US3408065A - Sheet handling apparatus for use in a reproduction machine - Google Patents

Description

Oct. 29, 1968 c, GOODMAN ET AL 3,408,065

SHEET HANDLING APPARATUS FOR USE IN A REPRODUCTION MACHINE Filed Nov. 14, 1966 3 Sheets-Sheet l Fig. 8.

INVENTORS Robert C.Goodmon Emilio G. Mostroiunni ATTORNEY Get. 29, 1968 c, GOODMAN ETAL 3,408,065

SHEET HANDLING APPARATUS FOR USE IN A REPRODUCTION MACHINE Filed Nov. 14, 1966 5 Sheets-Sheet 2 INVENTORS Robert C. Goodman Emilio G. Mostroiunni ATTORNEY Oct, 29, 1968 R. c. GOODMAN ETAL 3,408,065

SHEET HANDLING APPARATUS FOR USE IN A REPRODUCTION MACHINE Filed Nov. 14, 1966 3 Sheets-Sheet 3 INVENTORS Robeyt C. Goodman -Emilao G. Mostroiunni ATTORNEY United States Patent 3,408,065 SHEET HANDLING APPARATUS FOR USE IN A REPRODUCTION MACHINE Robert C. Goodman, Binghamton, and Emilio G.

Mastroianni, Endicott, N .Y., assignors to GAF Corporatiou, a corporation of Delaware Filed Nov. 14, 1966, Ser. No. 594,202 9 Claims. (Cl. 271-64) ABSTRACT OF THE DISCLOSURE The present invention relates to sheet handling apparatus for use in reproduction machine of the type adapted to reproduce indicia carried by an original sheet on a copy sheet, while the sheets are passed through the machine in a superimposed relationship. Specifically, the handling apparatus includes improved vacuum operated means to effect separation of the superimposed sheets after such sheets have been passed through an exposure station of the machine and means adapted to insure proper transfer of the superimposed sheets from the exposure station to the sheet separating means.

The present invention has particular utility for use in reproduction machines of the type through which an original sheet and copy sheet are passed in a continuous feeding operation; the sheets being initially fed in superimposed relationship through an exposure station after which the sheets are separated to permit the copy sheet to be passed through a development station and the original sheet to be immediately discharged from the machine.

Heretofore, it has been proposed to employ in reproduction machines of the general type under consideration sheet separators which operate on a vacuum principle. In their simpliest form, sheet separators of the prior art comprise a pair of rotatably supported drums having peripheral apertured surfaces adapted to define a nip through which superimposed original and copy sheets are adapted to be passed. A pump is employed to create a reduced pressure within the drums, whereby upon passage of the sheets through the nip, the respective sheets are drawn into engagement with the apertured surface of each drum and the sheets separated. Such devices are conventionally provided with stationary means adapted to shield or cover the apertured surface of the drum except through an arc of the drum surface adjacent the nip. It has also been proposed to provide sheet separators in the form of stationary vacuum chambers having facing ap-ertured surfaces between which superimposed sheets are adapted to be conveyed by suitable means, such as conveyor belts. Vacuum separators of the type described have been found to be not only inefficient in operation but to create a noise level which is found objectionable in many machine installations.

Further, in prior reproduction machines various means have been employed to effect separation of the original and copy sheets from an exposure station and effect orderly transfer of such sheets to a sheet separator. However, in machines of this nature, the means employed are complex in structure and operation, and thus are not only expensive but diificult to repair in the event of wear or breakage thereof.

Accordingly, it is an object of the present invention to overcome the disadvantages of prior sheet handling ap paratus used in reproduction machines.

It is a more specific object of the present invention to provide vacuum operated means to separate original and copy sheets, which means are characterized by an improved operating efficiency and a low operating noise level.

3,408,065 Patented Oct. 29, 1968 "ice A still further object of the present invention is to provide in a reproduction machine improved sheet handling apparatus including improved means adapted to insure proper transfer of original and copy sheets from an exposure station to a sheet separator.

Other objects and many of the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings in which:

FIG. 1 is a perspective view of the reproduction machine of the present invention showing portions of machine cabinet broken away;

FIG. 2 is a sectional view taken generally line 22 in FIG. 1;

FIG. 3 is a sectional view line 3-3 in FIG. 2;

FIG. 4 is a sectional view line 4--4 in FIG. 3;

FIG. 5 is a sectional view line 5-5 in FIG. 2;

FIG. 6 is a sectional view line 6-6 in FIG. 5;

FIG. 7 is a sectional view line 77 in FIG. 2; and

FIG. 8 is a sectional view line 88 in FIG. 7.

