JPS59212857A - Circulation type sheet supplying device - Google Patents

Abstract

PURPOSE:To take numbers of copies of a sheet original in various modes by attaching a device which turns over the sheet original. CONSTITUTION:The main device A1 of an automatic sheet original supplying device A carries the lowest sheet original on an original tray 1 by a conveyor belt 3, and the sheet is sent onto platen glass 12 through a paper feed roller 2. The sheet original after the copying operation of a copying machine body B is dischrged from on the platen glass 12 by a belt 8, and carried to the highest position of sheet originals through another path by a couple of rollers 11 and 11a through the operation of a conveyance path selection pawl. When a subordinate device A2 is attached, the sheet original on the platen glass 12 is carried to under the roller couple 9 of the subordinate device 2 and then returned to the highest position of the sheet originals, so the sheet original is turned over to take a both-surface copy.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a circulating sheet feeding device that feeds a sheet set on a sheet stacking section to a predetermined processing section and returns the sheet to the sheet stacking section again.

A typical example of this type of apparatus is a circulating automatic document feeder installed in an image forming apparatus such as a copying machine.

This separates the originals stacked and set on the original table as a sheet resting unit, one by one, and transports them onto the platen glass of the original illumination unit of an image forming apparatus such as a copying machine, which is a predetermined sheet processing part. After the exposure is completed, the original is transported again to the original platen during the day, and the cycle of feeding one method of original from the original platen to the platen glass is performed sequentially for each original set on the original platen. One copy of all the stacked documents can be obtained by circulating the stacked documents once, and the required number of copies can be obtained by repeatedly feeding the stacked documents a predetermined number of times. Therefore, it is extremely effective in automatically and quickly copying a large number of sheet originals.

There are variations as shown in 1) to 5) below in the manner in which sheets are fed from the sheet stacking section to a predetermined location and vice versa. For convenience, one side of the sheet is the first side, and the other side is the second side.
The sheet is set on the sheet tray 16 with the first side facing upward.

1) Stop-transfer-feeding The first side upward facing sheet of the sheet loading section) is fed to a predetermined location with the first side facing upward.

2) Reverse feeding Contrary to the above, the paper is fed with the first side facing downward.

3) Reversing and re-feeding: The sheet that has once been forward-feeded or reverse-fed to a predetermined location is then introduced into the reversing section, the first side is turned over downward or upward, and the sheet is again fed to the predetermined location.

4) Normal discharge The sheet with the first side facing upward or downward at a predetermined location is discharged with the first side facing upward or downward with respect to the sheet stacking section.

, i) Reverse discharge Contrary to the above-mentioned forward discharge, a sheet with the first side facing upward or downward on a predetermined portion is reversed and discharged with the first side facing downward or upward with respect to the sheet stacking section. do.

For example, a circulating document automatic feeder of an image forming apparatus may be equipped with all the feeding and ejecting functions described in items 1) to 5) above, and these feeding and ejecting functions may be combined to create a document mounting table. By feeding and ejecting the original between the copying machine and the platen glass in various ways, it is possible to automatically execute image forming processes in various copying modes A to D below. In this example, it is assumed that the downward surface of the document fed onto the platen glass is subjected to illumination itW light processing. Also, a single-sided original is one in which the first side of the sheet is an image side and the second side has no image, and a double-sided original is one in which both the first and second sides of the sheet are image sides. is an image forming process in which an image is formed on the first side of a copying material sheet and no image is formed on the second side, and double-sided copying is an image forming process in which an image is formed on the first and second sides of a copying material sheet, respectively. means.

A. Single-sided original - Single-sided copy mode Place the original with the first side (the image side) of the single-sided original facing upward.
When the document is set on a table, the document is fed by reverse feeding. As a result, the first side, which is the image side of the single-sided original, is fed downward onto the platen glass, and single-sided copying is performed on that image side on the image forming apparatus side (hereinafter simply referred to as the main side). . The document is discharged in reverse. As a result, the original is returned to the original placing table with the first side facing upward in the same way as when it was initially set.

