Patents by Inventor Takamasa Hase

Takamasa Hase 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: 20110222929
    Abstract: A fixing device includes a nip forming member disposed inside a fixing member and pressed against a pressing member via the fixing member to form a nip portion between the pressing member and the fixing member through which a recording medium bearing a toner image passes. A heat generator disposed inside the fixing member heats the fixing member outside the nip portion and has variable heat distribution over a width of the fixing member. A first temperature detector disposed inside the fixing member contacts an end portion of the heat generator in the width direction of the fixing member, opposite a surface facing the fixing member, to detect a temperature of the heat generator. A second temperature detector disposed inside the fixing member contacts a center of an inner circumferential surface of the fixing member in the width direction, to detect the temperature of the fixing member.
    Type: Application
    Filed: February 15, 2011
    Publication date: September 15, 2011
    Inventors: Ippei FUJIMOTO, Hiroshi Yoshinaga, Tetsuo Tokuda, Takamasa Hase, Toshihiko Shimokawa, Kenji Ishii, Yoshiki Yamaguchi, Masaaki Yoshikawa, Naoki Iwaya, Takahiro Imada, Yutaka Ikebuchi, Kenichi Hasegawa, Akira Shinshi
  • Publication number: 20110222931
    Abstract: A fixing device includes a tubular, stationary metal pipe, a heater, a flexible fuser belt, a rotatable pressure member, a fuser pad, and a tubular pipe cover. The heater is disposed adjacent to the metal pipe to heat a circumference thereof. The metal pipe has multiple through-holes provided at least at a circumferential perforated section thereof. The flexible fuser belt is looped for rotation around the metal pipe to transfer heat radially outward from the heated circumference of the metal pipe. The rotatable pressure member extends opposite the metal pipe with the fuser belt interposed between the metal pipe and the pressure member. The fuser pad, accommodated within the metal pipe, held stationary inside the loop of the fuser belt, presses against the pressure member through the fuser belt to form a fixing nip. The tubular pipe cover is fitted around the metal pipe.
    Type: Application
    Filed: February 17, 2011
    Publication date: September 15, 2011
    Inventors: Akira SHINSHI, Masaaki Yoshikawa, Hiroshi Yoshinaga, Kenichi Hasegawa, Kenji Ishii, Naoki Iwaya, Yutaka Ikebuchi, Tetsuo Tokuda, Ippei Fujimoto, Yoshiki Yamaguchi, Takahiro Imada, Takamasa Hase, Toshihiko Shimokawa
  • Publication number: 20110222888
    Abstract: A fixing device includes an endless belt-shaped fixing member to rotate in a predetermined direction, formed in a loop, an inner circumferential face of which is coated with a lubricant; a pressing member contacting an outer circumferential surface of the fixing member, to press against the fixing member; a driver to drive and rotate the pressing member; a contact member provided inside the loop formed by the fixing member and pressed against the pressing member via the fixing member to form a nip between the pressing member and the fixing member; and a heating member to heat the fixing member, provided inside the loop formed by the fixing member. When the fixing device starts up, the pressing member drives and rotates the fixing member less than 360 degrees to move a warmed range of the fixing member heated by the heating member to the nip.
    Type: Application
    Filed: February 24, 2011
    Publication date: September 15, 2011
    Applicant: Ricoh Company, Ltd.
    Inventors: Yutaka Ikebuchi, Masaaki Yoshikawa, Kenji Ishii, Hiroshi Yoshinaga, Naoki Iwaya, Tetsuo Tokuda, Yoshiki Yamaguchi, Ippei Fujimoto, Takuya Seshita, Takahiro Imada, Takamasa Hase, Toshihiko Shimokawa
  • Publication number: 20110222876
    Abstract: A fixing device includes a fixing member, a pressure member, and a damage detecting unit. The fixing member includes a heat-insulating elastic layer, to which a conductive thin-film layer is provided. The pressure member presses against the fixing member to form a fixing nip. The damage detecting unit detects the electric resistance of the thin-film layer. The damage detecting unit detects a change in the electric resistance of the thin-film layer, thereby detecting damage to the fixing member. Depending on the extent of the damage, the condition of conveyance of a recording medium to the fixing nip is changed.
