Patents by Inventor Issei Imamura

Issei Imamura 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).

  • Publication number: 20240085845
    Abstract: A restricting member includes a blade portion and a supporting portion. A contact portion is provided at the blade portion, and, in a cross section orthogonal to a longitudinal direction, the contact portion includes a first portion extending in a first direction and a second portion extending toward a free end from an end of the first portion and extending in a second direction. When a region demarcated by connecting an intersection point, the end of the first portion, and an end of the second portion by a straight line is defined as a first region, the intersection point being where an imaginary line intersects an extension line of the first portion in the first direction, an area of the first region is smaller on a longitudinal end portion than on a longitudinal central portion of the blade portion.
    Type: Application
    Filed: November 20, 2023
    Publication date: March 14, 2024
    Inventors: Issei Imamura, Ryohei Tsutsumi, Yuichiro Hirata, Takuya Oka
  • Patent number: 11860565
    Abstract: A restricting member includes a blade portion and a supporting portion. A contact portion is provided at the blade portion, and, in a cross section orthogonal to a longitudinal direction, the contact portion includes a first portion extending in a first direction and a second portion extending toward a free end from an end of the first portion and extending in a second direction. When a region demarcated by connecting an intersection point, the end of the first portion, and an end of the second portion by a straight line is defined as a first region, the intersection point being where an imaginary line intersects an extension line of the first portion in the first direction, an area of the first region is smaller on a longitudinal end portion than on a longitudinal central portion of the blade portion.
    Type: Grant
    Filed: June 23, 2022
    Date of Patent: January 2, 2024
    Assignee: Canon Kabushiki Kaisha
    Inventors: Issei Imamura, Ryohei Tsutsumi, Yuichiro Hirata, Takuya Oka
  • Patent number: 11693335
    Abstract: A cartridge mountable in an apparatus main body of an image forming apparatus, the cartridge includes a development roller, a frame member including a development chamber, a developer containing chamber, and a first opening portion, the developer containing chamber including an inner wall and a second opening portion, a stirring member including a stirring shaft and a sheet, and a conveyance member driven in such a manner that the developer is replenished into the developer containing chamber through the second opening portion, wherein the sheet is rotated in contact with the inner wall in such a manner that, after the sheet is elastically deformed by contact with a portion of the inner wall, at least a part of the elastic deformation is restored, and wherein the conveyance member is being driven at a timing when the sheet passes through the front side.
    Type: Grant
    Filed: March 2, 2022
    Date of Patent: July 4, 2023
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takuya Oka, Issei Imamura, Ryohei Tsutsumi, Keitaro Nakata
  • Publication number: 20230010866
    Abstract: An image forming apparatus comprising an image bearing member, a developer bearing member, a drive unit for driving the image bearing member and the developer bearing member in varied peripheral speeds, a control unit, a developing voltage application unit, a supply member for supplying a developer to the developer bearing member, and, a supply member voltage application unit, wherein the control unit executes a first image forming mode in which a rotational peripheral speed ratio between surface movement speeds of the developer bearing member and the image bearing member is not more than 1 and a second image forming mode in which the rotational peripheral speed ratio is larger than 1, and, the control unit controls the drive unit so that a difference between developing voltage and supply voltage becomes larger in the second image forming mode than in the first image forming mode.
    Type: Application
    Filed: July 1, 2022
    Publication date: January 12, 2023
    Inventors: Kodai Hayashi, Issei Imamura, Shinichi Agata, Takuya Oka
  • Publication number: 20220413425
    Abstract: A restricting member includes a blade portion and a supporting portion. A contact portion is provided at the blade portion, and, in a cross section orthogonal to a longitudinal direction, the contact portion includes a first portion extending in a first direction and a second portion extending toward a free end from an end of the first portion and extending in a second direction. When a region demarcated by connecting an intersection point, the end of the first portion, and an end of the second portion by a straight line is defined as a first region, the intersection point being where an imaginary line intersects an extension line of the first portion in the first direction, an area of the first region is smaller on a longitudinal end portion than on a longitudinal central portion of the blade portion.