Referring now to the drawings wherein like reference numerals designate like or corresponding elements throughout the several views and wherein a preferred embodiment is illustrated, there is shown in FIG. 1 a reproduction machine generally designated as reference numeral 1 in which the present invention is adapted for use.

As shown an original sheet 2 and a copy sheet 3 are adapted to be assembled in superimposed relationship and fed by an operator into the machine through an inlet opening 4. Thereafter, the sheets are automatically fed continuously through an exposure station, generally indicated by reference numeral as 5, and then through a separator, generally indicated by reference numeral 6. After separation of the sheets, the original sheet is discharged from the machine through an outlet opening 7 and the copy sheet is passed to a development station, not shown, and thereafter discharged from the machine through an outlet opening 8. The exposure station 5, which forms no part of the present invention, normally includes a rotatably supported glass drum 9 having a mercury light source, not shown, disposed therein. It will be apparent that when the sheets are presented to the surface of drum 9, as indicated in FIG. 2, the chemically treated or sensitized surface of the copy sheet is exposed to ultra violet rays passing from the light source through the original sheet in a manner well understood in the art.

At this point, it will be understood that the sheet handling apparatus of the present invention includes an improved sheet separator 6 and improved means, generally indicated as reference numeral 10, adapted to transfer the superimposed sheets from exposure station 5 to the separator.

The sheet transfer means 10 is shown in FIG. 2 as including a separator assembly 11 and a conveyor 12. In the preferred embodiment of the present invention, conveyor 12 is in the form of a plurality of spaced apart endless belts 13, which are adapted to be driven in the direction indicated by arrow 14 by one or more drive rollers 15, and which pass from machine inlet 4, about the exposure drum 9, through separator 6, and thereafter return to inlet 4 through the development station, not shown. However, it will be understood that conveyor 12 may be of any other desired construction and may be limited in along the taken generally along the taken generally along the taken generally along the taken generally along the taken generally along the taken generally along the employment to assisting transfer of the superimposed sheets from drum 9 to separator 6.

The separator assembly 11 is shown particularly in FIGS. 2 and 7 as comprising a supporting shaft 16 having a plurality of spaced circumferentially extending grooves 17; a plurality of resilient plastic separator plates 18 which are adapted to be rotatably supported on shaft 16 within grooves 17; and springs 19 which normally tend to pivot plates 18 about the axis of shaft 16 in the direction indicated by arrow 20.

Shaft 16 is adapted to be supported in a spaced parallel relationship with respect to the axis of drum 9 by flanges 21, only one being shown in FIG. 2 which may be aflixed as by welding to extrusion 22. Extrusion 22 may be mounted on machine side plates 23, 24 in any suitable manner, not shown.

Referring again to FIGS. 2 and 7, it will be seen that plates 18 are of relatively thin construction and have a sharp edge portion 25 defined by concave end edge portion 26 and side edge portion 27 of the plate. It will be apparent that with plates 18 mounted on shaft 16 in the manner more clearly hereinafter described, sharp edge 25 is disposed parallel to the axis of drum 9 and in slidable engagement with the peripheral surface thereof.

Plate side edge portion 27 is shown in FIGS. 2 and 8 as being provided with a curved recessed opening 28, which is described by a circle whose radius is slightly greater than the radium of the grooved portion of shaft 16 and whose center is disposed slightly inwardly from side edge 27. It will be apparent that by positioning the center of opening 28 in the manner described there is formed along the side edge portion 27 a pair of inwardly directed portions 29 and 30, which due to the resilient nature of the plates, are adapted to snap over and thereafter serve to retain shaft 16 within opening 28. Further, it will be apparent that when plates 18 are positioned within grooves 17, the side edges 31 of the grooves tend to prevent tilting of plates 18 with respect to the axis of shaft 16, whereby the plates are constrained to pivotably motion in parallel planes about shaft 16 and sharp edge 25 is maintained in line contact with the peripheral surface of drum 9.

Referring again to FIGS. 2 and 7, it will be seen that springs 19 are provided one for each pair of adjacent plates 18. Spring 19 is of a generally U-shaped design 'having a base portion 32 and leg portions 33 which are coiled about shaft 16 as at 34. The free ends of spring leg portion 33 are shown in FIG. 7 as being deformed as at 35 and as being removably received within slot cut-outs 36 provided in side edge portion 37 of plate 18. By viewing FIG. 2 it will be understood that when deformed end 35 is snapped into plate cut-out 36, the spring is tensioned whereby forcing spring base portion 32 into engagement with extrusion 22 and sharp edge 25 into engagement with the surface of drum 9.

