US2807233A - Electrophotographic printing machine - Google Patents

Electrophotographic printing machine Download PDF

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Publication number
US2807233A
US2807233A US419314A US41931454A US2807233A US 2807233 A US2807233 A US 2807233A US 419314 A US419314 A US 419314A US 41931454 A US41931454 A US 41931454A US 2807233 A US2807233 A US 2807233A
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United States
Prior art keywords
web
printing
drum
roller
cylinder
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Expired - Lifetime
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US419314A
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English (en)
Inventor
Clyde J Fitch
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International Business Machines Corp
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International Business Machines Corp
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Filing date
Publication date
Priority to BE536878D priority Critical patent/BE536878A/xx
Priority to NL195972D priority patent/NL195972A/xx
Priority to BE536877D priority patent/BE536877A/xx
Application filed by International Business Machines Corp filed Critical International Business Machines Corp
Priority to US419392A priority patent/US2859673A/en
Priority to US419314A priority patent/US2807233A/en
Priority to US419702A priority patent/US2909971A/en
Priority to FR1141378D priority patent/FR1141378A/fr
Priority to GB8738/55A priority patent/GB766426A/en
Priority to GB8737/55A priority patent/GB768020A/en
Priority to CH333951D priority patent/CH333951A/fr
Priority to CH333952D priority patent/CH333952A/fr
Application granted granted Critical
Publication of US2807233A publication Critical patent/US2807233A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • 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
    • G03G15/22—Apparatus for electrographic processes using a charge pattern involving the combination of more than one step according to groups G03G13/02 - G03G13/20
    • G03G15/28—Apparatus for electrographic processes using a charge pattern involving the combination of more than one step according to groups G03G13/02 - G03G13/20 in which projection is obtained by line scanning
    • G03G15/30—Apparatus for electrographic processes using a charge pattern involving the combination of more than one step according to groups G03G13/02 - G03G13/20 in which projection is obtained by line scanning in which projection is formed on a drum
    • 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
    • G03G15/1665—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 by introducing the second base in the nip formed by the recording member and at least one transfer member, e.g. in combination with bias or heat
    • G03G15/167—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 by introducing the second base in the nip formed by the recording member and at least one transfer member, e.g. in combination with bias or heat at least one of the recording member or the transfer member being rotatable during the transfer
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
    • G06K1/00—Methods or arrangements for marking the record carrier in digital fashion
    • G06K1/14—Methods or arrangements for marking the record carrier in digital fashion by transferring data from a similar or dissimilar record carrier
    • G06K1/18—Methods or arrangements for marking the record carrier in digital fashion by transferring data from a similar or dissimilar record carrier by transferring data from one type of record carrier on to another type of record carrier, e.g. from magnetic tape to punched card
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S101/00—Printing
    • Y10S101/37—Printing employing electrostatic force

