JPH1010808A - Air feeding type recirculating document feeder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily separate a document at the bottom by setting the document, in a state where the document at the bottom is surely at the head, so as to facilitate the entering of air into the gap between the document at the bottom and the document thereon. SOLUTION: This device is constituted so that the documents set at a feeding position are separated one by one with the air and after the separated document is carried, it is returned to a placing plate 210. In such a case, when the document placed on the placing plate 210 is moved in the carrying direction P4 of the document, the circumferential speed of a pull-in belt 517 for pulling the document at the bottom in the carrying direction P4 of the document, while sucking the document at the bottom is faster than the moving speed of a moving unit 300 for pushing the rear end part of the document, to move it in the carrying direction P4 of the document.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air-feed type circulating document feeder applied to an image forming apparatus such as a copying machine.

[0002]

2. Description of the Related Art A circulating document which has been conventionally applied to a copying machine or the like, supplies a document set on a document placing portion to an image forming position, and returns the document after image formation to the document placing portion. RDH (Recycle Docu)
ment Handler) is known. When feeding documents one by one from a plurality of stacked documents, it is necessary to separate only the lowermost document from the upper document in order to prevent double feeding. There is a so-called air feed type using air (for example, see Japanese Patent Application Laid-Open No. 1-139440).

[0003] In the air feed type RDH, suction is performed from below a document set on a document placing portion,
Air is blown against the leading edge of the document. As a result, only the lowermost document is attracted to the feed belt, and at the same time, the upper document floats. As a result, only the lowermost document is separated from the upper document.

[0004]

However, the separation performance of the conventional air-feed type RDH is insufficient.
There is a possibility that a problem related to paper feeding such as double feeding or document jam may occur. Therefore, further improvement in separation performance has been desired. SUMMARY OF THE INVENTION It is an object of the present invention to provide an air-feed type circulating document feeder that can solve the above-mentioned technical problems and improve the separation performance.

[0005]

According to the first aspect of the present invention, there is provided an original placing plate on which an initial setting position and a supply position are respectively set, and an original placing plate which is placed at the initial setting position. A moving unit for pushing the rear end of the original to transfer the original along a predetermined transport direction in order to set the original at the supply position, and an air type provided in relation to the supply position. A suction belt, air separating means for blowing air to the leading end of the document set at the supply position to separate the lowermost document, and the air-type suction belt and air in response to a document transfer start signal. Means for moving the document from the initial setting position to the supply position by driving the separating means and moving the moving unit at a set speed lower than the air type suction belt. An air feed, recycle document feeder according to symptoms.

According to the present invention, when the document transfer is started, the document placed at the initial set position is transferred to the supply position by the moving unit, and the lowermost document in the document is attracted to the pneumatic pull-in belt. It is drawn while being done. At this time, the pneumatic retraction belt is driven to rotate faster than the movement of the moving unit. Therefore,
The document is set at the supply position with only the lowermost document pulled out. Therefore, air easily enters between the lowermost document and the document stacked thereon.
As a result, the lowermost document can be reliably separated.

According to a second aspect of the present invention, in the air-feed type circulating original transport apparatus according to the first aspect, the original placing plate is inclined so as to become lower toward the upstream side in the transport direction. is there. According to the present invention, since the document placing plate is inclined so as to become lower toward the upstream side in the document transfer direction, the upper document raised by the air can be easily shifted to the upstream side in the transfer direction. Therefore, the rear end of the document can be easily brought into contact with the moving unit.

According to a third aspect of the present invention, the document placing plate is bent so that the inclination angle becomes gentle from a predetermined bending position. This is an air-feed circulation type document feeder. According to the present invention, since the document is bent so that the inclination angle becomes gentle from the predetermined bending position, the height of the entire document placing plate can be reduced as compared with the case where the document mounting plate is inclined linearly along the transfer direction. Becomes lower.

[0009]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a cross-sectional view showing an internal configuration of an air-feed circulation type document feeder (hereinafter, simply referred to as “RDH”) to which an embodiment of the present invention is applied. The RDH 100 is mounted on the upper surface of the copying machine main body 50, and automatically supplies the original to the contact glass 51 provided on the upper surface of the copying machine main body 50, and returns the copied original to the original position. The original can be automatically re-supplied onto the contact glass 51.

