Patents by Inventor Yohichiroh Miyaguchi

Yohichiroh Miyaguchi 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: 7672604
    Abstract: An image forming apparatus having a developing apparatus using a development system in which toner is moved by means of a traveling wave electric field. The image forming apparatus comprises a plurality of developing apparatuses having toner conveyance members which convey toner by means of a phase-shift electric field created by voltages of n phases applied to a plurality of electrodes, to a region opposing an image carrier on which an electrostatic latent image is formed; and a voltage application device which applies a voltage having an average potential value between the potential of the image portions of the latent image on the image carrier and the non-image portions of same, to the electrodes of the toner conveyance members of the respective developing apparatuses.
    Type: Grant
    Filed: March 16, 2006
    Date of Patent: March 2, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Tomoko Takahashi, Masanori Horike, Katsuo Sakai, Yohichiroh Miyaguchi, Nobuaki Kondoh
  • Patent number: 7526238
    Abstract: Development device includes an electrostatic conveyance device, a supply device, and a collection device. The electrostatic conveyance device moves toner on a surface thereof in a toner conveyance direction by a phase-shifting electric field. The surface has upstream and downstream side ends where the phase-shifting electric field starts and ends, respectively. The supply device opposes the upstream side end to supply the toner onto the electrostatic conveyance surface. The toner supplied by the supply device onto the electrostatic conveyance surface is moved by the phase-shifting electric field to a development area of the electrostatic conveyance device opposing an image bearing. The collection device opposes the downstream side end and collects the toner moved on the electrostatic conveyance surface to a downstream side of the development area of the electrostatic conveyance device in the toner conveyance direction without contributing to the development.
    Type: Grant
    Filed: March 8, 2006
    Date of Patent: April 28, 2009
    Assignee: Ricoh Company, Ltd.
    Inventors: Masaaki Yamada, Masanori Horike, Yohichiroh Miyaguchi, Nobuaki Kondoh, Yoshinori Nakagawa
  • Patent number: 7308222
    Abstract: An image forming apparatus including an image carrier configured to have a latent image formed thereon, a developer carrier configured to supply toner, and a conveying member configured to receive toner from the developer carrier and to convey the toner to the image carrier. The conveying member includes first and second electrodes disposed a predetermined distance from one another. A first voltage application unit is configured to apply a first voltage to the developer carrier. A second voltage application unit is configured to apply a second voltage to the conveying member such that a ratio of a potential difference between the conveying member and the developer carrier to a distance between the conveying member and the developer carrier is less than a ratio of the second voltage to the predetermined distance.
    Type: Grant
    Filed: March 9, 2006
    Date of Patent: December 11, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Yoshinori Nakagawa, Masanori Horike, Yohichiroh Miyaguchi, Nobuaki Kondoh, Katsuo Sakai
  • Patent number: 7236720
    Abstract: An image forming apparatus is disclosed that is able to improve transfer efficiency and image quality. The image forming apparatus includes an organic photo-conductor with latent images formed thereon, and a developing unit for developing the latent images. The organic photo-conductor has surface friction coefficient less than or equal to 0.3. The developing unit develops the latent images while transporting a two-composition developing agent including a toner T and a carrier C by a traveling wave electric field.
    Type: Grant
    Filed: December 15, 2004
    Date of Patent: June 26, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Yasushi Nakazato, Masanori Horike, Yohichiroh Miyaguchi, Nobuaki Kondoh, Katsuo Sakai
  • Publication number: 20060251449
    Abstract: An image forming apparatus having a developing apparatus using a development system in which toner is moved by means of a traveling wave electric field. The image forming apparatus comprises a plurality of developing apparatuses having toner conveyance members which convey toner by means of a phase-shift electric field created by voltages of n phases applied to a plurality of electrodes, to a region opposing an image carrier on which an electrostatic latent image is formed; and a voltage application device which applies a voltage having an average potential value between the potential of the image portions of the latent image on the image carrier and the non-image portions of same, to the electrodes of the toner conveyance members of the respective developing apparatuses.
    Type: Application
    Filed: March 16, 2006
    Publication date: November 9, 2006
    Inventors: Tomoko Takahashi, Masanori Horike, Katsuo Sakai, Yohichiroh Miyaguchi, Nobuaki Kondoh
  • Publication number: 20060216071
    Abstract: Development device includes an electrostatic conveyance device, a supply device, and a collection device. The electrostatic conveyance device moves toner on a surface thereof in a toner conveyance direction by a phase-shifting electric field. The surface has upstream and downstream side ends where the phase-shifting electric field starts and ends, respectively. The supply device opposes the upstream side end to supply the toner onto the electrostatic conveyance surface. The toner supplied by the supply device onto the electrostatic conveyance surface is moved by the phase-shifting electric field to a development area of the electrostatic conveyance device opposing an image bearing. The collection device opposes the downstream side end and collects the toner moved on the electrostatic conveyance surface to a downstream side of the development area of the electrostatic conveyance device in the toner conveyance direction without contributing to the development.
    Type: Application
    Filed: March 8, 2006
    Publication date: September 28, 2006
    Inventors: Masaaki Yamada, Masanori Horike, Yohichiroh Miyaguchi, Nobuaki Kondoh, Yoshinori Nakagawa
  • Publication number: 20050158073
    Abstract: An image forming apparatus is disclosed that is able to improve transfer efficiency and image quality. The image forming apparatus includes an organic photo-conductor with latent images formed thereon, and a developing unit for developing the latent images. The organic photo-conductor has surface friction coefficient less than or equal to 0.3. The developing unit develops the latent images while transporting a two-composition developing agent including a toner T and a carrier C by a traveling wave electric field.
    Type: Application
    Filed: December 15, 2004
    Publication date: July 21, 2005
    Inventors: Yasushi Nakazato, Masanori Horike, Yohichiroh Miyaguchi, Nobuaki Kondoh, Katsuo Sakai
  • Patent number: 6597884
    Abstract: An electrophotographic image forming apparatus of the present invention deposits charged toner on a latent image formed on a photoconductive drum or similar image carrier to thereby produce a corresponding toner image. The apparatus includes a toner flying device for electrostatically conveying the toner along the conveying surface of a conveyance board to one end of the conveyance board. The toner is caused to fly toward the image carrier from the end of the conveyance board.
    Type: Grant
    Filed: September 10, 2001
    Date of Patent: July 22, 2003
    Assignee: Ricoh Company, Ltd.
    Inventors: Yohichiroh Miyaguchi, Takeshi Takemoto, Hiroyuki Okamoto, Chikara Imai, Katsuo Sakai, Nobuaki Kondou, Tsukuru Kai, Makoto Obu
  • Publication number: 20020037182
    Abstract: An electrophotographic image forming apparatus of the present invention deposits charged toner on a latent image formed on a photoconductive drum or similar image carrier to thereby produce a corresponding toner image. The apparatus includes a toner flying device for electrostatically conveying the toner along the conveying surface of a conveyance board to one end of the conveyance board. The toner is caused to fly toward the image carrier from the end of the conveyance board.
    Type: Application
    Filed: September 10, 2001
    Publication date: March 28, 2002
    Applicant: Ricoh Company, Ltd.
    Inventors: Yohichiroh Miyaguchi, Takeshi Takemoto, Hiroyuki Okamoto, Chikara Imai, Katsuo Sakai, Nobuaki Kondou, Tsukuru Kai, Makoto Obu