Patents by Inventor Keitaro SHOJI

Keitaro SHOJI 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: 20190094764
    Abstract: A fixing device includes a fixing rotator being rotatable and a heater to heat the fixing rotator. The heater includes a tube, a heat generator, disposed inside the tube, to generate heat, and a sealing portion, disposed at each lateral end of the tube in a longitudinal direction of the heater, to seal the tube. A reflector reflects heat radiated from the heater toward the fixing rotator. The reflector includes an outboard edge being disposed inboard from at least a part of the sealing portion in an axial direction of the fixing rotator.
    Type: Application
    Filed: November 9, 2018
    Publication date: March 28, 2019
    Inventors: Yasunori ISHIGAYA, Kazuya SAITO, Keitaro SHOJI, Toshihiko SHIMOKAWA, Hiromasa TAKAGI
  • Patent number: 10156818
    Abstract: A fixing device includes a fixing rotator being rotatable and a heater to heat the fixing rotator. The heater includes a tube, a heat generator, disposed inside the tube, to generate heat, and a sealing portion, disposed at each lateral end of the tube in a longitudinal direction of the heater, to seal the tube. The sealing portion includes an inboard edge. A reflector reflects heat radiated from the heater toward the fixing rotator. The reflector includes an outboard edge being disposed inboard from the inboard edge of the sealing portion in an axial direction of the fixing rotator.
    Type: Grant
    Filed: January 19, 2017
    Date of Patent: December 18, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Yasunori Ishigaya, Kazuya Saito, Keitaro Shoji, Toshihiko Shimokawa, Hiromasa Takagi
  • Patent number: 10152006
    Abstract: A fixing device includes a rotatable endless belt formed into a loop and a heater disposed opposite the endless belt to heat the endless belt. A nip formation pad is disposed inside the loop formed by the endless belt. The nip formation pad includes a metallic thermal equalizer extending in an axial direction of the endless belt. A rotatable pressure rotator presses against the nip formation pad via the endless belt to form a fixing nip between the endless belt and the pressure rotator, through which a recording medium bearing a toner image is conveyed. The pressure rotator includes an increased tackiness portion disposed at a lateral end of the pressure rotator in an axial direction of the pressure rotator to transmit a driving force to the endless belt. The increased tackiness portion is disposed opposite the thermal equalizer of the nip formation pad.
    Type: Grant
    Filed: May 20, 2016
    Date of Patent: December 11, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Yasunori Ishigaya, Yutaka Ikebuchi, Kazuya Saito, Keitaro Shoji, Ryohei Matsuda, Hiromasa Takagi, Ryuuichi Mimbu, Toshihiko Shimokawa
  • Patent number: 10067449
    Abstract: A fixing device includes a primary heater and a secondary heater that heat a fixing rotator. The primary heater includes a primary major heat generation portion and a primary minor heat generation portion. The primary minor heat generation portion includes a major heat generator that generates an increased amount of heat and a minor heat generator that generates a decreased amount of heat smaller than the increased amount of heat generated by the major heat generator. The major heat generator has a width in an axial direction of the fixing rotator that is not smaller than 30 percent and not greater than 35 percent with respect to a width of the primary minor heat generation portion in the axial direction of the fixing rotator. A temperature detector is disposed opposite the minor heat generator of the primary heater to detect a temperature of the fixing rotator.
    Type: Grant
    Filed: June 27, 2016
    Date of Patent: September 4, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Ryohei Matsuda, Yutaka Ikebuchi, Yasunori Ishigaya, Kazuya Saito, Keitaro Shoji
  • Patent number: 10061235
    Abstract: A fixing device includes an endless fixing belt that is multilayered, an opposing rotator disposed opposite the fixing belt and pressed to the fixing belt to form a nip, a heater disposed inside the fixing belt, and a safety device including a contactless temperature sensor disposed outside the fixing belt and apart from an outer face of the fixing. The fixing belt is to rotate and thermally expand. The contactless temperature sensor detects a temperature of the fixing belt. The safety device stops heating by the heater when the temperature detected by the contactless temperature sensor is at or higher than a predetermined temperature. As the outer face of the fixing belt shifts outward in the radial direction due to thermal, a proportion of the outer face of the fixing belt in a viewing angle of the contactless temperature sensor increases.
    Type: Grant
    Filed: December 30, 2016
    Date of Patent: August 28, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Keitaro Shoji, Yasunori Ishigaya, Kazuya Saito, Ryohei Matsuda, Hiromasa Takagi, Ryuuichi Mimbu, Toshihiko Shimokawa
  • Patent number: 10012932
    Abstract: An image forming apparatus includes a fixing device to fix a toner image onto a recording medium, a voltmeter to measure an input voltage from an external source, and a controller operatively connected to the fixing device and the voltmeter. The fixing device includes an endless, fixing rotator formed into a loop, a heater to heat the fixing rotator, a pressure pad disposed inside the loop, and a pressure rotator disposed opposite the pressure pad via the fixing rotator to press the fixing rotator against the pressure pad to form a fixing nip between the fixing rotator and the pressure rotator, through which the recording medium bearing the toner image is conveyed. The controller controls a heating operation of the heater and a fixing operation of the fixing device to fix the toner image onto the recording medium, based on the input voltage measured by the voltmeter.
