Charging Patents (Class 399/168)
  • Publication number: 20090324289
    Abstract: According to various embodiments, there is a charging device including a first conductive layer disposed over a first dielectric layer; a second dielectric layer disposed over a first conductive layer, the second dielectric layer including a plurality of cavities, wherein each of the plurality of cavities exposes a portion of the first conductive layer; a plurality of micro-tips, wherein one of the plurality of micro-tips is disposed within each of the plurality of cavities and on the first conductive layer; a second conductive layer disposed over the second dielectric layer; and a system of interconnected air flow channels disposed in the second dielectric layer and connected to the cavities, such that air injected through an air inlet exits through the plurality of cavities. The charging device can also include one or more power supplies to apply bias voltages to the first and the second conductive layers.
    Type: Application
    Filed: June 30, 2008
    Publication date: December 31, 2009
    Applicant: XEROX CORPORATION
    Inventors: Fa-Gung FAN, Nancy JIA
  • Publication number: 20090311008
    Abstract: In an ion generating element, (i) an induction electrode and a heater electrode are provided away from each other on one surface of an insulating base material such that the induction electrode and the heater electrode are insulated from each other, (ii) a dielectric layer is provided on the surface of the insulating base material, and (iii) the dielectric layer has a length covering the insulating base material and the dielectric layer has openings above a ground terminal of the induction electrode and above a ground terminal and a power supply connection terminal of the heater electrode so that the terminals are exposed. As a result, it is possible to provide an ion generating element for generating ions along with creeping discharge, a charging device, and an image forming apparatus, each of which can be produced at low costs and prevent damages when unexpected troubles occur, and each of which is excellent in terms of safety.
    Type: Application
    Filed: June 9, 2009
    Publication date: December 17, 2009
    Inventors: Katsumi ADACHI, Shoutaro OKAMOTO, Toshiaki KAGAWA
  • Patent number: 7603063
    Abstract: An image forming apparatus includes an image bearing member, a charging roller and a pair of gap forming members. The image bearing member has a photoconductive surface including an image forming area for bearing an electrostatic latent image. The charging roller has a circular cross section with a first radius and a metallic core having a rotational axis of the charging roller, in parallel with and close to the image bearing member, and a charging surface for charging the photoconductive surface. The pair of gap forming members form a gap at least between the image forming area and the charging surface. Each of the pair of gap forming members have a circular cross section with a second radius such that a ratio of the second radius to the first radius is substantially constant through a whole rotational phase of the charging roller.
    Type: Grant
    Filed: December 26, 2006
    Date of Patent: October 13, 2009
    Assignee: Ricoh Company, Ltd.
    Inventors: Akio Kosuge, Hiroshi Ono, Kaoru Yoshino
  • Patent number: 7603062
    Abstract: A conductive member, including a long conductive supporting body, an electrical resistance adjusting layer, disposed on the outer circumferential surface of the conductive supporting body and having a reduced diameter section at either end, and a pair of gap maintaining members which are respectively fitted onto said reduced diameter sections of the electrical resistance adjusting layer. The outer circumferential surfaces of the gap maintaining members have a height differential with respect to the outer circumferential surface of the electrical resistance adjusting layer, in such a manner that when abutted against an image carrier, a prescribed gap is formed between the outer circumferential surface of the image carrier and the outer circumferential surface of the electrical resistance adjusting layer. An interval between the end faces of the electrical resistance adjusting layer and the faces of the gap maintaining members opposing the end faces satisfies a predetermined relationship.
    Type: Grant
    Filed: September 8, 2006
    Date of Patent: October 13, 2009
    Assignee: Ricoh Company, Ltd.
    Inventors: Eiji Shimojo, Masanori Kawasumi, Yoshiyuki Kimura, Masahiko Satoh, Takeshi Uchitani, Hideki Zemba, Yutaka Narita, Shunichi Hashimoto, Eisaku Murakami, Shin Kayahara
  • Publication number: 20090253062
    Abstract: Present embodiments pertain to an improved electrostatographic imaging member having low contact friction surfaces to ease sliding mechanical interaction and suppressing abrasion/wear failure and methods of preparing thereof. The improved imaging member has layers comprising one or two low surface energy polymeric materials that enhance the physical and mechanical functions and reduce the layers surface contact friction of the imaging member to extend service life.
    Type: Application
    Filed: April 7, 2008
    Publication date: October 8, 2009
    Applicant: XEROX CORPORATION
    Inventor: Robert C. U. Yu
  • Patent number: 7596344
    Abstract: A charging unit is disclosed capable of reducing undue variation and fluctuation margin of a charging gap, and controlling accurately the proper gap durably over the change of environmental conditions, which is suitably incorporated into an image forming apparatus. The charging unit is configured to charge an image bearing member in a non-contact arrangement, including a charging roller provided with a core shaft, a charging member formed of electroconductive resin integrally disposed on the periphery of the core shaft, and gap holding members formed of insulating resin each disposed at respective ends of the charging member outside an image forming region. The control of the charging gap is feasible by either forming the gap with a charging member having such a materials condition as to satisfy the relation, |G30?G10|×5<G20, where G10, G20 and G30 are the gap averages at 10°, 20° and 30° C.
