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: 20150063884
    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: Application
    Filed: November 7, 2014
    Publication date: March 5, 2015
    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: 8971779
    Abstract: A fixing device includes a support supporting a nip formation assembly that presses against an opposed rotary body via an endless belt to form a fixing nip between the endless belt and the opposed rotary body. The support includes a base contacting the nip formation assembly. An upstream projection projects from the base in a pressurization direction of the opposed rotary body at a position on the base corresponding to or upstream from an upstream edge of the fixing nip in a recording medium conveyance direction. A downstream projection projects from the base in the pressurization direction of the opposed rotary body at a position on the base corresponding to or downstream from a downstream edge of the fixing nip in the recording medium conveyance direction. The downstream projection is spaced apart from the upstream projection in the recording medium conveyance direction.
    Type: Grant
    Filed: November 30, 2012
    Date of Patent: March 3, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroshi Yoshinaga, 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, Arinobu Yoshiura, Hajime Gotoh, Akira Suzuki
  • Patent number: 8958710
    Abstract: A fixing device includes a controller connected to a heater and at least one of a pressing rotary body and an endless rotary body. The controller performs a first fixing operation, a first transition operation, a second fixing operation, and a second transition operation. The first fixing operation fixes a toner image on a first recording medium after the fixing device is powered on. The first transition operation rotates the pressing rotary body and the endless rotary body while controlling the heater to maintain the endless rotary body at a predetermined temperature for a first duration time. The second fixing operation fixes a toner image on a second recording medium. The second transition operation rotates the pressing rotary body and the endless rotary body while controlling the heater to maintain the endless rotary body at the predetermined temperature for a second duration time smaller than the first duration time.
    Type: Grant
    Filed: January 23, 2013
    Date of Patent: February 17, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Shuutaroh Yuasa, Takeshi Uchitani, Takamasa Hase, Takuya Seshita, Hiroshi Yoshinaga, Kenji Ishii, Tadashi Ogawa, Arinobu Yoshiura, Teppei Kawata, Toshihiko Shimokawa, Kensuke Yamaji, Masaaki Yoshikawa, Masahiko Satoh, Hiromasa Takagi, Takahiro Imada, Hajime Gotoh, Akira Suzuki, Shinichi Namekata, Kazuya Saito
  • Patent number: 8953994
    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: December 17, 2012
    Date of Patent: February 10, 2015
    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: 8953995
    Abstract: A fixing device includes an endless flexible belt, a stationary pad, a rotary pressure member, and a reinforcing member. 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 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. The reinforcing member is stationarily disposed in contact with the stationary pad inside the loop of the belt for reinforcing the stationary pad. The stationary pad includes two or more contact portions spaced apart from each other in the conveyance direction, each generally extending in the axial direction of the looped belt and protruding toward the reinforcing member to contact the reinforcing member.
    Type: Grant
    Filed: December 21, 2012
    Date of Patent: February 10, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Akira Suzuki, Masahiko Satoh, Masaaki Yoshikawa, Kenji Ishii, Hiroshi Yoshinaga, Takeshi Uchitani, Tadashi Ogawa, Hiromasa Takagi, Naoki Iwaya, Takuya Seshita, Takahiro Imada, Hajime Gotoh, Takamasa Hase, Kazuya Saito, Toshihiko Shimokawa, Shuutaroh Yuasa, Teppei Kawata, Arinobu Yoshiura, Kensuke Yamaji
  • Patent number: 8953993
    Abstract: A fixing device includes a rotatable, flexible fuser belt, a heater, a fuser pad, and a pressure member. The fuser belt is looped into a generally cylindrical configuration. The heater is disposed adjacent to the fuser belt to heat the fuser belt. The fuser pad is disposed inside the loop of the fuser belt, and has an outer peripheral surface thereof formed in a generally concave configuration. The pressure member is disposed opposite the fuser pad with the fuser belt interposed between the fuser pad and the pressure member. The pressure member presses in a load direction against the outer peripheral surface of the fuser pad through the fuser belt to form a fixing nip therebetween. The fuser pad includes, along the outer peripheral surface thereof, a protruding portion and an inwardly curved portion adjoining the protruding portion to face an outer circumferential surface of the pressure member.
    Type: Grant
    Filed: November 10, 2011
    Date of Patent: February 10, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Tetsuo Tokuda, Masaaki Yoshikawa, Kenji Ishii, Hiroshi Yoshinaga, Yuji Arai, Hiromasa Takagi, Naoki Iwaya, Yutaka Ikebuchi, Takuya Seshita, Ippei Fujimoto, Yoshiki Yamaguchi, Arinobu Yoshiura, Takahiro Imada, Hajime Gotoh, Toshihiko Shimokawa
  • Publication number: 20150023705
    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: October 7, 2014
    Publication date: January 22, 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: 8929789
    Abstract: In a fixing device, a heating element is extended along a fixing member at a location other than a nip on an inner circumferential surface side of the fixing member to generate heat. The fixing member contacts the heating element either indirectly via a gap of a prescribed size or directly contacts the heating element by with a prescribed pressure when the fixing member is rotating, and continuously separates from the heating element by a prescribed distance greater than the size of the gap when the fixing member stops rotating.