    Type: Grant
    Filed: January 9, 2017
    Date of Patent: July 3, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Yasunori Ishigaya, Ryuuichi Mimbu, Hiromasa Takagi, Toshihiko Shimokawa, Kazuya Saito, Keitaro Shoji
  • Patent number: 9904220
    Abstract: A fixing device includes a fixing belt and an opposed rotator to press against a nip formation pad via the fixing belt to form a fixing nip between the fixing belt and the opposed rotator. A primary heater and a secondary heater heat the fixing belt. The secondary heater includes a lateral end heat generator. The nip formation pad includes a base and at least one thermal conductor being interposed between the base and the fixing nip and having a thermal conductivity greater than a thermal conductivity of the base. The at least one thermal conductor includes an outboard edge disposed between an inboard edge and an outboard edge of the lateral end heat generator and disposed outboard from a conveyance span of the fixing belt in an axial direction of the fixing belt, where a recording medium is conveyed over the fixing belt.
    Type: Grant
    Filed: February 16, 2017
    Date of Patent: February 27, 2018
    Assignee: Ricoh Company, Ltd.
    Inventors: Kazuya Saito, Yasunori Ishigaya, Keitaro Shoji, Hiromasa Takagi, Toshihiko Shimokawa
  • Patent number: 9804546
    Abstract: A fixing device includes a primary heat generator and a secondary heat generator to heat an endless belt and a temperature detector, disposed opposite the secondary heat generator, to detect a temperature of the endless belt. The secondary heat generator includes an inboard edge and an outboard edge disposed outboard from the inboard edge in an axial direction of the endless belt. The secondary heat generator has an inboard length defined between a center of a detection span of the temperature detector and the inboard edge in the axial direction of the endless belt. The secondary heat generator further has an outboard length defined between the center of the detection span of the temperature detector and the outboard edge in the axial direction of the endless belt. The secondary heat generator defines a ratio of the outboard length to the inboard length that is greater than 7/3.
    Type: Grant
    Filed: July 6, 2016
    Date of Patent: October 31, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Kazuya Saito, Yasunori Ishigaya, Yutaka Ikebuchi, Keitaro Shoji, Ryohei Matsuda
  • Publication number: 20170255149
    Abstract: A nip-forming member includes: a first nip-forming member configured to be a main body of the nip-forming member; and a second nip-forming member disposed on a surface of the first nip-forming member, the surface facing the inner circumferential surface, the second nip-forming member extending in a direction orthogonal to a rotating direction of the fixing belt. Both ends of the second nip-forming member on an upstream side and a downstream side of the rotating direction are bent in a direction away from the nipping part, in order to create a pair of side-wall portions, so that the second nip-forming member has a concave cross-section for accommodating the first nip-forming member. The second nip-forming member has a restraining portion at a position located on the side-wall portion created on the upstream side, the restraining portion being configured to restrain the first nip-forming member not to be detached from the concave cross-section.
    Type: Application
    Filed: February 15, 2017
    Publication date: September 7, 2017
    Inventors: Hiromasa TAKAGI, Yasunori ISHIGAYA, Kazuya SAITO, Toshihiko SHIMOKAWA, Keitaro SHOJI
  • Patent number: 9753417
    Abstract: A fixing device includes an endless fixing belt; a pressure roller to contact the fixing belt; a nip forming member to press the pressure roller from the fixing belt; a nip portion formed between the fixing belt and the pressure roller; a heater to heat the fixing belt to fuse and fix toner onto a recording sheet in the nip portion; an auxiliary driven roller; an auxiliary drive roller to drive the driven roller; an auxiliary nip portion, formed between an outer circumferential surface of the auxiliary driven roller and an outer circumferential surface of the auxiliary drive roller, to nip the recording sheet after toner fixation conveyed from the nip portion; and an outlet guide member, disposed downstream of the auxiliary nip portion, to guide the recording sheet after toner fixation conveyed from the auxiliary nip portion, with the toner-fixed recording sheet surface bent in a concave shape.