    Type: Application
    Filed: June 23, 2022
    Publication date: December 29, 2022
    Inventors: Issei Imamura, Ryohei Tsutsumi, Yuichiro Hirata, Takuya Oka
  • Patent number: 11513449
    Abstract: An image forming apparatus detects a first current value and a second current value of currents flowing between an image bearing member and a developer carrying member. When a difference between the detected first current value and the detected second current value exceeds a threshold in a state in which the image bearing member and the developer carrying member are rotated and a first developing voltage is applied to the developer carrying member, a controller controls AC voltage applied to the developer carrying member.
    Type: Grant
    Filed: November 19, 2020
    Date of Patent: November 29, 2022
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Naoki Fukushima, Nobuyoshi Yoshida, Issei Imamura, Shunsuke Matsushita, Yosuke Kishi
  • Publication number: 20220187739
    Abstract: A cartridge mountable in an apparatus main body of an image forming apparatus, the cartridge includes a development roller, a frame member including a development chamber, a developer containing chamber, and a first opening portion, the developer containing chamber including an inner wall and a second opening portion, a stirring member including a stirring shaft and a sheet, and a conveyance member driven in such a manner that the developer is replenished into the developer containing chamber through the second opening portion, wherein the sheet is rotated in contact with the inner wall in such a manner that, after the sheet is elastically deformed by contact with a portion of the inner wall, at least a part of the elastic deformation is restored, and wherein the conveyance member is being driven at a timing when the sheet passes through the front side.
    Type: Application
    Filed: March 2, 2022
    Publication date: June 16, 2022
    Inventors: Takuya Oka, Issei Imamura, Ryohei Tsutsumi, Keitaro Nakata
  • Patent number: 11360405
    Abstract: An electrophotographic apparatus comprising an electrophotographic photosensitive member, a charging device and a developing device, wherein the charging device comprises a conductive member arranged to be capable of contacting the electrophotographic photosensitive member, the conductive layer at the outer surface of the conductive member comprises a matrix and a plurality of domains dispersed in the matrix, at least some of the domains are exposed at the outer surface of the conductive member, the matrix has a volume resistivity R1 of larger than 1.00×1012 ?·cm, the volume resistivity R1 of the matrix is 1.0×105 times or more a volume resistivity R2 of the domains, the developing device comprises the toner comprising a toner particle and a silica fine particle, and a coverage ratio of the toner surface with the silica fine particles is from 62.0% by area to 100.0% by area as determined by X-ray photoelectron spectroscopy.
    Type: Grant
    Filed: October 15, 2020
    Date of Patent: June 14, 2022
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Hiroyuki Tomono, Yoshitaka Suzumura, Takuya Mizuguchi, Osamu Matsushita, Masahiro Kurachi, Kazuhiro Yamauchi, Issei Imamura
  • Patent number: 11300900
    Abstract: A cartridge mountable in an apparatus main body of an image forming apparatus, the cartridge includes a development roller, a frame member including a development chamber, a developer containing chamber, and a first opening portion, the developer containing chamber including an inner wall and a second opening portion, a stirring member including a stirring shaft and a sheet, and a conveyance member driven in such a manner that the developer is replenished into the developer containing chamber through the second opening portion, wherein the sheet is rotated in contact with the inner wall in such a manner that, after the sheet is elastically deformed by contact with a portion of the inner wall, at least a part of the elastic deformation is restored, and wherein the conveyance member is being driven at a timing when the sheet passes through the front side.
    Type: Grant
    Filed: May 21, 2021
    Date of Patent: April 12, 2022
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takuya Oka, Issei Imamura, Ryohei Tsutsumi, Keitaro Nakata
  • Publication number: 20210373462
    Abstract: A cartridge mountable in an apparatus main body of an image forming apparatus, the cartridge includes a development roller, a frame member including a development chamber, a developer containing chamber, and a first opening portion, the developer containing chamber including an inner wall and a second opening portion, a stirring member including a stirring shaft and a sheet, and a conveyance member driven in such a manner that the developer is replenished into the developer containing chamber through the second opening portion, wherein the sheet is rotated in contact with the inner wall in such a manner that, after the sheet is elastically deformed by contact with a portion of the inner wall, at least a part of the elastic deformation is restored, and wherein the conveyance member is being driven at a timing when the sheet passes through the front side.
