Patents by Inventor Masahiko Kamijoh

Masahiko Kamijoh 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: 7469889
    Abstract: An image forming apparatus including a sheet feed apparatus configured to sequentially separate sheets stacked on a sheet stacking member. The sheet feed apparatus includes a sheet feed roller configured to come in pressing contact with the uppermost sheet in order to feed the sheet. The sheet feed apparatus also includes a tilt member arranged to oppose the sheet feed roller. The sheet feed apparatus includes a contact face arranged to press against the sheet feed roller. The sheet feed apparatus also includes a tilt face arranged to contact an edge of the uppermost sheet. The tilt face and the contact face are formed from one of polybutylene terephthalate (PBT), polyethylene (PE), metal, poly-ether-ether-ketone (PEEK), and polyimide (PI) to provide superior wear resistance.
    Type: Grant
    Filed: July 3, 2003
    Date of Patent: December 30, 2008
    Assignee: Ricoh Company, Ltd.
    Inventor: Masahiko Kamijoh
  • Patent number: 7013108
    Abstract: A fixing device including a heat transmitting unit and a sheet unit. The heat transmitting unit has a heating source, which can be for example disposed inside the heat transmitting unit. The sheet unit is in contact with the heat transmitting unit for applying a pressure against the heat transmitting unit. One end of the sheet unit is fixed on an installation fitment that is arrange at an upstream side of a transporting direction of a recording paper with respect to the heat transmitting unit, and the other end of the sheet unit is pressed to be in contact with the heat transmitting unit. Furthermore, when the recording paper, where a toner image has been transferred thereon, passes through a nip portion between the heat transmitting unit and the sheet unit, the toner image is fixed by pressing and heating onto the recording paper.
    Type: Grant
    Filed: July 2, 2004
    Date of Patent: March 14, 2006
    Assignee: Ricoh Company, Ltd.
    Inventors: Kohta Takenaka, Hidehiko Fujiwara, Masahiko Kamijoh
  • Patent number: 6907218
    Abstract: An image forming device comprises a fixing device that is composed of a fixing roller and a sheet-shaped pressure unit. The position of the fixing nip portion is set above a plane containing a transporting direction of the recording paper at the transferring nip portion. A recording paper guider is further disposed for guiding the recording paper transported by the transferring roller to the fixing roller. The guiding surface of the recording paper guider is inclined and gradually raised beginning at the transferring roller side (as the lowest position).
    Type: Grant
    Filed: September 27, 2002
    Date of Patent: June 14, 2005
    Assignee: Ricoh Company, Ltd.
    Inventors: Hidehiko Fujiwara, Masahiko Kamijoh, Kohta Takenaka
  • Publication number: 20040240914
    Abstract: A fixing device including a heat transmitting unit and a sheet unit. The heat transmitting unit has a heating source, which can be for example disposed inside the heat transmitting unit. The sheet unit is in contact with the heat transmitting unit for applying a pressure against the heat transmitting unit. One end of the sheet unit is fixed on an installation fitment that is arrange at an upstream side of a transporting direction of a recording paper with respect to the heat transmitting unit, and the other end of the sheet unit is pressed to be in contact with the heat transmitting unit. Furthermore, when the recording paper, where a toner image has been transferred thereon, passes through a nip portion between the heat transmitting unit and the sheet unit, the toner image is fixed by pressing and heating onto the recording paper.
    Type: Application
    Filed: July 2, 2004
    Publication date: December 2, 2004
    Inventors: Kohta Takenaka, Hidehiko Fujiwara, Masahiko Kamijoh
  • Patent number: 6801744
    Abstract: An image fixing device a pressure plate that presses against a fixing roller. The pressure plate is made of bridged PTFE or at least coated with bridged PTFE. A heater is provided inside the fixing roller for heating the fixing roller. A paper with a toner image thereon is made to pass through a nipping part formed by the pressure plate and the fixing roller. The image is fixed to the paper by the application of the pressure and the heat.
