US3851966A - Reproduction apparatus - Google Patents

Reproduction apparatus Download PDF

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Publication number
US3851966A
US3851966A US00314218A US31421872A US3851966A US 3851966 A US3851966 A US 3851966A US 00314218 A US00314218 A US 00314218A US 31421872 A US31421872 A US 31421872A US 3851966 A US3851966 A US 3851966A
Authority
US
United States
Prior art keywords
image
photoconductive surface
original
toner
paper
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
US00314218A
Other languages
English (en)
Inventor
E Reehil
E Steiner
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
Priority to US00314218A priority Critical patent/US3851966A/en
Priority to CA178,886A priority patent/CA1018239A/en
Priority to DE19732342898 priority patent/DE2342898A1/de
Priority to BR8038/73A priority patent/BR7308038D0/pt
Priority to NL7315036A priority patent/NL7315036A/xx
Priority to FR7343571A priority patent/FR2209953B1/fr
Priority to JP48137226A priority patent/JPS4990946A/ja
Priority to GB5718373A priority patent/GB1449180A/en
Priority to BE138734A priority patent/BE808482A/xx
Priority to IT42943/73A priority patent/IT1033521B/it
Application granted granted Critical
Publication of US3851966A publication Critical patent/US3851966A/en
Priority to CA270,632A priority patent/CA1041157A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • 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
    • G03G15/50—Machine control of apparatus for electrographic processes using a charge pattern, e.g. regulating differents parts of the machine, multimode copiers, microprocessor control
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G13/00—Electrographic processes using a charge pattern
    • G03G13/06—Developing
    • G03G13/08—Developing using a solid developer, e.g. powder developer
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G13/00—Electrographic processes using a charge pattern
    • G03G13/22—Processes involving a combination of more than one step according to groups G03G13/02 - G03G13/20
    • 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
    • G03G15/14—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base
    • G03G15/16—Apparatus for electrographic processes using a charge pattern for transferring a pattern to a second base of a toner pattern, e.g. a powder pattern, e.g. magnetic transfer
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G2215/00—Apparatus for electrophotographic processes
    • G03G2215/00362—Apparatus for electrophotographic processes relating to the copy medium handling
    • G03G2215/00367—The feeding path segment where particular handling of the copy medium occurs, segments being adjacent and non-overlapping. Each segment is identified by the most downstream point in the segment, so that for instance the segment labelled "Fixing device" is referring to the path between the "Transfer device" and the "Fixing device"
    • G03G2215/00405—Registration device
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G2215/00—Apparatus for electrophotographic processes
    • G03G2215/00362—Apparatus for electrophotographic processes relating to the copy medium handling
    • G03G2215/00535—Stable handling of copy medium
    • G03G2215/00548—Jam, error detection, e.g. double feeding
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G2215/00—Apparatus for electrophotographic processes
    • G03G2215/00362—Apparatus for electrophotographic processes relating to the copy medium handling
    • G03G2215/00535—Stable handling of copy medium
    • G03G2215/00603—Control of other part of the apparatus according to the state of copy medium feeding

