Patents by Inventor Shigeru Obata

Shigeru Obata 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: 7953361
    Abstract: The fixing device includes a fixing unit, a pressure unit that comes into pressure-contact with the fixing unit to form a nip, and control guides. The fixing unit includes a heat roller. The pressure unit includes a pressure belt, and a pressure pad. The pressure pad is attached to a holder and pressed by a spring through a stay, thereby bringing the pressure belt into pressure-contact with the heat roller. The control guides on both sides of the pressure pad control deformation of the pressure pad in an axial direction of the heat roller to make a nip shape uniform.
    Type: Grant
    Filed: September 19, 2007
    Date of Patent: May 31, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Shigeru Obata, Yoshihiro Fukuhata, Masahiro Yagi, Toshio Ogiso
  • Patent number: 7885591
    Abstract: A low-heat loss, belt nip-type fixing device achieves good recording medium separation performance without increasing the size of the device, prevents image misalignment, and achieves a high-quality image without placing a major burden on the recording medium. This fixing device comprises a heat-fixing roller having an elastic layer and a heat source; and a pressurizing unit having an elastic member with a flat surface for pressing an endless member. The endless member conveys a recording medium, against the elastic layer. A pressurizing spring biases the elastic member toward the side of the recording medium. Biasing is carried out using the pressurizing spring such that the amount of deformation of the elastic member approaches the saturation region (maximum amount of deformation) inside a region of a nip portion, which is formed between the elastic layer of the heat-fixing roller and the endless member of pressurizing unit, and through which is passed a recording medium carrying an unfixed toner image.
    Type: Grant
    Filed: March 14, 2007
    Date of Patent: February 8, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Masahiro Yagi, Yoshihiro Fukuhata, Shigeru Obata
  • Patent number: 7831186
    Abstract: A pressurizing member includes an elastic member having a uniform elastic modulus of K=EA/t, where E is a Young's modulus, A is an area of the nip portion, and t is a thickness of the elastic member in the direction of application of load. A supporting member that supports the pressurizing member has an entering portion, an exit portion, and a center portion between the entering portion and the exit portion. The thickness of the center portion in a direction of application of load is larger than thicknesses of the entering portion and the exit portion in the direction of application of load so that the supporting unit has a convex portion.
    Type: Grant
    Filed: July 12, 2007
    Date of Patent: November 9, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Shigeru Obata, Masahiro Yagi, Yoshihiro Fukuhata, Shin Yamamoto, Toshio Ogiso
  • Patent number: 7761044
    Abstract: A ratio of a radius of curvature of a pressure applying member with an elastic layer, which pushes an endless belt wound around an endless heating member with pressure, in a transferring direction to a radius of curvature of an outer diameter of the heating roller is set to 1.1 or more.
    Type: Grant
    Filed: August 23, 2006
    Date of Patent: July 20, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Masahiro Yagi, Toshio Ogiso, Shigeru Obata, Chikara Hiraoka, Toru Hanashima, Osamu Saito
  • Patent number: 7664447
    Abstract: A fixing device includes a fixing member of which surface is deformable, a heating unit that heats the fixing member, a pressurizing unit having an endless member and a pressurizing member. The pressurizing member includes an elastic layer and presses the endless member against the fixing member to bring the endless member into pressure contact with the fixing member. The elastic layer has an apparent hardness (ASKER-C) which is larger than that at a point where an apparent hardness starts to change rapidly with respect to a rubber thickness in a load application direction.
    Type: Grant
    Filed: August 2, 2007
    Date of Patent: February 16, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Masahiro Yagi, Yoshihiro Fukuhata, Shigeru Obata
  • Patent number: 7433640
    Abstract: In a fixing apparatus including heating member having an elastic layer and a heat source and pressing member having an endless shape member and a pressing member for transporting a record medium in a cut sheet shape while being adhered with an unfixed toner image to pass a nip portion formed by the endless shape member and the heating member and fixing the unfixed toner image on the record medium, the fixing apparatus is constructed by a constitution in which a space between the toner image on the record medium and a surface of the heating member is widened immediately after the record medium is projected from an outlet of the nip portion.
    Type: Grant
    Filed: March 14, 2006
    Date of Patent: October 7, 2008
    Assignee: Ricoh Printing Systems, Ltd.
    Inventors: Masahiro Yagi, Toshio Ogiso, Shunichi Oohara, Shigeru Obata, Toru Hanashima, Osamu Saito
  • Patent number: 7406287
    Abstract: A disclosed fixing device includes: a heat roller unit having a rotatable roller having an elastic body on a surface thereof and a heating unit heating the roller; a pad disposed along a circumference of the elastic body of the heat roller; a belt member disposed on a curved surface of the pad, the belt member rotating by following a rotation of the heat roller; and a pressure member pressing the belt member to the heat roller using the pad, the fixing device causing a conveyed recording medium carrying a visualized image to pass through a space between the heat roller and the pressure member so as to fix the visualized image on the recording medium, wherein a curvature of the curved surface of the pad is changed in a central portion and end portions in an axial direction of the heat roller.
