Patents by Inventor Atsushi Nakafuji

Atsushi Nakafuji 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: 20050117943
    Abstract: An image forming apparatus, includes an image forming mechanism configured to form an image, and a fixing unit configured to fix a toner image formed on a recording medium. The fixing unit includes a fixing device having a first endless moving member configured to rotate, and a second endless moving member configured to rotate to form a nip area together with the first endless moving member to fix, at the nip area, a toner image disposed on the recording medium onto the recording medium with heat and pressure, the second endless moving member including a surface layer having a universal hardness HU and a maximum nip surface pressure P each within a predetermined range.
    Type: Application
    Filed: November 29, 2004
    Publication date: June 2, 2005
    Inventors: Atsushi Nakafuji, Hiroyuki Kunii, Yukimichi Someya, Katsuhiro Echigo, Takashi Fujita, Hisashi Kikuchi, Toshihiko Baba, Shigeo Kurotaka
  • Publication number: 20050111871
    Abstract: An image forming apparatus of the present invention includes a fixing device for fixing a toner image formed on a recording medium. A heat source is applied with power for generating heat to thereby heating the heating device. A drive circuit includes a storage capable of being selectively charged or discharged and a charger for charging the storage by being supplied with power from a commercial power supply. A discharging device discharges the storage in a non-use mode in which the apparatus is not used.
    Type: Application
    Filed: January 3, 2005
    Publication date: May 26, 2005
    Inventors: Atsushi Nakafuji, Shigeo Kurotaka, Katsuhiro Echigo, Takashi Fujita, Hisashi Kikuchi, Jun Yura, Toshihiko Baba, Hirokazu Ikenoue
  • Patent number: 6897409
    Abstract: A fixing device for forming a toner image formed on a recording medium includes a heat roller accommodating a halogen heater. The halogen heater includes a glass tube formed of transparent quartz and provided with a wall thickness of 0.8 mm or below to increase transmission thereof. The increased transmission reduces a heat loss ascribable to the glass tube at the time of warm-up of the fixing device. The heat roller has such a thermal capacity that it can be warmed up in 10 seconds or less. The glass tube is filled with inactive gas whose major component is krypton or xenon. A tungsten filament accommodated in the glass tube has its diameter reduced in order to implement a color temperature of 2,500 K or above. An image forming apparatus using the fixing device is also disclosed.
    Type: Grant
    Filed: June 3, 2003
    Date of Patent: May 24, 2005
    Assignee: Ricoh Company, Ltd.
    Inventors: Jun Yura, Takashi Fujita, Hirokazu Ikenoue, Atsushi Nakafuji
  • Publication number: 20050025534
    Abstract: An intermediary transfer apparatus for transferring an unfixed image from an intermediary transfer member to a recording medium is disclosed. The intermediary transfer apparatus includes a heating unit for selectively heating a prescribed portion of the intermediary transfer member on which the unfixed image is situated, in a width direction of the intermediary transfer member, the width direction of the intermediary transfer member perpendicularly intersecting the direction in which the unfixed image is conveyed.
    Type: Application
    Filed: June 23, 2004
    Publication date: February 3, 2005
    Inventors: Takashi Fujita, Shigeo Kurotaka, Yukimichi Someya, Hiroyuki Kunii, Atsushi Nakafuji, Hisashi Kikuchi, Katsuhiro Echigo, Toshihiko Baba, Kohji Ue
  • Publication number: 20050025537
    Abstract: A fixing device including a fixing belt, a drive roller and a press roller. The drive roller is configured to drive the fixing belt, and press roller is arranged so as to face the drive roller across the fixing belt, and exert pressure toward the fixing belt. The drive roller and the press roller are able to rotate so that the peripheral velocity of the drive roller is greater than the peripheral velocity of the press roller. According to the fixing device image defects, including image difference, are less likely to occur when fixing an image on a recording sheet.
    Type: Application
    Filed: June 21, 2004
    Publication date: February 3, 2005
    Inventors: Katsuhiro Echigo, Shigeo Kurotaka, Takashi Fujita, Toshihiko Baba, Hisashi Kikuchi, Yukimichi Someya, Hiroyuki Kunii, Atsushi Nakafuji
  • Patent number: 6847792
    Abstract: An image forming apparatus of the present invention includes a fixing device for fixing a toner image formed on a recording medium. A heat source is applied with power for generating heat to thereby heating the heating device. A drive circuit includes a storage capable of being selectively charged or discharged and a charger for charging the storage by being supplied with power from a commercial power supply. A discharging device discharges the storage in a non-use mode in which the apparatus is not used.