When a single-sided original is set with its first image side facing down on the original table, contrary to the above, the original is fed in a forward direction, and the document is ejected in a forward direction.

B. Single-sided original - double-sided copy mode The feeding and ejection of the original is the same as in section A above. Then, the second side of the copying material sheet is subjected to the copying process of the image of the supplied single-sided original, thereby obtaining a double-sided copy.

C1 Double-sided original--single-sided copying mode When a double-sided original is set on the original table with the first side facing up, the original is fed by reverse feeding. As a result, the first side of the double-sided original is fed downward onto the platen glass, and the copying process for that image side is performed on the first side of the copying material sheet on the machine side, and the first side of the double-sided original is A single-sided copy is obtained.

Next, the document on the platen glass with the first side facing downward is reversed and fed again. By kneading, the original is re-supplied onto the platen glass with the second side facing downward, and the copying process for the second side is performed on the first side of the next copying material sheet on the machine side, resulting in a double-sided original. A single-sided copy of the second side is obtained. The document is ejected in the forward direction. As a result, the original is returned to the original placing table with the first side facing upward in the same way as when it was initially set.

If the first side of a double-sided original is to be loaded onto the 1δ original table with the first side facing down, the original is fed and ejected in the reverse order: forward feeding → re-feeding inverted → reversing ejecting. I will send it to you.

D. Double-sided original - double-sided copy mode The feeding and ejection of the original is the same as in item 0 above, and the copying process for the first and second sides of the double-sided original is performed using the same copy material sheet I on the machine side. A double-sided copy of a double-sided original can be obtained by sequentially performing the above steps on the first side and the second side.

In this way, image forming processes in various modes A to D can be automatically performed by equipping the circulation type automatic document feeding device of the image forming apparatus with all the feeding and discharging functions described in items 1) to 5) above. This is extremely convenient. However, on the other hand, the equipment itself inevitably becomes more complex, larger, and more expensive. Also, some users require automatic copying using an automatic document feeder, but for the time being, automatic copying will be limited to basic one-sided original copying, or this and one-sided original copying.
In many cases, it is sufficient if double-sided copying is possible. For such users, the above-mentioned all-feed rumor removal function 1
) to 5) have excessive functions and are uneconomical.

The present invention is directed to a circulating sheet feeding device of the above-mentioned type, which is suitable for users who only need to have a basic feeding/discharging function for the time being, but who later require various feeding/discharging functions. Users who have become like this, ha! To provide a device with a device configuration that can easily meet the needs of both users who require a device equipped with various feeding and discharging functions. 'With the goal.

That is, the present invention provides a circulating sheet feeding device that feeds a sheet set on a sheet stacking unit to a predetermined processing unit and returns the sheet to the sheet stacking unit. The main device has a sheet feeding/discharging mode between the same processing sections, which is normal feeding-normal discharging or reverse feeding-reverse discharging, and is detachable from the main device. When installed, the sheet returned from the sheet processing section of the main device is received, reversed, and re-feeded to the sheet processing section of the main device, or the sheet is returned to the main device without being reversed. The gist of the present invention is a circulating sheet feeding device characterized by having a two-device configuration, including a subdevice for returning and feeding a sheet to a stacking section.

A detailed explanation will be given below based on an embodiment of the apparatus shown in the figure. FIG. 1 is a longitudinal sectional front view showing a schematic configuration of an example of a copying machine B equipped with an automatic document feeder A as a circulating sheet feeder according to the present invention. Manuscript automatic (,!
4. Candy device A is arranged on the top plate of the machine casing of copying machine B.

