JP3197142B2 - Circulating original transport device and image forming apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circulating document feeder for feeding and placing a sheet document at a predetermined position of an image reading section.

[0002]

2. Description of the Related Art FIG. 1 shows an example of a conventional circulating document feeder.
3 is shown.

In FIG. 1, originals P stacked on an original tray 4 are sent out by a half-moon-shaped paper feed roller 5, separated one by one by separation / conveyance means 6, 38, and fed in the direction of arrow E. Then, it is carried in from the carry-in side B to the platen glass 3 of the copying machine 1 as an image forming apparatus. The document P to be carried in is conveyed to a predetermined position on the platen glass 3 by the wide belt 7 that rotates while contacting the platen glass 3. Reference numeral 213 denotes a light source that scans the set document P in the direction of arrow A to read an image, and 11 denotes a discharge roller that discharges the document P after image reading onto the document tray 4.

In FIG. 14, the original P after scanning the light source 213 of the copying machine 1 to the rear end 215 of the original P and reading the image is rotated by the reverse rotation of the wide belt 7 from the carry-in side B of the platen glass 3 to an arrow. Large roller 1 transported in A 'direction
0 and the rollers 12 and the discharge rollers 11 which are in contact therewith, switch back onto the unfed paper P on the document tray 4 and discharge it.

[0005]

However, in the above-mentioned circulating document feeder, the document is fed from the second feed roller side, and the sheet document after reading the image on the platen glass is placed in the document tray. In the paper feeding method in which the originals are stacked and placed on the upper originals, the discharged originals to be gradually discharged are stacked on the originals in the original tray. The drawback is that feeding and transporting the fed document becomes difficult due to the transport resistance due to the weight of the ejected document stacked on the unfed document, and the unfed document cannot be fed and transported stably. was there.

SUMMARY OF THE INVENTION The present invention relates to a circulating document in which a non-feeded document on a document tray is reliably separated from a discharged document discharged thereon, and the feeding of the non-feeded document by feeding means is ensured. It is an object to provide a transport device.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has an original tray on which a plurality of sheet originals are stacked, and a lowermost sheet original at the leading end of the original bundle on the original tray. Paper feeding means for feeding a sheet document in contact with the sheet, separating means for separating and feeding the fed sheet document one by one, and feeding means for feeding the document to a document reading position; In a circulating document feeder having a document discharge means for discharging a document onto the document tray, and a separating means capable of coming in contact with and separating from the document bundle on the document tray, the partitioning means comprises an unfeeded document. Is pressed against the paper feeding means, and the discharged original is distinguished from the unfed original.
A weight member for pressing an unfed original to the paper feeding means, and a partition member for distinguishing the discharged original from the unfed original, wherein the weight member and the partition member are coaxial with each other, and It is characterized by being able to move freely.

The weight member contacts the sheet document at a position facing the sheet feeding means, and the partition member contacts the sheet document at a position separated from the sheet feeding means.

[0009]

According to the above construction, when the number of image forming copies of a bundle of documents on the document tray is one or n, and when there are n circulation surfaces, the weight member and the partition member constituting the sheet document stopper are not fed. Each of them comes into contact with a bundle of originals (unfed originals). A weight member integrated with the rotation shaft presses the unfed document against the paper feeding means to increase the conveyance force of the sheet document by the paper feeding means, and a partition member swingably supported by the rotation shaft includes: The discharged original that comes into contact with the unfed original by its own weight and is discharged onto the unfed original is separated from the unfed original to be distinguished.

Since the partition member is swingably mounted on the rotating shaft, even if there is a slight deviation in the parallelism between the rotating shaft and the document tray, the partition member can be placed on the unfed original. By reliably contacting, it is possible to reliably perform a partitioning operation of a discharged original discharged onto an unfed original.