    Type: Grant
    Filed: December 4, 2002
    Date of Patent: October 5, 2004
    Assignee: Ricoh Company, Limited
    Inventors: Hidehiko Fujiwara, Masahiko Kamijoh, Kohta Takenaka
  • Patent number: 6788916
    Abstract: A fixing device, including: a heat transmitting unit and a sheet unit. The heat transmitting unit has a heating source, which can be for example disposed inside the heat transmitting unit. The sheet unit is in contact with the heat transmitting unit for applying a pressure against the heat transmitting unit. One end of the sheet unit is fixed on an installation fitment that is arranged at an upstream side of a transporting direction of a recording paper with respect to the heat transmitting unit, and the other end of the sheet unit is pressed to be in contact with the heat transmitting unit. Furthermore, when the recording paper, where a toner image has been transferred thereon, passes through a nip portion between the heat transmitting unit and the sheet unit, the toner image is fixed by pressing and heating onto the recording paper.
    Type: Grant
    Filed: November 1, 2002
    Date of Patent: September 7, 2004
    Assignee: Ricoh Company, Ltd.
    Inventors: Kohta Takenaka, Hidehiko Fujiwara, Masahiko Kamijoh
  • Patent number: 6731902
    Abstract: A fixing device for a printing device is provided. The fixing device comprises a fixing unit, heated by a heating source; and a sheet-shaped pressure unit, having an elasticity and in contact with the fixing unit by pressing against the fixing unit. When a recording paper that a toner image has been transcribed thereon passes through a nip portion between the sheet pressing unit and the fixing unit, by pressing and heating, the toner image is fixed on the recording paper. In addition, a surface layer is formed on a surface of the fixing unit, wherein the surface layer comprises a material such as a glass fiber, a graphite, a bronze etc, for increasing a friction coefficient. Further, the surface has a water contact angle greater than or equal to 90°. By setting the friction coefficient of the surface of the fixing roller to a range that the toner does not adhere thereon, the transporting property of the recording paper can be improved.
    Type: Grant
    Filed: September 18, 2002
    Date of Patent: May 4, 2004
    Assignee: Ricoh Company, Ltd.
    Inventors: Kohta Takenaka, Masahiko Kamijoh, Hidehiko Fujiwara
  • Patent number: 6731900
    Abstract: A fixing device is provided, which has a fixing roller and a sheet. A recording paper where a toner image has been transcribed thereon is passed through a nip portion between the fixing roller and the sheet. By pressing and heating, the toner image is fixed on the recording paper. A heating line is wound on a surface opposite to a sheet's surface that is in contact with the fixing roller. By applying a power source to the heating line, the sheet is heated. When the recording paper enters the nip, the cause of the temperature suddenly lowering can be prevented.
    Type: Grant
    Filed: August 2, 2002
    Date of Patent: May 4, 2004
    Assignee: Ricoh Company, Ltd.
    Inventors: Kohta Takenaka, Masahiko Kamijoh, Hidehiko Fujiwara
  • Publication number: 20040065993
    Abstract: An image forming apparatus including a sheet feed apparatus configured to sequentially separate sheets stacked on a sheet stacking member. The sheet feed apparatus includes a sheet feed roller configured to come in pressing contact with the uppermost sheet in order to feed the sheet. The sheet feed apparatus also includes a tilt member arranged to oppose the sheet feed roller. The sheet feed apparatus includes a contact face arranged to press against the sheet feed roller. The sheet feed apparatus also includes a tilt face arranged to contact an edge of the uppermost sheet. The tilt face and the contact face are formed from one of polybutylene terephthalate (PBT), polyethylene (PE), metal, poly-ether-ether-ketone (PEEK), and polyimide (PI) to provide superior wear resistance.