(1) Copying machine B The copying machine of this example is a drum type electronic copying machine. The configuration of the copying machine itself is outside the scope of the present invention, and its image forming principles and processes are well known, so a brief explanation will be provided here. A platen glass 12 is fitted into a large window hole formed in the top plate of the copying machine housing, and a document is automatically fed to a predetermined position on the platen glass 12 by an automatic document feeder A, which will be described later. Then, the downward image surface of the set document is optically scanned from one end side to the other end side by the movable imaging optical system 12a through the platen glass 12, and the document image is displayed on the axis 13.
A slit image is exposed on the surface of a drum-type electrophotographic photoreceptor 13 (hereinafter simply referred to as drum) which is rotationally driven in the direction of the arrow about a.

Reference numeral 14 denotes a charger that uniformly charges the surface of the drum 13 positively or negatively, and by exposing the uniformly charged surface of the drum to a slit image of the original image, the re-drum surface corresponds to the original image. Latent images are sequentially formed on the static image 1. The latent image is then visualized as a toner image by the developing device 15.

Reference numeral 18 denotes a transfer material sheet cassette, and 19 a paper feed roller that feeds out each transfer material sheet P in the set. Once the clogging is detected, the pair of register rollers 20 and 20a are driven to rotate at a predetermined timing synchronized with the rotation of the drum 13, and the drum is introduced between the drum 13 and the transfer charger 16. The toner images on the 13 side are sequentially transferred onto the surface of the transfer material sheet.

The transfer material sheets that have passed through the transfer section are sequentially separated from the surface of the drum 13. The surface of the drum 13 from which the transfer material sheet has been separated is subjected to a process of removing contaminants such as residual toner after transfer by a cleaner 7, and is repeatedly used for image formation.

The transfer material sheet separated from the surface of the drum 13 is introduced into fixing devices 22 and 22a by a belt-type conveyance device 21 (paper path IIb). The transfer material sheet that has exited the fixing device 22 ψ 22a is delivered onto the delivery tray 27 via the path of paper bus ■b → delivery rollers 26 and 26a, or the paper path mb is delivered to the switch pack mechanism (hereinafter referred to as "switch pack mechanism" in the sequential feeding state). (abbreviated as SB mechanism)2
3 → Paper path IVb → SB mechanism 23 that failed to switch reverse feed →
The paper is delivered onto the delivery tray 27 via the paper path (b) -> delivery rollers 26 and 26a. Also, in case of double-sided copy mode, the first
The transfer material that has first received the image transfer on its surface side is transferred to the fixing device 22.
The paper is once introduced into the intermediate tray 24 (paper path Vb) in front of the image plane through the path from a to paper path mb to the SB mechanism 23 in the sequential feeding state to paper path b. Next, the transfer material is introduced into the paper path (b) by the re-feeding roller 25, and is passed through the register roller pair 20Φ20a→paper path 1. Drum 13 on path b
The second surface side is introduced between the drum 13 and the transfer charger 16, facing the surface of the drum 13, and the image is transferred to that surface. Next, the transfer material sheets are sequentially separated from the surface of the drum 13 and introduced into the fixing devices 22 and 22a through the paper path Ib.
Then, the paper is ejected onto the ejection tray 27 with the second side facing upward through the path of paper path ■b + ejection rollers 26 and 26a, or the sheet is switched from paper path mb to SB mechanism 23 in the forward feed state to paper path b to reverse feed. SB mechanism 23 → paper path b → delivery roller 2
The paper is discharged onto the discharge tray 27 along a path of 6φ26a with the first surface facing upward.

Reference numeral 32 indicates a photoelectric sensor for detecting the passage of the edge of the transfer material sheet, which is disposed at the front of the 5Bfi mechanism 23 in order to obtain a timing signal for switching the sequential feed. This is a photoelectric sensor for detecting the passage of the end of the transfer material, which is disposed in front of the roller 25 in order to obtain timing signals for feeding drive and drive stop.

