Of Residual Toner Patents (Class 399/129)
  • Patent number: 10095150
    Abstract: An image forming apparatus includes an image bearing member, a charging member, a charging voltage source, an electrostatic image forming portion, a developing device, a developing voltage source, a transfer portion, a transfer voltage source, and a controller. During image formation, the toner remaining on the image bearing member after transfer is collected into the developing device while forming an image. In a cleaning operation performed during non-image formation, while rotating the image bearing member, the controller transfers the toner from the charging member onto the image bearing member, passes the toner through the developing portion in an urged state, reverses a charge polarity of the toner to a normal polarity at a charging portion, and then transfers the toner reversed in charge polarity from the image bearing member onto the developing member at the developing portion to collect the toner in the developing device.
    Type: Grant
    Filed: September 10, 2015
    Date of Patent: October 9, 2018
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takashi Hiramatsu, Yusuke Usui, Kuniaki Tamagaki, Hiroyoshi Iwayama
  • 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
  • Patent number: 9551960
    Abstract: A CPU 26 sets the value of the applied voltage to a first set value when the absolute value of the amount of charge on the toner remaining on the intermediate transfer belt 8 is lower than a threshold value, and sets the value of the applied voltage to a second set value when the absolute value of the amount of charge on the toner remaining on the intermediate transfer belt 8 is equal to or greater than the threshold value, and when the first set value is VC1 and the second set value is VC2, the relationship |VC1|<|VC2| is established.
    Type: Grant
    Filed: August 24, 2015
    Date of Patent: January 24, 2017
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tetsuichiro Fujimoto, Toshiaki Miyashiro, Yasutaka Yagi
  • Patent number: 9042782
    Abstract: The light emitting portions 140 are mounted on the substrate 120, and emit neutralization light. The first end engagement portion 115 is engaged with the first end portion 121 of the substrate 120 opposite to the image carrier 2. The partitioning member 130 is connected to the housing 110, so as to form an opened portion that is opened to face the surface of the image carrier 2. The plurality of restriction protrusions 150 are arranged along an axial direction of the image carrier 2. The first end engagement portion 115 is disposed in the central portion of the plurality of restriction protrusions 150 in the arrangement direction. The arrangement direction of the plurality of restriction protrusions 150 curves, such that a central portion of the restriction protrusions in the axial direction is closer to the image carrier than end portions of the restriction protrusions in the axial direction.
    Type: Grant
    Filed: December 11, 2012
    Date of Patent: May 26, 2015
    Assignee: KYOCERA DOCUMENT SOLUTIONS INC.
    Inventors: Jun Nakai, Takeshi Watanabe, Katsuya Ota
  • Patent number: 8953962
    Abstract: An image forming apparatus may include a first and second mode. In the first mode, the image forming apparatus uses a second charging member to charge toner that remains on an intermediate transfer member and then transfers the charged, remaining toner to an image carrier in a primary transfer portion. In the second mode, the image forming apparatus transfers the remaining toner adhered to the second charging member in the first mode to the intermediate transfer member. Also in a second mode, the image forming apparatus controls so that a surface potential of the image carrier that reaches the primary transfer portion at a timing at which the remaining toner transferred to the intermediate transfer member passes through the primary transfer portion has a same polarity as that of a surface potential of the image carrier in the first mode and also has an absolute value smaller than that thereof.
    Type: Grant
    Filed: February 20, 2014
    Date of Patent: February 10, 2015
    Assignee: Canon Kabushiki Kaisha
    Inventors: Keisuke Ishizumi, Seiji Saito, Tomoo Akizuki, Takeshi Shinji
  • Patent number: 8892003
    Abstract: An image forming apparatus 100 includes: a common voltage-applying unit 8 that applies a voltage to charging-assistant members 7Y, 7M, and 7C of a plurality of image forming portions PY, PM, and PC; and a control unit 110, at the start of applying a voltage to the charging-assistant members of the plurality of image forming portions by the voltage-applying unit 8, switches the absolute value of the applied voltage from a smaller first value to a larger second value when images are formed by the plurality of image forming portions.
    Type: Grant
    Filed: October 25, 2012
    Date of Patent: November 18, 2014
    Assignee: Canon Kabushiki Kaisha
    Inventor: Michihiro Yoshida
  • Patent number: 8831480
    Abstract: An image forming apparatus includes: a drum; a charger; a developing portion; a transfer portion; a first adjuster; a second adjuster; and a controller for controlling the first and second adjuster. A first voltage is applied to the first adjuster during a period from a time when a rear end of a region in which an electrostatic image corresponding to a final image is to be formed passes through the first adjuster until a time when the rear end passes through the charger. The first voltage is lower in absolute value than a voltage applied to the first adjuster. A second voltage is applied to the second adjuster when a front end of a region of the drum opposing the first adjuster to which the first voltage is applied reaches the second adjuster. The second voltage is higher in absolute value than the voltage applied to the second adjuster.
