JPH06115830A - Circulation type automatic document transport device - Google Patents

Abstract

PURPOSE:To stabilize delimiting operation by providing a delimiting means having a delimiting lever to divide a document fed from a document loading part from a document returned to the document loading part from a discharging means in the vicinity of the end part on the document side, and moving the delimiting through a specified route. CONSTITUTION:In an automatic document transport device 300 having a document loading part provided with an endless feeding belt 311, a push-up means 314 is arranged on the upper stream side in the vicinity of the side end part of the feeding belt 311, and a delimiting means 315 for the number of copies is arranged on the lower stream side. The delimiting means 315 is provided with a delimiting lever 315A to be moved right and left by action of a solenoid SL3 through a swing lever 315C, the pin 314F on the middle part of the lever 315A is guided with a D-shaped cam groove part 315J, and hence the extreme end part of the lever is moved through a specified route. The push-up means 314 is provided with a push-up lever 314A to be elevatably moved by action of the solenoid so as to push up the delimiting lever 315A at a necessary time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a recording apparatus such as an electrophotographic copying machine or an automatic document feeder in an image reading apparatus, and more particularly to a single-sided or double-sided recording original loaded on an original placing portion. Separate the sheets and feed them to the image reading unit,
The present invention relates to a circulating automatic document feeder having a document feeding mode (RDH) and a double-sided document reversing feeding mode (R-RDH), which has a function of returning the read document to the document placing portion again and feeding it repeatedly.

[0002]

BACKGROUND OF THE INVENTION As a device capable of efficiently feeding an image-recorded document to a recording device such as an electrophotographic copying machine or a recorded image reading device, even in an unmanned state, an automated document conveying device ( ADF) has already been provided.

Further, as a copying machine capable of copying each image of an original (double-sided original) having recorded images on the front and back sides and one side or both sides of the recording paper, and an image reading device capable of reading and recording the images, the ADF is provided with front and back sides of the original. An automatic document feeder (RADF) equipped with a reversing function has been put into practical use.

Further, the originals stacked on the original placing portion are separated one by one and automatically fed on the platen glass of the copying machine, and the originals after the exposure processing on the platen glass are again placed on the original placing portion. A circulating automatic document feeder (RDH) that can be returned and repeatedly processed has also been proposed.

This circulating automatic document feeder (RDH)
Makes copies one by one in one cycle, and circulates the original for the number of copies.

Further, recently, the present applicant has also provided a circulating automatic document feeder (R-RDH) in which a document front and back surface reversing mechanism is added to the above RDH (Japanese Patent Application No. 63-20228).

These circulating automatic document feeders (RDH,
R-RDH (hereinafter referred to as RDH device) enables high-speed continuous copying and quick page alignment of copied recording paper, and is connected to a finisher device for stapling and punching the recording paper for recording and final processing. Can be completed unattended.

In such an RDH apparatus, a plurality of originals, which are stacked with the front side of the originals facing upward on the original placing section, are fed one by one from the lowermost layer to the processing section (platen glass surface) in the feeding section. It is a bottom feed top return system that separates and conveys toward the bottom.

[0009] Such a bottom-feeding top-returning RDH
In the apparatus, when the document is fed out, problems such as the disorder of the document image due to dirt and rubbing on the document front and back surfaces caused by friction between the document front and back surfaces occur. In particular, in the case of a pencil-written manuscript, the manuscript stains due to the above problems are remarkable.

As a means for solving the above problem, Japanese Patent Publication No. 56
The top feed / bottom restack type RDH device disclosed in Japanese Patent No. 37536 has been proposed. In this method, the processed sheet is inserted from the lower side of the stack sheet by the cyclically moving stack lifting means for lifting the sheet.

The sheet storing and feeding apparatus disclosed in Japanese Patent Laid-Open No. 3-205273 discloses a sheet feeding and feeding apparatus for an RDH apparatus. The vertical pressing member is arranged at the position.

[0012]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
-In the automatic document feeder having the RDH function, a separating means is required to separate a document stack pre-loaded on the document placing part and a document which is unloaded from the image reading part and reloaded on the document placing part. And

The separating means in the conventional bottom-feeding-up / returning-type RDH apparatus is a simple lever for lightly pressing the upper surface of the document stack. However, RD of top feeding and bottom returning method
In the H-apparatus, a separating means for moving forward and backward must be provided at the bottom layer of the document stack. For this reason, the separating means may interfere with the document feeding means of the document placing section and the document conveyed on the document placing section. Particularly in an RDH device that circulates a document at high speed, it is necessary to stabilize the document separating operation.

[0014]

SUMMARY OF THE INVENTION The present invention solves various problems in the conventional automatic document feeder as described above, and in an RDH device of the upper feed bottom return type, the last page of the document being circulated and conveyed. It is an object of the present invention to provide an automatic document feeder which allows a device for entering or retracting into and separating a document to reliably operate without interfering with document transportation.

The circulation type automatic document feeder of the present invention which achieves the above-mentioned object, has a document placing portion on which a plurality of documents can be stacked and one of the plurality of documents stacked on the document placing part. Paper feeding means for separating and feeding the sheets one by one and feeding them to the image reading section, conveying means positioned downstream of the paper feeding means for conveying an original to the image reading section, and downstream of the image reading section in the original conveyance direction. In the circulation type automatic document feeder of the document top feed bottom returning system, which comprises an ejecting unit which is located on the side of the document and is discharged from the conveying unit to return the document to the lowermost layer of the stacked document on the document placing unit,
Separating means for distinguishing between the original fed from the original placing section and the original returned from the ejecting section to the original placing section is provided near the end on the original side, and the separating lever of the separating means is provided. A first operation in which the front end portion retreats from the first position above the end of the stacked document side to the second position outside the end of the document side;
It is configured to be movable by the second operation of advancing from the position of 3 to the third position of the bottom of the document bundle on the document placing portion and the third operation of urging the document bundle partially upward. It is characterized by that.

Further, the circulation type automatic document feeder of the present invention has a partitioning lever having a partitioning lever for distinguishing between the document fed from the document placing section and the document returned from the discharging means to the document placing section. Means and push-up means for raising the tip of the separating lever are provided in the vicinity of the end portion on the document side, and the tip portion of the separating lever that has entered the bottom portion of the document stack on the document placing portion is the It is characterized in that the document side edge is raised by a predetermined amount by the driving force.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the automatic document feeder according to the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is an overall configuration diagram of a copying machine equipped with an automatic document feeder. 100 is a copying machine main body, 200 is a paper feeding unit (PFU device), and 300 is a circulation type automatic document feeder (RDH device). ), 400 is a copying paper post-processing device (finisher (sorter with stapler device, etc.) hereafter referred to as FNS device).