(2) Automatic document feeder A This automatic document feeder A is comprised of a main device A1 and a sub device (original sheet reversing mechanism unit) A2 which can be freely attached to and detached from the main device according to the configuration of the present invention described above. Figure 1 shows the docking of the sub device A2 to the main device A1.
FIG. 2 is a cross-sectional view of the main device A1 with the sub-device A2 removed.

i, main device A1 11 years old original document mounting table; 2 is a feed belt drive roller; 2a is a feed belt driven roller;
is applied and is rotating in the direction of arrow C in the figure. 4
4a is a separation belt driving roller, 4a is a separation belt driven roller, and a separation belt 5 is placed between them, rotating in the direction indicated by the arrow in the figure. Feeding belt 3 and separation belt 5
As a result, a plurality of sheet-shaped originals placed on the original platen 1 are separated one by one from the lowest original and fed in the C direction. 6 is a conveyance roller, and 6a and 6b are rollers that are in pressure contact with the conveyance roller 6, respectively. Reference numeral 7 denotes a conveyor belt driving roller located near the left side of the platen glass 12 disposed on the top plate of the copying machine main body, and 7a denotes a conveyor belt driven roller located near the right side of the platen glass 12. A belt 8 is attached. The lower surface of this suspension belt 8 faces or contacts the upper surface of the platen glass 12 in close proximity. 10 is the original SB mechanism;
Reference numeral 11-1'la is a discharge roller that discharges the copied document onto the document table 1. Also, this discharge roller 1l-1
The document conveyance force of 1a is weaker than that of SB@structure 10. Therefore, even if it is reversed by the SB mechanism, it will not be a hindrance to conveyance.

The document is then stacked and set on the document placement table 1, and the document is placed on the feed belt 3.
The lowermost original of the stacked originals, which are separated by one sheet and fed in the C direction by the combined action of the separation belt 5, enters the paper bus Ia, and is sandwiched between the conveyance roller 6 and the roller 6a on the way, and then relayed. 8 ■] (The conveyor belt is conveyed by the conveyor belt and the platen is in a forward rotation state with respect to the lath 12) Subsequently, the sheet is conveyed from the left to the right over the platen glass 12 by the feeding force of the conveyor belt 8. Sensor 2 at the rear edge of the original
Passage of the 8th position is detected by the sensor 28, and the rotational drive of the conveyor belt 8 is stopped after a predetermined timer period has elapsed since then. This allows the original to be placed on the platen crow 12'.
+f+j' is automatically positioned at a predetermined position. When the original is positioned on the platen glass 12, the copying operation on the side of the copying machine main body B is started, and the copying of the downward image side of the original on the platen glass 12 is performed as explained in the above section (1). .

When the optical exposure scanning of the original set on the platen glass 12 is completed, the reverse rotation of the conveyor belt 8 is started based on the signal, and as a result, the original set on the platen glass 12 is moved in the above case. On the contrary, glass 12
The top is returned to the left and conveyed, and the paper lot ■a → between the discharge roller 6 and the roller 6b → *+ feeding state σSB mechanism 10 → paper path V
Through the path of the Ia+υl feed rollers 11 and ll'a, the stacked original f14 on the original platen 1 is returned and ejected with the downward surface on the platen glass 12 facing upward. When the leading edge of the document is detected by the sensor 30 during the return path 4'1', feeding of the next document, that is, the lowest document on the table 1''2 is started.゛That is, this main device A1 only has the function of performing the circular feeding and ejection of originals between the original placing table 1, which is a sheet placing part, and the platen crow 12, which is a sheet processing part, by reversing feeding and reversing υ1 feeding. It will be done.