Definitions

  • the embodiment of this invention pertains to apparatus for elfecting a transfer of a visible image from an image carrying member, to a print receiving material, such as a web of paper for example, and has for its purpose to provide an improved image, or print, transfer apparatus by which selective electric printing may be effected.
  • the embodiment of this invention pertains to so'called xerographic machines capable of making a duplicate of information appearing on source records, such as record cards for example, on a print receiving strip by means of a transfer or printing process.
  • xerography is a term applied to a printing process in which electrostatic latent images are rendered visible by a suitable electrically charged toner powder, the resulting powder image thereafter being transferred and fixed to a print receiving material.
  • Another broad object of this invention is to provide a selective printing electric printer whereby only selected information appearing at a certain place, or places, on a source record, is transferred from the source record onto a copy record.
  • Another object of this invention is to provide an electrophotographic printer having an improved image transfer apparatus associated therewith for transferring by electric power only select electrically charged powder images.
  • Another object of this invention is to provide a xerographic printer having an image transfer'apparatus associated therewith which is capable of selectively effecting or disabling the image transfer or printing process 9
  • a still another object of this invention is to provide an electrophotographic printer having an image transfer apparatus which requires lower voltages than used heretofore.
  • Fig. l is a somewhat diagrammatic view of an electrophotographic printer utilizing alshifting transfer roller apparatus at the image transfer station.
  • Fig. 2 is'a somewhat diagrammaticview of an electrophotographic printer utilizing an electric pulse controlled transfer apparatus at the image transfer station.
  • Fig. 3 is a flow diagram depicting generally the operations required in order to place the image of source record information upon a print receiving a copy record.
  • Fig. 4 is a somewhat diagrammatic view of the transfer apparatus and associated mechanism taken along the plane 4-4 of Fig. l.
  • Fig. 5 is a somewhat diagrammatic view of the transfer apparatus and associated mechanism taken along the plane 5-5 of Fig. 2.
  • record cards 20 to be operated on are stacked in hopper 21, and are fed, one by one, by a conventional picker (not shown) of the type in Patent No. 2,448,830 issued to J. J. Robbins et al., each card cycle out of card hopper 21 to stacker 22. Successive pairs of feed rolls 23 and 24 cause cards 20 to be advanced during successive card cycles past the optical projector apparatus 25.
  • Apparatus 25 includes a single light ray projector 26. which throws a concentrated band of parallel light rays upon the constricted center of the aperture in member 27. Inasmuch as the reflecting surface of a mirror 28 is over the aperture of member 27, the light band is caused to impinge upon the surface of xerographic drum 29 when there are no cards present between member 27 and mirror 28.
  • each of the record cards 20 is shown to include printed information which is represented and identified by block 30. Due to the fact that the surface of each card 20 has a light reflecting property," as the cards are fed past projector 25 (see also Fig. 1), and between member 27 and mirror 28, light rays are directed onto the surface of drum 29 except when the symbols included within the printed information identified by the reference numeral 30, are not brought into alignment with the aperture of member 27. It may be-seen then that apparatus 25 includes a conventional light scanning means for transferring the image of the aforesaid printed information onto the surface of the xerographic drum 29.
  • Xerographic drum 29 includes an electrically conducting cylinder 35 and a printing element, or plate, 36 in the form of an electrically insulating or non-conducting image layer.
  • This layer is carried by a sheet of any flexible metal or other conductive material 37 that enables its being flexed around and attached to the cylinder 35, the sheet 37 being secured to the cylinder in any of the conventional ways of attaching a printing plate to a supporting cylinder, as by means of suitable clamping devices. It is necessary, however, that the backing sheet 37 of the 7 image layer plate 36 is in good electrical contact with thereon by-electrostatic charging,
  • the electrically conductive backing sheet 37 is preferably coated with a light sensitive photoconductive insulating-material, such as plate 36, which may have a powder image produced exposure and powder development, after which the powder image can be made into a permanent print image by transferring and fixing the developed powder image onto a print receiving material such as paper strip, or web, 38.
  • a light sensitive photoconductive insulating-material such as plate 36, which may have a powder image produced exposure and powder development, after which the powder image can be made into a permanent print image by transferring and fixing the developed powder image onto a print receiving material such as paper strip, or web, 38.
  • xerographic drum 29 With the feeding of record cards 20 from hopper 21 to stacker 22, xerographic drum 29 is caused to rotate at a speed which is correlated to the record card feed speed, by means of drive shaft 31. As successive incremental areas of the light sensitive photoconductive plate 36 are moved past ion-producing unit 32, the aforesaid plate is electrostatically charged by the ion-producing source.
  • Carlson Patent No. 2,588,699 may be referred to for a complete showing and description of the afore-mentioned electrophotographic charging apparatus.
  • the powder in chamber 39 may be a finely powdered dye, pigment, carbon or other black or colored substance, or in some cases a white powder such as zinc oxide.
  • a suitable electroscopic developer powder, or toner, is described in Copley Patent No. 2,659,670
  • the transfer roller comprises an inner-metallic portion 41 and an outer portion 42 of very resilient or yielding material having a high electrical resistance, as for example, a layer of soft semi-conducting rubber.
  • the transfer roller requires a resilient outer portion so as to compensate for mechanical irregularities of the xerographic drum surface, and to prevent mechanical damage to the photoconductive surface thereof.
  • the conductive rubber is preferably a very poor conductor of electricity, and may have an electrical resistivity of approximately ohms per cubic centimeter.
  • the resistance value is not too critical and it may be greater than the aforementioned value. However, the resistance value is preferably not less than 10 ohms per cubic centimeter.
  • Transfer roller 40 is biased by springs 43 (see also Fig. 4) in the direction of photoconductive plate 36 so that web 38 is sandwiched therebetween.
  • the transfer roller is supported by the shaft is journaled in arms 45.
  • the latter arms are each at- 44 thereof which, in turn,
  • cam follower arms 46 which are also fixed to shaft 47 whereon cam follower roller 48 is mounted.
  • Web feed control arms 49 having feed roller 50 attached thereto are also fixed to shaft 47 so that arms 45, 46 and 49 act in unison.
  • the afore-mentioned arms are pivotally mounted upon shaft 54, the said shaft having idler roller rotatably mounted thereon, and being fixed in printing machine support frames, such as frame 53 for example.
  • web 38 is fed from reel 56 past drag rollers 57, around idler roller 55 and transfer roller 40, between fixing rollers 58, feed rollers 50 and 59, and rollers 60, to reel 61.
  • a line pressure such as is afforded by the pressure fixing rolls 58 (Fig. 1) and 158 ('Fig. 2).
  • a sufficient line pressure for example 500 pounds per lineal inch of contact, will cause the toner powder to flow into the fibers of the web material.
  • An oil pad 68 (Fig. 1) and 168 (Fig. 2) is provided to remove any excess powder which will cling to the upper fixing roller.
  • transfer roller 40 will be moved away from drum 29, and web feed roller 50 will be moved away from drive roller 59, to thereby disable the friction-drive applied to web 38 by rollers 50 and 59.
  • transfer roller 40 is moved a sufficient distance to carry the web into engagement with braking member 65 whereby web 38 is stopped immediately by the braking action.
  • a rotating plush roller 66 is provided in order to remove any toner powder which remains on the surface of plate 36 prior to the incremental areas thereof becoming charged again by ion-source unit 32.
  • This roller is po sitioned within a housing 67 for retaining the powder removed by the counterclockwise rotating action of the roller, from the xerographic drum plate 36.
  • FIG. 1 A comparison of the electrophotographic printers shown in Figs. 1 and 2 will reveal a similarity between many elements thereof.
  • those elements in the printer of Fig. 2 which are similar to corresponding elements in the printer shown in Fig. 1, will be identified by a series reference numeral corresponding to the reference numeral used in Fig. 1. That is, for example, the xerograph'ic drum of the printer shown in Fig. l, is identified by the reference numeral 29, and the xerographic drum of the printer shown in Fig. 2 is identified by the reference numeral 129.
  • record cards to be operated on are stacked in hopper 121, and are fed, one by one, each card cycle out of card hopper 121 to stacker 122. Successive pairs of feed rolls 123 and 124 cause the record cards to be advanced during successive card cycles past the optical projector apparatus 125.