    Type: Grant
    Filed: January 4, 2008
    Date of Patent: September 29, 2009
    Assignee: Ricoh Company, Ltd.
    Inventor: Akio Kosuge
  • Publication number: 20090232530
    Abstract: An apparatus includes an image bearing member for carrying an image; an intermediary transfer member for receiving the image; a primary transfer member for transfer of the image onto the intermediary transfer member in a primary transfer station; a secondary transfer member for transfer of the image onto a transfer material in a secondary transfer station; a first charging member for charging toner remaining in a region upstream of the primary transfer station and downstream of the secondary transfer station; and a second charging member for charging the toner remaining in a region upstream of the primary transfer station and downstream of the first charging member. The first charging member rubs a surface of, and the second charging member moves in contact with, the intermediary transfer member, to transfer the toner remaining on the intermediary transfer member to the image bearing member simultaneously with the primary transfer.
    Type: Application
    Filed: February 24, 2009
    Publication date: September 17, 2009
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Seiji Saito, Takuma Abe, Masaru Shimura, Ken Nakagawa, Kenji Kanari, Takamitsu Soda, Takaaki Akamatsu, Kazuhiro Doda, Takashi Shimada, Shuuichi Tetsuno
  • Publication number: 20090220279
    Abstract: An ion generating element of the present invention includes a discharge electrode and an inductive electrode, both of which are provided so as to face each other with a dielectric body sandwiched therebetween, and a heater electrode which warms the ion generating element by Joule heat produced because of a passage of an electrical current. A distance between the discharge electrode and the heater electrode is larger than that between the discharge electrode and the inductive electrode, and further a shield electrode having a connection for ground is provided between the heater electrode and the inductive electrode on a surface of the dielectric body at a side on which the inductive electrode is provided. Hence, it is possible to prevent a leak to the heater electrode at low cost, while giving consideration towards safety.
    Type: Application
    Filed: February 24, 2009
    Publication date: September 3, 2009
    Inventor: Katsumi ADACHI
  • Patent number: 7583914
    Abstract: A charge member that can reduce charge irregularities of a member to be charged caused by variations in the gap between the member to be charged and the charge member even when using a member to be charged (photosensitive member, and the like) that has circumferential fluctuations. The charge member which is arranged electrically without making contact with the member to be charged, and which charges the member to be charged by applying AC voltage superimposed on DC voltage, and which is formed of a rotatable roller, is arranged electrically without making contact with the member to be charged having circumferential fluctuations of 4 to 80 ?m within the image formation area, and which has a plurality of stage differences with a height difference of 2 to 30 ?m on the surface of the roller; and the stage differences in the area opposing the member to be charged are five to thirty in relation to a distance of 0.5 mm in the circumferential direction of the roller.
    Type: Grant
    Filed: October 27, 2006
    Date of Patent: September 1, 2009
    Assignee: Ricoh Company, Ltd.
    Inventors: Kumiko Hatakeyama, Toshiyuki Kabata
  • Patent number: 7583915
    Abstract: An image forming apparatus includes a rotatable image carrying member, on a surface of which an electrostatic latent image is formed, and a charging roll that is in contact with the image carrying member to charge the surface of the image carrying member to a prescribed potential. The charging roll has, in non-image forming areas in both end parts in an axial direction of the charging roll, large diameter parts having a larger outer diameter than an outer diameter of a center part of the charging roll, and small diameter parts having a smaller outer diameter than the outer diameter of the center part inside the large diameter parts in the axial direction. Differences in outer diameter of the large diameter part and the small diameter part from the outer diameter of the center part each is approximately 0.25% or less of the outer diameter of the center part.
    Type: Grant
    Filed: January 24, 2007
    Date of Patent: September 1, 2009
    Assignee: Fuji Xerox Co., Ltd.
    Inventor: Akihiro Ida
  • Patent number: 7555243
    Abstract: A charging member, which can be provided in a process cartridge and/or in an image forming apparatus, includes a conductive supporting member, an electrical resistance control layer formed on an outer circumferential surface of the conductive supporting member, and a nonconductive gap retaining member configured to retain a gap between the conductive supporting member and an image carrying member closely disposed to each other to have a constant distance. At least a portion of the nonconductive gap retaining member is mounted on the electrical resistance control layer at both ends of the conductive supporting member, and a circumference of the nonconductive gap retaining member projects from the electrical resistance control layer. An amount of projection of the gap retaining member from the electrical resistance control layer decreases as the gap retaining member tapers in a direction toward a center of an image formation region.
    Type: Grant
    Filed: July 6, 2007
    Date of Patent: June 30, 2009
    Assignee: Ricoh Company, Ltd.
