US3476382A

US3476382A - Photoelectrostatic copying machine

Info

Publication number: US3476382A
Application number: US485992A
Authority: US
Inventors: John L Tregay; Edward J Martin Jr
Original assignee: Multigraphics Inc
Current assignee: AB Dick Co
Priority date: 1965-09-09
Filing date: 1965-09-09
Publication date: 1969-11-04
Anticipated expiration: 1986-11-04
Also published as: GB1153330A; DE1522552B1; JPS5021856B1

Description

Nov. 4, 1969 J. L. TREGAY ET AL 3,476,382

PHOTOELEGTROSTATIC COPYING MACHINE Filed Sept. 9. 1965 3 Sheets-Sheet 2 Nov. 4, 1969 J. L. TREGAY ET AL 3,476,382

PHOTOELECTROSTATIC COPYING MACHINE Filed Sept. 9. 1965 3 Sheets-Sheet 5 United States Patent US. Cl. 27152 11 Claims ABSTRACT OF THE DISCLOSURE A copy making machine including an original illuminating station and a copy exposure station makes single or multiple copies of an original. For multiple copies, a gate is positioned to recycle the original around a closed path. In single or multiple operation, a single switch senses the original and causes a copy sheet to be moved .in synchronism to the exposure station. Edge guides engage side edges of the original sheet and include portions extending into the original feed area so that adjustment of the guides is facilitated. A manually operated multiple copy control is locked in position until a final copy is made so that the gate cannot be moved and jamming of an original by the gate is prevented.

The present invention relates to copy machines of the photoelectrostatic type and more particularly to an improved copying machine for making multiple copies of an original.

Automatic photoelectrostatic copying machines produce a copy of a graphic original upon a photoconductive copy sheet that is automatically fed from a supply bin into the machine in response to and in timed relation with the manual feeding of the original. Drive means receive the sheets at their respective feed-in stations and propel the original and copy sheet in synchronization through the machine. The original and copy sheets are moved in synchronization through the machine, the copy sheet being electrostatically charged as it enters and is then exposed at an exposure station by means of a reflected light image produced as the original is moved past an illuminating station.

The latent electrostatic image produced on the copy sheet by exposure is rendered visible by the application of a developer, and is subsequently rendered permanent by fusing. A more complete description of the operation of this type of automatic photoelectrostatic copying machine may be found in a co-pending application of John L. Tregay and Kristian L. Helland, filed Aug. 12, 1964, Ser. No. 389,037, now Patent No. 3,398,259, which is assigned to the same assignee as the present invention.

In many applications of automatic copying machines it is desired to make several consecutive copies of a single graphic original sheet. Automatic copying machines of the type above described are single copy machines, that is, only a single copy is generated each time the original is fed into the machine. In the circumstance where more than one copy is required the original must be refed each time it is returned for each individual copy made. The necessity to manually reinsert the original is inconvenient and slows up the copying process where multiple copies are required. Accordingly it is a primary object of the present invention to provide an improved automatic photoelectrostatic copying machine capable of automatically producing multiple copies of an original sheet.

Machines used in the past for producing multiple copies of an original sheet have suffered from several disadvantages, a principal disadvantage being poor control of 3,476,382 Patented Nov. 4, 1969 the recycling path of the original. Upon being recirculated several times through the machine, the sheet tends to get out of alignment with the initial feed path. This is a problem of some magnitude in multiple copying machines, since a slight error in alignment may be magnified with each successive pass of the original sheet and resulting in loss of synchronization with the copy sheet. Another disadvantage found in machines used in the past is that they required complex control circuit arrangements including sheet sensing means located throughout the machine for controlling the recycling function.

In the manufacture of complicated devices such as photoelectrostatic copying machines, it is desirable to produce a reliable basic machine which can be easily and economically altered to provide specialized functions required by some users. Accordingly, it is an object of the present invention to provide a largely self-contained and compact subassembly which may be used with a standard photoelectrostatic copying machine such as that disclosed in the abovementioned copending application in order to render the machine capable of producing multiple copies.