    Type: Grant
    Filed: May 21, 2012
    Date of Patent: September 9, 2014
    Assignee: Canon Kabushiki Kaisha
    Inventors: Shota Soda, Jiro Kinokuni, Michihiro Yoshida
  • Patent number: 8737881
    Abstract: An image forming apparatus includes an image bearing member, a first toner charging member, provided downstream of a transfer device and upstream of a charging device with respect to a rotational direction of the image bearing member, for electronically charging toner remaining on the image bearing member, and a second toner charging member, provided downstream of the first toner charging member and upstream of the charging device with respect to the rotational direction, for electrically charging the toner remaining on the image bearing member by being supplied with a voltage of a polarity identical to a normal charge polarity of the toner. In addition, a controller controls application of a predetermined voltage to the first toner charging member, and a first AC voltage is applied to a developer.
    Type: Grant
    Filed: May 21, 2012
    Date of Patent: May 27, 2014
    Assignee: Canon Kabushiki Kaisha
    Inventors: Shota Soda, Jiro Kinokuni, Michihiro Yoshida
  • Publication number: 20140105626
    Abstract: A control unit is provided which controls at least one of a first power supply unit (a secondary transfer power supply connected to a secondary transfer roller) and a second power supply unit (high-voltage power supplies connected to a conductive brush and a conductive roller) so that a current supplied to a primary transfer region from a beginning of primary transfer until a beginning of secondary transfer has a magnitude larger than a magnitude of a current supplied to the primary transfer region from a beginning of image formation until the beginning of the primary transfer.
    Type: Application
    Filed: October 10, 2013
    Publication date: April 17, 2014
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Masaru Ohno, Shinji Katagiri, Yuji Kawaguchi
  • Patent number: 8693904
    Abstract: An image forming apparatus may include a first and second mode. In the first mode, the image forming apparatus uses a second charging member to charge toner that remains on an intermediate transfer member and then transfers the charged, remaining toner to an image carrier in a primary transfer portion. In the second mode, the image forming apparatus transfers the remaining toner adhered to the second charging member in the first mode to the intermediate transfer member. Also in a second mode, the image forming apparatus controls so that a surface potential of the image carrier that reaches the primary transfer portion at a timing at which the remaining toner transferred to the intermediate transfer member passes through the primary transfer portion has a same polarity as that of a surface potential of the image carrier in the first mode and also has an absolute value smaller than that thereof.
    Type: Grant
    Filed: October 25, 2011
    Date of Patent: April 8, 2014
    Assignee: Canon Kabushiki Kaisha
    Inventors: Keisuke Ishizumi, Seiji Saito, Tomoo Akizuki, Takeshi Shinji
  • Patent number: 8611793
    Abstract: Apparatus for electrically reconditioning a rotatable photoreceptor in an electrophotographic (EP) printer includes a charger, an exposure subsystem, a transfer station, and an erase lamp arranged in that order around the photoreceptor in the direction of rotation thereof. A first corona electrode is disposed within 3 cm of the surface of the photoreceptor, but not in contact therewith, between the transfer station and the erase lamp. The transfer station and the erase lamp are at most 1 cm apart. A second corona electrode is disposed within 3 cm of the surface of the photoreceptor, but not in contact therewith, after the erase lamp in the direction of rotation of the photoreceptor. The erase lamp and the second corona electrode are less than 1 cm apart.
    Type: Grant
    Filed: August 18, 2011
    Date of Patent: December 17, 2013
    Assignee: Eastman Kodak Company
    Inventors: Mark Cameron Zaretsky, David Steven Weiss
  • Patent number: 8606148
    Abstract: An electrophotographic photoreceptor is prepared for charging. Corona electrodes before and after the erase lamp apply respective biases to provide the correct sign of charge for cleaning, and to discharged trapped charges in the photoreceptor. Toner is then cleaned off the photoreceptor. This leaves the photoreceptor electrically and mechanically reconditioned and ready for its next printing cycle.
    Type: Grant
    Filed: August 18, 2011
    Date of Patent: December 10, 2013
    Assignee: Eastman Kodak Company
    Inventors: Mark Cameron Zaretsky, David Steven Weiss
  • Patent number: 8577248
    Abstract: When toner on an intermediate transfer member is picked up by a cleaning unit by transferring the toner to an image bearing member in a recovery operation, pickup conditions are controlled to be changed on the basis of the ambience detected in performing the recovery operation and such that the toner on the intermediate transfer member is picked up by the cleaning unit while being temporarily retained by a secondary transfer roller.
