JPH02286557A - Automatic document circulation feeding device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] 11. The present invention feeds originals one by one from a bundle of originals consisting of a plurality of originals to a predetermined original exposure position, and then returns the exposed originals to the originals. The present invention relates to an automatic shield freeze-feeding device for feeding original documents to an exposure position by returning the documents to a stack and repeatedly circulating the documents.

When making multiple copies from a multi-page manuscript using a long-copying machine, it is possible to automatically feed the manuscript onto the contact glass of the copying machine and save time by stacking the pages in the order of pages. 1 from the bottom of the document stack placed on the document placement table
The originals are extracted sheet by sheet and fed onto the contact glass of the copying machine, and the exposed originals are returned and stacked on top of the stack of originals placed on the original f1 tray, and the copies are made. An automatic document circulation feeding device (Recycle) that repeatedly circulates each document in page order through a circulation path consisting of a paper feed path and a return path a number of times corresponding to the number of copies, and feeds the document onto the contact glass.
e automatic document feed
er (hereinafter abbreviated as RADF) is used.

Examples of conventional RADF are shown in FIGS. 14 to 18. The schematic structure and problems will be briefly explained with reference to these drawings.

RADF shown in Figure 14 and RADF shown in Figure 15
It operates on the same principle as . Namely.

The document tray a is equipped with a feed-out bell l-b for feeding the document, and when a stack of documents C is placed on the tray and copying is started, the feed-out belt b extracts the most original document and feeds it. do. This document is received by conveying rollers provided at a predetermined interval in a U-shaped paper feed path, and is set at a predetermined position on the contact glass e by a belt d or roller d'.

After that, when the optical scanning is completed, belt d or roller d
', the paper is sent out to a U-shaped return route, and the receiver is connected to the required number of transport rollers provided on the route, and the paper is delivered to the discharge port f.
The document is discharged onto the document table a, and placed on the document stack C.

In this case, in order to maintain the copy order of the document group, at least a portion of the ejected document must be placed on the topmost sheet of the document stack C, and in order to send the document to the paper feed path again, In this case, at least a portion of the ejected document must be present on the feeding belt b. In other words, paper ejection port f
The following relationship holds between the length Q from the paper feed port a' to the paper feed port a', the length Q2 from the paper discharge port f to the rear end of the feeding belt b, and the length L of the document in the paper feeding direction. It is necessary.

12, /2<L≦Ω1. And, L>Q2 In other words, the RADF shown in FIGS. 14 and 15 has the disadvantage that the minimum length of the document that can be used is considerably limited.

In the RADF shown in FIGS. 16 and 17,
This kind of inconvenience is solved by moving the position of the paper discharge port f' according to the length L of the document in the paper feeding direction. However, in the RADF shown in FIG. 16, the position-variable paper ejection port f' is realized using a telescopically extendable paper ejection guide g, so the variable range is limited by the overlapping length of the paper ejection guide g. Ru. In addition, in the RADF shown in FIG. 17, a foldable paper ejection belt h is used to realize a variable-position paper ejection port f', which is mechanically complex and makes it difficult to assemble and replace the belt h. This has the disadvantage of being time consuming.

With a relatively simple configuration, the position of the discharge port can be changed over a wide range.
A RADF capable of feeding originals of various lengths is disclosed in Japanese Patent Application Laid-Open No. 143125/1983. 1st
FIG. 8 is a diagram showing a schematic configuration of the device, in which a document return path k is provided under the floor covering an area corresponding to the carry-in side of the document table a, and a document return path k is provided on the floor plate of the document table a above. Openings and switching claws i are provided at a plurality of positions in the conveyance direction for discharging the originals conveyed through the return path k upwardly through the floor of the document table a. Further, a discharge section m is provided which is movable in the conveyance direction on the JfX * 2i table and has a paper discharge port f and a conveyance guide Q that guides the document discharged through the return path to the discharge port f using the opening and the switching claw i. It is being

Therefore, if you switch the switching claw i at the position corresponding to the size of the document to be used to the ejection position and move the ejection section m to a position where the document to be ejected from now on can be guided to the ejection port f, The ejected originals are ejected onto a bundle of originals placed on a feeding belt b whose leading edge faces the paper feed port a'. Note that when using the maximum size document that can be used with this device, the ejection section m is located at the rear end of the document table a, and the document that is returned after making a U-turn from the contact glass e is placed in the document return path. The liquid is directly guided to the discharge port f of the discharge portion m by the guide plate j without passing through the discharge portion m. When using a smaller size document, the guide plate j is rotated to a position where the exit faces the document return path k, and the document to be returned after a U-turn is guided to the document return path k.