Machines capable of automatically producing a series of copies of a single original sheet and then returning the sheet to the exterior of the machine customarily include a gate movable between positions for either recycling the original sheet through the machine or for returning the sheet. In machines developed heretofore it has been possible for the operator of the machine inadvertently to manipulate the machine controls and cause the gate to move against an original sheet passing the gate and thus cause the machine to become jammed.

Accordingly, it is an object of the invention to provide a new and improved photoelectrostatic copying machine for producing multiple copies of an original sheet and for automatically returning the original sheet, and to produce a machine overcoming the abovementioned disadvantages of prior machines of this type.

It is a further object of the present invention to provide an improved multiple copy photoelectrostatic copying machine including novel means for preventing an original sheet from becoming jammed in the machine.

Another object of the present invention is to provide an improved multiple copy photoelectrostatic copying machine having a novel locking arrangement for locking the manually operable control while the original sheet is passing the movable gate.

Yet another object of the invention is to provide an improved multiple copy machine having a single sensing means in the path of the original sheet for automatically feeding a copy sheet upon initial insertion of the original sheet and upon each subsequent pass of the recycled original sheet.

Another object of the invention is to provide a novel original sheet handling subassembly for attachment to a standard photoelectrostatic copying machine and to provide such a subassembly which can be conveniently powered by a single rotating shaft in the original machine.

Still another object of the invention is to provide an improved arrangement for maintaining an original sheet in proper alignment throughout successive passes through a photoelectrostatic copying machine.

Another object is to provide novel adjusting means for properly positioning sheet aligning means for original sheets of various widths.

Briefly, in accordance with these and other objects of the invention, a photoelectrostatic copying machine embodying the present invention may comprise an arrangement of driving rollers and guides for moving an original sheet fed into the machine past an illuminating station in order to produce a reflected image used to expose a copy sheet moving simultaneously past an exposure station. The machine includes a feed table and an original sheet feeding station for the manual insertion of an origi nal sheet to be copied into the machine, and also includes a receiving platform to which the original sheet is automatically returned by the machine upon completion of the copying operation. An original sheet inserted into the machine engages a sheet sensing switch contained in a suitable control circuit for automatically feeding a copy sheet past the exposure station in synchronism with the original sheet passing the illuminating station.

In order that multiple copies can automatically be made from a single original, the machine includes guides and drive rollers forming a recycle path for delivering the original sheet from the illuminating station and reintroducing the sheet near the original sheet feeding station. Thus, in accordance with a feature of the invention, the recycling apparatus repeatedly feeds the original sheet past the illuminating station, and on the first and each subsequent pass the sheet engages the single original sheet sensing switch causing a copy sheet to be fed.

In accordance with another feature of the invention, the original sheet returning apparatus and the recycling apparatus are contained in a single unitary subassembly capable of being easily installed on a standard copying machine to render the machine capable of automatically producing multiple copies. When connected to the machine, all the sheet driving rollers of both the sheet return and the recycling apparatus are conveniently powered by a simple drive connection from one rotating shaft of the machine. Thus the subassembly is largely self-contained and can be economically installed to add the recycling feature to a standard copying machine.

In order to maintain the original sheet in properly aligned position during production of multiple copies, when the original sheet is recycled several times, edge guides engage the side edges of the sheet as it moves around the recycle path. Two sets of edge guides are provided and extend along a substantial segment of the recycle path. Adjustment shafts, threaded symmetrically from the center of the recycle path, serve to adjust the position of the guides and to assure that original sheets of any width are properly centered in the machine. Adjustment of the guides is accomplished with a single manual control mounted at the side of the machine.

The edge guides can easily be positioned precisely to fit any original sheet size, since portions of one set of guides extend outwardly along the feed table from the original sheet feeding station and serve as positioning guides during the insertion of the original sheet. Thus the guides may be visually adjusted with the single manual control while the original sheet is lying between the guides on the feed table.

A gate is provided for guiding the original sheet from the illuminating station either to the recycle path or to the return path. Furthermore, the machine includes a manually operated control and a control circuit for programming the machine to make any number of copies, and then to outomatically return the original sheet. Thus the manual control serves to cause the control circuit to move the gate to the recycle position and to set a counting mechanism for any selected number of copies. When the final copy is made, the gate is automatically returned to the return position. In accordance with a feature of the invention, the manual control is locked in position when the gate is in the return position until the original sheet has passed the gate so that the gate cannot inadvertently be moved against the original sheet.

