Patents by Inventor Kensuke Yamaji

Kensuke Yamaji 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: 9158248
    Abstract: A fixing device includes a fixing rotary body and a heater disposed opposite and heating the fixing rotary body. A nip formation assembly presses against an opposed body via the fixing rotary body to form a fixing nip between the fixing rotary body and the opposed body, through which a recording medium is conveyed. A movable heat shield movable in a circumferential direction of the fixing rotary body is interposed between the heater and the fixing rotary body to shield the fixing rotary body from the heater in a variable axial span of the fixing rotary body. A stationary heat shield, interposed between the heater and the fixing rotary body to shield the fixing rotary body from the heater, is disposed outboard from a lateral edge of a heat generator of the heater in an axial direction of the fixing rotary body.
    Type: Grant
    Filed: May 1, 2014
    Date of Patent: October 13, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Yuji Arai, Masaaki Yoshikawa, Takayuki Seki, Takeshi Yamamoto, Ryuuichi Mimbu, Yutaka Ikebuchi, Takuya Seshita, Shuntaro Tamaki, Hajime Gotoh, Takahiro Imada, Kazuya Saito, Toshihiko Shimokawa, Shuutaroh Yuasa, Kensuke Yamaji, Akira Suzuki, Hiroshi Yoshinaga
  • Patent number: 9152108
    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: Grant
    Filed: October 7, 2014
    Date of Patent: October 6, 2015
    Assignee: RICOH COMPANY, LTD.
    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: 9152106
    Abstract: A fixing device includes a rotary fixing member, a heater, a pressing member, a nip formation member, a reinforcement member, a sliding sheet, and a holding member. The nip formation member is disposed at an inner circumferential side of the fixing member and pressed by the pressing member via the fixing member to form a nipping portion. The reinforcement member is stationarily disposed in an internal diameter area of the fixing member to support the nip formation member. The sliding sheet is disposed between the nip formation member and an inner circumferential face of the fixing member. The holding member is disposed at a member differing from the nip formation member to hold the sliding sheet in a state in which the sliding sheet is in close contact with a nipping face of the nip formation member facing the nipping portion.
    Type: Grant
    Filed: August 29, 2013
    Date of Patent: October 6, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Yoshiki Yamaguchi, Takayuki Seki, Yuji Arai, Yutaka Ikebuchi, Shuntaroh Tamaki, Kazuya Saito, Kenji Ishii, Tadashi Ogawa, Teppei Kawata, Toshihiko Shimokawa, Arinobu Yoshiura, Kensuke Yamaji, Hiromasa Takagi, Naoki Iwaya, Takahiro Imada, Akira Suzuki
  • Patent number: 9146508
    Abstract: A fixing device includes a fixing rotator heated by a heater and a pressing rotator pressed against the fixing rotator to form a fixing nip therebetween, through which a recording medium bearing a toner image is conveyed. A heat shield interposed between the heater and the fixing rotator is movable in a circumferential direction of the fixing rotator to shield the fixing rotator from the heater in a variable axial shield span of the fixing rotator. The fixing rotator performs fixing rotation to convey the recording medium through the fixing nip while heating the recording medium and supplemental rotation other than fixing rotation. The heat shield moves to a decreased shield span position where the heat shield shields the fixing rotator from the heater in a decreased axial shield span of the fixing rotator during supplemental rotation thereof.
    Type: Grant
    Filed: May 2, 2014
    Date of Patent: September 29, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Takahiro Imada, Masaaki Yoshikawa, Takayuki Seki, Yuji Arai, Takeshi Yamamoto, Ryuuichi Mimbu, Yutaka Ikebuchi, Takuya Seshita, Shuntaro Tamaki, Hajime Gotoh, Kazuya Saito, Toshihiko Shimokawa, Shuutaroh Yuasa, Kensuke Yamaji, Akira Suzuki, Hiroshi Yoshinaga
  • Publication number: 20150268597
    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: Application
    Filed: May 5, 2015
    Publication date: September 24, 2015
    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: 9141047
    Abstract: A fixing device capable of shifting to a sleep state includes a heat source; a rotatable fixing member that is partly heated by the heat source to heat an unfixed image carrying surface of a recording medium; a rotatable pressing member that is in pressure contact with the fixing member to form a nip portion between the pressing member and the fixing member; a rotation drive unit that directly or indirectly rotates the fixing member; a temperature detecting unit that detects a temperature of the fixing member; and a controller configured to prohibit the fixing device from shifting to the sleep state when the temperature of the fixing member in a region facing the heat source is equal to or more than a predetermined temperature T1 at a point when a predetermined time period t1 has elapsed from the stop of rotation drive of the rotation drive unit.
