Patents by Inventor Hiroki Sasame
Hiroki Sasame 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: 12353144Abstract: A charging device has: a charging member that charges an image bearing member; and a cleaning member that is pressed against the charging member, and that is rubbed against a surface of the charging member by rotating the charging member. The cleaning member includes at least a first layer that contains roughening particles and that comes into contact with the charging member. The Martens hardness of the first layer is higher than that of the surface of the charging member. The roughening particles have a Mohs hardness similar to or higher than that of a component of highest Mohs hardness in toner adhered to the surface of the charging member.Type: GrantFiled: April 9, 2024Date of Patent: July 8, 2025Assignee: CANON KABUSHIKI KAISHAInventors: Hiroki Sasame, Naoki Fuei, Tomoo Akizuki
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Patent number: 11960226Abstract: An image forming apparatus includes a photosensitive member, a developing member to supply a toner to the photosensitive member at a developing portion, and a transfer member to transfer a toner image to a recording material passing through a transfer portion from the photosensitive member. In a case which the transfer is performed to a shorter width recording material and thereafter, the transfer is successively performed to a longer width recording material, a control portion controls a first back contrast formed when an area of a surface of the photosensitive member corresponding to the transfer portion through which the shorter width recording material is passing reaches the developing portion, and a second back contrast formed when an area of the surface corresponding to the transfer portion through which the longer width recording material is passing reaches the developing portion so that the second back contrast is higher than the first back contrast.Type: GrantFiled: November 17, 2022Date of Patent: April 16, 2024Assignee: Canon Kabushiki KaishaInventors: Hiroki Sasame, Tomoo Akizuki
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Publication number: 20230152740Abstract: An image forming apparatus includes a photosensitive member, a developing member to supply a toner to the photosensitive member at a developing portion, a transfer member to transfer a toner image to a recording material passing through a transfer portion from the photosensitive member. In a case which the transfer is performed to a smaller width recording material and thereafter, the transfer is successively performed to a larger width recording material, a control portion controls a first back contrast formed when an area of a surface of the photosensitive member corresponding to the transfer portion through which the smaller width recording material is passing reaches the developing portion, and a second back contrast formed when an area of the surface corresponding to the transfer portion through which the larger width recording material is passing reaches the developing portion so that the second back contrast is larger than the first back contrast.Type: ApplicationFiled: November 17, 2022Publication date: May 18, 2023Inventors: Hiroki Sasame, Tomoo Akizuki
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Patent number: 11500311Abstract: An image forming apparatus includes a controller and a transfer power supply portion configured to output a transfer voltage to a transfer portion so as to transfer a toner image onto a recording material. The transfer power supply portion superimposes a voltage output from a first power supply portion and a voltage output from a second power supply portion to output a superimposed voltage to the transfer portion. The first power supply portion includes a transformer including a primary coil and a secondary coil, and a rectifier circuit portion. The rectifier circuit portion includes a plurality of diodes and a plurality of capacitors. A capacitance of a predetermined capacitor to be charged by a half-wave rectified voltage of an AC voltage generated in the secondary coil is larger than a capacitance of a capacitor to be charged by a voltage higher than the half-wave rectified voltage.Type: GrantFiled: December 14, 2021Date of Patent: November 15, 2022Assignee: Canon Kabushiki KaishaInventors: Hiroki Sasame, Junichi Kubota
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Publication number: 20220197193Abstract: An image forming apparatus includes a controller and a transfer power supply portion configured to output a transfer voltage to a transfer portion so as to transfer the toner image onto the recording material. The transfer power supply portion superimposes a voltage output from a first power supply portion and a voltage output from a second power supply portion to output a superimposed voltage to the transfer portion. The first power supply portion includes a transformer including a primary coil and a secondary coil, and a rectifier circuit portion. The rectifier circuit portion includes a plurality of diodes and a plurality of capacitors. A capacitance of a predetermined capacitor to be charged by a half-wave rectified voltage of an AC voltage generated in the secondary coil is larger than a capacitance of a capacitor to be charged by a voltage higher than the half-wave rectified voltage.Type: ApplicationFiled: December 14, 2021Publication date: June 23, 2022Inventors: Hiroki Sasame, Junichi Kubota