    Inventors: Masahiko Satoh, Masanori Kawasumi, Yoshiyuki Kimura, Eisaku Murakami, Hideki Zemba, Takeshi Uchitani, Shin Kayahara, Shunichi Hashimoto, Eiji Shimojo
  • Publication number: 20090128103
    Abstract: An AC high voltage power supply device includes a comparison circuit configured to compare a first signal of a sinusoidal waveform and a second signal of a triangular waveform; a switching amplifier circuit configured to perform a switching operation based on a comparison result signal output from the comparison circuit to perform signal amplification; a conversion circuit configured to convert a waveform of a switch signal output from the switching amplifier circuit into a sinusoidal waveform; a transformer configured to boost a voltage of a converted signal output from the conversion circuit; and a control circuit configured to perform feedback control on the first signal input to the comparison circuit based on a monitoring signal including an input signal or an output signal of the transformer, so that a peak level of the output signal of the transformer becomes a desired peak level.
    Type: Application
    Filed: November 18, 2008
    Publication date: May 21, 2009
    Inventor: Hiroo NODA
  • Publication number: 20090123176
    Abstract: The present invention relates to a polyvinyl acetal resin having a specific repeating structural unit, an electrophotographic photosensitive member using the polyvinyl acetal resin, and a process cartridge and an electrophotographic apparatus each having the electrophotographic photosensitive member.
    Type: Application
    Filed: December 5, 2006
    Publication date: May 14, 2009
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Masato Tanaka, Atsushi Fujii, Yuka Ishiduka, Masataka Kawahara, Masaki Nonaka
  • Publication number: 20090116872
    Abstract: A charging device including an electron discharging device for forming a latent electrostatic image on an image bearing member and containing an sp3 bonding material and an electroconductive portion.
    Type: Application
    Filed: April 19, 2006
    Publication date: May 7, 2009
    Inventors: Naomi Sugimoto, Yukimichi Someya, Sadayuki Iwai, Katsufumi Kumano, Eiichi Ohta
  • Patent number: 7515851
    Abstract: Provided are an electron emitter continuously emitting electrons stably even in the atmosphere, a charger using the electron emitter, and a charging method using the charger. The electron emitter includes a electron emitting element consisting of a first electrode, a second electrode, and a semiconductor layer formed therebetween, and a power supply for alternately applying a positive voltage enabling electron emission and a negative voltage having a polarity opposite to the positive voltage. At least a part of the surface on the first electrode side of the semiconductor layer is formed of a porous semiconductor layer. Electrons captured in the porous semiconductor layer in the course of electron emission with application of a positive voltage disturb electron emission from the electron emitting element. Such electrons, however, are removed by application of a negative voltage.
    Type: Grant
    Filed: April 28, 2004
    Date of Patent: April 7, 2009
    Assignees: Sharp Kabushiki Kaisha, Nobuyoshi Koshida
    Inventors: Hiroyuki Hirakawa, Tadashi Iwamatsu, Nobuyoshi Koshida
  • Patent number: 7509076
    Abstract: Charging devices, electrostatic imaging devices, and methods generate a charging waveform having a DC bias component and an AC component for charging the imaging surface of a charge retentive member, the AC component having a substantially squarewave waveform.
    Type: Grant
    Filed: March 7, 2007
    Date of Patent: March 24, 2009
    Assignee: Xerox Corporation
    Inventors: Michael F. Zona, Christopher A. Dirubio, Aaron Michael Burry, Palghat S. Ramesh
  • Publication number: 20090074462
    Abstract: An optical scanning device including a first housing including a rotating deflector configured to deflect a light beam from at least one light source to scan a surface to be scanned with a deflected light beam, a second housing including one or more reflecting mirrors, and three supporting members configured to support the second housing relative to an image forming apparatus. The first housing is mounted inside the second housing, and mounts to fix the first housing to the second housing are positioned substantially on or within sides of a triangle formed by the three supporting members.
    Type: Application
    Filed: September 12, 2008
    Publication date: March 19, 2009
    Inventor: Kozo YAMAZAKI
  • Publication number: 20090052939
    Abstract: The invention provides a charging device used in an image forming apparatus such as a copier, a fax machine, a printer or the like, the charging device including: a gold-plated discharge wire for charging an image carrier such as a photoconductive member or the like; and a cleaning member, having an abrasive, for cleaning the discharge wire, with the gold plating being maintained over time satisfactorily, and provides a process cartridge having this charging device. The cleaning member has an abrasive containing alumina and/or silicon, the grain size of which ranges from #6000 to #8000. The discharge wire is a tungsten wire on which a plating film is formed by gold plating, such that the thickness of the plating film is not smaller than 1.5 ?m, and the diameter of the tungsten wire is not smaller than 30 ?m.
    Type: Application
    Filed: August 18, 2008
    Publication date: February 26, 2009
    Inventors: Kaoru Yoshino, Takaya Muraishi, Akio Kosuge, Takeshi Shintani, Yasushi Akiba, Satoshi Hatori
  • Patent number: 7493064
    Abstract: An electrical conductive member is configured to prevent a shape distortion in gap retaining members caused by that the gap retaining members are fitted to an end surface of an electric resistance adjusting layer, and to be able to maintain a gap between the electric residence adjusting layer and an image carrier for a long-term in a constant state with a high accuracy.