    Type: Grant
    Filed: February 20, 2007
    Date of Patent: July 29, 2008
    Assignee: Ricoh Printing Systems, Ltd.
    Inventors: Hiroyoshi Matsumoto, Toshio Ogiso, Shigeru Obata, Masahiro Yagi, Chikara Hiraoka, Chiharu Kamoshida
  • Publication number: 20080069611
    Abstract: The fixing device includes a fixing unit, a pressure unit that comes into pressure-contact with the fixing unit to form a nip, and control guides. The fixing unit includes a heat roller. The pressure unit includes a pressure belt, and a pressure pad. The pressure pad is attached to a holder and pressed by a spring through a stay, thereby bringing the pressure belt into pressure-contact with the heat roller. The control guides on both sides of the pressure pad control deformation of the pressure pad in an axial direction of the heat roller to make a nip shape uniform.
    Type: Application
    Filed: September 19, 2007
    Publication date: March 20, 2008
    Inventors: Shigeru OBATA, Yoshihiro Fukuhata, Masahiro Yagi, Toshio Ogiso
  • Publication number: 20080031664
    Abstract: A fixing device includes a fixing member of which surface is deformable, a heating unit that heats the fixing member, a pressurizing unit having an endless member and a pressurizing member. The pressurizing member includes an elastic layer and presses the endless member against the fixing member to bring the endless member into pressure contact with the fixing member. The elastic layer has an apparent hardness (ASKER-C) which is larger than that at a point where an apparent hardness starts to change rapidly with respect to a rubber thickness in a load application direction.
    Type: Application
    Filed: August 2, 2007
    Publication date: February 7, 2008
    Inventors: Masahiro YAGI, Yoshihiro Fukuhata, Shigeru Obata
  • Publication number: 20080013993
    Abstract: A pressurizing member includes an elastic member having a uniform elastic modulus of K=EA/t, where E is a Young's modulus, A is an area of the nip portion, and t is a thickness of the elastic member in the direction of application of load. A supporting member that supports the pressurizing member has an entering portion, an exit portion, and a center portion between the entering portion and the exit portion. The thickness of the center portion in a direction of application of load is larger than thicknesses of the entering portion and the exit portion in the direction of application of load so that the supporting unit has a convex portion.
    Type: Application
    Filed: July 12, 2007
    Publication date: January 17, 2008
    Inventors: Shigeru OBATA, Masahiro Yagi, Yoshihiro Fukuhata, Shin Yamamoto, Toshio Ogiso
  • Publication number: 20080013992
    Abstract: A pressurizing unit includes an elastic member that has an entering portion on a side from where a recording medium enters a nip portion, an exit portion on a side from where the recording medium exits the nip portion, and a center portion between the entering portion and the exit portion. The elastic modulus of the center portion is higher than elastic moduli of the entering portion and the exit portion.
    Type: Application
    Filed: June 29, 2007
    Publication date: January 17, 2008
    Inventors: Yoshihiro Fukuhata, Masahiro Yagi, Shigeru Obata
  • Patent number: 7298981
    Abstract: A fixing device includes a first fixing part having a heater disposed therein, a second fixing part, disposed to oppose to the first fixing part, for pinching a recording medium to form a first nip portion, a pair of transfer rollers, disposed at a downstream side of the recording medium, for forming a second nip portion, a guide for biasing the recording medium discharged from the transfer rollers towards the first fixing part side from one of the transfers rollers, and means part for biasing the guide towards the recording medium side.
    Type: Grant
    Filed: July 7, 2005
    Date of Patent: November 20, 2007
    Assignee: Ricoh Printing Systems, Ltd.
    Inventors: Shunichi Oohara, Hiroyuki Seki, Toshio Ogiso, Shigeru Obata, Chikara Hiraoka, Toru Hanashima, Kazuhiro Wakamatsu
  • Publication number: 20070223976
    Abstract: A low-heat loss, belt nip-type fixing device achieves good recording medium separation performance without increasing the size of the device, prevents image misalignment, and achieves a high-quality image without placing a major burden on the recording medium. This fixing device comprises a heat-fixing roller having an elastic layer and a heat source; and a pressurizing unit having an elastic member with a flat surface for pressing an endless member. The endless member conveys a recording medium, against the elastic layer. A pressurizing spring biases the elastic member toward the side of the recording medium. Biasing is carried out using the pressurizing spring such that the amount of deformation of the elastic member approaches the saturation region (maximum amount of deformation) inside a region of a nip portion, which is formed between the elastic layer of the heat-fixing roller and the endless member of pressurizing unit, and through which is passed a recording medium carrying an unfixed toner image.
    Type: Application
    Filed: March 14, 2007
    Publication date: September 27, 2007
    Inventors: Masahiro YAGI, Yoshihiro Fukuhata, Shigeru Obata
  • Publication number: 20070196145
    Abstract: A disclosed fixing device includes: a heat roller unit having a rotatable roller having an elastic body on a surface thereof and a heating unit heating the roller; a pad disposed along a circumference of the elastic body of the heat roller; a belt member disposed on a curved surface of the pad, the belt member rotating by following a rotation of the heat roller; and a pressure member pressing the belt member to the heat roller using the pad, the fixing device causing a conveyed recording medium carrying a visualized image to pass through a space between the heat roller and the pressure member so as to fix the visualized image on the recording medium, wherein a curvature of the curved surface of the pad is changed in a central portion and end portions in an axial direction of the heat roller.