When the sheet document fed by the sheet feeding means is delayed in the separation / conveying means, the pressing force of the unfeeded document to the sheet feeding means by the weight member is increased, and the sheet feeding is delayed. The conveying force of the sheet document by the paper means is increased. When the pressing force of the weight member is increased, the partition member can swing relatively to the weight member supported on the same rotation shaft. Further, the occurrence of conveyance resistance due to this is suppressed, and the conveyance force to the delayed sheet document can be increased.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 12 shows an example of an image forming apparatus to which the circulating document feeder according to the present invention can be applied.

In the figure, reference numeral 900 denotes an upper cassette, and sheet materials P in the cassette are separated and fed one by one by the action of a separation claw (not shown) and a feeding roller 901, and are guided to a registration roller 906. . Reference numeral 902 denotes a lower cassette, and sheet materials P in the cassette are separated and fed one by one by the action of a separation claw (not shown) and a feeding roller 903, and are guided to registration rollers 906. Code 90
A manual feed guide 4 guides the sheet material P one by one to a registration roller 906 via a roller 905. Reference numeral 909 denotes a sheet stacking device (deck type),
An intermediate plate 909a that moves up and down by a motor or the like is provided.
The sheet material P on the sheet 9a is separated and fed one by one by the action of a feeding roller 910 and a separating claw, and is guided to a conveying roller 911.

Reference numeral 912 is a photosensitive drum, 913 is a reading optical system, 915 is a developing device, 916 is a transfer charger, 91
Reference numeral 7 denotes a separation charger, and these constitute an image forming unit 920.

Reference numeral 921 denotes a sheet material P on which an image has been formed.
922 denotes a fixing device, 923 denotes a conveying roller, and 925 denotes a flapper. The sheet material P on which an image has been formed is guided to a discharge roller 926 by a flapper 925, and is conveyed into a sorter 927. This sorter 927 has a non-sort tray 930a,
It has a sort bin tray 930b, a non-sort tray discharge roller 930c, and a sort bin tray discharge roller 930d, respectively, and the non-sort tray 903a and the sort bin tray 930b move up and down to sort the sheet material P one by one. A discharge tray may be mounted in place of the sorter 927.

Reference numeral 2 denotes an RDF which is a sheet conveying device, which includes a document tray 4, separating means 6, 38, and a return path 9.
31c, a discharge roller 11 and the like. The sheet document P is positioned one by one on the platen glass 3 by the automatic document feeder 2 and read by the optical system 913. Reference numeral 7 denotes a transport belt that rotates the document P forward (in the direction of arrow 960) to guide the document P to the platen glass 3, and discharges the sheet document P from the platen glass 3 by reverse rotation.

For one sheet original P placed on the platen glass 3, according to the set number of copies,
An image is formed on the photosensitive drum 912, and sheet materials P for the number of copies are fed from the cassette 900, 902 or the deck 909 each time an image is formed on the photosensitive drum 912. Image on photosensitive drum 912 and sheet material P
Is performed by the registration roller 916.

When the required number of copies are formed, the sheet document P is discharged from the platen glass 3, and the next sheet document P is positioned on the platen glass 3.
Hereinafter, the same operation is repeated.

In addition to the above-described automatic document feeder, a closed-loop circulating document feeder according to the present invention described below can be applied to the image forming apparatus main body 1.

Reference numeral 940 denotes an intermediate tray, which is used when an image is formed on both sides of the sheet material P or when an image is formed on one side of the sheet material P (multiple).
The sheet material P on which an image is formed is stocked. Reference numeral 941 denotes a conveyance roller, 942 denotes a conveyance belt,
943 denotes a flapper, 945 denotes a transport belt, and 946 denotes a transport roller. For double-sided copy,
The sheet material P is passed by the discharge roller 948 through the path 947.
To the intermediate tray 940. The image surface of the sheet material P faces upward. In the case of multiple copying, the sheet material P is guided to the intermediate tray 940 through the path 949. The image surface of the sheet material P faces downward.