In accordance with another feature of the invention, the operating circuit is prevented from shifting the position of the gate until the original sheet is past. This is accomplished by providing the counting mechanism with a holding feature so that with each pass of an original sheet, the counting mechanism cannot be reactivated until the sheet has cleared the gate.

The invention, together with other objects and advantages, will best be understood from considering the following detailed description in conjunction with the drawings, in which:

FIG. 1 is a fragmentary perspective view of a photoelectrostatic copying machine embodying the present invention;

FIG. 2 is a fragmentary partial sectional view of the machine of FIG. 1 taken along line 2-2 in FIG. 1;

FIG. 3 is a fragmentary partial sectional view illustrating a portion of the structure shown in F-iG. 2 with the movable gate in the return position rather than the recycle position;

FIG. 4 is a partial fragmentary elevational view of a portion of the machine of FIG. 1 with part of the housing removed;

FIG. 5 is a fragmentary sectional view of the machine of FIG. 1 taken substantially along the line 55 of FIG. 1, and illustrating a portion of the path of the copy sheet through the machine; and

FIG. 6 is a diagrammatic and schematic representation of a portion of the control circuit for the machine shown in FIG. 1.

Having reference now to the drawings and initially to FIG. 1, a photoelectrostatic copying machine characterized by the features of the invention is designated generally as 10. The machine 10 serves automatically to pr0- duce upon copy sheets either a single copy or multiple copies of an original sheet fed into the machine. The machine 10 includes a feed table 12 and an original sheet feeding station 13 for the manual insertion of an original sheet into the machine, and also includes a receiving platform 14 upon which the original sheet is automatically deposited upon completion of the copying operation. Movement of the original sheet into the machine causes a copy sheet automatically to be fed from a copy sheet supply enclosure 16 into the machine where a copy is produced thereon. The completed copy is deposited upon a copy sheet receiving platform 18.

The machine 10 includes an original sheet handling subassembly 20, illustrated in detail in FIGS. 2-4, including means defining a recycle path generally designated as 22 and a return path generally designated as 24. Furthermore the original sheet handling subassembly 20 includes a movable gate 26 effective to guide original sheets either to the recycle path 22 or the return path 24.

When an original sheet is fed from the feed table 12 into the original sheet feeding station 13, it is guided by an upper guide 28 and by

lower guides

30 and 32 between a forward pair of original drive rollers 34 and 36. The leading edge of the original sheet as it passes between the rollers 34 and 36 engages a lever 38 which actuates an original sheet sensing switch 40. Suitable apparatus such as the control circuit illustrated in the above referred to Tregay et al. copending application is effective to feed a copy sheet from the copy sheet supply enclosure 16 in response to actuation of the original sheet sensing switch 40. Thus a copy sheet commences to move along a copy sheet path generally designated as 42, a portion of which is illustrated in FIG. 5.

The copy sheet passes between a forward pair of copy

sheet drive rollers

44 and 46 and thereafter the original sheet and the copy sheet pass in synchronism through the machine .10, the original sheet passing across an illuminating station 48 and the copy sheet passing through a charging station 50 and an exposure station 52. As explained in detail in the above-mentioned copending application, a reflected light image passes from the original sheet at the illuminating station through an optics as sembly to the charged copy sheet at the exposure station and an electrostatic charge image is produced on the copy sheet.

The copy sheet is moved from the exposure station 52 by means of a rear pair of copy

sheet drive rollers

54 and 56 and is advanced into the machine for development and fusing before being deposited on the copy sheet receiving platform 18. The original sheet is delivered from the illuminating station 48 by means of a rear pair of

original drive rollers

58 and 60 and is advanced toward the movable gate 26 by means of a curved guide member 62.

If only a single copy is to be made, the movable gate 26 is positioned in the manner illustrated in FIG. 3, and the original sheet is directed along the return path 24. The return path 24 is defined by a fixed guide member 64 and by an elongated guiding portion 26a of the movable gate 26. A pair of

return drive shafts

66 and 68 carrying driving wheels 70 serve to propel the original sheet along the return path 24 and onto the receiving platform 14.