In the RADF having the configuration shown in FIG. 18, the original is inverted and ejected from the contact glass, and the original is conveyed to the original return path to the ejection section m, which has a paper ejection port f' for ejecting the original onto a stack of originals on the original platen. Since it is formed below the document table, the guide plate constituting the return path can be fixed to the apparatus, which has the advantage of simplifying the structure.

However, on the other hand, the positions of the opening and the switching claw i for sending out documents in the discharge section m are fixed, and due to its structure, the opening positions cannot be provided at narrow intervals. There are some drawbacks. Further, since the return path k is located below the document placement table, there is a problem in that if a document becomes jammed in the return path, it is troublesome to remove it.

In the configuration shown in FIGS. 16 and 17, the document return path after reversal is provided above the document table, and it seems that removing paper jams will be relatively easy, but the position of the ejection port may be moved. Accordingly, it is necessary to extend and contract the guide in the return path, and it is necessary to use a complicated mechanism such as making the guide telescopically extendable or foldable.

In view of the above-mentioned problems of the conventional RADF document return unit, the present invention provides a simple structure that allows the position of the document ejection port and the length of the return path to be easily adjusted according to the document size. An object of the present invention is to provide a RADF equipped with a document return part in which an upper guide constituting a document return path can smoothly change the length and maintain required rigidity.

for The present invention aims to solve the above problems.

The above-mentioned document return unit is movable in the document feeding direction on the top surface of the document tray, receives the originals that are returned along the top surface of the document tray, and ejects the stack of originals placed on the document tray above the top surface. and a discharge section having means for.

an upper guide provided at a distance above a portion of the upper surface of the document mounting table rearward from the ejection section and forming a document return path between the upper surface of the document mounting table, and the upper guides are overlapped. Consisting of a plurality of expandable and retractable guide plates, links extending in the longitudinal direction are fixed on both sides of each guide plate in the expansion and contraction direction, and the links of adjacent guide plates engage with the slits extending in the longitudinal direction at two points. It is characterized in that the sliding direction is regulated by an engaging pin, and the two are slidably connected to each other.

With the above configuration, the ejecting section can move in the document feeding direction on the document placing table and easily change the ejecting position to any position according to the document size. The upper surface of the placing table can be used as the return surface of the document return path. The upper guide of the document return path is made expandable and retractable by stacking a plurality of guide plates on top of each other, and each guide plate is supported by links that are provided on both sides and are connected to each other so that they can be expanded and contracted, and whose directions are regulated. The guide plates expand and contract smoothly, and the connected guide plates can maintain the required rigidity as a whole, and even when the guide is pulled up by the center, both ends will not sag.

EXAMPLES Below, nine examples of the present invention will be described in detail based on the drawings.

FIG. 1 is a side sectional view showing the overall configuration of a RADF as an embodiment of the present invention. This RADF is the copying machine body 1
A paper feed table 1 is provided in a cover-type case that covers a contact glass 101 provided on the top surface of the contact glass 101, and a paper feed table 1 is provided over an area excluding the left and right ends of the upper part of the case, and a paper feed table is provided at the left end in the figure. A paper feeding unit 70 consisting of a paper feeding mechanism that sequentially feeds sheets of paper onto the contact glass 101 from the bottom of a stack of paper stacks placed on the contact glass 101, and a downward running part slidingly contact each other over the entire length of the upper surface of the contact glass 101. A transport unit 71 includes a transport belt 12 that transports the original fed from the paper unit to a predetermined original exposure position on the contact glass and discharges the original from the contact glass after exposing the original, and a transport unit 71 that inverts the original sent from the transport unit. A reversing section 72 that rotates the document, and a return section 73 that returns the document that has been reversed by the reversing section onto the stack of documents on the paper feed table 1.

Hereinafter, each of the paper feeding section, the m-feeding section, the reversing section, and the return section will be explained in order.