    Type: Grant
    Filed: March 15, 2016
    Date of Patent: September 5, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Yoshiki Yamaguchi, Yoshio Hattori, Haruyuki Honda, Ryuuichi Mimbu, Toshihiko Shimokawa, Yutaka Ikebuchi, Yasunori Ishigaya, Kazuya Saito, Keitaro Shoji, Ryohei Matsuda
  • Publication number: 20170248885
    Abstract: A fixing device includes a fixing belt and an opposed rotator to press against a nip formation pad via the fixing belt to form a fixing nip between the fixing belt and the opposed rotator. A primary heater and a secondary heater heat the fixing belt. The secondary heater includes a lateral end heat generator. The nip formation pad includes a base and at least one thermal conductor being interposed between the base and the fixing nip and having a thermal conductivity greater than a thermal conductivity of the base. The at least one thermal conductor includes an outboard edge disposed between an inboard edge and an outboard edge of the lateral end heat generator and disposed outboard from a conveyance span of the fixing belt in an axial direction of the fixing belt, where a recording medium is conveyed over the fixing belt.
    Type: Application
    Filed: February 16, 2017
    Publication date: August 31, 2017
    Inventors: Kazuya Saito, Yasunori Ishigaya, Keitaro Shoji, Hiromasa Takagi, Toshihiko Shimokawa
  • Publication number: 20170248879
    Abstract: A fixing device includes a fixing rotator being rotatable and a heater to heat the fixing rotator. The heater includes a tube, a heat generator, disposed inside the tube, to generate heat, and a sealing portion, disposed at each lateral end of the tube in a longitudinal direction of the heater, to seal the tube. The sealing portion includes an inboard edge. A reflector reflects heat radiated from the heater toward the fixing rotator. The reflector includes an outboard edge being disposed inboard from the inboard edge of the sealing portion in an axial direction of the fixing rotator.
    Type: Application
    Filed: January 19, 2017
    Publication date: August 31, 2017
    Inventors: Yasunori ISHIGAYA, Kazuya SAITO, Keitaro SHOJI, Toshihiko SHIMOKAWA, Hiromasa TAKAGI
  • Publication number: 20170212457
    Abstract: An image forming apparatus includes a fixing device to fix a toner image onto a recording medium, a voltmeter to measure an input voltage from an external source, and a controller operatively connected to the fixing device and the voltmeter. The fixing device includes an endless, fixing rotator formed into a loop, a heater to heat the fixing rotator, a pressure pad disposed inside the loop, and a pressure rotator disposed opposite the pressure pad via the fixing rotator to press the fixing rotator against the pressure pad to form a fixing nip between the fixing rotator and the pressure rotator, through which the recording medium bearing the toner image is conveyed. The controller controls a heating operation of the heater and a fixing operation of the fixing device to fix the toner image onto the recording medium, based on the input voltage measured by the voltmeter.
    Type: Application
    Filed: January 9, 2017
    Publication date: July 27, 2017
    Inventors: Yasunori ISHIGAYA, Ryuuichi MIMBU, Hiromasa TAKAGI, Toshihiko SHIMOKAWA, Kazuya SAITO, Keitaro SHOJI
  • Publication number: 20170205742
    Abstract: A fixing device includes an endless fixing belt that is multilayered, an opposing rotator disposed opposite the fixing belt and pressed to the fixing belt to form a nip, a heater disposed inside the fixing belt, and a safety device including a contactless temperature sensor disposed outside the fixing belt and apart from an outer face of the fixing. The fixing belt is to rotate and thermally expand. The contactless temperature sensor detects a temperature of the fixing belt. The safety device stops heating by the heater when the temperature detected by the contactless temperature sensor is at or higher than a predetermined temperature. As the outer face of the fixing belt shifts outward in the radial direction due to thermal, a proportion of the outer face of the fixing belt in a viewing angle of the contactless temperature sensor increases.
    Type: Application
    Filed: December 30, 2016
    Publication date: July 20, 2017
    Inventors: Keitaro SHOJI, Yasunori ISHIGAYA, Kazuya SAITO, Ryohei MATSUDA, Hiromasa TAKAGI, Ryuuichi MIMBU, Toshihiko SHIMOKAWA
  • Patent number: 9618888
    Abstract: A fixing device includes a fixing rotator rotatable in a predetermined direction of rotation and an opposed rotator disposed opposite the fixing rotator to form a fixing nip therebetween through which a recording medium bearing a toner image is conveyed. A heater is disposed opposite the fixing rotator to heat the fixing rotator. A nip formation pad is disposed opposite an inner circumferential surface of the fixing rotator. The nip formation pad includes a base, a first thermal conductor sandwiched between the base and the fixing rotator and having a first thermal conductivity greater than a thermal conductivity of the base, and a bulge projecting from the first thermal conductor toward the opposed rotator at a downstream end of the first thermal conductor in a recording medium conveyance direction.