    Type: Grant
    Filed: March 2, 2011
    Date of Patent: November 5, 2013
    Assignee: Canon Kabushiki Kaisha
    Inventors: Shuhei Kawasaki, Motoki Adachi, Tomoo Akizuki
  • Patent number: 8532531
    Abstract: A charging member that charges residual toner on an intermediate transfer belt is a charging brush constituted by conductive fibers including an electric insulating portion and an electric conductive portion. Part of the outer circumferential surface of each conductive fiber is the conductive portion.
    Type: Grant
    Filed: December 14, 2010
    Date of Patent: September 10, 2013
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masaru Shimura, Masahiro Suzuki, Tsuguhiro Yoshida, Akihiko Uchiyama, Michio Uchida
  • Patent number: 8526855
    Abstract: An image forming apparatus includes: an image carrier; an exposure device; a developing device that develops the latent image on the image carrier by using a toner charged to a predetermined polarity and having an external additive; a transfer device that transfers a toner image developed on the image carrier to a transfer medium; a first charging member that charges the external additive and the transfer residual toner remaining on the image carrier and the image carrier after transfer to the same polarity as a polarity of the toner; a cleaning member that electrostatically attracts the external additive and the transfer residual toner charged by the first charging member; and a second charging member that charges the image carrier to an electric potential smaller in absolute value than an electric potential of the image carrier generated after the image carrier passes the cleaning member.
    Type: Grant
    Filed: July 6, 2009
    Date of Patent: September 3, 2013
    Assignee: Seiko Epson Corporation
    Inventors: Masaru Kobashi, Yoichi Yamada, Koji Migita, Takatomo Fukumoto
  • Publication number: 20130223880
    Abstract: A system for charging an insulating object on a static dissipative surface with a constant current includes a corona electrode in close proximity to the insulating surface; a shell electrode in close proximity to the corona electrode; a high voltage power supply connected to the corona electrode; wherein the potential of the shell electrode is raised to at least one tenth the magnitude of the potential of the corona electrode; sensing a first current from the high voltage power supply to the corona electrode; sensing a second current from the shell electrode to ground; and adjusting a voltage on the high voltage power supply to maintain a constant difference between the first current and the second current.
    Type: Application
    Filed: February 29, 2012
    Publication date: August 29, 2013
    Inventor: Mark C. Zaretsky
  • Publication number: 20130223881
    Abstract: A system for charging an insulating object on a static dissipative surface with a constant current includes a corona electrode in close proximity to the insulating surface; a shell electrode in close proximity to the corona electrode; a high voltage power supply connected to the corona electrode; wherein the potential of the shell electrode is raised to at least one tenth the magnitude of the potential of the corona electrode; sensing a first current from the high voltage power supply to the corona electrode; sensing a second current from the shell electrode to ground; and adjusting a voltage on the high voltage power supply to maintain a constant difference between the first current and the second current.
    Type: Application
    Filed: February 29, 2012
    Publication date: August 29, 2013
    Inventor: Mark C. Zaretsky
  • Publication number: 20130223883
    Abstract: A method for charging an insulating object on a static dissipative surface with a constant current includes placing a corona electrode in close proximity to the insulating object; placing a shell electrode in close proximity to the corona electrode; connecting a high voltage power supply to the corona electrode; placing a counter electrode on a side of the static dissipative surface opposite the corona electrode; maintaining the counter electrode at a constant potential; raising the potential of the shell electrode to at least one tenth the magnitude of the potential of the corona electrode; sensing a first current from the high voltage power supply to the corona electrode; sensing a second current from the shell electrode to ground; and adjusting a voltage on the high voltage power supply to maintain a constant difference between the first current and the second current.
    Type: Application
    Filed: February 29, 2012
    Publication date: August 29, 2013
    Inventor: Mark C. Zaretsky
  • Publication number: 20130223882
    Abstract: A method for charging a static dissipative object on an insulating surface with a constant current includes placing a corona electrode in close proximity to the static dissipative object; placing a shell electrode in close proximity to the corona electrode; connecting a high voltage power supply to the corona electrode; raising the potential of the shell electrode to at least one tenth the magnitude of the potential of the corona electrode; sensing a first current from the high voltage power supply to the corona electrode; sensing a second current from the shell electrode to ground; and adjusting a voltage on the high voltage power supply to maintain a constant difference between the first current and the second current.
    Type: Application
    Filed: February 29, 2012
    Publication date: August 29, 2013
    Inventor: Mark C. Zaretsky
  • Publication number: 20130114974
    Abstract: An image forming apparatus 100 includes: a common voltage-applying unit 8 that applies a voltage to charging-assistant members 7Y, 7M, and 7C of a plurality of image forming portions PY, PM, and PC; and a control unit 110, at the start of applying a voltage to the charging-assistant members of the plurality of image forming portions by the voltage-applying unit 8, switches the absolute value of the applied voltage from a smaller first value to a larger second value when images are formed by the plurality of image forming portions.