    Type: Grant
    Filed: April 22, 2015
    Date of Patent: September 22, 2015
    Assignee: RICOH COMPANY, LIMITED
    Inventors: Takeshi Uchitani, Masahiko Satoh, Masaaki Yoshikawa, Kenji Ishii, Tadashi Ogawa, Takahiro Imada, Hiromasa Takagi, Hiroshi Yoshinaga, Arinobu Yoshiura, Teppei Kawata, Takamasa Hase, Hajime Gotoh, Takuya Seshita, Kazuya Saito, Toshihiko Shimokawa, Kensuke Yamaji, Shuutaroh Yuasa, Akira Suzuki, Shinichi Namekata, Ryota Yamashina, Yasunori Ishigaya
  • Publication number: 20150261183
    Abstract: A fixing device includes an elastic rotator and a cooler disposed opposite the rotator to cool the rotator with cooling air. A mover contacts and moves the rotator to a first position where the rotator is disposed opposite the cooler with an increased first interval therebetween and a second position where the rotator is disposed opposite the cooler with a decreased second interval therebetween. A rectification plate is movably mounted on the cooler to contact the rotator constantly to guide the cooling air to the cooler.
    Type: Application
    Filed: March 11, 2015
    Publication date: September 17, 2015
    Applicant: Ricoh Company, Ltd.
    Inventors: Yuuki KIKUSHIMA, Masami OKAMOTO, Keisuke KUBOTA, Kenji NOZAWA, Yoshikuni SASAKI, Fumihiro HIROSE, Kensuke YAMAJI, Shuutaroh YUASA, Kaori HEMMI
  • Publication number: 20150253708
    Abstract: A fixing device includes a fixing belt stretched taut across a fixing rotator and a support rotator. A pressure rotator is pressed against the fixing rotator via the fixing belt to form a fixing nip between the fixing belt and the pressure rotator, through which a recording medium bearing a toner image is conveyed. The pressure rotator includes a recess defining an outer diameter of each lateral end of the pressure rotator in an axial direction thereof that is greater than an outer diameter of a center of the pressure rotator in the axial direction thereof A first separator is disposed downstream from the fixing nip in a recording medium conveyance direction and contacts an inner circumferential surface of the fixing belt. The first separator is isolated from the pressure rotator and includes a projection disposed opposite the recess of the pressure rotator.
    Type: Application
    Filed: March 6, 2015
    Publication date: September 10, 2015
    Inventors: Fumihiro HIROSE, Masami Okamoto, Keisuke Kubota, Kenji Nozawa, Yuuki Kikushima, Yoshikuni Sasaki, Kensuke Yamaji, Shuutaroh Yuasa, Kaori Hemmi
  • Patent number: 9116481
    Abstract: A fixing device includes a fixing rotator rotatable in a predetermined direction of rotation and a nip formation assembly contacting an inner circumferential surface of the fixing rotator. An opposed rotator presses against the nip formation assembly via the fixing rotator to form a fixing nip between the fixing rotator and the opposed rotator, through which a recording medium is conveyed. A support, disposed opposite the inner circumferential surface of the fixing rotator, supports the nip formation assembly. A heater, disposed opposite the inner circumferential surface of the fixing rotator, heats the fixing rotator. A reflector, disposed opposite an outer circumferential surface of the fixing rotator, reflects heat radiated from the fixing rotator onto the fixing rotator. The reflector spans a circumferential span of the fixing rotator where the fixing rotator is spaced apart from the support with a decreased interval therebetween.
