Patents by Inventor Hiroshi Yoshinaga

Hiroshi Yoshinaga 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: 10001735
    Abstract: A fixing device may include an endless fixing member; a heater inside the fixing member; and a nip forming unit configured to form a nip through which a recording sheet is conveyed, the nip forming unit including a supporting member and a contact member supported by the supporting member, the supporting member including at least one contact surface and the contact member including a plurality of protrusions protruding towards the supporting member such that two or more of the plurality of protrusions are configured to contact one of the at least one contact surface of the supporting member, each of the plurality of protrusions having a height associated there with such that the height of the plurality of protrusions increases in a direction from ends of the contact member towards a center of the contact member.
    Type: Grant
    Filed: December 20, 2016
    Date of Patent: June 19, 2018
    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
  • Publication number: 20180157198
    Abstract: A fixing device includes a belt, a pressure rotator disposed opposite the belt, and a nip formation unit that forms a fixing nip between the belt and the pressure rotator. The nip formation unit includes a guide face disposed upstream from the fixing nip in a rotation direction of the belt and contoured to separate from the pressure rotator in a direction opposite the rotation direction of the belt. The guide face is adhered with a lubricant moved from an inner circumferential surface of the belt. The belt rotates in the rotation direction when an outer circumferential surface of the belt has a temperature lower than a fixing temperature at which the belt fixes a toner image on a recording medium. The belt rotating in the rotation direction brings the lubricant adhered to the guide face into contact with the belt.
    Type: Application
    Filed: November 6, 2017
    Publication date: June 7, 2018
    Inventors: Takashi SETO, Kenji ISHII, Hiroshi YOSHINAGA, Takayuki SEKI, Ippei FUJIMOTO, Hiroyuki SHIMADA, Kazunari SAWADA, Ryohei MATSUDA
  • Patent number: 9989905
    Abstract: A fixing device includes a nip formation pad which is disposed opposite an endless belt and forms a fixing nip between the endless belt and a pressure rotator. A contact heater is disposed at least at one lateral end of the nip formation pad in a longitudinal direction thereof and heats at least one lateral end of the endless belt in an axial direction thereof. A thermal conduction aid contacts a belt-side face of each of the nip formation pad and the contact heater and conducts heat in the axial direction of the endless belt. A cover is disposed outboard from the thermal conduction aid in a longitudinal direction thereof. The cover covers the belt-side face of the contact heater. The contact heater includes a power supply portion disposed outboard from the thermal conduction aid in the longitudinal direction thereof and covered by the cover.
    Type: Grant
    Filed: May 24, 2017
    Date of Patent: June 5, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Takayuki Seki, Takashi Seto, Hiroshi Yoshinaga, Kenji Ishii, Ippei Fujimoto, Kazunari Sawada
  • Patent number: 9983526
    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: June 9, 2017
    Date of Patent: May 29, 2018
    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: 9971289
    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: Grant
    Filed: May 23, 2017
    Date of Patent: May 15, 2018
    Assignee: RICOH COMPANY, LTD.
    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: 9964905
    Abstract: A fixing device includes a fixing rotator and at least one heater, disposed opposite an inner circumferential surface of the fixing rotator, to heat the fixing rotator. The at least one heater includes a heat generator to generate heat. A lateral end heater is disposed at least at one lateral end of a nip formation pad in a longitudinal direction of the nip formation pad. The lateral end heater heats at least one lateral end of the fixing rotator in an axial direction of the fixing rotator. The lateral end heater includes a base, a resistor, mounted on the base, to generate heat, and an electrode coupled to the resistor to supply power to the resistor. The electrode is disposed outboard from the heat generator of the at least one heater in the axial direction of the fixing rotator.