    Type: Grant
    Filed: November 22, 2006
    Date of Patent: February 17, 2009
    Assignee: Ricoh Company, Ltd.
    Inventors: Yutaka Narita, Makoto Nakamura, Toshio Kojima, Tadaaki Hattori, Taisuke Tokuwaki, Tadayuki Oshima, Hiroki Furubayashi
  • Publication number: 20090039244
    Abstract: A surface of a discharge electrode of an ion generating device of the present invention, other than a surface in contact with a dielectric body, is coated with a protective layer made of a metal that is gold or a combination of gold and nickel. This allows the ion generating device to generate ions evenly and stably, and to have a longer life.
    Type: Application
    Filed: August 4, 2008
    Publication date: February 12, 2009
    Inventors: Toshiaki Kagawa, Shogo Yokota, Katsumi Adachi, Masashi Hirai
  • Publication number: 20090041501
    Abstract: A charging device (10) includes electrospray means for inducing electrospraying through application of a voltage to an incoming liquid (11), in order to produce charged liquid droplets (13). The device (10) charges a photoreceptor drum (1) by means of the liquid droplets (13). Hence, the invention provides a charging device capable of reducing ozone production while preventing the charging device and the electrostatic latent image carrier from degrading or wearing out from friction between the device and the carrier and provides also an image forming device incorporating the charging device.
    Type: Application
    Filed: November 17, 2006
    Publication date: February 12, 2009
    Applicant: SHARP KABUSHIKI KAISHA
    Inventors: Tadashi Iwamatsu, Hirofumi Kanda
  • Publication number: 20090001280
    Abstract: In an ion generating element according to the present invention, a discharge electrode and an inductive electrode are provided to face each other with a dielectric body therebetween, and a heater electrode for producing heat with Joule heat generated by electrification and the inductive electrode are provided independently on the same surface of the dielectric body. Further, the heater electrode and the inductive electrode are connected and positioned such that a heater current does not flow into the inductive electrode. Thereby, it is possible to appropriately set a size or a shape of the inductive electorde according to a condition at low costs, allowing stable and effective discharge.
    Type: Application
    Filed: June 27, 2008
    Publication date: January 1, 2009
    Inventor: Katsumi ADACHI
  • Patent number: 7468208
    Abstract: An imaging member containing a substrate, and a layer containing a polytetrafluoroethylene and a polyol ester, and an image forming apparatus for forming images on a recording medium including the imaging member above, a development component to apply a developer material to said charge-retentive surface to develop said electrostatic latent image to form a developed image on said charge-retentive surface; a transfer component for transferring said developed image from said charge-retentive surface to another member or a copy substrate; and a fusing member to fuse said developed image to said copy substrate.
    Type: Grant
    Filed: July 28, 2005
    Date of Patent: December 23, 2008
    Assignee: Xerox Corporation
    Inventors: Jin Wu, Geoffrey M T. Foley, Jodie L. Watson, Liang-Bih Lin, Edward C. Savage, Robert P. Altavela, Linda Ferrarese, Marc J. Livecchi
  • Patent number: 7466942
    Abstract: In accordance with the invention, there is an electrophotographic charging device including a first electrode, a second electrode adjacent the first electrode, a plurality of nanostructures adhering to the first electrode, and voltage supplies electrically connected to the first electrode and the second electrode, wherein the voltage difference between the first electrode and the second electrode creates a high electric field at the nanostructures to cause charge species generation that is deposited on a receptor.
    Type: Grant
    Filed: April 6, 2006
    Date of Patent: December 16, 2008
    Assignee: Xerox Corporation
    Inventors: Michael F. Zona, Joseph A. Swift, Dan A. Hays
  • Publication number: 20080279588
    Abstract: A conductive member includes a conductive supporting member provided facing an image bearing member and including a continuous or discontinuous fixing groove provided in the vicinity of each of both ends of the conductive supporting member in a peripheral direction thereof, an electrical resistance adjusting layer formed on the conductive supporting member and including a step portion which includes at least one step disposed in the vicinity of each of the both ends of the electrical resistance adjusting member, and gap retainers each provided to the step portion and including a cylinder portion which contacts at least one surface of the step portion, and an end plate so that a predetermined gap is formed between the image bearing member and the electrical resistance adjusting layer. The end plate contacts at least one surface of the step portion and fits into the fixing groove.
    Type: Application
    Filed: May 9, 2008
    Publication date: November 13, 2008
    Inventors: Yutaka Narita, Makoto Nakamura, Taisuke Tokuwaki, Tadaaki Hattori, Tadayuki Oshima, Hiroki Furubayashi
  • Publication number: 20080241718
    Abstract: A method and device for receiving a used web of transfer foil on a wind-up reel overcome the disadvantage of telescoping of the wound-up web of transfer foil on the wind-up reel, which tends to increase as a used web of transfer foil continues to be fed to the wind-up reel. Telescoping is at least reduced by providing a device for receiving a used web of transfer foil with at least one dielectric layer, causing web regions adjacent each other in the radial direction on the wind-up reel to adhere to each other due to electrostatic forces. At least one charging device for charging the dielectric layer of the web of transfer foil is provided in a transfer foil web region upstream of the wind-up reel, to charge the used web of transfer foil. The charging device substantially extends over the entire width of the web of transfer foil.