[0010] The RDH 100 is rotatably attached to the copying machine main body 50. Specifically, it can be displaced between a state in which the upper part of the copying machine main body 50 is covered (a state shown in the figure) and a state in which it is released. The RDH 100 includes a document placement unit 200 for placing a document, a moving unit 300 for transferring and setting the placed document along the document transport direction P4, and a copying machine main body. A document supply unit 400 for supplying the document to the document supply unit 50; a document separation mechanism 500 for separating the set document to feed the documents one by one to the document supply unit 400;
The conveyance belt unit 600 for moving the original supplied to the zero side in the supply direction or the opposite supply direction, and the original discharge unit 70 for discharging the original from the copying machine main body 50 side.
0.

Next, the function of each part of the RDH 100 will be described generally. The document placing portion 200 has a placing plate 21 that is inclined so as to become lower toward the upstream side in the document transport direction P4.
0 is provided. For example, B5
Documents of up to A3 size can be placed. When a document is placed on the placing plate 210, the positioning plate 2 disposed opposite the reference plate 230 along the side edge of the document.
50 is manually moved in a direction perpendicular to the document transport direction P4. Thereby, the original is moved in the original transport direction P4.
Can be positioned with respect to

When the print key for instructing the start of copying is pressed in such a state, the pressing bar 3 provided in the original pressing mechanism 310 in the moving unit 300 is pressed.
After having retracted into the mobile unit 300 once, it rotates in the rotation direction P3 and stands up. Then, it protrudes out of the mobile unit 300 and then falls down. As a result, the rear end of the placed document is pressed. Thereafter, the moving unit 300 moves along the moving direction P1. As a result, the document can be positioned in the document transport direction P4. In this way, the setting of the original is completed in a state where the original is positioned in two directions, the original transport direction P4 and the vertical direction thereof.

Reference numeral 295 denotes a document presence / absence sensor for detecting the presence / absence of a document serving as a trigger for returning the moving unit 300 to the original solid line state after copying is completed. The document set on the document placement unit 200 is guided to the document supply unit 400, and is sent out along a sheet feeding path 402 by a pair of sheet feeding rollers 401. The original sent out to the paper feed path 402 is supplied to the conveyance belt unit 600 after the supply timing is adjusted by the registration roller pair 403.
Is placed on the contact glass 51 of the copying machine main body 50.

At this time, if the supplied original is a one-sided original, the copying operation by the copying machine main body 50 is executed as it is. On the other hand, if the supplied original is a two-sided original, the original is turned over before the copying machine 50 executes the copying operation. More specifically, the double-sided document placed on contact glass 51 is pulled back to reversing path 405 by transport belt unit 600. The returned document is reversed by passing through the reversing path 405 with the rotation of the conveyor belt unit 600, the pair of reversing rollers 404 and the pair of registration rollers 403, and the contact glass 51 is conveyed by the conveyor belt unit 600.
Placed again on top. Then, a copying operation is performed in this state. That is, the back side is first copied. Thereafter, the sheet is turned over again and placed on the contact glass 51 three times, and then a copying operation is performed to copy the front side.

The reason why the back side is copied first in the case of a double-sided document is to make the front side face up when returning the copied document to the original position. The document separation mechanism 500 separates a document using air before the document is guided to the document supply unit 400. The document separation mechanism 500 includes a document suction unit 510 for sucking air and sucking the lowermost document on the mounting plate 210, and a document floating unit for floating documents stacked on the sucked document by air. 550 and the sucked original is sent to the original supply unit 4.
And a document draw-in section 570 for drawing the document to the 00 side.

The original after the copying operation is completed is sent to the original discharge section 700 by the transport belt unit 600. The document sent to the document discharge unit 700 is drawn into a paper discharge path 702 by a pair of paper discharge rollers 701. After that, the original is discharged by a paper discharge path 70 by a paper discharge roller pair 703.
2, and is discharged to the original placing portion 200 by the pair of discharge rollers 704 and 705. At this time, when a document remains on the document placing portion 200,
The original is ejected thereon. That is, the original is returned to the original position. Thus, the document is circulated in the RDH 100.

The moving unit 300 includes a document discharging unit 700
To go back and forth. Paper discharge path 702
Is constituted by a gap formed between the document discharge unit 700 and the moving unit 300. Further, since the moving unit 300 moves back and forth with respect to the document discharge unit 700, the discharge roller pair 705 is provided on the moving unit 300 side, and moves with the movement of the moving unit 300. .

FIG. 2 is a simplified plan view showing the configuration centering on the mounting plate 210. A reference plate 230 is arranged near one edge of the mounting plate 210. A positioning plate 25 which can be manually slid along the rail 251 in the vertical direction of the document transfer direction P4 along the rail 251 so as to face the reference plate 230 near the other edge of the mounting plate 210.
0 is arranged. Document transport direction P4 of mounting plate 210
A moving unit 300 is provided on the upstream side of.

