Patents by Inventor Yoshiko Ogawa

Yoshiko Ogawa 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: 9921541
    Abstract: A developing device includes a developer bearer to carry, by rotation, developer including toner and magnetic carrier to a developing range facing a latent image bearer; a casing including a developer container and an opening to expose a part of the developer bearer disposed in the casing; an opposing face of the casing including a conductive material and opposing to a surface of the developer bearer downstream from the developing range in a direction of rotation of the developer bearer; a developing bias source to apply a developing bias to the developer bearer; and an insulation layer disposed on the opposing face of the casing. The opposing face is disposed across, from the developer bearer, a casing gap sized to allow the developer borne on the developer bearer to contact the opposing face.
    Type: Grant
    Filed: May 22, 2015
    Date of Patent: March 20, 2018
    Assignee: RICOH COMPANY, LTD.
    Inventors: Yasunobu Shimizu, Akira Azami, Masaaki Yamada, Yoshiko Ogawa, Toshio Koike, Mutsuki Morinaga, Yutaka Takahashi, Keinosuke Kondoh, Kentaro Mikuniya, Yoshiharu Kishi
  • Patent number: 9772579
    Abstract: A developing device includes a developer bearer disposed facing a latent image bearer in a developing range to transport developer by rotation, a support to support the developer bearer and including a holder mount, a rod-shaped developer regulator disposed facing a surface of the developer bearer across a gap, and a holder secured to the holder mount of the support to hold the rod-shaped developer regulator. The rod-shaped developer regulator extends in an axial direction of the developer bearer.
    Type: Grant
    Filed: December 30, 2016
    Date of Patent: September 26, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Yuki Oshikawa, Akira Azami, Yoshiko Ogawa, Masaaki Yamada, Yoshihiro Fujiwara, Noriyuki Kimura, Yoshiharu Kishi, Yasunobu Shimizu, Junichi Matsumoto, Yoshiyuki Fukuda, Yuuji Ishikura, Kei Saito
  • Publication number: 20170108795
    Abstract: A developing device includes a developer bearer disposed facing a latent image hearer in a developing range to transport developer by rotation, a support to support the developer bearer and including a holder mount, a rod-shaped developer regulator disposed facing a surface of the developer bearer across a gap, and a holder secured to the holder mount of the support to hold the rod-shaped developer regulator. The rod-shaped developer regulator extends in an axial direction of the developer bearer.
    Type: Application
    Filed: December 30, 2016
    Publication date: April 20, 2017
    Inventors: Yuki OSHIKAWA, Akira Azami, Yoshiko Ogawa, Masaaki Yamada, Yoshihiro Fujiwara, Noriyuki Kimura, Yoshiharu Kishi, Yasunobu Shimizu, Junichi Matsumoto, Yoshiyuki Fukuda, Yuuji Ishikura, Kei Saito
  • Patent number: 9625851
    Abstract: A developing device includes a developer bearer disposed facing a latent image bearer in a developing range to transport developer by rotation, a support to support the developer bearer and including a holder mount, a rod-shaped developer regulator disposed facing a surface of the developer bearer across a gap, and a holder secured to the holder mount of the support to hold the rod-shaped developer regulator. The rod-shaped developer regulator extends in an axial direction of the developer bearer.
    Type: Grant
    Filed: February 1, 2016
    Date of Patent: April 18, 2017
    Assignee: Ricoh Company, Ltd.
    Inventors: Yuki Oshikawa, Akira Azami, Yoshiko Ogawa, Masaaki Yamada, Yoshihiro Fujiwara, Noriyuki Kimura, Yoshiharu Kishi, Yasunobu Shimizu, Junichi Matsumoto, Yoshiyuki Fukuda, Yuuji Ishikura, Kei Saito
  • Publication number: 20160238966
    Abstract: A developing device includes a developer bearer disposed facing a latent image bearer in a developing range to transport developer by rotation, a support to support the developer bearer and including a holder mount, a rod-shaped developer regulator disposed facing a surface of the developer bearer across a gap, and a holder secured to the holder mount of the support to hold the rod-shaped developer regulator. The rod-shaped developer regulator extends in an axial direction of the developer bearer.
