Simultaneously Patents (Class 399/150)
  • Patent number: 10684573
    Abstract: An image forming method includes: placing developer on a medium in accordance with image data to form a developer image; and fixing the developer image to the medium while conveying the medium along a conveying direction. The image forming method further includes: determining, as a blocked region, a region of the developer image where no developer is placed and whose upstream side in the conveying direction is blocked by a developer region where the developer is placed; and forming at least one groove extending in the conveying direction in an upstream region of the developer image that is located upstream of the blocked region in the conveying direction and included in the developer region.
    Type: Grant
    Filed: June 20, 2019
    Date of Patent: June 16, 2020
    Assignee: Oki Data Corporation
    Inventors: Teruaki Kuroda, Masahiro Kawano, Yoshiaki Kusakabe
  • Patent number: 10248043
    Abstract: In a case where a collection mode in which an exposure unit forms a first potential on a photosensitive member and a developing unit collects discharging toner discharged from the developing unit to a position where the first potential is formed is executed, a potential forming unit forms, on an intermediate transfer member, a potential same as a normal charging polarity of toner and an absolute value greater than an absolute value of the first potential, and a charging power supply applies, to a charging member, a voltage having a polarity same as the normal charging polarity and an absolute value greater than an absolute value of the first potential.
    Type: Grant
    Filed: November 17, 2017
    Date of Patent: April 2, 2019
    Assignee: Canon Kabushiki Kaisha
    Inventors: Shuichi Tetsuno, Shinji Katagiri, Takayuki Tanaka, Tsuguhiro Yoshida, Takahiro Ikeda
  • Patent number: 9592536
    Abstract: There is herein described an improved contact cleaning surface and an improved method for cleaning surfaces. More particularly, there is described a contact cleaning surface comprising a micro-structured surface adapted to collect and/or remove microscopically sized contaminating material from a contaminated surface.
    Type: Grant
    Filed: September 24, 2009
    Date of Patent: March 14, 2017
    Assignee: ITW LIMITED
    Inventor: Sheila Hamilton
  • Patent number: 9400455
    Abstract: An imaging device includes a moving surface for transferring a developed toner image during an image transfer operation, a sensing unit for detecting the amount of residual toner remaining on the moving surface after the image transfer operation, and a cleaning unit for selectively cleaning the residual toner from the moving surface. A controller coupled to the sensing unit and the cleaning unit selectively adjusts an operating characteristic of the cleaning unit based on the amount of residual toner detected by the sensing unit.
    Type: Grant
    Filed: July 2, 2013
    Date of Patent: July 26, 2016
    Assignee: Lexmark International, Inc.
    Inventors: Roger S Cannon, Kerry L Embry, Heidi L Hays, William Claiborne Ryle, Julie Ann Gordon Whitney
  • Patent number: 9360805
    Abstract: An intermediate transfer unit includes an intermediate transfer belt, a plurality of rollers, a cleaning unit, a brush unit, and a pressing member. The brush unit is located at the outer circumferential surface part of the intermediate transfer belt in contact with the roller. The brush unit is located at upstream of a contacting part with the cleaning unit in a running direction of the intermediate transfer belt. The brush unit is configured to impart electric charge to the remnant toner by a contact friction with the outer circumferential surface of the intermediate transfer belt. The pressing member is configured to press the brush unit along a direction of contact/separation with respect to the outer circumferential surface of the intermediate transfer belt.
    Type: Grant
    Filed: March 23, 2014
    Date of Patent: June 7, 2016
    Assignee: Kyocera Document Solutions Inc.
    Inventor: Satoru Yonemoto
  • Patent number: 9330916
    Abstract: A silicon carbide substrate having a first main surface and a second main surface opposite to the first main surface is prepared. A surface electrode is formed in contact with the first main surface of the silicon carbide substrate. An adhesive tape is adhered to the surface electrode so as to cover the surface electrode. The silicon carbide substrate is heated at a first pressure lower than atmospheric pressure, with the adhesive tape being adhered to the surface electrode. After the silicon carbide substrate is heated, the second main surface of the silicon carbide substrate is ground. After the second main surface is ground, the second main surface of the silicon carbide substrate is processed at a second pressure lower than atmospheric pressure, with the adhesive tape being adhered to the surface electrode.
    Type: Grant
    Filed: April 29, 2015
    Date of Patent: May 3, 2016
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventor: Hiroyuki Kitabayashi
  • Patent number: 8809752
    Abstract: A boosting circuit includes a switch element, a first coil, a second coil, and a capacitor. The switch element generates a first alternating current voltage having a first frequency from a direct current voltage. The first coil generates a magnetic field around the first coil with a flow of the first alternating current voltage having the first frequency in the first coil. The first coil also induces an eddy current in the object with the magnetic field to inductively heat the object. The second coil is cumulatively connected to the first coil. The capacitor is connected to the first coil and the second coil in a parallel manner.
    Type: Grant
    Filed: March 20, 2007
    Date of Patent: August 19, 2014
    Assignee: Ricoh Company, Ltd.