Paper Feeding Unit> Side fences 2 are provided on both left and right sides of the front portion of the paper feeding table 1 within the minimum document placement range with respect to the conveying direction. Near the r+iJ end of the paper feed table 1 in the paper feeding direction, two calling rollers 3a and 3b having a cutout are placed in a position where the cutout does not protrude from the document placement surface when the cutout is on the top. It is set in. As shown in FIG. 2, the shafts of the calling rollers 3a and 3b are provided with a slit plate 60 having a slit 61 at the end of the shaft that is detected by a photoelectric sensor 62, and a recess at a position corresponding to the cutout of the calling roller. A pressing roller 64 biased by a spring is provided on the periphery of the positioning plate 63.
is engaged. With these mechanisms, the two calling rollers 3a and 3b rotate synchronously so that the cutout parts are parallel to each other with the same phase, and the slit plate 61 and the photoelectric sensor 6
2 detects and stops the rotation angle at which the sheet feed table 1 and the cutout are on the same plane, and is reliably positioned and held at that position by the positioning plate 63 and the pressing rollers 64.

A presser plate 4 is provided above the calling roller 3a and is driven by a solenoid (not shown) to push down the leading edge of the document at a position shown by a chain line in FIG. 1 and press it against the calling roller 3a. Further above the presser plate 4, as shown in FIGS. 1 and 3(a), a solenoid 67 rotates about the rear end as a fulcrum, and is in a retracted position shown by a broken line in FIG. 1 and an operation shown by a solid line. A stopper 5 is provided which is displaced between the two positions. In the operating position, the toe of the stopper 5 is in contact with the top surface of the table 1 or the top surface of the stack of originals set on the third
(See Figure (b)), it has a function of correcting the skew by abutting the set claw when setting the document bundle and the leading edge of the document that is circulated and returned to the top surface of the document bundle on the table 1 from the rear.

The document bundle pressed against the calling roller 3a by the presser plate 4 is reliably conveyed to the separation section by the synchronous rotation of the calling rollers 3a and 3b.

Reference number 6 in the middle of FIG. 1 is a document setting sensor, which detects that a bundle of documents is set on the table 1, and based on the detection signal, rotates the calling rollers 3a and 3b by a certain amount.
The document bundle is conveyed to the position shown in FIG. 3(b).

The calling rollers 3a and 3b further include an endless belt 7.
It also has a function of reliably feeding the lowest sheet of the stack of documents at the above position in cooperation with a separation section consisting of a separation roller 8 and a separation roller 8. The separation roller 8 rotates in the direction of moving the document in the document conveyance direction at a speed where the circumferential speed becomes the document conveyance speed, while the endless belt 7 is in pressure contact with the circumferential surface of the separation roller 8 over a circumferential length, and rotates in the document conveyance direction. It moves in the opposite direction (direction indicated by arrow A in FIG. 1) at a low speed, for example, about 1/20 of the original transport speed, and the coefficient of friction between the separation roller 8 and the original, the friction coefficient between the endless belt 7 and the original, By appropriately setting the friction coefficient between the originals and the friction coefficient between the originals, the originals sent out from under the original bundle by the calling rollers 3a and 3b are 1
In the case of a sheet, leave the downstream pull-out rollers 9, 10 as is.
If there are two or more sheets, only the lowest one is separated and transported toward the pull-out rollers 9 and 10.

The separation roller 8 has a built-in one-sided clutch, and when the document is conveyed by the pull-out rollers 9 and 10, the separation roller 8
Even when the drive is turned off, the document continues to rotate, reducing the load on document conveyance and conveying the document at a predetermined speed. The separation roller 8 is driven on and off by a clutch (not shown).
When the registration sensor 1 installed at the discharge section from the paper feed section 70 to the conveyance section 71 detects the leading edge of the document, the clutch is turned off and the drive to the separation roller 8 is cut off. It also serves as a detection means for detecting the edge and controlling the original to stop at a predetermined exposure position on the contact glass 101.

The above-mentioned calling rollers 3a, 3b, separation roller 8, and pull-out roller 9 can be driven by a single motor or by separate motors.

<Conveyance Unit> The conveyance unit 71 is made up of one wide conveyance belt 12 wrapped around a pair of rollers 65 and 66, the downward running part of which is pressed against the contact glass 101 by a plurality of pressure rollers 13. The document sent from the paper feed section 70 is conveyed to a predetermined exposure position, and after the completion of the fl light, the document is sent to the reversing section 72.

