Patents by Inventor Hirotaka Fukuyama

Hirotaka Fukuyama 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: 11073773
    Abstract: According to one embodiment, the image forming apparatus includes a developing device and a control unit. The developing device includes a rotator for rotating to cause a developer contained in a container to flow, and performs development using the developer. The control unit has a first control for rotating the rotator in a first direction during development. The control unit has a second control that rotates the rotator in a second direction opposite to the first direction at a predetermined timing when development is not performed. When the second control is performed a plurality of times during a predetermined period, the control unit gradually reduces an interval at which the second control is performed.
    Type: Grant
    Filed: September 25, 2020
    Date of Patent: July 27, 2021
    Assignee: TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Mitsutoshi Watanabe, Hirotaka Fukuyama
  • Publication number: 20200301315
    Abstract: According to one embodiment, a developing device includes a developer storage unit, a magnet roller, a first stirring screw, and a second stirring screw. The developer storage unit is configured to be made to be able to circulate and convey a developer. The first stirring screw conveys the developer from a second opening portion to a first opening portion along a longitudinal direction. The first stirring screw includes a rotating shaft and a protrusive ridge. The protrusive ridge spirally swirls around the rotating shaft. A plurality of notches are formed in part of the protrusive ridge. The phases of the plurality of notches in the circumferential direction of the rotating shaft at respective central positions in the plurality of notches are shifted in the axial direction. The second stirring screw conveys the developer from the first opening portion to the second opening portion along the longitudinal direction.
    Type: Application
    Filed: March 20, 2019
    Publication date: September 24, 2020
    Inventors: Masayuki Kasukawa, Hirotaka Fukuyama
  • Publication number: 20190041772
    Abstract: An image forming apparatus according to an embodiment includes an image forming unit that forms a toner image on an image carrier body. A primary transfer member transfers the toner image formed on the image carrier body onto an intermediate transfer body. A secondary transfer member transfers the toner image from the intermediate transfer body onto a recording medium. A control unit applies a cleaning bias to the secondary transfer member while an idle operation of the secondary transfer member is being performed before the toner image is secondarily transferred onto the transferring target material.
    Type: Application
    Filed: October 11, 2018
    Publication date: February 7, 2019
    Inventors: Hirotaka FUKUYAMA, Sunao TAKENAKA
  • Patent number: 10126687
    Abstract: An image forming apparatus according to an embodiment includes an image forming unit that forms a toner image on an image carrier body. A primary transfer member transfers the toner image formed on the image carrier body onto an intermediate transfer body. A secondary transfer member transfers the toner image from the intermediate transfer body onto a recording medium. A control unit applies a cleaning bias to the secondary transfer member while an idle operation of the secondary transfer member is being performed before the toner image is secondarily transferred onto the transferring target material.
    Type: Grant
    Filed: December 29, 2016
    Date of Patent: November 13, 2018
    Assignees: KABUSHIKI KAISHA TOSHIBA, TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Hirotaka Fukuyama, Sunao Takenaka
  • Publication number: 20180188671
    Abstract: An image forming apparatus according to an embodiment includes an image forming unit that forms a toner image on an image carrier body. A primary transfer member transfers the toner image formed on the image carrier body onto an intermediate transfer body. A secondary transfer member transfers the toner image from the intermediate transfer body onto a recording medium. A control unit applies a cleaning bias to the secondary transfer member while an idle operation of the secondary transfer member is being performed before the toner image is secondarily transferred onto the transferring target material.
    Type: Application
    Filed: December 29, 2016
    Publication date: July 5, 2018
    Inventors: Hirotaka FUKUYAMA, Sunao TAKENAKA
  • Patent number: 8121526
    Abstract: A technique capable of preventing deterioration of image quality resulting from a band-shaped toner image created on a photosensitive surface in order to prevent so-called carrier attraction is provided. An image forming method involving an abutting and separation step that allows a first image carrier (YMC) and a second image carrier (K) to abut on an intermediate transfer body to form an image and thereafter that allows only the second image carrier to abut on the intermediate transfer body by separating the first image carrier from the intermediate transfer body; and then a collecting step that collects a toner band on the first image carrier in situ to conduct new image formation.