    Type: Application
    Filed: March 27, 2008
    Publication date: October 2, 2008
    Applicant: HEIDELBERGER DRUCKMASCHINEN AG
    Inventor: Alexander Weber
  • Publication number: 20080219703
    Abstract: A conductive member includes a conductive supporter, an electric resistance adjusting layer formed on the conductive supporter and gap retaining members which are of a different material from that of the electric resistance adjusting layer and are disposed respectively at both ends of the electric resistance adjusting layer for contacting an image carrier so as to maintain a predetermined gap between the electric resistance adjusting layer and the image carrier, wherein the electric resistance adjusting layer is made from a resin composition containing a thermoplastic resin containing an ether group, an organic phosphonium salt and a fluorine-containing organic anion salt.
    Type: Application
    Filed: March 7, 2008
    Publication date: September 11, 2008
    Inventors: Tadayuki OSHIMA, Hiroki Furubayashi, Taisuke Tokuwaki, Yutaka Narita, Makoto Nakamura
  • Publication number: 20080219701
    Abstract: Charging devices, electrostatic imaging devices, and methods generate a charging waveform having a DC bias component and an AC component for charging the imaging surface of a charge retentive member, the AC component having a substantially squarewave waveform.
    Type: Application
    Filed: March 7, 2007
    Publication date: September 11, 2008
    Applicant: XEROX CORPORATION
    Inventors: Michael F. ZONA, Christopher A. DIRUBIO, Aaron Michael BURRY, Palghat S. RAMESH
  • Publication number: 20080219702
    Abstract: A disclosed image forming apparatus includes an image carrier; one or more charging units configured to charge the image carrier in preparation for formation of each of plural latent images corresponding to toner images of different colors; a latent image forming unit configured to expose non-image areas on the charged image carrier to form each of the latent images; and developing units configured to develop the corresponding latent images in sequence with toners of the corresponding colors to form the toner images and thereby to form a color toner image composed of the toner images of the different colors on the image carrier, the toners having polarity opposite to that of the charged image carrier.
    Type: Application
    Filed: March 5, 2008
    Publication date: September 11, 2008
    Inventors: Takeo TSUKAMOTO, Katsuhiro Aoki, Kei Yasutomi, Hitoshi Maruyama, Masanori Saitoh, Katsuaki Miyawaki
  • Patent number: 7403735
    Abstract: An image formation apparatus using an elecrophotographic process for obtaining a high quality image with tone value R2 of equal to or more than 0.98 is provided. The resolution for light-writing is equal to or more than 1200 dpi and/or light-writing is performed based on image data formed by applying halftone processing at a line frequency of equal to or more than 200 lpi. Light-writing means is accomplished with a laser light beam with a beam diameter equal to or less than 35 ?m. The photoconductor includes a charge generating layer containing a charge generating material and a charge transfer layer containing a charge transfer material laminated on a conductive support. The ionization potential of the charge generating material Ip(CG) and ionization potential of the charge transfer material Ip(CT) satisfy the relationship of Ip(CG)?Ip(CT).
    Type: Grant
    Filed: January 24, 2003
    Date of Patent: July 22, 2008
    Assignee: Ricoh Company, Ltd.
    Inventors: Kei Yasutomi, Yasuo Suzuki
  • Patent number: 7398035
    Abstract: Electrophotographic charging devices and methods for charging a receptor with a solid state charging device are disclosed. In an exemplary embodiment, the solid state charging device can include a dielectric layer, a first electrode disposed adjacent to a first surface of the dielectric layer, and a second electrode having a first surface disposed adjacent to a second surface of the dielectric layer. The solid state charging device can further include a plurality of nanostructures each having an end in electrical contact with a second surface of the second electrode. The exemplary solid state charging devices including the nanostructures can use less voltage than conventional charging devices, produce a reduced amount of oxidizing agents, such as, ozone and NOx, and/or operate at a lower temperature.
    Type: Grant
    Filed: April 6, 2006
    Date of Patent: July 8, 2008
    Assignee: Xerox Corporation
    Inventors: Michael F. Zona, Joseph A. Swift, Dan A. Hays, John S. Facci
  • Patent number: 7397032
    Abstract: Electrophotographic charging devices that can be used to charge or discharge, for example, a receptor in the electrophotographic process are provided. According to various embodiments, the exemplary charging devices can include a coronode disposed opposing and spaced apart from a receptor, and a plurality of nanostructures, wherein each of the plurality of nanostructures has an end, edge, or side in electrical contact with the coronode. The exemplary charging devices including the nanostructures can use less power, i.e. voltage and/or current than conventional charging devices and produce a reduced amount of oxidizing agents, such as, ozone and NOx. The nanostructures can serve to increase the intensity of the local electric fields for more efficient charge generation at reduced voltages.