The sheet material P stacked on the intermediate tray 940
Is a pair of auxiliary rollers 950 and 951 and a pair of forward / reverse separation rollers 9
By the action of 52, the sheets are separated one by one from below and fed again. The re-fed sheet material P is transported by the transport roller 95.
3, 955, 956, a roller 911, and a registration roller 906 are guided to an image forming unit 920.

In accordance with the number of copies set for one sheet original P placed on the platen glass 3, first, single-sided copies are made and they are stacked on the intermediate tray 940. After that, the sheet document P on the platen glass 3 is turned upside down and guided again on the platen glass 3,
This image is read for the number of copies. The read image is formed on the sheet material P re-fed from the intermediate tray 940 every time the image is read. They are sorted by the sorter 930 in page order.

On the other hand, the sheet document P is fed to the automatic document feeder 9.
There is also a method in which only one copy is created each time one round is performed by the method described above. According to this method, even when a plurality of copies are made, a copy group with the same page order is obtained in order, so that a necessary number of copies can be obtained separately without the sorter 930. When making a double-sided copy in this manner, both sides of one sheet original P are continuously read, copies are continuously made on the front and back of the sheet material P and discharged, and then the same is applied to both sides of the next sheet original P. By repeating this process many times, a divided double-sided copy group can be obtained.

In FIG. 1, a sheet material conveying device R
The DF (circulating document feeder of the present invention) 2 has a document tray 4 above, and a wide belt 7 wound around a drive roller 36 and a turn roller 37 is disposed below the document tray 4. The wide belt 7 is in contact with the platen glass 3 of the copying machine main body 1, and conveys the sheet document P placed on the document tray 4 and places it on a predetermined position on the platen glass 3. Then, the sheet original P on the platen glass 3 is carried out onto the original tray 4.

In the document tray 4, a pair of width direction regulating plates 33 are slidably arranged in the width direction of the sheet document P, and the width direction of the sheet document P placed on the document tray 4 is adjusted. Regulate the stability of the sheet original P during feeding,
The consistency at the time of carrying out onto the document tray 4 is ensured. A jogging mechanism is built in one of the width direction regulating plates 33, and the sheet documents P conveyed out onto the document tray 4 are pressed one by one against the document reference guide 33,
Consistency is further enhanced. Further, the document tray 4 can be swung about the swing center 40 between the positions shown in FIGS.

Adjacent to the document tray 4, there is provided a half-moon-shaped paper feed roller 5 as a paper feed / transport means and a stopper 21 which moves up and down by a stopper solenoid.
The sheet document P when set on the document tray 4 is restricted by the protruding stopper 21 and cannot be advanced downstream. The stopper 21 also serves as a sheet bundle transfer unit described later.

Then, copy conditions are input at the operation unit of the copying machine 1 as an image forming apparatus, and a start key (not shown) is input.
When the is pressed, the stopper 21 sinks and the path of the sheet document P is opened, and the sheet document P is fed by the paper feed roller 5 and advances to the downstream. At this time, the partition member 22 connected to the partition member motor built in the other width-direction regulating plate 33 as the document reference guide on the document tray rotates on the topmost sheet document P and runs over the unprocessed sheet. Distinguish between manuscript and processed manuscript.

Downstream of the stopper 21, there is provided a first separation unit including a transport roller 38 and a separation belt 6, which constitute a separation unit. The first separation unit rotates in the direction of the arrow and advances from the document tray 4. The sheet document P is separated one by one and transported further downstream.

A weight 20 is provided above the stopper 21 so that the number of sheet documents P on the document tray 4 is small and the sheet documents P can be separated only by the feeding force of the paper feed roller 5. When the sheet cannot be advanced to the position, the sheet is moved downward by the weight solenoid, and the sheet original P is sandwiched between the sheet and the sheet feeding roller 5 to improve the feeding force of the sheet feeding roller 5.