    Type: Application
    Filed: February 1, 2016
    Publication date: August 18, 2016
    Inventors: Yuki OSHIKAWA, Akira AZAMI, Yoshiko OGAWA, Masaaki YAMADA, Yoshihiro FUJIWARA, Noriyuki KIMURA, Yoshiharu KISHI, Yasunobu SHIMIZU, Junichi MATSUMOTO, Yoshiyuki FUKUDA, Yuuji ISHIKURA, Kei SAITO
  • Patent number: 9201336
    Abstract: A developing device including: a toner bearing member configured to bear a toner on a surface of the toner bearing member and configured such that the surface thereof is rotated to supply the toner to and develop a latent electrostatic image on a surface of a latent electrostatic image bearing member in a developing region which faces the latent electrostatic image bearing member; and a regulating member configured to regulate an amount of the toner to be moved towards the developing region, wherein the surface of the toner bearing member has regularly arranged convex portions, and wherein a non-electrostatic adhesive force between the toner and the surface of the toner bearing member is less than 9.0 nN.
    Type: Grant
    Filed: February 6, 2013
    Date of Patent: December 1, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Osamu Endou, Yasuyuki Ishii, Yoshiko Ogawa, Yuuji Ishikura, Hideyasu Seki, Toshio Koike, Akihiro Kawakami
  • Publication number: 20150338824
    Abstract: A developing device includes a developer bearer to carry, by rotation, developer including toner and magnetic carrier to a developing range facing a latent image bearer; a casing including a developer container and an opening to expose a part of the developer bearer disposed in the casing; an opposing face of the casing including a conductive material and opposing to a surface of the developer bearer downstream from the developing range in a direction of rotation of the developer bearer; a developing bias source to apply a developing bias to the developer bearer; and an insulation layer disposed on the opposing face of the casing. The opposing face is disposed across, from the developer bearer, a casing gap sized to allow the developer borne on the developer bearer to contact the opposing face.
    Type: Application
    Filed: May 22, 2015
    Publication date: November 26, 2015
    Applicant: RICOH COMPANY, LTD.
    Inventors: Yasunobu Shimizu, Akira Azami, Masaaki Yamada, Yoshiko Ogawa, Toshio Koike, Mutsuki Morinaga, Yutaka Takahashi, Keinosuke Kondoh, Kentaro Mikuniya, Yoshiharu Kishi
  • Patent number: 9158228
    Abstract: A development device includes a developer bearer to carry by rotation developer to a development range facing a latent image bearer, and a planar metal developer regulator to adjust an amount of developer carried by the developer bearer to the development range. The developer bearer includes a developer carrying range having surface unevenness, and the developer regulator includes a fixed end portion held by a regulator holder and a free end portion to contact a surface of the developer bearer.
    Type: Grant
    Filed: September 10, 2012
    Date of Patent: October 13, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Yoshiko Ogawa, Osamu Endou, Yasuyuki Ishii, Yuuji Ishikura, Hideyasu Seki, Tetsuro Hirota
  • Patent number: 8965254
    Abstract: A development device includes a developer bearer to carry by rotation developer to a development range facing a latent image bearer and a developer regulator to adjust an amount of developer transported to the development range by the developer bearer. The developer bearer includes a developer carrying range having surface unevenness; and a surface of the developer bearer is coated with a coating material including a resin material and particles to roughen the surface.
    Type: Grant
    Filed: December 28, 2012
    Date of Patent: February 24, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Yoshiko Ogawa, Yasuyuki Ishii, Osamu Endou, Yuuji Ishikura
  • Patent number: 8948638
    Abstract: An image forming apparatus includes a latent image carrier; a latent image writer to write a latent image on the latent image carrier; a developing unit including a toner carrier having first and second electrodes insulated via an insulator member and a voltage applying unit to apply voltages to the first and second electrodes having a potential difference to generate first electric fields to cause the toner to hop from the toner carrier to the latent image carrier to develop a toner image; and a transfer unit to transfer the developed toner image to a transferring member. When alternating voltages having a same phase and same amplitude are applied to the first and second electrodes to form second electric fields between the latent image carrier and the toner carrier, the toner is discharged from the toner carrier to the latent image carrier in a toner discharge mode.