Figures 3 and 4 show a top view and a side view of the separation mechanism of the main device A1. 60 is a partition plate that separates the original before exposure and the original after exposure. This partition plate 60 is supported by a fulcrum 62 on a partition plate arm 61. Also, 63 is a friction plate that is engaged with a gear 65 fixed to the shaft 4a of the separation belt driven roller 4a. A cage sandwiched between the arm gear 66 and the partition plate arm 61, the separation belt drive roller shaft 4' and the driven roller shaft 4a.
As the partition plate arm 61 rotates, a load is applied to the partition plate arm 61 in the direction of arrow G (FIG. 4). This facilitates the feeding of the original from the original placing table 1. Also, a roller 67 that receives the load of the partition plate arm 61 via the feed belt 3 is exposed. Reference numeral 70 denotes a hinge placed between the shaft 68 on the partition plate 60 and the shaft 69 on the partition plate arm 61, so that the line connecting the shafts 68 and 69 crosses the fulcrum 62 and moves in the direction of arrows E and F. The partition plates 60 are respectively moved. The outer periphery 71 of the partition plate 60 has a cam shape, and when the dividing plate 60 and the partition plate arm 61 rotate in the direction of arrow G, the partition plate 60 in the F direction. Reference numeral 73 denotes an optical sensor that detects rotation of the partition plate arm 61 in the G direction, and from this it can be determined that one cycle of document copying has been completed. - That is, the partition plate 60 is present immediately above the last page 9 of the original placed on the original placing table 1. When the last page is fed, the partition plate 60 comes into contact with the feeding belt 3, so
The frictional force therebetween rotates the partition plate 60 in the direction of arrow E, and the force of the spring 70 causes the partition plate 60 to be folded into a y-island as shown by the two-dot chain line in FIG. Here, since a load is applied to the partition plate arm 61 in the direction of arrow G by the friction plate 66, the partition plate arm 61
When 0 is folded, it starts rotating in the G direction. The feed heald drive roller 2 and the separation belt drive roller 4 each stop when the rear end of the original +f4 is detected 11 by the sensor 100 provided on the downstream side of the sheet path Ia. When the last page is fed, it will be rotated after rotation as indicated by the two-dot chain line in Fig. 4.
1 is detected by the sensor 73, the last page is returned to the exposure document mounting table 1, and the feeding heald drive roller 2 and the separation belt drive roller 4 are stopped until one cycle is completely completed, and then the second cycle is started. If the rotation is started on the first page, the partition plate 60 will be placed on the second page of the last page. Figure 5 is a cross-sectional rear view of the drive section of the main device A1. In the figure, 41 is a motor, and 42 is a motor pulley. In addition, bells I, 43 and 44 for transmitting drive to the conveyance roller 6, the rollers 6 pas a and 6b that are in pressure contact with it, and the D1 feed rollers 11 and 11a are attached to pulleys 45 and 46.
・The phone number is 47. Furthermore, 48 is a clutch that transmits drive from the motor 41 to the conveyance heald drive roller 7, and is capable of switching between forward and reverse rotation. 49 is a clutch that transmits the drive from the pulley 47 to the feed heald drive roller 2 and the split-rot drive roller 4. Further, a belt 51 for transmitting drive to a pulley 53 provided in the SB mechanism 10 is wrapped around the pulley 46 .

As described above, the drive section does not need to be separated and can be concentrated in one location.

11. Sub-device A2 The sub-device A2 has a document SB wall mechanism, its driving mechanism, a document sensor, etc. built into the housing 80. 91 is a sub-device mounting stand provided on the left side of the top plate of the machine casing of copying machine B; 93
is a main device/sub device consisting of a lower part of the side wall of the housing 92 on the mounting base 91 side that can be freely opened and closed around the shaft 94.
It is a sliding door plate.

The attachment and combination of the sub device A2 to the main device A1 is performed by the main device A.
The door plate 93 on the l side is opened and rotated upward about the shaft 94 to release the sub-device door plate 93, and the sub-device A2 is placed on the mounting table 91 with the front side closed.

Place the sub-device A2 toward the docking port, use the base 91 as a guide, and sufficiently push the sub-device A2 against the docking port to rub the sub-device A2. (The front side and both sides of the door plate are rotatably provided around a shaft 81 respectively.) The link member 82 is engaged with the sound emitting device 6 at both ends of the door plate opening/closing central shaft 94 on the main device Al side. Complete the installation by securing it to prevent it from coming off.