    Type: Grant
    Filed: February 10, 2016
    Date of Patent: April 11, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Keitaro Shoji, Kenji Ishii, Hiromasa Takagi, Takayuki Seki
  • Patent number: 9599940
    Abstract: A fixing device includes: a fixing member that is rotatable and in an endless shape; a heat source that heats the fixing member; a nip forming member that is arranged inside the fixing member; and a pressurizing member that is pressurized to be in contact with the nip forming member through the fixing member, to form a fixing nip. The fixing device fixes an unfixed image on a recording medium by passing the recording medium that carries the unfixed image through the fixing nip. The nip forming member includes a base layer, and a high thermal-conductive layer that is arranged on a surface layer of the base layer on a fixing nip side, and that has higher thermal conductivity than the base layer, and in the high thermal-conductive layer, a low thermal-conductive portion is arranged near an end portion in an axial direction of the fixing member.
    Type: Grant
    Filed: March 13, 2015
    Date of Patent: March 21, 2017
    Assignee: RICOH COMPANY, LTD.
    Inventors: Motoyoshi Yamano, Kohichi Utsunomiya, Hiromasa Takagi, Kenji Ishii, Takayuki Seki, Keitaro Shoji, Hideo Nagafuji, Yuji Arai, Arinobu Yoshiura, Shohei Saito, Qifeng Cui, Yutaka Ikebuchi
  • Patent number: 9581948
    Abstract: A fixing device includes a fixing rotator and a pressure rotator pressed against a nip formation pad via the fixing rotator to form a fixing nip between the fixing rotator and the pressure rotator, through which a recording medium is conveyed. The nip formation pad includes an increased thermal conduction portion having an increased thermal conductivity and a decreased thermal conduction portion having a decreased thermal conductivity and being inboard from the increased thermal conduction portion in the axial direction of the fixing rotator. The increased thermal conduction portion is disposed opposite a non-conveyance span of the fixing rotator where the recording medium is not conveyed and includes an inboard edge inboard from a lateral edge of the recording medium toward a center of the recording medium in the axial direction of the fixing rotator by a predetermined first distance.
    Type: Grant
    Filed: October 2, 2014
    Date of Patent: February 28, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiromasa Takagi, Kenji Ishii, Takayuki Seki, Keitaro Shoji
  • Patent number: 9575447
    Abstract: A fixing device includes a nip formation pad to form a fixing nip between a first fixing rotator and a second fixing rotator, through which a recording medium bearing a toner image is conveyed. The nip formation pad includes a first planar face, a second planar face disposed downstream from the first planar face in a recording medium conveyance direction and being parallel to the first planar face, and a joint face bridging the first planar face and the second planar face. The joint face includes a first curved portion adjoining the first planar face and having a first curvature in a first direction in which a circumferential face of the second fixing rotator is curved and a second curved portion adjoining the second planar face and having a second curvature in a second direction opposite the first direction.
    Type: Grant
    Filed: January 29, 2016
    Date of Patent: February 21, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Yutaka Ikebuchi, Yasunori Ishigaya, Takuya Seshita, Kazuya Saito, Motoyoshi Yamano, Keitaro Shoji
  • Patent number: 9557697
    Abstract: A recording media smoothness detector includes a sensor and a calculator. The sensor includes a light source to emit light toward a recording medium and a light detector to detect an amount of light reflected by the recording medium. The calculator includes a first memory to store an initial output value of the sensor and a second memory to store a decreased output percentage of the sensor relative to the initial output value per number of recording media detected. The calculator is configured to calculate a decreased output amount of the sensor from the decreased output percentage of the sensor per number of recording media detected, according to a number of recording media detected by the sensor, to adjust a luminosity of the light source based on the calculated decreased output amount of the sensor and determine a type of the recording medium based on an output of the sensor after the adjustment of the luminosity of the light source and based on the number of recording media detected by the sensor.
    Type: Grant
    Filed: March 10, 2015
    Date of Patent: January 31, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Takumi Waida, Shuji Hirai, Terumichi Ochi, Shinji Kato, Ryota Yamashina, Keitaro Shoji
  • Publication number: 20170017182
    Abstract: A fixing device includes a primary heat generator and a secondary heat generator to heat an endless belt and a temperature detector, disposed opposite the secondary heat generator, to detect a temperature of the endless belt. The secondary heat generator includes an inboard edge and an outboard edge disposed outboard from the inboard edge in an axial direction of the endless belt. The secondary heat generator has an inboard length defined between a center of a detection span of the temperature detector and the inboard edge in the axial direction of the endless belt. The secondary heat generator further has an outboard length defined between the center of the detection span of the temperature detector and the outboard edge in the axial direction of the endless belt. The secondary heat generator defines a ratio of the outboard length to the inboard length that is greater than 7/3.
    Type: Application
    Filed: July 6, 2016
    Publication date: January 19, 2017
    Inventors: Kazuya SAITO, Yasunori ISHIGAYA, Yutaka IKEBUCHI, Keitaro SHOJI, Ryohei MATSUDA