    Type: Grant
    Filed: August 23, 2011
    Date of Patent: February 3, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Yuji Ishikura, Yasuyuki Ishii, Hideki Kosugi, Tetsuro Hirota, Masaaki Yamada, Yoshiko Ogawa, Atsushi Kurokawa, Hideyasu Seki, Masanori Horike, Shin Kayahara
  • Patent number: 8929782
    Abstract: A development device includes a developer bearer to carry by rotation developer to a development range facing a latent image bearer, and a developer regulator to adjust an amount of developer transported to the development range by the developer bearer. Multiple projections are formed in a surface of the developer bearer, and, in a direction in which the developer bearer rotates, a downstream end of each of the multiple projections is higher than an upstream end of the projection.
    Type: Grant
    Filed: December 31, 2012
    Date of Patent: January 6, 2015
    Assignee: Ricoh Company, Ltd.
    Inventors: Osamu Endou, Yasuyuki Ishii, Tetsuro Hirota, Yoshiko Ogawa, Atsushi Kurokawa, Yuuji Ishikura, Hideyasu Seki
  • Patent number: 8594540
    Abstract: A development device includes a toner carrier including first and second groups of electrodes, a toner supplier, and an electrical field generator. The electrical field generator includes a positive-phase pulse voltage generation circuit, a negative-phase pulse voltage generation circuit, a first DC power source for supplying a bias for setting a peak value of pulse voltages, a second DC power source to output a variable voltage having a polarity identical to a polarity of toner charge, a first diode having an anode connected to a lower potential side of the first DC power source and a cathode connected to an output terminal of the positive-phase pulse voltage generation circuit, and a second diode having an anode connected to the lower potential side of the first DC power source and a cathode connected to an output terminal of the negative-phase pulse voltage generation circuit.
    Type: Grant
    Filed: January 14, 2011
    Date of Patent: November 26, 2013
    Assignee: Ricoh Company, Limited
    Inventors: Tetsuro Hirota, Hideki Kosugi, Yoshiko Ogawa, Atsushi Kurokawa, Hideyasu Seki, Masaaki Yamada, Yuji Ishikura
  • Patent number: 8588635
    Abstract: A development device includes a developer container, a rotary developer carrier that is disposed facing the latent image carrier and including multiple outer electrodes arranged in a circumferential direction of the developer carrier, an inner electrode electrically insulated from the multiple outer electrodes, an insulation layer disposed between the inner and outer electrodes, and a surface layer overlaying the outer electrodes and electrically insulating the multiple outer electrodes from each other, a bias power source to generate electrical fields that change with time by applying a first and second bias voltages to the inner and outer electrodes, respectively, an electrical field adjuster to regulate the electrical fields in accordance with a thickness of the surface layer of the developer carrier, and a controller.
    Type: Grant
    Filed: December 29, 2010
    Date of Patent: November 19, 2013
    Assignee: Ricoh Company, Limited
    Inventors: Yoshiko Ogawa, Yasuyuki Ishii, Hideki Kosugi, Masaaki Yamada, Atsushi Kurokawa, Yuji Ishikura
  • Publication number: 20130216250
    Abstract: A development device includes a developer bearer to carry by rotation developer to a development range facing a latent image bearer, and a developer regulator to adjust an amount of developer transported to the development range by the developer bearer. Multiple projections are formed in a surface of the developer bearer, and the developer bearer rotates in a reverse direction to a direction of rotation for image development while image development is not performed. The developer regulator includes a blade having a first end held by a regulator holder and a second end that contacts the multiple projections formed in the surface of the developer bearer and is disposed in a direction counter to the direction of rotation of the developer bearer for image development.
    Type: Application
    Filed: January 24, 2013
    Publication date: August 22, 2013
    Inventors: Hideyasu SEKI, Yasuyuki Ishii, Yoshiko Ogawa, Osamu Endou, Yuuji Ishikura, Masayuki Yamane, Keiichi Yoshida, Atsushi Kurokawa, Masahiro Watanabe, Akihiro Kawakami
  • Publication number: 20130216277
    Abstract: A development device includes a developer bearer to carry by rotation developer to a development range facing a latent image bearer, and a developer regulator to adjust an amount of developer transported to the development range by the developer bearer. Multiple projections are formed in a surface of the developer bearer, and, in a direction in which the developer bearer rotates, a downstream end of each of the multiple projections is higher than an upstream end of the projection.