    Type: Application
    Filed: July 3, 2003
    Publication date: April 8, 2004
    Inventor: Masahiko Kamijoh
  • Publication number: 20030103786
    Abstract: An image fixing device a pressure plate that presses against a fixing roller. The pressure plate is made of bridged PTFE or at least coated with bridged PTFE. A heater is provided inside the fixing roller for heating the fixing roller. A paper with a toner image thereon is made to pass through a nipping part formed by the pressure plate and the fixing roller. The image is fixed to the paper by the application of the pressure and the heat.
    Type: Application
    Filed: December 4, 2002
    Publication date: June 5, 2003
    Inventors: Hidehiko Fujiwara, Masahiko Kamijoh, Kohta Takenaka
  • Publication number: 20030099493
    Abstract: A fixing device, comprising: a heat transmitting unit and a sheet unit. The heat transmitting unit has a heating source, which can be for example, disposed inside the heat transmitting unit. The sheet unit is in contact with the heat transmitting unit for applying a pressure against the heat transmitting unit. One end of the sheet unit is fixed on an installation fitment that is arranged at an upstream side of a transporting direction of a recording paper with respect to the heat transmitting unit, and the other end of the sheet unit is pressed to be in contact with the heat transmitting unit. Furthermore, when the recording paper, where a toner image has been transferred thereon, passes through a nip portion between the heat transmitting unit and the sheet unit, the toner image is fixed by pressing and heating onto the recording paper.
    Type: Application
    Filed: November 1, 2002
    Publication date: May 29, 2003
    Inventors: Kohta Takenaka, Hidehiko Fujiwara, Masahiko Kamijoh
  • Publication number: 20030063934
    Abstract: A fixing device for a printing device is provided. The fixing device comprises a fixing unit, heated by a heating source; and a sheet-shaped pressure unit, having an elasticity and in contact with the fixing unit by pressing against the fixing unit When a recording paper that a toner image has been transcribed thereon passes through a nip portion between the sheet pressing unit and the fixing unit, by pressing and heating, the toner image is fixed on the recording paper. In addition, a surface layer is formed on a surface of the fixing unit, wherein the surface layer comprises a material such as a glass fiber, a graphite, a bronze etc, for increasing a friction coefficient. Further, the surface has a water contact angle greater than or equal to 90°. By setting the friction coefficient of the surface of the fixing roller to a range that the toner does not adhere thereon, the transporting property of the recording paper can be improved.
    Type: Application
    Filed: September 18, 2002
    Publication date: April 3, 2003
    Inventors: Kohta Takenaka, Masahiko Kamijoh, Hidehiko Fujiwara
  • Publication number: 20030063933
    Abstract: An image forming device comprises a fixing device that is composed of a fixing roller and a sheet-shaped pressure unit. The position of the fixing nip portion is set above a plane containing a transporting direction of the recording paper at the transferring nip portion. A recording paper guider is further disposed for guiding the recording paper transported by the transferring roller to the fixing roller. The guiding surface of the recording paper guider is inclined and gradually raised beginning at the transferring roller side (as the lowest position).
    Type: Application
    Filed: September 27, 2002
    Publication date: April 3, 2003
    Inventors: Hidehiko Fujiwara, Masahiko Kamijoh, Kohta Takenaka
  • Publication number: 20030026632
    Abstract: A fixing device is provided, which has a fixing roller and a sheet. The recording paper where the toner image has been transcribed thereon is passed through a nip portion between the fixing roller and the sheet. By pressing and heating, the toner image is fixed on the recording paper. A heating line is wound on a surface opposite to a sheet's surface that is in contact with the fixing roller. By applying a power source to the heating line, the sheet is heated. When the recording paper enters the nip, the cause of the temperature suddenly lowering can be prevented.
    Type: Application
    Filed: August 2, 2002
    Publication date: February 6, 2003
    Inventors: Kohta Takenaka, Masahiko Kamijoh, Hidehiko Fujiwara