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Patent number: 11360417Abstract: A heater includes a substrate formed of metal into a plate shape in which a length in a longitudinal direction thereof is greater than a length in a short direction thereof when viewed in a thickness direction thereof, an insulating layer formed of insulating material on a first surface of the substrate on a first side in the thickness direction, a heating element arranged on the insulating layer and configured to generate heat by flowing electric current therethrough, and a cover layer arranged to cover the heating element. The heater is a warped shape when receiving no external force, such that a center portion of the heater in the longitudinal direction protrudes to the first side in the thickness direction compared to both end portions of the heater in the longitudinal direction.Type: GrantFiled: February 11, 2021Date of Patent: June 14, 2022Assignee: Canon Kabushiki KaishaInventors: Shoichiro Ikegami, Tomoo Akizuki, Hiroki Sasame, Yusuke Shimizu, Tatsuya Kinukawa
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Patent number: 11275324Abstract: In an image forming apparatus, in a case in which a second toner image to be transferred to a same recording material as a first toner image is to be transferred is formed on the photosensitive member after the first toner image is formed on the photosensitive member and the first toner image is formed on an area of the photosensitive member including at least a part of a position of the second toner image one cycle before with respect to a movement direction of the surface of the photosensitive member, a control unit changes a value of a transfer current at a time of transferring the first toner image to a transfer-receiving member between a first value and a second value of which an absolute value is greater than an absolute value of the first value, based on image information regarding the second toner image.Type: GrantFiled: September 3, 2020Date of Patent: March 15, 2022Assignee: Canon Kabushiki KaishaInventors: Hiroki Sasame, Tomoo Akizuki, Yusuke Shimizu
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Publication number: 20210263454Abstract: A heater includes a substrate formed of metal into a plate shape in which a length in a longitudinal direction thereof is greater than a length in a short direction thereof when viewed in a thickness direction thereof, an insulating layer formed of insulating material on a first surface of the substrate on a first side in the thickness direction, a heating element arranged on the insulating layer and configured to generate heat by flowing electric current therethrough, and a cover layer arranged to cover the heating element. The heater is a warped shape when receiving no external force, such that a center portion of the heater in the longitudinal direction protrudes to the first side in the thickness direction compared to both end portions of the heater in the longitudinal direction.Type: ApplicationFiled: February 11, 2021Publication date: August 26, 2021Inventors: Shoichiro Ikegami, Tomoo Akizuki, Hiroki Sasame, Yusuke Shimizu, Tatsuya Kinukawa
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Publication number: 20210072662Abstract: In an image forming apparatus, in a case in which a second toner image to be transferred to a same recording material as a first toner image is to be transferred is formed on the photosensitive member after the first toner image is formed on the photosensitive member and the first toner image is formed on an area of the photosensitive member including at least a part of a position of the second toner image one cycle before with respect to a movement direction of the surface of the photosensitive member, a control unit changes a value of a transfer current at a time of transferring the first toner image to a transfer-receiving member between a first value and a second value of which an absolute value is greater than an absolute value of the first value, based on image information regarding the second toner image.Type: ApplicationFiled: September 3, 2020Publication date: March 11, 2021Inventors: Hiroki Sasame, Tomoo Akizuki, Yusuke Shimizu
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Patent number: 10386755Abstract: An image forming apparatus includes a discharging device for discharging the drum at a discharging portion opposing the surface of the drum; and a control unit for executing, during non-image formation, a cleaning operation for transferring the toner deposited on the transfer member onto the drum by applying a voltage from transfer voltage source to the transfer member. The control unit does not effect discharge by the discharging device for at least a region of the drum where a transfer voltage for transferring a normal-polarity toner of the toner deposited on the transfer member onto the drum is applied to the transfer member in the cleaning operation, and then passes the region of the drum through the charging portion in a state in which a voltage larger than a surface potential of the drum in a normal polarity side is applied to the charging member.Type: GrantFiled: June 27, 2018Date of Patent: August 20, 2019Assignee: CANON KABUSHIKI KAISHAInventors: Shinsuke Kobayashi, Takaaki Akamatsu, Kenji Shindo, Kohei Okayasu, Hiroki Sasame