By constructing plates 18 of inexpensive plastic manufacture in the manner described, several desirable results are obtained. First, a desired amount of pressure may be employed to maintain the sharp edges 25 of plates 18 in engagement with drum 9 without undesired abrasion of the surface thereof. Also, when the sharp edge of any one plate becomes dull or broken, the plate may be quickly and easily removed and a new plate snapped onto shaft 16 without disturbing the remaining plates of the assembly. Further, due to their low initial unit cost it has been found practical to merely discard worn plates rather than attempt to regrind the plates to reproduce the sharp edge portion thereof.

Separator 6 is shown in FIG. 2 as including first and second vacuum chambers or tanks 37 and 38 having facing apertured walls 39 and 40, respectively. Chambers 37 and 38 are connected to a third chamber 41 by conduits 42 and 43, respectively (FIG. 1). Preferably, chamber 41 is disposed within the supporting base of machine 1 and formed at least in part by the side 44 and end 45 walls of the machine. Air may be removed from chamber 41 and thus from chambers 37 and 38 by suitable means, such as a compressor 46. It will be understood that at least conduit 42 is provided with an air fiow control valve 47, by which an operator of the machine may selectively control the rat-i0 of pressures existing within chambers 37, 38 for the reason hereinafter discussed.

In FIG. 2 apertured walls 39 and 40 are shown as being spaced apart and as cooperating to define a vertically extending passageway having an inlet end 48 and outlet end 49. It will be apparent that the portions of the apertured walls 39 and 40 which define a lower portion 50 of the passageway extending from inlet 48 to an intermediate point, indicated by dotted line 51 in FIG. 2, are substantially parallel. Thereafter, the spacing between apertured walls 39 and 40 progressively inceases toward outlet 49 to define an upper passageway portion 52.

Received within the passageway for movement in sliding surface engagement with apertured walls 39 and 40 are respective endless belts 13 and 53. As indicated in FIGS. 3 through 6, belts 13 and 53 are equally spaced across the apertured walls and overlie one another dur-- ing upward movement through the passageway. Belts 53 are shown as being of perforated or open weave construction so as to freely permit the passage of air therethrough, and as being driven in the direction indicated by arrow 54, as by a drive roller 55.

Now referring to FIGS. 2 through 6, it will be seen that apertured walls 39 and 40 are provided with spaced relatively offset slot openings 56 and 57, respectively, which extend vertically between points adjacent the inlet and outlet ends 48 and 49 of the passageway. In FIGS. 5 and 6 slot openings 56 are shown as being of uniform width along the length thereof and as being disposed in the vertically extending space defined by adjacent belts 13, and slot openings 57 are shown in FIGS. 3 and 4 as being contoured and as being disposed in an underlying relationship to belts 53. It will be apparent that when the pressure within chambers 37 and 38 is reduced and the superimposed original and copy sheets are passed upwardly through the passageway between belts 13 and 53 in the manner to be described, air is drawn inwardly through slots 57 and belts 53 thereby tending to draw original 2 into engagement with belts 53, and air is drawn inwardly through slots 56 thereby tending to draw copy sheet 3 into engagement with adjacently disposed pairs of belts 13.

In FIG. 3 contoured slot openings 57 are shown as having relatively wide mid portions 58 which extend above. and below the intermediate point 51 of the passageway. It will be seen that mid portion 58 gradually tapers into relatively narrow upper slot portion 59 and abruptly changes as at 60 into a relatively narrow lower slot portion 61.