Definitions

  • a number of images may be disposed on the belt before the sheet of paper adapted to receive the foremost image is fed from the paper supply station.
  • these electrostatic images would proceed through the developer and the transfer rollers to the cleaning station of the-machine wherein the-belt is ordinarily cleaned prior to the charging thereof and exposure of a new image. If the paper is not present at the transfer station when the developed image arrives thereat, the xerographic surface with the toner-image thereon can cause numerous problems. Toner may be transferred from the belt to the transfer rollers.
  • the toner that is not transferred to the transfer roll will be conveyed by movement of the belt to the cleaning station of the machine. Since the cleaning station is designed to remove the residual toner remaining after the majority of the toner is transferred to the copy sheet, in the event that a copy sheet is not present at the transfer rolls, excess quantities of toner willreach the cleaning station, putting an undue load thereon. Besides the problems presented at the transfer station and the cleaning station, this type of operation is extremely wasteful of xerographic toner.
  • This invention relates to a method for minimizing problems in a zerographic machine caused by the misfeed of copy paper therethrough by discharging the electrostatic image on the photoconductive surface before that portion of the surface reaches the developer station, tie-energizing the developer, and removing the electrical bias on the transfer rolls to prevent transfer of toner thereto and minimize the possibilityof carrying excess toner to the cleaning station of the. machine.
  • FIG. 1 is a schematic sectional view of a reproduction machine showing the various processing stations therein; and, L
  • FIG. 2 is a schematicblock diagram of the control system to provide a programmed shutdown of the machine in the event of a paper misfeed.
  • FIG. 1 For a general understanding of an electrostatic processing system in which the invent-ion may be incorporated, reference is bad to FIG. 1 in which various components of a system are schematically illustrated.
  • a light image of the original to be reproduced is projected onto the sensitized surface of a zerographic plate to form an electrostatic latent image thereon.
  • the latent image is developed with an oppor sitely charged developing material comprising carrier beads and smaller powder particles triboelectrically adhering thereto to "form a xerographic powder image corresponding to the latent image on the plate surface.
  • the powder image is then electrostatically transferred to a support surface to which it may be fixed by a fusing device whereby the powder image is caused permanently to adhere to the support surface.
  • the electrostatically attractable developing material commonly used in electrostatic reproduction systems comprises a pigmented resinous powder hereinafter referred to as toner", and carrier" of larger granular beads formed from a material removed in the triboelectric series from the toner so that a triboelectric charge is generated between the toner powder and the granular carrier.
  • the carrier also provides mechanical control .sothat the toner can be readily handled and brought into contact with the exposed xerographic surface where the toner is attracted to the electrostatic latent image from the carrier to produce a visible powder image on the xerographic surface.
  • an original D to be copied is placed upon a transparent support platen P, fixedly arranged in anillumination assembly generally indicated'by the reference numeral 10. While upon the platen, an illumination system L comprising two or more lamps and reflectors is flash energized to direct light rays upon the original to produce image rays corresponding to the informational areas on the original.
  • the image rays are projected by means of an optical system 11 to an exposure station A for exposing the photosensitive surface of a moving xerographic plate in the form of a flexible photoconductive belt 12.
  • a corona device 13 indicated at a belt run extending bement of the electrostatic image.
  • a discharge device preferably a flourescent lamp'17 is provided adjacent support roller 16 for reasons to be explained hereinafter.
  • the electrostatic image passes around the roller 16 to a developer station B located at a third run of the belt in which there is positioned developing apparatus generally indicated by the reference numeral 18.
  • the developer apparatus 18 comprises a plurality of brushes adapted for rotation by a suitable motor 19 to carry developer along the adjacent surface of the upwardly moving inclined .photoconductive belt 12 to provide develop-
  • the developed electrostatic image is transported be the belt 12 to a transfer station C located at a point of tangency on the belt around the drive roller whereat a sheet of copy paper is moved at a speed in synchronism with the moving belt in order to accomplish transfer of a properly registered developed imagejA transfer roller 20 is provided at transfer stationC for contacting the upper surface of the copy paper to assure good contact between the copy paper and the belt 12 during transfer of the toner imagefrom the belt tothe paper.
  • An electrical bias may be provided on roller 20 to attract the toner from belt 12 to the-copy paper.
