Electric Charging Of Objects Or Materials Patents (Class 361/225)
  • Patent number: 5459558
    Abstract: A charging apparatus having a charging member contactable to a member to be charged, a pressing device for pressing the charging member onto the member to be charged at a pressing position. In the apparatus, an outside size of the charging member is larger away from the pressing position when the charging member is not pressed to the member to be charged.
    Type: Grant
    Filed: February 6, 1995
    Date of Patent: October 17, 1995
    Assignee: Canon Kabushiki Kaisha
    Inventor: Tatsunori Ishiyama
  • Patent number: 5457522
    Abstract: An image forming apparatus uses a contact-type charger to charge a photoreceptor. The D.C. current supplied to the charger is measured while the output value of the A.C. voltage is changed within a predetermined range, and the output value of the A.C. voltage is set in accordance with the measurement result.
    Type: Grant
    Filed: April 18, 1994
    Date of Patent: October 10, 1995
    Assignee: Konica Corporation
    Inventors: Satoshi Haneda, Kunio Shigeta, Sachie Hosogoezawa, Hiroyuki Nomori
  • Patent number: 5453819
    Abstract: A charger capable of reliably and uniformly maintaining a discharging gap formed in the vicinity of a contact portion between a charging member and a photosensitive member. A charging member 101 is arranged by supporting and fixing both ends of a flexible film 102 by means of support members 103 to 105. The film 102 forms a flexible portion oriented downwardly from fixed ends S1, S2. The film 102 is brought into contact with the member 110 to be charged in a state in which an unsupported side of the film 102 is oriented toward the downstream side in the rotating direction of the member 110 to be charged. Then, the film 102 is brought into contact with the member 110 to be charged in a contact area N, and the radius of curvature of the film 102 in a zone P2 located downstream of that zone N in the rotating direction of the member 110 to be charged becomes smaller than the radius of curvature of the film 102 in an upstream zone P1.
    Type: Grant
    Filed: March 17, 1994
    Date of Patent: September 26, 1995
    Assignee: Seiko Epson Corporation
    Inventors: Hidetsugu Shimura, Hajime Kurihara, Akihiko Ikegami, Takehiko Okamura, Takashi Hama, Kenjiro Yoshioka
  • Patent number: 5450171
    Abstract: Disclosed are a brush charger for preventing a rotary conductive brush, which contacts a latent image carrier to charge it, from bending along the rotary shaft of the conductive brush, and an image forming apparatus using this brush charger. The brush charger comprises a conductive rotary shaft; a conductive brush provided around the conductive rotary shaft in such a way that the tip of the conductive brush contacts the latent image carrier; a voltage source for applying a charging voltage to the conductive rotary shaft; elastic insulating members provided at both ends of the conductive rotary shaft, for restricting end portions of the conductive brush from spreading along the conductive rotary shaft; and stationary members respectively provided at one ends of the elastic insulating members, for compressing the elastic insulating members toward the conductive brush.
    Type: Grant
    Filed: August 10, 1993
    Date of Patent: September 12, 1995
    Assignee: Fujitsu Limited
    Inventors: Motohiro Demura, Makoto Matsuoka
  • Patent number: 5446615
    Abstract: An electrifying method which uses a electrifying a material wherein the contact-type electrifying member comprises a flexible and electrically conducting endless sheet and a brush which supports said endless sheet and imparts a pressing force thereto at a position where said endless sheet is in contact with the material to be electrified, said endless sheet which is impressed with an electrification voltage is driven or is moved at a speed which is substantially in synchronism with the material to be electrified, and the brush and the endless sheet are maintained at dissimilar speeds.
    Type: Grant
    Filed: March 26, 1993
    Date of Patent: August 29, 1995
    Assignee: Mita Industrial Co., Ltd.
    Inventors: Shoji Matsumoto, Masanori Matsuda, Eiji Goto, Akinori Nishida, Teruaki Higashiguchi, Isao Iwagawa
  • Patent number: 5436033
    Abstract: The invention concerns an ultra thin polymer film electret comprising a polymer and a substrate having a surface electric charge, wherein a side chain of the polymer and the substrate are physically or chemically bonded. A method of manufacturing an ultra thin polymer film electret comprising: adsorbing a monomolecular film comprising a unsaturated group or a laminated film comprising the monomolecular film on to a substrate surface, irradiating the monomolecular film or the laminated film with an energy beam to polymerize the unsaturated groups and applying a high voltage to the film is also disclosed. Further, a method of manufacturing an ultra thin polymer film electret comprising: physically bonding a side chain of the polymer to a substrate surface to form a thin film and applying a high voltage to the thin film is also disclosed.