    Type: Grant
    Filed: December 14, 2016
    Date of Patent: May 8, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Takayuki Seki, Kenji Ishii, Kazuhito Kishi, Takashi Seto, Hiroshi Yoshinaga, Ippei Fujimoto, Misaki Shimizu, Kazunari Sawada
  • Publication number: 20180120741
    Abstract: An image forming apparatus includes a fixing device that includes a heater to heat a fixing rotator, an opposed rotator to press against the fixing rotator to form a fixing nip therebetween, and at least one rotary body to convey a recording medium to the fixing nip. A controller rotates the fixing rotator in a forward direction to fix a toner image on the recording medium. The controller stops the heater and rotates the fixing rotator in a predetermined rotation direction when a failure occurs while the fixing device is activated. The controller determines that the predetermined rotation direction is the forward direction or a backward direction according to the at least one rotary body that sandwiches the recording medium, if the fixing nip and the at least one rotary body sandwich the recording medium simultaneously when the failure occurs while the fixing device is activated.
    Type: Application
    Filed: October 13, 2017
    Publication date: May 3, 2018
    Inventors: Hiroshi YOSHINAGA, Kenji Ishii, Hiroyuki Shimada, Ippei Fujimoto, Takashi Seto, Takayuki Seki, Kazunari Sawada
  • Patent number: 9933730
    Abstract: A fixing device includes an endless belt, a first radiant heater including a first heat generator to heat the endless belt, and a second radiant heater including a second heat generator, disposed outboard from the first heat generator in an axial direction of the endless belt, to heat the endless belt. A nip formation pad includes a nip-side face disposed opposite the endless belt. A contact heater heats at least one lateral end of the endless belt in the axial direction of the endless belt. The contact heater includes a nip-side face disposed opposite the endless belt. A thermal conduction aid covers the nip-side face of the nip formation pad and the nip-side face of the contact heater and conducts heat applied to the endless belt in the axial direction of the endless belt.
    Type: Grant
    Filed: December 13, 2016
    Date of Patent: April 3, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroshi Yoshinaga, Kenji Ishii, Kazuhito Kishi, Takashi Seto, Takayuki Seki, Ippei Fujimoto, Kazunari Sawada
  • Patent number: 9927748
    Abstract: A fixing device includes: a rotatable endless fixing belt; a nip forming member arranged inside the fixing belt; a facing rotating body that abuts the nip forming member via the fixing belt to form a nip portion with the fixing belt; a heat source that directly heats up the fixing belt at a portion other than the nip portion; and a supporting member that supports the nip forming member. The fixing device conveys a recording medium carrying an unfixed image to the nip portion to fix the unfixed image to the recording medium, and the supporting member includes a rising portion extending in an abutting direction of the facing rotating body against the fixing belt and having a tip close to an inner circumferential surface of the fixing belt, and is set to have a section modulus of 200 mm3 or higher.
    Type: Grant
    Filed: January 28, 2013
    Date of Patent: March 27, 2018
    Assignee: RICOH COMPANY, LTD.
    Inventors: Hiroshi Yoshinaga, Masahiko Satoh, Masaaki Yoshikawa, Kenji Ishii, Tadashi Ogawa, Hiromasa Takagi, Naoki Iwaya, Takuya Seshita, Takahiro Imada, Hajime Gotoh, Akira Suzuki, Teppei Kawata, Toshihiko Shimokawa, Arinobu Yoshiura, Takamasa Hase, Takeshi Uchitani, Shuutaroh Yuasa, Kensuke Yamaji
  • Publication number: 20180059587
    Abstract: A fixing device includes a heat generator being disposed inside a loop formed by a rotator and including a heat generating portion to radiate radiant heat. A reflector is disposed inside the loop formed by the rotator and includes a reflection face to reflect the radiant heat radiated from the heat generator toward the rotator. A support supports the reflector. A holder holds each lateral end of the support in a longitudinal direction of the support, which is perpendicular to the rotation direction of the rotator. A fastener attaches the reflector to the support at an attachment position disposed at each lateral end of the reflector in a longitudinal direction of the reflector. The attachment position is disposed outboard from a lateral edge of the heat generating portion of the heat generator and disposed inboard from the holder in the longitudinal direction of the reflector.
