US3743830A - Device for uniformly charging a non-planar electrophotographic plate - Google Patents

Device for uniformly charging a non-planar electrophotographic plate Download PDF

Info

Publication number
US3743830A
US3743830A US00224990A US3743830DA US3743830A US 3743830 A US3743830 A US 3743830A US 00224990 A US00224990 A US 00224990A US 3743830D A US3743830D A US 3743830DA US 3743830 A US3743830 A US 3743830A
Authority
US
United States
Prior art keywords
follower
planar member
discharge electrode
plate
charging
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US00224990A
Other languages
English (en)
Inventor
I Takahashi
M Sato
S Honjo
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Xerox Corp
Original Assignee
Xerox Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Xerox Corp filed Critical Xerox Corp
Application granted granted Critical
Publication of US3743830A publication Critical patent/US3743830A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01T—SPARK GAPS; OVERVOLTAGE ARRESTERS USING SPARK GAPS; SPARKING PLUGS; CORONA DEVICES; GENERATING IONS TO BE INTRODUCED INTO NON-ENCLOSED GASES
    • H01T19/00—Devices providing for corona discharge
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00—Apparatus for electrographic processes using a charge pattern
    • G03G15/02—Apparatus for electrographic processes using a charge pattern for laying down a uniform charge, e.g. for sensitising; Corona discharge devices
    • G03G15/0291—Apparatus for electrographic processes using a charge pattern for laying down a uniform charge, e.g. for sensitising; Corona discharge devices corona discharge devices, e.g. wires, pointed electrodes, means for cleaning the corona discharge device