A document feed path (a), (b), and (c) is formed from the separation sections 6 and 38 to the platen glass 3 (see FIG. 4).
(B) and (c) are bent and connected to the conveyance path on the platen glass 3 to guide the sheet document P onto the platen glass 3. In the vicinity of the paper feed roller 5, entrance sensors 23a and 23b, which are transmissive optical sensors for detecting the presence or absence of a sheet document P placed on the document tray 4, are arranged.

A large roller 1 is located on the left side of the main body of the RDF 2.
A document discharge path (e) and (f) extend from the platen glass 3 around the outer periphery of the large roller 10 and above the document tray 4 (see FIG. 4). Further, a document reversing path (E) for reversing the front and back of a two-sided document by branching from above the large rollers 10 of the document discharge paths (E) and (F) is configured (see FIG. 4).
The downstream portion of the document reversing path (e) is the document feeding path (b).
And come to join. A relay roller 44 and a paper discharge roller 11 are provided on the downstream side of the document discharge path (f). The sheet document P conveyed through the document discharge paths (e) and (f) is placed in a document tray. 4 is conveyed to the uppermost portion of the document bundle P on the upper side.

The wide belt 7 disposed above the platen glass 3 conveys and places the sheet document P at a predetermined position on the platen glass 3, and is carried out of the platen glass 3 after reading the image. The above document feeding path (a),
A feeding roller 9 is provided at the confluence of the document reversing path (e) and (b) and (c). The feeding roller 9 forms a loop on the reached sheet document P to form a sheet. The skew of the document P is prevented. Near the upstream of the feed roller 9,
Paper feed sensors 25a and 25b, which are transmission type optical sensors for detecting the front end and the rear end of the sheet document P, are provided.
The sheet document P that has passed through any one of the document feeding paths (a), (b), (c) and the document reversing path (e) can be detected.

Downstream from the feed roller 9, registration sensors 39a and 39b, which are transmission type optical sensors for detecting the rear end of the sheet document P, are provided. Below the large roller 10 in the document discharge paths (e) and (f), reversing sensors 26a and 26b, which are transmissive optical sensors for detecting the sheet document P carried out from the platen glass 3, are provided. Further, in the document discharge path (f) between the large roller 10 and the paper discharge roller 11, the passage of the sheet document P passing through the document discharge path (f) and carried out onto the document tray 4 is prevented. Discharge sensors 27a and 27b, which are transmissive optical sensors for detection, are provided.

A reversing flapper 34 for switching the path is provided at a portion branched from the document discharging paths (e) and (f) to the document reversing path (e). When the switch is turned off, the path is switched by swinging between the solid line position and the chain line position in the figure.

Further, on the right side of the main body of the RDF 2, a second document separating means for conveying a sheet document from the right end of the platen glass to an image reading portion on the platen glass 3, a second document feeding path (h), (I) and (nu) (see FIG. 4).

The document tray 4 swings with the upper and lower positions shown in FIGS. 1 and 2 in conjunction with the vertical swing operation of the swing arm. As shown in FIGS. 2 and 3, when the document tray 4 is at the lower limit position, a second half-moon-shaped sheet feed roller (sheet feed / transport unit) 8 and a second separation unit are formed adjacent thereto. A conveying roller 15 and a separation belt 14 are disposed, and separate the sheet documents P that have been advanced from the document tray 4 by rotating in the direction of the arrow, one by one, and further conveyed to the downstream side.

In FIG. 5, the stopper 21 and the short arm 41 integral therewith are rotatable about the support shaft 12, and the pin of the short arm 54 is engaged with the recess of the operating member 13. The stopper 21 is turned to the position indicated by the dashed line by turning the operating member 13 clockwise. The operating member 13, which is pivotally supported at the intermediate portion by a support shaft so as to be rotatable about a support shaft 59 b, is urged counterclockwise by a tension spring 42, and the rotation is regulated by the stopper 21. . A connecting member 43 is provided at the lower end of the operating member 13.
Is connected to the stopper solenoid 24 via the.