The copying machine main body 100 includes a scanning exposure unit 110, an image forming unit 120, a paper feeding unit 130, a conveying unit 140, a fixing unit 150, a paper discharge switching unit 160, a plurality of paper feeding cassettes 170, and copy paper for double-sided copying. It is composed of a re-feeding device (ADU device) 180.

In the figure, the alternate long and short dash line indicates the conveyance path of the copy paper P. After the copy paper P stored in the paper feed cassette 170 or the paper feed unit (PFU) 200 at the bottom of the copying machine main body 100 is image-formed by the image forming unit 120, the transport unit 140, the fixing unit 150, and the paper discharge unit. The main route accommodated in the FNS device 400 via the switching unit 160 and the copy paper P branched from the paper discharge switching unit 160 are temporarily stocked in the ADU device 180, and then re-fed to the copying machine main body 100. The circulation route to the paper feeding unit 130.

FIG. 2 is a sectional view of the automatic document feeder 300 mounted on the upper portion of the copying machine main body 100. The automatic document feeder 300 to which the present invention is applicable conveys a plurality of originals (single-sided original or double-sided original) from the original placing section 310 to the exposure section of the platen glass 111 of the copying machine main body 100,
It is provided with various functions such as a circulation type RDH device, an R-RDH device, an ADF device, an R-ADF device, etc., which conveys again onto the document placing section 310.

The automatic document feeder 300 includes a document placing section 310,
Feeding unit 320, intermediate conveying unit 330, conveying unit 340, paper discharge reversing unit 350
It consists of

When the original stack D is placed on the original placing portion 310, the presence or absence of the original is detected by the original set detection sensor (zero original detection sensor) S1, and the ADF mode is displayed on the control panel of the copying machine main body 100. Is displayed. When the document stack D is set at a predetermined position, the document size (B5 to A3) is detected by the document size sensor S2 and input to the control unit of the copying machine main body 100.

A movable pressing plate 317 is swingable around a swing shaft 317A on the leading end side of the document feeding section 310 on the downstream side of document feeding. A drive plate 319 is screwed to the swing shaft 317A so that it can swing integrally. Further, an elastically deformable member (for example, a torsion spring) 317 is attached to the swing shaft 317A.
B is wound, and the drive plate 319 can be pressed at both ends thereof and the movable pressing plate 317 can be pressed at the center thereof.

The actuator portion provided on the drive plate 319 has a pressing home position sensor S fixed to a fixed bottom plate.
The optical path of 3 is turned on and off, and the home position of the drive plate 319 is detected.

FIG. 3 is a perspective view of an essential part of the document placing section 310. The wide feeding belt 311 which is loaded with the document D and supported and is rotatable is an endless belt wound around two axes of a driving roller 312A and a driven roller 312B.

FIG. 4 is a perspective view of the feeding belt 311. One end of the feeding belt 311 is joined by a joint 311A to form a loop. The other end of the belt 311 forms a tongue-shaped holding piece portion (gripper portion) 311B extending outward from the seam portion 311A. The feeding belt 311 is formed of a cloth belt coated with resin, a polyethylene terephthalate (PET) film, or the like. The inner surface of the sandwiching piece 311B of the feeding belt 311 and the outer surface of the belt (between A and B in FIG. 4) are roughened so as to have a high friction coefficient, and the other outer surface of the belt (B in FIG. 4). (Between C and C) forms a low friction coefficient smooth surface. 31
Reference numeral 1C is a detection hole formed in a part of the belt 311, and the home position of the feeding belt 311 is detected by the reflection type sensor S13 for detecting the home position of the feeding belt 311. The stop position of the sandwiching piece 311B is controlled.

In FIG. 3, an electromagnetic brake BRK2 and an electromagnetic clutch CL4, which are connected to the discharge motor M3 of the drive source, are provided at the rotary shaft end of the drive roller 312A. A fixed plate 313 is fixedly provided inside the feeding belt 311 between the drive roller 312A and the driven roller 312B. The fixed plate
313 supports the document bundle D on the feeding belt 311 by placing it on a flat surface.

Reference numeral 315 is a separating means for separating a bundle of originals stacked on the feeding belt 311 from a bundle of originals circulated after the reading process and placed at the bottom of the stack of stacked originals. The separating lever 315A of the separating means 315 is spring-biased, and is moved up and down by the solenoids SL3 and SL4, and is driven forward and backward in a direction orthogonal to the sheet feeding and obliquely downward driven.

In 311D, the separating lever 315A is a feeding belt.
A cutout portion provided on the side of the feeding belt 311 for retracting below 311.

The original stack placed on the original placing section 310 is stacked on the feeding belt 311 and a movable pressing plate 317 which will be described later, and the width stopper plate 316 for restricting the original stack in the original width direction by one side base. At the same time, the leading edge of the original is brought into contact with an original leading end stopper 318, which will be described later, and aligned and placed. At this time, the separating lever 315A is pressed and lowered by the weight of the document stack, and lightly pushes up the lowermost layer of the document stack. Further, the swingable paper pressing lever 310Z provided on the upstream side of the separating lever 315A in the document conveying direction is for assisting the returning document to be surely inserted under the document stack, and the document surface is supported by its own weight. Lightly press. The paper pressing lever 310Z is also effective for stabilizing the operation of the separating lever 315A when carrying curled paper or a small number of originals.

FIG. 5 is a front sectional view of the document placing portion 310 and the feeding portion 320, FIG. 6 is a plan view of the separating means 315, and FIGS.
FIG. 6 is a side view showing the operation of the separating means 315.

In these figures, the feeding belt 311
A separating means 315 and a pushing-up means 314 are fixedly provided on one fixed side plate 310A that axially stops the driving roller 312A and the driven roller 312B that rotate. That is, the pushing-up means 314 is provided near one side end of the feeding belt 311 and on the upstream side in the feeding direction.
However, a copy number separating means 315 is fixedly provided on the downstream side of the arrow.

A solenoid SL3 is fixed to the lower portion of the substrate 315B of the separating means 315, and the solenoid SL3 is fixed.
The lower end of the swing lever 315C is pin-connected to one end of the plunger SL3A. The swing lever 315C is provided on the substrate 3
It can swing around a fulcrum shaft 315D planted in 15B and is urged in one direction by a spring 315E. The upper end of the swing lever 315C has a separating lever 315A and a pin 315F.
Are bound by. Separation lever 315A has pin 315F
The weight 31 that can be swung around is fixed to the left end.
Due to the 5G's own weight, the left end part hangs down and can be tilted when no regulatory force is applied.

A pin 315H is provided in the middle of the separating lever 315A.
And is movable along the wall surface of the D-shaped cam groove portion 315J formed in the substrate 315B. Reference numeral 315K is a circular leaf spring attached to the substrate 315B, which is slidably contacted with the upper surface of the separating lever 315A to form a separating lever 315A.
Will be the guide surface for horizontal movement.

