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).
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Patent number: 7941075Abstract: 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: GrantFiled: June 10, 2009Date of Patent: May 10, 2011Assignee: Ricoh Company, Ltd.Inventors: Emiko Shiraishi, Shigekazu Enoki, Jun Yura, Hirokatsu Suzuki
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Publication number: 20110058832Abstract: 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: ApplicationFiled: August 27, 2010Publication date: March 10, 2011Inventors: Hirokatsu SUZUKI, Kazuhisa Sudo, Masanori Kawasumi, Shunichi Hashimoto, Mugijirou Uno, Akira Shinshi, Masaharu Furuya, Masahiko Satoh, Hirohmi Tamura, Kazuya Saitoh, Tomoko Takahashi, Takuya Suganuma
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Patent number: 7884840Abstract: 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: GrantFiled: July 17, 2006Date of Patent: February 8, 2011Assignee: Ricoh Co., Ltd.Inventors: Norimasa Sohmiya, Chiemi Kaneko, Hirokatsu Suzuki, Kenichi Taguma, Emiko Ishikawa, Yasukuni Omata
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Publication number: 20110013950Abstract: 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: ApplicationFiled: July 1, 2010Publication date: January 20, 2011Inventors: Masaharu FURUYA, Masahiko Satoh, Masanori Kawasumi, Hirokatsu Suzuki, Hirohmi Tamura, Kazuya Saitoh, Takuya Suganuma, Mugijirou Uno, Shunichi Hashimoto, Akira Shinshi, Kazuhisa Sudo, Tomoko Takahashi
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Publication number: 20100315751Abstract: 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: ApplicationFiled: August 5, 2010Publication date: December 16, 2010Applicant: RENESAS ELECTRONICS CORPORATIONInventors: Hirokatsu Suzuki, Atsushi Fujiki, Yoshito Nakazawa
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Patent number: 7835671Abstract: 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: GrantFiled: July 3, 2007Date of Patent: November 16, 2010Assignee: Ricoh Company, Ltd.Inventor: Hirokatsu Suzuki
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Patent number: 7796920Abstract: 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: GrantFiled: November 27, 2006Date of Patent: September 14, 2010Assignee: Ricoh Company, Ltd.Inventors: Kenichi Taguma, Chiemi Kaneko, Hirokatsu Suzuki, Emiko Shiraishi
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Patent number: 7724394Abstract: 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: GrantFiled: October 8, 2004Date of Patent: May 25, 2010Assignee: Ricoh Company, LimitedInventors: Kei Yasutomi, Jun Yura, Hideki Kosugi, Hirokatsu Suzuki, Kohichi Katoh, Hiroshi Nakai, Ichiro Kadota, Kazumi Suzuki
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Publication number: 20100021195Abstract: 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: ApplicationFiled: September 30, 2009Publication date: January 28, 2010Inventors: Jun YURA, Koichi Kato, Hiroshi Nakai, Kazumi Suzuki, Kei Yasutomi, Hideki Kosugi, Hirokatsu Suzuki, Ichiro Kadota
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Publication number: 20090311006Abstract: 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: ApplicationFiled: June 10, 2009Publication date: December 17, 2009Inventors: Emiko SHIRAISHI, Shigekazu Enoki, Jun Yura, Hirokatsu Suzuki
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Patent number: 7627260Abstract: 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: GrantFiled: May 21, 2007Date of Patent: December 1, 2009Assignee: Ricoh Company, Ltd.Inventors: Emiko Shiraishi, Hirokatsu Suzuki
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Patent number: 7620336Abstract: 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: GrantFiled: May 13, 2005Date of Patent: November 17, 2009Assignee: Ricoh Co., Ltd.Inventors: Jun Yura, Koichi Kato, Hiroshi Nakai, Kazumi Suzuki, Kei Yasutomi, Hideki Kosugi, Hirokatsu Suzuki, Ichiro Kadota
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Patent number: 7593671Abstract: 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: GrantFiled: December 5, 2006Date of Patent: September 22, 2009Assignee: Ricoh Company, Ltd.Inventors: Emiko Ishikawa, Chiemi Kaneko, Hirokatsu Suzuki, Kenichi Taguma
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Patent number: 7577387Abstract: 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: GrantFiled: July 27, 2006Date of Patent: August 18, 2009Assignee: Ricoh Co., Ltd.Inventor: Hirokatsu Suzuki
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Publication number: 20080124106Abstract: 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: ApplicationFiled: November 14, 2007Publication date: May 29, 2008Inventors: Shigekazu Enoki, Emiko Shiraishi, Hirokatsu Suzuki, Jun Yura, Norimasa Sohmiya
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Publication number: 20080085137Abstract: 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: ApplicationFiled: July 3, 2007Publication date: April 10, 2008Inventor: Hirokatsu SUZUKI
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Publication number: 20070274741Abstract: 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: ApplicationFiled: May 21, 2007Publication date: November 29, 2007Inventors: Emiko Shiraishi, Hirokatsu Suzuki
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Publication number: 20070138566Abstract: 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: ApplicationFiled: December 14, 2006Publication date: June 21, 2007Inventors: Hirokatsu Suzuki, Atsushi Fujiki, Yoshito Nakazawa
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Publication number: 20070127951Abstract: 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: ApplicationFiled: December 5, 2006Publication date: June 7, 2007Inventors: Emiko Ishikawa, Chiemi Kaneko, Hirokatsu Suzuki, Kenichi Taguma
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Publication number: 20070122202Abstract: 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: ApplicationFiled: November 27, 2006Publication date: May 31, 2007Inventors: KENICHI TAGUMA, Chiemi Kaneko, Hirokatsu Suzuki, Emiko Shiraishi