Chambers 37 and 38 are provided with corrugated baffles 62 and 63 which are affixed in any suitable manner, not shown, to the inwardly facing surfaces 64 and 65 of apertured walls 39 and 40, respectively. Baffles 62 and 63 cooperate with surfaces 64 and 65 to define a plurality of vertically extending channels 66 and 67 provided one for each of slot openings 56 and 57, respectively. Channels 66 and 67 are shown in FIG. 2 as being closed at their upper ends 68 and as being in fluid communication with the interior of chambers 37 and 38 at their lower ends 69. Further, as will be apparent from viewing FIG. 2, the cross-sectional area of each of the channels is substantially constant from closed upper end 68 to passageway intermediate point 51, and is progressively increased from intermediate point 51, to open lower end 69. By arranging channels 66 and 67 in the manner described, it will be apparent that air drawn inwardly through slot openings 56 and 57 is forced to travel downwardly through the channels adjacent wall surfaces 64 and 65, thereby tending to create reduced static pressure adjacent such surfaces. It has been found that the reduced static pressure thus produced augments the reduced pressure created within chambers 37 and 38 by compressor 46, thereby permitting a compressor of relatively smaller displacement to be employed in the machine. Further, it has been found that a smaller mass flow of air is required to effect separation of the sheets, thereby permitting the operating noise level of the separator to be considerably reduced over that of separators presently available.

Suitable means, such as L-shaped reciprocably mounted extrusions shown in phantom line as 70 in FIG. 2, may be employed at one or both sides of each of chambers 37 and 38 to selectively close off one or more of channels 66 and 67 and the lower ends of slot openings 56 and 57. This is a particularly desirable feature of the present invention, since it permits an operator of the machine to selectively seal 01? portions of the apertured walls of 39 and 40; when an original sheet having a width less than that of the walls it is desired to be reproduced. Sealing of the aperture walls in this matter reduces the noise level of the machine and permits compressor 46 to run at a lower operating speed.

The operation of the sheet handling apparatus of the present invention may be best described with reference to the overall operation of machine 1. Prior to initiating a reproduction operation an operator first energizes a suitable electrical control circuit, not shown, whereupon compressor 46 is operated to withdraw air from chambers 37, 38 and 41; rollers and 55 are powered to drive belts 13 and 53 in the directions indicated by arrows 14 and 54, respectively; and the light source within drum 9 is energized. Thereafter, the operator may seal off portions of the apertured walls 39 and 40 by moving L- shaped extrusions 70 in accordance with the width of the original sheets to be reproduced. The operator may also at this time adjust flow valve 47 to adjust the ratio of pressures present within chambers 37 and 38. In most instances it has been found that a higher degree of vacuum must be maintained in chamber 38 than in chamber 37 since the original sheet has generally been used on several occasions and thus has been creased and bent. Additionally, the increased vacuum in chamber 38 is necessary inasmuch as the path of the original sheet is changed when leaving the outlet 49 of the passageway, whereas the path of the copy sheet is straight. It has also been found that when the original sheet is formed from a plastic material such as Mylar a higher degree of vacuum must be maintained within the chamber 38 to achieve effective separation of the sheets, than would be necessary if the orginal sheet is formed of vellum.

The machine is now ready for the reproduction operation. The operator then assembles the original sheet and the copy sheet in a superimposed relationship and feeds the sheets into the machine through opening 4 and onto the conveyor belts 13. The superimposed sheets are thereafter presented to the surface of drum 9 by belts 13 and the sensitized surface of the copy sheet 3 is exposed to the ultra violet rays passing from the exposure station light source outwardly through the wall of drum 9 and through the original sheet 2. It has been found in practice that the conditions to which the superimposed sheets are exposed in passing over drum 9 tends to temporarily adhere the original sheet to the sensitized surface of the copy sheet and tends to produce a curl in the sheets corresponding to the curved surface of the drum. Thus, upon continued movement of belts 13 the leading edge portion of the superimposed sheets, separates from the belts adjacent the upper portion of drum 9 as viewed in FIG. 2 and is thereafter peeled from the surface of drum 9 by the sharp edge portions of plates 18. After separation from tthe drum 9, the leading edge portion of the superimposed sheets is guided upwardly by concave and edge surfaces 26 of plates 18 towards passageway inlet 48 and between belts 13 and 53. Upon passing the upper end of edge guide 26, as viewed in FIG. 2, an upwardly moving air current produced by air being drawn into the lower end portions of slot openings 56 and 57 draws the leading edge portion of the superimposed sheets upwardly between belts 13 and 53 whereby the immediately following portions of the superimposed sheets are drawn into engagement with belts 13.