  • Apparatus 125 includes a single light ray projector 126 for directing a band of light rays upon the constricted center of the aperture in member 127, to thereby effect a conventional light scanning operation whereby the image of the printed information on the record card is trans- 75 ferred to the surface of the xerographic drum 129.
  • Xerographic drum 129 is mounted on a shaft 131 which is driven by an electric motor 134 (see also Fig. in a counterclockwise direction.
  • the aforesaid drum includes an electrically conducting cylinder 135 and a light sensitive photoconductive insulating printing plate 136. This plate is carried by a sheet of any flexible metal or other conductive material 137 that enables its being flexed around and attached to the cylinder 135.
  • the xerographic drum With the feeding of record cards from hopper 121 to stacker 122, the xerographic drum is caused to rotate by shaft 31 at a speed which is correlated to the record card feed speed. As successive incremental areas of the light sensitive photoconductive plate 136 are moved past charging roller 170, the aforesaid plate is caused to have an electrical charge placed thereon.
  • the charging roller includes an inner-metallic portion 171 and an outer portion 172 of very resilient or yielding material having a high electrical resistance, as for example, a layer of soft conducting rubber. Inasmuch as this charging roller is substantially similar to the upper cylindrical member or roll used in the electrical printing apparatus described in Hooper Patent No. 2,520,504, reference may be had to this patent for more detailed information.
  • Transfer cylinder 175 includes end wheels 176 (see also Fig. 5) and 177, and a conductive roller 178.
  • the diameter of roller 178 is smaller than the diameters of end wheels 176 and 177 by an amount such that a gap of approximately 0.002 inches exists between plate 136 and web 138. In order that the web does not rub against the drum surface during print suppress time, it is necessary that the diameter of roller 178 is smaller than the diameter of the end wheels by an amount greater than twice the thickness of the web.
  • Roller 178 is rotatably mounted on cylinder shaft 179 in order that feeding of web 138 may be stopped during non-print periods even though the Xerographic drum is caused to continue rotating.
  • the wheels 176 and 177 are journaled and arranged in such a manner as to be electrically separated from shaft 179 which, as shown in Fig. 2, is used to supply electric power to conductive roller 178, and the cylinder shaft is biased in a direction towards drum 129 by conventional means so that the end wheels ride on the peripheral surface of the drum.
  • web 138 is fed from reel 156 past drag rollers 157, around rollers 160 and 178, between fixing rollers 158, feed rollers 150 and 159, to reel 161.
  • a rotating plush roller 166 In order to remove any toner powder which remains on the surface of plate 136, prior to the incremental areas thereof becoming charged again by charging cylinder 170, there is provided a rotating plush roller 166. This roller is positioned within a housing 167 for retaining the powder removed by the counterclockwise rotating action of. the roller, from the xerographic drum plate 136.
  • transfer roller 40 is connected to a source of positive potential, e. g., 1000 volts, via wire 70 and manually operated switch 71 and/ or cam contacts C1.
  • a source of positive potential e. g. 1000 volts
  • the insulating image plate 36 carried by the conductive supporting plate 37, is charged negatively, whereas the toner powder which produces the image by adherence to the plate 36, is charged positively by triboelectric action of the carrier material to which the electroscopic powder particles adhere until separated therefrom by the stronger attractive force of the negatively charged insulating image plate 36.
  • backing sheet 37 is electrically connected to grounded shaft 31
  • an effective condenser is obtained at the transfer station wherein backing sheet 37 and transfer roller 40 serve as plates thereof, and insulating plate 36 along with web 38 act as the dielectric thereof.
  • the aforementioned positive potential applied to transfer roller 40 is sulficient to cause an electric field to exist between the transfer roller 40 to backing plate 37.
  • This electrostatic field or potential gradient causes the powder adhering to plate 36 to transfer onto web 38, Whereafter the transferred powder on web 38 is fixed thereto by pressure rollers 58.
  • pressure rollers 58 In order to disable printing, i.
  • cam 62 is rotated so as to engage cam follower roller 48 which, in turn, causes arms 45, 46 and 49 to pivot in a counterclockwise direction.
  • cam follower roller 48 causes transfer roller 40 to be moved away from xerographic drum 29, and web feed roller 50 to be moved away from drive roller 59.
  • the resulting air space defined by the outer peripheries of plate 36 and transfer roller 40 is sufiicient to preclude a transfer of the powder from xerographic drum 29 onto web 38.
  • roller 50 disables the friction-drive that is applied to web 38 by rollers 50 and 59, and since the shifting of transfer roller 40 is of such a nature as to brake web 38 by means of braking member 65, web 38 is stopped immediately.
  • a suitable positive potential e. g., +2000 volts
  • roller 178 is electrified so that a resulting ion-stream transfers the toner powder adhering to plate 136 onto web 138, and the transfer of power is effective so long as cam contacts C2. are closed.
  • cam contacts C2 are caused to open.
  • web feed drive roller 159 is stopped so as to stop the feeding of web 138.
  • the drag load applied to web 138 by rollers 157, 158, 160, and 159 is sutficient to prevent any creep thereof.
  • roller 178 (see also Fig. 5) has a diameter which is smaller than that of end wheels 176 and 177, cylinder need not be shifted away from xerographic drum 129 during the periods when web 138 is not being moved.
  • a reverse image printer may be had simply by employing a reversal developer powder so that the charge on the powder image is reversed, and by connecting the transfer roller or cylinder to a voltage that is negative with respect to the Xerographic drum.
  • a suitable voltage may range from negative 1000 volts to negative 2000 volts.
  • the printed information which is to be transferred to the print receiving web is identified in the illustrated embodiments by reference numeral 30 (Fig. 3) and is typed, for instance, onthe source records.
  • the information to be transferred need not be in reversed order on the source records because the double reversal effected by the projection of the image onto plate 36 (Fig. 1), for example, and the subsequent transfer of the powdered image onto web 38, causes the information transferred to the web to be arranged in the same order as is the information on the source records.
  • xerographic drum 29 is shown to be operated by motor 34 through a speed reduction unit 80 having gears, or the like, therein, and which is also connected to drive unit 81 so as to cause cam 62 and cam contacts CI to operate in step with the drum.
  • the rotational speed of drum 2% and cam 62 is so correlated that whenever the image-portion 30a of the card provided with the information to be transferred, is disposed between drum 29 and transfer roller 40, cam 62 is in a position whereat springs 43 are free to move web 33 into simultaneous contact with plate 36 and transfer roller 40.
  • the information is thereby transferred from the xerographic drum to the paper strip 38.
  • transfer roller 49 will be shifted from an effective print position to a non-print position only after the desired information 3001 has been transferred to web 38.
  • the transfer roller will remain in the latter non-print position until a succeeding image 300 is moved into the transfer station. Inasmuch as feed roller 50 is moved away from drive roller 59 during nonprint time, web 38 is not advanced during this time.
  • cam 62 may be adjustable, or interchangeable with another cam so that the height of the information to be transferred to the web can be varied according to a predetermined requirement. It is apparent too that cam 62. may be provided with a number of cams, and in this event, a number of horizontal strips can be transferred to the web from several card sections.
  • the length of transfer roller 40 can be varied so as to be effective to transfer to web 38 only predetermined information. The arrangement may be such, for example, that the length of roller 4% corresponds to the vertical width of the information on the card.
  • roller 49 may be laterally adjustable so that the same presses onto xerographic drum 2 9 only when a certain part of the powder image is moved into the transfer station.
  • Transfer roller 4'0 may also be subdivided so that a number of vertical portions are printed from a single card section.
  • any printed information from a source record can be transferred to a print receiving material by merely varying the two transfer control members; namely the cam 62 and the transfer roller 40.
  • printing at the transfer station may be disabled by simply shifting transfer roller 40 away from xerographic drum 29.
  • This type of operation may be had by opening manually operated switch 71 and permitting the electric power that is applied to transfer roller 40 to be under control of cam contacts C1.
  • the cam contacts may be timed so that a circuit is completed to roller whenever the said roller is shifted to a printing position, and opened whenever roller 40 is shifted to a non-printing position.
  • Xerographic drum 129 is operated by motor 134 through a suitable gear unit 180 which is also connected to a driven unit 181 for operating paper feed roller 159 and cam contacts C2.