Definitions

  • the follower member and discharge electrode are arranged to uniformly deposit charge on a selected portion of the insulating member.
  • Electrostatically charging a photoconductive insulating layer on a conductive support having an irregularly shaped or curved surface with any of the conventional corona charging devices results in uneven distribution of charge in which the raised area of the curved surface accepts a higher potential while the depressed area are charged to a lesser potential, since the spacing between the corona discharge electrode and the layer surface varies from location to location.
  • image exposure and subsequent development are carried out onto such an unevenly charged layer, an acceptable quality image is not produced. It is therefore necessary to produce uniform charging of the layer throughout the area on which the image is to be formed.
  • the present invention provides apparatus for charging the entire surface or predetermined portions of the surface of an insulating member, the surface of the member being irregularly shaped.
  • a corona discharge electrode is maintained at a predetermined distance above the surface of the member and at a constant distance from a follower member, the follower member being maintained in contact with the non-charging surface of the member.
  • the discharge electrode is energized, a substantially uniform charge is produced on the surface of the insulating member.
  • FIG. 1 is a schematic cross-sectional view of charging apparatus in accordance with the present invention.
  • FIG. 2 is a perspective view of one embodiment of the present invention.
  • FIG. 3 is another embodiment of the present invention.
  • FIG. 4 is a cross-sectional view of the embodiment I shown in FIG. 3 at the plane IV-IV in FIG. 3;
  • FIG. 5 shows a cross-sectional view of still another embodiment of the present invention.
  • FIG. 1 one embodiment of charging apparatus of the present invention is shown.
  • the apparatus uniformly charges a plate 13 comprising electrophotographic, or photoconductive layer 12 formed on curved conductive substrate 11 of a substantially uniform thickness.
  • Typical electrophotographic materials include cadmium sulfide, selenium, zinc oxide, sulphur selenium, etc.
  • a follower 14 is utilized which is of a structure that enables it to smoothly move along the rear, or non-charging, surface of substrate 11.
  • a corona discharge electrode 15 At a predetermined distance from follower 14 and above the front surface of the plate 13 is provided a corona discharge electrode 15, with which the follower 14 is connected by suitable mechanical, magnetic or electromagnetic means as shown by a broken line 16 so as to keep a constant distance therebetween.
  • the curved plate or recording member 13 is inserted between corona discharge electrode 15 and follower 14. With the follower kept in contact with the rear surface of the substrate 11, the recording member 13 is moved in the direction of arrow 17 by a driving means (not shown). It should be noted that the recording member 13 may be maintained stationary and the follower 14 moved relative thereto. When a high potential is applied to corona discharge electrode 15, the electrophotographic layer 12 is substantially uniformly charged, since the distance between the discharge electrode l5 and the layer 12 beneath the electrode is always kept constant by virtue of the presence of follower 14. This distance is equal to that between the top of the follower and the tip of the discharge electrode minus the thickness of the plate member 13.
  • the predetermined distance between discharge electrode 15 and follower 14 may be selected to be shorter than the minimum radius of ourvature in the plate member to be charged.
  • the corona discharge electrode 15 may be made of one or more parallelly oriented wires as shown in FIG. 2 or a row of pin electrodes.
  • the follower 14 may be a long cylinder as shown in FIG. 2, an array of short cylinders or an array of multiple balls extending in the direction along which the member is linear flat.
  • the follower 14 preferably comprises a single ball as will be described hereinafter with reference'to FIG. 3.
  • the ball or cylinder preferably has a radius not larger than the minimum radius of curvature in the configuration of the member to be charged.
  • the follower 14 should rotate smoothly and freely around its axis or center in order to accomplish a smooth movement along the rear surface of the plate member.
  • FIG. 2 illustrates one embodiment of the present invention suitable for charging an electrophotographic member, such as corrugated plate 21, which is linear in one direction.
  • the apparatus comprises a charging unit and a cylindrical follower 24, the former comprising a wire electrode 23 mounted in a grounded shield 22.
  • the shield 22 in the embodiment illustrated has a generally inverted U-shaped cross-section.
  • the follower 24 has a radius smaller than the minimum radius of curvature of the electrophotographic member 21 and is setup rotatably and in the horizontal plane.
  • the electrode 23 and the follower 24 are linked with a pair of connecting members 25 and the wire 23 is maintained parallel both to the cylinder 24 and to the surface of member 21 with a spacing suitable for corona charging.
  • the spacing may be selected to be less than the minimum radius of curvature of the member 21.
  • the members 25 have a structure capable of adjusting the distance between wire electrode 23 and follower 24, and are held by main supports 27 through springs 26 which keep the cylinder 24 in contact with the electrophotographic member 21, exerting a recovery force in the direction shown by the arrow 28 against a force downwardly applied to the follower 24 by member 21.
  • the member is inserted between the follower 24 and the wire electrode 23 with the electrophotographic layer up in such a manner that the follower 24 is in contact with the highest portion of he member with the springs being ultimately contracted or compressed.
  • a support 29 is used to set the member 21 in a horizontal position.
  • the member 21 is then driven in the direction shown by arrow 30 by a driving means (not shown) at a constant speed with a high electrical potential applied to the wire electrode 23, whereby the corona discharge generated at wire electrode 23 impinges the electrophotographic layer on member 21.
  • a driving means not shown
  • member 21 suppresses the follower downwards against the recovery force of the springs 26.
  • the suppressing force on follower 24 decreases and the springs 26 pull up the follower vertically.
  • the follower 24 shifts up or down together with the corona electrode 23 in accordance with the shape of the member 21, a constant distance being maintained between the surface of the member 21 and the electrode 23, thereby producing substantially uniform charging on the surface of member 21.
  • FIGS. 3 and 4 illustrate charging apparatus useful for charging an irregularly shaped plate 31 having a rugged structure along any direction.
  • a spherical follower 33 which preferably has a radius smaller than the minimum radius of curvature of plate 31 is rotatably supported by and on the top of a vertical member 32.
  • a stylus electrode 35 vertically held by a holder 34 is also provided.
  • the follower 33 and the electrode 35 are mechanically united with a connector (not shown) in such a manner that a perpendicular line including the stylus electrode 35 passes the center of the sphere 33 with a predetermined distance therebetween suitable for charging the surface of plate 31, the distance being adjustable depending upon the shape of plate 31.
  • Plate 31 is placed on fixed supporting rods 37 via springs 36 and supports 38. As the springs are compressed by the gravitational force of the plate, the supports 38 are lowered until the rear surface of plate 31 contacts follower 33. The assembly is set in such a manner that the follower 33 is always in contact with the rear surface of plate 31.
  • the assembly comprising the follower 33 and the electrode 35, a high electrical potential being applied to electrode 35, scans the plate 31 in the direction perpendicular to that of the movement of the plate at a constant speed whereby corona ions generated at the electrode impinges upon the surface of the member 31.
  • follower 33 rises or falls together with the corona electrode 35 in accordance with the shape of the plate 31. A constant distance is thus maintained between the surface of plate 31 and the electrode 35.
  • the plate 31 may be moved in the direction perpendicular to arrow 39 reciprocally at the same time it is moving in the direction of arrow 39.
  • the charging operation may be controlled to start when the leading edge of he plate member first comes in contact with member 29 (support member 38 in FIGS. 3 and 4). Similarly, the charging terminates when the trailing edge of the plate member comes into contact with members 29 or 38. Accordingly, a control unit (not shown) can be utilized such that the corona charging circuit is closed when the leading edge passes the member 29 or 38 and opened when the trailing edge passes either member.
  • the spacing between the follower 24 and members 29 may be selected to be equal to. half the width of the charge pattern which will be formed on the stationary plate under the electrode.
  • the spacing is selected to be equal to the radius of the circular charge pattern which will be formed on the stationary plate by the pin electrode. The width or radius of such patterns can be altered depending on the distance between the corona electrode and the plate surface, and the potential applied to the electrode.
  • the apparatus described above has a rather wide versatility for use in charging members having rugged, complex and irregular shaped surfaces.
  • another type of charging device is also useful since it is capable of se- -quentially charging a portion of a number of members which have a common, relatively simple configuration.
  • FIG. 5 illustrates a device adapted to charge a portion of an electrophotographic layer provided on the outer surface of a plate having a crosssection of a circular arc.
  • the charge formed on the surface of plate 41 is in the form of a doughnut.
  • the plate 41 is placed on a pair of rollers 44 rotatably held by a pair of fixed shafts 43 which stretch out of a pair of side boards 42 maintained at ground potential.
  • Each of the rollers 44 is always in contact with the inner or rear surface of the plate 41.
  • a support 46 vertically rising upright from a motor 45 is fixed on the plate either mechanically, magnetically or electromagnetically.
  • One of the rollers 44 (at the left hand of the figure) serves as the follower of the present invention.
  • a pin electrode for corona discharge 47 is provided on the vertical line running through the center of the roller 44 with a spacing suitable for charging the outer surface of plate 41.
  • the electrode 47 is fixed on an insulating support 48 made of, for example, acrylic resin.
  • the support 48 connects each of the side boards 42.
  • a charge pattern results having the form of a doughnut having a width equal to the diameter of the circular corona pattern which would occur without relative movement between the plate and the electrode.
  • roller 44 other than the one acting as the follower can shift vertically and is pushed upwards by means of spring, it can be also used to charge plates of various configurations having relatively mild rises and falls along the circular direction of the plate.
  • an electrophotographic recording member comprising a conductive or semi-conductive substrate and a photoconductive insulating layer provided thereon has been subjected to charging with the use of the apparatus in accordance with the present invention.
  • the charged member was assumed to be subsequently exposed to an image of light and shadow to form an electrostatic latent image.
  • the apparatus can also be used to charge and electrically insulating (not photoconductive) coating provided on a curved substrate.
  • the charged coating may be, for example, utilized for ionography wherein the charged member is exposed to imagewise X-ray radiation whereby an ionized ambient atmosphere helps the surface charge to dissipate to form an electrostatic latent image.
  • Apparatus for uniformly charging a surface of a non-planar member having a substantially uniform thickness as said non-planar member is moved in a predetermined direction comprising:
  • a corona discharge electrode disposed adjacent said surface at one side of said non-planar member
  • a potential source for applying an electrical potential to said corona discharge electrode, whereby a substantially uniform charge is formed on said surface.
  • non-planar member comprises a conductive substrate and a photoconductive insulating layer overlying said conductive substrate to define said surface, and said follower member underlies and is maintained in contact with said conductive substrate.
  • said non-planar member has a corrugation-like deformity occurring along the direction of movement of said nonplanar member
  • said discharge electrode comprises a corona wire disposed transverse to the direction of movement of said non-planar member, said wire having a length at least equal to the width of said planar memher.