    Type: Grant
    Filed: March 6, 2012
    Date of Patent: January 6, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroshi Yoshinaga, Masaaki Yoshikawa, Kenji Ishii, Yuji Arai, Hiromasa Takagi, Naoki Iwaya, Tetsuo Tokuda, Ippei Fujimoto, Yoshiki Yamaguchi, Yutaka Ikebuchi, Takuya Seshita, Arinobu Yoshiura, Takahiro Imada, Hajime Gotoh, Toshihiko Shimokawa
  • Patent number: 8929791
    Abstract: A fixing device includes an endless flexible belt, an elongated stationary pad, a rotary pressure member, a low-friction sheet of lubricant-impregnated material, a first adhesive layer, and a second adhesive layer. 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. The low-friction sheet of lubricant-impregnated material covers the stationary pad to supply lubricant between the stationary pad and the belt across the nip. The first adhesive layer is disposed between the low-friction sheet and the stationary pad. The second adhesive layer is disposed between the low-friction sheet and the stationary pad.
    Type: Grant
    Filed: January 25, 2013
    Date of Patent: January 6, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Kenji Ishii, Masahiko Satoh, Masaaki Yoshikawa, Hiroshi Yoshinaga, Takeshi Uchitani, Tadashi Ogawa, Hiromasa Takagi, Naoki Iwaya, Takuya Seshita, Takahiro Imada, Hajime Gotoh, Takamasa Hase, Kazuya Saito, Toshihiko Shimokawa, Shuutaroh Yuasa, Teppei Kawata, Arinobu Yoshiura, Kensuke Yamaji, Akira Suzuki
  • Patent number: 8918042
    Abstract: A fixing device for fixing an image on a recording medium includes a rotatable endless fixing rotary member, a heating source which heats the fixing rotary member, an opposite rotary member in contact with the fixing rotary member, a nip forming member provided inside the fixing rotary member and in contact with the opposite rotary member via the fixing rotary member to form a nip portion to which the recording medium is fed, holding members rotatably holding end portions of the fixing rotary member, and protecting members provided between the holding members and end surfaces of the fixing rotary member to protect the end portions. Each of the protecting members has an opposite surface facing the corresponding end surface of the fixing rotary member, and including an inner diameter-side end edge having an inclined surface inclined in an inner diameter direction and away from the fixing rotary member.
    Type: Grant
    Filed: November 12, 2012
    Date of Patent: December 23, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Takahiro Imada, Masahiko Satoh, Masaaki Yoshikawa, Kenji Ishii, Tadashi Ogawa, Hiroshi Yoshinaga, Hiromasa Takagi, Kazuya Saito, Naoki Iwaya, Toshihiko Shimokawa, Kensuke Yamaji, Teppei Kawata, Takamasa Hase, Shuutaroh Yuasa, Takuya Seshita, Takeshi Uchitani, Arinobu Yoshiura, Hajime Gotoh, Akira Suzuki
  • Publication number: 20140369703
    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: September 2, 2014
    Publication date: December 18, 2014
    Inventors: Takamasa HASE, Masahiko Satoh, Shinichi Namekata, Kenji Ishii, 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
  • Patent number: 8909117
    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: December 17, 2012
    Date of Patent: December 9, 2014
    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
  • Publication number: 20140356037
    Abstract: A fixing device includes a fixing rotator, a first heat generator and a second heat generator that heat the fixing rotator, and a support disposed inside the fixing rotator. A reflector, interposed between the support and each of the first heat generator and the second heat generator, reflects light radiated from the first heat generator and the second heat generator toward the fixing rotator. The reflector includes a body mounted on the support and a shield portion projecting from the body toward the first heat generator and the second heat generator to shield the fixing rotator from the first heat generator and the second heat generator. An electric circuit is connected to the first heat generator and the second heat generator. A heat generation restrainer is provided in the electric circuit to restrict heat generation in the electric circuit.
    Type: Application
    Filed: May 15, 2014
    Publication date: December 4, 2014
    Inventors: Toshihiko SHIMOKAWA, Yutaka IKEBUCHI, Hiroshi YOSHINAGA, Takayuki SEKI, Yuji ARAI, Ryuuichi MIMBU, Shuntaro TAMAKI, Kazuya SAITO, Shuutaroh YUASA, Masaaki YOSHIKAWA, Takuya SESHITA, Hajime GOTOH, Takahiro IMADA, Kensuke YAMAJI, Akira SUZUKI
  • Publication number: 20140356038
    Abstract: A fixing device includes an endless belt or a fixing belt; a pressure member to contact an outer circumferential surface of the fixing belt; a nip forming member disposed at an interior side of the fixing belt and contacting the pressure member via the fixing belt; a heat source disposed at an interior side of the fixing belt to heat the fixing belt with radiant heat, a plurality of shielding members disposed between the heat source and the fixing belt and movable between a shielding position where the shielding member shields a non-sheet passing area on the fixing belt from the radiant heat from the heat source and a retracted position; and a controller to move the plurality of shielding members between the shielding position and the retracted position at a predetermined time.