The document tray 4 has an upper limit position or a lower limit position depending on the size of a document placed on the tray and input conditions of the image forming apparatus. When the tray 4 reaches the lower limit position, the above-mentioned stopper 21 of the tray 4 conveys the sheet document P placed on the tray 4 to the second separating means 14 and 15 side by a certain distance in a bundle.

The sheet documents P conveyed in a bundle are always conveyed to a position where paper presence is detected by transmission type optical sensors 28a and 28b which are arranged near the upstream of the second separating means and detect the presence or absence of sheet documents. (See FIG. 3). When the bundle conveyance is completed, the sheet document stopper 19 is configured to be placed on the sheet document P.

Downstream of the second separating means 14, 15,
A second feeding roller 16 is provided, and the second feeding roller 16 forms a loop on the reached sheet document P to prevent skew of the sheet document P. In the vicinity of the upstream side of the second feed roller 16, second paper feed sensors 30a and 30b, which are transmission type optical sensors for detecting the front end and the rear end of the sheet document P, are provided. Further, a relay roller 17 is provided on the downstream side, and a transmission-type optical sensor 18 for detecting the leading end position of the sheet document P is provided in the second feeding path (N).
a and 18b are provided. This tip sensor 18a,
By 18b, timing control of a sheet material on which an image is formed in the image forming apparatus is performed.

When the lowermost sheet is transported by the rotation of the second transport roller 15 until the lowermost sheet is separated, (1) the number of image forming copies is reduced to one by the input key to the image forming apparatus 1.
When the sheet is set as a copy, the sheet original stopper 19 (the partition member 19a and the weight member 19b) remains mounted on the sheet original P as shown in FIG.
To prevent the discharged sheet original from entering the second separation section.

The sheet original stopper 19 is provided on the rotating shaft 3.
Two weight members 19a fixed to the first shaft member 1 and two parallel members 32 fixed to the rotating shaft 31 are used to separate the two partition members 19a swingably (see FIG. 6) with an appropriate play angle. (FIG. 6)
reference). As shown in FIG. 7, the partition member 19a is located at a position facing both ends of the document tray 4, and the weight member 19b is located above the second paper feed roller. The partition member 19a is formed with a keyway 19a that holds the parallel pin 32 so as to be movable.

The partition member 19a and the weight member 19b
The operation of the second sheet feed roller 8 and the document tray 4 is as follows: (a) The sheet document stopper 19 descends on the sheet document P stacked on the document tray 4 and the sheet document P is The sheet document P is pressed by the second paper feed roller 8 and fed, and is separated one by one by the separation and transport units 14 and 15. Further, the discharged original is stopped by the partition member 19a which comes into contact with the sheet original P, and is distinguished from an unfed original.

(B) At this time, the fed sheet original P
When the sheet document does not reach the separation sensor 29 even after a predetermined time has elapsed after the start of feeding, the downward urging force of the sheet document stopper 19 increases (hereinafter referred to as “retry”), and The conveying force is increased by rotating the solenoid to rotate the shaft 31. As a configuration for avoiding this retry, it is conceivable that the number of stacked sheets in which a feeding failure occurs is checked in advance by an experiment, and the pressing force is increased immediately before reaching the number. By doing so, there is no loss time for retry.

After completion of the moving image reading at a predetermined position, the sheet document P is discharged onto the document tray 4 by a discharge roller (document discharge means) 11. At this time, there is at least one sheet document on the document tray 4 and the two partition members 19a are
Each of the weight members 19b is attached to the bundle of sheet originals by its free weight by a rib at its free end because it is swingably attached to the rotation shaft 31 and is in contact with the sheet original bundle by its own weight (see FIG. 3). In contact.

At the time of a retry operation in which the downward urging force of the sheet original stopper 19 is increased, the stopper 19 does not move when the sheet original stopper 19 is at the lowermost limit state, but the lower urging force increases and the other than the lowermost lower limit. At this time, the sheet is lowered to the lowermost state, and the conveying force is increased by pressing the sheet document bundle.