    Inventor: Tomofumi Yamashita
  • Patent number: 8693919
    Abstract: An image forming apparatus comprising: a photosensitive drum having a circumferential surface, on which a developer image is formed; a transfer member configured to transfer the developer image from the circumferential surface of the photosensitive drum to a recording medium conveyed along the conveying path in a conveying direction; a collecting member; and a motor capable of performing a forward rotation and a reverse rotation; wherein, based on a timing when a portion of the circumferential surface of the photosensitive drum faces an upstream side edge of the developer image on the recording medium in the conveying direction, a time elapsed until the motor is stopped to change from performing the forward rotation to the reverse rotation is longer than a time elapsed until the portion of the circumferential surface of the photosensitive drum that faced the upstream side edge of the developer image faces the collecting member.
    Type: Grant
    Filed: March 24, 2011
    Date of Patent: April 8, 2014
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventor: Masatoshi Shiraki
  • Patent number: 8532545
    Abstract: A developing device in an image forming apparatus includes: a first developer carrier that rotates in a same direction as a rotating direction of an image carrier of the image forming apparatus so as to supply developer to the image carrier; and a second developer carrier that rotates in a direction opposite to the rotating direction of the image carrier so as to supply the developer to the image carrier. The developing device simultaneously performs a refreshing operation of performing replacement of the developer and a filming removal operation of causing the image carrier to rotate idle while forming an image for use in the refreshing operation and causing the first and second developer carriers to rotate in their respective rotating directions.
    Type: Grant
    Filed: November 10, 2010
    Date of Patent: September 10, 2013
    Assignee: Ricoh Company, Limited
    Inventors: Tomonari Hokkyoh, Takashi Suzuki, Koutarou Yamada, Katsuhiro Akinaga
  • Patent number: 8406664
    Abstract: An image forming apparatus includes a plurality of image carriers, a latent image forming unit, and a plurality of developing units. Each of the developing unit forms an image to have a color difference of equal to or less than about five with respect to an initial unicolor image formed by using a toner not containing a reversely-transferred toner of another color when a toner contained in a toner container is consumed by about 70%.
    Type: Grant
    Filed: September 4, 2008
    Date of Patent: March 26, 2013
    Assignee: Ricoh Company, Ltd.
    Inventors: Tetsumaru Fujita, Yuji Nagatomo
  • Patent number: 8264720
    Abstract: A printing control apparatus to store print data in a storage area from a print application and to send the print data to a print apparatus. The printing control apparatus includes a control unit to send, when a billing code is set in a first received print data, the print data to the print apparatus and to control, when no billing code is set in the first received print data, an order of the print data so that subsequent data is sent before (or instead of) the first received print data, a display control unit to display a list of the print data received from the print application, and a setting unit to select one or more print data from the list of the print data displayed by the display control unit to set a billing code according to input by a user. Related methods are also disclosed.
    Type: Grant
    Filed: March 6, 2008
    Date of Patent: September 11, 2012
    Assignee: Canon Kabushiki Kaisha
    Inventor: Hideki Sugiyama
  • Publication number: 20120213542
    Abstract: A developing roller which comes into contact with a latent image carrier drum on a first side with respect to an imaginary vertical plane passing through the rotation center of the latent image carrier drum, thereby developing a latent image which is carried on the latent image carrier drum by a liquid developer that includes toner and carrier liquid is provided, and a squeeze roller which comes into contact with the latent image carrier drum developed by the developing roller on a second side on the opposite side to the first side with respect to the imaginary vertical plane further on the upper side in the vertical direction than an imaginary horizontal plane passing through the rotation center of the latent image carrier drum and perpendicular to the imaginary vertical plane, thereby squeezing an image developed to the latent image carrier drum is provided.
    Type: Application
    Filed: February 15, 2012
    Publication date: August 23, 2012
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Yuichiro TSUKADA, Tsutomu SASAKI, Kazuhiro NISHIYAMA, Kazuma MIYAZAWA, Naoyuki OKUMURA
  • Patent number: 7995960
    Abstract: An image forming apparatus includes photosensitive members which are aligned along a conveying direction of a transfer medium and on each of which an electrostatic latent image is to be formed; developing units which supply a plurality of colors of developing agent to the photosensitive members, respectively; and cleaning rollers which slidably contact the photosensitive members to collect at least one of paper powder and developing agent adhering to surfaces of the photosensitive members, respectively. A most upstream cleaning roller which slidably contacts a most upstream photosensitive member in the conveying direction is provided with a paper powder absorption shaft which attracts and absorbs paper powder from the cleaning roller. A most downstream cleaning roller which slidably contacts a most downstream photosensitive member in the conveying direction is not provided with the paper powder absorption shaft.
    Type: Grant
    Filed: December 22, 2008
    Date of Patent: August 9, 2011
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventor: Naoya Kamimura
  • Patent number: 7751752
    Abstract: An image forming apparatus includes a rotatable brush in contact with an image bearing member at a position downstream of transfer means and upstream of charging means in a rotational direction of the image bearing member. The rotational brush is configured to supply electrical charge to residual toner that remains on the image bearing member. The image forming apparatus executes a mode for removing toner particles attached to the brush by setting a peripheral speed of the brush to be lower than that of the image bearing member during an image forming time period and setting the peripheral speed of the brush to be higher than that of the image bearing member during at least part of a non-image forming time period.
