Patents by Inventor Hirokatsu Suzuki

Hirokatsu Suzuki 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: 7941075
    Abstract: An image forming apparatus includes an image carrier, a charging unit including a charge member that is disposed facing the image carrier across a gap therebetween and charges the image carrier by using electrical discharge caused by applying thereto a voltage including an alternating current component superimposed on a direct current component, a latent image forming unit, a developing unit to supply toner for developing the latent image formed on the image carrier into a toner image and to collect residual toner remaining on the image carrier, a transfer unit, and a toner spreading member to spread toner on the image carrier and disposed upstream from the charging unit in a direction of movement of the image carrier and downstream from the transfer unit in the direction of movement of the image carrier.
    Type: Grant
    Filed: June 10, 2009
    Date of Patent: May 10, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Emiko Shiraishi, Shigekazu Enoki, Jun Yura, Hirokatsu Suzuki
  • Publication number: 20110058832
    Abstract: By using a black-image forming device, an abrasive pattern is formed on a sheet conveying belt so that toner is input to a contact section where a cleaning blade is in contact with the sheet conveying belt. After the toner is input to the contact section where the cleaning blade is in contact with the sheet conveying belt and then the sheet conveying belt makes one or more revolutions, a process control is performed in which Y, M, and C tone patterns and B tone pattern are transferred onto the sheet conveying belt.
    Type: Application
    Filed: August 27, 2010
    Publication date: March 10, 2011
    Inventors: Hirokatsu SUZUKI, Kazuhisa Sudo, Masanori Kawasumi, Shunichi Hashimoto, Mugijirou Uno, Akira Shinshi, Masaharu Furuya, Masahiko Satoh, Hirohmi Tamura, Kazuya Saitoh, Tomoko Takahashi, Takuya Suganuma
  • Patent number: 7884840
    Abstract: An image forming method and apparatus includes a first image carrying member, a first transfix unit, a second image carrying member, and a second transfix unit. The first image carrying member carries a first toner image thereon. The first transfix unit receives the first toner image from the first image carrying member and transfers and fixes the first toner image onto a first face of a recording sheet with a heat effect. The second image carrying member carries a second toner image thereon. The second transfix unit receives the second toner image from the second image carrying member and transfers and fixes the second toner image onto a second face of the recording sheet with a heat effect.
    Type: Grant
    Filed: July 17, 2006
    Date of Patent: February 8, 2011
    Assignee: Ricoh Co., Ltd.
    Inventors: Norimasa Sohmiya, Chiemi Kaneko, Hirokatsu Suzuki, Kenichi Taguma, Emiko Ishikawa, Yasukuni Omata
  • Publication number: 20110013950
    Abstract: An image forming apparatus includes a first image carrier, a second image carrier, an intermediate transfer member disposed facing the second image carrier, a conveyance belt to transport a transfer sheet, disposed facing both the first image carrier and the intermediate transfer member, a first transfer member to transfer a first toner image formed on the first image carrier onto the transfer sheet, a second transfer member to transfer a second toner image formed on the second image carrier onto the intermediate transfer member, and a third transfer member disposed downstream from the second image carrier in a rotation direction of the intermediate transfer member, to transfer the second toner image from the intermediate transfer member onto the transfer sheet transported by the conveyance belt. The first image carrier and the intermediate transfer member inflect the conveyance belt at a first inflection angle and a second inflection angle, respectively.
    Type: Application
    Filed: July 1, 2010
    Publication date: January 20, 2011
    Inventors: Masaharu FURUYA, Masahiko Satoh, Masanori Kawasumi, Hirokatsu Suzuki, Hirohmi Tamura, Kazuya Saitoh, Takuya Suganuma, Mugijirou Uno, Shunichi Hashimoto, Akira Shinshi, Kazuhisa Sudo, Tomoko Takahashi
  • Publication number: 20100315751
    Abstract: A semiconductor device which combines reliability and the guarantee of electrical characteristics is provided. A power MOSFET and a protection circuit formed over the same semiconductor substrate are provided. The power MOSFET is a trench gate vertical type P-channel MOSFET and the conduction type of the gate electrode is assumed to be P-type. The protection circuit includes a planar gate horizontal type offset P-channel MOSFET and the conduction type of the gate electrode is assumed to be N-type. These gate electrode and gate electrode are formed in separate steps.