    Type: Grant
    Filed: April 6, 2006
    Date of Patent: July 8, 2008
    Assignee: Xeorox Corporation
    Inventors: Michael F. Zona, Joseph A. Swift, Dan A. Hays
  • Patent number: 7389070
    Abstract: An image forming apparatus includes: an image supporting member; a charge roller for charging the image supporting member; a gap setting member disposed on the charge roller for setting a gap between the image supporting member and the charge roller; and a pressing member disposed at a position corresponding to the gap setting member for pressing the charge roller against the image supporting member. Accordingly, it is possible to form a constant gap between the charge roller and the image supporting member, thereby consistently charging the image supporting member.
    Type: Grant
    Filed: February 2, 2006
    Date of Patent: June 17, 2008
    Assignee: Oki Data Corporation
    Inventor: Akihito Onishi
  • Patent number: 7366447
    Abstract: Flanges are pressed into opposite ends of a photoreceptor drum. A noncontact charging roller is arranged so as to face, but have no direct contact with, the photoreceptor drum. On both end portions of the noncontact charging roller, spacers are provided for maintaing a gap between the photoreceptor drum and the noncontact charging roller. The spacers are of tape form and wound around the noncontact charging roller. Winding positions of the spacers are distant by more than an effective projection length of each of the flanges from respective opposite ends of the charging roller.
    Type: Grant
    Filed: March 10, 2004
    Date of Patent: April 29, 2008
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Takashi Mukai, Syohji Tomita, Hiroshi Onda, Atsuyuki Katoh, Hiroshi Ishii, Yoshinobu Okumura
  • Patent number: 7340200
    Abstract: A charging unit is disclosed capable of reducing undue variation and fluctuation margin of a charging gap, and controlling accurately the proper gap durably over the change of environmental conditions, which is suitably incorporated into an image forming apparatus. The charging unit is configured to charge an image bearing member in a non-contact arrangement, including a charging roller provided with a core shaft, a charging member formed of electroconductive resin integrally disposed on the periphery of the core shaft, and gap holding members formed of insulating resin each disposed at respective ends of the charging member outside an image forming region. The control of the charging gap is feasible by either forming the gap with a charging member having such a materials condition as to satisfy the relation, |G30?G10|×5<G20, where G10, G20 and G30 are the gap averages at 10°, 20° and 30° C.
    Type: Grant
    Filed: January 5, 2005
    Date of Patent: March 4, 2008
    Assignee: Ricoh Company, Ltd.
    Inventor: Akio Kosuge
  • Publication number: 20080038016
    Abstract: A conductive member to be disposed so as to abut on an image carrier is provided. The conductive member includes an elongate conductive supporter, an electrical resistance adjusting layer formed on a circumferential surface of the supporter, and a pair of gap maintaining members provided respectively to the two ends of the adjusting layer. A gap with a certain clearance between an outer circumferential surface of the adjusting layer and an outer circumferential surface of the image carrier provided in parallel to the adjusting layer is formed. A stepped portion is formed in a joint section between the adjusting layer and each of the gap maintaining members with the joint section. An inclination is formed so as to be continuously inclined from the outer circumferential surface of each of the gap maintaining members to the outer circumferential surface of the adjusting layer in the stepped portion.
    Type: Application
    Filed: August 10, 2007
    Publication date: February 14, 2008
    Inventors: Taisuke Tokuwaki, Yutaka Narita, Toshio Kojima, Tadaaki Hattori, Makoto Nakamura, Tadayuki Oshima, Hiroki Furubayashi
  • Publication number: 20080031642
    Abstract: An electrophotographic photoreceptor comprises: an electroconductive support; and a photosensitive layer on the electroconductive support, wherein the photosensitive layer comprises a functional layer, the functional layer comprising: a compound having a triple bond and a hydroxyl group in a molecule; and a cured product of a curable resin.
    Type: Application
    Filed: March 7, 2007
    Publication date: February 7, 2008
    Applicant: FUJI XEROX CO., LTD.
    Inventors: Wataru Yamada, Katsumi Nukada
  • Patent number: 7327965
    Abstract: Charging unit(s) is/are made versatile enough to be used in a plurality of image forming apparatus models having different processing speeds. Furthermore, in the context of an electrophotographic image forming apparatus permits selective switching between/among processing speeds, two charging units 5a, 5a having mutually identical configuration (e.g., charging units having case width 14 mm) are arranged within a single image forming unit (e.g., black image forming station Sa), the number of these two charging units 5a, 5a that is/are driven being switched in correspondence to processing speed(s) so as to make it possible for all of the charging units at image forming apparatus 100 to be accommodated by the same model.