    Type: Application
    Filed: May 21, 2021
    Publication date: December 2, 2021
    Inventors: Takuya Oka, Issei Imamura, Ryohei Tsutsumi, Keitaro Nakata
  • Publication number: 20210173321
    Abstract: An image forming apparatus includes a rotatable image bearing member, a charging member, a rotatable developer carrying member, a developing voltage applying portion, a detecting portion for detecting a first current value and a second current value of currents flowing between the image bearing member and the developer carrying member, and a controller for controlling the applying portion. When a difference between the first current value and the second current value which are detected by the detecting portion exceeds a threshold in a state in which the image bearing member and the developer carrying member are rotated and the developing voltage is applied to the developer carrying member, the controller controls the AC voltage of the developing voltage applied to the developer carrying member.
    Type: Application
    Filed: November 19, 2020
    Publication date: June 10, 2021
    Inventors: Naoki Fukushima, Nobuyoshi Yoshida, Issei Imamura, Shunsuke Matsushita, Yosuke Kishi
  • Publication number: 20210116829
    Abstract: An electrophotographic apparatus comprising an electrophotographic photosensitive member, a charging device and a developing device, wherein the charging device comprises a conductive member arranged to be capable of contacting the electrophotographic photosensitive member, the conductive layer at the outer surface of the conductive member comprises a matrix and a plurality of domains dispersed in the matrix, at least some of the domains are exposed at the outer surface of the conductive member, the matrix has a volume resistivity R1 of larger than 1.00×1012 ?·cm, the volume resistivity R1 of the matrix is 1.0×105 times or more a volume resistivity R2 of the domains, the developing device comprises the toner comprising a toner particle and a silica fine particle, and a coverage ratio of the toner surface with the silica fine particles is from 62.0% by area to 100.0% by area as determined by X-ray photoelectron spectroscopy.
    Type: Application
    Filed: October 15, 2020
    Publication date: April 22, 2021
    Inventors: Hiroyuki Tomono, Yoshitaka Suzumura, Takuya Mizuguchi, Osamu Matsushita, Masahiro Kurachi, Kazuhiro Yamauchi, Issei Imamura
  • Patent number: 10175599
    Abstract: One end portion and the other end portion of a rotating member, which face each other and form a joint portion, have a shape with projections and recesses. Projections of one end portion fit in recesses of the other end portion, while projections of the other end portion fit in recesses of the one end portion, so that the one end portion and the other end portion are interlocked. The projections have a first corner portion rounded in an arc, while the recesses have a second corner portion rounded in an arc in which the first corner portion fits. The first corner portion has a larger radius of curvature than that of the second corner portion.
    Type: Grant
    Filed: June 22, 2017
    Date of Patent: January 8, 2019
    Assignee: Canon Kabushiki Kaisha
    Inventors: Fumito Nonaka, Makoto Hayashida, Hiroomi Matsuzaki, Hiraku Sasaki, Issei Imamura, Koji Yamaguchi
  • Patent number: 10088794
    Abstract: An image forming apparatus includes a rotatably supported photosensitive drum, a charging roller configured to charge the photosensitive drum, a developing sleeve configured to develop an electrostatic latent image formed on a surface of the photosensitive drum and collect toner adhered to the photosensitive drum, an electricity removal sheet disposed on a downstream from the charging roller in a direction of movement on a surface of the photosensitive drum and disposed on an upstream side from the developing sleeve and arranged in contact with the photosensitive drum, and an electricity removal high-voltage power supply configured to apply voltage to the electricity removal sheet. The electricity removal high-voltage power supply an image-forming period applies a DC bias having a polarity identical to a charging polarity of the photosensitive drum and having a lower absolute value than that of the charged potential of the photosensitive drum to electricity removal sheet.
    Type: Grant
    Filed: May 9, 2017
    Date of Patent: October 2, 2018
    Assignee: Canon Kabushiki Kaisha
    Inventor: Issei Imamura
  • Patent number: 9996020
    Abstract: A cylindrical shaft of a roller has facing surfaces which form a depression-protrusion-shaped portion of a joint of the cylindrical shaft and which face or make contact with each other and moreover which extend in a direction non-parallel to an axial direction of the cylindrical shaft, and the facing surfaces are inclined at a predetermined engagement angle with respect to a circumferential direction. A generating line of a circumferential surface of a coating layer that coats an outer circumference of the cylindrical shaft and a generating line of a circumferential surface of a photosensitive drum cross each other at a crossing angle smaller than the engagement angle.