    Type: Application
    Filed: August 23, 2017
    Publication date: March 1, 2018
    Inventors: Kazunari Sawada, lppei Fujimoto, Kenji Ishii, Hiroyuki Shimada, Takashi Seto, Hiroshi Yoshinaga, Takayuki Seki
  • Publication number: 20180046121
    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 30, 2017
    Publication date: February 15, 2018
    Inventors: Teppei KAWATA, Masahiko SATOH, Masaaki YOSHIKAWA, Kenji ISHll, 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: 9874839
    Abstract: A fixing device includes a fixing rotator rotatable in a predetermined direction of rotation and a nip formation pad disposed inside the fixing rotator. A pressure rotator presses against the nip formation pad via the fixing rotator to form a fixing nip between the fixing rotator and the pressure rotator. A heat generator is disposed inside the fixing rotator to heat the fixing rotator. A reflector is interposed between the heat generator and the nip formation pad. The reflector includes a reflection face to reflect radiant heat radiated from the heat generator. The reflection face includes a reflection portion disposed opposite the heat generator at various angles. A support is provided separately from the nip formation pad and supports the reflector.
    Type: Grant
    Filed: June 9, 2016
    Date of Patent: January 23, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Kazunari Sawada, Kenji Ishii, Kazuhito Kishi, Takayuki Seki, Hiroshi Yoshinaga, Takashi Seto, Hiromasa Takagi, Ippei Fujimoto, Takamasa Hase, Yasuhiko Ogino, Shohta Kobashigawa
  • Publication number: 20180017910
    Abstract: A fixing device includes a nip former including a first face to form a fixing nip, a second face being disposed upstream from the first face in a rotation direction of a rotator and defining a predetermined angle relative to the first face, and a bent portion coupling the first face to the second face. An inner circumferential surface of the rotator slides over the first face. A lateral end accumulation portion and a center accumulation portion are defined by the second face and the bent portion of the nip former and the inner circumferential surface of the rotator. The lateral end accumulation portion is accumulated with a lubricant in a first amount. The center accumulation portion is disposed inboard from the lateral end accumulation portion in an axial direction of the rotator and accumulated with the lubricant in a second amount greater than the first amount.
    Type: Application
    Filed: June 20, 2017
    Publication date: January 18, 2018
    Inventors: Kazunari SAWADA, Ippei FUJIMOTO, Kenji ISHII, Takashi SETO, Hiroshi YOSHINAGA, Takayuki SEKI
  • Publication number: 20180011432
    Abstract: A fixing device includes an endless belt and a pressure rotator disposed opposite an outer circumferential surface of the endless belt. The pressure rotator has a first span in an axial direction of the endless belt. A nip formation pad, which is disposed opposite an inner circumferential surface of the endless belt, forms a fixing nip between the endless belt and the pressure rotator. The nip formation pad includes a belt-side thee disposed opposite the endless belt A radiant heater, which is disposed opposite the inner circumferential surface of the endless belt, heats the endless belt. A thermal conduction aid, which contacts the belt-side face of the nip formation pad, conducts heat in the axial direction of the endless belt. The thermal conduction aid has a second span within which the first span of the pressure rotator is provided at the fixing nip.
    Type: Application
    Filed: June 20, 2017
    Publication date: January 11, 2018
    Inventors: HIROSHI YOSHINAGA, KENJI ISHII, IPPEI FUJIMOTO, TAKASHI SETO, TAKAYUKI SEKI, KAZUNARI SAWADA, RYOHEI MATSUDA
  • Patent number: 9851667
    Abstract: A fixing device includes an endless belt, a nip formation pad disposed inside a loop formed by the endless belt, and a radiant heater to heat the endless belt. A contact heater is disposed at least at one lateral end of the nip formation pad in a longitudinal direction of the nip formation pad. The contact heater includes a heat generator to heat at least one lateral end of the endless belt in an axial direction of the endless belt. A thermal conduction aid, covering a nip-side face of the nip formation pad and a nip-side face of the contact heater, conducts heat applied to the endless belt in the axial direction of the endless belt. The thermal conduction aid includes a heater-side face being disposed opposite the contact heater and covering at least the heat generator of the contact heater.