    Type: Application
    Filed: March 8, 2011
    Publication date: September 15, 2011
    Applicant: Ricoh Company, Limited
    Inventors: Shuutaroh Yuasa, Masanao Ehara, Tadashi Ogawa, Satoshi Ueno, Hiroshi Seo, Takamasa Hase
  • Publication number: 20110222875
    Abstract: A fixing unit removably installable in an image forming apparatus includes an endless fixing member; a metal member disposed in proximity to an inner surface of the fixing member; a nip formation member supported by the metal member to slidably contact the fixing member or oppose the fixing member via a slide sheet; a heater to heat the metal member to heat the fixing member; a rotary pressing member to rotate the fixing member, disposed opposite the nip formation member via the fixing member to form a nip between the rotary pressing member and the fixing member; a rotation detector to detect a rotational state of the fixing member. Heating rotation of the fixing member is continuously performed until a predetermined rotational state of the fixing member is obtained, to spread lubricant substantially uniformly at least between the fixing member and the metal member.
    Type: Application
    Filed: March 15, 2011
    Publication date: September 15, 2011
    Inventors: Takahiro Imada, Masaaki Yoshikawa, Kenji Ishii, Akira Shinshi, Hiroshi Yoshinaga, Kenichi Hasegawa, Naoki Iwaya, Yoshiki Yamaguchi, Tetsuo Tokuda, Yutaka Ikebuchi, Takamasa Hase, Ippei Fujimoto, Toshihiko Shimokawa
  • Publication number: 20110217056
    Abstract: A fixing device includes a substantially cylindrical metal member, a heater, an endless, flexible fixing member, a rotary pressing member, a stationary member, a first temperature detector, and a second temperature detector. The first temperature detector is disposed upstream from a nip in a rotation direction of the fixing member to detect a surface temperature of the fixing member. The second temperature detector is disposed downstream from the nip in a rotation direction of the pressing member to detect a surface temperature of the pressing member. When a difference between a surface temperature of the fixing member detected by the first temperature detector and a surface temperature of the pressing member detected by the second temperature detector after a predetermined time has elapsed since the first temperature detector detects the surface temperature of the fixing member is greater than a predetermined threshold, the heater stops heating the metal member.
    Type: Application
    Filed: February 28, 2011
    Publication date: September 8, 2011
    Applicant: Ricoh Company, Ltd.
    Inventors: Hiroshi Yoshinaga, Kenichi Hasegawa, Masaaki Yoshikawa, Kenji Ishii, Akira Shinshi, Naoki Iwaya, Yutaka Ikebuchi, Tetsuo Tokuda, Ippei Fujimoto, Yoshiki Yamaguchi, Takahiro Imada, Takamasa Hase, Toshihiko Shimokawa
  • Publication number: 20110217095
    Abstract: A fixing device includes an endless belt-shaped fixing member; a pressing member; a contact member provided inside the loop formed by the fixing member and pressed against the pressing member via the fixing member to form a nip between the pressing member and the fixing member, a laminated heater facing an inner circumferential face of the fixing member to heat the fixing member, connected to an external power source, and including a heat generation sheet that includes a heat-resistant resin in which conductive particles to receive electricity from the external power source and generate heat are unevenly dispersed throughout the heat-resistant resin to have a dispersal gradient of increasing particle dispersion density from an inner face toward an outer face of the heat generation sheet; and a heater support to support the laminated heater along the inner circumferential face of the fixing member.
    Type: Application
    Filed: February 10, 2011
    Publication date: September 8, 2011
    Inventors: Kenji Ishii, Masaaki Yoshikawa, Yoshiki Yamaguchi, Toshihiko Shimokawa, Naoki Iwaya, Takahiro Imada, Yutaka Ikebuchi, Takamasa Hase, Tetsuo Tokuda, Hiroshi Yoshinaga, Kenichi Hasegawa, Ippei Fujimoto, Akira Shinshi
  • Publication number: 20110217093
    Abstract: A fixing device includes a fixing member formed into a loop inside which a nip formation member, a core holder, a heater support, and a laminated heater are provided, and a pressing member provided outside the loop formed by the fixing member. The pressing member is pressed against the nip formation member via the fixing member. The heater support is between the laminated heater and the nip formation member to support the laminated heater. The core holder is between the nip formation member and the heater support to support the nip formation member and the heater support.