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • General Physics & Mathematics (AREA)
  • Electrostatic Charge, Transfer And Separation In Electrography (AREA)
US00224990A 1969-11-26 1970-02-09 Device for uniformly charging a non-planar electrophotographic plate Expired - Lifetime US3743830A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP44094931A JPS4910059B1 (enrdf_load_stackoverflow) 1969-11-26 1969-11-26

Publications (1)

Publication Number Publication Date
US3743830A true US3743830A (en) 1973-07-03

Family

ID=14123697

Family Applications (1)

Application Number Title Priority Date Filing Date
US00224990A Expired - Lifetime US3743830A (en) 1969-11-26 1970-02-09 Device for uniformly charging a non-planar electrophotographic plate

Country Status (3)

Country Link
US (1) US3743830A (enrdf_load_stackoverflow)
JP (1) JPS4910059B1 (enrdf_load_stackoverflow)
CA (1) CA939734A (enrdf_load_stackoverflow)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3918403A (en) * 1973-11-23 1975-11-11 Xerox Corp Corona transfer mechanism
US3922548A (en) * 1973-05-18 1975-11-25 Rank Xerox Ltd Corona charging device and support arrangement
US3978380A (en) * 1975-03-26 1976-08-31 Coulter Information Systems, Inc. Reciprocating corona producing apparatus
US4467200A (en) * 1980-12-01 1984-08-21 Klaus Kalwar Device for the surface treatment of thermoplastic moldings by corona discharge
US4636640A (en) * 1983-07-01 1987-01-13 Pillar Corporation Corona discharge electrode assembly
US5083959A (en) * 1990-08-13 1992-01-28 Rca Thomson Licensing Corp. CRT charging apparatus
US5132188A (en) * 1990-08-13 1992-07-21 Rca Thomson Licensing Corp. Method for charging a concave surface of a CRT faceplate panel
US5335050A (en) * 1993-09-13 1994-08-02 Xerox Corporation Adjustable support assembly
US5676791A (en) * 1991-12-11 1997-10-14 Alusuisse Technology & Management Ltd. Device for producing extrusion-coated laminates
EP0741339A3 (en) * 1995-05-04 1998-06-17 Xerox Corporation Modular charging device for imaging system
US10976358B2 (en) * 2018-11-07 2021-04-13 The Boeing Company Surface charging systems and method for charging a non-planar surface

