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).
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Patent number: 11073773Abstract: 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: GrantFiled: September 25, 2020Date of Patent: July 27, 2021Assignee: TOSHIBA TEC KABUSHIKI KAISHAInventors: Mitsutoshi Watanabe, Hirotaka Fukuyama
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Publication number: 20200301315Abstract: 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: ApplicationFiled: March 20, 2019Publication date: September 24, 2020Inventors: Masayuki Kasukawa, Hirotaka Fukuyama
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Publication number: 20190041772Abstract: 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: ApplicationFiled: October 11, 2018Publication date: February 7, 2019Inventors: Hirotaka FUKUYAMA, Sunao TAKENAKA
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Patent number: 10126687Abstract: 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: GrantFiled: December 29, 2016Date of Patent: November 13, 2018Assignees: KABUSHIKI KAISHA TOSHIBA, TOSHIBA TEC KABUSHIKI KAISHAInventors: Hirotaka Fukuyama, Sunao Takenaka
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Publication number: 20180188671Abstract: 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: ApplicationFiled: December 29, 2016Publication date: July 5, 2018Inventors: Hirotaka FUKUYAMA, Sunao TAKENAKA
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Patent number: 8121526Abstract: 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: GrantFiled: December 29, 2010Date of Patent: February 21, 2012Assignees: Kabushiki Kaisha Toshiba, Toshiba Tec Kabushiki KaishaInventors: Hirotaka Fukuyama, Koichiro Sato
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Publication number: 20110274452Abstract: 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: ApplicationFiled: April 28, 2011Publication date: November 10, 2011Applicants: TOSHIBA TEC KABUSHIKI KAISHA, KABUSHIKI KAISHA TOSHIBAInventors: Hirotaka Fukuyama, Sunao Takenaka
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Publication number: 20110143272Abstract: 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: ApplicationFiled: December 7, 2010Publication date: June 16, 2011Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA TEC KABUSHIKI KAISHAInventors: Shingo Urasawa, Hirotaka Fukuyama
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Patent number: 7962074Abstract: 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: GrantFiled: February 17, 2009Date of Patent: June 14, 2011Assignees: Kabushiki Kaisha Toshiba, Toshiba Tec Kabushiki KaishaInventors: Hirotaka Fukuyama, Satoshi Itaya
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Publication number: 20110091234Abstract: 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: ApplicationFiled: December 29, 2010Publication date: April 21, 2011Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA TEC KABUSHIKI KAISHAInventors: Hirotaka Fukuyama, Koichiro Sato
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Publication number: 20110064430Abstract: 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: ApplicationFiled: August 31, 2010Publication date: March 17, 2011Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA TEC KABUSHIKI KAISHAInventors: Hiromichi Mitamura, Hirotaka Fukuyama, Sunao Takenaka
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Patent number: 7885589Abstract: 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: GrantFiled: June 22, 2009Date of Patent: February 8, 2011Assignees: Kabushiki Kaisha Toshiba, Toshiba Tec Kabushiki KaishaInventors: Hirotaka Fukuyama, Koichiro Sato
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Publication number: 20100266303Abstract: 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: ApplicationFiled: April 16, 2010Publication date: October 21, 2010Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA TEC KABUSHIKI KAISHAInventors: Hirotaka Fukuyama, Satoshi Itaya
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Publication number: 20090257765Abstract: 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: ApplicationFiled: June 22, 2009Publication date: October 15, 2009Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA TEC KABUSHIKI KAISHAInventors: Hirotaka FUKUYAMA, Koichiro SATO
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Publication number: 20090232556Abstract: 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: ApplicationFiled: March 11, 2009Publication date: September 17, 2009Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA TEC KABUSHIKI KAISHAInventors: Hirotaka Fukuyama, Satoshi Itaya
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Publication number: 20090208254Abstract: 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: ApplicationFiled: February 17, 2009Publication date: August 20, 2009Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA TEC KABUSHIKI KAISHAInventors: Hirotaka Fukuyama, Satoshi Itaya
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Patent number: 7570908Abstract: 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: GrantFiled: May 2, 2007Date of Patent: August 4, 2009Assignees: Kabuhsiki Kaisha Toshiba, Toshiba Tec Kabushiki KaishaInventors: Hirotaka Fukuyama, Koichiro Sato
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Publication number: 20070286625Abstract: 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: ApplicationFiled: May 2, 2007Publication date: December 13, 2007Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA TEC KABUSHIKI KAISHAInventors: Hirotaka Fukuyama, Koichiro Sato
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Patent number: 6744995Abstract: 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: GrantFiled: October 24, 2002Date of Patent: June 1, 2004Assignees: Kabushiki Kaisha Toshiba, Toshiba Tec Kabushiki KaishaInventors: Hirotaka Fukuyama, Koichiro Sato
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Publication number: 20040081474Abstract: 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: ApplicationFiled: October 24, 2002Publication date: April 29, 2004Applicant: TOSHIBA TEC KABUSHIKI KAISHAInventors: Hirotaka Fukuyama, Koichiro Sato