FIG. 9 shows a push-up means 314 for pushing up the tip of the separating lever 315A when necessary, and FIG.
Is a front view and FIG. 9B is a side view.

A solenoid SL4 is fixed to the lower portion of the base plate 314B of the separating lever pushing-up means 314, and a swing lever 314 is provided at one end of a plunger SL4A of the solenoid SL4.
One end of C is pin-connected. The swing lever 314C can swing about a fulcrum shaft 314D planted on the upper portion of the substrate 314B, and is biased in one direction by a torsion spring 315E. The base of a long rod-shaped push-up lever 314A is driven into the other end of the rocking lever 314C so that the tip thereof projects. The push-up lever 314A is the separation lever 3
It contacts the lower surface near the tip of 15A and holds it so that it can move up and down.

FIG. 7A shows an initial unloaded state in which the document stack is not placed on the feeding belt 311 of the document placing section 310. In this state, the separating lever 315A has a weight 315G.
Is tilted by its own weight and the right end portion is in a raised posture (first position). And the pin 315H is the cam groove 3
It has reached the top dead center of 15J in the figure and is stopped due to position restriction.
At the raised position of the separating lever 315A, the copy number separating sensor S14 is turned off.

FIG. 7B shows the feeding belt 3 of the document placing section 310.
11 shows a state in which the document bundle D is stacked on the document stack 11 and the leading end of the separating lever 315A is lowered by the weight of the document bundle D.
The pin 315H of the separating lever 315A descends along the path a of the cam groove portion 315J, passes through the cutout portion 311D of the feeding belt 311, and comes into contact with the lower push-up lever 314A to stop (the first stop). Position 3). In this descending state of the separating lever 315A, the copy number separating sensor S14 is turned on. At this time, the front end of the paper pressing lever 310Z presses the upper surface of the document stack by its own weight.

FIG. 7C is a side view showing the moving process of the separating lever 315A. As the bundle of originals on the original placing table 310 is fed out and conveyed back to the bottom, the front end of the separator lever 315A is sandwiched between the last page of the original placed bundle and the first page of the returned originals, so that the originals are returned. When the first page of the returned original reaches the uppermost position as shown in FIG.
In the state of (A), it jumps up into the upper space. At this time, the copy number sensor S14 is turned off.

FIG. 8D shows a state in which the separating lever 315A is retracted to the left in the drawing by the suction operation of the solenoid SL3 (second position). When a voltage is applied to the solenoid SL3, the plunger SL3A is attracted and the swing lever 315C is swung counterclockwise about the fulcrum shaft 315D, and the separator lever 315A joined by a pin 315F.
To the left. The pin 315H planted in the separating lever 315A moves diagonally downward along the path c of the cam groove portion 315J, comes into contact with the left end of the cam groove portion 315J, and stops moving. At this time, the leaf spring 315K slides on the upper surface of the separating lever 315A to prevent the separating lever 315A from jumping upward.

When the energization of the solenoid SL3 is turned off after a predetermined time, the swing lever 315c is supported by the spring 315E at the fulcrum 31.
Rotate clockwise around 5D to move lever 315A to the right. At this time, since the leaf spring 315K keeps the lever 315A in the horizontal direction, the pin 315H moves to the right in the path b, the tip of the cutout portion 311D of the sheet feeding belt 311 enters, and the pin 315H rotates upward by its own weight. Contact the lower surface of the document.

FIG. 8 (E) is a side view showing a state in which the separating lever 315A is raised by a predetermined amount by the push-up lever 314A. A notch 311D is formed at one end of the feeding belt 311 so that the separating lever 315A can be retracted below the feeding belt 311. When the document bundle is stacked on the feeding belt 311 and rotated, the cutout portion 311D may collide with the lower layer of the document bundle to cause conveyance failure. In order to prevent this, before the cutout portion 311D passes upstream of the document stack in the document transport direction, one end of the document stack is pushed upward so as not to interfere with the feeding belt 311. In other words, when the first document after the exposure processing is ejected and returned to the bottom of the document stack on the feeding belt 311 of the document placing section 310, the nipping piece portion 311 of the feeding belt 311 is rotated.
The separating lever is always positioned above the notch portion 311D preceding B, and the separating lever is surely placed in the feeding belt 31.
The separating lever 315A is raised by a predetermined amount so as to be above 1, and the relevant portion of the document stack is retracted upward. Therefore, the solenoid SL4 is actuated by the signal of the document exchange, the plunger SL4A is attracted, and the swing lever 314C is moved.
Is swung around the fulcrum shaft 314D to raise the lifting lever 314A. When the push-up lever 314A swings, the corresponding separation lever 315A is lifted upward by a predetermined amount and stopped. As a result, one end of the document stack of the separating lever 315A is lifted upward so that it can pass through the cutout portion 311D of the feeding belt 311.

As shown in FIGS. 2, 3, 5, and 6, the movable pressing plate 317 of the movable pressing means is integrated with the fixed bottom plate 310A on the downstream side of the feeding belt 311 in the document feeding direction. The drive plate 319 is screwed to the swing shaft 317A supported by the bearings provided on the both side plates, and can swing integrally. An elastically deformable member (for example, a torsion spring) 317B is wound around the swing shaft 317A, and both ends of the elastically deformable member 317B are pressed against the drive plate 319 and the movable pressing plate 317 to bias the spring. At this time, the movable pressing plate 317 and the drive plate 3
Although 19 is pushed in the opening direction of the torsion spring 317B, it is regulated so that the lower end of the movable pressing plate 317 contacts one end of the drive plate 319 and the opening angle between the two does not open beyond a certain amount. The spring pressure of the torsion spring 317B is adjusted to the set pressure.

An actuator portion (light shielding plate portion) 319A projects from one end of the swing shaft 317A. The actuator portion 319A includes a pressing home position sensor (for example, a photo interrupter) S3 fixed to the fixed bottom plate 310A.
The optical position of the drive plate 319 is turned on and off, and the home position of the drive plate 319 is detected. It can swing around the swing shaft 317A. Further, the gear G1 is attached to one shaft end of the swing shaft 317A.
Is fixed, and the gear G is fixed to the drive shaft of the pressing motor M1.
2 (see FIG. 6).

A document end stopper 318 is fixed to the main body of the automatic document feeder near the leading end of the movable pressing plate 317 on the downstream side of the document feeding.

Above the movable pressing plate 317, a feeding section 320 is provided.
Is provided. The feeding unit 320 includes a feeding roller 321.
A driving roller 323, a driven roller 322, a feed belt 324 that winds and rotates both rollers, and a double feed preventing reverse roller 325 located below the feed belt 324. The driving force of the driving motor M2 is transmitted to the driving roller 322 via the electromagnetic clutch CL1.