    Type: Application
    Filed: February 20, 2007
    Publication date: August 23, 2007
    Inventors: Hiroyoshi MATSUMOTO, Toshio OGISO, Shigeru OBATA, Masahiro YAGI, Chikara HIRAOKA, Chiharu KAMOSHIDA
  • Publication number: 20070071514
    Abstract: In a fixing apparatus including heating member having an elastic layer and a heat source and pressing member having an endless shape member and a pressing member for transporting a record medium in a cut sheet shape while being adhered with an unfixed toner image to pass a nip portion formed by the endless shape member and the heating member and fixing the unfixed toner image on the record medium, the fixing apparatus is constructed by a constitution in which a space between the toner image on the record medium and a surface of the heating member is widened immediately after the record medium is projected from an outlet of the nip portion.
    Type: Application
    Filed: March 14, 2006
    Publication date: March 29, 2007
    Applicant: RICOH PRINTING SYSTEMS, LTD.
    Inventors: Masahiro Yagi, Toshio Ogiso, Shunichi Oohara, Shigeru Obata, Toru Hanashima, Osamu Saito
  • Publication number: 20070071467
    Abstract: An image formation apparatus is disclosed. The image formation apparatus includes a fixing unit whose heater temperature is controlled to be in a non-offsetting range so that no offset is produced, the non-offsetting range being defined for each different paper thickness. Nip time remains constant even when the thickness of the paper to be printed on next is changed. Printing is suspended until the heater temperature, approaching the non-offsetting range, reaches an inconspicuous offset range on either side of the non-offsetting range, inconspicuous offset being produced if printing is performed in the inconspicuous offset range.
    Type: Application
    Filed: June 28, 2006
    Publication date: March 29, 2007
    Inventors: Teruaki Mitsuya, Masahiro Yagi, Toshio Ogiso, Shunichi Oohara, Shigeru Obata, Toru Hanashima, Osamu Saito
  • Publication number: 20070048045
    Abstract: A ratio of a radius of curvature of a pressure applying member with an elastic layer, which pushes an endless belt wound around an endless heating member with pressure, in a transferring direction to a radius of curvature of an outer diameter of the heating roller is set to 1.1 or more.
    Type: Application
    Filed: August 23, 2006
    Publication date: March 1, 2007
    Applicant: RICOH PRINTING SYSTEMS, LTD.
    Inventors: Masahiro Yagi, Toshio Ogiso, Shigeru Obata, Chikara Hiraoka, Toru Hanashima, Osamu Saito
  • Patent number: 7167670
    Abstract: An electro-photographic apparatus for conducting printing includes a fixing member fixing an unfixed toner image on a surface of a recording medium onto the recording medium. The fixing member includes a heating roller and a pressurizing member, and a mounting member on which the pressurizing member is mounted. The pressurizing member is supported by the mounting member in a substantially center part in a longitudinal direction of the pressurizing member.
    Type: Grant
    Filed: May 12, 2005
    Date of Patent: January 23, 2007
    Assignee: Ricoh Printing Systems, Ltd.
    Inventors: Shigeru Obata, Shunichi Oohara, Toshio Ogiso, Kenji Asuwa, Toru Hanashima, Chikara Hiraoka
  • Patent number: 7136615
    Abstract: A fixing unit that is provided in an image forming device and fixes a toner image transferred to paper is constructed of two belts, belt guides each of which guides the inner periphery of each of the belts, a heating member arranged in one of the belts or heating members arranged in both of the belts, a drive roller for driving the inner periphery of the belt, wherein the belts pinch paper on both surfaces thereof by the belt guides and carry the paper. This construction can realize a fixing unit reduced in size and capable of printing images at high speeds and shortening a rise time that elapses until the fixing unit reaches a fixable temperature.
    Type: Grant
    Filed: September 22, 2004
    Date of Patent: November 14, 2006
    Assignee: Ricoh Printing Systems, Ltd.
    Inventors: Shunjchi Oohara, Tetsuji Takegoshi, Toshio Ogiso, Shigeru Obata, Kenji Asuwa
  • Publication number: 20060008283
    Abstract: A fixing device comprising a first fixing means having a heating means disposed therein, a second fixing means, disposed to oppose to the first fixing means, for pinching a recording medium to form a first nip portion, a pair of transfer rollers, disposed at a downstream side of the recording medium, for forming a second nip portion, a guide for biasing the recording medium discharged from the transfer rollers towards the first fixing means side from one of the transfers, and means for biasing the guide towards the recording medium side.
    Type: Application
    Filed: July 7, 2005
    Publication date: January 12, 2006
    Inventors: Shunichi Oohara, Hiroyuki Seki, Toshio Ogiso, Shigeru Obata, Chikara Hiraoka, Toru Hanashima, Kazuhiro Wakamatsu