Patents by Inventor Tetsuo Tokuda

Tetsuo Tokuda 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: 20120051774
    Abstract: An image forming apparatus includes a fixing device including a fixing member; a pressure member to press against the fixing member; and a halogen lamp to heat the fixing member, and a controller to control the halogen lamp. The controller controls an ON duty of the halogen lamp according to a control cycle, and sets the ON duty including two thresholds consisting of a first ON duty and a second ON duty that is larger than the first ON duty. The controller calculates an ON duty of the halogen lamp, judges whether the calculated ON duty is equal to or more than the first duty and less then the second duty, and changes the calculated ON duty when the calculated ON duty is equal to or more than the first duty and less then the second duty.
    Type: Application
    Filed: August 25, 2011
    Publication date: March 1, 2012
    Inventors: Yutaka IKEBUCHI, Yoshiki Yamaguchi, Toshihiko Shimokawa, Kenji Ishii, Naoki Iwaya, Takahiro Imada, Tetsuo Tokuda, Takamasa Hase, Hiroshi Yoshinaga, Ippei Fujimoto, Masaaki Yoshikawa
  • Publication number: 20110274453
    Abstract: A fixing device includes a metal thermal conductor provided inside a loop formed by a fixing rotary body to heat the fixing rotary body; a heater provided inside the metal thermal conductor to heat the metal thermal conductor; a pad support provided inside the metal thermal conductor; and a reflector provided between the heater and the pad support to reflect heat emitted by the heater thereto toward an inner circumferential surface of the metal thermal conductor. The reflector includes a center reflection portion provided at a center of the reflector in a longitudinal direction thereof and a plurality of end reflection portions provided at respective lateral ends of the reflector. A plurality of reflector moving assemblies is connected to the plurality of end reflection portions of the reflector, respectively, to tilt the plurality of end reflection portions toward the center reflection portion.
    Type: Application
    Filed: April 29, 2011
    Publication date: November 10, 2011
    Inventors: Toshihiko Shimokawa, Masaaki Yoshikawa, Kenji Ishii, Naoki Iwaya, Tetsuo Tokuda, Yoshiki Yamaguchi, Yutaka Ikebuchi, Takamasa Hase, Takahiro Imada, Akira Shinshi, Kenichi Hasegawa, Hiroshi Yoshinaga, Ippei Fujimoto
  • Publication number: 20110229228
    Abstract: A fixing device includes a tubular belt holder, a rotatable flexible fuser belt, a contact member, a pressure member, and a heater. The tubular belt holder extends in an axial direction thereof. The fuser belt is looped into a generally cylindrical configuration around the belt holder. The tubular belt holder retains the fuser belt in shape as the belt rotates in a circumferential direction. The contact member extends in the axial direction. The pressure member extends in the axial direction. The pressure member presses against the contact member through the fuser belt to form a fixing nip. The heater is disposed to heat a predetermined circumferential portion of the fuser belt. The belt holder includes a first circumferential section and a second circumferential section. The first circumferential section faces the heated portion. The second circumferential section faces upstream from the heated portion in the circumferential direction.
    Type: Application
    Filed: March 10, 2011
    Publication date: September 22, 2011
    Inventors: Masaaki YOSHIKAWA, Yoshiki Yamaguchi, Toshihiko Shimokawa, Kenji Ishii, Naoki Iwaya, Takahiro Imada, Yutaka Ikebuchi, Tetsuo Tokuda, Takamasa Hase, Hiroshi Yoshinaga, Ippei Fujimoto
  • Publication number: 20110229181
    Abstract: A fixing device for fixing a toner image on a recording medium includes a pressing member provided outside a loop formed by a fixing member to press the fixing member against a nip formation member provided inside the loop formed by the fixing member. A heat generator support is provided inside the loop formed by the fixing member to support a heat generator that generates heat to be transmitted to the fixing member. A temperature detector is provided downstream from the heat generator and upstream from the nip formation member in a direction of rotation of the fixing member to detect a temperature of the fixing member. A controller is connected to the temperature detector and the heat generator to control heat generation of the heat generator based on the temperature of the fixing member detected by the temperature detector.
    Type: Application
    Filed: March 7, 2011
    Publication date: September 22, 2011
    Inventors: Naoki Iwaya, Masaaki Yoshikawa, Kenji Ishii, Hiroshi Yoshinaga, Tetsuo Tokuda, Yoshiki Yamaguchi, Yutaka Ikebuchi, Ippei Fujimoto, Takuya Seshita, Takahiro Imada, Takamasa Hase, Toshihiko Shimokawa
  • Publication number: 20110229226
    Abstract: A fixing device includes a fixing member formed into a loop and rotatable in a predetermined direction of rotation. A heating assembly faces a first region on an inner circumferential surface of the fixing member to heat the fixing member. The heating assembly is thermally deformed to contact and move the fixing member. A first fixing member support and a second fixing member support face a second region on the inner circumferential surface of the fixing member other than the first region. The first fixing member support and the second fixing member support contact and support the rotating fixing member moved by the thermally deformed heating assembly.