    Type: Grant
    Filed: December 14, 2016
    Date of Patent: December 26, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Takayuki Seki, Kenji Ishii, Kazuhito Kishi, Takashi Seto, Hiroshi Yoshinaga, Ippei Fujimoto, Kazunari Sawada
  • Patent number: 9851663
    Abstract: A fixing device includes a primary heater disposed opposite a fixing rotator to heat a circumferential span of the fixing rotator other than a fixing nip formed between the fixing rotator and a pressure rotator and a secondary heater disposed outboard from the primary heater in an axial direction of the fixing rotator to heat the fixing rotator at the fixing nip. The primary heater and the secondary heater heat a bi-heating span of the fixing rotator in the axial direction thereof. The secondary heater heats a mono-heating span of the fixing rotator in the axial direction thereof and generates a decreased amount of heat to be conducted to the bi-heating span of the fixing rotator. The decreased amount of heat is smaller than an increased amount of heat to be conducted to the mono-heating span of the fixing rotator that is heated by the secondary heater only.
    Type: Grant
    Filed: May 2, 2016
    Date of Patent: December 26, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Shohta Kobashigawa, Kenji Ishii, Kazuhito Kishi, Takayuki Seki, Hiroshi Yoshinaga, Takashi Seto, Hiromasa Takagi, Ippei Fujimoto, Hiroshi Seo, Takamasa Hase, Kazunari Sawada, Yasuhiko Ogino
  • Publication number: 20170364000
    Abstract: A fixing device includes a nip formation pad which is disposed opposite an endless belt and forms a fixing nip between the endless belt and a pressure rotator. A contact heater is disposed at least at one lateral end of the nip formation pad in a longitudinal direction thereof and heats at least one lateral end of the endless belt in an axial direction thereof. A thermal conduction aid contacts a belt-side face of each of the nip formation pad and the contact heater and conducts heat in the axial direction of the endless belt. A cover is disposed outboard from the thermal conduction aid in a longitudinal direction thereof. The cover covers the belt-side face of the contact heater. The contact heater includes a power supply portion disposed outboard from the thermal conduction aid in the longitudinal direction thereof and covered by the cover.
    Type: Application
    Filed: May 24, 2017
    Publication date: December 21, 2017
    Applicant: Ricoh Company, Ltd.
    Inventors: Takayuki Seki, Takashi Seto, Hiroshi Yoshinaga, Kenji Ishii, Ippei Fujimoto, Kazunari Sawada
  • Patent number: 9846397
    Abstract: A fixing device includes an endless belt formed into a loop, a heater to heat the endless belt, a nip formation assembly disposed inside the loop, and a pressure rotator to press against the nip formation assembly to form a fixing nip between the endless belt and the pressure rotator. The nip formation assembly includes a pressure pad and a supplementary thermal conductor to conduct heat from the heater in an axial direction of the endless belt. The supplementary thermal conductor has an edge portion dimensioned to distance the supplementary thermal conductor from the endless belt at an end portion of a face over which the endless belt slides in a longitudinal direction of the supplementary thermal conductor. A distance between the edge portion of the supplementary thermal conductor and the endless belt increases toward an end portion of the endless belt in the axial direction thereof.
    Type: Grant
    Filed: December 12, 2016
    Date of Patent: December 19, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Kazunari Sawada, Kenji Ishii, Kazuhito Kishi, Takayuki Seki, Ippei Fujimoto, Hiroshi Yoshinaga, Takashi Seto
  • Patent number: 9829840
    Abstract: A fixing device includes a nip formation pad that presses against a pressure rotator via an endless belt to form a fixing nip between the belt and the pressure rotator, through which a recording medium bearing a toner image is conveyed. A fixing heater is disposed opposite at least a center span of a conveyance span of the belt in an axial direction thereof where the recording medium is conveyed to heat the belt. A first lateral end heater and a second lateral end heater are mounted on the nip formation pad and disposed opposite a first lateral end span and a second lateral end span of an inner circumferential surface of the belt in the axial direction thereof, respectively, to heat the belt. The second lateral end heater is electrically connected in series to the first lateral end heater.
    Type: Grant
    Filed: February 1, 2016
    Date of Patent: November 28, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Takashi Seto, Kenji Ishii, Susumu Matsusaka, Yasuhiko Ogino, Shohta Kobashigawa, Kazuhito Kishi, Ippei Fujimoto, Kazunari Sawada, Hiroshi Yoshinaga, Hiromasa Takagi, Takamasa Hase, Hiroshi Seo
  • Patent number: 9811031
    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: September 8, 2015
    Date of Patent: November 7, 2017
    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