    Type: Grant
    Filed: November 6, 2007
    Date of Patent: July 6, 2010
    Assignee: Canon Kabushiki Kaisha
    Inventor: Isao Komatsu
  • Patent number: 7627269
    Abstract: An image forming apparatus includes an image bearing member; a charging member for contacting a peripheral surface of the image bearing member to electrically charge the peripheral surface; a first developing device for forming a first developed image on the peripheral surface of the image bearing member charged by the charging member; a second developing device for forming a second developed image on the peripheral surface, wherein a combined developed image is formed by superimposing the first developed image and the second developed image on a common transfer material, wherein when the combined image is being formed, the charging member is cleaned by transferring, by an electric field, material deposited on the charging member to a region between the first developed image and the second developed image on the peripheral surface of the image bearing member, and wherein the first developed image and the second developed image are not formed in the region.
    Type: Grant
    Filed: April 3, 2006
    Date of Patent: December 1, 2009
    Assignee: Canon Kabushiki Kaisha
    Inventors: Minoru Matsuguma, Kenji Matsuda, Masaki Ojima, Katsuhiro Kojima, Hideki Matsumoto
  • Patent number: 7603058
    Abstract: An image formation apparatus which includes a rotating image-bearing body, a charging section, an exposure section, a developing section, a transfer section, and a residue toner-charging section. The charging section charges the image-bearing body. The exposure section forms an electrostatic latent image on the image-bearing body that has been charged. The developing section develops the electrostatic latent image and forms a toner image. The transfer section transfers the toner image to a transfer body. The residue toner-charging section is provided upstream of the charging section and downstream of the transfer section and, after the transfer, charges transfer residue toner to a normal polarity. The transfer residue toner that has been charged to the normal polarity by the residue toner-charging section is recycled at the developing section. The residue toner-charging section is provided with a nonwoven fabric, which features conductivity and touches against the image-bearing body.
    Type: Grant
    Filed: March 15, 2006
    Date of Patent: October 13, 2009
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Jin Iwasaki, Koya Tanaka
  • Patent number: 7593669
    Abstract: An image forming apparatus includes an exposure device for exposing an electrically charged surface of an image bearing member to light to form an electrostatic image; a developing device capable of collecting a transfer residual developer remaining on the image bearing member; a transferring device for transferring a developer image from the image bearing member onto a transfer medium at a transfer position; and a controller for executing, during non-image formation, a developer collecting mode in which a developer of an opposite polarity is collected into the developing device by driving the image bearing member and by causing the developer carrying member to stop its rotation or rotate at a speed slower than a rotational speed thereof during image formation while generating a potential difference capable of transferring the developer of the opposite polarity from the image bearing member onto the developer carrying member.
    Type: Grant
    Filed: September 13, 2007
    Date of Patent: September 22, 2009
    Assignee: Canon Kabushiki Kaisha
    Inventor: Koji Shigehiro
  • Patent number: 7469116
    Abstract: An image forming apparatus includes a rotatable image bearing member; a charging member for electrically charging the image bearing member; developing device means for developing an electrostatic latent image formed on said image bearing member into a toner image and for collecting toner from the image bearing member; transfer device means for transferring the toner image onto a transfer material; a brush member rotatable in a direction identical or opposite to a rotational direction of the image bearing member and disposed downstream from the transfer device means and upstream from the charging member in the rotational direction of the image bearing member, the brush member contacting transfer residual toner while being supplied with a DC voltage of an opposite polarity to a normal charge polarity of the toner; and a moving member for moving the toner in a rotational axis direction of the brush member while contacting the brush member.
    Type: Grant
    Filed: November 27, 2006
    Date of Patent: December 23, 2008
    Assignee: Canon Kabushiki Kaisha
    Inventor: Kenichiro Kitajima
  • Patent number: 7428395
    Abstract: In an image forming apparatus using simultaneous developing and cleaning type developing units, this invention installs brush members to disturb toners remaining on photosensitive drums movably in the direction to contact with photosensitive drums corresponding to the displacement of the surfaces of the photosensitive drums by empty weights and keep the ends of the brush members always in contact with the photosensitive drums.