  • a copy sheet supplying apparatus comprising a main paper feed supply 21 and an auxiliary paperifeed supply 22.
  • Each of the'paper supplies is adapted to separatesheets from their respective supply stacks and to transport the sheets to a sheet registration station and eventually into contact with the developedimage on thebelt as the same is carried around the drive roller 1 5.
  • -Control means 23 are operatively associated with each of the paper supply mechanisms 21, 22 and the flash illumination device L for producing an electrostatic latent image on the; belt 12 to present a developed image at the transfer station C in timed sequence with the arrival of a sheet of paper, and is coordinated with the activation of other processing and control devices at the precise time that these elements are to function for their intended purpose.
  • a paper sensing'device 24 is positioned adjacent the paper. path between the paper supply mechanism 21 and 22 and the trnsfer station C, to determine if the paper .is fed therefrom at the proper time relative to the image on the photoreceptor belt.
  • the developed image is transferred to a sheet of paper, it is stripped from the belt 12 and conveyed by Y conveying system 25 into a fuser apparatus generally indicated by reference numeral 26 whereinthe developed and transferred xerographic powder image on the sheet material is affixed thereto; After fusing, the finished copy isdischarged from the apparatus by a conve yor 27 at a suitable point for collection externally of the apparatus.
  • control system 23 is adapted to immediately energizevlamp 17, deactivate the developer motor 19, remove the electrical bias on transfer roller 20 and move the transfer roller out of contact with the belt by a suitable mechanism (not shown).
  • the cleaning station will onl'y'be required to remove toner from one or two developed images rather than all the images that were on the belt prior to the detection of the misfeed.
  • What is claimed isi 1.
  • a reproduction machine adapted for making copies of an original through a plurality of process steps continuously energizing the transfer roller and main- 'taining the transfer roller in contact with the photoconductive surface during a normal copy run; removing the electrical bias on the transfer roller moving the transfer roller away from the photoconductive surface in the event of a paper misfeed to prevent transfer of toner to the roller; and, de-energizing the developer to prevent development of latent electrostatic images passing by the developer subsequent to a paper misfeed. 2.
  • a method to minimize toner consumption and toner contamination-of a reproduction machine further including a step of discharg-' ing the latent electrostatic images on the photodonduc tive surface before the imaged areas reach the developer to prevent development thereof in the event of a paper misfeed.
  • a reproduction machine adapted for making copies of an original through a plurality of process steps including exposure of the original to form a latent electrostatic image of the original on a photoconductive surface, developing the image to provide a toner image of the original on the photoconductive surface, and holding the copy paper against the toner image by suitable holding means adapted for continuous contact 6 v with the photoconductive surface during normal mation of the machine comprising the steps of; chine operation to transfer the toner image to the copy discharging a portion of the latent imaged areas on paper, a method to minimize toner consumption and the photoconductive surface in the event of a paper toner contamination of the machine comprising the misfeed and preventing development of undissteps of: 5 charged imaged areas on the photoconductive surmoving the holding means away from the photoconface by de-energizing the developer.
  • a method for automatically producing copies of an vent transfer of toner thereto and discharging latent original comprising the steps of; image areas on the photoconductive surface in the providing an electrostatic charge pattern of the origievent of a paper misfeed to prevent development 0 nal on a photoconductive surface; thereof. developing the charge pattern wit an electrically at- 4.
  • a method to minimize toner consumption and tractable powder as the charge pattern on the photoner contamination of the machine according to claim toconductive surface passes a developer station to 3 further including the step of preventing development provide a powder image on the photoconductive of the imaged areas that are not discharged by desurface in conformity with the original; energizing the developer.
  • a reproduction machine adapted for making tive surface in synchronism with the developed copies of an original through a plurality of process steps image thereon for contact with the image to transincluding exposure of the original to form a latent elecfer the powder image to the copy paper; and, trostatic image of the original on a photoconductive discharging the electrostatic charge pattern in the surface, developing the image to provide a toner image event of a paper misfeed to prevent development of the original on the photoconductive surface, and of the charge pattern as the photoconductive surtransferring the toner image to a copy paper, a method face moves past the developer station. to minimize toner consumption and toner contamina-