  • Unit 181 includes a gear sector for operating roller 159 intermittently so that roller 159 is operated to advance web 138 whenever the image lfitla to be transferred is moved to the printing, or transfer, station.
  • Cam contacts C2 are timed to be in step with the movement of feed roller 159; i. e., the contacts are closed so as to apply a positive potential to conductive roller 178 during the time that image 130a is at the transfer station, and open during all other periods.
  • the diameter of roller 173 is smaller than that of end wheels 176 and 177 and, as a result thereof, web 138 may be stopped during non-print time even though Xerographic drum 12f continues to rotate. That is, there is a sufficient clearance between the outer surface of web 138 and the outer surface of plate 136 so that either the web or the plate may be stopped during a movement of the other Without creating a rubbing action therebetween.
  • an electric printer comprising a rotatable printing drum having an inner electrically conducting member and an outer dielectric surface portion adapted to support transferable images thereon for transfer at a printing zone to a Web, a conductive cylinder for supporting the web in a position at the printing zone intermediate said printing drum and said cylinder, a source of electric power, electric circuit means for connecting said conducting member and said cylinder to said power source, means for rotating said printing drum, means for moving said web at a lineal speed correlated to the peripheral speed of said printing drum, and circuit interrupter means operable synchronously with said drum rotating means for governing said electric circuit means so that electric power is applied to said member and said cylinder as said transferable images are moved through the printing zone, to thereby effect a transfer of said images from said printing drum to said web.
  • an electrophotographic printer comprising a printing member, shiftable means normally at: one limit of movement nearest said printing member for applying an electric force at a printing zone, means for moving said printing member relative to said electric force applying means, means for feeding a print receiving material between said member and said electric force applying means in a timed relation to the movement of said member, and means operable synchronously with said printing member moving means for shifting said electric force applying means from said one limit whereat said electric force applying means is effective to cause printing, to another limit of movement away from said printing member whereat said electric force applying means is ineffective to cause printing.
  • a printer of the class described having a printing member, means including a shiftable conductive cylinder for producing a print effecting electric force at a printing Zone, means for moving said printing member relative to said cylinder in a direction substantially parallel to the axis of said cylinder, means for feeding a print receiving material between said member and said cylinder in a timed relation to the movement of said member, and means operable synchronously with said member moving means for normally maintaining said conductive cylinder in pressure engagement with said web and said printing member and for shifting said conductive cylinder away from, said printing member to thereby effect selective printing at the printing zone.
  • an electrophotographic printer having a rotatable printing drum including an inner electrically conducting member and an outer dielectric surface portion adapted to support electrically charged powder images thereon for transfer to a web, a shiftable conductive cylinder for supporting the web between opposing surfaces of said cylinder and said drum, a source of electric energy, electric circuit means for connecting said conducting member and said cylinder to said source, means for continuously rotating said drum, whereby said web is fed in a path adjacent to a portion of the periphery of said drum and at a lineal speed correlated to the peripheral speed of said drum, a stationary web braking member, and means operable synchronously with said drum rotating means for shifting said cylinder from a printing position whereat said web engages said drum and said cylinder simultaneously, to a non-printing position whereat said web engages said braking member and said cylinder.
  • the combination of apparatus at a printing zone for transferring electrically charged powder images to a web comprising an electrostatically charged printing drum adapted to support said charged powder images thereon, radially shiftable means for normally supporting said web in contact with said printing drum at one limit of movement of said shiftable means and out of contact with said drum at the other limit of movement thereof, said web supporting means including a rotatable cylinder having a surface layer of conducting resilient material for producing by electric current an electrostatic field of force at the region of contact of said web and said printing drum, said lines of force thereof acting in a direction to transfer said charged powder images from said drum to said web, means for rotating said printing drum whereby said web is normally moved at a lineal speed correlated to the peripheral speed of said drum, and means for shifting said web supporting means radially with respect to the axis of said drum from said one limit of movement to said other limit of movement so that the strength of said electrostatic field of force at the printing zone is changed respectively from one effective to cause printing onto said web moving with said drum and to
  • means including a conductive cylinder having a resistivity of at least ohms per cubic centimeter for producing an electric force at a printing zone, means for moving said printing member relative to said cylinder in a direction substantially parallel to the axis of said cylinder, means for feeding a print receiving material between opposing surfaces of said member and said cylinder in a timed relation to the surface movement of said member, and means operable synchronously with said member moving means for shifting said conductive cylinder towards and away from said printing member to thereby control printing at the printing zone.
  • An electrophotographic printer transfer station comprising a photoconductive member adapted to support charged powder images thereon, an electrically conducting transfer roller, means for feeding a powder receiving web between opposing surfaces of said photoconductive member and said transfer roller, yielding means urging said photoconductive member and said transfer roller into engagement, and means associated with said web feeding means to cause said yielding means to be out of engagement with said member when the advancing movement of said Web is stopped.
  • Apparatus for transferring select ones of a plurality of electrically charged powder images to the surface of a sheet material comprising a printing member adapted to support a plurality of said charged powder images arranged successively thereon, means including a conductive rotatable cylinder for applying an electric force at a printing zone, means for normally feeding said sheet material through said printing zone defined by the opposing surfaces of said printing member and said conductive cylinder so that said cylinder is rotated thereby, drive means for moving said printing member in a direction substantially parallel to the axis of said conductive cyl inder and in a timed relation to the feeding movement of said sheet material, means for controlling said electric field of force from one limit whereby said charged powder images may be transferred from said printing member to said sheet material, to another limit whereat said charged powder images may not be transferred from said printing member to said sheet material, and means effective concurrently and conjointly with said electric force applying means to render said sheet material feeding means disabled when the strength of the electric field of force is altered to said another limit.
  • a printing member means including .a conductive cylinder for applying an electric force at a printing zone, means for moving said printing member relative to said cylinder in a direction substantially parallel to the axis of said cylinder, means for feeding a print receiving material through said printing zone defined by opposing surfaces of said member and said cylinder in a timed relation to the movement of said member, means operable simultaneously with said member moving means for controlling said electric force applying means so that the electric force at said printing zone is effective for printing, and means including said cylinder for preventing feeding of said print receiving material when the electric force at said printing zone is ineifective for printing.
  • a transfer apparatus comprising a web idler roller; a conductive cylinder; a pivotally mounted member adapted to support said web idler roller and said conductive cylinder; a stationary web braking element; resilient means (a) for normally maintaining said web idler roller in a web feeding position relative said web feeding roller whereby said web is in pressure contact with both of said rollers so that said web is advanced through a printing zone defined by the opposing surfaces of said printing drum and said cylinder, and through a web braking zone defined by the opposing surfaces of said cylinder and said stationary braking element, and (b) for normally maintaining said cylinder in a print efiecting position relative said printing drum whereby said web is in pressure contact with said printing drum and said cylinder; and means for pivoting said pivotally mounted member so that said web idler roller is moved relative said web feeding roller and out of the web feeding position, and said cylinder is moved concurrently therewith