Reference numeral 9 denotes a document SB wall mechanism 1[a/
■a, va, ■a are the paper passes for the internal number of the sub device A2, and when the sub device A2 is attached and combined with the main device paper pass II
It is in communication with a.VIa. At 83t-, connect the M1 electric circuit plug to the front wall of the sub-device A2 by protruding it forward.
Copying machine B when sub device A2 is attached to main device Alt.
The sub-device A2 is connected to the side outlet 95, and the sub-device A2 is electrically connected to the NJI a11 circuit of the copying machine B1j.

Figure 6 is a cross-sectional rear view showing the drive section of sub-device A2 □
It is a diagram. In the figure, 84 is a coupler gear support plate which allows the shaft 85 to swing freely in both directions, and which is constantly urged to rotate in the 20 directions counterclockwise in the drawing by a biasing member (not shown), and 86 is a supporting plate for the shaft 85. It is a coupler gear that is pivotally connected to the plate. Sub device A2 to main device A1
When installed and combined, the force plug gear 86 or the main device Al
The gear 96 is provided coaxially with the pulley 46 of the side drive unit and engages with a gear 96 that rotates together with the pulley 46 while ensuring backlash. 87 is a relay gear rotatably supported by the shaft 85 of the coupler gear support plate 84 and meshed with the coupler gear 86; 88 is a pulley coaxially and integrally fixed to the relay gear; 89 is the pulley;
This is a timing belt suspended five times between the switch bank and pulley 952 of the B mechanism 9.

That is, when the sub-device A2 is attached to the main device A1, the driving parts of both devices are mechanically connected to each other via the gear 96 and the coupler gear 86.

(3) Various copying modes When only the main device A1 of the automatic document feeder A is used, single-sided copying or double-sided copying of a single-sided original can be automatically performed. Furthermore, when the main apparatus At is used with the sub apparatus A2 attached thereto, in addition to the above, single-sided copying of a double-sided original can be automatically executed.

i. Single-sided original - single-sided copy mode A plurality of single-sided originals are stacked and set on the original placing table l with the image side facing upward. The copy mode designation key (not shown) is pressed, and the copy start key (not shown) is pressed.

Then, as explained in section (2)-i above, the lowest one of the stacked originals on the original platen 1 will be placed on the platen glass 1.
The original is reversely fed to a predetermined position of No. 2 along a path of paper path Ia→I[a, and one-sided copying of the original is executed on the copying machine B side. When the optical scanning is completed, the original is returned to the paper path II by the reverse rotation of the transport belt 8.
The document is inverted and ejected onto the original stacked on the document placement table 1 along the route a→(2)a, and the next document is inverted and fed from the document placement table 1 side to the platen glass 12. On the copying machine B side, from the transfer unit 16 through the paper path mb to the fixing devices 22 and 22a.
The transfer material introduced into the next paper path ■b → delivery roller 2
The paper is discharged onto the tray 27 along the path 6.26a with the image surface facing upward.

By repeating the above operation as many times as the number of originals placed on the document tray 1, one set of one-sided copies from the one-sided original is ejected and placed on the output tray 27 in order from the last page. Ru. Copying a plurality of copies is carried out by setting the required number of copies using the operation section, and then repeatedly transporting the documents stacked on the document tray 1 in a circular manner the required number of copies.

ii. Single-sided original-double-sided copy mode A plurality of single-sided originals are stacked and set on the original placing table 1 with the image side facing upward. Press the copy mode designation key and press the copy start key.

Then, the feeding and ejection of the original between the original placing table l and the platen glass 12 is performed by the same reverse feeding and reversing transport as in the case of item i above.