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Control Or Security For Electrophotography (AREA)
  • Combination Of More Than One Step In Electrophotography (AREA)
  • Paper Feeding For Electrophotography (AREA)
  • Cleaning In Electrography (AREA)
US00314218A 1972-12-11 1972-12-11 Reproduction apparatus Expired - Lifetime US3851966A (en)

Priority Applications (11)

Application Number Priority Date Filing Date Title
US00314218A US3851966A (en) 1972-12-11 1972-12-11 Reproduction apparatus
CA178,886A CA1018239A (en) 1972-12-11 1973-08-15 Reproduction apparatus
DE19732342898 DE2342898A1 (de) 1972-12-11 1973-08-24 Verfahren zur abschaltung elektrostatischer kopiergeraete bei papierausfall
BR8038/73A BR7308038D0 (pt) 1972-12-11 1973-10-15 Processo para a reproducao automatica de copias deoriginal entador em uma maquina de reproducao e processo para minimizar o consumo e a contaminacao
NL7315036A NL7315036A (ko) 1972-12-11 1973-11-01
FR7343571A FR2209953B1 (ko) 1972-12-11 1973-12-06
JP48137226A JPS4990946A (ko) 1972-12-11 1973-12-07
GB5718373A GB1449180A (en) 1972-12-11 1973-12-10 Electrostatographic imaging apparatus
BE138734A BE808482A (fr) 1972-12-11 1973-12-11 Machine a copier electrostatique
IT42943/73A IT1033521B (it) 1972-12-11 1973-12-18 Procedimento di riproduzione del tipo xerografico
CA270,632A CA1041157A (en) 1972-12-11 1977-01-28 Reproduction apparatus

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US00314218A US3851966A (en) 1972-12-11 1972-12-11 Reproduction apparatus

Publications (1)

Publication Number Publication Date
US3851966A true US3851966A (en) 1974-12-03

Family

ID=23219074

Family Applications (1)

Application Number Title Priority Date Filing Date
US00314218A Expired - Lifetime US3851966A (en) 1972-12-11 1972-12-11 Reproduction apparatus

Country Status (10)

Country Link
US (1) US3851966A (ko)
JP (1) JPS4990946A (ko)
BE (1) BE808482A (ko)
BR (1) BR7308038D0 (ko)
CA (1) CA1018239A (ko)
DE (1) DE2342898A1 (ko)
FR (1) FR2209953B1 (ko)
GB (1) GB1449180A (ko)
IT (1) IT1033521B (ko)
NL (1) NL7315036A (ko)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2315712A1 (fr) * 1975-06-24 1977-01-21 Oce Van Der Grinten Nv Appareil copieur
US4046467A (en) * 1975-05-14 1977-09-06 Xerox Corporation Zoom lens copier
FR2374241A1 (fr) * 1976-12-20 1978-07-13 Ibm Machine de production de copies comportant une repetition de la prise de feuille
US4243313A (en) * 1977-12-06 1981-01-06 Canon Kabushiki Kaisha Image forming device
US4272183A (en) * 1978-06-21 1981-06-09 Minolta Camera Kabushiki Kaisha Control system responsive to eraser malfunctions in electrophotographic copying machines
US4627711A (en) * 1985-09-30 1986-12-09 Xerox Corporation Machine shutdown control
US4763164A (en) * 1977-03-02 1988-08-09 Canon Kabushiki Kaisha Image forming apparatus
US4763162A (en) * 1981-02-27 1988-08-09 Canon Kabushiki Kaisha Copy sheet feed controller for an electrostatic copier
US4796055A (en) * 1986-01-28 1989-01-03 Minolta Camera Kabushiki Kaisha Recording apparatus incorporating manual paper feeder
DE3935618A1 (de) * 1988-10-31 1990-05-03 Toshiba Kawasaki Kk Abbildungsvorrichtung
US6212339B1 (en) * 1999-03-17 2001-04-03 Sharp Kabushiki Kaisha Image forming apparatus with discharging exposure after shutdown

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5370826A (en) * 1976-12-07 1978-06-23 Oki Electric Ind Co Ltd Electrophotographic printer
JPS548538A (en) * 1977-06-21 1979-01-22 Canon Inc Controller of developing device
JPS56146155A (en) * 1980-04-15 1981-11-13 Mita Ind Co Ltd Electrostatic copying machine
JPS6114650A (ja) * 1984-06-29 1986-01-22 Minolta Camera Co Ltd 複写制御装置
JPS6114651A (ja) * 1984-06-29 1986-01-22 Minolta Camera Co Ltd 複写制御装置
JPS6240480A (ja) * 1985-08-16 1987-02-21 Konishiroku Photo Ind Co Ltd 画像記録装置