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Theoretical Computer Science (AREA)
  • Combination Of More Than One Step In Electrophotography (AREA)
  • Feeding Of Articles By Means Other Than Belts Or Rollers (AREA)
  • Electrostatic Charge, Transfer And Separation In Electrography (AREA)
US419314A 1954-03-29 1954-03-29 Electrophotographic printing machine Expired - Lifetime US2807233A (en)

Priority Applications (11)

Application Number Priority Date Filing Date Title
BE536878D BE536878A (xx) 1954-03-29
NL195972D NL195972A (xx) 1954-03-29
BE536877D BE536877A (xx) 1954-03-29
US419392A US2859673A (en) 1954-03-29 1954-03-29 Electrophotographic printer
US419314A US2807233A (en) 1954-03-29 1954-03-29 Electrophotographic printing machine
US419702A US2909971A (en) 1954-03-29 1954-03-30 Printing machine
FR1141378D FR1141378A (fr) 1954-03-29 1955-03-25 Dispositif d'impression xérographique à ruban épais
GB8738/55A GB766426A (en) 1954-03-29 1955-03-25 Electrophotographic printing machine
GB8737/55A GB768020A (en) 1954-03-29 1955-03-25 Printing machine
CH333951D CH333951A (fr) 1954-03-29 1955-03-28 Dispositif d'impression xérographique
CH333952D CH333952A (fr) 1954-03-29 1955-03-28 Dispositif d'impression xérographique

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US419392A US2859673A (en) 1954-03-29 1954-03-29 Electrophotographic printer
US419314A US2807233A (en) 1954-03-29 1954-03-29 Electrophotographic printing machine

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US2807233A true US2807233A (en) 1957-09-24

Family

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US419392A Expired - Lifetime US2859673A (en) 1954-03-29 1954-03-29 Electrophotographic printer
US419314A Expired - Lifetime US2807233A (en) 1954-03-29 1954-03-29 Electrophotographic printing machine

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US419392A Expired - Lifetime US2859673A (en) 1954-03-29 1954-03-29 Electrophotographic printer

Country Status (6)

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US (2) US2859673A (xx)
BE (2) BE536877A (xx)
CH (2) CH333952A (xx)
FR (1) FR1141378A (xx)
GB (2) GB768020A (xx)
NL (1) NL195972A (xx)