As shown in FIG. 3, the stopper 21 serves as a sheet bundle transfer means for transferring the sheet document P to the second separation unit 1.
In this configuration, the sheet is transported to positions 4 and 15 and returns to the initial position after the transport. Each time a sheet document is discharged from the discharge roller 11 onto the document tray 4, the stopper 21 pushes the rear end of the sheet document toward the second separation side 14, 15, and the sheet document P on the document tray 4 is pressed. The alignment in the transport direction is improved (FIG. 3).

(2) When the number of image forming copies is set to n by the input key on the image forming apparatus 1 (one sheet of the document is n
In the case of circulation; the sheet original stopper 19 is shown in FIGS.
As shown in (1), the sheet document is retracted upward until (n-1) circulation, and when the first sheet document of the n-th circulation is re-stacked on the document tray 4, the sheet document stopper 19 is set to the sheet document stopper 19. The first sheet document is stacked on the document and restricts the document from entering the second separation section.

The sheet document stopper 19 is constructed and arranged as described above, and its relative position and operation state are as follows: (a) before the sheet document is completely circulated (n-1); Sheet document stopper 1
9 presses the sheet document bundle on the document tray 4 for a predetermined time to increase the conveying force, and then stands by again above.

(B) After the sheet document has been circulated (n-1); the sheet document stopper 19
Functions similarly to (b).

At this time, as shown in FIG. 3, the stopper 21 conveys the sheet document P to the second separating sections 14 and 15 and returns to the initial position after the conveyance. Also, each time the sheet document is discharged from the paper discharge roller 11 onto the document tray 4, the stopper 21 pushes the rear end of the sheet document toward the second separating portion, and the sheet document P on the document tray 4 is conveyed. The direction consistency is improved (FIGS. 8 and 9).

At the end of n circulation, the leading end of the sheet document P is regulated by the partition member 19a of the sheet document stopper 19 as shown in FIG. Thereafter, the document tray 4 moves upward and stops at the upper limit position.

As described above, by allowing the weight member and the partition member to function independently on the same axis, it is possible to reliably partition the unfed original and the discharged original by the partition member. However, the conveyance force at the time of paper feeding by the paper feeding roller is not reduced. In both the pressed state and the normal state, the partition member 19a is placed parallel to the upper surface of the sheet depending on the degree of freedom.

The partition member 19a and the weight member 1
The number of 9b may be one at a time, three at a time, or the number is not limited to two at a time.

<Other Embodiment> Next, FIG. 11 shows a second embodiment of the present invention.

In the above embodiment, the pivot shaft 31 is swingably attached to the pivot shaft 31 using the parallel pin 32. In the present embodiment, however, a hole is formed in the pivot shaft 31 in the opposite manner.
A spring pin 35 is provided on the partition member 19a and fitted into the hole of the rotating shaft 31 with play.

The weight member 19b does not need to be fixed to the support shaft 31, but may have a certain degree of freedom. However, the degree of freedom of the weight member 19b is in a range smaller than the degree of freedom of the partition member 19a. Also,
The weight member may be attached to the support shaft 31 via a friction member, a torsion coil spring, or the like, and the weight member may slip with respect to the support shaft when a certain area or more is added. The same applies to the partition member.

[0059]

As described above, according to the present invention,
Even if there is a slight deviation in the parallel accuracy between the document tray and the rotation axis, the partition member should be brought into proper contact with the unfed document,
It is possible to reliably distinguish between a discharged original discharged on an unfed original and an unfed original.

Further, by increasing the pressing force of the unfeeded original by the weight member to the paper feeding means, the conveying force of the unfeeded original can be increased, and when the pressing force of the weight member is increased, the partition member Swings the rotation shaft and does not contribute to the pressing of the unfed original, so that the conveying force of the paper feeding means can be increased without being hindered by the partition member, and the discharged original can be reliably partitioned. In addition, it is possible to suppress a reduction in the conveying force of the sheet feeding unit.