On the copying machine B side, the transfer material that has undergone the image transfer on the first surface in the transfer section 16 is transferred to the fixed 'It device δ2 via the paper path mb.
2. Pass through 22a, then paper path mb → SB in feeding state
It once enters the intermediate tray 24 (paper path Vb) through the mechanism 23 → paper path ■b, and then is re-fed by the refeeding roller 25 and passes through the paper path ■b → register rollers 20 and 20a → paper path Ib. Then, the document is reintroduced into the transfer unit 16 and undergoes image transfer of the next document image onto the second side. Next, the transfer material passes through paper path mb → fixing devices 22 and 22a → paper path ■ b →
The paper is discharged onto the discharge tray 27 along the path of the discharge rollers 26 and 26a with the second surface facing upward. That is, double-sided copies in which images of two single-sided originals are copied on the front and back sides are discharged onto the tray 27.

The above-described operations are repeated for the number of originals placed on the original placing table, and one set of double-sided copies from the single-sided original are placed on the discharge tray 27 in order from the last page upward. Copying a plurality of copies is performed by setting the required number of copies using the operation unit, and then repeatedly conveying the stacked originals on the document mounting table the required number of copies.

rii, double-sided original-single-sided copy mode The sub-device A2 is attached to the main device A1 of the automatic document feeder. A plurality of double-sided originals are stacked and set on an original placing table 1. Press the copy mode designation key and press the copy start key.

Then, the lowest stacked original on the original platen 1 is reversely fed onto the platen glass 12 via the paper path Ia → paper path IIa, and one-sided copying of the downward side of the original is performed on the copying machine B side. be done.

From the transfer unit 16 through the paper path nb to the fixing devices 22 and 22a.
The transfer material introduced into the next paper path ■b → delivery roller 2
It is discharged onto the tray 27 along the route 6.26a.

On the other hand, after the optical scanning is completed, the document on the platen glass 12 enters the paper path I[a on the side of the sub-device A2 from above the platen glass 12 by the reverse rotation drive of the conveyor belt 12, and then the paper path ■
The paper is conveyed along the path a→SB mechanism 9 in the sequential feeding state→paper path ■a. Next, when the trailing edge of the document is detected by the sensor 29, the document is switched back by the SB mechanism 9 and passes from the paper path lVa to the paper path 2a, and then moves to the paper path Via on the main apparatus Al side. When the trailing edge of the document is detected again by the sensor 31, the SB mechanism 10 switches back and changes the paper path Vi.
The paper passes from a to the paper path ■a, and is sent onto the platen glass 12 again by the conveyor belt 8, which is rotating in the forward direction at this point, and is positioned at a predetermined position on the platen glass 12.
・It is done (reverse refeed). At this time, the side of the original opposite to the side that was copied first is facing down, and a one-sided copy of that image side is executed on the copying machine B side, and the copy is placed in the tray as in the previous case. 27.

Next, the document is sent backwards to the left of the platen glass by the reverse rotation of the conveyor belt 8 and enters the path ■a→IVa on the device A2 side, and when the trailing edge of the document is detected by the sensor 29, the SB mechanism 9 Paper pass Va→VIa after being checked back
The document is then returned to the document placement table l by the discharge rollers 11 and 11a (forward discharge), and is placed on the lowest paper surface of the stacked documents on the document table 1. The returned document is placed with the same side facing up as it was fed.

Further, in response to the document trailing edge detection signal from the sensor 29, feeding of the next document, that is, the lowest document placed on the table 1 is started.

By repeating the above operations for the number of originals placed on the original placing table, one set (one copy) of one-sided copies from the two-sided originals is ejected onto the output tray 27, and one cycle is completed. do.

When the desired number of copies is set using the operation section, the same operation is repeated until the predetermined number of copies have been completed, thereby obtaining the desired number of single-sided copies of the double-sided original.