Frame body 321 holding the delivery roller 321
A is swingable around a support shaft A. The frame 321A
The actuator part 321 protruding at the tip of the
B is integrally formed and turns on / off the detection optical path of the pressure detection sensor S4 fixed at a predetermined position of the fixed stay member 300A of the automatic document feeder 300.

FIG. 10 is a schematic diagram showing a conveyance state of the document D discharged from the sheet discharge reversing section 350 to the feeding belt 311 of the document placing section 310 and the movable pressing plate 317.

After being detected by the leading edge passage sensor S9 of the document D1, the clutch is engaged, and when the leading edge of the document D is clamped by the clamping piece 311B of the feeding belt 311 which starts rotating from the home position, It is nipped on the rough surface of the rotating feeding belt 311, inserted into the lowermost layer of the stacked unprocessed original document D, and conveyed to the left in the figure (FIG. 10 (A),
(See (B)). As described above, at this time, the separating lever 315
A is a lifting lever 314A via a solenoid SL4
Then, it is lifted up through the cutout portion 311D of the paper feed belt 311 to raise the document stack by a predetermined amount.

At this time, the movable pressing plate 317 is in the lowered position, and the leading end of the document stack D is separated from the feed roller 321. The surface linear velocity of the feeding belt 311 is set to be slightly higher or constant than the surface linear velocity of the circulation paper discharge roller (deviation correction roller) 355 of the paper discharge reversing unit 350. Further, since the surface of the feeding belt 311 that comes into contact with the document D is a rough surface, the document D is reliably held by the feeding belt 311 and fed.

Further, since the surface of the feeding belt 311 which contacts the lowermost layer of the document bundle D is a smooth surface, the feeding belt 311 smoothly rotates in sliding contact with the lower surface of the document bundle.

Document D held on the feeding belt 311
Is slid on the upper surface of the movable pressing plate 317 slightly below the upper surface of the feeding belt 311 as the feeding belt 311 is turned downward along the driven roller 312B, and hits the document leading edge stopper 318. , Feeding stops. Therefore, if the entire circumference of the feeding belt 311 is set to be equal to or greater than the maximum length of the document D being circulated and conveyed in the feeding direction, the document returning operation is good.

Referring again to FIG. 2, an intermediate conveyance section 330 is provided on the downstream side of the original conveyance with respect to the feeding section 320. The intermediate conveying section 330 includes a first intermediate conveying roller pair 3 which is driven to rotate forward.
31, a curved guide plate 332, a pair of second intermediate conveying rollers 333 that are driven to rotate forward and backward, and a pair of third intermediate conveying rollers 334, and the document D sent from the feeding unit 320 is placed on one end of the platen glass 111. It forms a transportation route for transportation.

A reversing means is provided to the left of the third intermediate conveying roller pair 334 and to the left of the platen glass 111 in the drawing. The pair of reverse conveyance rollers 335 is always driven to rotate normally by the one-way clutch CL5. A curved guide plate 336 connects the nip positions of the third intermediate conveyance roller pair 334 and the reverse conveyance roller pair 335, and forms a document reverse feed path. A reversal detection sensor is provided in a part of the reversal feed path, and detects passage of a reversal fed document. 337 is a switching claw.

On the surface of the platen glass 111, a conveyor belt 341 is rotatably stretched between a driving roller 342, a driven roller 343, four document pressing rollers 344 and a tension roller 345. A clutch and a brake are rotatably supported on the shaft of the drive roller 342.
Is operated by the driving force of the drive motor M2.

The paper output reversing section 350 includes the paper output rollers 351, 352,
Switching claws 353, 357, reversing conveyance roller 354, circulation discharge roller 3
55 and guide plates 356A, 356B, 356C and the like. The paper discharge rollers 351, 352, the reverse paper discharge roller 354, and the circulation paper discharge roller 355 are driven by the paper discharge motor M3. The paper discharge roller 352 and the circulation paper discharge roller 355 are driven to rotate in the forward direction by a paper discharge motor M3, and the reverse conveyance rollers 351 and 3 are provided.
54 is driven in forward and reverse rotation. The switching claw 353 is driven by the switching solenoid SL1. The switching claw 357 is passively driven by the switching solenoid SL2.

On the upper part of the copying machine main body 100, a discharge tray section 360 is fixedly provided near the discharge opening of the discharge reversing section 350 of the automatic document feeder 300. The paper output tray unit 360 is
A fixed tray 361 having an inclined surface fixed to the upper surface of the casing of the copying machine main body 100 by a screw or the like, and a movable tray (resin tray that is swingable by being pivotally supported by a fulcrum shaft 362 provided at one end of the fixed tray 361. ) And 363. In the folded state of the movable tray 363, a reverse discharge path 364 is formed between the inclined upper surface of the fixed tray 361 and the inclined lower surface of the movable tray 363 with a constant space. The document D fed from the reversing and discharging roller 354 goes up the reversing and discharging path 364 and is temporarily stopped.
When the single-sided original is introduced into the automatic document feeder 300 by the reverse rotation drive of 54, and is in the ADF mode of a single-sided original, it is discharged to the outside of the machine by the discharge roller 352 of the discharge reversal unit 350 through the guide 356c and the movable tray 363. Placed on the top surface.

When the movable tray 363 of the paper discharge tray section 360 is swung and unfolded, the upper surface side of the fixed tray 361 is
By extending to the upper surface side of the movable tray 363, it is possible to eject and place a large original such as A2 size paper or fanfold paper (CFF).

In addition, the reverse circulation mode (R-R
At the time of (DH), the switching claw 357 is switched downward, and the document D conveyed to the reversal paper ejection path 364 is placed on the document through the reversal paper ejection roller 354, the guide plates 356C and 356B, and the circulation paper ejection roller 355. Returned to part 310.

FIG. 11 is a schematic diagram showing the document transport path (dotted line) in the RDH mode and the R-RDH mode.

FIG. 11 (A) is a schematic diagram of the RDH mode showing the circulation of originals during single-sided copying and single-sided copying. The one-sided original D is passed through the sequential circulation paths a, b, c, d, and e, and after the exposure processing, is passed through the paths f, g, and n of the sheet discharge reversing unit 350, and the feeding belt 311 of the original placing unit 310 is clamped. The sheet enters the one-sided portion 311B, is conveyed by the feeding belt 311, and is returned to the bottom layer of the original stack.

