US3099856A

US3099856A - Web cleaner apparatus

Info

Publication number: US3099856A
Application number: US162823A
Authority: US
Inventors: Roger H Eichorn; John A Strommer
Original assignee: Xerox Corp
Current assignee: Xerox Corp
Priority date: 1961-12-28
Filing date: 1961-12-28
Publication date: 1963-08-06
Anticipated expiration: 1980-08-06

Description

1963 R. H. EICHORN ETAL 3,099,856

WEB CLEANER APPARATUS 3 Sheets-Sheet 1 Filed Dec. 28, 1961 IN V EN TOR.

vv, R 5 N N RM R m 0 mm H 15/ R EN 6H w 00 RJ 1963 R. H. EICHORN ETAL 3,099,856

WEB CLEANER APPARATUS 3 Sheets-Sheet 2 Filed Dec. 28. 1961 INVENTOR.

ROGER H. EICHORN JOHN A. STROMMER A TTORNEV 1963 R. H. EICHORN ETAL- 3,099,856

WEB CLEANER APPARATUS 3 Sheets-Sheet 5 Filed Dec. 28. 1961 m DFm ww Nov 8 \N A mww INVENTOR. ROGER H.

EICHORN (7JOHN A. STROMMEP.

finite This invention relates to xerography and, particu arly, to apparatus for cleaning the surface of a xerographic plate from which a powder image has been transferred. More specifically, the invention rel-ates to apparatus for removing any residual powder remaining on a xerographic plate after transfer of a powder image from the xerographic plate to a support surface.

In the process of xerography, for example, as disclosed in Carlson Patent 2,297,691, issued October 6, 1942, a xerographic plate comprising a layer of photoconductive insulating material on a conductive backing is given a uniform electric charge over its surface and is then exposed to the subject matter to be reproduced, usually by conventional projection techniques. This exposure discharges the plate are-as in accordance with the radiation intensity that reaches them and thereby creates an electrostatic latent image on or in the photoconductive layer. Development of the latent image is effected with an electrostatically charged, finely divided material, such as an eleotroscopic powder, that is brought into surface contact with the photoconductive layer and is held thereon electrostatically in a pattern corresponding to the electrostatic latent rim-age. Thereafter, the developed xerographic powder image is usually transferred to a support surface to which it may be fixed by any suitable means.

The cycle above described is typical for forming xerographic reproductions on a support surface and may be carried out manually, or automatically, as is done with mechanized equipment which performs the cycle repeatedly. In either case, however, after transfer of a powder image from a plate to a support surface, there usually remains on the plate a residual of unremoved developing powder usually in image configuration and referred to in the art as a residual powder image. Before the plate can be reused for a subsequent cycle it is necessary to remove the residual image to prevent ghost images from subsequently reproducing.

In automatic xerographic equipment it is common to employ a xerographic plate in the form of a cylindrical drum which is continuously rotated through the cycle of sequential operations including charging, exposure developing and transfer during which copy is reproduced on a support surface and after which the plate is cleaned before repeating the cycle.

It is usual to charge the plate with corona of positive polarity by means of a corona generating device of the type disclosed in Walkup Patent 2,777,957, which is connected to a suitable source of high potential. Development of an electrostatic latent image forms a powder image on the plate which is electrostatically transferred to a support surface by means of a corona generating device such as mentioned above. In the automatic type of equipment employing a rotating drum, a support surface to which a powder image is to be transferred is moved through the equipment at the same rate as the periphery of the drum and contacts the drum at the transfer position htatcs Patent ice interposed between the drum surface and the corona generating device. Transfer is effected by the corona generating device which imparts an electrostatic charge to attract the powder image from the drum to the support surface. The polarity of charge required to effect image transfer is dependent upon the visual form of the original copy relative to the reproduction and the electroscopic characteristics of the developing material employed to effect development. As for example, where a positive reproduction is to be made of a positive original, it is usual to employ a developing material which is triboelectrically charged to negative polarity, and after formation of a powder image, positive polarity corona is used to effect transfer of the support surface. In contrast, to produce a positive reproduction from a negative original, it is usual to employ a positively charged developing material which is repelled by the non-image areas on the plate to the discharged image areas thereon and negative polarity corona is employed to effect transfer.