<Reversing section> The reversing section 72 includes a reversing roller 15 provided along a reversing guide, a pressure roller 16 that presses against the reversing roller 15, and a position indicated by a solid line and a broken line in FIG. 1 on the downstream side thereof. A displaceable switching pawl 14 is provided between them. The switching claw 14 is
In the double-sided original mode, the switching claw 14 is switched to the position shown by the broken line, and the original that has already been exposed on one side is reversed and sent to the conveyance unit 71 again. It is located at the position indicated by the solid line in the figure and is discharged to the return section 73. A reversing sensor 1 is located between the pressure roller 16 and the switching claw 14 and facing the reversing roller.
7 is provided, thereby controlling the drive timing of the conveyor belt 12. The conveyor belt and the reversing roller are each driven by a single motor (not shown).

Return unit> The return unit 73 moves the top of the paper feed table 1 in the document transport direction (
Paper ejection unit 1 movable in the horizontal direction (in Fig. 1)
8 and the rear part of the paper discharging unit in the transport direction, expands and contracts according to the movement of the paper discharging unit 18, and forms a document reversal path between the upper surface of the paper feeding table 1 and the rear part of the paper discharging unit 18. The guide plate 1 includes an intermediate belt 27 for conveying the document discharged from the reversing section 72 to the paper discharge unit 18.

The above guide plate consists of a plurality of guides (three in this example) that can be stacked on top of each other and made to expand and contract.
, 23, and by moving the paper discharge unit 18, the overlapping of each guide plate changes and expands and contracts. The guide plates are arranged so as to overlap one another outwardly in the order of the document conveyance direction, so that the edge of the document conveyed through the return path does not get caught at the overlapping portion of the guide plates.

Exterior covers 24, 25, 26 are placed above each guide plate 21, 22, 23, and the rear end is fixed to a rising part formed by bending the rear end of each guide plate upward, similar to the guide plate. They are provided so that they can be expanded and contracted by being stacked on top of each other. Fourth
6 to 6 are diagrams showing the extended state, intermediate state, and contracted state of the guide plates 21, 22, 23 and the exterior covers 24, 25°26. In these figures, the guide plate 23 and the exterior cover 26 at the rearmost part (the right end in the figures) have their rear ends rounded.
The storage process is shown in a state where the ADF is located at a position that corresponds to the rear end of the ADF.

However, the guide plate and the rearmost part of the exterior cover 23.
26 is not fixed at this position, but is movable between the position shown by the solid line in FIG. 1 and the position shown by the chain line. When the guide plate 21, 22, 23 is extended and its rear end is positioned at the position indicated by the solid line, the distance between the front end surface 40 of the paper ejection unit 18 and the contact surface of the document front end surface of the stopper 5 is the minimum. The distance is set to be slightly longer than the length of the M manuscript. And the rearmost guide plate 2
3 and the exterior cover 26, with their rear ends aligned with the rear end of the RADF as shown by the chain lines in FIG. 1, and the guide plate and exterior cover overlapped to the most contracted state (that is, the state shown in FIG. 6). , the distance between the front end surface 40 of the paper ejection unit 18 at the position shown by the chain line in FIG. 1 and the document front end contact surface of the stopper 5 is slightly longer than the maximum document length. is set to . When the length of the document is between the minimum document length and the maximum document length, the guide plate and the exterior cover are expanded and contracted accordingly, and the front end of the document is brought into contact with the front end surface 4o of the paper ejection unit 18 and the stopper 5. The distance to the surface is i
The distance should be slightly longer than the length of the manuscript.

That is, the front end surface 4o of the paper ejection unit 18 serves as a rear guide when placing a document on the paper feed table 1.

As shown in detail in FIGS. 6 and 7, the paper ejection unit 18 directly receives the original ejected from the outlet 30 of the reversing section 72.
Alternatively, a lower guide 29, which is inclined in a conical manner at the front and which scoops up the original transported by the intermediate belt 27 on the table 1, which is the return surface of the return path, and guides the document to be ejected at the upper part of the front end, and a lower guide 29 that is spaced a certain distance from this , an upper guide formed as the front end of the guide plate 21, a pair of paper ejection rollers 19'' and 19' provided at the entrance and exit of the paper ejection unit transport path formed between these, and these ejection rollers. It has a motor 20 that drives the paper roller. Further, the front part of the exterior cover 24 serves as an exterior cover for the paper discharge unit 18.