FIG. 11 (B) is a schematic view of the R-RDH mode showing the circulation and conveyance of the document at the time of double-sided document and double-sided copy. The path to the exposure process for the odd-numbered side of a two-sided original is
Same as the mode, one side copied sheets are stacked in ADU 180. Further, the original is sent again through the feeding paths a, b, c, d, the surface is inverted by i, and the original D after the exposure processing reaches the exposures f, j, k, and the surface when it is sent back by switching back is set. The original is returned to the original placing section 310 via the paths m and n.

FIG. 12 is a block diagram showing the drive system (power transmission system) of the automatic document feeder 300. The CPU controls all of the operations of feeding, feeding, and discharging the document circulation, document reversal circulation. Be done.

Of the various document transport operations in various modes,
As an example, the single-sided document circulation transport mode (RDH mode) will be described.

(1) Initialization (1A) Turn on the main switch of the copying machine main body 100. When the main switch is turned on, the pressing motor M1 starts to rotate in the reverse direction and the offset correction motor M4 starts to rotate in the normal direction. At the same time, the paper discharge motor M3 and the bottom return clutch CL4 are turned on to start the driving rotation of the driving roller 312A.

(1B) Movable pressure plate home position stop When the main switch is turned on, the pressure motor (stepping motor) M1 is driven to rotate in the reverse direction to swing the drive plate 319 and the actuator portion 319A fixed to the swing shaft 317A. When the pressing home position sensor S3 is turned on, the reverse rotation of the pressing motor M1 is stopped by the detection signal,
The drive plate 319 and the movable pressing plate 317 are stopped at the lowest initial position (home position). This is effective in absorbing the time lag of the drive gear and the sensor on. At this home position stop position, a clearance capable of accommodating a predetermined maximum amount of the document bundle D is maintained.

(1C) Placement of Document Bundle When the document stack D is placed on the feeding belt 311 and the movable pressing plate 317, the set detection sensor S1 is turned on and the ADF mode is set. At the same time, the size detection sensor S2 is turned on to detect the document size. Next, the R-RDH mode is selected and input.

(1D) Home Position Search Operation of the Offset Correcting Roller The offset correcting roller 355 is movable in the direction orthogonal to the sheet conveyance, and is driven by the offset correcting motor M4 which is driven and rotated by turning on the main switch. . An offset home position sensor S15 for detecting the roller position is provided outside the sheet passage of the offset correction roller 355.

When the main switch is turned on, the sensor S
If 15 is off, rotate the offset correction motor M4,
When the sensor S15 is turned on by moving the roller 355 in the depth direction, the motor M4 is stopped. The motor M4 is a step motor, and after stopping, a constant voltage is applied to bring it into a hold state. If the sensor S15 is on, the motor M4
Reversely, the roller 355 is moved in the front direction to turn off the sensor S15 once, and then the motor M4 is again rotated forward to stop and hold the motor M4 when the sensor S15 is turned on. By this operation, the motor M4 to the roller 355
The roller 355 always stops at an accurate predetermined position regardless of rattling of gears and the like. This predetermined position is usually adjusted to be substantially at the center of the possible range of the roller 355.

(1E) Bottom-Returning Feeding Belt Home Position Search Operation The bottom-returning feeding belt 311 having a nipping piece portion 311B partially hung between the driving roller 312 and the driven roller 313 has the bottom-returning feeding belt 311 shown in FIGS. Through hole for home position detection as shown in
311C is open. When the main switch is turned on, the paper discharge motor M3 and the bottom return CL4 are turned on, and the drive roller 31
Rotate 2 The drive roller 312 is a one-way rotating clutch C.
It is driven via L6 and always rotates in the direction of the solid line arrow regardless of the forward / reverse rotation of the motor M4.

When the home position detecting hole 311C on the feeding belt 311 passes through the belt home position sensor S13, the sensor S13 is turned off, and after a predetermined time, the bottom return clutch CL4 is turned off and, at the same time, the paper discharge brake BRK2 is turned on. Then, the drive roller 312A is suddenly stopped. As shown in the figure, the bottom return feeding belt 311 has the sandwiching piece portion 311B on the extension of the offset correction roller pair 355, and the cutout portion 311D is aligned with the position of the separating lever 315A.

(2) Circulation of Original Document By the above initialization operation, the preparation for feeding the original document is completed, and the document feeding is subsequently started. FIG. 13 is a schematic view showing a process of conveying originals of odd pages.

(2A) When the copy button is turned on, the pressing motor M1, the paper discharge motor M3, the bottom return clutch CL4
Is turned on, and ADF and copy can be started.

(2B) When the copy button is turned on, the bottom return clutch CL4 is turned on to start the low speed drive rotation of the paper discharge motor M3. As a result, the driving roller 312A is rotated and the feeding belt 311 is rotated. When the detection hole 311C of the feeding belt 311 passes through the belt home position sensor S13, the detection signal causes a feeding belt after a predetermined time.
311 is stopped by the brake BRK2, and then the copy number separating solenoid SL3 is turned on, and the separating lever 315A comes into contact with the lowermost layer of the document stack through the cutout portion 311D.

(2C) When the copy button is turned on, the pressing motor (stepping motor) M1 is driven and rotated, and the swing shaft is moved.
The movable pressing plate 317 oscillates and rotates via the drive plate 319 fixed to 317A and the torsion spring 317B, and the leading end of the movable pressing plate 317 rises to lift the stacked document stack D. In the ascending process, the swing angle of the swing shaft 317A counts the pulse count C1 by a rotary encoder or the like.

(2D) When the upper surface of the document stack D stacked on the movable pressing plate 317 is lightly pressed against the outer peripheral surface of the feed roller 321 which is lowered to a predetermined position by its own weight, the movable pressing plate 317 is moved. Feeding roller 321 with the stack of originals sandwiched
Raise. After rising by a predetermined amount, the pressure detection sensor S at the tip
4 is turned on, and counting is started. When it further oscillates, the frame body 321 holding the feed roller 321 comes into contact with a fixing member (not shown) and stops. However, drive plate 319
Is further driven and rotated to rotate counterclockwise while compressing the torsion spring 317B, so that the movable pressing plate 317 and the driving plate 319 are rotated.
The intervals between are getting narrower. When the pressure detection sensor S4 is turned on, the initial set pressure (for example, the roller own weight of 50 g) is reached, and counting of the count C1 is stopped.

(2E) The paper bundle thickness of the document bundle D is detected by the output of the count C1, and the press is predetermined by the document size detected by the size sensor S2 previously detected or the setting input of thick paper or thin paper. The designated pulse is determined by the pulse table.

The original sheet bundle thickness is detected from the count value of the count C1 and the sheet bundle thickness is set to be divided into, for example, three stages of multi, medium and clear.

As the original paper size, for example, B5 to
A3 size is set, and this is detected by the size detection sensor S2. When a stack of document sheets of a plurality of document sizes is mixedly mounted, the user specifies it by pressing a mixed mounting key mounted on the operation panel of the copying machine main body.
The paper thickness of one original paper is designated by pressing a thin paper key or a thick paper key placed on the operation panel.