In the positive-to-positive type of reproduction described above the residual of developer is to tightly retained to the plates photoconductive surface, by a phenomenon that is not fully understood but believed caused by an electrical charge, that it prevents complete transfer Of the powder to the support surface particularly in the image areas, and it is therefore necessary to substantially neutralize this charge by means of a corona generating device before effecting removal of the powder residue by means of a cleaning apparatus.

Heretofore, typical plate cleaning means employed one or more rotating brushes which after substantial neutralization of charge referred to above, brushed residual powder from the plate and a stream of air exhausted the removed powder th-rough a filtering system. Whereas the brush method of powder removal produced satisfactory results, it has been discovered that equally good results are attained by apparatus constructed in accordance with the present invention and at far less cost of manufacture and operation.

A typical brush cleaning apparatus is disclosed in Walkup Patent 2,832,977. In Walkup, reference is made to the types of brush materials which have proven most satisfactory for plate cleaning. In general, and desirably, any cleaning material must be sufliciently soft so that it does not abrade the insulated plate surface and at the same time be sufficiently firm to remove the residual powder image without becoming matted or clogged after re peated use. Other factors, such as the triboelectric characteristics of the material also enter into the desirability of its selection and for brush cleaning in Xerography animal furs, such as New Zealand rabbit, have shown themselves to be preferred. However, brushes of the animal for type are expensive and at best have a limited cleaning life of approximately 35-40 hours when used, for example, to clean a 15 /2 inch diameter drum rotating at about 5 r.p.m. before they ultimately become clogged and operate at decreased efficiency. In addition, with brush cleaning it is necessary to employ a vacuum and filtering system in conjunction therewith for exhausting the removed powder.

In the present invention, the need for a vacuum'and filtering system are eliminated and instead of an expensive brush element, a web of low cost expendable fibrous material, as described below, is presented to the xerographic plate with a rubbing action to effect removal of the residual image.

In copending application, Serial No. 110,281, filed December 27, 1960, in the name of Grafl et al., there is disclosed an improved method and apparatus for cleaning residual powder from a xerographic plate. As disclosed in this application, removal of residual powder is effected by rubbing against the drum surface, to be cleaned, a web of fibrous material such as, for example paper toweling, cheesecloth, flannel, and cotton fiber impregnated with a resin of urea formaldehyde. These inexpensive and disposable webs of fibrous material are advanced into pressure and rubbing or wiping contact with the xerographic plate and are gradually and continually advanced to present a clean surface to the plate whereby complete removal of residual powder from the plate is effected.

The principal object of the invention is to improve web cleaning aparatus for removing residual powder images from a xerographic plate.

Another object of the invention is to improve web cleaning apparatus for cleaning a xerographic plate in a manner to increase the efliciency of the cleaning operation and to decrease the manufacturing and operating costs of such apparatus.

For a better understanding of the invention as well as other objects and further features thereof, reference is had to the following detailed description of the invention to be read in connection with the accompanying drawings, wherein:

FIG. 1 illustrates schematically a xerographic reproducing apparatus employing a preferred embodiment of the web cleaner apparatus of the invention;

FIG. 2 is a left hand perspective view from the back of the machine of the web cleaner apparatus of the invention in operative position in the xerographic reproducing apparatus;

FIG. 3 is a sectional view of the Web cleaning roll drive mechanism for the web cleaner of the invention;

FIG. 4 is an enlarged sectional view of the clutch mechanism for driving the take-up roll of the web cleaner apparatus; and,

FIG. 5 is a schematic view of a portion of the xerographic reproducing apparatus of FIG. 1, but with the web cleaning roll positioned out of engagement with the Xerographic drum.

GENERAL As shown, the Xerographic apparatus comprises a Xerograph-ic plate including a photoconductive layer or lightreceiving surface on a conductive backing and formed in the shape of a drum, generally designated by numeral 20, which is journaled in a frame to rotate in the direction indicated by the arrow to cause the drum surface sequentially to pass a plurality of xerognaphic processing stations.