Alternatively, if multiple copies of the original sheet are to be made, the movable gate 26 is positioned as illustrated in FIG. 2 and the original sheet is directed along the recycle path 22 by means of a short curved guiding portion 26b of the movable gate 26. In the recycle path 22, the original sheet is propeled by means of a rear pair of recycle drive shafts 72 and 74 over a lower supporting guide 76. The original sheet is then propelled through a forward pair of

recycle drive shafts

78 and 80, is guided by a center guide 82 and an inner guide 84 along a curved path, and is then reintroduced to the forward original drive rollers by means of the lower guide 32.

In accordance with one feature of the present invention, the original sheet sensing apparatus for causing a copy sheet to be fed into the machine is very simple. It can be seen that the single original sheet sensing switch is actuated not only by the original sheet as it is initially fed, but also on each subsequent recirculation. Thus it is not necessary to provide additional sheet sensing means along the recycle path.

The original sheet handling subassembly 20 comprises a simple and largely self-contained unit fitting conveniently upon the top of the machine 10 and can easily be mounted upon the basic photoelectrostatic copying machine such as the machine disclosed in the copending application referred to above. In order to simplify the connection of the subassembly 20 to the machine 10, and in accordance with a feature of the invention, all of the driving shafts associated with the subassembly 20 are powered from a single one of the rotating shafts of the machine 10 by means of a simple driving arrangement. Thus a driving gear 86 is mounted for rotation between and is engageable with gears on the rear original drive roller 58 and the rear recycle drive shaft 74. Thus rotation of the roller 58 will induce rotation of the shaft 74, which in turn frictionally drives the rear recycle drive shaft 72. In addition, by means of a toothed belt 88, the shaft 74 drives the forward recycle drive shaft 80 and, by means of another toothed belt 90, drives the return drive shaft 68. The

shafts

66 and 78 are driven by friction from the

shafts

68 and 80.

In order to maintain the original sheet in proper alignment during several successive passes past the illuminating station 48 and through the recycle path 22, the machine 10 is provided with a pair of forward edge guides 92 and 94 and a pair of rear edge guides 96 and 98 (see FIGS. 1, 2 and 4). In accordance with the invention, these guides are all adjustable by means of a single crank 100 located at the side of the machine 10 (FIG. 1), and are easily adjusted precisely to fit original sheets of various widths.

The rear edge guides 96 and 98 comprise L-shaped flanges including vertical portions 96a and 98a serving to engage the opposed edges of the copy sheet and hold it in aligned position. These guides also include horizontally arranged

portions

96b and 98b which act as upper guides for the original sheet as it passes over the lower supporting guide 76 along the recycle path 22. The

guides

96 and 98 each carry a sleeve 102 having inwardly protruding pins 102a coupled with oppositely extending helical threads or grooves 103 on a rotatably mounted threaded 6 shaft 104 (FIG. 4). The shaft 104 is threaded symmetrically outwardly from the center so that rotation of the shaft 104 causes the

guides

96 and 98 to move in synchronization inwardly and outwardly along the shaft depending upon the direction of rotation.

Similarly, the

guides

92 and 94 each carry a sleeve 106 having pins 106a engageable with threads or grooves 107 on a rotatably mounted shaft 108 threaded similarly to the shaft 104. The

shafts

104 and 108 are coupled for simultaneous rotation by means of a toothed belt 110 extending between a pair of pulleys 112 and 114 carried by these shafts. The crank 100 is connected to an extension 108a of the shaft 108 so that rotation of the crank 100 by the operator of the machine 10 is effective to simultaneously move the four edge guides 96, 98, 92, and 94. Due to the use of the symmetrically threaded

shafts

104 and 108, the original sheet passing around the recycle path 22 is always properly centered.

Having reference now to the construction of the

guides

92 and 94, these guides include portions 92a and 94a extending along the recycle path 22 for engaging the edges of the original sheet and for guiding it around the inner guide 84. In order to aid in aligning the original sheet as it is initially inserted along the feed table 12 and into the original sheet feeding station 13, the

guides

92 and 94 additionally include portions 92b and 94b extending outwardly across the feed table 12 (FIG. 1). Since the portions 92b and 94b are easily visible to the operator of the machine and since the original sheet before being inserted into the machine 10 lies on the feed table 12 between these guiding portions, the operator may easily adjust the

guides

92 and 94 to fit precisely the width of the original sheet by manipulation of the crank .100. Furthermore since the shaft 104 is arranged to rotate with the shaft 108, the

guides

96 and 98 will be positioned simultaneously with the

guides

92 and 94.