As described above, the original sheet bundle thickness and the original size are automatically detected by the respective sensors, and the mixed originals and the sheet thickness are manually set.

The pressure pulse table is set in advance by these detected values and manual setting, and is stored in the non-volatile memory, and the count C2 is determined by these sheet condition inputting means.

(2F) When the count C2 is input by the designated pulse and the drive plate 319 is driven to continue counting the count C2, and the drive plate 319 is swung until the designated count number C2 counts up, The winding amount of the torsion spring 317B increases, the elastic force changes almost linearly, and the pressing force increases.

(1A27) When the count C2 is counted up, the movable pressing plate 317 has a predetermined pressing force (for example, 100 g).
Then, the document D is pressed against the feed roller 321 and the pressing motor M1 stops driving.

(2G) At the same time as the driving of the pressing motor M1 is stopped by the above count-up, the delivery clutch CL1
The drive motor M2 is turned on, the drive motor M2 is rotated at a low speed, and the document feeding is started. That is, the feed belt started to rotate by the driving force of the drive motor M2 rotated at a low speed.
The original document in the upper layer is sent out by 324, and only the uppermost original document D1 among the plurality of original documents sent out by the reverse roller 325 is separated and sent.

(2H) The front end of one sheet of the document D1 separated and fed is detected by the curl correction sensor S5, and a predetermined time (timer T
1) After the lapse of time, the drive motor M2 is turned off, the registration clutch CL2 is turned off and hits the stopped first intermediate conveyance roller (registration roller) 331 to form an accumulation, and the feed bend of the document D1 is corrected. (Figure 13 (A)
(2I) Before the timer T1 finishes timing, the timer T
2 by the discharge motor M3 and the discharge brake BRK2
Is turned off, the drive roller 312A suddenly stops its rotation, and the home position position of the sandwiching piece 311B of the feeding belt 311 is set.

(2J) Further, after a lapse of a predetermined time from the start of detection of the detection hole 311C of the feeding belt 311 by the timer T3, the drive motor M2 is re-driven and rotated. At this time, the drive motor M2 is rotated at a high speed, the registration clutch CL2 and the transport clutch CL3 are turned on simultaneously with the delivery clutch CL1, and the document D1 is transported downstream. When the leading edge of the document D1 crosses the passage detection sensor S6, the feed clutch CL1 driving the drive roller 323 is turned off, and the feed belt 324 is driven to rotate until the trailing edge of the document D1 passes through the sensor S6. After that, the document D1 is conveyed by the drive motor M1 by the first intermediate conveyance roller pair 331.

(2K) Further, when the timer T3 turns on the time counting path 3, the pressing motor M1 is switched to the reverse rotation, and the driving plate 319 and the movable pressing plate 317 are lowered to release the pressing and the driving plate 319. Has returned to the initial position,
When the home position detection sensor S3 detects it, the pressing motor M1 is stopped. Alternatively, when a plurality of originals are continuously fed, the driving plate 319 and the movable pressing plate 317 are not returned to the home position, and the pressing detection sensor S4 is used.
Based on the detection signal of 1) or the drive start signal in the separating direction of the drive means, the descent drive of the drive plate 319 and the movable pressing plate 317 is stopped in the middle.

(2L) After the sensor S13 detects the passage of the home position detecting hole 311C on the feeding belt 311, and after a predetermined time by the timer T3, the member separating solenoid SL3 of the pushing-up means 314 is turned off, and the pushing-up lever is pushed. 314A
Is descended. As a result, the separator lever 315A held on the push-up lever 314A also follows its own weight downward to release the push-up of one end of the document stack and retract to the bottom of the document in the lowermost layer. The stop position is detected by S14.

Here, if the original stack is first placed on the original placing section 31.
When the separator lever 315A is placed below the separator lever 315A of 0 or the separator lever 315A is inserted between the document stacks, the copy separator sensor S14 does not detect the stop position, and the signal causes the separator lever 315A located above to turn off the solenoid SL3. When the lift lever 314A is lowered and the solenoid SL4 is turned on, the separation lever 315A is moved to the position shown in FIG.
8C, the vehicle slides down along the path C shown in FIG. 8A and moves backward to the position shown in FIG. 8C. Then, the solenoid SL4 is turned off to urge the spring 315E to move the separating lever 315A forward. It reaches the position shown in B) and is inserted below the cutout 311D of the feeding belt 311 below the document stack.

(2M) Next, when the leading edge of the document D1 passes the registration sensor S7 and the signal is turned on, the conveyor belt 34
Counting is started by the encoder sensor S16 for the encoder plate RE directly connected to the first driving roller 342 and the third intermediate conveying roller pair (registration roller) 334. After the predetermined count (φ1) by the encoder RE, the drive motor M2 is turned off. Further, at this time, the encoder plate RE starts counting, and after a predetermined count (φ2), the registration clutch C
L2 and the transport clutch CL3 are turned off, and the transport brake BR
K1 is turned on, and the rotation of the conveyor belt 341 and the third intermediate conveyor roller pair 334 is stopped. At this time, the leading edge of the document D1 reaches a predetermined standby position (a position at a distance L1 from the stop position, for example, 236 mm) of the platen glass 111 and stops. (See FIG. 12 (B)) When the leading edge of the first original D1 passes the registration sensor S7 and the detection signal is turned on,
Based on this detection signal, the pressing motor M1 starts pressing driving of the driving means, and the driving plate 319 and the movable pressing plate 3 are started.
Then, 17 is raised and the pressing of the succeeding original document D2 is subsequently started.

(2N) After a predetermined time from the count-up (φ2) of the encoder plate RE, the drive motor M2 and the delivery clutch CL1 are turned on, and the delivery roller 321
Then, the feed belt 324 rotates at a low speed to feed the original D2 at a low speed, hit the first intermediate conveyance roller pair (registration roller) 331 to form an accumulation and stop the same as the original D1. (See FIG. 12 (C)) (2O) Next, after a predetermined time, the drive motor M2, the delivery CL1, the registration clutch CL2, and the transport clutch CL4.
On, the transport brake BRK1 is turned off, and the document D
1 and D2 are conveyed at high speed, and the original D1 is placed on the platen glass 111.
When the upper predetermined exposure position is reached, the drive motor M2 is turned off, and the transport clutch CL3 and the registration clutch CL
2 OFF and the conveyance brake BRK1 are turned ON to stop the document D1 at the exposure position, and at the same time, document D2 is placed on the platen glass.
Stop at the designated standby position at 111. (See FIG. 13D.) That is, in the present embodiment, the moving amount of the document D is managed by the pulse number count of the rotary encoder RE with the registration sensor S7 as a reference, without using the document stopper, and the reading position is read. Is to be carried to.