    Type: Grant
    Filed: December 29, 2010
    Date of Patent: February 21, 2012
    Assignees: Kabushiki Kaisha Toshiba, Toshiba Tec Kabushiki Kaisha
    Inventors: Hirotaka Fukuyama, Koichiro Sato
  • Publication number: 20110274452
    Abstract: According to one embodiment, an image forming apparatus includes an image bearing member, a developing device, a cleaning executing section, and a potential adjusting section. An electrostatic latent image is formed on the image bearing member. The developing device stores a two-component developer including a toner and a carrier, includes a toner carrying member, which carries the two-component developer, arranged to be opposed to the image bearing member, and forms a toner image corresponding to the electrostatic latent image on the surface of the image bearing member. The cleaning executing section performs cleaning of the image bearing member. The potential adjusting section adjusts, during the cleaning, development contrast potential, which is a potential difference between the electrostatic latent image potential of the image bearing member and the potential of the developing device, such that the carrier adheres to the image bearing member together with the toner.
    Type: Application
    Filed: April 28, 2011
    Publication date: November 10, 2011
    Applicants: TOSHIBA TEC KABUSHIKI KAISHA, KABUSHIKI KAISHA TOSHIBA
    Inventors: Hirotaka Fukuyama, Sunao Takenaka
  • Publication number: 20110143272
    Abstract: According to an embodiment, an image forming apparatus includes an image holding member, a plurality of image forming units, an image density detection unit, an image density comparison unit, a control unit, a developer residual amount acquisition unit, and an image stabilization kind determination unit. The plurality of image forming units include at least a developer of a first color and a developer of a second color and form a predetermined pattern image on the image holding member using the developers of the first and second colors. The developer residual amount acquisition unit acquires a residual amount of the developer of the second color.
    Type: Application
    Filed: December 7, 2010
    Publication date: June 16, 2011
    Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Shingo Urasawa, Hirotaka Fukuyama
  • Patent number: 7962074
    Abstract: A suction duct that sucks air is provided downstream from a magnet roller that applies a developer to a photoconductor while rotating, in a direction of rotation of the photoconductor, and upstream of a surface potential sensor that measures surface potential of the photoconductor. Moreover, ribs for adjusting an air flow are arranged within the suction duct in such a manner that a width of an air flow passage formed by a rear end in a direction of air flow and a forward end of a nearest rib in the direction of air flow is narrowed from a rib installed upstream in the direction of air flow toward a rib installed downstream. The collection duct collects a floating developer by using a negative pressure.
    Type: Grant
    Filed: February 17, 2009
    Date of Patent: June 14, 2011
    Assignees: Kabushiki Kaisha Toshiba, Toshiba Tec Kabushiki Kaisha
    Inventors: Hirotaka Fukuyama, Satoshi Itaya
  • Publication number: 20110091234
    Abstract: A technique capable of preventing deterioration of image quality resulting from a band-shaped toner image created on a photosensitive surface in order to prevent so-called carrier attraction is provided. An image forming method involving an abutting and separation step that allows a first image carrier (YMC) and a second image carrier (K) to abut on an intermediate transfer body to form an image and thereafter that allows only the second image carrier to abut on the intermediate transfer body by separating the first image carrier from the intermediate transfer body; and then a collecting step that collects a toner band on the first image carrier in situ to conduct new image formation.
    Type: Application
    Filed: December 29, 2010
    Publication date: April 21, 2011
    Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Hirotaka Fukuyama, Koichiro Sato
  • Publication number: 20110064430
    Abstract: In an image forming method, an execution condition of forcible toner consumption is obtained based on an environmental value at a time of final image formation and a present environmental value, the forcible toner consumption is executed under the execution condition, and image formation is performed after calibration.
    Type: Application
    Filed: August 31, 2010
    Publication date: March 17, 2011
    Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Hiromichi Mitamura, Hirotaka Fukuyama, Sunao Takenaka
  • Patent number: 7885589
    Abstract: A technique capable of preventing deterioration of image quality resulting from a band-shaped toner image created on a photosensitive surface in order to prevent so-called carrier attraction is provided. An image forming method involving an abutting and separation step that allows a first image carrier (YMC) and a second image carrier (K) to abut on an intermediate transfer body to form an image and thereafter that allows only the second image carrier to abut on the intermediate transfer body by separating the first image carrier from the intermediate transfer body; and then a collecting step that collects a toner band on the first image carrier in situ to conduct new image formation.
    Type: Grant
    Filed: June 22, 2009
    Date of Patent: February 8, 2011
    Assignees: Kabushiki Kaisha Toshiba, Toshiba Tec Kabushiki Kaisha
    Inventors: Hirotaka Fukuyama, Koichiro Sato
  • Publication number: 20100266303
    Abstract: According to one embodiment, an image forming apparatus configured to form an image and record the image on a recording material includes a driving unit configured to drive plural color developing devices and a black developing device independent from one another, a toner quantity meter configured to measure toner residual quantities in the developing devices after development processing applied to photoconductive members, a toner supplying unit configured to execute operation for supplying the toners to the respective developing devices according to the measured toner residual quantities, and a controller configured to start, with reference to timing when the toner supply operation is completed last in the plural color developing devices, operation for stopping the plural color developing devices and start, with reference to timing when the black toner supply operation is completed, operation for stopping the black developing device.