    Type: Grant
    Filed: August 1, 1994
    Date of Patent: July 25, 1995
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Norihisa Mino, Yoshikazu Yamagata, Kazufumi Ogawa
  • Patent number: 5426557
    Abstract: An apparatus for treating the surfaces of formed plastic articles including a plurality of bare metal discharge electrodes connected to a high frequency AC power supply, a counterelectrode disposed in spaced relation to the discharge electrodes for defining a treatment zone therebetween, and an insulation layer mounted in spaced relation to the counterelectrode such that a discreet air space exists between the insulation and counterelectrode for moderating the electrical discharge between the discharge electrodes and counterelectrode and enabling greater control and uniformity in the electrical discharge between the electrodes and counterelectrodes.
    Type: Grant
    Filed: March 18, 1994
    Date of Patent: June 20, 1995
    Assignee: Trans Tech America
    Inventors: Mark Blitshteyn, Reinhard Gaenzle, Richard Wright
  • Patent number: 5426374
    Abstract: A piezoelectric body polarizing apparatus including a DC power supply 2 for applying a DC voltage to a piezoelectric body 1 to polarize the piezoelectric body 1, an impedance measuring circuit 4 for measuring the change in impedance of the piezoelectric body 1, a high frequency power supply 5, and a DC current blocking filter 3 connected between a high frequency portion, which is constituted by the impedance measuring circuit 4 and the high frequency power supply 5, and the piezoelectric body 1. The DC current blocking filter 3 includes at least a DC current blocking capacitor C.sub.1 and a transient current bypass capacitor C.sub.2 connected between a node A, between the DC current blocking capacitor C.sub.1 and the high frequency portion, and a ground potential.
    Type: Grant
    Filed: February 2, 1994
    Date of Patent: June 20, 1995
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Hideto Taka, Yoshikatsu Maeda
  • Patent number: 5426488
    Abstract: A charging member comprised of a conductive shaft and conductive fibers planted thereon is brought into contact with a charged member with a photoconductor provided on the surface thereof. The conductive shaft is applied with a combined voltage of d.c. voltage and a.c. voltage having a peak-peak value lower than two times the discharge starting threshold voltage that is determined by the surrounding atmosphere around the charged member. While the charging member and the charged member rotate at different surface velocity, the charged member is charged through the contact area in which impedance is low due to the influence of a.c. voltage, so that a stable surface potential close to the d.c. voltage may be charged onto the charged member. Further, it is effective that the frequency f of the a.c. voltage will be so set up as to suffice a relation: f>Vp/2R, where f is a frequency of the applied a.c. voltage, Vp(mm/s) is a moving velocity of the charged member, and R(mm) is a particle size of a developer used.
    Type: Grant
    Filed: October 14, 1993
    Date of Patent: June 20, 1995
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Takashi Hayakawa, Kenji Tani, Katsumi Adachi
  • Patent number: 5426489
    Abstract: An image forming apparatus such as an electrophotographic copier and an electrophotographic printer. The image forming apparatus includes: a photoreceptor for forming a toner image on its surface; a charger for charging the surface with a bias voltage, including a DC component and a AC component, through a magnetic brush member which is in contact with the surface; a driving unit for moving both of the surface of the photoreceptor and the magnetic brush member in synchronism; a laser unit for imagewisely exposing a predetermined image area of the surface, which is charged by the charger, so that a latent image is formed on the surface; and a discharge lamp for exposing the surface with light so that the surface is discharged.
    Type: Grant
    Filed: March 22, 1994
    Date of Patent: June 20, 1995
    Assignee: Konica Corporation
    Inventors: Satoshi Haneda, Kunio Shigeta, Sachie Hosogoezawa, Hiroyuki Nomori, Masakazu Fukuchi
  • Patent number: 5420677
    Abstract: A method and apparatus for extending the electrical life of a bias transfer roll is disclosed. The apparatus includes a biasing member comprising a bias roll member or other charging device for reversing current flow through the bias transfer roll. The apparatus of the present invention permits reversal of current flow through a bias transfer roll to replenish ions depleted therefrom during the transfer process.
    Type: Grant
    Filed: November 8, 1991
    Date of Patent: May 30, 1995
    Assignee: Xerox Corporation
    Inventors: Robert A. Gross, Kenneth W. Pietrowski
  • Patent number: 5418680
    Abstract: An apparatus for repairing a defective semiconductor device having an electrically short-circuited portion, wherein the semiconductor device includes a semiconductor thin film and a conductive thin film disposed in the named order on a conductive surface of a substrate and in which the conductive thin film and the conductive surface of the substrate are electrically short-circuited at a pinhole occurring in the semiconductor thin film to form an electrically short-circuited portion so that the semiconductor device is defective. The apparatus includes a substrate holding unit for holding the substrate of the defective semiconductor device and an electrode arranged above the substrate holding unit so that, when the defective semiconductor is positioned on the substrate holding unit, there is a predetermined distance between the electrode and the conductive thin film of the defective semiconductor device, the electrode being capable of moving in relation to the substrate of the defective semiconductor device.