    Type: Application
    Filed: August 5, 2010
    Publication date: December 16, 2010
    Applicant: RENESAS ELECTRONICS CORPORATION
    Inventors: Hirokatsu Suzuki, Atsushi Fujiki, Yoshito Nakazawa
  • Patent number: 7835671
    Abstract: A developing device comprises a feeding and conveying path; a stirring and conveying path; and a recovering and conveying path, and capable of extending the service life of a developer and of forming an image with stable image density. In the developing device, the central position of a stirring rotary shaft that is a rotary shaft of a stirring screw and the central position of a feeding rotary shaft that is a rotary shaft of a feed screw are disposed at almost the same height. A recovering rotary shaft that is a rotary shaft of a recovering screw is so disposed that the central position thereof is higher than the central positions of the stirring rotary shaft and feeding rotary shaft, and lower than a rotation central position of the developing rotary shaft that is a rotary shaft of a developing roller.
    Type: Grant
    Filed: July 3, 2007
    Date of Patent: November 16, 2010
    Assignee: Ricoh Company, Ltd.
    Inventor: Hirokatsu Suzuki
  • Patent number: 7796920
    Abstract: A developing unit circulates a developer unidirectionally and includes a developer carrier having a magnetic field generator therein. The developing unit further includes a supply part housing a supply screw, a collecting part housing a collecting screw, an agitation part housing an agitation screw, a first opening, a second opening, and a third opening. The developer is transported by the supply screw, the collecting screw, and the agitation screw from the collecting screw to the agitation screw through the first opening, from the agitation screw to the supply screw through the second opening, and from the supply screw to the collecting screw though the third opening in a developer circulation. A height of a bottom surface of the downstream part of the agitation screw is higher than a height of a bottom surface of the supply screw.
    Type: Grant
    Filed: November 27, 2006
    Date of Patent: September 14, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Kenichi Taguma, Chiemi Kaneko, Hirokatsu Suzuki, Emiko Shiraishi
  • Patent number: 7724394
    Abstract: An image forming apparatus includes a pseudo half tone processing unit that performs a pseudo half tone process on input image data to generate output image data. An exposure unit executes light modulation of a plurality of light emitting sources based on the output image data. The exposure unit performs writing in such a way that different numbers of light emitting sources are used when writing a character/line image and a picture image or a graphics image. The pseudo half tone processing unit performs pseudo half tone processes with different resolutions on a character/line image and a picture image or a graphics image based on the numbers of the light emitting sources to be used for the writing by the exposure unit.
    Type: Grant
    Filed: October 8, 2004
    Date of Patent: May 25, 2010
    Assignee: Ricoh Company, Limited
    Inventors: Kei Yasutomi, Jun Yura, Hideki Kosugi, Hirokatsu Suzuki, Kohichi Katoh, Hiroshi Nakai, Ichiro Kadota, Kazumi Suzuki
  • Publication number: 20100021195
    Abstract: An apparatus and method for image fixing are disclosed. A fixing device includes a fixing member, a pressure member, a heater, and a pressure controller. The fixing member and the pressure member face with each other to form a nip. The heater heats a surface of the fixing member when the fixing member rotates. The pressure controller changes a pressure generated at the nip, according to an operation of the fixing device.
    Type: Application
    Filed: September 30, 2009
    Publication date: January 28, 2010
    Inventors: Jun YURA, Koichi Kato, Hiroshi Nakai, Kazumi Suzuki, Kei Yasutomi, Hideki Kosugi, Hirokatsu Suzuki, Ichiro Kadota
  • Publication number: 20090311006
    Abstract: An image forming apparatus includes an image carrier, a charging unit including a charge member that is disposed facing the image carrier across a gap therebetween and charges the image carrier by using electrical discharge caused by applying thereto a voltage including an alternating current component superimposed on a direct current component, a latent image forming unit, a developing unit to supply toner for developing the latent image formed on the image carrier into a toner image and to collect residual toner remaining on the image carrier, a transfer unit, and a toner spreading member to spread toner on the image carrier and disposed upstream from the charging unit in a direction of movement of the image carrier and downstream from the transfer unit in the direction of movement of the image carrier.