When placing an original on the placing plate 210,
It is placed at the initial setting position 211 as shown by oblique lines in FIG. Specifically, the right edge and the rear end of the document are placed along the reference plate 230 and the moving unit 300, respectively, and the positioning plate 250 is slid along the rail 251 to move the positioning plate 250 to the left side of the document. Align to the edge.

Returning to FIG. 2, the mobile unit 300 includes:
The driving force from the unit motor M1 is transmitted. When the driving force is transmitted from the unit motor M1, the moving unit 300 moves along the moving direction P1, as indicated by the two-dot chain line. As a result, the rear end of the document is pushed in the document transport direction P4. Thus, the document placed on the placing plate 210 can be transported along the document transport direction P4.

The transfer of the document is performed until the document is set at the supply position 212 as shown in FIG. Specifically, the process is performed until the leading end of the document is along the reference position 213 corresponding to the right end of the air duct 551. Returning to FIG. 2, downstream of the placing plate 210 in the document transfer direction P4, 6
Book pull-in belts 572,573,574,575,57
6,577 are arranged in parallel in a direction perpendicular to the document transport direction P4. Of these, the upper four pull-in belts 572 to 575 are wound around pairs of rollers 513 and 514 along the document transport direction P4. The two pull-in belts 576 and 577 on the lower side of the drawing are wound around a roller 513 and a roller (not shown).

The roller 513 is mounted on a roller shaft 516. The roller shaft 516 has a belt motor M2
Is transmitted. When the belt motor M2 is driven, the roller shaft 516 and the roller 51
3 rotates along the rotation direction P5. As a result, the pull-in belts 572 to 577 rotate in the rotation direction P2. Thus, the lowermost document among the documents on the pull-in belts 572 to 577 can be pulled in along the document transport direction P4.

The pull-in belts 572 to 577 have a plurality of through holes 578 formed therein. Retraction belt 572-57
7, a suction duct 5 is provided on the mounting plate 210 facing the lower surface of the suction duct 5.
The suction port 512 to which 11 was connected is formed. Suction duct 511 is connected to suction fan 515.
The suction fan 515 is driven by a suction fan motor M3.

The suction fan 515 is connected to the suction fan motor M3.
When driven by the air, the air is sucked into the suction port 512 through the through hole 578, and finally, the suction fan 515.
Sucked into. Thereby, the pull-in belts 572 to 57
7 can be attracted to the pull-in belts 572 to 577. An air duct 551 is disposed downstream of the mounting plate 210 in the document transport direction P4. A blower fan 553 is connected to the blower duct 551. The ventilation duct 551 has a plurality of ventilation ports 55.
2 (see FIG. 1) is formed so as to face the mounting plate 210 along the vertical direction of the document transport direction P4. The blower fan 553 is driven by a blower fan motor M4.

The blower fan 553 has a blower fan motor M4.
When driven, the air is supplied from the blower fan 553 to the blower duct 551, and the air is blown obliquely from the blower port 552 toward the mounting plate 210. FIG.
FIG. 4 is a simplified cross-sectional view for explaining the configuration of the mounting plate 210 more specifically. As shown in FIG. 4, the mounting plate 210 is inclined so as to be generally lower with respect to the horizontal plane 215 toward the upstream side in the document transport direction P4. This is because by utilizing gravity, the upper document raised by the air is shifted to the upstream side in the document transport direction P4 so that the rear end of the document can be easily brought into contact with the moving unit 300. Therefore, the inclination angle of the mounting plate 210 needs to be set to a necessary and sufficient angle to shift the upper document. However, if the mounting plate 210 is inclined linearly at this angle of inclination, a problem arises in that the height of the entire mounting plate 210 increases.

Therefore, in this embodiment, the mounting plate 210
Is inclined in two stages. More specifically, the mounting plate 2
Reference numeral 10 denotes a first mounting surface 2 on the downstream side in the document transport direction P4 from the first bending position 216 with the first bending position 216 as a boundary.
17 and the original folding direction P from the first bending position 216.
4 on the upstream side. First mounting surface 2
17 is further bent so that the downstream side in the document transport direction P4 from the second bending position 219 is parallel to the horizontal plane 215. Retraction belt 5 described with reference to FIG.
17, the reference plate 230 and the positioning plate 250 are all provided on the first mounting surface 217.