    Type: Grant
    Filed: March 21, 2005
    Date of Patent: September 23, 2008
    Assignees: Kabushiki Kaisha Toshiba, Toshiba Tec Kabushiki Kaisha
    Inventors: Masashi Takahashi, Minoru Yoshida, Takeshi Watanabe
  • Publication number: 20080152387
    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: Application
    Filed: December 18, 2007
    Publication date: June 26, 2008
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Norihiko Kubo
  • Publication number: 20080145100
    Abstract: A cleanerless image forming apparatus capable of reducing the density unevenness of halftone images, comprising a photosensitive member; charging roller means for uniformly charging the surface of the photosensitive member; an optical writing unit which is not shown on the drawings, for forming latent images on the surface of the photosensitive member after uniform charging thereof; a developing device for developing the latent image on the photosensitive member to obtain a toner image; a transfer unit for transferring the toner image on the surface of the photosensitive member to an intermediate transfer belt; and a brush member for trapping post-transfer residual toner adhering to the surface of the photosensitive member after passing through the transfer process by the transfer unit and before entering the developing process by the developing device, wherein the post-transfer residual toner is recovered within the developing device after re-transfer of the post-transfer residual toner within the brush memb
    Type: Application
    Filed: December 12, 2007
    Publication date: June 19, 2008
    Inventors: Yoshio SAKAGAWA, Tetsumaru Fujita, Yuji Nagatomo
  • Patent number: 7383003
    Abstract: A developing apparatus includes a developing roller for developing an image with a developer; a non-rotary magnet roll inside the roller; a blade; and an abutting member abutting against the roller, wherein the following expressions are satisfied: |Vs|>|Vdev|, |Br|/|B|?0.5, and L/(BH×R)?0.1, where |Vdev|: a DC component Vdev of a voltage applied to the roller, |Vs|: a DC component Vs of a voltage applied to the member, B(G): the magnetic flux density formed on the surface of the roller at the abutting position by the magnet roll, Br(G): the component of the magnetic flux density B(G) perpendicular to the surface of the roller, and L(mm): the abutting width between the roller and the member, BH(rad): the half value width of the component B?(G) horizontal to the surface of the roller, and R(mm): the radius of the roller.
    Type: Grant
    Filed: April 12, 2006
    Date of Patent: June 3, 2008
    Assignee: Canon Kabushiki Kaisha
    Inventors: Naoto Kichijima, Koichi Okuda, Yasushi Shimizu, Kenya Ogawa, Shuji Moriya, Kazunari Hagiwara
  • Publication number: 20080118272
    Abstract: An image forming apparatus includes a rotatable brush in contact with an image bearing member at a position downstream of transfer means and upstream of charging means in a rotational direction of the image bearing member. The rotational brush is configured to supply electrical charge to residual toner that remains on the image bearing member. The image forming apparatus executes a mode for removing toner particles attached to the brush by setting a peripheral speed of the brush to be lower than that of the image bearing member during an image forming time period and setting the peripheral speed of the brush to be higher than that of the image bearing member during at least part of a non-image forming time period.
    Type: Application
    Filed: November 6, 2007
    Publication date: May 22, 2008
    Applicant: CANON KABUSHIKI KAISHA
    Inventor: Isao Komatsu
  • Patent number: 7321741
    Abstract: An image forming apparatus includes a plurality of image forming stations and a transferring device. Each image forming station includes an image carrier for carrying an electrostatic image and a developing device for developing the electrostatic image with toner. The transferring device transfers toner images formed by the plurality of image forming stations to a transferring medium. The plurality of image forming stations include a transparent image forming station using transparent toner and color image forming stations using, for example, yellow, magenta, cyan, and black toners, respectively. The transparent image forming station includes a cleaning device that is in contact with the image carrier and picks up residual toner on the image carrier. The developing devices of the color image forming stations develop electrostatic images on the corresponding image carriers and simultaneously pick up residual toners on the corresponding image carriers.
    Type: Grant
    Filed: December 7, 2005
    Date of Patent: January 22, 2008
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tomoyuki Sakamaki, Hiroyuki Kidaka
  • Patent number: 7308214
    Abstract: An image forming apparatus includes: a plurality of development units having developing-agent carriers which are provided in correspondence to three or more developing agents, and developing electrostatic latent images on surfaces of image carriers to form developing-agent images on the image carriers; and a recovery unit that recovers the developing agent adhering to the developing-agent carrier during non-development operation. The recovery unit is provided for at least the development unit other than the development unit that transfers the developing-agent image first in sequence among the plurality of development units. When one of the plurality of development units performs development by the developing agent whose charge capability is higher than that of the developing agent of the development unit that transfers the developing-agent image later in sequence, the recovery unit starts recovery of the developing agent or performs recovery operation for improving recovery capability of the developing agent.
    Type: Grant
    Filed: September 29, 2005
    Date of Patent: December 11, 2007
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventors: Tomoaki Hattori, Yukiko Nakaya
  • Patent number: 7295796
    Abstract: A cleaningless image forming apparatus of the present invention uses spherical toner grains on surfaces of which a charge control agent and/or organic fine grains are present, thereby enhancing efficient image transfer. A brush roller collects, among toner grains left on a photoconductive drum after image transfer, toner grains of polarity opposite to preselected polarity and then releases them to the drum at preselected timing. The toner grains of opposite polarity are then transferred to an intermediate image transfer belt. When the toner grains of opposite polarity pass a charging zone assigned to a charge roller, a bias to the charge roller is interrupted or the charge roller is released from the drum.