As set forth above, the machine 10 is capable of producing either a single copy or several copies of an original sheet fed into the machine. Whether the original sheet is recycled through the machine or is returned to the receiving platform 14 depends upon the position of the movable gate 26. In order to control the position of the movable gate 26, the machine 10 includes a gate operating solenoid 116 which is controlled by a control circuit generally designated as 118 (FIG. 6). The circuit 118 is set to control the production of different numbers of copies by a manually operated control arrangement generally designated as 120. The control 120 includes a novel locking control for preventing jamming of the machine 10 as the original sheet passes the gate 26.

The solenoid 116 includes an armature 122 connected by means of a pivot pin 124 to a connecting link 126. Another pivot pin 128 joins the connecting link 126 with an operating lever 130. An integral bushing 130a (FIG. 4) on the operating lever 130 is secured to a pivot shaft 132 mounted for rotation on the frame of the machine 10. The gate 26 is secured to the pivot shaft 132 intermediate the length of the gate 26 between the elongated portion 26a and the shorter portion 26b.

When the solenoid 116 is deenergized, the gate 26 is held in a normal return position by a spring 134 connected between the frame of the machine 10 and the operating lever 130. When the solenoid 116 is energized by the control circuit 118, the gate 26 is pivoted in a clockwise direction against the force of the spring 132 from the return position shown in FIG. 3'to the recycle position illustrated in FIG. 2.

The control circuit 118 includes a pair of terminals 136 and 138' for connection to a suitable source of AC power. In order to control the energization of the gate operating solenoid 116, the circuit includes a gate controlling switch 140, which is connected in series with the solenoid 116 across the output terminals of a fullwave rectifier bridge 142 whose input terminals are connected to the power terminals 136 and 138. The switch 140 is normally open and is operated to a closed condition when an operator element 140a is depressed to connect the solenoid 116 across the output of the bridge 142.

In order automatically to program the machine 10 to make either a single copy or to make multiple copies of an original sheet, it is necessary only to use the manually operated control 120. The control 120 includes a rotatable shaft 144 connected to an operating knob 146 conveniently positioned at the front of the machine 10 (FIGS. 1 and 6). The shaft 144 carries a switch operating disc or cam 148 having a recess 150 along the periphery thereof. The knob 146 is set to different angula-rly spaced positions to condition the machine 10 to produce any desired number of copies, such as from 1 to 20 copies. The knob 146 also includes a home or zero position in which the recess 150 receives the actuating or operator element 140a of the switch 140 to open the switch 140. Accordingly, when the knob 1-46 is in its home position, the switch 140 is open, and the solenoid 116 is deenergized to permit the gate 26 to be moved to the return position by the spring 134. Alternatively, whenever the knob 146 is rotated to any position other than the home position, the switch 140 is closed to energize the solenoid 116, and the gate is moved to the recycle ,posiion illustrated in FIG. 2.

In order to meter the number of copies selected by the operator, the machine 10 includes a counting mechanism generally designated as 152 (FIG. 6) including a ratchet wheel 154 secured to the rotatable shaft 144. When the knob 146 is rotated to select a desired number of copies, the ratchet wheel 154 is turned a predetermined number of steps from the home position. The machine 10 is provided with apparatus including a pivotally mounted pawl lever 156 for stepping the ratchet wheel 154 one step toward the home position with each recirculation of an original sheet through the machine.

A counter solenoid 158 includes an armature 159 which is connected to the pawl lever 156 so that when the armature 159 is moved downwardly against the force of a spring 157 by energizing the winding of the solenoid 158, the ratchet wheel advances one step. The solenoid 158 is connected in a circuit generally designated as 161 which energizes the solenoid 158 each time that an original sheet passes through the machine 10.