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US2907254A (en) * 1955-12-21 1959-10-06 Ibm Record card controlled electrographic printer
US2919191A (en) * 1954-12-27 1959-12-29 Haloid Xerox Inc Xerographic transfer method
US2927516A (en) * 1955-12-21 1960-03-08 Ibm Record card controlled electro-graphic printer
US2934650A (en) * 1957-04-10 1960-04-26 Haloid Xerox Inc Charging apparatus
US2940847A (en) * 1957-07-03 1960-06-14 None i red
US2951443A (en) * 1956-12-27 1960-09-06 Haloid Xerox Inc Image reproduction
US3043684A (en) * 1955-01-26 1962-07-10 Gen Dynamics Corp Electrostatic printing
US3045644A (en) * 1957-06-06 1962-07-24 Xerox Corp Two-color electrostatic printing apparatus
US3063859A (en) * 1955-03-01 1962-11-13 Xerox Corp Method and apparatus for transferring images from xerographic to metallic plates
US3071070A (en) * 1955-03-01 1963-01-01 Xerox Corp Method and apparatus for transferring images from xerographic to metallic plates
US3132050A (en) * 1960-04-04 1964-05-05 Xerox Corp Xerographic transfer apparatus
US3198648A (en) * 1961-11-30 1965-08-03 Burroughs Corp Electrostatic recording method
US3267840A (en) * 1962-11-27 1966-08-23 Tokyo Shibaura Electric Co Powder image transfer system
US3280741A (en) * 1958-12-31 1966-10-25 Burroughs Corp Electrostatic recording
DE1234430B (de) * 1961-02-07 1967-02-16 Clary Corp Druckwerk
US3306198A (en) * 1963-12-04 1967-02-28 Continental Can Co Electrostatic printing process
US3363552A (en) * 1965-10-20 1968-01-16 Continental Can Co Methods and apparatus for minimizing screen patterns in xerography, electrostatic screen process and other forms of printing
DE1772898A1 (de) * 1967-12-29 1971-06-16 Addressograph Multigraph Verfahren und Vorrichtung zur Fixierung von Tonern
US3628504A (en) * 1970-03-23 1971-12-21 Singer Co Adjustable mounting device for electrostatic copier developer magazine
US3633543A (en) * 1969-12-05 1972-01-11 Xerox Corp Biased electrode transfer apparatus
US3640249A (en) * 1969-10-29 1972-02-08 Xerox Corp Transfer apparatus
US3751156A (en) * 1971-10-21 1973-08-07 Agfa Gevaert Ag Electrostatic copying apparatus with means for preventing contamination of transfer material
JPS4990946A (xx) * 1972-12-11 1974-08-30
US3866573A (en) * 1971-10-21 1975-02-18 Agfa Gevaert Ag Electrostatic copying apparatus
JPS5034832A (xx) * 1973-07-31 1975-04-03
US3942888A (en) * 1975-02-06 1976-03-09 Xerox Corporation Stepped transfer roller
US3950168A (en) * 1973-02-26 1976-04-13 Xerox Corporation Fixing powder images
US4106868A (en) * 1975-11-05 1978-08-15 Oce-Van Der Grinten N.V. Electrographic copying apparatus with surface-to-surface image transfers
JPS5533151A (en) * 1978-08-30 1980-03-08 Minolta Camera Co Ltd Line-jump copying apparatus in electrophotography
JPS55105446U (xx) * 1980-02-21 1980-07-23
US4309803A (en) * 1980-09-29 1982-01-12 Xerox Corporation Low cost foam roll for electrostatographic reproduction machine
US4380196A (en) * 1976-04-26 1983-04-19 Mita Industrial Company Limited Plate for lithography or offset printing
US4477176A (en) * 1983-12-27 1984-10-16 Eastman Kodak Company Apparatus for producing multiple image simplex and duplex copies in a single pass
US4496233A (en) * 1983-04-28 1985-01-29 Xerox Corporation Electrostatic reproducing machine
US4497567A (en) * 1983-04-28 1985-02-05 Xerox Corporation Toner transferring method and apparatus
US4998143A (en) * 1988-09-20 1991-03-05 Hitachi, Ltd. Electrophotographic image transfer member, electrophotographic image transfer device and electrophotographic recording apparatus
US5011739A (en) * 1989-10-02 1991-04-30 Eastman Kodak Company Moisture stable biasable transfer members and method for making same
US5070366A (en) * 1989-03-10 1991-12-03 Canon Kabushiki Kaisha Image forming apparatus featuring a constant contact-pressure drive
US5156915A (en) * 1991-11-26 1992-10-20 Eastman Kodak Company Moisture stable polyurethane biasable members
US5168313A (en) * 1988-04-28 1992-12-01 Kabushiki Kaisha Toshiba Toner image transfer method and device for electrophotographic printing apparatus
US5168290A (en) * 1990-02-06 1992-12-01 Canon Kabushiki Kaisha Image forming apparatus having recording material carrying means
US5212032A (en) * 1991-11-26 1993-05-18 Eastman Kodak Company Moisture stable polyurethane biasable transfer members
US5217838A (en) * 1991-11-26 1993-06-08 Eastman Kodak Company Moisture stable biasable transfer members
US5247335A (en) * 1992-08-24 1993-09-21 Xerox Corporation Developed image transfer assist apparatus having a cam mechanism
US5250357A (en) * 1991-11-26 1993-10-05 Eastman Kodak Company Moisture stable elastomeric polyurethane biasable transfer members
EP0690360A2 (en) 1994-06-30 1996-01-03 Eastman Kodak Company Polyurethane biasable transfer members
EP0690359A2 (en) 1994-06-30 1996-01-03 Eastman Kodak Company Polyurethane biasable transfer members having improved moisture stability
US5506745A (en) * 1994-08-05 1996-04-09 Xerox Corporation Hollow conformable charge roll
US5536352A (en) * 1994-11-14 1996-07-16 Eastman Kodak Company Methods of making centrifugally cast parts
US5643706A (en) * 1995-11-30 1997-07-01 Xerox Corporation Process for preparing electroconductive members
US5677022A (en) * 1994-11-14 1997-10-14 Eastman Kodak Company Electrostatographic roller mask
US5702852A (en) * 1995-08-31 1997-12-30 Eastman Kodak Company Multi-color method of toner transfer using non-marking toner and high pigment marking toner
US5729810A (en) * 1993-01-22 1998-03-17 Xerox Corporation Overcoated transfer roller for transferring developed images from one surface to another
US5794111A (en) * 1995-12-14 1998-08-11 Eastman Kodak Company Apparatus and method of transfering toner using non-marking toner and marking toner
US5849399A (en) * 1996-04-19 1998-12-15 Xerox Corporation Bias transfer members with fluorinated carbon filled fluoroelastomer outer layer
US6548154B1 (en) 2000-11-28 2003-04-15 Xerox Corporation Electrical charge relaxable wear resistant coating for bias charging or transfer member
US6584296B1 (en) 2001-11-30 2003-06-24 Xerox Corporation Electro-mechanical roll with core and segments
US6606477B2 (en) 2002-01-16 2003-08-12 Xerox Corporation Method to control pre- and post-nip fields for transfer
US20050286934A1 (en) * 2004-06-25 2005-12-29 Xerox Corporation Biased charge roller with embedded electrodes with post-nip breakdown to enable improved charge uniformity
US7067027B2 (en) 2001-11-30 2006-06-27 Xerox Corporation Method of making an electro-mechanical roll