    Type: Grant
    Filed: September 2, 2003
    Date of Patent: November 13, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Eisaku Murakami, Hideo Yoshizawa, Hiroyuki Nagashima, Yoshiyuki Kimura, Hideki Zemba, Eiji Kurimoto, Takeshi Uchitani, Toshio Koike, Masato Yanagida, Masami Tomita, Atsushi Sampe, Naohiro Kumagai, Takeshi Shintani, Masanori Kawasumi
  • Patent number: 7286777
    Abstract: An image forming device includes an image forming unit that includes an image carrier which carries an electrostatic latent image, a developing unit which forms a developing nip by contacting with the image carrier and develops the latent image by using toner, a transfer unit which forms a transferring nip by contacting with the image carrier and transfers a toner image onto a recording paper, and a first driving unit which rotates the image carrier, the developing unit and the transfer unit. The image forming device also includes a laser scanner unit that includes a polygon mirror and a second driving unit which rotates the polygon mirror.
    Type: Grant
    Filed: May 4, 2004
    Date of Patent: October 23, 2007
    Assignee: Murata Kikai Kabushiki Kaisha
    Inventor: Takahiro Sasai
  • Patent number: 7239831
    Abstract: An image forming apparatus includes an image bearing member; a charging device for electrically charging the image bearing member; a rotatable developer carrying member for carrying a developer to develop an electrostatic image formed on the image bearing member with the developer, the developer carrying member being supplied with a developing bias voltage including an AC voltage; non-rotatable magnetic field generating device, disposed inside the developer carrying member, for magnetically attracting the developer on the developer carrying member, wherein the developer carrying member has a surface elastic layer, and the developer carrying member is press-contacted to the image bearing member, and the developer is one component magnetic toner, and a maximum value of an absolute value of the developing bias voltage |V|max and a surface potential of the image bearing member charge by the charging device is Vd(V), satisfy, |V|max=|Vd|.
    Type: Grant
    Filed: December 15, 2004
    Date of Patent: July 3, 2007
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kazunari Hagiwara, Kouichi Okuda, Yasunori Chigono, Yasushi Shimizu, Hikaru Osada, Shuji Moriya
  • Patent number: 7228088
    Abstract: In an image forming apparatus of the present invention capable of forming a full-color image by superposing a black toner image formed by a black image forming unit using a developing and simultaneous cleaning type developing unit over color toner images obtained by color image forming units using developing and simultaneous cleaning developing units arranged in tandem, adhered toners generated from the black image forming unit or the color image forming units to be recovered are all recovered by a same single cleaner.
    Type: Grant
    Filed: January 21, 2005
    Date of Patent: June 5, 2007
    Assignees: Kabushiki Kaisha Toshiba, Toshiba Tec Kabushiki Kaisha
    Inventor: Shoko Shimmura
  • Patent number: 7092649
    Abstract: An image forming apparatus has a charging member opposed to an outer circumferential surface of a rotating object to be charged. The image forming apparatus has a voltage applying section for applying a pulsating voltage Vsp between the charging member and the object to be charged. The pulsating voltage Vsp is obtained by superimposing a voltage component of a direct current on a voltage component that periodically changes. The image forming apparatus is made to satisfy a relation of Vpp?|Vth|, where Vpp is a peak-to-peak voltage value of the pulsating voltage Vsp and Vth is a charging start voltage value of the object to be charged. The relation prevents opposite charge from being imparted to residual toner on the object to be charged.
    Type: Grant
    Filed: August 24, 2004
    Date of Patent: August 15, 2006
    Assignee: Konica Minolta Business Technologies, Inc.
    Inventors: Akira Hirota, Kentaro Katori, Masahiko Matsuura
  • Patent number: 7031641
    Abstract: An image-forming apparatus includes a pre-charge exposure device which removes electric charge from a photoconductor drum to increase a potential contrast between the surface of the photoconductor drum and the surface of a charge roller in an upstream region of a nip region between the photoconductor drum and the charge roller in the rotating direction of the photoconductor drum, so that toner accumulating in an upstream region of the nip region in the rotating direction of the photoconductor drum is restrained and prevented from being discharged onto an image-forming region. When the toner accumulating in the upstream region of the nip region in the rotating direction of the photoconductor drum is to be discharged onto a non-image-forming region, the pre-charge exposure device is turned off so that the potential contrast decreases.
    Type: Grant
    Filed: April 28, 2004
    Date of Patent: April 18, 2006
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hisashi Nakahara, Yasunori Chigono, Yasuhiro Nakata
  • Patent number: 6996355
    Abstract: An image formation apparatus has developing agent charging device situated downstream in the direction of motion of a photosensitive drum from a transfer roller and upstream from a charging roller, for charging residual developing agent remaining on the photosensitive drum. Applying AC voltage to the charging roller is started before a portion on the face of the photosensitive drum where application of voltage to the developing agent charging device has started reaches a position of coming into contact with the charging roller, and applying AC voltage to the charging device is ended after the portion on the face of the photosensitive drum where application of voltage to the developing agent charging device has ended reaches a position of coming into contact with the charging roller. This configuration prevents adhesion of developing agent to the photosensitive drum and charging roller, avoids resultant substandard images, and provides high-quality images for prolonged periods.