    Type: Grant
    Filed: May 5, 2014
    Date of Patent: August 25, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Masaaki Yoshikawa, Takayuki Seki, Yuji Arai, Hiroshi Yoshinaga, Ryuuichi Mimbu, Takuya Seshita, Shuntaro Tamaki, Takeshi Yamamoto, Takahiro Imada, Hajime Gotoh, Kazuya Saito, Yutaka Ikebuchi, Toshihiko Shimokawa, Shuutaroh Yuasa, Kensuke Yamaji, Akira Suzuki
  • Publication number: 20150234329
    Abstract: According to an embodiment, provided is a fixing device that includes: a rotatable fixing member that heats a recording medium on a side carrying an unfixed image; a rotatable pressing member that is pressed and is contacted with the fixing member to form a nip portion between the pressing member and the fixing member; a heat source heating the fixing member; a relay switch provided in an energizing path for the heat source; a temperature detection sensor detecting a temperature of the fixing member; and a control unit that controls energization of the heat source according to the temperature detected by the temperature detection sensor. The control unit keeps the relay switch in an off state if the temperature of the fixing member is equal to or more than a predetermined temperature when the fixing member has stopped rotation.
    Type: Application
    Filed: May 4, 2015
    Publication date: August 20, 2015
    Inventors: Takamasa HASE, Kenji ISHII, Tadashi OGAWA, Teppei KAWATA, Arinobu YOSHIURA, Toshihiko SHIMOKAWA, Kensuke YAMAJI, Takeshi UCHITANI, Shuutaroh YUASA, Masaaki YOSHIKAWA, Hiroshi YOSHINAGA, Hiromasa TAKAGI, Naoki IWAYA, Takahiro IMADA, Hajime GOTOH, Takuya SESHITA, Ryota YAMASHINA, Yasunori ISHIGAYA
  • Publication number: 20150227095
    Abstract: A fixing device capable of shifting to a sleep state includes a heat source; a rotatable fixing member that is partly heated by the heat source to heat an unfixed image carrying surface of a recording medium; a rotatable pressing member that is in pressure contact with the fixing member to form a nip portion between the pressing member and the fixing member; a rotation drive unit that directly or indirectly rotates the fixing member; a temperature detecting unit that detects a temperature of the fixing member; and a controller configured to prohibit the fixing device from shifting to the sleep state when the temperature of the fixing member in a region facing the heat source is equal to or more than a predetermined temperature T1 at a point when a predetermined time period t1 has elapsed from the stop of rotation drive of the rotation drive unit.
    Type: Application
    Filed: April 22, 2015
    Publication date: August 13, 2015
    Inventors: Takeshi UCHITANI, Masahiko SATOH, Masaaki YOSHIKAWA, Kenji ISHII, Tadashi OGAWA, Takahiro IMADA, Hiromasa TAKAGI, Hiroshi YOSHINAGA, Arinobu YOSHIURA, Teppei KAWATA, Takamasa HASE, Hajime GOTOH, Takuya SESHITA, Kazuya SAITO, Toshihiko SHIMOKAWA, Kensuke YAMAJI, Shuutaroh YUASA, Akira SUZUKI, Shinichi NAMEKATA, Ryota YAMASHINA, Yasunori ISHIGAYA
  • Patent number: 9104156
    Abstract: A fixing device to fix an unfixed image carried on a recording medium includes an endless, rotary fixing member; a heat source to heat the fixing member; an opposed member disposed opposite the fixing member and to form a fixing nip in combination with the fixing member; and a biasing member disposed opposite the opposed member with the fixing member interposed therebetween, to press the fixing member from a back side of the fixing member against the opposed member at the fixing nip; grip portions at which the fixing member and the opposed member contact each other in areas through which the recording medium does not pass, among the fixing nip along a direction perpendicular to a conveyance direction of the recording medium; and a cleaning member to clean an outer circumference of at least one of the grip portions of the fixing member and the opposed member.
    Type: Grant
    Filed: February 25, 2014
    Date of Patent: August 11, 2015
    Assignee: Ricoh Company, LTD.