The intermediate belt 27 is provided forward of the outlet 30 of the reversing section 72 and is divided into a plurality of strips in the width direction so that the upper surface of the upper running section thereof is flush with the upper surface of the document table 1. When the guide 22 is extended, a driven roller 28 is provided via a leaf spring at a position facing each strip of the intermediate belt, as shown in FIGS. 4 and 7, and the guide 22 is pulled out in the direction of arrow B. When the document is placed above the intermediate belt 27, the driven roller 28 presses against the intermediate belt 27 due to the force of the plate spring and conveys the document, and the guide 22 moves in the direction of arrow C in FIG.
If the intermediate belt is retracted backwards from above, the driven roller 2
8 is flipped up by a member 31 projecting upward from the table surface and retreated from the intermediate belt 27, and is stored behind the reversing section outlet 30 as shown in FIG. In this state,
The largest size document discharged from the reversing unit outlet 30 is conveyed along the paper discharge unit conveyance path by the discharge roller pair 19''19' without being obstructed by the driven rollers or guide plates 22, 23, and is transported from the front end onto the document table. The document is ejected onto a stack of originals placed on the stack, collides with a stopper 5, corrects the skew, and is stacked on top of the stack of originals.

As shown in FIGS. 7 and 12, there are a plurality of paper feed tables 1 extending in the document transport direction between each strip of the intermediate belt 27 and in the range that becomes the return path due to the movement of the paper discharge units 1 to 18. Parallel grooves 55 are provided, and the lower end of the lower guide 29 is provided with a comb-like protrusion 29a that fits into these grooves 55 so as to be able to move smoothly. As a result, the document conveyed by the intermediate belt 27 and the driven roller 28 is reliably and smoothly scooped up by the lower guide 29 and discharged through the discharge section, regardless of the position of the discharge unit 18. The distance from the ejection roller pair 19'' and the pressure roller 16 of the reversing section to the driven roller 28 is set to be shorter than the length of the corresponding document size in the transport direction at any position of the ejection unit 18. This allows documents of any size to be transported smoothly without any problems.

Further, since a belt is used as a means for conveying the original discharged from the reversing section outlet 30 to the paper discharge unit 18, the guide plate is displaced according to the size of the original.

Even if the driven roller 28 is displaced over a considerable range, it can be engaged with the belt. Guide plates 21, 22, 23 that can be expanded and contracted by stacking, exterior cover 24, 25, 26
As shown in FIG. 7, as a means for slidably supporting the paper ejection unit, there is a guide plate, an exterior cover, and a paper ejection unit that extends over the entire sliding range of the guide plate, exterior cover, and paper ejection unit on the back side when viewed from the RADF operator. , a shaft 33 with a circular cross section extends parallel to the document conveyance direction, and is slidably fitted into a circular hole of a support provided on the back side of each guide plate, exterior cover unit, and paper ejection unit 18. are doing.

Links 35, 36, 3 are provided on the back and front sides of each guide plate 21, 22.23 over approximately the entire length of each guide plate.
7 is fixed to the guide plate 21.23, and the link 35.37 fixed to the guide plate 21.23 has a slit 35a extending almost the entire length.
37a are provided, and two engaging pins 3/l are implanted at the ends of adjacent links at a certain distance in the longitudinal direction.
'34''' are connected by engaging with the slits 35a and 37a.

A fixed shaft 39 with a length corresponding to the moving distance of the rearmost guide plate 23 is extended on the frame on the front side of the RADF, and the right end of the guide plate 23 can be swung toward the front in the figure. A recessed portion of a lever 38 having a recessed portion at its tip is slidably engaged by its own weight or by a spring force. R
A guide rail 53 and a rack 50 are fixed to other parts of the front frame of the ADF in the document transport direction, and a plurality of rollers 47 provided on the front side plates of the paper ejection unit 18 are connected to the upper surface of the guide rail 53. A pinion 46 provided coaxially with the roller 47 is engaged with the rack, the pinion 46 is driven by the motor 20, and the paper discharge unit 1
8 to a predetermined position according to the document size and then stopped. Positioning corresponding to the document size can be easily performed by engaging the click pin 45 provided on the front side of the paper ejection unit with the click groove 51 provided on the front frame of the RADF at a position corresponding to the standard paper size. can. Since the click grooves can be provided quite close together, they can be provided to correspond to various original sizes. However, when feeding an intermediate size original, the tip of the click pin 45 should be inserted into the irregularities on the inner surface of the frame. Secure by engaging with the surface. The click pin 45 can be engaged and disengaged from the click groove 51 or the inner surface of the frame using the lever 5 provided on the front end surface of the paper ejection unit.
This can be easily carried out by the operation in step 2, and the paper discharge unit 18 can be easily moved and engaged at a desired position.