    Type: Application
    Filed: January 28, 2011
    Publication date: September 8, 2011
    Inventors: Tetsuo TOKUDA, Masaaki Yoshikawa, Kenji Ishii, Hiroshi Yoshinaga, Naoki Iwaya, Yoshiki Yamaguchi, Yutaka Ikebuchi, Takahiro Imada, Takamasa Hase, Ippei Fujimoto, Toshihiko Shimokawa
  • Publication number: 20110206427
    Abstract: A fixing device includes an endless fuser belt, a contact member, a pressure member, a heater, a heater support, and a belt tensioner. The endless fuser belt is looped into a generally cylindrical configuration extending in an axial direction thereof. The contact member extends in the axial direction inside the loop of the fuser belt. The pressure member extends in the axial direction with the belt interposed between the contact member and the pressure member. The pressure member is pressed against the contact member through the fuser belt to form a fixing nip. The heater is disposed inside the loop of the fuser belt to heat the fuser belt. The heater support is disposed inside the loop of the fuser belt to hold the heater in position. The belt tensioner is disposed inside the loop of the fuser belt to tighten the fuser belt.
    Type: Application
    Filed: January 28, 2011
    Publication date: August 25, 2011
    Applicant: Ricoh Company, Ltd.
    Inventors: Naoki Iwaya, Masaaki Yoshikawa, Kenji Ishii, Hiroshi Yoshinaga, Tetsuo Tokuda, Yoshiki Yamaguchi, Ippei Fujimoto, Yutaka Ikebuchi, Takahiro Imada, Takamasa Hase, Toshihiko Shimokawa
  • Publication number: 20110200368
    Abstract: A fixing device includes a contact member provided inside a fixing member and pressed against a pressing member via the fixing member to form a nip between the pressing member and the fixing member through which a recording medium bearing atoner image passes. A sheet heat generator provided in the fixing member includes a flexible heat generation sheet contactable against the fixing member to heat the fixing member. A contact adjuster provided in the fixing member adjusts an area of contact of the heat generation sheet and the fixing member in the axial direction, supports the heat generation sheet at a first position at which the heat generation sheet contacts the fixing member, and bends a portion of the heat generation sheet at a second position to separate the heat generation sheet from the fixing member.
    Type: Application
    Filed: January 19, 2011
    Publication date: August 18, 2011
    Inventors: Yoshiki YAMAGUCHI, Masaaki Yoshikawa, Kenji Ishii, Naoki Iwaya, Tetsuo Tokuda, Yutaka Ikebuchi, Takahiro Imada, Takamasa Hase, Toshihiko Shimokawa, Hiroshi Yoshinaga, Ippei Fujimoto
  • Publication number: 20110200370
    Abstract: A fixing device includes a substantially cylindrical metal member, a heater positioned to heat the metal member, an endless, flexible fixing member disposed rotatably around the metal member and heated by the metal member to heat and fix a toner image, a rotary pressing member disposed opposite the metal member and pressed against an outer circumferential surface of the fixing member to form a nip therebetween, and a stationary member disposed at an inner circumferential surface side of the fixing member and pressed by the pressing member via the fixing member to form the nip. At least when the fixing member is relatively moved toward the metal member during assembly of the fixing member with the metal member, the metal member includes at least one protruding portion protruding axially outward from an axial end of the metal member to guide the fixing member axially toward the metal member.
    Type: Application
    Filed: February 15, 2011
    Publication date: August 18, 2011
    Inventors: Yutaka IKEBUCHI, Hiroshi Yoshinaga, Toshihiko Shimokawa, Masaaki Yoshikawa, Yoshiki Yamaguchi, Naoki Iwaya, Tetsuo Tokuda, Kenji Ishii, Ippei Fujimoto, Shuntaroh Tamaki, Akira Shinshi, Takahiro Imada, Takamasa Hase, Kenichi Hasegawa
  • Publication number: 20110194870
    Abstract: A fixing device includes an endless, fuser belt, a contact member, a pressure member, a heater, a first thermometer, a second thermometer, and a controller. The fuser belt is looped into a generally cylindrical configuration. The contact member extends inside the loop of endless belt. The pressure member extends with the belt interposed between the contact member and the pressure member. The pressure member is pressed against the contact member through the fuser belt to form a fixing nip. The heater includes a first heating element and a second heating element. The first heating element heats the fuser belt at a first position. The second heating element heats the fuser belt at a second position. The first thermometer detects a first temperature of the fuser belt. The second thermometer detects a second temperature of the fuser belt. The controller controls each of the first and second heating elements.