For the purpose of the present disclosure, the several xerographic processing stations in the path of movement of the drum surface may be described functionally, as

. follows:

A charging station, at which a uniform electrostatic charge is deposited on the photoconductive layer of the vxerographic drum;

An exposure station, at which a light or radiation pattern of copy to be reproduced is projected onto the drum surface to dissipate the drum charge in the exposed areas thereof and thereby form a =latent electrostatic image of the copy to be reproduced;

A developing station, at which a xerographic developing material including toner particles having an electrostatic charge opposite to that of the electrostatic latent image are cascaded over the drum surface, whereby the toner particles adhere to the electrostatic latent image to form a xerographic powder image in the configuration I of the copy to be reproduced;

A transfer station, at which the Xerographic powder image is electrostatically transferred from the drum surface to a transfer material or support surface; and

A drum cleaning station, at which the drum surface is first charged and then brushed or wiped to remove residual toner particles remaining thereon after image transfer, and at which the drum surface is exposed to a relatively bright-light source to effect substantially complete discharge of any residual electrostatic charge remaining thereon.

The charging station is preferably located as indicated by reference character A in the schematic illustration of the apparatus. In general, the charging apparatus or corona charging device 21 includes a corona discharge array of one or more discharge electrodes that extend transversely across the drum surface and are energized from a high potential source and are substantially enclosed within a shielding member.

Next subsequent thereto in the path of motion of the xerographic drum is an exposure station B. This exposure station may be one of a number of types of mechanisms or members such as desirably an optical scanning or projection system, or the like, designed to project a line copy image onto the surface of the photoconductive xerographic drum from a suitable original.

The optical scanning or projection assembly consists of a copyboard in the shape of a drum, hereinafter referred to as copy drum 30, which is adapted to support copy to be reproduced and arranged to rotate in light-projection relation to the moving light-receiving surface of the xerographic plate. Uniform lighting is provided by suitable lamps 31 attached to a slotted light reflector 32 mounted adjacent to the copy drum.

A slotted light shield 33, adapted to protect the xerographic plate from extraneous light, is positioned adjacent to the surface of the xerographic plate. A slot aperture in the light shield extends transversely to the path of movement of the light-receiving surface of the xerog-raphic drum 20 to permit reflected rays from the copy drum to be directed against a limited transverse area of the light-receiving surface as it passes thereunder.

To enable the optical system to be enclosed within a relatively small cabinet, a folded optical system including an object mirror 34, a lens 35, and an image mirror 36, is used in the preferred embodiment of the apparatus.

A document fed through document guides 37 to the copy drum is removably secured thereon by a suitable g-ipper mechanism for movement therewith in timed relation to the movement of the Xerognaphic drum whereby a flowing image of the copy is projected onto the xerographic drum. The copy is held against the surface of the copy drum until gripped by means of document retaining guides 38. Pressure guides 39 and document guard 41 retain and guide the trailing edge of the document on the copy drum. After the copy is scanned it is released from the copy drum to be transported out of the machine by the copy drum and document feed out rollers 42 through document feed out guide 43.

Adjacent to the exposure station is a developing station C in which there is positioned a developer apparatus 50 including a developer housing having a lower or sump portion for accumulating developer material 51. Mounted Within the developer housing is a driven bucket-type conveyor 52 used to carry the developer material previously supplied to the developer housing to the upper portion of the developer housing from where the developer material is cascaded over a hopper chute 53 onto the drum.

As the developer material cascades over the drum, toner particles of the developer material adhere electrostatically to the previously formed electrostatic latent image areas on the drum to form a visible xerographic powder image; the remaining developer material falling off the peripheral surface of the drum into the bottom of the developer housing. Toner particles consumed during the developing operation to form the xerographic powder images are replenished by a toner dispenser 54, of the type disclosed in copending application Serial No. 776,976, filed November 28, 1958, in the name of Robert A. Hunt, now Patent No. 3,013,703, mounted within the developer housing.

