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).

  • Patent number: 12353144
    Abstract: 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: Grant
    Filed: April 9, 2024
    Date of Patent: July 8, 2025
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Hiroki Sasame, Naoki Fuei, Tomoo Akizuki
  • Patent number: 11960226
    Abstract: 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: Grant
    Filed: November 17, 2022
    Date of Patent: April 16, 2024
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hiroki Sasame, Tomoo Akizuki
  • Publication number: 20230152740
    Abstract: 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: Application
    Filed: November 17, 2022
    Publication date: May 18, 2023
    Inventors: Hiroki Sasame, Tomoo Akizuki
  • Patent number: 11500311
    Abstract: 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: Grant
    Filed: December 14, 2021
    Date of Patent: November 15, 2022
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hiroki Sasame, Junichi Kubota
  • Publication number: 20220197193
    Abstract: 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: Application
    Filed: December 14, 2021
    Publication date: June 23, 2022
    Inventors: Hiroki Sasame, Junichi Kubota
  • Patent number: 11360417
    Abstract: 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: Grant
    Filed: February 11, 2021
    Date of Patent: June 14, 2022
    Assignee: Canon Kabushiki Kaisha
    Inventors: Shoichiro Ikegami, Tomoo Akizuki, Hiroki Sasame, Yusuke Shimizu, Tatsuya Kinukawa
  • Patent number: 11275324
    Abstract: 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: Grant
    Filed: September 3, 2020
    Date of Patent: March 15, 2022
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hiroki Sasame, Tomoo Akizuki, Yusuke Shimizu
  • Publication number: 20210263454
    Abstract: 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: Application
    Filed: February 11, 2021
    Publication date: August 26, 2021
    Inventors: Shoichiro Ikegami, Tomoo Akizuki, Hiroki Sasame, Yusuke Shimizu, Tatsuya Kinukawa
  • Publication number: 20210072662
    Abstract: 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: Application
    Filed: September 3, 2020
    Publication date: March 11, 2021
    Inventors: Hiroki Sasame, Tomoo Akizuki, Yusuke Shimizu
  • Patent number: 10386755
    Abstract: 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: Grant
    Filed: June 27, 2018
    Date of Patent: August 20, 2019
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Shinsuke Kobayashi, Takaaki Akamatsu, Kenji Shindo, Kohei Okayasu, Hiroki Sasame
  • Patent number: 10216112
    Abstract: 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: Grant
    Filed: July 18, 2017
    Date of Patent: February 26, 2019
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hiroki Sasame, Kohei Okayasu, Shinsuke Kobayashi, Takaaki Akamatsu, Kenji Shindo, Takehiko Suzuki, Hironori Kato
  • Publication number: 20180307162
    Abstract: 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: Application
    Filed: June 27, 2018
    Publication date: October 25, 2018
    Inventors: Shinsuke Kobayashi, Takaaki Akamatsu, Kenji Shindo, Kohei Okayasu, Hiroki Sasame
  • Patent number: 10073383
    Abstract: 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: Grant
    Filed: October 5, 2016
    Date of Patent: September 11, 2018
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Shinsuke Kobayashi, Takaaki Akamatsu, Kenji Shindo, Kohei Okayasu, Hiroki Sasame
  • Patent number: 10031446
    Abstract: 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: Grant
    Filed: October 5, 2016
    Date of Patent: July 24, 2018
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Shinsuke Kobayashi, Takaaki Akamatsu, Kenji Shindo, Kohei Okayasu, Hiroki Sasame
  • Patent number: 10025236
    Abstract: 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: Grant
    Filed: June 12, 2017
    Date of Patent: July 17, 2018
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Hiroki Sasame, Shinsuke Kobayashi, Takaaki Akamatsu, Kohei Okayasu, Kenji Shindo
  • Patent number: 9946216
    Abstract: 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: Grant
    Filed: October 20, 2016
    Date of Patent: April 17, 2018
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Kohei Okayasu, Shinsuke Kobayashi, Takaaki Akamatsu, Kenji Shindo, Hiroki Sasame, Takuya Hayato
  • Publication number: 20180024458
    Abstract: 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: Application
    Filed: July 18, 2017
    Publication date: January 25, 2018
    Inventors: Hiroki Sasame, Kohei Okayasu, Shinsuke Kobayashi, Takaaki Akamatsu, Kenji Shindo, Takehiko Suzuki, Hironori Kato
  • Publication number: 20170363993
    Abstract: 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: Application
    Filed: June 12, 2017
    Publication date: December 21, 2017
    Inventors: Hiroki Sasame, Shinsuke Kobayashi, Takaaki Akamatsu, Kohei Okayasu, Kenji Shindo
  • Publication number: 20170115622
    Abstract: 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: Application
    Filed: October 20, 2016
    Publication date: April 27, 2017
    Inventors: Kohei Okayasu, Shinsuke Kobayashi, Takaaki Akamatsu, Kenji Shindo, Hiroki Sasame, Takuya Hayato
  • Publication number: 20170097590
    Abstract: 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: Application
    Filed: October 5, 2016
    Publication date: April 6, 2017
    Inventors: Shinsuke Kobayashi, Takaaki Akamatsu, Kenji Shindo, Kohei Okayasu, Hiroki Sasame