    Type: Grant
    Filed: November 22, 1993
    Date of Patent: May 23, 1995
    Assignee: Canon Kabushiki Kaisha
    Inventors: Keishi Saito, Tatsuyuki Aoike, Mitsuyuki Niwa, Toshimitsu Kariya, Yuzo Koda
  • Patent number: 5418605
    Abstract: A charging device includes a member to be charged, and a charging member for charging the member to be charged. The charging member includes a surface layer which can contact the surface of the member to be charged. A voltage is applied between the member to be charged and the charging member. The contact angle with water .gamma..sub.R of the surface layer of the charging member is greater than the contact angle with water .gamma..sub.D of the surface of the member to be charged. An image forming apparatus includes the above-described charging device.
    Type: Grant
    Filed: November 22, 1993
    Date of Patent: May 23, 1995
    Assignee: Canon Kabushiki Kaisha
    Inventors: Fumihiro Arahira, Tsuyoshi Watanabe, Takao Honda, Makoto Yanagida
  • Patent number: 5406353
    Abstract: An electrophotographic printer is disclosed with the printer having a cylindrical, electrostatic latent image-bearing member, a non-corona-discharge electric charging device, an electrostatic latent image former, a developer, a device for transferring the developed image onto a recording medium, a cleaner for cleaning the surface of the latent image-bearing member, and a fixing device located downstream of the latent image bearing member for heat fixing a developed image onto the recording medium. The charging device is provided by a permanently magnetized charging roll and magnetic powder having an intrinsic volume resistance of 10.sup.2 -10 .OMEGA..cm. The magnetic powder is attracted onto the charging roll forming a magnetic brush without an externally applied bias voltage on the surface of the charging roll.
    Type: Grant
    Filed: June 24, 1993
    Date of Patent: April 11, 1995
    Assignee: Hitachi Metals, Ltd.
    Inventor: Masumi Asanae
  • Patent number: 5402213
    Abstract: A contact charging device for charging an outer surface of an electrostatic latent image carrier in contact therewith which has a charging member at least partly in contact with the electrostatic latent image carrier, the portion of the charging member in contact with the electrostatic latent image carrier being formed by a layer containing a copolymer of an olefin-type vinyl monomer and a fluorine-contained monomer, and a power supply for applying a charging voltage to the charging member.
    Type: Grant
    Filed: November 12, 1993
    Date of Patent: March 28, 1995
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventors: Akihito Ikegawa, Masaki Asano, Keiko Nagayasu, Masashi Yamamoto
  • Patent number: 5401446
    Abstract: Method and apparatus for electrostatically charging a web or film by subjecting the web or film to an electric field generated between a single bar or wire electrode and the curved surface of a second electrode, and optionally sequentially subjecting the web or film to subsequent electric fields preferably in which the polarity of the field, relative to the web or film, is reversed.
    Type: Grant
    Filed: October 9, 1992
    Date of Patent: March 28, 1995
    Assignee: The University of Tennessee Research Corporation
    Inventors: Peter P. Tsai, Larry C. Wadsworth
  • Patent number: 5398102
    Abstract: The invention is directed to an apparatus for an electrophotographic process, equipped with a charging device of a contact type using a conductive roller or brush, and the charging device used therefor.
    Type: Grant
    Filed: April 21, 1993
    Date of Patent: March 14, 1995
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Takasumi Wada, Kenji Tani, Takashi Hayakawa, Kouichi Irihara, Yukihito Nishio
  • Patent number: 5394221
    Abstract: An image forming apparatus includes a microcomputer. The number of image forming operation of a photosensitive drum is counted by a counter as a copy quantity, and data of the copy quantity is applied to the microcomputer. By referring to a copy quantity-voltage table, voltage setting data according to the copy quantity is applied by the microcomputer to a bias voltage source so that the bias voltage source applies a required bias voltage according to the voltage setting data to a conductive substrate of the photosensitive drum.
    Type: Grant
    Filed: June 14, 1993
    Date of Patent: February 28, 1995
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Yasuhiro Kishimoto, Naoyuki Hashimoto, Hitoshi Hattori
  • Patent number: 5390007
    Abstract: A charging member contactable to a member to be charged to electrically charge it includes a sponge layer; a coating layer disposed between the sponge layer and the member to be charged; wherein a cell diameter in a surface of the sponge layer coated with the coating layer is not more than 200 microns.