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Patent number: 10216112Abstract: An image forming apparatus includes a developing unit which develops a toner image on a surface of a photosensitive member and which collects toner which remains on the surface of the photosensitive member after the developed toner image is transferred to a transfer member. The image forming apparatus includes a controller configured to determine whether a cleaning operation of cleaning the surface of the photosensitive member is to be performed after an image forming operation is performed or control a period of time in which the cleaning operation is performed in accordance with a measured downtime of the image forming apparatus which is a period of time after the image forming operation is terminated and before a next image forming operation is started.Type: GrantFiled: July 18, 2017Date of Patent: February 26, 2019Assignee: Canon Kabushiki KaishaInventors: Hiroki Sasame, Kohei Okayasu, Shinsuke Kobayashi, Takaaki Akamatsu, Kenji Shindo, Takehiko Suzuki, Hironori Kato
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Publication number: 20180307162Abstract: An image forming apparatus includes a discharging device for discharging the drum at a discharging portion opposing the surface of the drum; and a control unit for executing, during non-image formation, a cleaning operation for transferring the toner deposited on the transfer member onto the drum by applying a voltage from transfer voltage source to the transfer member. The control unit does not effect discharge by the discharging device for at least a region of the drum where a transfer voltage for transferring a normal-polarity toner of the toner deposited on the transfer member onto the drum is applied to the transfer member in the cleaning operation, and then passes the region of the drum through the charging portion in a state in which a voltage larger than a surface potential of the drum in a normal polarity side is applied to the charging member.Type: ApplicationFiled: June 27, 2018Publication date: October 25, 2018Inventors: Shinsuke Kobayashi, Takaaki Akamatsu, Kenji Shindo, Kohei Okayasu, Hiroki Sasame
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Patent number: 10073383Abstract: An image forming apparatus includes a discharging device for discharging the drum at a discharging portion opposing the surface of the drum; and a control unit for executing, during non-image formation, a cleaning operation for transferring the toner deposited on the transfer member onto the drum by applying a voltage from transfer voltage source to the transfer member. The control unit does not effect discharge by the discharging device for at least a region of the drum where a transfer voltage for transferring a normal-polarity toner of the toner deposited on the transfer member onto the drum is applied to the transfer member in the cleaning operation, and then passes the region of the drum through the charging portion in a state in which a voltage larger than a surface potential of the drum in a normal polarity side is applied to the charging member.Type: GrantFiled: October 5, 2016Date of Patent: September 11, 2018Assignee: CANON KABUSHIKI KAISHAInventors: Shinsuke Kobayashi, Takaaki Akamatsu, Kenji Shindo, Kohei Okayasu, Hiroki Sasame
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Patent number: 10031446Abstract: An image forming apparatus includes a discharging device for discharging the drum at a discharging portion opposing the surface of the drum; and a control unit for executing, during non-image formation, a cleaning operation for transferring the toner deposited on the transfer member onto the drum by applying a voltage from transfer voltage source to the transfer member. The control unit does not effect discharge by the discharging device for at least a region of the drum where a transfer voltage for transferring a normal-polarity toner of the toner deposited on the transfer member onto the drum is applied to the transfer member in the cleaning operation, and then passes the region of the drum through the charging portion in a state in which a voltage larger than a surface potential of the drum in a normal polarity side is applied to the charging member.Type: GrantFiled: October 5, 2016Date of Patent: July 24, 2018Assignee: CANON KABUSHIKI KAISHAInventors: Shinsuke Kobayashi, Takaaki Akamatsu, Kenji Shindo, Kohei Okayasu, Hiroki Sasame
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Patent number: 10025236Abstract: A relationship 150?Rs (?)/Rm (?)?4000 is established in an environment of a temperature of 15° C. and a humidity of 10% in a case where a surface resistance of a transfer roller is Rs (?) when a current is fed between a pair of electrodes facing each other in an axial direction of the transfer roller and arranged on a surface of the transfer roller with an interval of 5 mm therebetween, the electrodes having a width of 20 mm in a circumferential direction of the transfer roller in a state of being arranged on the transfer roller, and in a case where a combined resistance of a first layer and a second layer is Rm (?) when the current is fed from a core portion to an outer peripheral surface of the second layer.Type: GrantFiled: June 12, 2017Date of Patent: July 17, 2018Assignee: CANON KABUSHIKI KAISHAInventors: Hiroki Sasame, Shinsuke Kobayashi, Takaaki Akamatsu, Kohei Okayasu, Kenji Shindo