Positioned next adjacent to the developing station is the image transfer station D which includes suitable sheet feeding mechanism adapted to feed sheets of paper successively to the xerographic drum in coordination with the presentation of the developed image on the drum at the transfer station. The sheet feeding mechanism includes a sheet source such as paper tray 60 for a plurality of sheets of a suitable support material, that is, sheets of paper or the like, separator rollers 61 adapted to feed the top sheet of the stack of support material through a guide 67 to a sheet conveyor mechanism 62 having paper grippers 63 thereon which carry the sheet support material into contact with the rotating xerographic drum in coordination with the appearance of a developed image at the transfer station.

The transfer of the xerographic powder image from the drum surface to the support material is effected by means of a corona transfer device 64 that is located at or immediately after the point of contact between the support material and the rotating xerographic drum. The corona transfer device 64 is substantially similar to the corona discharge device that is employed at the charging station in that it also includes an array of one or more corona discharge electrodes that are energized from a suitable high potential source and extend transversely across the drum surface and are substantially enclosed with a shielding member. In operation, the electrostatic field created by the corona transfer device is effective to tack the transfer material electrostatically to the drum surface and simultaneously with the tacking action, the electrostatic field is effective to attract the toner particles comprising the xerographic powder image from the drum surface and cause them to adhere electrostatically to the surface of the support material.

As the paper gripper mechanism continues to move forward in its closed circuit, it will strip the support material from the xerographic drum and carry it to a fixing device, such as, for example, heat fuser 7t), whereat the developed and transferred xerographic powder image on the support material is permanently fixed thereto.

After fusing, the finished copy is preferably discharged from the apparatus at a suitable point for collection externally of the apparatus. To accomplish this there is provided a pair of delivery rolls 65 and 66 by means of which the copy is delivered from the machine after it is released by the gripper mechanism. Suitable cam means 68 and 69 are provided at the receiving and delivery stations of the conveyor mechanism, respectively, to actuate the paper grippers at these stations to receive or discharge a sheet of support material.

The next and final station in the device is a drum cleaning station E whereat any powder remaining on the xerographic drum after the transfer step is removed and whereat the xerographic drum is flooded with light to cause dissipation of any residual electrical charge remaining on the xerographic drum.

To aid in the removal of any residual powder remaining on the xerographic drum, there is provided a corona precleaning device 84 that is substantially similar to the corona discharge device that is employed at charging station A. Removal of residual powder from the xerographic drum is effected by means of a web cleaner device 80 adapted to continuously feed a clean fibrous web material into Wiping con-tact with the xerographic drum. As shown, the web material 55 is taken from a supply roll 81 and transported around a cleaning or pressure roll 82, preferably made of rubber, onto a take-up or rewind roll 83.

Any residual electrical charge remaining on the xerographic drum is dissipated by light from a fluorescent lamp 85 mounted in a suitable bracket above the xerographic drum, a suitable starter and ballast being provided for energizing the fluorescent lamp.

Referring now to FIG. 2, there is provided a frame for supporting the components of the apparatus formed by eft-hand plate 10, intermediate plate 11 and right-hand plate 12, connected together and maintained rigidly in spaced relation to each other by suitable tie rods, not shown.

The xerographic drum 20, having a layer of photoconductive insulating material on a conductive drive backing, is mounted on horizontally driven shaft 8H1 that rotates in suitable bearings mounted in plates 11 and 12, respectively. The free end or right-hand end of shaft SI-Il, as seen in FIG. 2, is threaded to receive a nut 24 by means of which the spring 25 encircling the free end of the shaft is biased against the drum to force the drum to the left into driven engagement by the pin 26 extending from the hub portion of driven sprocket 27 secured to shaft 8H1. The left-hand end of the drum is provided with a suitable aperture to receive the pin 26.

Suitable drive means drive the xerographic drum through driven sprocket 27, the copy drum, and the sheet conveyor mechanism at predetermined speeds relative to each other, and effect operation of the paper separator roll, and the web cleaner mechanism, the latter being driven at a speed or speeds whereby relative movement between the Xerographic drum and the web material is effected. Suitable drive means are also provided for effecting operation of the conveyor mechanism and toner dispenser of the developing apparatus assembly.