    Type: Grant
    Filed: February 16, 1993
    Date of Patent: February 14, 1995
    Assignee: Canon Kabushiki Kaisha
    Inventors: Harumi Kugoh, Junji Araya, Hideyuki Yano
  • Patent number: 5384626
    Abstract: A charging member for charging a member to be charged while being in contact therewith includes conductive base for being supplied with a voltage; a surface layer contactable to the member to be charged; a sponge layer between the conductive base and the surface layer; a 100% modulus M.sub.100 (kg/cm.sup.2) of the surface layer and a thickness d (cm) of the surface layer satisfied:M.sub.100 .times.d.ltoreq.1.5 (kg/cm).
    Type: Grant
    Filed: September 7, 1993
    Date of Patent: January 24, 1995
    Assignee: Canon Kabushiki Kaisha
    Inventors: Harumi Kugoh, Junji Araya, Hideyuki Yano, Tadashi Furuya
  • Patent number: 5381215
    Abstract: A device for charging a photoreceptor on which a toner image is formed, comprises a rotatable sleeve, at least two magnets disposed in the sleeve so as to attract magnetic particles in a form of magnetic brush, and a electric power source to provide the photoreceptor with an electric charge through the magnetic brush. One of the magnets is disposed upstream of the closest point between the photoreceptor and the sleeve, and the other magnet is disposed downstream of the closest point.
    Type: Grant
    Filed: October 12, 1993
    Date of Patent: January 10, 1995
    Assignee: Konica Corporation
    Inventors: Satoshi Haneda, Kunio Shigeta, Sachie Hosokoezawa, Masakazu Fukuchi, Shizuo Morita, Hiroyuki Nomori
  • Patent number: 5376425
    Abstract: A contact member for controlling an electrostatic state of a surface of a chargeable member includes electrically conductive base members, and flame retardant material included in the base members.
    Type: Grant
    Filed: December 17, 1992
    Date of Patent: December 27, 1994
    Assignees: Minolta Camera Kabushiki Kaisha, Toeisangyo Co., Ltd.
    Inventors: Masaki Asano, Shuji Iino, Akihito Ikegawa, Izumi Osawa, Kenzo Tanaka
  • Patent number: 5376995
    Abstract: A contact charger in an electrophotographic image forming apparatus for electrostatically charging a photosensitive, latent image support surface of a rotatably supported photosensitive drum in contact therewith. The contact charger comprises a generally elongated carrier and a charging member carried at a first side edge by the carrier. This charging member has a second side edge opposite to the first side edge which is held in sliding contact with the photosensitive surface over a predetermined contact distance. The charging member has a curved surface of a radius of curvature of 0.02 to 1.0 mm at a side edge portion thereof at which contact of the charging member with the photosensitive surface terminates. A power source for applying a voltage to the charging member is also employed.
    Type: Grant
    Filed: October 25, 1993
    Date of Patent: December 27, 1994
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventors: Masashi Yamamoto, Masaki Asano, Keiko Nagayasu, Akihito Ikegawa
  • Patent number: 5374979
    Abstract: An image forming apparatus having both an image data carrying member for carrying and forwarding image data rendered into a visible image by a developer and a device requiring high voltage in the form of a unit separable from a body of the image forming apparatus, wherein, inside the separable unit are a high voltage generator for the device and an electrically conductive member, the high voltage generator being disposed within the image data carrying member, the electrically conductive member being interposed between the image data carrying member and the high voltage generator and between the device and the high voltage generator, insulating members being interposed between the electrically conductive member and the image data carrying member and between the electrically conductive member and the device, the electrically conductive member being grounded.
    Type: Grant
    Filed: March 1, 1994
    Date of Patent: December 20, 1994
    Assignee: Fuji Xerox Co., Ltd.
    Inventor: Mikio Kobayashi
  • Patent number: 5371649
    Abstract: In a method of corona discharge processing of resin formings surface, excellent corona discharge processing is possible, even if there is a distance between the resin formings and the discharge electrode, by generating a high voltage pulse having a pulse width of 1 .mu.s or more, an average electric field strength of 4 to 20 kv/cm denoted by applied voltage (wave height) versus interelectrode distance, and a pulse frequency of 10 pps or more. This processing is performed by the apparatus which comprises arranging a transfer conveyor to transfer the resin formings, a counter-electrode placed in a down side of the transfer conveyor, a dielectric to cover a surface of the counter-electrode, and a number of discharge electrodes which are arranged in a definite distance above the resin formings along the transfer route.