    Type: Grant
    Filed: October 16, 2003
    Date of Patent: February 7, 2006
    Assignee: Canon Kabushiki Kaisha
    Inventor: Yasunari Watanabe
  • Patent number: 6968149
    Abstract: There is provided a simply structured, cleanerless image forming apparatus capable of suppressing occurrence of filming without significant remodeling. An image forming apparatus 100 according to the present invention comprises a plurality of image forming units 100a, 100b, 100c, and 100d for forming toner images of corresponding colors on photoconductor drums 3a, 3b, 3c, and 3d according to a cleanerless system. These image forming units respectively have adhered toner film cleaners 1a, 1b, 1c, and 1d each of which touches a surface of the photoconductor and mechanically cleans the surface at every cleaning timing for cleaning the surface of the photoconductor. The adhered toner film cleaner does nothing during image formation, but cleans the photoconductor surface only at cleaning timing when the image formation is complete for the specified number of sheets. Accordingly, it is possible to decrease filming without affecting the photoconductor's life.
    Type: Grant
    Filed: March 12, 2003
    Date of Patent: November 22, 2005
    Assignees: Kabushiki Kaisha Toshiba, Toshiba Tec Kabushiki Kaisha
    Inventors: Masashi Takahashi, Takeshi Watanabe, Shinji Aoki
  • Patent number: 6944416
    Abstract: A cleaner-less image forming apparatus serves to prevent excessive expellation of toner from a photosensitive drum at the time of application of a bias voltage. A developer charging member for charging residual toner on the photosensitive drum is disposed in contact with the photosensitive drum at a location downstream of a transfer device and upstream of a charging device in a direction in which the photosensitive drum is rotating. A DC voltage of a polarity opposite to a normal charging polarity of the developer is applied to the developer charging member and has a slope whose absolute value at the start of voltage application is selectable from a first value and a second value which is greater than the first value.
    Type: Grant
    Filed: September 26, 2003
    Date of Patent: September 13, 2005
    Assignee: Canon Kabushiki Kaisha
    Inventor: Yasunari Watanabe
  • Patent number: 6907211
    Abstract: An image forming apparatus is provided, which includes: an image bearing member, a charging member for charging the image bearing member, the charging member bearing electrically conductive particles that contact the image bearing member, and a developer carrying member for carrying a developer provided with toner and electrically conductive particles, the developer carrying member being applied a voltage to develop an electrostatic image formed on the image bearing member with the developer and being capable of collecting a residual developer on the image bearing member, wherein the developer carrying member is provided in such a manner that the developer carrying member opposes the image bearing member via a gap of 150 ?m or more and 250 ?m or less.
    Type: Grant
    Filed: July 9, 2001
    Date of Patent: June 14, 2005
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masahiro Yoshida, Junichi Kato, Yasushi Shimizu, Hiroshi Sato, Hiroyuki Oba
  • Patent number: 6879793
    Abstract: To provide a method for forming images in which the image bearing member and the toner carrying member are arranged with a gap of 100 ?m to 250 ?m, and the equation (1) and equation (2) are satisfied. (1) 22?(the frequency of the alternating current component of the alternating electric field/the peripheral speed of the toner carrying member)×the maximum electric field intensity at the time of developing?1.20. (2) 8?(the frequency of the alternating current component of the alternating electric field/the peripheral speed of toner carrying member)×(the fluidity index of Carr/the floodability index of Carr)?50. According to the method for forming images of the present invention, it is possible to obtain a high quality image without generating fog and light shielding while attaining a uniform halftone with a high image density even over long-term.
    Type: Grant
    Filed: June 18, 2003
    Date of Patent: April 12, 2005
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tatsuhiko Chiba, Michihisa Magome, Keiji Komoto, Kaori Hiratsuka, Takeshi Kaburagi
  • Publication number: 20040228658
    Abstract: The present removing system has an object to remover a left-over toner that is accumulated on a brush that touches a left-over toner on a photoreceptor. More specifically, the present removing system is so arranged that an alternating voltage (superimposing voltage) on which a positive direct current voltage is superimposed is applied onto a conductive brush in accordance with a user's instruction. With this arrangement, even if a positively electrified left-over toner is accumulated on the conductive brush, it is possible to remove the positively electrified left-over toner accumulated on the conductive brush, because a voltage value (positive) applied on the conductive brush in a moment is large. Moreover, because a voltage of the conductive brush becomes negative in a moment, it is possible to remove a negatively electrified left-over toner attached on the conductive brush.
    Type: Application
    Filed: September 25, 2003
    Publication date: November 18, 2004
    Inventors: Syohji Tomita, Atsuyuki Katoh, Hiroshi Onda, Takashi Mukai, Hiroshi Ishii
  • Publication number: 20040228657
    Abstract: There is provided a simply structured, cleanerless image forming apparatus capable of suppressing occurrence of filming without significant remodeling.