    Type: Application
    Filed: April 16, 2010
    Publication date: October 21, 2010
    Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Hirotaka Fukuyama, Satoshi Itaya
  • Publication number: 20090257765
    Abstract: A technique capable of preventing deterioration of image quality resulting from a band-shaped toner image created on a photosensitive surface in order to prevent so-called carrier attraction is provided. An image forming method involving an abutting and separation step that allows a first image carrier (YMC) and a second image carrier (K) to abut on an intermediate transfer body to form an image and thereafter that allows only the second image carrier to abut on the intermediate transfer body by separating the first image carrier from the intermediate transfer body; and then a collecting step that collects a toner band on the first image carrier in situ to conduct new image formation.
    Type: Application
    Filed: June 22, 2009
    Publication date: October 15, 2009
    Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Hirotaka FUKUYAMA, Koichiro SATO
  • Publication number: 20090232556
    Abstract: A driving time count is obtained by accumulating a multiplication value which is obtained by multiplying a driving time of a mixer by a coefficient corresponding to an operation of a developing roller. When the driving time count reaches a life threshold for judgment of a life of a developer, it is judged that the developer reaches its end of life.
    Type: Application
    Filed: March 11, 2009
    Publication date: September 17, 2009
    Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Hirotaka Fukuyama, Satoshi Itaya
  • Publication number: 20090208254
    Abstract: A suction duct that sucks air is provided downstream from a magnet roller that applies a developer to a photoconductor while rotating, in a direction of rotation of the photoconductor, and upstream of a surface potential sensor that measures surface potential of the photoconductor. Moreover, ribs for adjusting an air flow are arranged within the suction duct in such a manner that a width of an air flow passage formed by a rear end in a direction of air flow and a forward end of a nearest rib in the direction of air flow is narrowed from a rib installed upstream in the direction of air flow toward a rib installed downstream. The collection duct collects a floating developer by using a negative pressure.
    Type: Application
    Filed: February 17, 2009
    Publication date: August 20, 2009
    Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Hirotaka Fukuyama, Satoshi Itaya
  • Patent number: 7570908
    Abstract: A technique capable of preventing deterioration of image quality resulting from a band-shaped toner image created on a photosensitive surface in order to prevent so-called carrier attraction is provided.
    Type: Grant
    Filed: May 2, 2007
    Date of Patent: August 4, 2009
    Assignees: Kabuhsiki Kaisha Toshiba, Toshiba Tec Kabushiki Kaisha
    Inventors: Hirotaka Fukuyama, Koichiro Sato
  • Publication number: 20070286625
    Abstract: A technique capable of preventing deterioration of image quality resulting from a band-shaped toner image created on a photosensitive surface in order to prevent so-called carrier attraction is provided.
    Type: Application
    Filed: May 2, 2007
    Publication date: December 13, 2007
    Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Hirotaka Fukuyama, Koichiro Sato
  • Patent number: 6744995
    Abstract: A high image quality electrophotographic image forming apparatus is provided without increasing the size and cost, and reducing the life thereof. The potential difference (contrast potential) between a photoreceptor and a development roller for supplying toner to the photoreceptor by the use of a carrier is set to be smaller in the non-image area irrelevant to the printing operation, and set to be larger in the image area relevant to the printing operation. In this manner, the damage to the photoreceptor caused by the adhesion of the carrier is reduced in the non-image area irrelevant to the printing operation, and the fog is reduced in the image area relevant to the printing operation.
    Type: Grant
    Filed: October 24, 2002
    Date of Patent: June 1, 2004
    Assignees: Kabushiki Kaisha Toshiba, Toshiba Tec Kabushiki Kaisha
    Inventors: Hirotaka Fukuyama, Koichiro Sato
  • Publication number: 20040081474
    Abstract: A high image quality electrophotographic image forming apparatus is provided without increasing the size and cost, and reducing the life thereof. The potential difference (contrast potential) between a photoreceptor and a development roller for supplying toner to the photoreceptor by the use of a carrier is set to be smaller in the non-image area irrelevant to the printing operation, and set to be larger in the image area relevant to the printing operation. In this manner, the damage to the photoreceptor caused by the adhesion of the carrier is reduced in the non-image area irrelevant to the printing operation, and the fog is reduced in the image area relevant to the printing operation.
    Type: Application
    Filed: October 24, 2002
    Publication date: April 29, 2004
    Applicant: TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Hirotaka Fukuyama, Koichiro Sato