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Patent number: 9946216Abstract: An image forming apparatus includes an image bearing member; a developing device; a transfer member; a contact member provided downstream of the transfer member and upstream of the developing device with respect to a movement direction of a surface of the image bearing member and contacting the image bearing member at a contact portion, wherein the surface of the image bearing member passed through a transfer portion reaches the contact portion without being cleaned, a detecting portion for detecting a size of the sheet; and a controller for executing an operation in a cleaning mode for cleaning the contact member. The controller executes the operation in the cleaning mode when the controller discriminates that the size of the sheet detected by the detecting portion is smaller than a size of the toner image.Type: GrantFiled: October 20, 2016Date of Patent: April 17, 2018Assignee: CANON KABUSHIKI KAISHAInventors: Kohei Okayasu, Shinsuke Kobayashi, Takaaki Akamatsu, Kenji Shindo, Hiroki Sasame, Takuya Hayato
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Publication number: 20180024458Abstract: An image forming apparatus includes a developing unit which develops a toner image on a surface of a photosensitive member and which collects toner which remains on the surface of the photosensitive member after the developed toner image is transferred to a transfer member. The image forming apparatus includes a controller configured to determine whether a cleaning operation of cleaning the surface of the photosensitive member is to be performed after an image forming operation is performed or control a period of time in which the cleaning operation is performed in accordance with a measured downtime of the image forming apparatus which is a period of time after the image forming operation is terminated and before a next image forming operation is started.Type: ApplicationFiled: July 18, 2017Publication date: January 25, 2018Inventors: Hiroki Sasame, Kohei Okayasu, Shinsuke Kobayashi, Takaaki Akamatsu, Kenji Shindo, Takehiko Suzuki, Hironori Kato
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Publication number: 20170363993Abstract: A relationship 150?Rs (?)/Rm (?)?4000 is established in an environment of a temperature of 15° C. and a humidity of 10% in a case where a surface resistance of a transfer roller is Rs (?) when a current is fed between a pair of electrodes facing each other in an axial direction of the transfer roller and arranged on a surface of the transfer roller with an interval of 5 mm therebetween, the electrodes having a width of 20 mm in a circumferential direction of the transfer roller in a state of being arranged on the transfer roller, and in a case where a combined resistance of a first layer and a second layer is Rm (?) when the current is fed from a core portion to an outer peripheral surface of the second layer.Type: ApplicationFiled: June 12, 2017Publication date: December 21, 2017Inventors: Hiroki Sasame, Shinsuke Kobayashi, Takaaki Akamatsu, Kohei Okayasu, Kenji Shindo
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Publication number: 20170115622Abstract: An image forming apparatus includes an image bearing member; a developing device; a transfer member; a contact member provided downstream of the transfer member and upstream of the developing device with respect to a movement direction of a surface of the image bearing member and contacting the image bearing member at a contact portion, wherein the surface of the image bearing member passed through a transfer portion reaches the contact portion without being cleaned, a detecting portion for detecting a size of the sheet; and a controller for executing an operation in a cleaning mode for cleaning the contact member. The controller executes the operation in the cleaning mode when the controller discriminates that the size of the sheet detected by the detecting portion is smaller than a size of the toner image.Type: ApplicationFiled: October 20, 2016Publication date: April 27, 2017Inventors: Kohei Okayasu, Shinsuke Kobayashi, Takaaki Akamatsu, Kenji Shindo, Hiroki Sasame, Takuya Hayato
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Publication number: 20170097590Abstract: An image forming apparatus includes a discharging device for discharging the drum at a discharging portion opposing the surface of the drum; and a control unit for executing, during non-image formation, a cleaning operation for transferring the toner deposited on the transfer member onto the drum by applying a voltage from transfer voltage source to the transfer member. The control unit does not effect discharge by the discharging device for at least a region of the drum where a transfer voltage for transferring a normal-polarity toner of the toner deposited on the transfer member onto the drum is applied to the transfer member in the cleaning operation, and then passes the region of the drum through the charging portion in a state in which a voltage larger than a surface potential of the drum in a normal polarity side is applied to the charging member.Type: ApplicationFiled: October 5, 2016Publication date: April 6, 2017Inventors: Shinsuke Kobayashi, Takaaki Akamatsu, Kenji Shindo, Kohei Okayasu, Hiroki Sasame