    Inventors: Akira Suzuki, Takuya Seshita, Takahiro Imada, Hajime Gotoh, Kensuke Yamaji
  • Publication number: 20150212459
    Abstract: A fixing device including a fixing member, an opposing member, a plurality of heat sources, and a voltage detector. The opposing member is disposed opposite the fixing member to contact the fixing member to form a nip portion at which an unfixed image on a recording medium is fixed. The plurality of heat sources heats the fixing member. The voltage detector detects an applied voltage of at least one of the plurality of heat sources. Upon detection of the applied voltage of the heat sources by the voltage detector, a voltage is applied to at least one of the heat sources.
    Type: Application
    Filed: April 9, 2015
    Publication date: July 30, 2015
    Applicant: Ricoh Company, Ltd.
    Inventors: Takamasa HASE, Masahiko SATOH, Masaaki YOSHIKAWA, Kenji ISHII, Hiroshi YOSHINAGA, Tadashi OGAWA, Takeshi UCHITANI, Hiromasa TAKAGI, Naoki IWAYA, Teppei KAWATA, Takuya SESHITA, Arinobu YOSHIURA, Takahiro IMADA, Hajime GOTOH, Kazuya SAITO, Toshihiko SHIMOKAWA, Shuutaroh YUASA, Kensuke YAMAJI, Akira SUZUKI
  • Patent number: 9069304
    Abstract: In the present invention, upon return from a standby mode or sleep mode, image data is acquired as warming-up time estimate information for estimating the warming-up time to increase the temperature of a fixing belt to a target fixing temperature and, if the acquired image data is the data on a black-and-white image, control is performed to delay the heating start timing of the fixing belt.
    Type: Grant
    Filed: November 5, 2013
    Date of Patent: June 30, 2015
    Assignee: Ricoh Company, Limited
    Inventors: Takuya Seshita, Masahiko Satoh, Masaaki Yoshikawa, Hiroshi Yoshinaga, Naoki Iwaya, Hiromasa Takagi, Takahiro Imada, Hajime Gotoh, Akira Suzuki, Kenji Ishii, Tadashi Ogawa, Teppei Kawata, Arinobu Yoshiura, Toshihiko Shimokawa, Kensuke Yamaji, Takeshi Uchitani, Takamasa Hase, Shuutaroh Yuasa
  • Patent number: 9063480
    Abstract: In an embodiment, provided is a fixing device that includes: a fixing belt rotatable and endless; a belt holding member holding the fixing belt at each end part in an axial direction; a heat source heating the fixing belt; a nip forming member provided inside the fixing belt; an opposing rotator forming a nip portion between the opposing rotator and the fixing belt via the fixing belt; and a separating member that extends near the nip portion and separates a recording medium from a surface of the fixing belt. A leading end of the separating member is provided with a receding portion and an approaching portion that is at a different position from a position of the receding portion different in the axial direction. The approaching portion is provided nearer to the nip portion than the receding portion is provided.
    Type: Grant
    Filed: December 27, 2012
    Date of Patent: June 23, 2015
    Assignee: Ricoh Company, Limited
    Inventors: Arinobu Yoshiura, Masahiko Satoh, Masaaki Yoshikawa, Kenji Ishii, Tadashi Ogawa, Takahiro Imada, Hiromasa Takagi, Kazuya Saito, Naoki Iwaya, Toshihiko Shimokawa, Kensuke Yamaji, Teppei Kawata, Takamasa Hase, Shuutaroh Yuasa, Takuya Seshita, Takeshi Uchitani, Hajime Gotoh, Akira Suzuki, Hiroshi Yoshinaga
  • Patent number: 9063493
    Abstract: A fixing device includes an endless flexible belt, an elongated stationary pad, a rotary pressure member, and a low-friction sheet. The endless flexible belt is looped into a generally cylindrical configuration extending in an axial direction thereof for rotation in a rotational, circumferential direction thereof. The elongated stationary pad is stationarily disposed inside the loop of the belt. The rotary pressure member is disposed parallel to the belt. The rotary pressure member presses against the stationary pad via the belt to form a nip therebetween, through which a recording medium is conveyed in a conveyance direction. The low-friction sheet of lubricant-impregnated material covers the stationary pad to supply a lubricant between the stationary pad and the belt across the nip. The low-friction sheet has one or more flow channels defined therein.
    Type: Grant
    Filed: January 24, 2013
    Date of Patent: June 23, 2015
    Assignee: RICOH COMPANY, LTD.