Each of the mounting surfaces 217 and 218 has a horizontal surface 215.
Are inclined at different inclination angles to each other. More specifically, the first placement surface 217 is inclined at an inclination angle θ1 with respect to the horizontal plane 215, and the second placement surface 218 is inclined at an inclination angle θ2 with respect to the horizontal plane 215. Tilt angle θ1
Is set smaller than the inclination angle θ2. For example, θ1 = 7 degrees and θ2 = 9 degrees.

As described above, since the placing plate 210 is bent from the first bending position 216 toward the document transfer direction P4 so that the inclination angle becomes gentle, the placing plate 210 is linearly bent. The height of the mounting plate 210 can be reduced as compared with the case of inclining. Therefore, the height of the entire RDH 100 can be reduced. FIG. 5 is a block diagram showing an electrical configuration related to the document setting operation of the RDH 100. In the RDH 100, a document setting operation is performed according to a document transfer start signal provided from a main body CPU 52 provided in the copying machine main body 50.

The RDH 100 includes an RDH CPU 101 functioning as a control center of the RDH 100. The RDH CPU 101 includes a size detection sensor 25.
2. The document height sensor 312 and the memory 102 are connected. The size detection sensor 252 is
The size of the document placed on the placement plate 210 is detected based on the amount of sliding when 0 is slid. The document height sensor 312 is connected to the moving unit 300.
The pressing plate 311 is included in the document pressing mechanism 310 provided therein, and is displaced by the pressing bar 311 pressing the rear end side of the document.
This is to detect the amount of the original placed at 0.

The memory 102 stores a document size and a set air volume corresponding to the document volume. The set air volume is
It corresponds to the amount of air blown out from the blower fan 553 and the amount of air sucked in by the suction fan 515, and is set to be larger as the document size is larger or the document amount is larger. Also, RD
The H CPU 101 is connected to the main CPU 52. The output of a print key 53 for instructing the start of copying is given to the main body CPU 52. When the print key 53 is pressed, the main body CPU 52 gives a document transfer start signal to the RDH CPU 101. The RDH CPU 101 executes a document setting process in response to the document transfer start signal.

More specifically, the RDH CPU 101
Drives a unit motor M1 and a belt motor M2 when a document transfer start signal is given. As a result, the moving unit 300 starts to move in the moving direction P1 (see FIG. 1), and the roller 513 moves in the rotational direction P4.
(See FIG. 2), and the pull-in belt 571 wound around the roller 513 starts rotating along the rotation direction P2 (see FIG. 1). At this time, CP for RDH
U <b> 101 controls the rotation speeds of the belt motor M <b> 2 and the unit motor M <b> 1 such that the peripheral speed v <b> 1 of the pull-in belt 571 is faster than the moving speed v <b> 2 of the moving unit 300.

The RDH CPU 101 refers to the outputs of the size detection sensor 252 and the document height sensor 312 to obtain the size and the amount of the document placed on the placing plate 210. Next, the set air volume is acquired by referring to the memory 102 based on the acquired document size and document amount. Further, the RDH CPU 101 sets the blower fan motor M4 and the suction fan motor M over the full drive time Δt after the print key 53 is pressed.
After fully driving the fan motor 3, the blower fan motor M4 and the suction fan motor M3 are driven in accordance with the obtained set air volume. As a result, the blower fan 553 and the suction fan 515 rotate according to the set airflow after full rotation. As a result, the air flow rate rises rapidly with the passage of time and then stabilizes at the set air flow rate.

As described above, the motors M4 and M3 are driven for a full drive time Δt after the print key 53 is pressed.
Is fully driven, the unstable state when the fan starts up can be quickly eliminated, and the air flow can be stabilized at the set air flow. FIG. 6 is a flowchart for explaining the document setting operation. A plurality of originals 201 are placed on the mounting plate 210
When the print key 52 (see FIG. 5) is pressed in the state of being placed on the air blower 5 (see FIG. 6A),
53 (see FIG. 2) rotates, and air is blown out from the blower port 552. The moving unit 300 moves in the moving direction P.
Move along 1 As a result, the document 201 is transported by the moving unit 300 with its rear end pushed in the document transport direction P4. Further, while the retracting belt 571 rotates in the rotational direction P2, the suction duct 5
Air is sucked into the suction fan 515 (see FIG. 2) through the air inlet 11. As a result, the lowermost document 202 is pulled in while being attracted to the pull-in belt 517 (FIG. 6B).
).

At the time of document setting, the peripheral speed v1 of the pull-in belt 571 is higher than that of the moving unit 3 as described above.
Since the document is controlled so as to be faster than the moving speed v2 of 00, the lowermost document 202 is drawn in the document transport direction P4 at a higher speed than the other documents 203 stacked thereon. . As a result, the top of the original 202 at the bottom can be reliably set as the top (FIG. 6C).