(2P) When both originals D1 and D2 are stopped,
Scanning exposure of the original D1 is performed by a signal from the main body of the copying machine. That is, the original D1 is exposed on the first surface by the exposure lamp of the scanning exposure unit 110 while the original D1 is stopped on the platen glass 111, and the original image is formed on the photosensitive drum via the lens, the mirror, and the like. Is formed. Then, a series of copying processes for the document D1 are performed.

During the exposure operation, the drive motor M2 and the clutch CL1 are actuated by the count-up of the timer, the feed belt 324 starts to rotate, the next original D3 is sent out, and the registration operation is controlled by the timer. Then, the document D3 is stopped at a position where the front end of the document D3 maintains a predetermined distance L1 from the trailing end of the document D2.

Therefore, at this time, the three originals D1 to D3 are arranged in a row at a predetermined interval L from each other on the conveying path from the separating and feeding means to the reading section. still,
At this time, the original document D1 is placed at the reading position of the platen glass 21, and the original document D2 stands by at a position that is stretched between the transport belt 141 and the second intermediate transport roller pair 132 (second transport roller pair). The original document D3 is waited at the position where it hits the registration roller 331, and the original documents D2 and D3 are waited in a state where the subsequent conveyance can be performed stably.

(2Q) Original Exchange After the exposure operation of the original D1 is completed, the drive belt M1 is rotated at a high speed to rotate the conveyor belt 141, and the paper discharge motor M3 is rotated at a high speed. The exposed original document D1 passes through the paper discharge reversing unit 350 and is returned to the original document placing unit 310.

(2R) Due to the high speed rotation of the paper discharge motor M3, the document D1 has already passed through the reverse paper discharge passage 364 of the paper discharge tray 360 through the reverse paper discharge roller 354 and the guide plate 356C and has already passed through the RDH.
The switching claw 357 swings by the switching solenoid SL2, and the guide plate 356 is passed through the branch portion where the upper passage is switched and opened.
Proceed in B. When the leading edge of the document D1 is detected by the paper discharge sensor S9 during this conveyance, the timer starts counting. When the timer counts up, the bottom return clutch CL4 is turned on. At this time, if the deviation detection sensor S10 is off, the deviation correction motor M4 is started to rotate in the depth direction. If the sensor S10 is turned on, the sensor S10 is moved to the front side, turned off, and then turned inward again to be stopped at the same time as the sensor is turned on, and the original is abutted against the width stopper plate 316 to correct the deviation and align. . The timer is set to turn on the bottom return clutch CL4 so that the front end of the document D1 is pinched by the pinching piece portion 311B of the feeding belt 311.

In the present embodiment, the conveyance distance from the paper discharge roller 351 to the sandwiching piece portion 311B has an interval equal to or larger than the paper passing size, but the rear end of the document D1 is discharged by a timer independent of the timer. After passing through the paper roller 351, the deviation correction motor M4 may be turned on so that the distance from the sandwiching piece 311B to the paper discharge roller 351 is maintained shorter than the original size.

(2S) Further, the bottom return feeding belt 311
Then, the offset correction roller pair 355 is rotated, and the document D1 is inserted below the upper document stack. Here, the separating lever 315A of the copy number separating means 315 is raised upward by a certain amount by the copy number separating solenoid SL4, and the sandwiching piece portion is provided.
The document D1 whose front end is nipped at 311B is inserted below the final undocumented document.

(2T) The document D4 is further sent out after the document replacement operation is completed, and the movable pressing plate 317 is lowered immediately after the registration is completed. It passes over the plate 317 and strikes against the document leading edge stopper 318 and stops.

(2U) When the document D4 is sent to the registration position, the rear end of the document D4 passes through the separating lever 315A,
The separating lever 315A moves upward, the copy number separating sensor S14 is turned on, and it is detected that the last document of the first circulation is sent out.

(2V) After the document D4 is conveyed to the second stop position, the document D1 returned to the document placing section 310 is fed again while the document D3 is being exposed. Similarly, when D2, D3, and D4 are sent out and D4 returns, the copy number separating solenoid S
The L3 is operated to move the separating lever 315 to the lower side of the document D4.
Insert A. This operation is repeated a predetermined number of times.

In this embodiment, after the resist feeding is completed, the movable pressing plate 317 is configured to return when the movable pressing plate 317 is lowered, but the feeding operation may be performed after the returning is completed. here,
A paper pressing lever 319 provided on the upstream side of the separating lever 315A in the conveying direction serves to surely insert the returning original document under the original document stack, and lightly presses the original document by its own weight.
The paper pressing lever 310Z is also effective for stabilizing the operation of the separating lever 315A when conveying curled paper or a small number of originals.

(3) R-RDH Mode (Double-sided Original Circulation and Transport Mode) The above operation is for single-sided copying of a single-sided original in the RDH mode. In the R-RDH mode in which a two-sided original is copied on both sides, the original is reversed in the first cycle, and only odd pages are copied (see FIG. 11A), and even pages are copied in the second cycle (FIG. 11 ( See B)). Of course, the copying machine body
100 side copy paper feeding operation is also in the above RDH mode, RR
The movement according to the DH mode will be performed.

FIG. 14 and FIG. 15 show a double-sided original copy R
FIG. 6 is a schematic diagram showing a document conveyance process in a −RDH mode. The document conveyance for even-page copying of a small size document will be described below.

(3a) FIG. 14A shows the starting state of the leading original D1 of even pages. At this time, the preceding document D4 is stopped at a predetermined position on the platen glass 111 and an exposure process is performed, and the leading end of the document D5 is at a standby position keeping a predetermined distance L1 from the document D4.

(3b) Next, the original D5 is a platen glass.
The film is conveyed to a predetermined position on 111 and exposed. At the same time, the leading original document D1 in the second cycle enters one end of the platen glass 111 and is stopped while maintaining the interval between the original documents D5 and L1. Further, during the D5 exposure operation, D2 is sent out and the registration is waited by the registration roller.

(3c) When the originals D5 and D1 are simultaneously conveyed and the trailing edge of the original D1 passes the registration sensor S7, the conveyor belt 341 is driven in reverse to feed D1 to the reversing path 336.

(3d) Subsequently, the document D1 is fed back, reversed through the path i, and enters the platen glass 111 with the second surface facing downward. The document D5 advances toward the document placing number 310. The reversal detection sensor S17 detects the leading edge of the document D1 and after a predetermined time M2 is turned off to switch to the normal rotation, but the reversing roller always rotates in the normal rotation.
Sent to the top. Further, at this time, after a lapse of a predetermined time from the sensor S17 being turned on, the delivery clutch CL1 is turned on to set D
2 is sent at a predetermined distance from D1.

