Patents by Inventor Shigeo Kurotaka

Shigeo Kurotaka 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: 8515323
    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: November 6, 2009
    Date of Patent: August 20, 2013
    Assignee: Ricoh Company, Ltd.
    Inventors: Hisashi Kikuchi, Shigeo Kurotaka, Kiyoshi Ohshima, Takashi Fujita, Toshihiko Baba, Atsushi Nakafuji, Hirokazu Ikenoue, Jun Yura, Katsuhiro Echigo, Hideki Kosugi
  • Patent number: 7738827
    Abstract: The fixing unit satisfies following three conditions. That is, (1) 2.4×103×d/(TC×t)<T0, where d is a thickness of the unfixed toner layer in meters, TC is a thermal conductivity of toner in W/mK, and t is the fixing time in seconds; (2) a temperature Ttop of a topmost layer of the toner layer is not greater than the minimum temperature TOFF at which the hot offset of the surface of the first fixing member occurs when the fixing time is set to 1 seconds; and (3) a temperature Tbot of a bottommost layer of the toner layer that is in contact with the recording medium is not less than the lower limit temperature TMIN for fixing of the surface of the first fixing member when the fixing time is set to 1 second.
    Type: Grant
    Filed: December 12, 2005
    Date of Patent: June 15, 2010
    Assignee: Ricoh Company, Limited
    Inventors: Yukimichi Someya, Takashi Fujita, Hisashi Kikuchi, Katsuhiro Echigo, Shigeo Kurotaka, Toshihiko Baba, Hiroyuki Kunii, Atsushi Nakafuji
  • Patent number: 7693471
    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: February 5, 2008
    Date of Patent: April 6, 2010
    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
  • Publication number: 20100046994
    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: November 6, 2009
    Publication date: February 25, 2010
    Inventors: Hisashi KIKUCHI, Shigeo Kurotaka, Kiyoshi Ohshima, Takashi Fujita, Toshihiko Baba, Atsushi Nakafuji, Hirokazu Ikenoue, Jun Yura, Katsuhiro Echigo, Hideki Kosugi
  • Patent number: 7570911
    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: Grant
    Filed: December 28, 2006
    Date of Patent: August 4, 2009
    Assignee: Ricoh Co., Ltd.
    Inventors: Atsushi Nakafuji, Hiroyuki Kunii, Yukimichi Someya, Katsuhiro Echigo, Takashi Fujita, Hisashi Kikuchi, Toshihiko Baba, Shigeo Kurotaka
  • Patent number: 7433641
    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: Grant
    Filed: August 9, 2005
    Date of Patent: October 7, 2008
    Assignee: Ricoh Company, Limited
    Inventors: Hisashi Kikuchi, Toshihiko Baba, Shigeo Kurotaka, Atsushi Nakafuji, Hiroyuki Kunii, Yukimichi Someya, Katsuhiro Echigo, Takashi Fujita
  • Publication number: 20080138124
    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: February 5, 2008
    Publication date: June 12, 2008
    Inventors: Hisashi Kikuchi, Shigeo Kurotaka, Kiyoshi Ohshima, Takashi Fujita, Toshihiko Baba, Atsushi Nakafuji, Hirokazu Ikenoue, Jun Yura, Echigo Katsuhiro, Hideki Kosugi
  • Patent number: 7369803
    Abstract: A fixing device for fixing image information on a recording medium passing a nip of the present invention includes a rotatable member for transferring and conveying a non-fixed image, a first heating means for heating an image present on the rotatable member and a rotatable pressing member forming a nip in combination with the rotatable member. A heat pipe extends in parallel to the axis of the rotatable member. A radiating member is positioned at one end of the heat pipe while a heating member is positioned at the other end of the heat pipe.
    Type: Grant
    Filed: December 1, 2005
    Date of Patent: May 6, 2008
    Assignee: Ricoh Company, Ltd.
    Inventors: Katsuhiro Echigo, Takashi Fujita, Shigeo Kurotaka, Hisashi Kikuchi, Yukimichi Someya, Toshihiko Baba, Hiroyuki Kunii, Atsushi Nakafuji, Kohji Ue
  • Patent number: 7346305
    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: November 7, 2006
    Date of Patent: March 18, 2008
    Assignee: Ricoh Company, Ltd
    Inventors: Hisashi Kikuchi, Shigeo Kurotaka, Kiyoshi Ohshima, Takashi Fujita, Toshihiko Baba, Atsushi Nakafuji, Hirokazu Ikenoue, Jun Yura, Katsuhiro Echigo, Hideki Kosugi
  • Patent number: 7333760
    Abstract: A fixing device including a magnetic field generating device to generate a magnetic field, a fixing member to heat a recording material by heat generated in a first recording material passing area having a first width on the fixing member by electromagnetic induction heat generation by the magnetic field formed by the magnetic field generating device, a pressing member to form a nip portion where the pressing member and the fixing member press against each other to fix an unfixed image on the recording material, and at least one radiation heating device configured to heat a second recording material passing area having a second width.
    Type: Grant
    Filed: June 24, 2005
    Date of Patent: February 19, 2008
    Assignee: Ricoh Company, Ltd.