    Type: Grant
    Filed: June 7, 1993
    Date of Patent: December 6, 1994
    Assignees: Nippon Paint Co., Ltd., Mazda Motor Corporation
    Inventors: Akinori Iwata, Makoto Moriyama, Kouichi Kuwano, Kensuke Akutsu, Koji Ueki, Ikuo Tochizawa, Hirohiko Koge, Takanori Hara, Yuji Tanaka, Masatoshi Fujii
  • Patent number: 5367365
    Abstract: An image forming machine has a charging roller on which magnetic particles are supplied to form a magnetic brush and an image forming body which is charged under the condition that the magnetic brush on the charging roller is in an alternating electric field. When the distance between a regulating member that regulates an amount of the magnetic particles passing through and the charging roller is defined to be DB and the distance between the image forming body and the charging roller is defined to be DI, an inequality of 0.7 DB.ltoreq.DI.ltoreq.1.0 DB is satisfied. More preferably, DB is in the relation of 0.2.ltoreq.DB.ltoreq.1.0 in mm.
    Type: Grant
    Filed: October 12, 1993
    Date of Patent: November 22, 1994
    Assignee: Konica Corporation
    Inventors: Satoshi Haneda, Kunio Shigeta, Sachie Hosokoezawa, Masakazu Fukuchi, Shizuo Morita, Hiroyuki Nomori
  • Patent number: 5363176
    Abstract: A charger having a surface layer, the content of components of the surface layer having a molecular weight of 1,000 or less in a resin is 0.5 wt % or less, charges a member to be charged by contacting the member to be charged in an electrophotographic apparatus or the like.
    Type: Grant
    Filed: January 26, 1994
    Date of Patent: November 8, 1994
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yuzi Ishihara, Hisayo Ito
  • Patent number: 5359395
    Abstract: A contact charge supply device for externally controlling the charges, which are supplied to a member to be charged by bringing a contact member appled with an external voltage into contact with the member to be charged, which at least includes an underlayer, and holds the following inequalitylog (R).gtoreq.log {Rp.times.(Va-Vt)/Vt}+(.alpha.-.beta.).times.log(S/s)+.gamma..times.log (i/I)where .vertline.Va.vertline..gtoreq..vertline.Vt.vertline.,Va (V): voltage applied to a contact member in contact with the member to be charged; I (.mu.A): current flowing from the contact member to the member to be charged; S (cm.sup.2): contact area of the member to be charged and the contact member; R (.OMEGA.): resistance of the contact member when current I (.mu.A) is fed to an area corresponding to the contact area S (cm.sup.2) of the contact member; .gamma.: current dependency of the resistance of the contact member; 1-.beta.: area dependency of the resistance of the contact member; s (cm.sup.
    Type: Grant
    Filed: November 5, 1993
    Date of Patent: October 25, 1994
    Assignee: Seiko Epson Corporation
    Inventors: Hidetsugu Shimura, Hajime Kurihara, Akihiko Ikegami, Hiroshi Tanaka, Kenjirou Yoshioka
  • Patent number: 5359393
    Abstract: A photoreceptor charging device, already provided in an electrophotographic printing machine, is used to determine the voltage potential of a portion of the photoreceptor located adjacent to the photoreceptor charging device. In particular, an operating condition of the photoreceptor charging device, such as, for example, the total current supplied to a coronode and to a grid of the photoreceptor charging device, or the voltage potential of the grid of the photoreceptor charging device when the total current is a predetermined, relatively small value, is used to determine the voltage potential of the photoreceptor adjacent to the charging device.
    Type: Grant
    Filed: December 22, 1992
    Date of Patent: October 25, 1994
    Assignee: Xerox Corporation
    Inventor: Jeffrey J. Folkins
  • Patent number: 5357323
    Abstract: An image forming machine such as a copier or a printer for developing a latent image on a photoreceptor with toner. The image forming machine includes a sleeve for charging the photoreceptor; magnetic particles for forming a magnetic brush on a surface of the sleeve; a driver for driving the sleeve so that the magnetic brush is moved; and a power applying circuit for applying an alternating current between 20 and 500 .mu.A/cm on to a charging area between the sleeve and the photoreceptor; in which the sleeve is located in the vicinity of the photoreceptor so that the magnetic brush is in contact with the surface of the photoreceptor.
    Type: Grant
    Filed: October 15, 1993
    Date of Patent: October 18, 1994
    Assignee: Konica Corporation
    Inventors: Satoshi Haneda, Kunio Shigeta, Sachie Hosokoezawa, Masakazu Fukuchi, Shizuo Morita, Hiroyuki Nomori
  • Patent number: 5357322
    Abstract: A charging device for charging a moving member to be charged includes a charging member for contact with the member to be charged to which a voltage is applied; wherein the charging member has a volume resistivity of not more than 1.times.10.sup.9 ohm.cm, and a surface resistivity at a surface contactable to the member to be charged not less than 5.times.10 ohm/.quadrature..