(3e) The originals D1 and D2 are simultaneously conveyed,
The document D1 is stopped at a predetermined position on the right end of the platen glass 111 and is subjected to an exposure process. At this time, the document D2 advances to a predetermined standby position on the platen glass 111 and is stopped. D3 is sent during D2 exposure, and registration roller 331
Stop at the position where it hits.

(3f) The document D1 is discharged to the discharge reversal unit 350. At the same time, the document D2 enters the platen glass 111 surface.

(3g) The original D2 is turned upside down by the turning guide plate 336, and the platen glass is turned with the fourth side facing downward.
Enter one end of 111. During this time, the leading document D1 passes through the reversing paths j, k, m, and n in the discharge reversing unit 350 and advances to the document placing unit 310 with the first surface facing upward.

In the same manner, the even-numbered page document is turned upside down by the intermediate feeding unit 330, and is fed onto the platen glass 111 with the even-numbered page face down, and is turned upside down by the sheet discharge reversing unit 350 after the exposure processing. Then, the odd-numbered page surface is turned upward and returned to the lowermost layer of the document stack on the document placing section 310.

The feeding belt having the sandwiching piece and the movable pressing plate in the automatic document feeder of the present invention are effective when applied to a recycle type automatic document feeder (RDH). The present invention can be widely applied to a sheet re-feeding device in which the sending sheet setting unit and the discharged sheet placing unit are the same.

[0115]

As described above, according to the automatic document feeder of the present invention, the documents set or re-stacked on the document placing table are fed from the uppermost sheet of the document placing table to the sheet feeding section and the processing section. After that, since it is returned to the lowermost layer of the original stack on the original placing table again in a closed loop, the originals are not contaminated due to front and back friction between the originals. Further, the automatic document feeder of the present invention does not require suction work or the like and has a simple structure, so that it is not only effective in reducing the manufacturing cost, but also excellent in that noise and vibration are not generated. Have advantages.

Further, by using the wide belt having the sandwiching piece portion, it is effective to prevent the leading edge of the document from being damaged.

In particular, in the RDH mode or the R-RDH mode in the automatic document feeder of the present invention, when the double-sided document discharged from the paper discharge reversing unit is returned to the bottom, it is separated from the document on the document placing unit. Can be executed reliably and stably. Further, the copy number sorting means of the present invention allows easy manuscript operation without any trouble when the manuscript stack is placed on the manuscript placing part.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of a copying machine equipped with an automatic document feeder according to the present invention.

FIG. 2 is a sectional view of the automatic document feeder.

FIG. 3 is a perspective view of a main portion of a document placing portion.

FIG. 4 is a perspective view of a sheet feeding belt and related members of the document placing portion.

FIG. 5 is a front sectional view of a document placing section and a feeding section.

FIG. 6 is a plan view of a copy number dividing means and a pushing-up means.

FIG. 7 is a side view showing the operation of the copy number dividing means.

FIG. 8 is a side view showing the operation of the copy number dividing means.

9A and 9B are a front view and a side view of the lifting means.

FIG. 10 is a schematic diagram showing a document transportation path in a document circulation mode on a document placing section.

FIG. 11 is a schematic diagram showing a document transport path in an RDH mode and an R-RDH mode.

FIG. 12 is a configuration diagram showing a drive system of an automatic document feeder.

FIG. 13 is a schematic diagram showing an odd-numbered page original transport path in the R-RDH mode.

FIG. 14 is a schematic diagram showing the first half of the even-numbered-page original conveyance process in the above mode.

FIG. 15 is a schematic diagram showing the second half of the even-numbered-page original conveyance process in the above mode.

[Explanation of symbols]

 100 Copier main body 110 Scanning exposure section 111 Platen glass (reading section) 120 Image forming section 300 Recycling type automatic document feeder (RDH device) 310 Document placing section 310Z Paper pressing lever 311 Feed belt 311A Seam section 311B Nipple section (Gripper part) 311C Detection hole 311D Notch part 312A Drive roller 314 Separation lever pushing up means (pushing up means) 314A Pushing up lever 315 Separation means 315A Separation lever 316 Width stopper plate 317 Movable pressing plate 318 Original tip stopper 319 Drive Plate 320 Feeding Unit 321 Feeding Roller 324 Feed Belt 330 Intermediate Conveying Unit 331 Registration Roller (First Intermediate Conveying Roller Pair) 334 Registration Roller (Third Intermediate Conveying Roller Pair) 340 Conveying Unit 341 Conveying Belt 350 Paper Ejecting Reversing Unit 355 Circulation Paper ejection roller (deviation correction roller) 360 Paper ejection tray section a, b, c, d, e, i Paper feeding path f, g, h, j, k, m, n Ejection Paper path D, D1 to D5 Original (bundle of originals)

Claims (2)

[Claims] 1. A document placing portion capable of stacking a plurality of documents,
Paper feeding means for separating and feeding the originals one by one among the plurality of originals stacked on the original placing portion, and an image of the originals located downstream of the paper feeding means. A document including a conveying unit that conveys the document to the reading unit and a discharge unit that is located on the downstream side of the image reading unit in the document conveying direction and that returns the document discharged from the conveying unit to the lowermost layer of the document stacked on the document placing unit. In the circulating automatic document feeder of the upper feed bottom returning system, a separating unit for distinguishing and distinguishing the document fed from the document placing unit and the document returned from the discharging unit to the document placing unit, A first operation, which is provided in the vicinity of the end on the document side, in which the tip end of the separating lever of the separating means retracts from the first position above the end on the side of the stacked document to the second position outside the end on the document side, and the second operation. A second operation of moving the document from the position to the third position on the bottom of the document stack on the document placing section; Third act of biasing the raw Kotaba partially upward circulation type automatic document feeder being characterized in that is movable by. 2. A document placing portion capable of stacking a plurality of documents,
Paper feeding means for separating and feeding the originals one by one among the plurality of originals stacked on the original placing portion, and an image of the originals located downstream of the paper feeding means. A document including a conveying unit that conveys the document to the reading unit and a discharge unit that is located on the downstream side of the image reading unit in the document conveying direction and that returns the document discharged from the conveying unit to the lowermost layer of the document stacked on the document placing unit. In a circulating automatic document feeder of the upper feed bottom return type, a separating lever for distinguishing between a document fed from the document placing part and a document returned from the discharging means to the document placing part is provided. Delimiter means and push-up means for raising the tip of the delimiter lever are provided near the end portion on the document side,
A circulating automatic document feeder, characterized in that a drive force of a pushing-up means raises a document side end by a predetermined amount in the vicinity of a front end of a separating lever that has entered the bottom of a document stack on a document placing section.