    Type: Application
    Filed: October 25, 2012
    Publication date: May 9, 2013
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Canon Kabushiki Kaisha
  • Patent number: 8346110
    Abstract: The image forming apparatus includes a photosensitive drum capable of bearing an electrostatic image, a development device having a developing sleeve capable of bearing a developer and a developer container capable of storing a magnetic toner, and a CPU controlling operation to discharge a developer having polarity opposite to a normally charged polarity to the photosensitive drum by enlarging a restoration electric field to force the developer having a normally charged polarity from the photosensitive drum to the development sleeve during image forming is not performed compared to that during normal image forming is performed, based on a weighted value (p×K) on an edge portion pixel number p of an edge portion of an output image.
    Type: Grant
    Filed: August 19, 2010
    Date of Patent: January 1, 2013
    Assignee: Canon Kabushiki Kaisha
    Inventor: Osamu Ariizumi
  • Patent number: 8315541
    Abstract: An image forming apparatus includes a rotatable photosensitive member; a charging device for electrically charging the photosensitive member; a developing device for developing with toner an electrostatic latent image formed on the photosensitive member electrically charged by the charging device; a transfer device for transferring a toner image from the photosensitive member onto an image-receiving member; and an auxiliary charging device for electrically charging untransferred toner on the photosensitive member to a normal charge polarity before the photosensitive member is electrically charged by the charging device; wherein effective widths WPM, WCD, WDD, WTD, and WACD of the photosensitive member, the charging device, the developing device, the transfer device, and the auxiliary charging device satisfy: WPM>WCD>WACD?WTD>WDD.
    Type: Grant
    Filed: November 17, 2009
    Date of Patent: November 20, 2012
    Assignee: Canon Kabushiki Kaisha
    Inventor: Jiro Kinokuni
  • Patent number: 8290385
    Abstract: A charge member charges secondary transfer remaining toner on an intermediate transfer member to a polarity opposite to a normal charge polarity. The remaining toner is moved by a transfer bias, from the intermediate transfer member onto an image bearing member. A BK station is arranged on the downstream of other stations. In a continuous BK monochromatic mode, by applying a reverse bias to transfer portions of the other stations and applying the transfer bias only to the BK station, remaining toner can be collected into the BK station (simultaneously with the transfer). In a full-color mode, remaining toner is collected into the station on the uppermost stream. Thus, the image bearing member for collecting remaining toner on the intermediate transfer member differs according to the mode, thereby suppressing the collection of remaining toner being concentrated on one image bearing member.
    Type: Grant
    Filed: January 13, 2012
    Date of Patent: October 16, 2012
    Assignee: Canon Kabushiki Kaisha
    Inventors: Ken Nakagawa, Kenji Kanari, Masaru Shimura, Takashi Shimada, Tomoo Akizuki, Masahiro Suzuki
  • Publication number: 20120257910
    Abstract: An image-forming apparatus for forming an image on a recording medium includes an image carrier for carrying a toner image corresponding to an image to be formed on the recording medium, a cleaning device including a cleaning member for cleaning the image carrier by removing residual toner remaining on an image-carrying face, and a bias-applying unit for applying a first bias for removing residual toner charged to a first polarity by electrostatic force from the image carrier such that the cleaning member captures residual toner, and expelling the residual toner charged to a second polarity, which is an opposite polarity to the first polarity, by electrostatic force from the cleaning member toward the image carrier, between the image carrier and the cleaning member.
    Type: Application
    Filed: March 29, 2012
    Publication date: October 11, 2012
    Inventor: Takeshi WATANABE
  • Publication number: 20120224880
    Abstract: An image forming apparatus includes a latent-image carrier that is rotatable and carries a latent image on an outer peripheral surface thereof; a transfer unit that transfers a developer image obtained by developing the latent image with developer onto a transfer medium; a cleaning unit that is disposed downstream of the transfer unit in a rotational direction of the latent-image carrier and removes the developer from the latent-image carrier after the developer image is transferred; a light source that is disposed between the transfer unit and the cleaning unit and emits light for removing electric charge from the latent-image carrier; and a guiding member that is disposed below the cleaning unit and above a transport path of the transfer medium, receives the developer that falls from the cleaning unit at an upper surface thereof, and guides the light to the latent-image carrier.
    Type: Application
    Filed: July 27, 2011
    Publication date: September 6, 2012
    Applicant: FUJI XEROX CO., LTD.
    Inventors: Naoki SATO, Kuniaki TANAKA
  • Patent number: 8238782
    Abstract: Provided is an image forming apparatus having a charge brush for charging a transfer residual toner remaining on an intermediate transfer member. A toner is adhered to the charge brush. While a charge voltage is applied to the charge brush, the toner adhered to the charge brush is attracted by an electric field onto the charge brush. However, when the charge voltage is not applied to the charge brush, the toner adhered to the charge brush is moved to the intermediate transfer member. When a subsequent toner image is formed on the toner adhered to the intermediate transfer member, the quality of the subsequent image is deteriorated. Accordingly, the charge voltage is applied to the charge brush when an intermediate transfer area to which the toner image is transferred onto the intermediate transfer member immediately afterward faces the charge brush.