    Type: Application
    Filed: December 31, 2012
    Publication date: August 22, 2013
    Inventors: Osamu ENDOU, Yasuyuki ISHII, Tetsuro HIROTA, Yoshiko OGAWA, Atsushi KUROKAWA, Yuuji ISHIKURA, Hideyasu SEKI
  • Publication number: 20130216278
    Abstract: A development device includes a developer bearer to carry by rotation developer to a development range facing a latent image bearer, and a developer regulator to contact the developer bearer and adjust an amount of developer transported to the development range by the developer bearer. Multiple projections are formed in a surface of the developer bearer. The developer regulator has an end face, an opposed face facing the developer bearer, and an edge face connecting the opposed face to the end face, and the edge face of the developer regulator contacts the developer bearer.
    Type: Application
    Filed: January 24, 2013
    Publication date: August 22, 2013
    Inventor: Yoshiko OGAWA
  • Publication number: 20130216276
    Abstract: A development device includes a developer bearer to carry by rotation developer to a development range facing a latent image bearer and a developer regulator to adjust an amount of developer transported to the development range by the developer bearer. The developer bearer includes a developer carrying range having surface unevenness; and a surface of the developer bearer is coated with a coating material including a resin material and particles to roughen the surface.
    Type: Application
    Filed: December 28, 2012
    Publication date: August 22, 2013
    Inventors: Yoshiko OGAWA, Yasuyuki Ishii, Osamu Endou, Yuuji Ishikura
  • Publication number: 20130209143
    Abstract: A developing device including: a toner bearing member configured to bear a toner on a surface of the toner bearing member and configured such that the surface thereof is rotated to supply the toner to and develop a latent electrostatic image on a surface of a latent electrostatic image bearing member in a developing region which faces the latent electrostatic image bearing member; and a regulating member configured to regulate an amount of the toner to be moved towards the developing region, wherein the surface of the toner bearing member has regularly arranged convex portions, and wherein a non-electrostatic adhesive force between the toner and the surface of the toner bearing member is less than 9.0 nN.
    Type: Application
    Filed: February 6, 2013
    Publication date: August 15, 2013
    Inventors: Osamu ENDOU, Yasuyuki ISHII, Yoshiko OGAWA, Yuuji ISHIKURA, Hideyasu SEKI, Toshio KOIKE, Akihiro KAWAKAMI
  • Patent number: 8433211
    Abstract: A disclosed developing device includes a toner carrying member having electrodes, a toner supply unit supplying the toner to the toner carrying member, and a hopping electric field generator unit generating electric field to cause the toner hopping on the toner carrying member by applying a pulse voltage to the electrodes. The hopping electric field generator unit includes a pulse voltage generator circuit generating the pulse voltage, a first direct-current power source supplying bias to the pulse voltage generator circuit for regulating a peak value of the pulse voltage, and a second direct-current power source having a same polarity with a toner charging polarity, and outputting a variable voltage level. The hopping electric field generator unit controls the peak value of the pulse voltage by changing an output of the first power source and a mean thereof by changing an output of the second power source.
    Type: Grant
    Filed: September 10, 2010
    Date of Patent: April 30, 2013
    Assignee: Ricoh Company, Ltd.
    Inventors: Masanori Horike, Tetsuro Hirota, Atsushi Kurokawa, Hideki Kosugi, Masaaki Yamada, Yoshiko Ogawa, Yuji Ishikura
  • Publication number: 20130071148
    Abstract: A development device includes a developer bearer to carry by rotation developer to a development range facing a latent image bearer, a planar developer regulator disposed to contact a surface of the developer bearer to adjust an amount of developer carried to the development range, and a lateral end seal to contact an axial end portion of the developer bearer. The developer bearer includes an uneven surface range having projections and recesses and including an axial center of the developer bearer and smooth surface ranges positioned outside the uneven surface range in an axial direction of the developer bearer, and the lateral end seal is disposed astride the uneven surface range and the smooth surface range of the developer bearer.
    Type: Application
    Filed: September 10, 2012
    Publication date: March 21, 2013
    Inventors: Yuuji ISHIKURA, Yasuyuki ISHII, Osamu ENDOU, Yoshiko OGAWA, Katsuhiro AOKI, Masaaki YAMADA, Masayuki YAMANE, Atsushi KUROKAWA, Yuuki SATOH