    Type: Application
    Filed: March 8, 2011
    Publication date: September 22, 2011
    Inventors: Tetsuo TOKUDA, Masaaki YOSHIKAWA, Kenji ISHII, Hiroshi YOSHINAGA, Naoki IWAYA, Yoshiki YAMAGUCHI, Yutaka IKEBUCHI, Ippei FUJIMOTO, Takuya SESHITA, Takahiro IMADA, Takamasa HASE, Toshihiko SHIMOKAWA
  • Publication number: 20110229227
    Abstract: A fixing device includes a tubular belt holder, a rotatable flexible fuser belt, a contact member, a pressure member, and a heater. The belt holder extends in an axial direction thereof. The fuser belt is looped around the belt holder extending in the axial direction. The contact member has a central axis thereof extending in the axial direction, accommodated in the belt holder. The pressure member has a central axis thereof extending in the axial direction, disposed opposite the belt holder with the fuser belt interposed between the contact member and the pressure member. The pressure member presses against the contact member through the fuser belt to form a fixing nip. The heater is disposed adjacent to the belt holder to heat a circumferential portion of the fuser belt. The belt holder includes a generally semi-cylindrical section to face the heated circumferential portion of the fuser belt.
    Type: Application
    Filed: March 10, 2011
    Publication date: September 22, 2011
    Inventors: Masaaki Yoshikawa, Yoshiki Yamaguchi, Toshihiko Shimokawa, Kenji Ishii, Naoki Iwaya, Takahiro Imada, Yutaka Ikebuchi, Tetsuo Tokuda, Takamasa Hase, Takuya Seshita, Hiroshi Yoshinaga, Ippei Fujimoto
  • Publication number: 20110229225
    Abstract: A fixing device includes an endless belt-shaped fixing member formed into a loop and rotatable in a predetermined direction of rotation, a pressing member contacting an outer circumferential surface of the fixing member, a heater support assembly provided inside the loop formed by the fixing member, and a laminated heater supported by the heater support assembly and provided inside the loop formed by the fixing member. The laminated heater includes an elastic sheet contacting an inner circumferential surface of the fixing member with pressure generated by elasticity of bending of the elastic sheet to heat the fixing member.
    Type: Application
    Filed: February 25, 2011
    Publication date: September 22, 2011
    Applicant: Ricoh Company, Ltd.
    Inventors: Kenji Ishii, Masaaki Yoshikawa, Yoshiki Yamaguchi, Toshihiko Shimokawa, Naoki Iwaya, Takahiro Imada, Yutaka Ikebuchi, Tetsuo Tokuda, Takamasa Hase, Takuya Seshita, Hiroshi Yoshinaga, Ippei Fujimoto
  • 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: 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: 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: 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: 20110222930
    Abstract: A fixing device includes a support member fixedly provided inside a loop formed by a fixing member to support a nip formation member provided inside the loop formed by the fixing member. A biasing member is provided between the support member and a heater support that supports a laminated heater that generates heat to be transmitted to the fixing member. The heater support thermally expands in a first direction due to heat generated by the laminated heater. The biasing member applies bias to the heater support in a second direction opposite the first direction and in which the heater support presses the laminated heater against an inner circumferential surface of the fixing member.
    Type: Application
    Filed: February 16, 2011
    Publication date: September 15, 2011
    Inventors: IPPEI FUJIMOTO, KENJI ISHII, MASAAKI YOSHIKAWA, HIROSHI YOSHINAGA, NAOKI IWAYA, YOSHIKI YAMAGUCHI, YUTAKA IKEBUCHI, TETSUO TOKUDA, TAKAHIRO IMADA, TAKAMASA HASE, TOSHIHIKO SHIMOKAWA, TAKUYA SESHITA
  • 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: 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: 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: 20110211876
    Abstract: A fixing device includes a flexible, endless belt-shaped fixing member that rotates in a predetermined direction of rotation, a substantially cylindrical metal heat conductor provided inside a loop formed by the fixing member and facing an inner circumferential surface of the fixing member, a pressing member that presses the fixing member against the metal heat conductor to form a nip between the fixing member and the pressing member through which a recording medium bearing a toner image passes, and a separator that presses the fixing member against the metal heat conductor, provided downstream from the nip in the direction of rotation of the fixing member and contacting the recording medium discharged from the nip to separate the recording medium from the fixing member and guide the recording medium out of the fixing device.
    Type: Application
    Filed: December 9, 2010
    Publication date: September 1, 2011
    Inventors: Naoki IWAYA, Masaaki Yoshikawa, Akira Shinshi, Kenji Ishii, Kenichi Hasegawa, Hiroshi Yoshinaga, Yoshiki Yamaguchi, Yutaka Ikebuchi, Ippei Fujimoto, Shuntaroh Tamaki, Toshihiko Shimokawa, Tetsuo Tokuda
  • 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: 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: 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: 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