    Type: Grant
    Filed: December 28, 1992
    Date of Patent: October 18, 1994
    Assignee: Canon Kabushiki Kaisha
    Inventor: Norihisa Hoshika
  • Patent number: 5354489
    Abstract: A homogeneous electrorheological fluid is disclosed, which mainly comprises a liquid crystal compound in which a plurality of liquid crystal groups are bonded to a molecular chain either directly or via a spacer, or comprises a lyotropic liquid crystal comprising a solute and a solvent. The electrorheological fluid exhibits higher electrorheological effects as well as high response rate and low power driving properties while being free from sedimentation or flocculation.
    Type: Grant
    Filed: August 28, 1991
    Date of Patent: October 11, 1994
    Assignee: Asahi Kasei Kogyo Kabushiki Kaisha
    Inventors: Akio Inoue, Syunji Maniwa
  • Patent number: 5353101
    Abstract: A charging member for charging a member to be charged includes a blade member having an electrode layer and/or a resistive layer thereon, and a supporting member for supporting the blade member. The blade member is cut into a predetermined size together with the electrode layer and/or the resistive layer after forming the electrode layer and/or the resistive layer. A charging device uses the charging member. A process unit including the charging device is detachable relative to an image forming apparatus.
    Type: Grant
    Filed: January 23, 1991
    Date of Patent: October 4, 1994
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hiroyuki Adachi, Norihisa Hoshika
  • Patent number: 5351111
    Abstract: A corona discharge device includes a corona discharge electrode, and a control electrode interposed between the corona discharge electrode and a target object to be corona discharged for controlling a surface potential of the target object. The control electrode includes a film coating processed portion with a conductive dry film coating and an unprocessed portion with no film coating formed in at least one of two end portions of the control electrode in a longitudinal direction of the control electrode. The unprocessed portion of the control electrode has an opening ratio smaller than that of the film coating processed portion.
    Type: Grant
    Filed: October 29, 1993
    Date of Patent: September 27, 1994
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Akihiro Takafuji, Osamu Shimizu
  • Patent number: 5351109
    Abstract: Apparatus for charging an imaging surface of a photoreceptor. The apparatus forms a magnetic brush on a cylinder spaced apart from and facing the photoreceptor by a magnet disposed in the cylinder. The cylinder and the magnet are rotatable relative to each other so that the magnetic brush moves around the cylinder and comes in contact with the imaging surface of the photoreceptor. An electric bias source is provided to apply an electric bias voltage having a DC voltage component and an AC voltage component between the imaging surface of the photoreceptor and the cylinder, whereby the imaging surface is charged by the magnetic brush under the electric bias voltage.
    Type: Grant
    Filed: November 16, 1992
    Date of Patent: September 27, 1994
    Assignee: Konica Corporation
    Inventor: Satoshi Haneda
  • Patent number: 5345299
    Abstract: An image-forming machine equipped with a transfer device means of the type not using a transfer corona discharger is disclosed. A charge supply member is disposed opposite to an image forming member on whose surface a toner image is to be formed and at a greater distance than the thickness of a transfer material from the image forming member. In a transfer zone, the surface of the transfer material is brought into contact with the surface of the image forming member. In a charge supply zone, the transfer material is contacted with the surface of the charge supply member. In the direction of conveyance of the transfer material, the charge supply zone is positioned downstream of the transfer zone.
    Type: Grant
    Filed: September 14, 1993
    Date of Patent: September 6, 1994
    Assignee: Mita Industrial Co., Ltd.
    Inventors: Masahiro Hashizume, Hiroshi Kimura, Hiroshi Ishida, Masanobu Maeshima, Koichi Yasuda, Shigeki Hayashi, Hiroshi Kubota, Osamu Yoshimura, Susumu Taniguchi, Yasuo Hatate
  • Patent number: 5335050
    Abstract: An adjustable support assembly for adjustably supporting a corona generating device at a selected distance from a photoreceptive surface, wherein a fixedly mounted support bracket and an adjustable support bracket are mounted in a cooperatively nested relationship such that reciprocating movement can be affected between the adjustable support bracket and the fixedly mounted support bracket. The adjustable support assembly is provided with support blocks for adjusting the gap between the corona generating device and the photoreceptive surface from a single general location.