    Type: Application
    Filed: May 21, 2014
    Publication date: December 4, 2014
    Applicant: RICOH COMPANY, LTD.
    Inventors: Yuji Arai, Takayuki Seki, Ryuuichi Mimbu, Shuntaro Tamaki, Toshihiko Shimokawa, Yutaka Ikebuchi, Shuutaroh Yuasa, Kazuya Saito, Hiroshi Yoshinaga
  • Publication number: 20140356036
    Abstract: A fixing device includes a first heat generator and a second heat generator that heat a fixing rotator. A support is disposed inside the fixing rotator. A reflector is mounted on the support and interposed between the support and each of the first heat generator and the second heat generator to reflect light radiated from the first heat generator and the second heat generator toward the fixing rotator. The reflector includes a body mounted on the support and a shield portion projecting from the body toward the first heat generator and the second heat generator to shield the fixing rotator from the first heat generator and the second heat generator. The shield portion includes a wing disposed opposite a non-conveyance span of the fixing rotator in the axial direction thereof where a recording medium is not conveyed over the fixing rotator.
    Type: Application
    Filed: May 14, 2014
    Publication date: December 4, 2014
    Inventors: Toshihiko SHIMOKAWA, Masaaki YOSHIKAWA, Takayuki SEKI, Yuji ARAI, Takeshi YAMAMOTO, Ryuuichi MIMBU, Yutaka IKEBUCHI, Takuya SESHITA, Shuntaro TAMAKI, Hajime GOTOH, Takahiro IMADA, Kazuya SAITO, Shuutaroh YUASA, Kensuke YAMAJI, Akira SUZUKI, Hiroshi YOSHINAGA
  • Patent number: 8903296
    Abstract: A fixing device includes a thermal conductor disposed inside a flexible endless fixing belt formed into a loop and configured to conduct heat from a heater to the fixing belt. The thermal conductor includes a center heating portion heated by the heater and disposed at a center of the thermal conductor in a longitudinal direction thereof orthogonal to a conveyance direction of a recording medium conveyed to the fixing belt and lateral end non-heating portions disposed at lateral ends of the thermal conductor in the longitudinal direction thereof and contiguous to the center heating portion. The center heating portion having a first diameter conducts heat from the heater to the fixing belt. The lateral end non-heating portions having a second diameter smaller than the first diameter of the center heating portion minimize conduction of heat from the heater to the fixing belt.
    Type: Grant
    Filed: December 15, 2011
    Date of Patent: December 2, 2014
    Assignee: Ricoh Company, Ltd.
    Inventors: Toshihiko Shimokawa, Yuji Arai, Hiromasa Takagi, Yoshiki Yamaguchi, Arinobu Yoshiura, Tetsuo Tokuda, Yutaka Ikebuchi, Kenji Ishii, Naoki Iwaya, Takahiro Imada, Hiroshi Yoshinaga, Takuya Seshita, Hajime Gotoh, Ippei Fujimoto, Masaaki Yoshikawa
  • Publication number: 20140341627
    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: Application
    Filed: May 5, 2014
    Publication date: November 20, 2014
    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: 20140341623
    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: Application
    Filed: May 1, 2014
    Publication date: November 20, 2014
    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
  • Publication number: 20140341626
    Abstract: A fixing device includes a fixing rotator heated by a heater and a pressing rotator to press against the fixing rotator to form a fixing nip therebetween. A heating span adjuster, interposed between the heater and the fixing rotator, is movable in a circumferential direction of the fixing rotator. The heating span adjuster moves to a retracted position where the heating span adjuster allows the heater to heat the fixing rotator in an increased axial heating span of the fixing rotator after the heater starts heating the fixing rotator until the fixing rotator and the pressing rotator start conveying the recording medium through the fixing nip. The heating span adjuster at the retracted position is outboard from a circumferential, direct heating span of the fixing rotator where the heater heats the fixing rotator directly.
    Type: Application
    Filed: May 5, 2014
    Publication date: November 20, 2014
    Inventors: Ryuuichi MIMBU, Masaaki YOSHIKAWA, Takayuki SEKI, Takeshi YAMAMOTO, Yutaka IKEBUCHI, Takuya SESHITA, Shuntaro TAMAKI, Hajime GOTOH, Takahiro IMADA, Kazuya SAITO, Toshihiko SHIMOKAWA, Shuutaroh YUASA, Kensuke YAMAJI, Akira SUZUKI, Hiroshi YOSHINAGA, Yuji ARAI
  • Publication number: 20140341625
    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: Application
    Filed: May 2, 2014
    Publication date: November 20, 2014
    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