason other than the fixing process while power of the fixing device is on, electric power is not supplied to the heat source and the fixing member is rotated by a predetermined amount or more after the fixing member is halted.
    Type: Grant
    Filed: February 8, 2013
    Date of Patent: January 19, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Takeshi Uchitani, Masahiko Satoh, Kenji Ishii, Tadashi Ogawa, Teppei Kawata, Arinobu Yoshiura, Toshihiko Shimokawa, Kensuke Yamaji, Takamasa Hase, Shuutaroh Yuasa, Masaaki Yoshikawa, Hiromasa Takagi, Takahiro Imada, Hajime Gotoh, Akira Suzuki, Takuya Seshita, Hiroshi Yoshinaga, Kazuya Saito, Shinichi Namekata, Takayuki Seki, Yuji Arai, Ryuuichi Mimbu, Yoshiki Yamaguchi, Shuntaroh Tamaki, Yutaka Ikebuchi
  • Patent number: 9235177
    Abstract: A fixing device comprises a rotatable fixing member to apply heat to a recording medium bearing an unfixed image thereon, a heat source to heat the fixing member, and a rotatable pressing member pressing against the fixing member forming a nip therebetween. A driving source rotates and drives the fixing member and the pressing member. An overheat safety device has a relay to open and close a power supply path connected to the heat source. A temperature detector is connected to both the relay and the control unit to detect temperature of the fixing member. The overheat safety device turns off the relay and cuts off power supply to the heat source when the fixing member is overheated. The fixing member is allowed to radiate heat and cool down when the temperature detected by the temperature detector is more than a prescribed level.
    Type: Grant
    Filed: December 31, 2012
    Date of Patent: January 12, 2016
    Assignee: Ricoh Company, Ltd.
    Inventors: Takuya Seshita, Masahiko Satoh, Masaaki Yoshikawa, Hiroshi Yoshinaga, Kenji Ishii, Tadashi Ogawa, Takahiro Imada, Hiromasa Takagi, Kazuya Saito, Naoki Iwaya, Toshihiko Shimokawa, Kensuke Yamaji, Teppei Kawata, Takamasa Hase, Shuutaroh Yuasa, Takeshi Uchitani, Arinobu Yoshiura, Hajime Gotoh, Akira Suzuki, Ryota Yamashina, Yasunori Ishigaya
  • Publication number: 20160004197
    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: September 11, 2015
    Publication date: January 7, 2016
    Applicant: 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: 9229379
    Abstract: A fixing device includes a rotatable fixing member; a heating source configured to heat the fixing member; an opposing member configured to come into contact with an outer circumferential surface of the fixing member to form a nip portion; and a shielding member configured to block heat from the heating source. The shielding member is configured to rotate about a position different from the center of the heating source so as to be movable between a shielding position and a retraction position. The shielding position is a position where the shielding member comes close to the heating source to block heat from the heating source to the fixing member. The retraction position being a position where the shielding member is retracted away from the shielding position.
    Type: Grant
    Filed: August 30, 2013
    Date of Patent: January 5, 2016
    Assignee: RICOH COMPANY, LIMITED
    Inventors: Shuntaroh Tamaki, Takayuki Seki, Yuji Arai, Yoshiki Yamaguchi, Yutaka Ikebuchi, Kazuya Saito, Naoki Iwaya, Toshihiko Shimokawa
  • Publication number: 20150378290
    Abstract: A fixing device includes an endless belt rotatable in a predetermined direction of rotation and a nip formation assembly disposed opposite an inner circumferential surface of the endless belt. An opposed rotary body is pressed against the nip formation assembly via the endless belt to form a fixing nip between the endless belt and the opposed rotary body through which a recording medium bearing a toner image is conveyed. A belt holder contacts and supports each lateral end of the endless belt in an axial direction thereof. The belt holder is isolated from the opposed rotary body with a first interval interposed therebetween in the axial direction of the endless belt.
    Type: Application
    Filed: September 8, 2015
    Publication date: December 31, 2015
    Inventors: Teppei KAWATA, Masahiko Satoh, Masaaki Yoshikawa, Kenji Ishii, Hiroshi Yoshinaga, Tadashi Ogawa, Takahiro Imada, Hiromasa Takagi, Kazuya Saito, Naoki Iwaya, Kensuke Yamaji, Takamasa Hase, Toshihiko Shimokawa, Shuutaroh Yuasa, Takuya Seshita, Takeshi Uchitani, Arinobu Yoshiura, Hajime Gotoh, Akira Suzuki
  • Patent number: 9221661
    Abstract: A pressure adjuster for changing pressure between a plurality of opposed bodies pressed against each other includes a cam rotatable in a given direction of rotation and having a top dead center on an outer circumferential surface thereof that is distanced farthest from a rotation axis of the cam. A driver is connected to the cam to drive and rotate the cam. A cam rest contacts the cam and is connected to one of the plurality of opposed bodies. A cam regulation assembly is connected to the cam to regulate rotation of the cam at least when the top dead center of the cam passes a contact position where the cam contacts the cam rest.
    Type: Grant
    Filed: February 28, 2014
    Date of Patent: December 29, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Ryuuichi Mimbu, Takayuki Seki, Hiroshi Yoshinaga, Yuji Arai, Yutaka Ikebuchi, Yoshiki Yamaguchi, Kazuya Saito, Shuutaroh Yuasa, Shuntaro Tamaki, Toshihiko Shimokawa, Naoki Iwaya