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3620616A (en) * 1969-06-04 1971-11-16 Xerox Corp Transfer drum withdrawal apparatus
US3661452A (en) * 1968-05-24 1972-05-09 Xerox Corp Xerographic reproduction machine
US3674363A (en) * 1968-06-10 1972-07-04 Xerox Corp Sheet feeding apparatus
US3717122A (en) * 1971-03-01 1973-02-20 Xerox Corp Magnetic gate
US3751156A (en) * 1971-10-21 1973-08-07 Agfa Gevaert Ag Electrostatic copying apparatus with means for preventing contamination of transfer material

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE536877A (ko) * 1954-03-29
US2909971A (en) * 1954-03-29 1959-10-27 Ibm Printing machine
US2889758A (en) * 1954-12-24 1959-06-09 Ibm Electrophotographic printer
US3689146A (en) * 1969-05-02 1972-09-05 Canon Kk Electrophotographic copying machine
GB1300267A (en) * 1969-06-04 1972-12-20 Xerox Corp Transfer member withdrawal apparatus

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3661452A (en) * 1968-05-24 1972-05-09 Xerox Corp Xerographic reproduction machine
US3674363A (en) * 1968-06-10 1972-07-04 Xerox Corp Sheet feeding apparatus
US3620616A (en) * 1969-06-04 1971-11-16 Xerox Corp Transfer drum withdrawal apparatus
US3717122A (en) * 1971-03-01 1973-02-20 Xerox Corp Magnetic gate
US3751156A (en) * 1971-10-21 1973-08-07 Agfa Gevaert Ag Electrostatic copying apparatus with means for preventing contamination of transfer material

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4046467A (en) * 1975-05-14 1977-09-06 Xerox Corporation Zoom lens copier
FR2315712A1 (fr) * 1975-06-24 1977-01-21 Oce Van Der Grinten Nv Appareil copieur
FR2374241A1 (fr) * 1976-12-20 1978-07-13 Ibm Machine de production de copies comportant une repetition de la prise de feuille
US4763164A (en) * 1977-03-02 1988-08-09 Canon Kabushiki Kaisha Image forming apparatus
US4243313A (en) * 1977-12-06 1981-01-06 Canon Kabushiki Kaisha Image forming device
US4272183A (en) * 1978-06-21 1981-06-09 Minolta Camera Kabushiki Kaisha Control system responsive to eraser malfunctions in electrophotographic copying machines
US4763162A (en) * 1981-02-27 1988-08-09 Canon Kabushiki Kaisha Copy sheet feed controller for an electrostatic copier
US4627711A (en) * 1985-09-30 1986-12-09 Xerox Corporation Machine shutdown control
US4796055A (en) * 1986-01-28 1989-01-03 Minolta Camera Kabushiki Kaisha Recording apparatus incorporating manual paper feeder
DE3935618A1 (de) * 1988-10-31 1990-05-03 Toshiba Kawasaki Kk Abbildungsvorrichtung
US6212339B1 (en) * 1999-03-17 2001-04-03 Sharp Kabushiki Kaisha Image forming apparatus with discharging exposure after shutdown

Also Published As

Publication number Publication date
JPS4990946A (ko) 1974-08-30
GB1449180A (en) 1976-09-15
IT1033521B (it) 1979-08-10
BE808482A (fr) 1974-03-29
CA1018239A (en) 1977-09-27
FR2209953A1 (ko) 1974-07-05
FR2209953B1 (ko) 1976-11-19
NL7315036A (ko) 1974-01-25
BR7308038D0 (pt) 1974-10-22
DE2342898A1 (de) 1974-06-12

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