    Type: Grant
    Filed: November 25, 2002
    Date of Patent: January 25, 2005
    Assignee: Ricoh Company, Ltd.
    Inventors: Atsushi Nakafuji, Shigeo Kurotaka, Katsuhiro Echigo, Takashi Fujita, Hisashi Kikuchi, Jun Yura, Toshihiko Baba, Hirokazu Ikenoue
  • Publication number: 20040265017
    Abstract: A fixing apparatus includes a fixing member to be heated and a pressure-contacting member for pressure contacting the fixing member. The fixing apparatus directs and conveys a recording member through a nip formed between the fixing member and pressure applying member in such a manner that a toner image carried on a recording member contacts the fixing member in order to be fixed thereto with heat and pressure. The fixing apparatus is configured to direct a tip margin of the recording member toward the pressure applying member across a virtual linear extension line drawn from a downstream end to upstream end of the nip when only the tip margin exits from the nip. A fixing member side separation device may be separately provided from the surface of the fixing apparatus so as to separate the recording member exiting from the nip. A gap formed between the downstream end of the nip and the tip of the fixing member side separation device is set smaller than the width of the tip margin.
    Type: Application
    Filed: July 29, 2004
    Publication date: December 30, 2004
    Inventors: Hisashi Kikuchi, Shigeo Kurotaka, Kiyoshi Ohshima, Takashi Fujita, Toshihiko Baba, Atsushi Nakafuji, Hirokazu Ikenoue, Jun Yura, Katsuhiro Echigo, Hideki Kosugi
  • Publication number: 20040190959
    Abstract: A fixing member heat bonds a toner on a recording material. The fixing member includes a releasing layer, a layer of elastic material, below the releasing layer, and a layer of adiabatic and hygroscopic material, below the layer of elastic material. The layer of elastic material includes a layer of electrically conducting material to pass electric currents, an adiabatic, elastic, and hydrophobic material, and a porous material to the release of the moisture absorbed by the layer of adiabatic and hygroscopic material.
    Type: Application
    Filed: January 9, 2004
    Publication date: September 30, 2004
    Inventors: Hisashi Kikuchi, Toshihiko Baba, Shigeo Kurotaka, Atsushi Nakafuji, Hiroyuki Kunii, Yukimichi Someya, Katsuhiro Echigo, Takashi Fujita
  • Patent number: 6795676
    Abstract: A fixing apparatus includes a fixing member to be heated and a pressure-contacting member for pressure contacting the fixing member. The fixing apparatus directs and conveys a recording member through a nip formed between the fixing member and pressure applying member in such a manner that a toner image carried on a recording member contacts the fixing member in order to be fixed thereto with heat and pressure. The fixing apparatus is configured to direct a tip margin of the recording member toward the pressure applying member across a virtual linear extension line drawn from a downstream end to upstream end of the nip when only the tip margin exits from the nip. A fixing member side separation device may be separately provided from the surface of the fixing apparatus so as to separate the recording member exiting from the nip. A gap formed between the downstream end of the nip and the tip of the fixing member side separation device is set smaller than the width of the tip margin.
    Type: Grant
    Filed: June 3, 2002
    Date of Patent: September 21, 2004
    Assignee: Ricoh Company, LTD
    Inventors: Hisashi Kikuchi, Shigeo Kurotaka, Kiyoshi Ohshima, Takashi Fujita, Toshihiko Baba, Atsushi Nakafuji, Hirokazu Ikenoue, Jun Yura, Echigo Katsuhiro, Hideki Kosugi
  • Patent number: 6795678
    Abstract: A fixing device for an image forming apparatus of the present invention includes an endless belt passed over a plurality of members for conveying a sheet in contact with a toner image carried thereon. A pressing member faces the above members with the intermediary of the belt. A first member, which is one of the plurality of members, constitutes a heating member for heating the belt. A second member, which is another one of the members, faces the pressing member with the intermediary of the belt. A third member, which is another one of the members, constitutes a stationary member facing the pressing member with the intermediary of the belt. The pressing member and first member and the pressing member and second member respectively form a first and a second nip therebetween. The toner image on the sheet is fixed by being sequentially conveyed via the first and second nips.