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US2956487A (en) * 1955-03-23 1960-10-18 Rca Corp Electrostatic printing
US3009402A (en) * 1957-06-03 1961-11-21 Xerox Corp Xerographic processing apparatus
US3040322A (en) * 1958-08-15 1962-06-19 Baldwin Piano Co Device and method for producing code members
US3052155A (en) * 1958-09-11 1962-09-04 Bruning Charles Co Inc Apparatus for exposing light sensitive sheets and/or webs
US3062094A (en) * 1958-12-29 1962-11-06 Xerox Corp Electrophotographic copying apparatus
US3023670A (en) * 1959-08-31 1962-03-06 Romero Cora Lora Automatic symbol reproducing device
US3051044A (en) * 1959-09-09 1962-08-28 Gen Dynamics Corp Recording and projection system
US3075493A (en) * 1959-09-14 1963-01-29 Xerox Corp Xerographic apparatus with web cutting means
US3100426A (en) * 1960-04-26 1963-08-13 Edward K Kaprelian Electrophotographic printers
US3186838A (en) * 1960-12-27 1965-06-01 Xerox Corp Xerographic plate cleaning method utilizing the relative movement of a cleaning web
JPS5113079Y1 (xx) * 1967-03-25 1976-04-08
US3649126A (en) * 1967-09-20 1972-03-14 Ricoh Kk Slit exposure device for a reproduction apparatus
US3854975A (en) * 1971-06-30 1974-12-17 Addressograph Multigraph Pressure fixing of toners
US3847119A (en) * 1972-03-27 1974-11-12 Xerox Corp Transfer roller assembly
JPS5012738U (xx) * 1973-05-31 1975-02-10
US3975715A (en) * 1973-10-25 1976-08-17 Xerox Corporation Scanning and selection methods and apparatus therefor
JPS538146A (en) * 1976-07-12 1978-01-25 Canon Inc Transfer mechanism
JPS5317340A (en) * 1976-07-30 1978-02-17 Canon Inc Recording device