Note that in order to realize the switch pack operation in the SB mechanisms 9 and 10, the trailing edge of the document must be in the SB mechanism 9 and 10 in the state immediately before the switch back operation is performed.
It can be achieved if you put your mind to it. Therefore, no driving force is required at the front edge of the SB mechanism. In other words, the front edge can be placed in an open state, and there is no need for a mechanism to cover the document size, allowing the apparatus to be provided as compactly as possible. Therefore, when switching pack, the leading edge of the original is SB.
In the mechanisms 9 and 10, the fish exposed to the outside are switch-packed.

1v. Double-sided original - double-sided copy mode The sub-device A2 is attached to the main device A1 of the automatic document feeder. A plurality of double-sided originals with the pages in the same order are stacked and set on a document mounting table l with the first page facing down or facing up. Press the copy mode designation key and press the copy star key.

Then, the feeding and ejection of the original between the original placing table 1 and the platen glass 12 is performed in the same way as in the case of item 111, by reverse feeding, inversion refeeding, and normal rotation ejection.

In addition, on the copying machine B side, the transfer material that has undergone the image transfer on the first side in the transfer section 16 is routed via the intermediate tray 24 in the same way as in the case of the single-sided original/double-sided copy mode in Section 11 above. The image is reintroduced into the transfer section 16 and subjected to image transfer to the second surface.

Next, the transfer material passes through the paper path mb and the fixing devices 22 and 22a, and enters the paper path mb through the fixing devices 22 and 22a. Here, when the trailing edge of the copy paper is detected by the sensor 32, it is switched back by the SB mechanism 23, and is ejected onto the ejection tray 27 by the ejection rollers 26 and 28a through the paper path from b to b. Ru.

At this time, the paper is ejected with the side copied later facing down. That is, a double-sided copy that is the same as the double-sided original is discharged to the discharge tray 27.

By repeating the above operations for the number of originals placed on the original platen, one double-sided copy is ejected from the double-sided Ig IA onto the output tray 27 in the same page order as the original. The cycle ends.

Once the desired number of copies is set using the operation unit, the same operation is repeated until the predetermined number of copies are completed, and the desired number of copies are placed on the output tray.
is obtained, and the originals are placed on the original table in the order of pages.

As described above, the present invention relates to a circulating sheet feeding device that has a main device equipped with only basic feeding and discharging functions, and a main device that can be attached to and detached from the main device. In addition to the basic feeding and discharging functions, we have adopted a two-device configuration with a sub-device that can add various variations of feeding and discharging functions, so users can use only the main device for the time being as needed. You may purchase and use only the sheet feeding device, you may purchase a sub-device afterwards and use it in combination with the main device, or you may use the main device with the sub-device from the beginning. It is selective and can be used economically.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional front view showing a schematic configuration of an example of a copying machine equipped with an automatic document feeding device as a circulating sheet feeding device according to the present invention, FIG. 2 is a sectional view of the sub-device separated state, and FIG. Figure 4 is a top view and side view of the document separation mechanism;
The figure is a cross-sectional rear view of the drive mechanism section on the main device side, and FIG. 6 is the same view as above of the drive mechanism section on the sub device side. A is the automatic document feeding device, A1 is its main device, A2 is its sub device, and B is the main unit of the copying machine. Patent applicant Canon Co., Ltd. Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] (1) In a circulating sheet feeding device that feeds a sheet set on a sheet stacking unit to a predetermined processing unit and returns the sheet to the sheet stacking unit, the device is the same as the sheet stacking unit. The main device has a sheet feeding/discharging mode between processing sections of normal rotation feeding - normal rotation discharge, or reverse feeding - reverse discharge, and is detachable from the main device and is attached to the main mounting. By doing this, the sheet returned from the sheet processing section of the main device ξ is received, the front side is reversed, and the sheet is re-feeded to the main device side sheet processing section, or the front side and back side of the sheet is reversed and the sheet is returned to the main device side. A circulating sheet feeding device characterized by having a two-device configuration, including a subdevice for returning and feeding sheets to a sheet placing section.