Whenever an original sheet passes between the forward original drive rollers 34 and 36, the sheet engages the lever 38 and actuates the original sheet sensing switch 40. In response to actuation of the switch 40, a copy sheet is automatically fed along the copy patch 42 and between the forward copy sheet drive rollers 44 and 46 (FIG. During this movement the copy sheet engages a lever 162 which actuates a copy switch 164 (FIGS. 5 and 6). The operation of the copy switch 164, in addition to other functions described in the above-mentioned copending application, closes a circuit in the control circuit 118 to energize a relay 166. The operation of the relay 166 closes a pair of normally open relay contacts 166a to connect a fullwave rectifier bridge 168 to the input potential source. The output terminals of the bridge 168 are connected to the counter solenoid 158. Thus whenever an original sheet passes through the drive rollers 34 and 36, the control circuit 118 of the machine energizes the counter solenoid 158 and advances the ratchet wheel 154 one step toward the home position.

The circuit 118 also includes a hold switch 170 (FIG. 6) connected across the relay contacts 166a which is located downstream of the rear copy sheet drive rollers 54 and 56 (FIG. 5). Since the copy sheet passes through the

rollers

54 and 56 in synchronism with the original sheet passing through the rear

original drive rollers

58 and 60, the copy sheet does not release the hold switch 170 until the original sheet has cleared the gate 26. The switch 170 holds the counter solenoid 158 in its energized condition even though the copy sheet releases the copy switch 164 until the original sheet has cleared the gate 26. Thus the counting mechanism cannot cause the gate 26 to move while the original sheet is passing the gate.

During the production of the last copy, the ratchet wheel 154 is stepped to the home position so that the switch 140 is opened and the gate 26 is moved to the return position. Accordingly, after the last copy is made, the original sheet is guided along the return path 24, through the

return rollers

66 and 68 and onto the receiving platform 14.

If only a single copy is to be made, it is not necessary to use the manual control 120. Rather, the original sheet may be manually inserted into the machine and a single copy is made automatically. To prevent the control from being moved from the home position during such single copy production, the ratchet wheel 154 includes one smooth segment 154a over which the pawl lever 156 merely slips, rather than turning the wheel 154. Thus the counting mechanism 152 is incapable of moving the control 120 away from the home position. This can only be done by manual rotation of the knob 146.

In accordance with another feature of the invention, the manually operated control 120 is provided with a novel locking mechanism generally designated at 172 for preventing the copy sheet from becoming clogged or jammed in the machine 10. If the kno!b 146 were to be inadvertently rotated from the home position while the original sheet is passing the gate 26 in the return position, the original sheet would become lodged between the guide 64 and the gate 26 and jam the machine.

In order to prevent the knob 146 and shaft 144 from being rotated when the gate 26 is in the return position, the locking mechanism 172 includes a pivotally mounted locking lever 174 which normally rests upon the upper edge of the pawl lever 156. The lever 174 includes an extension 174a which rides along the peripheral surface of a hub 178 secured to the shaft 144. In the illustrated embodiment of the invention, the hub 178 comprises an integral portion of the switch operating cam 148 and includes a slot 180.

When the knob 146 is returned to the home position illustrated in FIG. 6, the slot 180 moves under the extension 17401 on the locking lever 174, and the extension drops into the slot 180 when the counter solenoid 158 is actuated to lower the pawl lever 154 and free the lever 174 for downward movement. When the counter solenoid 158 is released, the armature 159 rnoves upwardly and elevates the lever 154 to lift the extension 174a out of the slot 180. However, during the period in which the solenoid 158 is energized, the extension 174a locks the cam 148 and the shaft 144 against rotation, and the knob is firmly held in the home position. Thus the switch cannot be closed and the gate 26 is locked in the return position. Since the solenoid 158 remains energized until the copy sheet, moving in synchronization with the original sheet, clears the hold switch 170, the gate 26 cannot be moved from the return position illustrated in FIG. 3 until such time as the original sheet clears the leading edge of the gate 26.

Reviewing now the operation of the machine 10, the operator first places an original sheet upon the feed table 12 and adjusts the edge guides 92, 94, 96 and 98 to the proper width by rotation of the drank 100. When these guides have been adjusted and assuming that multiple copies are to Ibe made, the operator rotates the knob 146 to select the desired number of copies to be made from the original sheet. Rotation of the knob 146 and the connected cam 148 closes the switch 140, and the gate 26 is moved to the recycle position by the energized solenoid 116.