    Type: Grant
    Filed: June 15, 2017
    Date of Patent: June 12, 2018
    Assignee: Canon Kabushiki Kaisha
    Inventors: Makoto Hayashida, Hiroomi Matsuzaki, Fumito Nonaka, Hiraku Sasaki, Issei Imamura, Koji Yamaguchi
  • Publication number: 20170371263
    Abstract: A cylindrical shaft of a roller has facing surfaces which form a depression-protrusion-shaped portion of a joint of the cylindrical shaft and which face or make contact with each other and moreover which extend in a direction non-parallel to an axial direction of the cylindrical shaft, and the facing surfaces are inclined at a predetermined engagement angle with respect to a circumferential direction. A generating line of a circumferential surface of a coating layer that coats an outer circumference of the cylindrical shaft and a generating line of a circumferential surface of a photosensitive drum cross each other at a crossing angle smaller than the engagement angle.
    Type: Application
    Filed: June 15, 2017
    Publication date: December 28, 2017
    Inventors: Makoto Hayashida, Hiroomi Matsuzaki, Fumito Nonaka, Hiraku Sasaki, Issei Imamura, Koji Yamaguchi
  • Publication number: 20170371264
    Abstract: One end portion and the other end portion of a rotating member, which face each other and form a joint portion, have a shape with projections and recesses. Projections of one end portion fit in recesses of the other end portion, while projections of the other end portion fit in recesses of the one end portion, so that the one end portion and the other end portion are interlocked. The projections have a first corner portion rounded in an arc, while the recesses have a second corner portion rounded in an arc in which the first corner portion fits. The first corner portion has a larger radius of curvature than that of the second corner portion.
    Type: Application
    Filed: June 22, 2017
    Publication date: December 28, 2017
    Inventors: Fumito Nonaka, Makoto Hayashida, Hiroomi Matsuzaki, Hiraku Sasaki, Issei Imamura, Koji Yamaguchi
  • Publication number: 20170329271
    Abstract: An image forming apparatus includes a rotatably supported photosensitive drum, a charging roller configured to charge the photosensitive drum, a developing sleeve configured to develop an electrostatic latent image formed on a surface of the photosensitive drum and collect toner adhered to the photosensitive drum, an electricity removal sheet disposed on a downstream from the charging roller in a direction of movement on a surface of the photosensitive drum and disposed on an upstream side from the developing sleeve and arranged in contact with the photosensitive drum, and an electricity removal high-voltage power supply configured to apply voltage to the electricity removal sheet. The electricity removal high-voltage power supply an image-forming period applies a DC bias having a polarity identical to a charging polarity of the photosensitive drum and having a lower absolute value than that of the charged potential of the photosensitive drum to electricity removal sheet.
    Type: Application
    Filed: May 9, 2017
    Publication date: November 16, 2017
    Inventor: Issei Imamura
  • Patent number: 9086642
    Abstract: A blade-like charging member for charging a surface of an image bearing member. The blade-like charging member includes a charging portion for effecting electric discharge to the surface of the image bearing member and a non-charging portion. The non-charging portion can contact the image bearing member with a gap. At least a part of the non-charging portion is made of a material having a higher resistance than that of the charging portion so as to prevent electric discharge between the non-charging portion and the surface of the image bearing member. The non-charging portion is capable of sliding contact with the surface of the image bearing member over the entirety of an image forming region width of the surface of the image bearing member. The charge portion and the non-charging portion are bonded to each other by adhesive material at a connection interface.
    Type: Grant
    Filed: December 8, 2011
    Date of Patent: July 21, 2015
    Assignee: Canon Kabushiki Kaisha
    Inventor: Issei Imamura
  • Publication number: 20120148308
    Abstract: A blade-like charging member for charging a surface of an image bearing member by contacting thereto includes a charging portion for effecting electric discharge to the surface of the image bearing member. The non-charging portion is made of a material having a higher resistance than that of the charging portion so as to prevent electric discharge between the non-charging portion and the surface of the image bearing member. The non-charging portion is capable of sliding contact with the surface of the image bearing member over the entirety of an image forming region width of the surface of the image bearing member, the charge non-charging portions are bonded to each other by adhesive material at a connection interface.
    Type: Application
    Filed: December 8, 2011
    Publication date: June 14, 2012
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Issei Imamura