    Type: Application
    Filed: February 3, 2011
    Publication date: August 11, 2011
    Inventors: Takamasa HASE, Kenji Ishii, Masaaki Yoshikawa, Tetsuo Tokuda, Naoki Iwaya, Yoshiki Yamaguchi, Yutaka Ikebuchi, Takahiro Imada, Toshihiko Shimokawa, Hiroshi Yoshinaga, Ippei Fujimoto
  • Publication number: 20110194869
    Abstract: A fixing device includes a substantially cylindrical metal member, a heater, an endless, flexible fixing member, a rotary pressing member, and a stationary member. The heater heats the metal member. The fixing member is disposed rotatable around the metal member. An inner circumferential surface of the fixing member is heated by the metal member to heat and fix a toner image. The rotary pressing member is disposed opposite the metal member and pressed against an outer circumferential surface of the fixing member to form a nip between the rotary pressing member and the fixing member through which a recording medium bearing the toner image passes. The stationary member is disposed in pressure contact with the inner circumferential surface of the fixing member, and has an opposing face opposing the rotary pressing member and having a curvature smaller than a curvature of the rotary pressing member.
    Type: Application
    Filed: February 4, 2011
    Publication date: August 11, 2011
    Applicant: Ricoh Company, Ltd.
    Inventors: Hiroshi Yoshinaga, Masaaki Yoshikawa, Kenichi Hasegawa, Kenji Ishii, Akira Shinshi, Naoki Iwaya, Yutaka Ikebuchi, Ippei Fujimoto, Yoshiki Yamaguchi, Shuntaroh Tamaki, Tetsuo Tokuda, Takamasa Hase, Takahiro Imada, Toshihiko Shimokawa
  • Publication number: 20110182638
    Abstract: A heat conduction unit includes a flexible endless belt, a heat conductor disposed in proximity to an inner circumferential face of the endless belt and having a cross-section substantially identical to a cross-section of the endless belt, a heat source that heats the heat conductor to heat the endless belt, a pressing roller disposed opposite the heat conductor to rotate the endless belt in accordance with rotation of the pressing roller, a nip formation member disposed opposite the pressing roller and within a loop formed by the endless belt to form a nip between the endless belt and the pressing roller, and a pushing member disposed within the loop to support the nip formation member. The heat conductor has at least two different cross-sectional shapes perpendicular to a long direction of the heat conductor at different positions in the long direction of the heat conductor.
    Type: Application
    Filed: January 26, 2011
    Publication date: July 28, 2011
    Inventors: Kenji ISHII, Masaaki Yoshikawa, Tetsuo Tokuda, Yoshiki Yamaguchi, Kenichi Hasegawa, Yutaka Ikebuchi, Akira Shinshi, Naoki Iwaya, Takamasa Hase, Takahiro Imada, Toshihiko Shimokawa, Ippei Fujimoto, Hiroshi Yoshinaga, Shuntaroh Tamaki
  • Publication number: 20110176821
    Abstract: A fixing device, in which an unfixed image carried by a recording medium is passed through a fixing nip part being pressed by a fixing rotative body and a pressuring rotative body, and is fixed to the recording medium, is disclosed, including: a pressing part, and control part. The pressing part applies a pressure to the fixing nip part. The control part controls the pressure to be applied to the fixing nip part by the pressing part, to be lower than a case in which the recording medium passes through a curl correcting part for correcting a curl of the recording medium, when the recording medium does not pass through the curl correcting part.
    Type: Application
    Filed: January 6, 2011
    Publication date: July 21, 2011
    Inventor: Takamasa HASE
  • Patent number: 7983582
    Abstract: An image forming apparatus includes an image carrier, a developing unit, a transfer unit, and a fixer to fix an image formed on a sheet and includes a rotary heat generator including a heat generation layer, a pressure member to form a nip with the rotary heat generator to sandwich the sheet therebetween, an excitation coil disposed facing the rotary heat generator, to inductively heat the heat generation layer, a demagnetization coil disposed facing the heat generation layer, to generate magnetic flux that partly counteracts magnetic flux generated by the excitation coil and a fixer controller to control activation of the excitation coil as well as the demagnetization coil before a second image formation job after completion of a first image formation job in which an image is formed on a sheet of recording media whose width is smaller than a maximum sheet width usable in the fixer.