    Type: Grant
    Filed: August 18, 2011
    Date of Patent: August 7, 2012
    Assignee: Canon Kabushiki Kaisha
    Inventor: Takamitsu Soda
  • Patent number: 8180247
    Abstract: There is a charge member which charges secondary transfer remaining toner on an intermediate transfer member to a polarity opposite to a normal charge polarity. The transfer remaining toner charged by the charge member is moved in the direction opposite to that of normal toner by a transfer bias and moved from the intermediate transfer member onto an image bearing member. A BK station is arranged on the downstream of other stations. In a continuous BK monochromatic mode, by applying a reverse bias to transfer portions of the other stations and applying the transfer bias only to the BK station, waste toner can be collected into the BK station (simultaneously with the transfer). In a full-color mode, since each transfer bias is applied to all stations, the waste toner is collected into the station on the uppermost stream.
    Type: Grant
    Filed: June 15, 2011
    Date of Patent: May 15, 2012
    Assignee: Canon Kabushiki Kaisha
    Inventors: Ken Nakagawa, Kenji Kanari, Masaru Shimura, Takashi Shimada, Tomoo Akizuki, Masahiro Suzuki
  • Publication number: 20120106998
    Abstract: An image forming apparatus may include a first and second mode. In the first mode, the image forming apparatus uses a second charging member to charge toner that remains on an intermediate transfer member and then transfers the charged, remaining toner to an image carrier in a primary transfer portion. In the second mode, the image forming apparatus transfers the remaining toner adhered to the second charging member in the first mode to the intermediate transfer member. Also in a second mode, the image forming apparatus controls so that a surface potential of the image carrier that reaches the primary transfer portion at a timing at which the remaining toner transferred to the intermediate transfer member passes through the primary transfer portion has a same polarity as that of a surface potential of the image carrier in the first mode and also has an absolute value smaller than that thereof.
    Type: Application
    Filed: October 25, 2011
    Publication date: May 3, 2012
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Keisuke Ishizumi, Seiji Saito, Tomoo Akizuki, Takeshi Shinji
  • Patent number: 8131178
    Abstract: A cleaning station is usable with an image forming apparatus that has at least one developer configured to deliver toner of a first polarity to a latent image formed on a photoconductor. The cleaning station includes a transfer mechanism configured to transfer the toner of the first polarity from the latent image to a print medium, a charging station configured to charge waste toner not transferred from the transfer mechanism to the print medium to a second polarity opposite the first polarity, and a cleaner assembly configured to collect the waste toner from the transfer mechanism.
    Type: Grant
    Filed: May 14, 2009
    Date of Patent: March 6, 2012
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Richard L. Swantner, Sarah Elizabeth Swantner
  • Publication number: 20120051785
    Abstract: The present invention ensures stable cleaning performance with respect to remaining toner on an intermediate transfer belt without increasing the size and cost of an image forming apparatus. The present invention provides an image forming apparatus in which residual toner charged by a toner charging member is transferred from the intermediate transfer belt to a photosensitive drum, the toner charging member is placed with respect to the intermediate transfer belt in a rotation direction of the intermediate transfer belt such that a first distance of the intermediate transfer belt from a position where a secondary transfer member contacts the intermediate transfer belt to a position where the toner charging member contacts the intermediate transfer belt is longer than a second distance from the position where the toner charging member contacts the intermediate transfer belt to a position where an image bearing member placed most upstream contacts the intermediate transfer belt.
    Type: Application
    Filed: August 15, 2011
    Publication date: March 1, 2012
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Tomoaki Nakai, Kimitaka Ichinose, Hiroyuki Kadowaki, Takao Kume
  • Publication number: 20110268469
    Abstract: The image forming apparatus includes a charge member that charges residual toner and is a conductive roller having electrical conductivity and rotates in according to rotation of the intermediate transfer member, and the conductive roller includes a foamed front layer and charges the residual toner upstream and downstream of a contact area in which the conductive roller contacts the intermediate transfer member and charges the residual toner in a void formed on the foamed layer in the contact area. This enables the residual toner on the intermediate transfer member to be sufficiently charged without damaging the intermediate transfer member.