    Inventors: Toshihiko Baba, Shigeo Kurotaka, Katsuhiro Echigo, Takashi Fujita, Hisashi Kikuchi, Yukimichi Someya, Hiroyuki Kunii, Atsushi Nakafuji, Kohji Ue
  • Patent number: 7299003
    Abstract: A fixing belt is heated by electromagnetic induction. The fixing belt has a heat generating layer that has a thickness not greater than 40 ?m and a releasing layer that has a thickness not less than 10 ?m. A toner that includes at least a binder resin, a colorant, and a mold releasing agent, and has a glass transition temperature in a range of 35° C. to 50° C. and an outflow-start temperature in a range of 80° C. to 110° C., is used.
    Type: Grant
    Filed: January 28, 2005
    Date of Patent: November 20, 2007
    Assignee: Ricoh Company, Limited
    Inventors: Shigeo Kurotaka, Masami Tomita, Katsuhiro Echigo, Takashi Fujita, Toshihiko Baba, Hisashi Kikuchi, Hiroyuki Kunii, Atsushi Nakafuji, Yukimichi Someya, Kohji Ue
  • Patent number: 7269384
    Abstract: A transfer-fixing unit for use in an image forming apparatus having an intermediate transfer member and a transfer-fixing unit, which includes a pressure member and a transfer-fixing member. The intermediate transfer member receives a toner image thereon. The transfer-fixing member has a deformable surface layer thereon, and directly receives the toner image from the intermediate transfer member, and transfers and fixes the toner image to a recording medium while deforming the surface layer in response to surface irregularities of the recording medium. The transfer-fixing member forms a nip portion with the pressure member and presses the recording medium at the nip portion when the recording medium passes through the nip portion with a nip time.
    Type: Grant
    Filed: July 11, 2005
    Date of Patent: September 11, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Yukimichi Someya, Takashi Fujita, Atsushi Nakafuji, Katsuhiro Echigo, Hiroyuki Kunii, Shigeo Kurotaka, Hisashi Kikuchi, Toshihiko Baba, Kohji Ue, Hiromitsu Takagaki, Hirohmi Tamura
  • Patent number: 7254362
    Abstract: A fixing device containing at least one fixing member configured to fix a toner image on a transfer material, which includes a first substrate and a pressing member configured to form a nip with the at least one fixing member, which includes a second substrate, and a heater. At least one of the at least one fixing member and the pressing member further contains a heat insulating layer overlying the first or second substrate.
    Type: Grant
    Filed: November 8, 2004
    Date of Patent: August 7, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Hisashi Kikuchi, Takashi Fujita, Yukimichi Someya, Katsuhiro Echigo, Hiroyuki Kunii, Shigeo Kurotaka, Atsushi Nakafuji
  • Patent number: 7251429
    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: May 22, 2006
    Date of Patent: July 31, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Atsushi Nakafuji, Shigeo Kurotaka, Katsuhiro Echigo, Takashi Fujita, Hisashi Kikuchi, Jun Yura, Toshihiko Baba, Hirokazu Ikenoue
  • Patent number: 7233762
    Abstract: An unfixed toner image on a transferring and fixing belt is passed through a pair of toner integrating rollers. A surface side of the toner integrated that is in contact with a paper, is heated by a halogen heater to impart a tackiness required for fixing. As a result of this, a temperature of a surface side of the toner that is in contact with the transferring and fixing belt is not as high as a temperature of the surface side of the toner that is in contact with the paper. Therefore, even if the toner is pressurized, and transferred and fixed at a fixing nip, a difference in an area of the toner is small. This enables to achieve a good image quality.
    Type: Grant
    Filed: March 18, 2005
    Date of Patent: June 19, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroyuki Kunii, Katsuhiro Echigo, Hisashi Kikuchi, Atsushi Nakafuji, Yukimichi Someya, Shigeo Kurotaka, Toshihiko Baba, Kohji Ue, Takashi Fujita
  • Patent number: 7224928
    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: July 29, 2004
    Date of Patent: May 29, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Hisashi Kikuchi, Shigeo Kurotaka, Kiyoshi Ohshima, Takashi Fujita, Toshihiko Baba, Atsushi Nakafuji, Hirokazu Ikenoue, Jun Yura, Katsuhiro Echigo, Hideki Kosugi
  • Publication number: 20070104520
    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: December 28, 2006
    Publication date: May 10, 2007
    Inventors: Atsushi Nakafuji, Hiroyuki Kunii, Yukimichi Someya, Katsuhiro Echigo, Takashi Fujita, Hisashi Kikuchi, Toshihiko Baba, Shigeo Kurotaka
  • Publication number: 20070071513
    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: November 7, 2006
    Publication date: March 29, 2007
    Inventors: Hisashi KIKUCHI, Shigeo Kurotaka, Kiyoshi Oshima, Takashi Fujita, Toshihiko Baba, Atsushi Nakafuji, Hirokazu Ikenoue, Jun Yura, Katsuhiro Echigo, Hideki Kosugi
  • Patent number: 7177580
    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: Grant
    Filed: November 29, 2004
    Date of Patent: February 13, 2007
    Assignee: Ricoh Co., Ltd.
    Inventors: Atsushi Nakafuji, Hiroyuki Kunii, Yukimichi Someya, Katsuhiro Echigo, Takashi Fujita, Hisashi Kikuchi, Toshihiko Baba, Shigeo Kurotaka
  • Patent number: 7139520
    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: Grant
    Filed: June 21, 2004
    Date of Patent: November 21, 2006
    Assignee: Ricoh Company, Ltd.
    Inventors: Katsuhiro Echigo, Shigeo Kurotaka, Takashi Fujita, Toshihiko Baba, Hisashi Kikuchi, Yukimichi Someya, Hiroyuki Kunii, Atsushi Nakafuji