Plate Cleaning Assembly To remove any residual powder that may remain on the xerographic plate after the transfer process, there is provided a plate cleaning assembly, and to dissipate any residual electric charge remaining on the plate a light source is used to flood the portions of the xerographic plate with light as it passm through the cleaning station.

The plate cleaning assembly used to clean residual powder from the xerographic plate is of the type in which a web of clean, inexpensive, fibrous material is advanced into contact with the plate surface to continuously present a fresh cleaning area of the web to the plate surface for removing residual powder therefrom. Appropriately, this type of plate cleaning apparatus is referred to as a web cleaner.

Referring now to the subject matter of the invention, there is shown in FIGS. 2, 3 and 4, a preferred embodiment of a web cleaner apparatus constructed in accordance with the invention.

As shown, the web cleaner includes a supply roll 81, preferably formed as a disposable cardboard cylinder, carried on supply rol-l shaft SH14 journaled in frame plates 11 and 12. The supply roll is held on the supply roll shaft by means of a spring snap retainer 401 secured to the free end of the shaft, the slotted end of the supply roll engaging the pin 4W2 in the shaft. As web material 403 is pulled from the supply roll, the shaft is rotated imparting a slight resistance to the unwinding of web material fnom the supply roll.

The web material 403, is brought into cleaning contact with the drum surface by cleaning or pressure roll 82, preferably made of rubber, bonded to a support cylinder 404. Cylinder 404 is supported at opposite ends by stub shafts 4&5 and 406 journaled in yokes 4-11 and 412, respectively, fastened in spaced apart relation to each other on torque tube 413. The cleaning or pressure roll is driven by pin 407 on one end of stub shaft 406 engaging the notched end of cylinder 404, a driven gear 408 being fixed to the opposite end of the stub shaft.

The torque tube 413 is rotatably supported on yoke shaft 414 which is fastened at one end by set screw 415 in support 416 secured to frame plate 11. At its outboard end, the torque tube is journaled on tapered pin 419 in support arm 417 pivotally mounted by pin 418 to bracket 421 secured to frame plate 10'. Support arm 417 is normally biased into position to support the outboard end of torque tube 413 by means of coil spring 422 and is locked into support position by means of a suitable fastener 447, such as a 15F Series, Push Button Fastener, marketed by Camloc Fastener Corporation, Paramus, New Jersey.

The torque tube 413', carrying the cleaning or pressure roll 82, is thus adapted to be rotated about the axis of yoke shaft 414 from a first position, as shown in FIG. 1, with the cleaning roll in operative position against the peripheral surface of the xerographic drum with the web material sandwiched therebetween, to a second position, as shown in FIG. 5, in which the cleaning roll is in an inoperative position away from the surface of the xerographic drum.

The cleaning roll is biased into pressure contact with the peripheral surface of the xerographic drum by means of compression spring 423. The compression spring 423 encircles the link 424 extending radially from shaft SHZll, journaled in frame plates 11 and 12.

One end portion of the compression spring engages the shoulder on the lower end of link 424 and the opposite end portion of the compression spring engages the shaft SH21.

Link 424 is movably mounted at one end in a suitable opening in shaft SH21 and its movement in one direction is limited by washer head screw 445 adjustably threaded into the end of the link. With this arrangement the axis of the cleaning roll is biased by the compression spring 423 to a fixed position relative to the peripheral surface of the xerographic drum as determined by washer head screw. The normal force applied by the cleaning roll against the xerographic drum surface with the web material sandwiched therebetween is dependent on the spring rate or deflection of the material of the cleaning roll and the position of the axis of the cleaning roller relative to the xerographic drum as determined by the washer head screw 445 acting as a stop for link 424. Thus, for a predetermined fixed position of the axis of the cleaning roll, the pressure applied by the cleaning roll is dependent upon the durometer hardness rating of the material from which the cleaning roll is made.

It has been found that effective cleaning is obtained when the normal force of the pressure or cleaning roll against the xerographic drum, with the web material therebetween, is in the range of ten to thirty pounds, preferably twenty pounds.