    Type: Application
    Filed: April 18, 2011
    Publication date: November 3, 2011
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Keisuke Ishizumi, Seiji Saito, Tomoo Akizuki, Takeshi Shinji
  • Patent number: 8036573
    Abstract: An image forming apparatus includes an image carrying member, an image writing unit, a development unit, a transfer device, a charging device, and a toner charge control device. The image writing unit forms a latent image on the image carrying member, which is developed as a toner image by the development unit, and the toner image is transferred to a transfer member by the transfer device. The charging device charges the image carrying member and toner on the image carrying member. The toner charge control device, controls a polarity of charge and charging voltage level of toner remaining on the image carrying member. The toner charge control device includes an endless belt having a surface made of a conductive material, a support member extending the endless belt pressed against the image carrying member, and a bias voltage applicator for supplying a voltage to the surface of the endless belt.
    Type: Grant
    Filed: August 6, 2008
    Date of Patent: October 11, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Hidekazu Shono, Naoki Nakatake, Tetsumaru Fujita
  • Patent number: 8027612
    Abstract: Provided is an image forming apparatus having a charge brush for charging a transfer residual toner remaining on an intermediate transfer member. A toner is adhered to the charge brush. While a charge voltage is applied to the charge brush, the toner adhered to the charge brush is attracted by an electric field onto the charge brush. However, when the charge voltage is not applied to the charge brush, the toner adhered to the charge brush is moved to the intermediate transfer member. When a subsequent toner image is formed on the toner adhered to the intermediate transfer member, the quality of the subsequent image is deteriorated. Accordingly, the charge voltage is applied to the charge brush when an intermediate transfer area to which the toner image is transferred onto the intermediate transfer member immediately afterward faces the charge brush.
    Type: Grant
    Filed: April 2, 2008
    Date of Patent: September 27, 2011
    Assignee: Canon Kabushiki Kaisha
    Inventor: Takamitsu Soda
  • Patent number: 8027617
    Abstract: In the case where image formation is performed by using a part of a plurality of image forming units, an associated image bearing member of a remaining part of the plurality of image forming units is rotated together with an intermediary transfer member or a recording material carrying member while a voltage of a polarity opposite to that of polishing particles is applied to an electric charge imparting member.
    Type: Grant
    Filed: November 26, 2007
    Date of Patent: September 27, 2011
    Assignee: Canon Kabushiki Kaisha
    Inventor: Yusuke Ishida
  • Patent number: 8019249
    Abstract: A charging device includes a first charging member held in contact with an image carrier, a toner image formed thereon, a bias showing a polarity same as that of the charged potential of toner applied thereto, a second charging member arranged downstream relative to the first charging member as viewed in the moving direction of the image carrier and held in contact with the image carrier, a bias showing a polarity opposite to the charged potential of toner applied thereto, a collection member held in contact with the second charging member to collect the toner adhering to the second charging member, a bias being applied thereto and a collection member bias control unit for controlling the bias applied to the collection member according to image forming conditions information.
    Type: Grant
    Filed: November 6, 2008
    Date of Patent: September 13, 2011
    Assignee: Seiko Epson Corporation
    Inventor: Masaru Kobashi
  • Publication number: 20110217060
    Abstract: When toner on an intermediate transfer member is picked up by a cleaning unit by transferring the toner to an image bearing member in a recovery operation, pickup conditions are controlled to be changed on the basis of the ambience detected in performing the recovery operation and such that the toner on the intermediate transfer member is picked up by the cleaning unit while being temporarily retained by a secondary transfer roller.
    Type: Application
    Filed: March 2, 2011
    Publication date: September 8, 2011
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Shuhei Kawasaki, Motoki Adachi, Tomoo Akizuki
  • Publication number: 20110188881
    Abstract: The image forming apparatus is capable of collecting discharged toner satisfactorily even when a power source for discharging toner from a voltage application member to a moving member and a power source for collecting the discharged toner from the moving member onto an image bearing member are provided in common.
    Type: Application
    Filed: January 21, 2011
    Publication date: August 4, 2011
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Tomoo Akizuki, Keisuke Ishizumi, Seiji Saito
  • Patent number: 7978998
    Abstract: There is a charge member which charges secondary transfer remaining toner on an intermediate transfer member to a polarity opposite to a normal charge polarity. The transfer remaining toner charged by the charge member is moved in the direction opposite to that of normal toner by a transfer bias and moved from the intermediate transfer member onto an image bearing member. A BK station is arranged on the downstream of other stations. In a continuous BK monochromatic mode, by applying a reverse bias to transfer portions of the other stations and applying the transfer bias only to the BK station, waste toner can be collected into the BK station (simultaneously with the transfer). In a full-color mode, since each transfer bias is applied to all stations, the waste toner is collected into the station on the uppermost stream.