The document conveyance path guide and the outer cover of the paper ejection unit 18 are formed as part of the guide plate 21 and the outer cover 24, respectively, but as shown in FIGS. Magnetic pins 49 are fixed to the front and rear sides of the vicinity of the paper roller pair 19', respectively, so as to protrude downward, and correspondingly, magnetic pins 49 are fixed to the main body side of the paper ejection unit 18. , a magnetic attraction means (permanent magnet) 48 having a slightly long groove transverse to the conveyance direction into which the pin 49 can fit is fixed, and by attracting the magnetic pin 49 to the magnetic attraction means 48, a guide is created. The plate 21 and the exterior cover 24 are locked to the paper discharge unit body and can be easily removed to open the conveyance path. The paper ejection unit 18 is slidably supported on the shaft 33 by support portions provided at two locations on the back side thereof.
The two support parts are sandwiched between two forked support parts that slidably support the guide plate 21 on the shaft 33 with almost no gap between them.

Therefore, the paper discharge unit 18, the guide plate 21, and the exterior cover 24 can always maintain their mutual positional relationship, and if the pinion 46 is rotated and the paper discharge unit 18 is moved, the guide plates 21, 22, 23, and Exterior cover 24.2
5.26 expands and contracts as the engagement pin 34'' of the link 36 slides through the slit of the link 35.37.

Near the front end of the exterior cover 25 of the central guide plate 22, there is a position that does not interfere with storage of the exterior covers 24, 25, 26, and approximately near the center when the exterior covers 24, 25, 26 are extended. A handle 32 is attached at the position.

Therefore, regardless of the position of the guide plates 21, 22.23 and the exterior cover 24, 25, 26, by holding the handles 32 and lifting them, the locks 38 at both ends of the guide plates can be used.
39, 48, and 49 are removed, and the guide plate, exterior cover, and link are rotated as a unit around the shaft 33 on the back side, as shown in FIG. 12, and the document return path can be widened. In this case, each guide plate 21, 22, 23
The links 35, 36, 37 on each side are fixed to two pins 34', 34 spaced apart in the transport direction.
Since they are connected by engaging the ``'' with the slits, the three links on each side are held in a straight line when viewed from the side, and each guide plate and exterior cover do not fall apart or both ends droop. , and the locks 38, 39 and 48, 49 can be released without applying much force.

The position where the paper ejection unit 18 is adjusted to the maximum document size (6th
from the state shown in the figure) to the position that matches the minimum original size (the state shown in the figure)
Link 35, 3 when moving to the position @) indicated by the solid line in the diagram
The overlapping state of 6.37 and changes in the positional relationship with respect to the guide shaft 33.39 are sequentially shown in FIGS. 8 to 11. 9 and 10, only the back side is shown for the sake of simplicity. That is, from the state in which the three links 35, 36, and 37 overlap as shown in FIG. 8, the link 35 is pulled out together with the sheet discharge unit 18 and the guide plate 21 as shown in FIG. 9, and then as shown in FIG. As shown, the link 36 is pulled by the rear end of the link 35 and pulled out together with the guide plate 22, and finally, all the links are united and the lever 38 slides along the fixed shaft 39 and moves forward.
It comes to a position corresponding to the minimum document size shown in FIG.

When moving from a position corresponding to the minimum original size to a position corresponding to the maximum original size, this is reversed.

By moving the guide plate and the outer cover in this manner, the guide plate and the outer cover are moved backward from the reversing section exit 30 (to the right in FIG. 1) when the maximum document size is accommodated, and the paper feed You can use the table without wasting it. Note that the method of pulling out the links above is just an example, and you may first pull out links 35 and 36 at the same time,
It is also possible to move all of the links 35, 36, 37 along the axis 39.

By the above-described operation, when the paper ejection unit is moved to a position corresponding to the document size, the guide for the document return path and the exterior cover are automatically formed.