As the leading end portion of the superimposed sheets moves upwardly through the passageway, air is continuously drawn through slot openings 56 and 57 over the leading edges of sheets 2 and 3 at relatively offset points spaced transversely of the apertured walls of the chambers, thereby tending to peel apart the leading edges of the sheets. Due to the progressively decreased cross-sectional size of channels 66 and 67 in the direction of sheet movement, the velocity of the air flowing downwardly through the channels is progressively increased, thereby producing a corresponding increase in the degree of suction exerted on both the original and copy sheets. Normally, the leading edges of the sheets are separated immediately after passing the abrupt change in contour, as indicated at 60, of slot openings 57, due to the maximum suction effect produced in the area defined by the relatively wide mid portion 58 of such openings. After separation of the sheets, the copy and original sheets are drawn into the surface engagement with belts 13 and 53, respectively, and thereafter are positively conveyed by the belts upwardly through passageway outlet 49. Belts 13 may be employed to convey the separated copy sheet through a development station, not shown. The original sheet may be separated from belts 53 during passage over drive roller 55 by any suitable means, not shown, and thereafter passed through machine outlet 7.

It should be understood that the foregoing relates to only a preferred embodiment of the invention and that it is intended to cover all changes and modifications of the example of the invention herein chosen for the purposes of the disclosure, which do not constitute departures from the spirit and scope of the invention.

The invention claimed is:

1. An improved paper separating apparatus for use in a reproduction machine having an exposure station including a rotatable drum over which an original sheet and a copy sheet are passed in superimposed relationship, said handling apparatus including means to separate said superimposed sheets passed from said drum, said separating means comprising:

first and second chambers, said chambers being spaced apart and having facing apertured walls adapted to define a passageway between said chambers having an inlet and outlet;

pressure reducing means adapted to apply reduced pressure within said chamber;

conveyor means associated with each of said chambers and adapted to be moved within said passageway from said inlet towards said outlet, the improvement comprising a baffle means disposed in at least said second chamber adjacent the inward surface of said apertured wall, said baffie means defining with said inward surface at least one channel adapted to conduct air into said chamber through said apertured wall such that the air flowing in said channel is in a direction opposite to the path of movement of said conveyor means through said passageway.

2. Apparatus in accordance with claim 1, wherein the spacing between said apertured Walls from a point adjacent said inlet to an intermediate point of said passageway is substantially constant and from said intermediate point to a point adjacent said outlet of said passageway is progressively increased, and the cross-sectional area of said channel is progressively increased from adjacent said intermediate point in said direction of air flow.

3. Apparatus in accordance with claim 1, wherein the apertures of said wall of said second chamber are in the form of spaced slots extending between points adjacent said inlet and outlet of said passageway and a channel is provided one for each of said slots.

4. Apparatus in accordance with claim 3, wherein each of said slots has a relatively narrow portion adjacent said inlet and a relatively wide portion adjacent an intermediate point of said passageway, and said slots abruptly increase in width adjacent said intermediate point.

5. Apparatus in accordance with claim 3, wherein means are provided to selectively prevent flow of air through at least one of said channels.

6. Apparatus according to claim 1, wherein said pressure reducing means comprises:

a third chamber, said third chamber forming in part the base of said reproduction machine;

conduit means adapted to connect said first and second chambers to said third chamber; and

compressor means adapted to withdraw air from said third chamber.

7. Apparatus in accordance with claim 6, wherein said conduit means have valve means adapted to selectively control the ratio of pressures within said first and second chambers.

8. Apparatus in accordance with claim 1, wherein the handling apparatus additionally includes means to transfer said superimposed sheets from said drum to said separating means, said transfer means including a separator assembly which comprises in combination:

a supporting shaft aligned with the axis of said drum;

a. plurality of plate members individually mounted on said shaft for pivotable movement in spaced parallel planes disposed normal to said drum axis, each of said plates having a sharp edge portion aligned with said drum axis and defined by meeting side and end edge portions of said plate, said end edge portion forming a convex guide surface for said superimposed sheets; and

spring means, said spring means being adapted to normally bias said sharp edge portion into engagement with the peripheral surface of said drum.

9. Apparatus in accordance with claim 8, wherein said plates are formed from a resilient plastic material, said shaft is provided with a plurality of spaced apart circumferentially extending grooves each of which is adapted to receive one of said plates, the radially extending walls of said grooves being adapted to maintain said plates in spaced apart relationship, and said side edge portion is provided with a curved recessed opening adapted to rotatably receive said shaft and inwardly directed portions adjacent said recessed opening, the spacing between said inwardly directed portions being less than the diameter of the grooved portions of said shaft, whereby when said plates are mounted within said grooves of said shaft, said inwardly directed portions are adapted to resiliently maintain said shaft within said recessed opening.

8/1961 Germany. 4/1962 France.

EDWARD A. SROKA, Primary Examiner.

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