    Type: Grant
    Filed: February 1, 2008
    Date of Patent: July 12, 2011
    Assignee: Canon Kabushiki Kaisha
    Inventors: Ken Nakagawa, Kenji Kanari, Masaru Shimura, Takashi Shimada, Tomoo Akizuki, Masahiro Suzuki
  • Publication number: 20110150524
    Abstract: An image forming apparatus includes a drum for bearing a toner image; a rotatable belt onto which the toner image is to be transferred from the drum; a primary transfer member for primary transferring the toner image from the drum onto the belt; a secondary transfer member for secondary transferring the toner image from the belt onto a transfer material; and a charging member for electrically charging toner remaining on the belt. The image forming apparatus is capable of executing a belt cleaning mode in which the toner remaining on the belt is electrically charged, and a charging member cleaning mode in which the toner is transferred from the charging member onto the belt and then onto the drum. When the charging member cleaning mode is executed, the charging member is moved at least once from a belt separation position or away from a belt contact position.
    Type: Application
    Filed: December 14, 2010
    Publication date: June 23, 2011
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Keisuke Ishizumi, Tomoo Akizuki, Takeshi Shinji, Seiji Saito
  • Publication number: 20110116834
    Abstract: An image forming apparatus includes a photosensitive member; a charging device for electrically charging the photosensitive member; an exposure device for exposing to light the photosensitive member charged by the charging device to form an electrostatic image on the photosensitive member; a developing device for developing the electrostatic image on the photosensitive member with toner to form a toner image; a transfer portion for transferring the toner image from the photosensitive member onto an image receiving member; a toner charging portion, disposed upstream of the charging device and downstream of the transfer portion with respect to a rotational direction of the photosensitive member, for electrically charging the toner remaining on the photosensitive member without being transferred onto the image receiving member; and control portion for controlling the charging device and the exposure device so that a stripe-shaped electrostatic image is repeatedly formed in substantially parallel to a longitudina
    Type: Application
    Filed: November 15, 2010
    Publication date: May 19, 2011
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Jiro Kinokuni, Michihiro Yoshida
  • Patent number: 7945190
    Abstract: A cleanerless image forming apparatus removes and collects transfer residual toner for reuse by performing cleaning simultaneously with developing. The image forming apparatus includes first and second toner charging members configured to apply an electrical charge having the same polarity as a toner normal charging polarity to the transfer residual toner, and a discharging member that is configured to discharge a drum and is disposed between the first and second toner charging members.
    Type: Grant
    Filed: December 18, 2007
    Date of Patent: May 17, 2011
    Assignee: Canon Kabushiki Kaisha
    Inventor: Norihiko Kubo
  • Patent number: 7945191
    Abstract: An image forming apparatus includes: an image holder; a charging unit that charges the image holder; a latent image forming unit; a developing unit that forms a toner image; a transfer unit that transfers the toner image formed on the surface of the image holder onto a recording medium; a toner-particle removal unit that removes toner particles remaining on the surface of the image holder after the transfer of the toner image by the transfer unit; and an external-additive removal unit that includes a conductive blade disposed to contact the surface of the image holder and removes, after the transfer of the toner image by the transfer unit, external additive remaining on the surface of the image holder using the conductive blade while applying a voltage to the surface of the image holder via the conductive blade.
    Type: Grant
    Filed: August 27, 2009
    Date of Patent: May 17, 2011
    Assignee: Fuji Xerox Co., Ltd.
    Inventor: Masaharu Shirai
  • Patent number: 7941075
    Abstract: An image forming apparatus includes an image carrier, a charging unit including a charge member that is disposed facing the image carrier across a gap therebetween and charges the image carrier by using electrical discharge caused by applying thereto a voltage including an alternating current component superimposed on a direct current component, a latent image forming unit, a developing unit to supply toner for developing the latent image formed on the image carrier into a toner image and to collect residual toner remaining on the image carrier, a transfer unit, and a toner spreading member to spread toner on the image carrier and disposed upstream from the charging unit in a direction of movement of the image carrier and downstream from the transfer unit in the direction of movement of the image carrier.
    Type: Grant
    Filed: June 10, 2009
    Date of Patent: May 10, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Emiko Shiraishi, Shigekazu Enoki, Jun Yura, Hirokatsu Suzuki
  • Patent number: 7907871
    Abstract: An image forming apparatus that is more capable of preventing the occurrence of image quality deterioration caused by defective charging of a photoreceptor than the conventional one. As a charging device, there is used a member which has: a conductive sheet that causes the surface thereof applied with a predetermined bias to abut against the surface of the photoreceptor after passing through a primary transfer nip obtained by abutment between the photoreceptor and an intermediate transfer belt and before entering a development step performed by a developing device; a conductive brush member that applies a predetermined bias to the surface of the photoreceptor obtained after passing through the position of abutment with the sheet and before entering the development step; and a charging roller that uniformly charges the surface of the photoreceptor after passing through the position of abutment with the brush and before entering the development step.