    Type: Application
    Filed: June 10, 2009
    Publication date: December 17, 2009
    Inventors: Emiko SHIRAISHI, Shigekazu Enoki, Jun Yura, Hirokatsu Suzuki
  • Patent number: 7627260
    Abstract: A development apparatus can uniform a toner density by controlling the phase of a toner density fluctuation, and can inhibit fluctuation of the toner density and variation of the toner charge amount. The development apparatus is configured to have a phase control mechanism, which forms a dividing point at a predetermined point (e.g., an opening section provided on a partition plate between two screws) in a flow of a developer within the development apparatus in which a toner density fluctuates spatially due to toner replenishment or toner consumption caused by development, causes the developer divided at the dividing point to pass through different paths (path 1, path 2), thereby shifts a phase of the fluctuation of the toner density within the developer, and thereafter causes thus obtained developers having shifted phases to merge with each other, to perform phase control.
    Type: Grant
    Filed: May 21, 2007
    Date of Patent: December 1, 2009
    Assignee: Ricoh Company, Ltd.
    Inventors: Emiko Shiraishi, Hirokatsu Suzuki
  • Patent number: 7620336
    Abstract: An apparatus including and a method using a fixing device including a fixing member, a pressure member, a heater, and a pressure controller. The fixing member and the pressure member face with each other to form a nip. The heater heats a surface of the fixing member when the fixing member rotates. The pressure controller is configured to change a pressure generated at the nip, according to an operation of the fixing device.
    Type: Grant
    Filed: May 13, 2005
    Date of Patent: November 17, 2009
    Assignee: Ricoh Co., Ltd.
    Inventors: Jun Yura, Koichi Kato, Hiroshi Nakai, Kazumi Suzuki, Kei Yasutomi, Hideki Kosugi, Hirokatsu Suzuki, Ichiro Kadota
  • Patent number: 7593671
    Abstract: A developing device includes a developer bearing member, a developer supplying conveyer, a developer receiving conveyer and a developer agitating conveyer. The developer supplying conveyer or the developer receiving conveyer has at least one dividing position. The dividing position is a position at which the conveying direction of the developer reverses, and a position which is arranged so that if the dividing position is projected to the developer bearing member along a plane which is perpendicular to the widthwise direction of the developer bearing member, the projected position on the developer bearing member is within an area in which the developer is borne on the developer bearing member.
    Type: Grant
    Filed: December 5, 2006
    Date of Patent: September 22, 2009
    Assignee: Ricoh Company, Ltd.
    Inventors: Emiko Ishikawa, Chiemi Kaneko, Hirokatsu Suzuki, Kenichi Taguma
  • Patent number: 7577387
    Abstract: A developing unit for an image forming apparatus including an agent carrying member, a supply compartment, a supply screw, a recovery compartment, a recovery screw, an agitation compartment, and an agitation screw. The agent carrying member carries and supplies developing agent to an image carrying member. The supply screw in the supply compartment supplies the developing agent to the agent carrying member. The recovery screw in the recovery compartment, provided under the agent carrying member, transports the developing agent dropped from the agent carrying member. The agitation screw in the agitation compartment receives the developing agent from the supply compartment and recovery compartment, and transports the developing agent to the supply compartment. The recovery compartment, supply compartment, and agitation compartment are provided side-by-side in a horizontal direction. A magnetic flux density in a given area of the agent carrying member is set to 10 mT or less.
    Type: Grant
    Filed: July 27, 2006
    Date of Patent: August 18, 2009
    Assignee: Ricoh Co., Ltd.
    Inventor: Hirokatsu Suzuki
  • Publication number: 20080124106
    Abstract: A bias voltage-applying unit applies a bias voltage to an insulating toner that includes an electric charge, by making a contact with the insulating toner. A light irradiating unit irradiates the insulating toner with a light. An electric-charge control unit controls an electric charge amount of the insulating toner by causing an optical switch phenomenon in which an electrostatic charge amount of the insulating toner changes, by irradiating the insulating toner with the light using the light irradiating unit while applying the bias voltage to the insulating toner using the bias voltage-applying unit.