    Type: Application
    Filed: June 29, 2004
    Publication date: November 18, 2004
    Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA TEC KABUSHIKI KAISHA
    Inventors: Masashi Takahashi, Takeshi Watanabe, Shinji Aoki
  • Publication number: 20040223784
    Abstract: An image-forming apparatus includes a pre-charge exposure device which removes electric charge from a photoconductor drum to increase a potential contrast between the surface of the photoconductor drum and the surface of a charge roller in an upstream region of a nip region between the photoconductor drum and the charge roller in the rotating direction of the photoconductor drum, so that toner accumulating in an upstream region of the nip region in the rotating direction of the photoconductor drum is restrained and prevented from being discharged onto an image-forming region. When the toner accumulating in the upstream region of the nip region in the rotating direction of the photoconductor drum is to be discharged onto a non-image-forming region, the pre-charge exposure device is turned off so that the potential contrast decreases.
    Type: Application
    Filed: April 28, 2004
    Publication date: November 11, 2004
    Applicant: Canon Kabushiki Kaisha
    Inventors: Hisashi Nakahara, Yasunori Chigono, Yasuhiro Nakata
  • Patent number: 6810223
    Abstract: A method of forming an image in a developing apparatus of an image forming apparatus and an image forming apparatus including a retrieving/auxiliary developing roller being in contact with the circumference of the photosensitive drum to retrieve or collect toner remaining on a region other than an image region of the circumference of the photosensitive drum and to first develop the latent electrostatic image, a first toner layer control member uniformly re-distributing the remnant toner and electrifying toner on the circumference of the retrieving/auxiliary developing roller and a developing roller having a gap with the circumference of the photosensitive drum to secondly develop the firstly developed latent electrostatic image so as to completely visualize the latent electrostatic image, a supply roller supplying toner to the developing roller, and a second toner layer control member for regularly coating the toner, which is supplied by the supply roller, throughout the circumference of the developing roller
    Type: Grant
    Filed: September 30, 2002
    Date of Patent: October 26, 2004
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Jong-moon Eun, Duck-hee Lee
  • Patent number: 6807384
    Abstract: To provide an image forming apparatus improving discharging of a developer from charge providing member for providing charge to the developer remaining on an image bearing member to the image bearing member, the developer is charged from the charge providing member to the image bearing member. When a developer discharging region of the image bearing member is disposed at a charging position, charging member is applied with a voltage having a direct current component of an absolute value equal to or smaller than an absolute value of voltage applied to the charge providing member without an alternating current component.
    Type: Grant
    Filed: April 18, 2003
    Date of Patent: October 19, 2004
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kazuhiro Okubo, Masahide Kinoshita, Masaki Ojima, Motoki Adachi, Masao Uyama
  • Publication number: 20040202494
    Abstract: An image forming apparatus is provided, which includes: an image bearing member, a charging member for charging the image bearing member, the charging member bearing electrically conductive particles that contact the image bearing member, and a developer carrying member for carrying a developer provided with toner and electrically conductive particles, the developer carrying member being applied a voltage to develop an electrostatic image formed on the image bearing member with the developer and being capable of collecting a residual developer on the image bearing member, wherein the developer carrying member is provided in such a manner that the developer carrying member opposes the image bearing member via a gap of 150 &mgr;m or more and 250 &mgr;m or less.
    Type: Application
    Filed: July 9, 2001
    Publication date: October 14, 2004
    Inventors: Masahiro Yoshida, Junichi Kato, Yasushi Shimizu, Hiroshi Sato, Hiroyuki Oba
  • Patent number: 6778791
    Abstract: An image forming apparatus includes a rotatable image bearing member; a charging rotatable member, contactable to the image bearing member at a contact position, for electrically charging the image bearing member, the charging rotatable member being rotatable for counterdirectional peripheral movement relative to rotation of the image bearing member at the contact position; developing means for developing an electrostatic image formed on the image bearing member with a developer, the developing means being capable of collecting a residual developer from the image bearing member; and wherein start of rotation of the charging rotatable member is simultaneous with or prior to start of rotation of the image bearing member.
    Type: Grant
    Filed: April 26, 2002
    Date of Patent: August 17, 2004
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yasushi Shimizu, Junichi Kato, Hiroshi Satoh, Masahiro Yoshida, Hiroyuki Oba
  • Patent number: 6744994
    Abstract: An image forming apparatus includes an image bearing member, a first charging member for charging a residual developer on the image bearing member, a second charging member for charging the residual developer, an environmental condition detector, and a controller. The first charging member is disposed downstream of the transferring device and up stream of the charger, with respect to a movement direction of the image bearing member. A voltage having a polarity opposite to a polarity of the developer is applied to the first charging member. The second charging member is disposed downstream of the first charging member and upstream of the charger. A voltage having a polarity like a polarity of the developer is applied to the second charging member. The controller, in accordance with an output of the detector, controls at least one of the voltages applied to the first and second charging members.