    Type: Grant
    Filed: November 29, 2002
    Date of Patent: September 21, 2004
    Assignee: Ricoh Company, Ltd.
    Inventors: Jun Yura, Takashi Fujita, Katsuhiro Echigo, Shigeo Kurotaka, Toshihiko Baba, Hisashi Kikuchi, Atsushi Nakafuji, Hirokazu Ikenoue
  • Publication number: 20040111888
    Abstract: A heating roller including a core of hollow cylinder form and wherein a thickness of the core is thicker in a center portion thereof than in both end portions thereof. Further, a heating device may have the heating roller, a fixing device may have the heating roller and the heating device, and an image forming apparatus may have the heating roller, the heating device and the fixing device.
    Type: Application
    Filed: July 23, 2003
    Publication date: June 17, 2004
    Inventors: Jun Yura, Takashi Fujita, Hirokazu Ikenoue, Atsushi Nakafuji
  • Publication number: 20040022552
    Abstract: A fixing device included in an image forming apparatus for fixing a toner image formed on a sheet of the present invention includes a rotatable member and a pressing member forming a nip, which corresponds to a conveying zone, therebetween. The rotatable member and pressing member convey the sheet via the nip for thereby fixing the toner image on the sheet. A heating member heats the surface of the rotatable member in contact with therewith. Part of the rotatable member and part of the heating member contacting each other respectively have a convex shape and a concave shape complementary to the convex shape.
    Type: Application
    Filed: May 30, 2003
    Publication date: February 5, 2004
    Inventors: Jun Yura, Hirokazu Ikenoue, Katsuhiro Echigo, Takashi Fujita, Hisashi Kikuchi, Atsushi Nakafuji, Shigeo Kurotaka, Toshihiko Baba, Kazuhito Kishi, Eriko Konno
  • Patent number: 6646227
    Abstract: A fixing device for forming a toner image formed on a recording medium includes a heat roller accommodating a radiation heater. The radiation heater includes a glass tube formed of transparent quartz and provided with a wall thickness of 0.8 mm or below to increase transmission thereof. The increased transmission reduces a heat loss ascribable to the glass tube at the time of warm-up of the fixing device. The heat roller has such a thermal capacity that it can be warmed up in 10 seconds or less. The glass tube is filled with inactive gas whose major component is krypton or xenon. A tungsten filament accommodated in the glass tube has its diameter reduced in order to implement a color temperature of 2,500 K or above. An image forming apparatus uses the fixing device.
    Type: Grant
    Filed: April 26, 2002
    Date of Patent: November 11, 2003
    Assignee: Ricoh Company, Ltd.
    Inventors: Jun Yura, Takashi Fujita, Hirokazu Ikenoue, Atsushi Nakafuji
  • Patent number: 6636718
    Abstract: A heating roller including a core of hollow cylinder form and wherein a thickness of the core is thicker in a center portion thereof than in both end portions thereof. Further, a heating device may have the heating roller, a fixing device may have the heating roller and the heating device, and an image forming apparatus may have the heating roller, the heating device and the fixing device.
    Type: Grant
    Filed: June 7, 2001
    Date of Patent: October 21, 2003
    Assignee: Ricoh Company, Ltd.
    Inventors: Jun Yura, Takashi Fujita, Hirokazu Ikenoue, Atsushi Nakafuji
  • Publication number: 20030192869
    Abstract: A fixing device for forming a toner image formed on a recording medium includes a heat roller accommodating a halogen heater. The halogen heater includes a glass tube formed of transparent quartz and provided with a wall thickness of 0.8 mm or below to increase transmission thereof. The increased transmission reduces a heat loss ascribable to the glass tube at the time of warm-up of the fixing device. The heat roller has such a thermal capacity that it can be warmed up in 10 seconds or less. The glass tube is filled with inactive gas whose major component is krypton or xenon. A tungsten filament accommodated in the glass tube has its diameter reduced in order to implement a color temperature of 2,500 K or above. An image forming apparatus using the fixing device is also disclosed.