    Inventors: Kensuke Yamaji, Masahiko Satoh, Masaaki Yoshikawa, Kenji Ishii, Hiroshi Yoshinaga, Tadashi Ogawa, Takeshi Uchitani, Hiromasa Takagi, Takuya Seshita, Teppei Kawata, Arinobu Yoshiura, Takahiro Imada, Hajime Gotoh, Takamasa Hase, Toshihiko Shimokawa, Shuutaroh Yuasa, Akira Suzuki
  • Publication number: 20150168897
    Abstract: A fixing device includes at least one heater disposed opposite an inner circumferential surface of an endless rotary body to heat the endless rotary body and a shield interposed between the endless rotary body and the at least one heater to shield the endless rotary body from heat radiated from the at least one heater. A first size recording medium passes over a first passage region of the endless rotary body and a second size recording medium passes over a second passage region of the endless rotary body. The shield includes a notch disposed opposite a lateral end of the second passage region of the endless rotary body in an axial direction thereof. The lateral end of the second passage region overlaps a non-passage region of the endless rotary body in the axial direction thereof where the first size recording medium does not pass.
    Type: Application
    Filed: February 25, 2015
    Publication date: June 18, 2015
    Inventors: Tadashi OGAWA, Masahiko Satoh, Masaaki Yoshikawa, Hiroshi Yoshinaga, Kenji Ishii, Takeshi Uchitani, Hiromasa Takagi, Naoki Iwaya, Takuya Seshita, Takahiro Imada, Hajime Gotoh, Takamasa Hase, Toshihiko Shimokawa, Shuutaroh Yuasa, Teppei Kawata, Arinobu Yoshiura, Kensuke Yamaji, Akira Suzuki
  • Patent number: 9052658
    Abstract: A fixing device for fixing an unfixed image onto a recording medium includes a fixing belt, a nip forming member, an opposing rotary member, a heater, and a temperature detector. The fixing belt is formed into a loop to move endlessly and fix the unfixed image on the recording medium. The nip forming member is disposed inside the loop formed by the fixing belt. The opposing rotary member contacts the nip forming member via the fixing belt to form a nip portion therebetween while rotating. The heater heats the fixing belt at a place other than the nip portion. The temperature detector detects a temperature of the surface of the fixing belt. The temperature detector detects the temperature near a place of the fixing belt that easily deforms as the fixing belt is heated by the heater.
    Type: Grant
    Filed: January 28, 2013
    Date of Patent: June 9, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Takeshi Uchitani, Masahiko Satoh, Masaaki Yoshikawa, Kenji Ishii, Tadashi Ogawa, Takahiro Imada, Hiromasa Takagi, Kazuya Saito, Naoki Iwaya, Toshihiko Shimokawa, Kensuke Yamaji, Teppei Kawata, Takamasa Hase, Takuya Seshita, Shuutaroh Yuasa, Arinobu Yoshiura, Hajime Gotoh, Akira Suzuki, Hiroshi Yoshinaga
  • Patent number: 9046838
    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: August 30, 2013
    Date of Patent: June 2, 2015
    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: 9046839
    Abstract: A fixing device includes a fixing rotator rotatable in a predetermined direction of rotation, a heater disposed opposite the fixing rotator to heat the fixing rotator, and an opposed rotator contacting an outer circumferential surface of the fixing rotator. A heat shield interposed between the heater and the fixing rotator shields the fixing rotator from the heater. A support supports the heat shield. The heat shield includes a first section supported by the support and having a decreased thermal conductivity and a second section abutting the first section in an axial direction of the heat shield and having an increased thermal conductivity greater than the decreased thermal conductivity of the first section.
    Type: Grant
    Filed: May 1, 2014
    Date of Patent: June 2, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Yuji Arai, Masaaki Yoshikawa, Takayuki Seki, Takeshi Yamamoto, Ryuuichi Mimbu, Yutaka Ikebuchi, Takuya Seshita, Shuntaro Tamaki, Hajime Gotoh, Takahiro Imada, Kazuya Saito, Toshihiko Shimokawa, Shuutaroh Yuasa, Kensuke Yamaji, Akira Suzuki, Hiroshi Yoshinaga, Yoshio Hattori