The original sheet is then inserted through the original sheet receiving station 13 where it actuates the original sheet sensing switch 40 automatically to feed a copy sheet along the copy path 42 in synchronism with the original sheet passing over the illumination station 48.

Assuming that a number of copies of an original are desired, the gate 26 is held in the recycle position by means of the closed gate control switch 140, and the original sheet passes along the recycle path 22 and is recirculated across the illumination station 48. With each pass of the original sheet, the counting mechanism 152 steps the rotatable shaft 144 one gtep toward the home position.

When the original sheet actuates the original sheet sensing switch 40 in order to commence production of the final copy, the counting mechanism 152 moves the ratchet wheel 154 to the home position thus opening the switch 140 and causing the gtae to be moved to the return position. The gate 26 is held in the return position because the locking mechanism 172 locks the shaft 144 against rotation until the copy sheet clears the hold switch 170 and the original sheet clears the leading edge of the gate 26.

What is claimed as new and desired to be secured by Letters Patent of the United States is 1. In a photoelectrostatic copying machine of the type including an illuminating station and an exposure station for producing a copy in acccfzrdance with an original sheet fed through the illuminating station, the combination comprising sheet guide means and sheet driving means forming a closed loop recycle path for producing multiple copies of an original slieet, spaced movable sheet edge engaging means disposed along a substantial portion of said closed loop path for maintaining the original sheet in position throughout successive passes around said closed loop, and adjustment means including a single control external of the machine forfadjusting the distance between said sheet edge engaging means to correspond to the original sheet width.

2. In a photoelectrostatic copying machine of the type having an illuminating station andetfective to produce copies of an original sheet fed past the illuminating station, the combination comprising a feed table external of the machine, sheet driving means and guiding means defining an original sheet path past the illuminating station, an original sheet feeding station adjacent said feed table for the insertion of an original sheet from said table into said original path, means defining a recycle path for recycling an original sheet from the illuminating station to said original path near said original sheetfeeding station for producing multiple copies of an original, spaced edge guides for engaging the spaced edges of an original sheet, said edge guides including first portions extending along said recycle path for maintaining an original sheet in position duringsuccessive passes and including second portions visibly positioned and extending from said original sheet feeding station along said feed table for initially aligning the original sheet, and means for adjusting the spacing of said edge guides to correspond to the sheet width.

3. In a photoelectrostatic copying machine of the type having an illuminating station and effective to produce copies of an original sheet fed past the illuminating station, the combination comprising a feed table external of the machine, sheet driving means and guiding means defining an original sheet path past the illuminating station, an original sheet feeding station adjacent said feed table for the insertion of an original sheet from said table into said original path, means defining a recycle path for recycling an original sheet, from the liluminating station to said original path near said original sheet feeding station for producing multiple, copies of an original, spaced edge guides for engaging the spaced edges of an original sheet, said edge guides including first portions extending along said recycle path for maintaining an original sheet in position during successive passes and including second portions visibly positioned and extending from said original sheet feeding station along said feed table for initially aligning the original sheet, and means including a single manual control for adjusting the spacing of said edge guides to correspond to the sheet width.

4. In a photoelectrostatic copying machine of the type including 'an illuminating station and an exposure station for producing a copy in accordance with an original sheet fed through the illuminating station, the combination comprising sheet guide means and sheet driving means forming a closed loop recycle path for producing multiple copies of an original sheet, adjustable sheet edge engaging means disposed along a substantial portion of said closed loop path for maintaining the original sheet in position throughout successive passes around said closed loop, a housing enclosing the closed loop recycle path and the adjustable sheet edge engaging means, adjusting means connected to the sheet edge engaging means and including operator means disposed outside of the housing for adjusting the sheet edge engaging means to different spaced positions for different size sheets, and means disposed outside of the housing for feeding an original sheet into the closed loop recycle path and including at least one movable guiding means controlled by the adjusting means and operable to positions corresponding to the positions of the sheet edge engaging means.