When the document 201 is conveyed to the vicinity of the reference position 213 in such a state, the air blown from the air blowing port 552 is blown to the leading end of the document 201. At this time, since the lowermost original 202 of the original 201 is at the top, the air enters between the lowermost original 202 and the upper original 203 very easily. In addition, at this time, the amount of air blown out from the blowing port 552 is
It is stable at the set airflow according to the document size and the document amount. As a result, the original document 203 in the upper stage is reliably levitated (FIG. 6D). As a result, only the lowermost document 202 is separated.

Further, since the placing plate 210 is inclined so as to become lower toward the upstream side in the document transfer direction P4, the upper document 203 raised by the air is shifted to the upstream side in the document transfer direction P4 and its rear end. The unit contacts the mobile unit 300. This prevents the upper document 203 from being separated. Thereafter, the leading end of the document 201 is moved to the reference position 21.
When the number reaches 3, the document 201 is set at the supply position 212 (see FIG. 3). Thus, the document setting is completed.

As described above, since the lowermost document 202 is set in a state where it is securely separated, only the document 202 is sent out to the transport path 402. Thereafter, the second original from the bottom is attracted to the pull-in belt 517. as a result,
Air blown out from the air blowing port 522 enters between the sucked document and the document stacked thereon. As a result, the lowermost document among the remaining documents can be separated.

By repeating such an operation,
A plurality of set originals can be separated one by one. As described above, according to this embodiment, the placing plate 210 is inclined so as to become lower toward the upstream side in the document transfer direction P4, and the peripheral speed v of the pull-in belt 571 at the time of document setting.
1 is set to be faster than the moving speed v2 of the moving unit 300, so that the lowermost document is surely placed at the top,
Further, the upper original can be set in a state shifted to the upstream side in the original transport direction P4.

As a result, air can be reliably introduced between the lowermost document and the document stacked thereon. Therefore, the document separating performance can be improved. For this reason, it is possible to reliably prevent the occurrence of a problem related to paper feeding such as double feeding or document jam. Therefore, a high-performance copying machine can be provided. Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments. For example, in the above embodiment, the present invention is applied to an RDH1 mounted on a copying machine.
Although the case where the present invention is applied to 00 is described as an example, the present invention can be suitably applied to an RDH mounted on another image forming apparatus such as a facsimile apparatus.

In addition, various design changes can be made within the scope described in the claims.

[0041]

As described above, according to the present invention, since the retracting belt is made to move faster than the moving speed of the moving unit, it is possible to set the original with the lowermost original securely placed first. Can be. Therefore, air can be reliably introduced between the lowermost document and the other documents above the lowermost document. Therefore, the document separation performance can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an internal configuration of an RDH to which an embodiment of the present invention is applied.

FIG. 2 is a plan view schematically showing a configuration centering on a mounting plate.

FIG. 3 is a diagram for explaining an initial setting position and a supply position.

FIG. 4 is a diagram for more specifically explaining the configuration of a mounting plate.

FIG. 5 is a block diagram showing an electrical configuration related to a document setting operation of the RDH.

FIG. 6 is a flowchart for explaining a document setting operation.

[Explanation of symbols]

 100 RDH 101 CPU for RDH 200 Document placement part 210 Placement plate 211 Initial setting position 212 Supply position 300 Moving unit 500 Document separation mechanism 510 Document suction part 550 Document floating part 570 Document drawing part 571-577 Retraction belt M1 Unit motor M2 belt motor

Claims (3)

[Claims] An original setting plate on which an initial setting position and a supply position are respectively set; and a rear end portion of the original placed in the initial setting position for setting the original on the supply position. A moving unit for pushing and transporting the document along a predetermined transport direction, an air-type suction belt provided in relation to the supply position, and blowing air to the leading end of the document set at the supply position. Air separating means for attaching and separating the lowermost document, in response to a document transfer start signal, driving the air suction belt and the air separating means, and moving the moving unit to a position higher than the air suction belt. Means for moving the document from the initial setting position to the supply position by moving the document at a slow set speed. 2. An air-feed type circulating document feeder according to claim 1, wherein said document placing plate is inclined so as to become lower with respect to a horizontal plane toward an upstream side in a transfer direction. 3. The air-feed type circulating original according to claim 2, wherein the original placing plate is bent so that the inclination angle becomes gentle from a predetermined bending position. Transport device.