    Type: Grant
    Filed: September 13, 1993
    Date of Patent: August 2, 1994
    Assignee: Xerox Corporation
    Inventors: William G. Osbourne, Julio A. Sanchez-Banos
  • Patent number: 5335053
    Abstract: The present invention provides an image forming apparatus with a recording sheet bearing member for bearing a recording sheet on which an image is to be formed, a charger brush contacting with a surface of the recording sheet bearing member opposite to a surface thereof on which the recording sheet is carried, and adapted to apply charge to the carrying member, and a grounded conductive member arranged out of a range of movement of a tip of the charger brush.
    Type: Grant
    Filed: March 17, 1993
    Date of Patent: August 2, 1994
    Assignee: Canon Kabushiki Kaisha
    Inventor: Takashi Hasegawa
  • Patent number: 5321472
    Abstract: A charging member for charging a body to be charged includes a blade member, a supporting member which supports the blade member, and an electrode layer which is provided on the blade member and is connected to the supporting member. The electrode layer is formed after connecting the blade member to the supporting member. A charging device uses the charging member. A process unit including the charging device is detachable relative to an image forming apparatus.
    Type: Grant
    Filed: June 17, 1993
    Date of Patent: June 14, 1994
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hiroyuki Adachi, Norihisa Hoshika
  • Patent number: 5313359
    Abstract: A contact charger includes a photoreceptor having a photosensitive layer formed on a surface of an electrically conductive drum base and a fixed coil connected to the drum base and ground. The contact charger charges the photosensitive layer by making a charge roller in contact with the photosensitive layer while being applied thereto DC voltage from a power supply. With this arrangement, in the case where a pin hole exists on the photosensitive layer, there may have a continuity between the charge roller and the drum base which may results in a sudden increase in current flowing between the drum base and ground. When this happens, however, since self-induced electromotive force, having a direction opposite to the electromotive force of the power supply, is generated by the fixed coil in response to a sudden increase in current, excessive current will not flow between the drum base and ground, thereby eliminating the possibility of a large drop in voltage of the power supply.
    Type: Grant
    Filed: May 29, 1992
    Date of Patent: May 17, 1994
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Shinji Imagawa, Koichi Inui
  • Patent number: 5309207
    Abstract: The picture image forming apparatus of a type which performs a light exposing on an image holding surface charged at a constant voltage by a charging device having a grid electrode to form an electrostatic latent image and then supplies a toner from a developing device to change the latent image into a visible image, including a voltage division and adjustment circuit for dividing a voltage applied to the grid electrode of the charging device and for adjusting the divided voltage to a predetermined bias voltage for the developing device, a modification and drive circuit for absorbing and modifying a fluctuation of the bias voltage which has been divided and adjusted by the division and adjustment circuit and for driving the division and adjustment circuit, and an operating circuit for operating the drive circuit.
    Type: Grant
    Filed: June 15, 1992
    Date of Patent: May 3, 1994
    Assignee: Murata Kikai Kabushiki Kaisha
    Inventor: Takashi Omori
  • Patent number: 5305177
    Abstract: A charging device includes a charging member contactable to a member to be charged. A bias source includes an AC source and a DC source and is effective to apply a bias voltage to the charging member. The bias voltage is provided by a superposing a constant current controlled AC voltage and a constant voltage controlled DC voltage. When a DC voltage is applied between the charging member and the member to be charged, the following equation is satisfied..vertline.(applied voltage V)-(charge voltage V.sub.D of the member to be charged).vertline.=.vertline.(charge starting voltage V.sub.TH).vertline..The charge starting voltage is a DC voltage at a level which the member to be charged starts charging when only a DC voltage is applied between the member to be charged and the charging member. When the above relationship is used in the AC voltage application, the charge voltage V.sub.D oscillates in the charge region with a center of DC voltage V.sub.DC.
    Type: Grant
    Filed: November 1, 1991
    Date of Patent: April 19, 1994
    Assignee: Canon Kabushiki Kaisha
    Inventors: Fumitaka Aoki, Yasushi Sato, Norio Hashimoto, Tetsuo Saito, Hirokazu Ikenoue, Kenji Nagata, Toshihiko Yamanaka
  • Patent number: 5295039
    Abstract: A charging apparatus for applying single polar electrostatic charges to a surface of a continuously travelling long web support before coating the support with a coating composition comprises a fine wire shaped corona discharging electrode connected to a electric source and a pass roller coated by a coating, the pass roller facing said corona discharging through the support.