    Type: Grant
    Filed: March 28, 2005
    Date of Patent: February 5, 2008
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Toshiaki Ino
  • Publication number: 20080008499
    Abstract: A charging member, which can be provided in a process cartridge and/or in an image forming apparatus, includes a conductive supporting member, an electrical resistance control layer formed on an outer circumferential surface of the conductive supporting member, and a nonconductive gap retaining member configured to retain a gap between the conductive supporting member and an image carrying member closely disposed to each other to have a constant distance. At least a portion of the nonconductive gap retaining member is mounted on the electrical resistance control layer at both ends of the conductive supporting member, and a circumference of the nonconductive gap retaining member projects from the electrical resistance control layer. An amount of projection of the gap retaining member from the electrical resistance control layer decreases as the gap retaining member tapers in a direction toward a center of an image formation region.
    Type: Application
    Filed: July 6, 2007
    Publication date: January 10, 2008
    Inventors: Masahiko Satoh, Masanori Kawasumi, Yoshiyuki Kimura, Eisaku Murakami, Hideki Zemba, Takeshi Uchitani, Shin Kayahara, Shunichi Hashimoto, Eiji Shimojo
  • Publication number: 20070281237
    Abstract: To provide an image forming apparatus, image forming method and process cartridge, which are excellent in low-temperature fixation properties, storage stability, durability and filming resistance, can reduce generation of odor, and are capable of forming an extremely high quality image. The apparatus includes: a latent electrostatic image bearing member; a charging unit; an exposing unit; a developing unit; a transferring unit; and a fixing unit; wherein the toner comprises a binder resin and coloring agent, and the binder resin comprises a polyester-based resin (A) and polyester-based resin (B) having a melting point at least 10° C. higher than that of the polyester-based resin (A), and at least one of the polyester-based resins (A) and (B) is a resin derived from a (meth)acrylic acid modified rosin and includes a polyester unit obtained by condensation polymerization of an alcohol component and a carboxylic acid component containing a (meth)acrylic acid modified rosin.
    Type: Application
    Filed: May 30, 2007
    Publication date: December 6, 2007
    Inventors: Yasuaki IWAMOTO, Yohichiroh Watanabe, Yasutada Shitara
  • Patent number: 7305194
    Abstract: Disclosed is an image forming method for an electrophotographic photoreceptor. The method provides for detecting a first streak in a first image; identifying the first streak location; shifting a charge device and marking a second image; identifying a second streak location; comparing the first streak location with the second streak location and determining a distance therebetween. The method further provides that on a first pass, charging a photoreceptor with the charge device; shifting the charge device from a first position to a second position along the photoreceptor corresponding to the distance; and, on a second pass, charging the photoreceptor with the charge device.
    Type: Grant
    Filed: June 24, 2005
    Date of Patent: December 4, 2007
    Assignee: Xerox Corporation
    Inventor: Bruce Thayer
  • Patent number: 7298993
    Abstract: Imaging methods, image engines, and photoconductor charging systems are described. According to one embodiment, an imaging method includes providing a charge device configured to provide an electrical charge to a surface of an imaging member which is usable for imaging, moving a surface of the charge device adjacent to the imaging member and a bias member, during the moving, first charging a discharged portion of the surface of the charge device using the bias member providing a charged portion of the surface of the charge device, during the moving, second charging a portion of the surface of the imaging member using the charged portion of the charge device, the second charging providing the discharged portion of the surface of the charge device, and repeating the first charging and the second charging during the moving.
    Type: Grant
    Filed: January 5, 2005
    Date of Patent: November 20, 2007
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Michael H. Lee, Boaz Tagansky, Omer Gila, William D. Holland, Seongsik Chang
  • Patent number: 7295788
    Abstract: An image forming apparatus includes an object to be charged whose surface moves. A charging device for charging the object uses an electrical discharge generated by applying a voltage including an alternating current component to a charging member provided in contact with or in proximity to the object. A latent image forming device forms an electrostatic latent image on the surface of the object. A developing device causes a two-component developer to come into contact with the image portion of the electrostatic latent image formed by the latent image forming device and affixes toner thereto. A protective substance is present on the surface of the object in the discharge region for charging the object, and the saturation magnetization of the carrier of the two-component developer with respect to an applied magnetic field of 1000 oersted is 40 to 80 emu/g.
    Type: Grant
    Filed: April 25, 2005
    Date of Patent: November 13, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroshi Nakai, Yasuo Suzuki, Nozomu Tamoto, Takahiko Tokumasu, Kazahiko Watanabe, Kohichi Ohshima, Noboru Tsukude, Nekka Matsuura, Hiroshi Ikuno
  • Patent number: 7289753
    Abstract: An image forming apparatus includes an image bearing member, and first and second chargers. Each of the chargers includes a magnetic member for generating magnetism, has a holding member for holding magnetic particles by a magnetic force, and charges the image bearing member by bringing the magnetic particles in contact therewith. The magnetic member of each of the chargers has a magnetic pole facing the image bearing member. The second charger is located at the tail end in the image bearing member rotational direction, but before a position at which an image is formed on the image bearing member. In the image bearing member rotation direction, and relative to a position at which the image bearing member comes closest to the holding member, the first charger's magnetic member has a peak magnetic force positioned downstream, and the second charger's magnetic member has a peak magnetic force positioned upstream.