The link 424 and the compression spring act as an overriding linkage permitting the compression spring to either bias the cleaning roll against the peripheral surface of the drum, that is, to bias the axis of the cleaning roll to a fixed position, when in its operative position or to bias the cleaning roll away from the drum to its inoperative position.

To permit an operator to rotate the torque tube to move the cleaning roll to either its operative position or its inoperative position, the torque tube is formed, near its outboard end, with multi-sided flats adapted to receive a suitable wrench. Angular displacement of the torque tube is limited by means of retainer plate 428 secured to switch bracket 429, in position to limit the movement of yoke 412.

The cleaning roll 82 is rotated by the gear 408, on stub shaft 406, engaging the compound gear 431 journaled on yoke shaft 414, axial alignment of this gear being maintained by spacer 434. Compound gear 431 in turn is driven by compound gear 91 on the drum shaft H1 through pinion gear 432 and compound gear 433. Pinion gear 432 and compound gear 433 are mounted on stub shafts 435 journaled in front support plate 436 and rear support plate 437.

Switch bracket 429, front support plate 436 and rear 8 support plate 437 are mounted on studs 438 secured to support 416. The switch bracket is maintained in spaced relation to the front support plate by spacers 441 and the front support plate is held in spaced relation to the rear support plate by spacers 442.

The take-up roll 83, preferably formed as a disposable cardboard cylinder similar to supply roll 81, is positioned on take-up shaft SH13 by a spring snap retainer 401 secured to the free end of the shaft, the slotted end of the take-up roll engaging the pin 402 in this shaft.

Take-up shaft SE13, journaled in frame plates 11 and 12 is driven by compound gear 433 and driving gear 451 journaled on the shaft through a slip clutch arrangement in which the end face :of gear 451 adjacent the torque not 452 serves as one clutch element coacting with the second clutch element or torque nut 452 adjustably positioned on the shaft by torque screw 453 and set screw 454. This assembly is secured against rotation relative to the take-up shaft by engagement of the radial pin 455, carried by this shaft, with the slot provided in the torque screw.

In order to provide means for applying the required pressure to the co'acting clutch elements, gear 451 and torque nut 452, a pair of annular springs 456 encircle the shaft between the gear 451 and thrust

washers

457 and 458 retained by snap ring 461 positioned in a suitable groove formed in the take-up shaft.

The torque nut 452 is adjusted on the torque screw so that the force applied by annular springs 456 is sufficient to permit the gear 451 to drive the take-up shaft through torque nut to rewind the web material onto the take-up roll as it is advanced by the cleaning roll cooperating with the drum surface, while still permitting these clutch elements to slip relative to each other whereby the desired range of tension on the web material is maintained. In this manner the web material is advanced only by the action of the cleaning roll and not by the take-up roll.

With this arrangement the web material is advanced by the cleaning roll at a speed relative to the lineal speed of the drum surface whereby the web material will wipe the residual powder that may remain on the xerographic plate after the transfer process.

The cleaning roll 82 is preferably driven at a rotational speed with respect to the speed of rotation of the xerographic drum to effect a relative web speed in the order of one-thirtieth to one-seventieth of the drum speed. The web speed used is dependent on the relative amount of toner that must be cleaned from the drum surface and the pressure with which the web material is forced against the drum surface. Economically, it is desirable to present the minimum amount of clean web material necessary to effect complete cleaning of the drum surface. In actual practice it has been found, that with a relative web speed of one-fiftieth of the tlinea-l drum surface speed, at a uniform pressure in the order of 1 /2 to 3 pounds per lineal inch across the drum surface as applied by the cleaning roll 82-, sufficient clean web material is presented to the drum surface to effect complete cleaning of the drum surface.

It is apparent that with the web cleaning apparatus of the invention, as described, an operator can readily bias the cleaning roll and associated elements away from the xerographic drum to permit either service of the xerographic :drum or removal of the Xerographic drum from the machine. It is also apparent that with the arrangement of the web cleaning apparatus as shown, an operator can readily remove a contaminated supply of web material and to insert a clean supply of Web material into the machine.