    Type: Grant
    Filed: November 3, 1992
    Date of Patent: March 15, 1994
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Kenji Nakajima, Atsuo Futami
  • Patent number: 5294962
    Abstract: An image forming apparatus includes an image carrier which is rotated in a predetermined direction, a brush charger which charges a surface of the carrier, an exposure unit which forms an electrostatic latent image on the charged surface of the carrier in accordance with image information supplied thereto, a developer which develops the electrostatic latent image with a toner, and a transfer unit which transfers a toner image from the surface of the carrier onto a transfer medium supplied thereto. The image carrier includes a conductive main body, an undercoat having a predetermined electric resistance higher than that of the main body, and a photosensitive layer, which is formed on the undercoat, and on which an electrostatic latent image is formed by the exposure unit after charging is performed by the charger. The charger includes a main body constituted by bristles consisting of conductive fibers having electric resistance within the range from about 10.sup.6 to about 10.sup.9 .OMEGA.
    Type: Grant
    Filed: November 5, 1992
    Date of Patent: March 15, 1994
    Assignees: Casio Electronics Manufacturing Co., Ltd., Casio Computer Co., Ltd.
    Inventors: Masaru Sato, Tetsuya Abe
  • Patent number: 5293200
    Abstract: In an electrostatic device that uses a resistance film for electrifying a latent image holder in printing devices, such as a photo-copier or a facsimile, at least one electrode borders the resistance film. The electrostatic device confronts a latent image holder, having a cylindrical shape, across a narrow gap and along the length of the latent image holder. With this structure, applying D.C. voltage to the electrode electrifies the latent image holder via the resistance film. Since the resistance film and the electrode overlap each other, the potential on the latent image holder is dependent on the surface resistance rather than the volume resistance of the resistance film giving the electrostatic device an immunity from nonuniformity or flaws in the surface of the resistance film. In addition, an electrostatic device of this invention has a structural advantage over conventional scorotron devices.
    Type: Grant
    Filed: December 29, 1992
    Date of Patent: March 8, 1994
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventor: Shusaku Tsusaka
  • Patent number: 5289234
    Abstract: An image forming apparatus having a detachable imaging cartridge which includes a photosensitive member charged by a charge brush having brush fibers. At least one of the photosensitive member and the charging brush is detachable from the imaging cartridge, and the detachable one is attached to the imaging cartridge through a guide member so that the brush fibers of the charge brush are indented toward a downstream side relative to a predetermined position of the charge brush with respect to the rotational direction of the photosensitive member.
    Type: Grant
    Filed: July 22, 1993
    Date of Patent: February 22, 1994
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventors: Masaki Asano, Shuji Iino, Akihito Ikegawa, Izumi Osawa
  • Patent number: 5287152
    Abstract: An electric charge supplying device for supplying electric charges to a body to be charged, comprises a charge-supplying member arranged in contact with the body to be charged, a power supply for supplying electricity to the charge-supplying member, and a shunt resistance connected in parallel with a series circuit including the charge supplying member and the body to be charged, the shunt resistance having environmental dependency of resistance substantially equal to that of the charge supplying member.
    Type: Grant
    Filed: December 15, 1992
    Date of Patent: February 15, 1994
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventors: Tateki Oka, Kazuyoshi Hara, Koji Uno, Hitoshi Saito, Yasuo Tanaka
  • Patent number: 5287146
    Abstract: A contact type charging device having a contact member for making contact with the surface of a charge bearing member so as to apply an electric charge to the surface in an image forming apparatus of the electrophotographic type, and having a charging device which has a high resistance resistor connected serially to the contact member so as to apply a voltage to the contact member. The contact type charging device has a regulating member for regulating the upper limit of the absolute value of the voltage applied to the contact member to prevent excessive current flow to the contact member, or has a regulating member for regulating the lower limit of the absolute value of the voltage applied to the contact member to prevent a greater than necessary drop of the voltage applied to the charge bearing member.
    Type: Grant
    Filed: June 30, 1992
    Date of Patent: February 15, 1994
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventors: Koji Uno, Yasuo Tanaka, Tateki Oka, Hitoshi Saito
  • Patent number: 5280406
    Abstract: A process for depositing electrical charges on a dielectric surface by means of a high velocity jet of fluid which strikes the surface, flows over it and triboelectrically charges it, and then separates from the surface.
    Type: Grant
    Filed: June 18, 1992
    Date of Patent: January 18, 1994
    Assignee: International Business Machines Corporation
    Inventors: Hans J. Coufal, Robert K. Grygier
  • Patent number: 5278614
    Abstract: A contact charger for charging an image bearing member includes a support member, a flexible film supported by the support member and having a free end adapted to contact the surface of the image bearing member, and a power device for applying a charging voltage to the flexible film wherein the flexible film has an electrically conductive substrate layer and an electrically insulated overcoat layer superposed onto the substrate layer.
    Type: Grant
    Filed: April 15, 1993
    Date of Patent: January 11, 1994
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventors: Akihito Ikegawa, Masaki Asano, Shuji Iino, Izumi Osawa