    Type: Grant
    Filed: December 12, 2007
    Date of Patent: March 15, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Yoshio Sakagawa, Tetsumaru Fujita, Yuji Nagatomo
  • Patent number: 7903998
    Abstract: An image forming apparatus having at least a latent electrostatic image bearing member, and a recharging unit configured to recharge a residual toner remaining on the latent electrostatic image bearing member, wherein after transfer, the residual toner is passed through the recharging unit and is then recovered in a developing device; a charging component of the recharging unit that comes into contact with the latent electrostatic image bearing member is a polymer sheet having a surface roughness (Ra) of 0.12 ?m to 0.51 ?m; the toner contains at least a pigment, a binder resin, and a releasing agent, and contains inorganic fine particles as an external additive, and the amount of the inorganic fine particles and the amount of the releasing agent satisfy three specific Expressions.
    Type: Grant
    Filed: March 12, 2008
    Date of Patent: March 8, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Mitsuyo Matsumoto, Chiyoshi Nozaki, Takuya Kadota, Katsunori Kurose, Tsuyoshi Nozaki, Atsushi Yamamoto, Yoshimichi Ishikawa
  • Patent number: 7903999
    Abstract: An image forming apparatus includes a photosensitive member; a developing device for developing an electrostatic image formed on said photosensitive member into a toner image; a transfer charger for transferring a toner image from said photosensitive member onto an image receiving member; a non-rotational brush and a rotatable brush for electrically charging toner, which remains on said photosensitive member after image transfer by said transfer charger, to collect the remaining toner into said developing device; a driving mechanism provided with a driving source for rotating said rotatable brush; and a moving mechanism for reciprocating said non-rotational brush by a driving force through said rotatable brush in a direction along an axis of said photosensitive member.
    Type: Grant
    Filed: October 8, 2009
    Date of Patent: March 8, 2011
    Assignee: Canon Kabushiki Kaisha
    Inventors: Jiro Kinokuni, Kazufumi Muto
  • Publication number: 20110013937
    Abstract: An image forming apparatus is constituted by a rotatable image bearing member; a charging member for electrically charging the image bearing member in contact with the image bearing member; developing member, containing polishing particles, for collecting toner from the image bearing member and effecting development on the basis of an electrostatic latent image formed on the image bearing member; a transfer member for transferring a toner image formed on the image bearing member onto a transfer material; an auxiliary charging member, located downstream from a transfer portion and upstream from the charging member with respect to a movement direction of the image bearing member, for electrically charging toner remaining on the image bearing member after the transfer by contact with the image bearing member; and control means for performing a discharging mode, for discharging polishing particles from the auxiliary charging member onto the image bearing member on the basis of an image ratio of an image to be for
    Type: Application
    Filed: September 22, 2010
    Publication date: January 20, 2011
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Yusuke ISHIDA
  • Patent number: 7873298
    Abstract: A cleaning device including a polarity control unit to control a charge polarity of residual toner particles, a cleaning member, a surface of which is movable, to electrostatically remove the residual toner particles, provided on a downstream side from the polarity control unit relative to a surface moving direction of an image bearing member, a toner collecting unit to collect the residual toner particles on the cleaning member, and a neutralizing member to neutralize the image bearing member, provided on a downstream side from the polarity control unit and an upstream side from the cleaning member relative to the surface moving direction of the image bearing member.
    Type: Grant
    Filed: January 10, 2008
    Date of Patent: January 18, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Yasuyuki Yamashita, Hidetoshi Yano, Oasamu Naruse, Naomi Sugimoto, Kenji Sugiura
  • Publication number: 20100329714
    Abstract: An image forming apparatus including: a photoreceptor; a charging section to charge the photoreceptor; a developing section to develop a latent image; a transfer section to transfer the developed image to a transfer sheet using a contact transfer method; a cleaning section to remove a remaining toner on the photoreceptor; a control section that performs control so that a toner image is formed in an image forming region, the toner image is transferred to the transfer sheet, and a toner image is formed which is not transferred to the transfer sheet in a region between image forming regions on the photoreceptor; and a charge elimination section provided between the transfer section and the cleaning section; wherein the control section controls polarities of electric current applied to the transfer section and the charge elimination section so that the polarities differ between the image forming region and the region between images.
    Type: Application
    Filed: June 21, 2010
    Publication date: December 30, 2010
    Applicant: KONICA MINOLTA BUSINESS TECHNOLOGIES, INC.
    Inventors: Shinichi Tsukamura, Keiki Katsumata
  • Patent number: 7805089
    Abstract: An image forming apparatus performs a control sequence in which an AC voltage having a peak-to-peak voltage is applied to a charging member so that a relationship between an absolute value of a surface potential of an image bearing member at a portion under a transfer residual toner remaining on the image bearing member which has been electrically charged by the charging member during non-image formation and an absolute value of a surface potential of a developer carrying member is reversed with respect to a relationship between these absolute values during image formation.
    Type: Grant
    Filed: December 15, 2009
    Date of Patent: September 28, 2010
    Assignee: Canon Kabushiki Kaisha
    Inventor: Tadanobu Yoshikawa