[Brief description of the drawings]

FIG. 1 is a vertical sectional side view of a circulation type document feeder according to the present invention.

FIG. 2 is a vertical cross-sectional side view of the circulating document feeder showing a state in which a sheet document is conveyed in a bundle.

FIG. 3 is a vertical cross-sectional side view of the circulation type document conveying device showing a state in which a sheet document is conveyed in a bundle.

FIG. 4 is a vertical sectional side view of the circulation type document feeder showing a sheet path.

FIG. 5 is a vertical sectional side view showing a main part of the document tray.

FIG. 6 is a longitudinal sectional side view showing a main part of a sheet document stopper portion and a separation portion.

FIG. 7 is a plan view of the apparatus of FIG. 6;

FIG. 8 is an operation diagram of the circulating document feeder.

FIG. 9 is an operation diagram of the circulating document feeder.

FIG. 10 is an operation diagram of the circulating document feeder.

FIG. 11 is a longitudinal sectional side view of a main part of a partition member according to a second embodiment of the present invention.

FIG. 12 is a vertical sectional side view of an image forming apparatus to which the circulating document feeder of the present invention can be applied.

FIG. 13 is a longitudinal sectional side view showing an example of a conventional circulating document feeder.

FIG. 14 is a diagram showing the same operation.

[Explanation of symbols]

P sheet original 1 copier (image forming apparatus) 2 RDF (circulating original transporting apparatus) 3 platen glass 5 first paper feeding roller 8 second paper feeding roller (paper feeding means) 6, 38 first separated transport Unit 7 Conveyor belt 11 Discharge rollers (document discharge means) 14, 15 Second separation / conveyance unit 19 (19a, 19b) Sheet document stopper (partition means) 19a Partition member 19b Weight member 21 Stopper 31 Rotation axis 32 Parallel Pin 35 Spring pin 920 Image forming unit

────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Chiaki Nagata 430-1, Kobayashi, Masuho-cho, Minamikoma-gun, Yamanashi Pref. (72) Inventor Masahito Akiyama 430-1, Kobayashi, Masuho-cho, Minamikoma-gun, Yamanashi Pref. 58) Field surveyed (Int. Cl. ⁷ , DB name) B65H 85/00 B65H 83/02 G03G 15/00 107

Claims (5)

(57) [Claims] An original tray on which a plurality of sheet originals are stacked; sheet feeding means for feeding a sheet original in contact with the lowest sheet original at the leading end of the original bundle on the original tray; Transport means for separating and transporting the read sheet documents one by one and transporting them to a document reading position; document discharging means for discharging the sheet documents after reading the document onto the document tray; A separating unit that can freely contact and separate from the original bundle, wherein the separating unit presses the unfed original to the feeding unit and distinguishes the discharged original from the unfed original. A sheet document stopper, the sheet document stopper comprising: a weight member for pressing an unfed document against the paper feeding unit; and a partition member for distinguishing the discharged document from the unfed document. The partition member there coaxially circulation type document feeder, characterized in that move freely with each other. 2. The apparatus according to claim 1, wherein said weight member contacts said sheet document at a position facing said sheet feeding means, and said partition member contacts said sheet document at a position separated from said sheet feeding means. 4. The recirculating document feeder according to 1. 3. The recirculating document according to claim 1, wherein the weight member increases the pressing force of an unfed document to the sheet feeding device when the separation and conveyance by the separating and conveying device is delayed. Transport device. 4. The sheet document stopper abuts on a document bundle when the number of image forming copies on the document tray is one, and when the number of image forming copies is n, the sheet document stopper is n-1. 2. The circulating document feeder according to claim 1, wherein the document is retracted to a position separated from the document bundle and abuts on the document bundle when feeding the nth separation. 5. A circulating document feeder according to claim 1, further comprising an image forming section for forming an image corresponding to a document image of a sheet document fed by the circulating document feeder. An image forming apparatus comprising: