Patents by Inventor Shintaro Yamada

Shintaro Yamada 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: 7831182
    Abstract: A disclosed developing device includes a developing roller; a supply roller that is in contact with the developing roller and configured to supply toner to the developing roller; a current measuring unit configured to measure an electric current that flows from the developing roller to the supply roller when the toner is supplied from the supply roller to the developing roller; and an error determining unit configured to detect a development error of the developing roller based on the electric current measured by the current measuring unit.
    Type: Grant
    Filed: April 8, 2008
    Date of Patent: November 9, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Rumi Konishi, Kenji Asuwa, Yoshiko Ogawa, Shuuichi Nakagawa, Ryuji Inoue, Shin Murayama, Kazushige Oonishi, Shintaro Yamada
  • Publication number: 20100150609
    Abstract: A semiconductive member including an alkali metal salt having the formula (M)n·X in a surface layer thereof. M represents Na+, K+, or Li+; X represents Cl?, Br?, I?, F?, CH3COO?, CF3COO?, CH(COOH)CHCOO?, (CHCOO?)2, CH2(COOH)CH2COO?, (CH2COO?)2, (HOOC)Ar(COO?), Ar(COO?)2, (HOOC)2Ar(COO?), (HOOC)Ar(COO?)2, Ar(COO?)3, (HOOC)3Ar(COO?), (HOOC)2Ar(COO?)2, (HOOC)Ar (COO?)3, Ar(COO?)4, Ar—SO3?, Ar(SO3?)2, an oligomer or a polymer having an acrylic acid anion unit, or an oligomer or a polymer having an methacrylic acid anion unit; Ar represents a benzene ring, a naphthalene ring, or a biphenyl ring; and n is a numeral equivalent to the anionic valence of X.
    Type: Application
    Filed: November 20, 2009
    Publication date: June 17, 2010
    Inventors: Chiyoshi Nozaki, Tetsumaru Fujita, Shintaro Yamada, Yuji Nagatomo, Shin Murayama, Manabu Hamada, Yoshimichi Ishikawa
  • Patent number: 7680443
    Abstract: A developing device is provided with which the increase in torque of a supply roller, unevenness of image density, and wear to the supply roller caused by the formation of an aggregated block of toner in the gap between the supply roller and the opposing side wall of a supply developer holding chamber can be suppressed.
    Type: Grant
    Filed: February 9, 2007
    Date of Patent: March 16, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Shin Murayama, Shuuichi Nakagawa, Ryuji Inoue, Shintaro Yamada
  • Patent number: 7676184
    Abstract: A developing apparatus is disclosed that includes a developer carrier for carrying a developer used for developing a latent image, a developer supplying chamber having a developer supplying member for supplying the developer to the developer carrier by rotation, a developer storing chamber positioned above the developer supplying chamber for storing the developer and supplying the developer to the developer supplying chamber, and a partitioning member positioned between the developer supplying chamber and the developer storing chamber. The partitioning member has an opening through which the developer is supplied from the developer storing chamber to the developer supplying chamber. The developing apparatus includes a conveying member positioned above the partitioning member for conveying the developer in a substantially horizontal direction.
    Type: Grant
    Filed: November 30, 2007
    Date of Patent: March 9, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Shin Murayama, Shuuichi Nakagawa, Ryuji Inoue, Yuji Nagatomo, Shintaro Yamada, Kazushige Oonishi, Hirobumi Ooyoshi, Tomofumi Yoshida
  • Publication number: 20100028057
    Abstract: A developing device develops an electrostatic latent image formed on an image carrier with toner. The developing device includes a developer carrier, a developer supplying unit that supplies a developer on the developer carrier, a layer shaping member that shapes the developer supplied on the developer carrier into a thin layer, and an electric-field control member that is arranged downstream of a shaping nip formed between the developer carrier and the layer shaping member and that controls an intensity of an electric field generated between the developer carrier and the layer shaping member.
    Type: Application
    Filed: July 21, 2009
    Publication date: February 4, 2010
    Inventors: Shintaro YAMADA, Shin MURAYAMA, Ryuji INOUE, Shuuichi NAKAGAWA, Kazushige OHNISHI
  • Patent number: 7634213
    Abstract: In a toner collecting device of the present invention for conveying collected waste toner to a waste toner storing portion with a toner conveying device, the toner conveying device is positioned at a side opposite to a driveline included in an apparatus body to which the toner collecting device is mounted. A driveline for driving the toner conveying device is not arranged at the side opposite to the driveline of the apparatus body, but the toner conveying device is directly driven by the driveline of the apparatus body. With this configuration, the toner collecting device is capable of driving, e.g., a toner conveying belt or a toner conveying screw arranged at the counter drive side without sophisticating the configuration.
    Type: Grant
    Filed: October 31, 2006
    Date of Patent: December 15, 2009
    Assignee: Ricoh Company, Ltd.
    Inventors: Tomofumi Yoshida, Yoshiyuki Shimizu, Kenzo Tatsumi, Hirobumi Ooyoshi, Shintaro Yamada
  • Publication number: 20090208252
    Abstract: A developing device that can reliably supply toner from a toner supply roller to a developing roller and that does not generate scraping irregularities in the toner thin layer on the developing roller, and a process cartridge and an image forming apparatus having the same. The developing device has: a toner supply chamber; a developing roller provided in the toner supply chamber; a toner supply roller provided in the toner supply chamber for supplying toner to the developing roller; and a layer regulation member for forming the toner on the developing roller into a thin layer, and develops electrostatic latent images on an image carrier by applying bias voltage to the developing roller. An intermediate contact member is interposed between the developing roller and the toner supply roller.
    Type: Application
    Filed: February 4, 2009
    Publication date: August 20, 2009
    Inventors: Shuuichi Nakagawa, Ryuji Inoue, Shin Murayama, Kazushige Ohnishi, Shintaro Yamada
  • Publication number: 20090041512
    Abstract: A developing device for developing an electrostatic latent image on an image carrier by supplying a one-component developer to the image carrier. Good images can be obtained over long periods of time, without printing history becoming apparent on account of residual developer. The developing device has a developer carrier that is rotatable and disposed facing an image carrier; and a conductive developer supply and recovery member rotatably arranged so as to abut the developer carrier. The rotation direction of the conductive developer supply and recovery member is opposite to the rotation direction of the developer carrier at a position where the developer carrier and the conductive developer supply and recovery member abut each other. A contact pressure P between the developer carrier and the conductive developer supply and recovery member is set so as to satisfy the relationship 0 (kPa)<P<5.0 (kPa).
    Type: Application
    Filed: July 24, 2008
    Publication date: February 12, 2009
    Inventors: Shin MURAYAMA, Shuichi Nakagawa, Ryuji Inoue, Shintaro Yamada
  • Patent number: 7460804
    Abstract: An image forming apparatus includes detecting means for detecting a toner image formed on an image carrier, and transport means for transporting a sheet. The detecting means is disposed on an inner side in a width of the image carrier, and on an outer side of a contact region with the transport means and the sheet, in a direction perpendicular to a transporting direction of the sheet.
    Type: Grant
    Filed: December 22, 2004
    Date of Patent: December 2, 2008
    Assignee: Ricoh Printing Systems, Ltd.
    Inventors: Atsushi Onose, Tatsunari Sato, Shintaro Yamada
  • Publication number: 20080280225
    Abstract: An image developing method is disclosed that is able to efficiently remove degraded toner on a developing agent carrier, prevent formation of abnormal images, ensure good image quality over time, and increase the service life of the device. The developing method includes a step of calculating an amount of consumption of the developing agent during image formation and an amount of consumption of the developing agent in a compulsory toner consumption mode under different calculation conditions between the image formation and the compulsory toner consumption mode. In the compulsory toner consumption mode, a developing bias different from a developing bias used during image formation is applied for a predetermined time period to discharge residual developing agent on a developing agent carrier to a latent image carrier.
    Type: Application
    Filed: April 28, 2008
    Publication date: November 13, 2008
    Inventors: Rumi KONISHI, Shuuichi Nakagawa, Ryuji Inoue, Shin Murayama, Kazushige Oonishi, Shintaro Yamada
  • Publication number: 20080267641
    Abstract: A disclosed developing device includes a developing roller; a supply roller that is in contact with the developing roller and configured to supply toner to the developing roller; a current measuring unit configured to measure an electric current that flows from the developing roller to the supply roller when the toner is supplied from the supply roller to the developing roller; and an error determining unit configured to detect a development error of the developing roller based on the electric current measured by the current measuring unit.
    Type: Application
    Filed: April 8, 2008
    Publication date: October 30, 2008
    Inventors: Rumi Konishi, Kenji Asuwa, Yoshiko Ogawa, Shuuichi Nakagawa, Ryuji Inoue, Shin Murayama, Kazushige Oonishi, Shintaro Yamada
  • Publication number: 20080175626
    Abstract: A developing device that prevents the formation of agglomerated masses of developing agent in the bottom of the developing agent housing chamber near the developing roller and the supply roller, and that maintains the fluidity of the developing agent in the bottom of the developing agent housing chamber, while minimizing any increase in size of the developing device.
    Type: Application
    Filed: December 27, 2007
    Publication date: July 24, 2008
    Inventors: Shin Murayama, Shuuichi Nakagawa, Ryuji Inoue, Shintaro Yamada
  • Publication number: 20080145109
    Abstract: A developing apparatus is disclosed that includes a developer carrier for carrying a developer used for developing a latent image, a developer supplying chamber having a developer supplying member for supplying the developer to the developer carrier by rotation, a developer storing chamber positioned above the developer supplying chamber for storing the developer and supplying the developer to the developer supplying chamber, and a partitioning member positioned between the developer supplying chamber and the developer storing chamber. The partitioning member has an opening through which the developer is supplied from the developer storing chamber to the developer supplying chamber. The developing apparatus includes a conveying member positioned above the partitioning member for conveying the developer in a substantially horizontal direction.
    Type: Application
    Filed: November 30, 2007
    Publication date: June 19, 2008
    Inventors: Shin MURAYAMA, Shuuichi Nakagawa, Ryuji Inoue, Yuji Nagatomo, Shintaro Yamada, Kazushige Oonishi, Hirobumi Ooyoshi, Tomofumi Yoshida
  • Publication number: 20080131174
    Abstract: A developer regulating member capable of stably regulating the thickness of a developer even when used for a long time, while preventing the increase in the production cost, a developing device having the developer regulating member, an image forming apparatus having the developing device, a process cartridge, and a method of producing the developer regulating member. The average crystal particle diameter D [?m] of a plate-like member provided in a layer-thinning blade which functions as the developer regulating member and which abuts against a developing roller functioning as a developer carrier, and the curvature radius R [?m] of a bent portion satisfy the relationship of D?60.53×R×10?3?12.61.
    Type: Application
    Filed: November 29, 2007
    Publication date: June 5, 2008
    Inventors: Ryuji INOUE, Shuuichi Nakagawa, Shin Murayama, Rumi Konishi, Shintaro Yamada, Kazushige Oonishi
  • Publication number: 20070189812
    Abstract: A developing device is provided with which the increase in torque of a supply roller, unevenness of image density, and wear to the supply roller caused by the formation of an aggregated block of toner in the gap between the supply roller and the opposing side wall of a supply developer holding chamber can be suppressed.
    Type: Application
    Filed: February 9, 2007
    Publication date: August 16, 2007
    Inventors: Shin Murayama, Shuuichi Nakagawa, Ryuji Inoue, Shintaro Yamada
  • Patent number: 7227562
    Abstract: Provided is a small-sized electrophotographic apparatus for which maintenance such as disposal of a jam of sheets, replacement of consumables including toner, or replacement of components to be periodically replaced can be facilitated.
    Type: Grant
    Filed: October 29, 2003
    Date of Patent: June 5, 2007
    Assignee: Ricoh Printing Systems, Ltd.
    Inventors: Kenji Asuwa, Toru Miyasaka, Taichiro Yamashita, Masahiro Yagi, Shintaro Yamada
  • Patent number: 7224915
    Abstract: An image forming apparatus comprising: an image forming section and a residual toner amount detection unit. The image forming section includes a photosensitive member, a charging unit, an exposure unit, a developing unit, and a toner storage unit. The residual toner amount detection unit detects an amount of toner remaining in the developing unit. The residual toner amount detection unit includes a light-emitting element and a light-receiving element. After the toner is deposited on the photosensitive member to form a toner image until electric charge is given onto a photosensitive layer of the photosensitive member by the charging unit again, the light-emitting element removes electric charge remaining on the photosensitive layer.
    Type: Grant
    Filed: March 6, 2006
    Date of Patent: May 29, 2007
    Assignee: Ricoh Printing Systems, Ltd.
    Inventors: Shintaro Yamada, Kenji Asuwa, Susumu Tateyama, Hirobumi Ooyoshi, Tomofumi Yoshida
  • Publication number: 20070104523
    Abstract: In a toner collecting device of the present invention for conveying collected waste toner to a waste toner storing portion with a toner conveying device, the toner conveying device is positioned at a side opposite to a driveline included in an apparatus body to which the toner collecting device is mounted. A driveline for driving the toner conveying device is not arranged at the side opposite to the driveline of the apparatus body, but the toner conveying device is directly driven by the driveline of the apparatus body. With this configuration, the toner collecting device is capable of driving, e.g., a toner conveying belt or a toner conveying screw arranged at the counter drive side without sophisticating the configuration.
    Type: Application
    Filed: October 31, 2006
    Publication date: May 10, 2007
    Inventors: Tomofumi Yoshida, Yoshiyuki Shimizu, Kenzo Tatsumi, Hirobumi Ooyoshi, Shintaro Yamada
  • Patent number: 7215896
    Abstract: An image forming apparatus is able to form steady test-pattern toner images for calibration of reflection density detection characteristics with ample toner. The operation consists of forming a test-pattern toner image for calibration of the reflection density detection characteristics, which is formed of a plurality of toner images of different colors aside from a reference test-pattern toner image for controlling image forming conditions, detecting the detection characteristics of a reflection density sensor from the result of detection of the quantity of toner attached to the test-pattern toner image for calibration of the reflection density detection characteristics, and calibrating the output characteristics of the reflection density sensor.
    Type: Grant
    Filed: July 29, 2004
    Date of Patent: May 8, 2007
    Assignee: Ricoh Printing Systems, Ltd.
    Inventors: Shintaro Yamada, Akira Shimada, Tatsunari Sato, Nobuaki Fukasawa, Satoshi Narita
  • Patent number: 7209681
    Abstract: An electrophotographic apparatus includes a plurality of image forming devices, wherein each image forming device includes a developing device having a tip end part and a toner storage part coupled to the tip end part. A thickness of the tip end part is smaller than a thickness of the toner storage part. An exposure device, which is an LED array, is arranged near the tip end part.
    Type: Grant
    Filed: October 30, 2003
    Date of Patent: April 24, 2007
    Assignee: Ricoh Printing Systems, Ltd.
    Inventors: Shintaro Yamada, Toru Miyasaka, Taichiro Yamashita, Kenji Asuwa, Masahiro Yagi