While the invention has been described with reference to the structure disclosed herein, it is not confined to the details set forth, since it is apparent that various modifications can be made to the web cleaner, such as, for example, a pressure pad or other device can be substituted for the cleaning roll. This application is, therefore, intended to cover such modifications or changes as may come within the purposes of the improvements or the scope of the following claims.

What is claimed is:

1. In a xerographic reproducing apparatus wherein a Xerographic drum is journaled in the frame of the apparatus to be rotated through a series of xerographic processing stations, including a plate cleaning station wherein residual powder remaining on the surface of the Xerographic drum is removed;

the improvement including a support secured to said frame;

a torque tube rotatably mounted on said support,

arm means secured to said torque tube for rotation therewith,

roller means rotatably mounted on said arm means,

a supply shaft mounted on said frame,

a take-up shaft journaled in said frame,

said torque tube, said roller means, said supply shaft and said take-up shaft being positioned with their axes substantially parallel to the axis of said Xerographic drum,

a first drive means connected to said roller means for rotating said roller means at a predetermined speed relative to the movement of said Xerographic drum,

a second drive means connected to said take-up shaft whereby a web 'of cleaner material which is advanced from said supply shaft by said roller means is rewound on said take-up shaft,

and means connected to said torque tube whereby said roller means is movable from a first position in which it is in pressure contact with said Xerographic drum with the web of cleaning material sandwiched therebetween,

to a second posit-ion in which said roller means is out of pressure contact with said Xerographic drum.

2. In a xerographic reproducing apparatus wherein a xerographic drum is journaled in the frame of the ma chine to be rotated through a series of xerographic processing stations, including a plate cleaning station wherein residual powder remaining on the surface of the xerographic drum is removed;

the improvement including a torque tube rotatably positioned on said frame,

arm means secured to said torque tube for movement therewith toward and from said Xerographic drum,

roller means rotatably mounted on said arm means,

a supply shaft mounted on said frame,

a take-up shaft journaled in said frame,

a first drive means connected to said roller means for rotating said roller means at a predetermined speed relative to the movement of said Xenographic drum,

a second drive means connected to said take-up shaft whereby a web of cleaner material which is advanced from said supply shaft by said roller means is rewound over said take-up shaft,

and spring biased over-riding linkage means connected to said torque tube whereby said roller means is movable by an operator to a first position in which it is biased into pressure contact with said xerographic drum with the web of cleaning material sandwiched therebetween,

to a second position in which said roller means is biased out of pressure contact with said xerographic drum.

3. In a Xerographic reproducing apparatus wherein a xerographic drum is journaled in the frame of the machine to be rotated through a series of Xerographic processing stations, including a plate cleaning station wherein residual powder remaining on the surface of the xerographic drum is removed;

the improvement including a support secured to said frame;

a torque tube rotatably mounted on said support,

arm means secured to said torque tube for rotation therewith,

roller means rotatably mounted on said arm means,

said roller means including a resilient roll,

a supply shaft mounted on said frame,

a take-up shaft journaled in said frame,

a second drive means connected to said take-up shaft whereby a web of cleaner material which is advanced from said supply shaft by said roller means is wound on said take-up shaft,

and means connected to said torque tube whereby said roller means is movable from a first position in which said resilient roll is in pressure contact with said Xerographic drwm with the web of cleaning material therebetween, to a second position in which said roller means is out of pressure contact with said Xerographic drum.

4. In a xerographic reproducing apparatus wherein a xerographic drum is journaled in the frame of the machine to be rotated through a series of Xerog-raphic processing stations, including a plate cleaning station wherein residual powder remaining on the surface of the Xerographic drum is removed;

the improvement including a support secured to said frame; a torque tube rotatably mounted on said support, arm means secured to said torque tube for rotation therewith,

roller means rotatably mounted on said arm means, said roller means including a roll of resilient material,

a supply shaft mounted on said frame,

a take-up shaft journaled in same frame,

said torque tube, said roller means, said supply shaft and said take-up shaft being positioned with their axe-s substantially parallel to the axis of said xerographic drum,

a first drive means connected to said roller means for rotating said roller means at a predetermined speed relative to the movement of said Xerogr-aphic drum,

and means connected to said torque tube whereby said roller means is movable from a first position in which the axis of said roller means is positioned at a predetermined distance from said xerographic drum whereby said roll is in pressure contact with said Xerographic dr-um with the web of cleaning material therebetween, to a second position in which said roll is out of pressure contact with said Xerographic drum.