    Type: Grant
    Filed: December 2, 2004
    Date of Patent: October 30, 2007
    Assignee: Canon Kabushiki Kaisha
    Inventor: Ryo Inoue
  • Publication number: 20070201895
    Abstract: The present invention relates to an electrophotographic photosensitive member including a substantially cylindrical body and a photosensitive layer formed on the outer circumference of the body. The body has an outer diameter larger at a middle portion of a latent image forming area than at end portions of the latent image forming area in the axial direction. The electrophotographic photosensitive member may further include a heating member accommodated within the body and extending along the axial direction of the body, for heating the latent image forming area of the photosensitive layer.
    Type: Application
    Filed: February 21, 2007
    Publication date: August 30, 2007
    Applicant: KYOCERA CORPORATION
    Inventor: Kouichi NAKANO
  • Patent number: 7251437
    Abstract: An image formation apparatus including at least a moving body to be charged, a charging device for charging the body to be charged using discharge caused by applying a voltage to a charging member provided in contact with or proximity to the body to be charged, a latent image formation device for forming a latent image on a surface of the body to be charged which is charged by the charging device, and a development device for depositing toner on an image portion of the latent image formed by the latent image formation device, wherein an elastic displacement ratio ?e for the surface of the body to be charged is equal to or greater than 40% which is defined by the following formula, elastic displacement ratio ?e (%)=[(maximum displacement)-(plastic displacement)]/(maximum displacement)×100, and the image formation apparatus further includes a protective material feeding device for depositing a protective material on at least a discharge area of the surface of the body to be charged.
    Type: Grant
    Filed: March 1, 2005
    Date of Patent: July 31, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Nozomu Tamoto, Tetsuro Suzuki, Yasuo Suzuki, Takahiko Tokumasu, Kazuhiko Watanabe, Hiroshi Nakai, Kohichi Ohshima, Noboru Tsukude, Nekka Matsuura
  • Publication number: 20070166076
    Abstract: The present invention provides a conductive member 10 with a superior durability by controlling an electric resistance value of an electric resistance adjusting layer 2 within a semi conductive range, preventing an ion conductive material from bleeding out of the electric resistance adjusting layer 2 to avoid improper charging and avoiding strength decreasing of a weld portion of the electric resistance adjusting layer and an electric resistance value fluctuation. The electric resistance adjusting layer 2 is made from a resin composition prepared by melting and kneading a thermoplastic resin, a high molecular ion conductive material containing an alkali metal salt and a graft copolymer which has an affinity for both the thermoplastic resin and the high molecular ion conductive material.
    Type: Application
    Filed: January 5, 2007
    Publication date: July 19, 2007
    Inventors: Tadayuki OSHIMA, Hiroki Furubayashi, Taisuke Tokuwaki, Tadaaki Hattori, Toshio Kojima, Makoto Nakamura, Yutaka Narita
  • Patent number: 7226551
    Abstract: It is an object of the present invention to provide a conductive member for use in OA equipment which shows very stable conductivity in the volume resistivity range of 105 to 1012 ?·cm, the conductivity of which is less dependent on the voltage applied and varies only slightly during continuous energization and upon changes in environmental factors such as temperature and humidity and which will not stain photoconductors due to bleeding or blooming. The present invention provides a conductive member for OA equipment, which is obtainable by molding a composition comprising a non-ether-based polyurethane and bis(trifluoromethanesulfonyl)imidolithium.
    Type: Grant
    Filed: April 22, 2002
    Date of Patent: June 5, 2007
    Assignee: Bando Chemical Industries, Ltd.
    Inventors: Takahiko Okazaki, Makoto Hasegawa, Takashi Miki, Takayuki Nagase, Hiroyuki Inai
  • Patent number: 7228091
    Abstract: In accordance with the invention, there is an electrophotographic charging device comprising a first electrode, a second electrode adjacent the first electrode, a plurality of nanotubes adhering to at least one of the first electrode and the second electrode, and a voltage supply electrically connected to the first electrode and the second electrode, wherein the first electrode and the second electrode impart charge to a portion of a gaseous material that is deposited on a receptor.
    Type: Grant
    Filed: June 10, 2005
    Date of Patent: June 5, 2007
    Assignee: Xerox Corporation
    Inventors: Dan A. Hays, Steven B. Bolte, Michael F. Zona, Joel A. Kubby
  • Patent number: 7215908
    Abstract: A method of operating an electrostatographic printing apparatus, the apparatus including a charge-retentive member defining an imaging surface and a charging device for placing a charge on the imaging surface, a gap existing between the imaging surface and the charging device, including applying an electrical bias to the charge-retentive member by generating a burst modulated waveform.
    Type: Grant
    Filed: March 30, 2005
    Date of Patent: May 8, 2007
    Assignee: Xerox Corporation
    Inventor: John S. Facci