    Type: Application
    Filed: June 3, 2003
    Publication date: October 16, 2003
    Inventors: Jun Yura, Takashi Fujita, Hirokazu Ikenoue, Atsushi Nakafuji
  • Patent number: 6631253
    Abstract: A fixing device for fixing a toner image formed on a recording medium conveyed to a nip for fixation of the present invention includes a rotary body, a stationary heating member not forming the nip, a fixing belt passed over the rotary body and heating member, and a pressing member held in contact with the fixing belt. A resistance heating body is formed on the heating member with the intermediary of an electric insulation layer.
    Type: Grant
    Filed: December 19, 2001
    Date of Patent: October 7, 2003
    Assignee: Ricoh Company, Ltd.
    Inventors: Atsushi Nakafuji, Takashi Fujita, Hirokazu Ikenoue, Jun Yura
  • Publication number: 20030103788
    Abstract: A fixing device for an image forming apparatus of the present invention includes an endless belt passed over a plurality of members for conveying a sheet in contact with a toner image carried thereon. A pressing member faces the above members with the intermediary of the belt. A first member, which is one of the plurality of members, constitutes a heating member for heating the belt. A second member, which is another one of the members, faces the pressing member with the intermediary of the belt. A third member, which is another one of the members, constitutes a stationary member facing the pressing member with the intermediary of the belt. The pressing member and first member and the pressing member and second member respectively form a first and a second nip therebetween. The toner image on the sheet is fixed by being sequentially conveyed via the first and second nips.
    Type: Application
    Filed: November 29, 2002
    Publication date: June 5, 2003
    Inventors: Jun Yura, Takashi Fujita, Katsuhiro Echigo, Shigeo Kurotaka, Toshihiko Baba, Hisashi Kikuchi, Atsushi Nakafuji, Hirokazu Ikenoue
  • Publication number: 20030099479
    Abstract: An image forming apparatus of the present invention includes a fixing device for fixing a toner image formed on a recording medium. A heat source is applied with power for generating heat to thereby heating the heating device. A drive circuit includes a storage capable of being selectively charged or discharged and a charger for charging the storage by being supplied with power from a commercial power supply. A discharging device discharges the storage in a non-use mode in which the apparatus is not used.
    Type: Application
    Filed: November 25, 2002
    Publication date: May 29, 2003
    Inventors: Atsushi Nakafuji, Shigeo Kurotaka, Katsuhiro Echigo, Takashi Fujita, Hisashi Kikuchi, Jun Yura, Toshihiko Baba, Hirokazu Ikenoue
  • Patent number: 6559421
    Abstract: A fixing device for forming a toner image formed on a recording medium includes a heat roller accommodating a halogen heater. The halogen heater includes a glass tube formed of transparent quartz and provided with a wall thickness of 0.8 mm or below to increase transmission thereof. The increased transmission reduces a heat loss ascribable to the glass tube at the time of warm-up of the fixing device. The heat roller has such a thermal capacity that it can be warmed up in 10 seconds or loss. The glass tube is filled with inactive gas whose major component is krypton or xenon. A tungsten filament accommodated in the glass tube has its diameter reduced in order to implement a color temperature of 2,500 K or above. An image forming apparatus using the fixing device is also disclosed.
    Type: Grant
    Filed: October 30, 2000
    Date of Patent: May 6, 2003
    Assignee: Ricoh Company, Ltd.
    Inventors: Jun Yura, Takashi Fujita, Hirokazu Ikenoue, Atsushi Nakafuji
  • Patent number: 6542705
    Abstract: A heating device of the present invention includes a main power source and an auxiliary power source implemented by a chargeable capacitor. A heater is made up of a main heating element that heats when supplied with power from the main power source and an auxiliary heating element that heat when supplied with power from the auxiliary power source. A charger charges the capacitor of the auxiliary power source when supplied with power from the main power source. A switch selectively causes the auxiliary power source to be charged or to feed power to the auxiliary heating element. A controller adjusts the power to be fed from the auxiliary power source to the auxiliary heating element.
    Type: Grant
    Filed: October 1, 2001
    Date of Patent: April 1, 2003
    Assignee: Ricoh Company, Ltd.
    Inventors: Takashi Fujita, Hirokazu Ikenoue, Atsushi Nakafuji, Kazuhito Kishi, Eriko Chiba