    Type: Application
    Filed: November 14, 2007
    Publication date: May 29, 2008
    Inventors: Shigekazu Enoki, Emiko Shiraishi, Hirokatsu Suzuki, Jun Yura, Norimasa Sohmiya
  • Publication number: 20080085137
    Abstract: A developing device comprises a feeding and conveying path; a stirring and conveying path; and a recovering and conveying path, and capable of extending the service life of a developer and of forming an image with stable image density. In the developing device, the central position of a stirring rotary shaft that is a rotary shaft of a stirring screw and the central position of a feeding rotary shaft that is a rotary shaft of a feed screw are disposed at almost the same height. A recovering rotary shaft that is a rotary shaft of a recovering screw is so disposed that the central position thereof is higher than the central positions of the stirring rotary shaft and feeding rotary shaft, and lower than a rotation central position of the developing rotary shaft that is a rotary shaft of a developing roller.
    Type: Application
    Filed: July 3, 2007
    Publication date: April 10, 2008
    Inventor: Hirokatsu SUZUKI
  • Publication number: 20070274741
    Abstract: A development apparatus can uniform a toner density by controlling the phase of a toner density fluctuation, and can inhibit fluctuation of the toner density and variation of the toner charge amount. The development apparatus is configured to have a phase control mechanism, which forms a dividing point at a predetermined point (e.g., an opening section provided on a partition plate between two screws) in a flow of a developer within the development apparatus in which a toner density fluctuates spatially due to toner replenishment or toner consumption caused by development, causes the developer divided at the dividing point to pass through different paths (path 1, path 2), thereby shifts a phase of the fluctuation of the toner density within the developer, and thereafter causes thus obtained developers having shifted phases to merge with each other, to perform phase control.
    Type: Application
    Filed: May 21, 2007
    Publication date: November 29, 2007
    Inventors: Emiko Shiraishi, Hirokatsu Suzuki
  • Publication number: 20070138566
    Abstract: A semiconductor device which combines reliability and the guarantee of electrical characteristics is provided. A power MOSFET and a protection circuit formed over the same semiconductor substrate are provided. The power MOSFET is a trench gate vertical type P-channel MOSFET and the conduction type of the gate electrode is assumed to be P-type. The protection circuit includes a planar gate horizontal type offset P-channel MOSFET and the conduction type of the gate electrode is assumed to be N-type. These gate electrode and gate electrode are formed in separate steps.
    Type: Application
    Filed: December 14, 2006
    Publication date: June 21, 2007
    Inventors: Hirokatsu Suzuki, Atsushi Fujiki, Yoshito Nakazawa
  • Publication number: 20070127951
    Abstract: A developing device includes a developer bearing member, a developer supplying conveyer, a developer receiving conveyer and a developer agitating conveyer. The developer supplying conveyer or the developer receiving conveyer has at least one dividing position. The dividing position is a position at which the conveying direction of the developer reverses, and a position which is arranged so that if the dividing position is projected to the developer bearing member along a plane which is perpendicular to the widthwise direction of the developer bearing member, the projected position on the developer bearing member is within an area in which the developer is borne on the developer bearing member.
    Type: Application
    Filed: December 5, 2006
    Publication date: June 7, 2007
    Inventors: Emiko Ishikawa, Chiemi Kaneko, Hirokatsu Suzuki, Kenichi Taguma
  • Publication number: 20070122202
    Abstract: A developing unit circulates a developer unidirectionally and includes a developer carrier having a magnetic field generator therein. The developing unit further includes a supply part housing a supply screw, a collecting part housing a collecting screw, an agitation part housing an agitation screw, a first opening, a second opening, and a third opening. The developer is transported by the supply screw, the collecting screw, and the agitation screw from the collecting screw to the agitation screw through the first opening, from the agitation screw to the supply screw through the second opening, and from the supply screw to the collecting screw though the third opening in a developer circulation. A height of a bottom surface of the downstream part of the agitation screw is higher than a height of a bottom surface of the supply screw.
    Type: Application
    Filed: November 27, 2006
    Publication date: May 31, 2007
    Inventors: KENICHI TAGUMA, Chiemi Kaneko, Hirokatsu Suzuki, Emiko Shiraishi