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS50150878A (enrdf_load_stackoverflow) * 1974-05-25 1975-12-03
JPS5122765U (enrdf_load_stackoverflow) * 1974-08-10 1976-02-19
JPS5354385U (enrdf_load_stackoverflow) * 1976-10-12 1978-05-10
JPS55178191U (enrdf_load_stackoverflow) * 1979-06-06 1980-12-20

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2747152A (en) * 1951-08-01 1956-05-22 Air Reduction Torch spacing control
US3183352A (en) * 1960-11-23 1965-05-11 American Can Co Corona treating of shaped articles
US3303401A (en) * 1962-07-20 1967-02-07 Azoplate Corp Method and apparatus for imparting an electrostatic charge to a layer of insulating material

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2747152A (en) * 1951-08-01 1956-05-22 Air Reduction Torch spacing control
US3183352A (en) * 1960-11-23 1965-05-11 American Can Co Corona treating of shaped articles
US3303401A (en) * 1962-07-20 1967-02-07 Azoplate Corp Method and apparatus for imparting an electrostatic charge to a layer of insulating material

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3922548A (en) * 1973-05-18 1975-11-25 Rank Xerox Ltd Corona charging device and support arrangement
US3918403A (en) * 1973-11-23 1975-11-11 Xerox Corp Corona transfer mechanism
US3978380A (en) * 1975-03-26 1976-08-31 Coulter Information Systems, Inc. Reciprocating corona producing apparatus
US4467200A (en) * 1980-12-01 1984-08-21 Klaus Kalwar Device for the surface treatment of thermoplastic moldings by corona discharge
US4636640A (en) * 1983-07-01 1987-01-13 Pillar Corporation Corona discharge electrode assembly
US5083959A (en) * 1990-08-13 1992-01-28 Rca Thomson Licensing Corp. CRT charging apparatus
US5132188A (en) * 1990-08-13 1992-07-21 Rca Thomson Licensing Corp. Method for charging a concave surface of a CRT faceplate panel
US5676791A (en) * 1991-12-11 1997-10-14 Alusuisse Technology & Management Ltd. Device for producing extrusion-coated laminates
US5335050A (en) * 1993-09-13 1994-08-02 Xerox Corporation Adjustable support assembly
EP0741339A3 (en) * 1995-05-04 1998-06-17 Xerox Corporation Modular charging device for imaging system
US10976358B2 (en) * 2018-11-07 2021-04-13 The Boeing Company Surface charging systems and method for charging a non-planar surface

Also Published As

Publication number Publication date
CA939734A (en) 1974-01-08
JPS4910059B1 (enrdf_load_stackoverflow) 1974-03-08

Similar Documents

Publication Publication Date Title
US3743830A (en) Device for uniformly charging a non-planar electrophotographic plate
EP0010375B1 (en) Electrostatographic processing system
US3684364A (en) Lift off electrode
US2885556A (en) Simultaneous charging device and method
US3850519A (en) Xerographic image transfer apparatus
US2833648A (en) Transfer of electrostatic charge pattern
US2968553A (en) Xerographic apparatus and method
US3084061A (en) Method for formation of electro-static image
US3220833A (en) Electrostatic printing method
US2856533A (en) Moving wire corona
US3739748A (en) Donor for touchdown development
EP0274895B1 (en) Corona charging device
US3696783A (en) Automated touchdown developement system
US3611074A (en) Corona discharge device
US3234904A (en) Device for tesiprinting
US3456109A (en) Method and means for photoelectrostatic charging
US3655966A (en) Electric charging device for electrophotography
US3997688A (en) Developing an electrical image
US3549251A (en) Electrophotographic method and apparatus
GB1057006A (en) A facsimile printer
US4409603A (en) Electrographic method and apparatus
US4763157A (en) Transfer roller
US3592541A (en) Copying system using electrogasdynamics
US3449568A (en) Corona discharge apparatus for creating an electrostatic charge pattern on a xerographic surface
CA1044958A (en) Method and apparatus for developing an electrical image