In addition, as shown in FIGS. 1 and 6, the paper ejection unit 18 has a partition plate 411, a partition plate operating mechanism (not shown), a partition plate sensor 43, a paper ejection sensor 42, and a paper ejection unit 18 whose set positions are correct. Positioning sensor 44 that detects whether
is provided.

This positioning sensor 44 detects whether the set position of the paper ejection unit 18 is correct by detecting the rear end of the set document against the stopper 5. If the trailing edge of the document is not detected, either the paper ejection unit 18 is far away from the rear edge of the document, or the paper ejection unit 18 has moved forward too far and the trailing edge of the document is caught on the front wall 40 of the paper ejection unit. Since it is determined that there is a document feeding operation, the document feeding operation is prohibited and the setting position of the paper ejection unit 18 is corrected. The paper discharge unit 18 can be moved easily and smoothly by pressing and releasing the click on a lever 52 (see FIG. 7) provided on the front surface of the paper discharge unit.

Regarding the functions of the partition plate 41 and its related members,
Since it is the same as the conventional RADF, the explanation will be omitted.

Description of Operation> The document feeding operation by the RADF having the above configuration will be explained below using the flowchart shown in FIG.

First, a stack of originals stacked in page order with the image side facing upward is placed on the paper feed table 1 with the leading edge of the stack colliding with the stopper 5, and then the side fences 2 are moved to hold both sides of the stack of originals. . Thereafter, the paper ejection unit 18 is set at a position that matches the document size.

When a paper feed signal is transmitted by turning on the print key of the copying machine, the stopper claw solenoid and the presser plate solenoid are turned on, the stopper 5 is retracted from the leading edge of the paper bundle, and the presser plate 4 calls the document bundle to the roller 3a.

3b, the stack of originals is sent so as to form a wedge shape in which the originals advance from the lowest one by the rotation of the calling roller, and only the lowest original is separated by the endless belt 7 and separation roller 8, and then pulled out by the pull-out roller 9. sent to. When the leading edge of the document is detected by the registration sensor 11, the drive of the separation roller 8 is stopped by the clutch, the document is conveyed to the contact glass 101 only by the pull roller 9, and the document is conveyed to the contact glass 101 by the conveyor belt 12.
1. When the photoelectric sensor 62 shown in FIG. 2 detects the slit 61 of the slit plate 60, the driving of the calling rollers 3a and 3b is cut off, and the driving rollers 3a and 3b stop with their occluded surfaces aligned with the surface of the sheet feeding table 1. Registration sensor 11
After detecting the trailing edge of the document, the conveyor belt 12 reverses at a predetermined timing (based on pulse counting by an encoder), hits the document against the scale 68, and then stops.

As a result, the skew of the original is corrected and the original is stopped at a predetermined exposure position. In this state, original exposure scanning is performed. In response to the exposure scan end signal from the copying machine main body, the conveyor belt 12 rotates forward again, the document is sent to the reversing section 72 and makes a U-turn, and the one-sided or double-sided document that has been exposed on both sides enters the return section 73. Guide plates 21, 22.2 that can be retracted with the intermediate belt 27 and paper feed table 1 according to the document size.
3, is scooped up by the lower guide 29 of the paper ejection unit 18, and is then transferred to the paper ejection roller 1.
9"19', the document is discharged onto the stack of documents on the paper feed table 1.

At a predetermined timing after the paper ejection sensor 42 of the paper ejection unit 18 detects the leading edge of the document, the stopper 5 comes into contact with the top of the document bundle as shown in FIG. 3(b), and the document is ejected from the paper ejection unit 18. When the leading edge of the original documents hits the stopper 5, the skew is corrected and the documents are stacked.

As shown in Fig. 3 (Ca), if a rib 1a of an appropriate height is formed on the upper surface of the paper feed table 1 with a spacing between the pawls provided at intervals on the stopper 5, the paper feed table The document placed on the paper output unit 1 is pushed by the stopper claw and waves so as to enter from the upper end of the rib.
The document discharged from the holder 18 is prevented from slipping under the stopper 5.

While the original on the contact glass 101 is being exposed and scanned, that is, before the exposure is completed, the drive is transmitted to the paper feed unit via the clutch, and the next original is separated and fed. By shortening the replacement interval and transporting at high speed, the total copy processing time can be shortened.