    Type: Grant
    Filed: May 29, 2009
    Date of Patent: July 19, 2011
    Assignee: Ricoh Company, Limited
    Inventor: Takamasa Hase
  • Publication number: 20110150518
    Abstract: The fixing device using an electromagnetic induction heating (IH) method includes a fixing sleeve having a heating layer, a pressure roller to form a nip while contacting the fixing roller and rotate to drive the fixing sleeve, a temperature detector to detect a temperature on a circumference of the fixing sleeve, and an excitation coil provided near the fixing sleeve and configured to perform induction heating of the heating layer of the fixing sleeve based on the detection result from the temperature detector. The fixing device is configured to change a rotation speed of the fixing sleeve in a standby time during which the fixing sleeve, while rotating, is controlled to be heated so as to maintain a target temperature when a periodic temperature difference occurs on a circumference of the fixing rotary member and having a fluctuation amplitude larger than a predetermined value compared to the target temperature.
    Type: Application
    Filed: December 21, 2010
    Publication date: June 23, 2011
    Inventors: Takamasa HASE, Masanao Ehara, Kenji Ishii, Tadashi Ogawa, Satoshi Ueno, Hiroshi Seo, Takahiro Imada, Shuutaroh Yuasa
  • Publication number: 20110129268
    Abstract: A fixing device includes a pressing member pressed against a fixing member to form a nip between the pressing member and the fixing member through which a recording medium bearing a toner image passes. A heater support provided inside the fixing member supports a laminated heater. The laminated heater is provided between the fixing member and the heater support and includes a flexible, first heat generation sheet that includes an insulating base layer, at least one resistant heat generation layer provided on the base layer to generate heat, and at least one electrode layer provided on the base layer to supply power to the at least one resistant heat generation layer.
    Type: Application
    Filed: November 15, 2010
    Publication date: June 2, 2011
    Inventors: Kenji ISHII, Masaaki Yoshikawa, Hiroshi Yoshinaga, Naoki Iwaya, Yoshiki Yamaguchi, Yutaka Ikebuchii, Tetsuo Tokuda, Takahiro Imada, Takamasa Hase, Toshihiko Shimokawa, Ippei Fujimoto
  • Publication number: 20110116848
    Abstract: A fixing device includes an endless belt, a fuser pad, a pressure member, a tubular belt holder, and a reinforcing member. The endless belt is looped into a generally cylindrical configuration extending in an axial direction. The fuser pad extends in the axial direction inside the loop of endless belt. The pressure member extends in the axial direction with the belt interposed between the fuser pad and the pressure member. The pressure member is pressed against the fuser pad through the fuser belt to form a fixing nip. The belt holder extends in the axial direction inside the loop of endless belt to retain the belt in shape along an outer circumference thereof. The belt holder accommodates the fuser pad in a longitudinal side slot defined on one side thereof. The reinforcing member is disposed inside the tubular belt holder to reinforce the belt holder around the side slot.
    Type: Application
    Filed: November 15, 2010
    Publication date: May 19, 2011
    Inventors: Yoshiki YAMAGUCHI, Masaaki Yoshikawa, Kenji Ishii, Hiroshi Yoshinaga, Naoki Iwaya, Tetsuo Tokuda, Yutaka Ikebuchi, Takahiro Imada, Takamasa Hase, Toshihiko Shimokawa, Kenichi Hasegawa, Akira Shinshi, Ippei Fujimoto
  • Publication number: 20110085832
    Abstract: A fixing device includes a stationary at least partially tubular thermal member, a flexible fuser belt, a fuser pad, and a rotatable pressure member. The thermal member has a tubular portion thereof extending in an axial direction and defining a closed axial cross-section. A circumference of the thermal member is subjected to heating. The fuser belt is looped for rotation around the thermal member. An inner circumference of the fuser belt at least partially faces the thermal member. The fuser pad is held stationary inside the loop of the fuser belt. The pressure member extends opposite the thermal member in the axial direction with the fuser belt interposed between the fuser pad and the pressure member. The fuser pad is pressed against the pressure member through the fuser belt to form a fixing nip. The thermal member is spaced apart from the fuser pad.
    Type: Application
    Filed: September 29, 2010
    Publication date: April 14, 2011
    Inventors: Kenichi HASEGAWA, Masaaki Yoshikawa, Akira Shinshi, Kenji Ishii, Hiroshi Yoshinaga, Yoshiki Yamaguchi, Naoki Iwaya, Tetsuo Tokuda, Yutaka Ikebuchi, Toshihiko Shimokawa, Shuntaroh Tamaki, Takamasa Hase, Ippei Fujimoto, Takahiro Imada