    Type: Grant
    Filed: September 4, 2002
    Date of Patent: June 1, 2004
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tadanobu Yoshikawa, Yasunari Watanabe, Motoki Adachi
  • Patent number: 6721522
    Abstract: An image forming apparatus includes a transferring device for transferring, after a first color developer image is transferred onto an image receiving material in a first image forming station, a second color developer image onto the image receiving material in a second image forming station. A second developer carrying member of the second image forming station is capable of collecting a residual developer from a second image bearing member of the second image forming station simultaneously with a developing operation thereto. The moving direction of the second developer carrying member is opposite to a moving direction of the second image bearing member at a development position. A second charging device of the second image forming station includes a second charging member contactable to the second image bearing member, and the second charging member triboelectrically charges the residual developer on the second image bearing member to a regular polarity.
    Type: Grant
    Filed: July 29, 2002
    Date of Patent: April 13, 2004
    Assignee: Canon Kabushiki Kaisha
    Inventor: Tomomi Kakeshita
  • Patent number: 6654579
    Abstract: An image forming apparatus including an image carrier including a conductive support, at least a photoconductive layer formed on the conductive support, and a surface protection layer formed on the photoconductive layer and including a charge injection layer. Also included is a charge member for charging the image carrier in contact with the surface protection layer when applied with a voltage. Further, the surface protection layer has a diamond-like structure or an amorphous structure containing hydrogen with a volume resistance of 109 &OHgr;·cm to 1012 &OHgr;·cm and a Knoop hardness of 400 Kg/mm2 or greater, and the charging member includes magnetic particles for charging having a mean particle size ranging from 20 &mgr;m to 150 &mgr;m. Also, a light transmission of the surface protective layer is 50% or more of a wavelength of light used for exposing the image carrier.
    Type: Grant
    Filed: October 25, 2002
    Date of Patent: November 25, 2003
    Assignee: Ricoh Company, Ltd.
    Inventors: Masahiko Shakuto, Kei Yasutomi, Hirokatsu Suzuki, Nobutaka Takeuchi, Toshihiko Baba
  • Patent number: 6647225
    Abstract: A charging device includes a charging rotary member provided in contact with an image bearing member capable of bearing a toner for charging the image bearing member, in which a peripheral speed of the charging rotary member is different from a peripheral speed of the image bearing member, and the charging rotary member includes a surface layer frictionally charging the toner to a normal charging polarity.
    Type: Grant
    Filed: March 7, 2002
    Date of Patent: November 11, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventor: Tomomi Kakeshita
  • Patent number: 6640071
    Abstract: A cleaner-less type image forming machine for removing the toner accumulated in the memory removing brush, and improving the quality of the image forming onto the recording medium is provided. The image forming machine includes a photoconductive drum, a charge brush for charging the photoconductive drum, LED print head for forming an electrostatic latent image on the surface of the charged photoconductive drum, a developing roller for developing the electrostatic latent image on the surface of the photoconductive drum, a transferring roller for transferring a toner image on the photoconductive drum to a paper, a memory removing brush for removing the toner image remaining on the photoconductive drum, and a current detector for detecting current flowing through the memory removing member, wherein a cleaning sequence of the toner adhered to the memory removing member is carried out.
    Type: Grant
    Filed: November 8, 2001
    Date of Patent: October 28, 2003
    Assignee: Murata Kikai Kabushiki Kaisha
    Inventor: Naohiro Okada
  • Patent number: 6636715
    Abstract: To provide an amorphous Si photosensitive member and an image forming apparatus which form favorable images by preventing toner adhesion at a cleaning time. A photoconductive layer 102 containing amorphous Si is formed on an electrically conductive substrate 101 so that a surface of a photosensitive member has an average inclination &Dgr;a within a range of 0.12 to 1.0, more preferably 0.15 to 0.8 within a range of 10 &mgr;m×10 &mgr;m, and an electrically conductive substrate has surface roughness Ra within the range of 10 &mgr;m×10 &mgr;m is lower than 9 nm, preferably lower than 6 nm.
    Type: Grant
    Filed: May 22, 2001
    Date of Patent: October 21, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kunimasa Kawamura, Koji Yamazaki, Toshiyuki Ehara, Masaya Kawada, Tetsuya Karaki, Hironori Owaki
  • Patent number: 6611668
    Abstract: In order not to expel toner excessively when bias is applied, a cleanerless image forming apparatus includes a first developer charge amount controlling device 7, provided on a downstream side of a transfer device 5 in a moving direction of an image bearing member 1, e.g. a photosensitive drum, for applying a DC bias for making uniform a charge amount of residual developer remaining on the image bearing member 1, and/or a second developer charge amount controlling device 8, provided on a downstream side of the first developer charge amount controlling device 7 in a rotating direction of the image bearing member 1, for applying a DC bias for charging the residual developer in a normal polarity. An absolute value of a slope of the DC voltage applied to the first developer charge amount controlling device 7 and/or an absolute value of a slope of the DC voltage applied to the second developer charge amount controlling device 8 are equal to 2000 V/sec or smaller.
    Type: Grant
    Filed: August 30, 2002
    Date of Patent: August 26, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yasunari Watanabe, Motoki Adachi