It is common knowledge that if the partition plate 41 is initially placed on top of the stack of originals, the partition plate sensor 43 detects that the partition plate has reached the lowest position, thereby detecting that the original has completed its cycle. be.

- Although the manuscripts that have been reviewed are in good shape to some extent, they are not sufficient and may be in a wavy state. Therefore, before the next paper feeding operation, the calling roller 3a is activated.

It is preferable to rotate the document 3b to apply vertical vibration to the document to arrange it. At this time, the presser plate 4 and the stopper 5 are retracted to a position away from the document, and the calling rollers 3a and 3b generate a conveying force in the conveying direction, so that the front end of the document bundle is separated by the separating roller 8 and the endless belt 7.
It advances to the vicinity of the pressure contact part, and is arranged into a wedge shape with the tip retracted from the lowest position. As a result of the above, the document stack is reset so as not to interfere with paper refeeding, and the next paper feeding operation is started in response to the paper feeding signal.

As described above, according to the present invention, it is possible to change the ejection position of returned originals over a wide range and to any position depending on the original size with a simple configuration, and the upper side of the original return path can be changed. The guide can be smoothly expanded and contracted in accordance with the document ejection position, and the connected guide plates can maintain the required rigidity as a whole.

[Brief explanation of drawings]

FIG. 1 is a side sectional view showing the overall configuration of an automatic document circulation feeding device according to an embodiment of the present invention, FIG. 2 is a perspective view showing a part of the calling roller and its control mechanism, and FIG. 3(a) is a front view showing the document on the paper feed table and the stopper, and FIG.
) are side sectional views showing an enlarged view of the paper feeding section, Figures 4 and 5.
Figure 6 is a side sectional view showing the state of the guide plate and exterior cover when the paper discharge unit of the return section is in various positions, and Figure 7 is a perspective view showing the overall configuration of the return section. Figures 8 to 11 are explanatory diagrams sequentially showing the overlapping state of the links provided on each guide plate when the return section guide plate changes from the most contracted state to the most expanded state, and Figure 12 is FIGS. 13(a) and 13(b) are a cross-sectional view showing a state in which the guide plate is opened, and FIGS. 1 to 18 are side sectional views showing examples of conventional automatic document circulation feeding devices. 1... Paper feed table 3a, 3b... Calling roller 4, presser plate 5... Stopper 8... Separation roller 9... Pull-out roller 12... Conveyance belt 15... Reversing roller 18... Paper discharge unit (discharge section) 19', 19''... Paper discharge rollers 21, 22, 23... Guide plates 24, 25, 26... Exterior cover 27... Intermediate belt 28... Driven roller 29・
...lower guide 29a...comb-like protrusion 32.
・Handle 33・・Shaft 34', 34"・
...Engagement pin 35.36.37...Links 35a, 37a...Slit (locking means) 45...Click pin 47...Roller (locking means) 55...Groove 71...Transportation section 73...Return section 38...Lever 39...Fixed shaft 46...Pinion 48.49...Adsorption member 50...Rack 70...Paper feed section 72...Reversing section No. 1 diagram Figure 15

Claims (1)

[Claims] (1) An original document stack for placing a document stack consisting of multiple originals, and its front edge.The lowest document from the document stack is placed on the document platform with its front edge aligned at a predetermined position. a paper feeding unit having a means for feeding the original one sheet at a time; transporting the original fed from the paper feeding unit to a document exposure position;
a conveying section having a conveying means for discharging the original after exposure of the original; a document return section configured to return the original discharged from the conveying section through a reversing path so as to be superimposed on the stack of originals placed on the document mounting table; In the automatic document circulation feeding device, the document return unit is movable on the top surface of the document placement table in the document feeding direction, and receives the document returned along the top surface of the document placement table and places it on the document placement table. A document return path is provided between a discharge section having a means for discharging the stack of originals above the top surface of the document stack and the top surface of the document tray, which is provided at a distance above a portion of the top surface of the document tray that is rearward of the discharge section. The upper guide is made up of a plurality of guide plates that can be overlapped and expanded/contracted, and links extending in the longitudinal direction are fixed to both sides of each guide plate in the expansion/contraction direction, and links of the adjacent guide plates are fixed to both sides in the expansion/contraction direction. An automatic document circulation feeding device characterized in that the links are slidably connected to each other with their sliding direction regulated by a longitudinally extending slit and an engagement pin that engages with the slit at two locations.