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US2357809A (en) * 1940-11-16 1944-09-12 Chester F Carlson Electrophotographic apparatus
US2633796A (en) * 1944-04-05 1953-04-07 Hoe & Co R Printing means using electric fields
US2624652A (en) * 1944-10-11 1953-01-06 Chester F Carlson Graphic recording
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Cited By (66)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2919191A (en) * 1954-12-27 1959-12-29 Haloid Xerox Inc Xerographic transfer method
US3043684A (en) * 1955-01-26 1962-07-10 Gen Dynamics Corp Electrostatic printing
US3063859A (en) * 1955-03-01 1962-11-13 Xerox Corp Method and apparatus for transferring images from xerographic to metallic plates
US3071070A (en) * 1955-03-01 1963-01-01 Xerox Corp Method and apparatus for transferring images from xerographic to metallic plates
US2927516A (en) * 1955-12-21 1960-03-08 Ibm Record card controlled electro-graphic printer
US2907254A (en) * 1955-12-21 1959-10-06 Ibm Record card controlled electrographic printer
US2951443A (en) * 1956-12-27 1960-09-06 Haloid Xerox Inc Image reproduction
US2934650A (en) * 1957-04-10 1960-04-26 Haloid Xerox Inc Charging apparatus
US3045644A (en) * 1957-06-06 1962-07-24 Xerox Corp Two-color electrostatic printing apparatus
US2940847A (en) * 1957-07-03 1960-06-14 None i red
US3280741A (en) * 1958-12-31 1966-10-25 Burroughs Corp Electrostatic recording
US3132050A (en) * 1960-04-04 1964-05-05 Xerox Corp Xerographic transfer apparatus
DE1234430B (de) * 1961-02-07 1967-02-16 Clary Corp Druckwerk
US3198648A (en) * 1961-11-30 1965-08-03 Burroughs Corp Electrostatic recording method
US3267840A (en) * 1962-11-27 1966-08-23 Tokyo Shibaura Electric Co Powder image transfer system
US3306198A (en) * 1963-12-04 1967-02-28 Continental Can Co Electrostatic printing process
US3363552A (en) * 1965-10-20 1968-01-16 Continental Can Co Methods and apparatus for minimizing screen patterns in xerography, electrostatic screen process and other forms of printing
DE1772898A1 (de) * 1967-12-29 1971-06-16 Addressograph Multigraph Verfahren und Vorrichtung zur Fixierung von Tonern
US3640249A (en) * 1969-10-29 1972-02-08 Xerox Corp Transfer apparatus
US3633543A (en) * 1969-12-05 1972-01-11 Xerox Corp Biased electrode transfer apparatus
US3628504A (en) * 1970-03-23 1971-12-21 Singer Co Adjustable mounting device for electrostatic copier developer magazine
US3751156A (en) * 1971-10-21 1973-08-07 Agfa Gevaert Ag Electrostatic copying apparatus with means for preventing contamination of transfer material
US3866573A (en) * 1971-10-21 1975-02-18 Agfa Gevaert Ag Electrostatic copying apparatus
JPS4990946A (xx) * 1972-12-11 1974-08-30
US3950168A (en) * 1973-02-26 1976-04-13 Xerox Corporation Fixing powder images
JPS5034832A (xx) * 1973-07-31 1975-04-03
US3942888A (en) * 1975-02-06 1976-03-09 Xerox Corporation Stepped transfer roller
US4106868A (en) * 1975-11-05 1978-08-15 Oce-Van Der Grinten N.V. Electrographic copying apparatus with surface-to-surface image transfers
US4380196A (en) * 1976-04-26 1983-04-19 Mita Industrial Company Limited Plate for lithography or offset printing
JPS5533151A (en) * 1978-08-30 1980-03-08 Minolta Camera Co Ltd Line-jump copying apparatus in electrophotography
JPS5943575Y2 (ja) * 1980-02-21 1984-12-25 富士通株式会社 電子写真プリンタ
JPS55105446U (xx) * 1980-02-21 1980-07-23
US4309803A (en) * 1980-09-29 1982-01-12 Xerox Corporation Low cost foam roll for electrostatographic reproduction machine
US4496233A (en) * 1983-04-28 1985-01-29 Xerox Corporation Electrostatic reproducing machine
US4497567A (en) * 1983-04-28 1985-02-05 Xerox Corporation Toner transferring method and apparatus
US4477176A (en) * 1983-12-27 1984-10-16 Eastman Kodak Company Apparatus for producing multiple image simplex and duplex copies in a single pass
US5168313A (en) * 1988-04-28 1992-12-01 Kabushiki Kaisha Toshiba Toner image transfer method and device for electrophotographic printing apparatus
US4998143A (en) * 1988-09-20 1991-03-05 Hitachi, Ltd. Electrophotographic image transfer member, electrophotographic image transfer device and electrophotographic recording apparatus
US5070366A (en) * 1989-03-10 1991-12-03 Canon Kabushiki Kaisha Image forming apparatus featuring a constant contact-pressure drive
US5011739A (en) * 1989-10-02 1991-04-30 Eastman Kodak Company Moisture stable biasable transfer members and method for making same
US5168290A (en) * 1990-02-06 1992-12-01 Canon Kabushiki Kaisha Image forming apparatus having recording material carrying means
US5156915A (en) * 1991-11-26 1992-10-20 Eastman Kodak Company Moisture stable polyurethane biasable members
US5250357A (en) * 1991-11-26 1993-10-05 Eastman Kodak Company Moisture stable elastomeric polyurethane biasable transfer members
US5212032A (en) * 1991-11-26 1993-05-18 Eastman Kodak Company Moisture stable polyurethane biasable transfer members
US5217838A (en) * 1991-11-26 1993-06-08 Eastman Kodak Company Moisture stable biasable transfer members
EP0584928A3 (en) * 1992-08-24 1995-03-22 Xerox Corp Auxiliary transfer device for developed images with a cam mechanism.
EP0584928A2 (en) * 1992-08-24 1994-03-02 Xerox Corporation Developed image transfer assist apparatus having a cam mechanism
US5247335A (en) * 1992-08-24 1993-09-21 Xerox Corporation Developed image transfer assist apparatus having a cam mechanism
US5729810A (en) * 1993-01-22 1998-03-17 Xerox Corporation Overcoated transfer roller for transferring developed images from one surface to another
EP0690360A2 (en) 1994-06-30 1996-01-03 Eastman Kodak Company Polyurethane biasable transfer members
EP0690359A2 (en) 1994-06-30 1996-01-03 Eastman Kodak Company Polyurethane biasable transfer members having improved moisture stability
US5541001A (en) * 1994-06-30 1996-07-30 Eastman Kodak Company Polyurethane biasable transfer members having improved moisture stability
US5554474A (en) * 1994-06-30 1996-09-10 Eastman Kodak Company Conductive substrate bearing a elastomeric polyurethane coating containing a conductivity control agent
US5506745A (en) * 1994-08-05 1996-04-09 Xerox Corporation Hollow conformable charge roll
US5536352A (en) * 1994-11-14 1996-07-16 Eastman Kodak Company Methods of making centrifugally cast parts
US5677022A (en) * 1994-11-14 1997-10-14 Eastman Kodak Company Electrostatographic roller mask
US5702852A (en) * 1995-08-31 1997-12-30 Eastman Kodak Company Multi-color method of toner transfer using non-marking toner and high pigment marking toner
US5643706A (en) * 1995-11-30 1997-07-01 Xerox Corporation Process for preparing electroconductive members
US5794111A (en) * 1995-12-14 1998-08-11 Eastman Kodak Company Apparatus and method of transfering toner using non-marking toner and marking toner
US5849399A (en) * 1996-04-19 1998-12-15 Xerox Corporation Bias transfer members with fluorinated carbon filled fluoroelastomer outer layer
US6548154B1 (en) 2000-11-28 2003-04-15 Xerox Corporation Electrical charge relaxable wear resistant coating for bias charging or transfer member
US6584296B1 (en) 2001-11-30 2003-06-24 Xerox Corporation Electro-mechanical roll with core and segments
US7067027B2 (en) 2001-11-30 2006-06-27 Xerox Corporation Method of making an electro-mechanical roll
US6606477B2 (en) 2002-01-16 2003-08-12 Xerox Corporation Method to control pre- and post-nip fields for transfer
US20050286934A1 (en) * 2004-06-25 2005-12-29 Xerox Corporation Biased charge roller with embedded electrodes with post-nip breakdown to enable improved charge uniformity
US7177572B2 (en) 2004-06-25 2007-02-13 Xerox Corporation Biased charge roller with embedded electrodes with post-nip breakdown to enable improved charge uniformity

Also Published As

Publication number Publication date
GB768020A (en) 1957-02-13
BE536877A (xx)
CH333951A (fr) 1958-11-15
FR1141378A (fr) 1957-09-02
US2859673A (en) 1958-11-11
CH333952A (fr) 1958-11-15
BE536878A (xx)
NL195972A (xx)
GB766426A (en) 1957-01-23

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