5. In a xerographic reproducing apparatus wherein a xerographic drum is journaled in the frame of the machine to to rotated through a series of Xerographic processing stat-ions, including a plate cleaning station wherein residual powder remaining on the surface of the xerographic drum is removed;

the improvement including a support secured to said frame;

a torque tube rotatably mounted on said support,

arm means secured to said torque tube for rotation therewith,

resilient pressure means rotatably mounted on said arm means,

a supply shaft mounted on said frame,

1 1 1 2 a take-up shaft journal-ed in said "frame, Xerographic drum with the web of cleaning material said torque tube, said resilient pressure means, said therebetween, to a second position in which said supply shaft and said take-up shaft being positioned resilient pressure means is out of pressure contact with their axes substantially parallel to the axis of with said xerograplhic drum. said Xerographic drum, 5 a first drive means connected to said tal ie-np slhaft References Cited in the file of this patent whereby a web of cleaner material which 1s advanced from said supply shaft around said resilient pressure UNITED STATES PATENTS means is wound on said take-up shaft, 1,927,784 DWorsky Sept. 19, 1933 and means connected to said torque tube whereby said 10 1,949,868 Keufell Mar. 6, 1934 resilient pressure means is movable from a first posi- 2,832,977 Walkup et al. May 6, 1958 tion in which it is in pressure contact with said 2,878,120 .Mayer et al Mar. 17, 1959

Claims

1. IN A XEROGRAPHIC REPRODUCING APPARATUS WHEREIN A XEROGRAPHIC DRUM IS JOURNALED IN THE FRAME OF THE APPARATUS TO BE ROTATED THROUGH A SERIES OF XEROGRAPHIC PROCESSING STATIONS, INCLUDING A PLATE CLEANING STATION WHEREIN RESIDUAL POWDER REMAINING ON THE SURFACE OF THE XEROGRAPHIC DRUM IS REMOVED; THE IMPROVEMENT INCLUDING A SUPPORT SECURED TO SAID FRAME; A TORQUE TUBE ROTATABLY MOUNTED ON SAID SUPPORT, ARM MEANS SECURED TO SAID TORQUE TUBE FOR ROTATION THEREWITH, ROLLER MEANS ROTATABLY MOUNTED ON SAID ARM MEANS, A SUPPLY SHAFT MOUNTED ON SAID FRAME, A TAKE-UP SHAFT JOURNALED IN SAID FRAME, SAID TORQUE TUBE, SAID ROLLER MEANS, SAID SUPPLY SHAFT AND SAID TAKE-UP SHAFT BEING POSITIONED WITH THEIR AXES SUBSTANTIALLY PARALLEL TO THE AXIS OF SAID XEROGRAPHIC DRUM, A FIRST DRIVE MEANS CONNECTED TO SAID ROLLER MEANS FOR ROTATING SAID ROLLER MEANS AT A PREDETERMINED SPEED RELATIVE TO THE MOVEMENT OF SAID XEROGRAPHIC DRUM, A SECOND DRIVE MEANS CONNECTED TO SAID TAKE-UP SHAFT WHEREBY A WEB OF CLEANER MATERIAL WHICH IS ADVANCED FROM SAID SUPPLY SHAFT BY SAID ROLLER MEANS IS REWOUND ON SAID TAKE-UP SHAFT, AND MEANS CONNECTED TO SAID TORQUE TUBE WHEREBY SAID ROLLER MEANS IS MOVABLE FROM A FIRST POSITION IN WHICH IT IS IN PRESSURE CONTACT WITH SAID XEROGRAPHIC DRUM WITH THE WEB OF CLEANING MATERIAL SANDWICHED THEREBETWEEN, TO A SECOND POSITION IN WHICH SAID ROLLER MEANS IS OUT OF PRESSURE CONTACT WITH SAID XEROGRAPHIC DRUM.