5. In a photoelectrostatic copying machine for producing copies in accordance with an original sheet, the combination comprising means forming an illuminating path for an original sheet, an illuminating station along said illuminating path, a return path for delivering an original sheet from said illuminating path to the exterior of the machine, a recycle path for recycling an original sheet through said illuminating path to produce multiple copes, guide means movable between a return position for guiding an original sheet from said illuminating path to said return path and a recycle position for guiding an original sheet from said illuminating path to said recycle path, guide controlling means including a manually operable programming control for moving said guide means from said return position to said recycle position and for selecting a number of copies to be made from an original sheet, means for moving said guide means from said recycle position to said return position as the last selected copy is made, and means for locking said manually 0perable programming control as the last selected copy is made until the original sheet has cleared said guide means.

6. Sheet handling apparatus comprising an input sheet path, first and second output paths leading from said input path, gate means movable between a first position for directing a sheet from said input path to said first output path and a second position for directing the sheet from said input path to said second output path, gate controlling means including manually operable means for moving said gate from said first to said second position and for automatically returning said gate to the first position before the last of a predetermined number of sheets had passed said gate, and means for preventing movement of said gate means while a sheet passes said gate.

7. Sheet handling apparatus comprising an input sheet path, first and second output paths leading from said input path, gate means movable between a first position for directing a sheet from said input path to said first output path and a second position for directing the sheet from said input path to said second output path, gate controlling means including manually operable control means for moving said gate from said first to said second position and for automatically returning said gate to the first position before the last of a predetermined number of sheets has passed said gate, and means for holding said gate means in said first position while said last sheet passes said gate, said holding means including means for locking said manually operable control means.

8. Sheet handling apparatus comprising a closed loop path, a branch path leading from said closed loop path, a gate movable between a recycle position completing said closed loop path and a return position effective to 11 guide a sheet into said branch path, gate controlling means including manually operable control means for moving said gate to said recycle position and for selecting a number of times a sheet is to pass around said closed loop path, means responsive to the passage of the sheet around said closed loop path for moving said gate to said return position in order to guide the sheet into said branch path after the final pass, and means for locking said manually operable control means in order to hold said gate in said return position while the sheet passes the gate.

9. Sheet handling apparatus comprising a closed loop path, a branch path leading from said closed loop path, a gate movable between a recycle position completing said closed loop path and a return position effective to guide a sheet into said branch path, gate controlling means including a manually rotatable shaft movable from a home position for controlling the movement of said gate to said recycle position and for selecting a number of times a sheet is to pass around said closed loop path, counting means for moving said shaft toward said home position when actuated, means responsive to the passage of the sheet around said closed loop path for actuating said counting means with each pass whereby said shaft is moved to said home position during the final selected pass, means responsive to movement of said shaft to the home position for returning said gate to said return position in order to guide the sheet into said branch path after the final pass, and means engageable with said shaft for locking said shaft in the home position while the sheet passes the gate.

10. A copying machine for making copies of an original on copy sheets comprising an orginal illuminating station, original conveying means for moving an original through the illuminating station, said conveying means including movable gate means operable to a first position to discharge the original and to a second position to direct the original into a recycle path extending to the illaminating station, control means for selectively moving the gate means between the first and second positions, interlock means in said control means for preventing the movement of the gate means from the first position to the second position, and means for rendering the interlock means effective to prevent movement of the gate means from the first position to the second position during the time interval in which the original is passing through the illuminating station.

11. A copying machine for making copies of an original on copy sheets comprising an original illuminating station, original conveying means for moving an original through the illuminating station, said conveying means including movable gate means operable to a first position to discharge the original and to a second position to direct the original into a recycle path extending to the illuminating station, control means for selectively moving the gate means between the first and second positions, interlock means in said control means for preventing the movement of the gate means from the second position to the first position, and means for rendering the interlock means effective to prevent movement of the gate means from the second position to the first position until after the original has entered the return path and the trailing edge of the original has passed the gate means.

References Cited UNITED STATES PATENTS 1,961,661 6/1934 Fuller 19s 24 X 2,235,844 3/1941 Nelson 271-41 3,091,169 5/19 3 Taini 9s -77.5 3,181,420 5/1965 Rautbord 88-24 EDWARD A. SROKA, Primary Examiner US. 01. X.R.