JPH1010807A - Air feeding type recirculating document feeder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make the height of a placing plate lower than that in the case the placing plate is linearly inclined by bending the placing plate so as to make its inclined angle gentle as it goes to the upstream side in the moving direction of a document. SOLUTION: This device is constituted so that the document placed in a setting position in an initial stage is moved in the carrying direction P4 of the document, the document at the bottom is separated with air and after the separated document is carried, it is returned to the placing plate 210. The placing plate 210 is inclined to be lower as it goes to the upstream side in the carrying direction P4 of the document and bent from a first curve position 216 mid-way the placing plate 210, to make the inclined angle gentle.

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 Conventionally, a circulating document transporter which is applied to a copying machine or the like and 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 Docume)
nt 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. In order to set the original at the supply position, a moving unit for pushing the rear end of the original to transfer the original along a predetermined transport direction, and a moving unit for setting the original at the leading end of the original set at the supply position. Air separating means for blowing the air to separate the lowermost document, wherein the document placing plate is inclined so as to become lower toward the upstream side in the transport direction with respect to the horizontal plane, and has a predetermined bending position. And an air feed type circulating document feeder characterized by being bent so that the inclination angle becomes gentle.

In the present invention, air is blown to the leading end of a document set at the supply position. As a result, the original above the lowermost original rises. Here, the document placing plate is inclined so as to become lower toward the upstream side in the transport direction.
Accordingly, the upper document is shifted to the upstream side in the document transport direction, and the rear end portion is more likely to contact the moving unit. For this reason, even if air is blown to the leading end, it is difficult to disperse the original.

Further, since the original placing plate is bent so that the inclination angle becomes gentler from a predetermined bending position toward the upstream side in the transport direction, the original placing plate may be linearly inclined along the transport direction. , The height of the entire document placing plate is reduced. In particular, if the inclination angle of the document placing plate on the upstream side in the transport direction from the bending position is set to zero, the height of the document placing plate is further reduced. .

For example, when the moving unit can move only to the folding position in the transport direction, the length of the document mounting plate along the inclined direction from the folding position to the downstream side in the transport direction is equal to the length of the original. If the length is longer than the length along the transport direction, after the rear end portion exceeds the bending position, the original loses its support by the moving unit and fluctuates. Therefore, if the invention described in claim 3 is adopted, such a problem can be solved.

In other words, in the invention according to the third aspect, the length of the document placing plate along the inclined direction downstream from the bending position in the transport direction is smaller than the transport direction of the smallest size document among the mountable documents. 2. The length according to claim 1,
Alternatively, the circulating document feeder according to claim 2.

[0010]

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.

The RDH 100 is rotatably attached to the copier 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 generally described. 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 the end of copying. 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 original is to make the front side upward when returning the copied original 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 disposed near one edge of the mounting plate 210. A positioning plate 2 that can be manually slid along the rail 251 in the vertical direction of the document transport direction P4 along the rail 251 near the other edge of the mounting plate 210.
50 are arranged. Document transfer direction P of mounting plate 210
The mobile unit 300 is provided on the upstream side of 4.

When placing a document 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 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. 4A, the placing plate 210 is inclined so as to be lower as a whole with respect to the horizontal plane 215 in the document transport direction P4 on the upstream side. 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 is
It is necessary to set the angle to be necessary and sufficient to shift the original. 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, the mounting plate 210 is bent from the first bending position 216 in the original transport direction P4 so that the inclination angle becomes gentle, so that the mounting plate 210 is linearly formed. 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. In this embodiment,
Although the second mounting surface 218 is inclined at the inclination angle θ1, for example, as shown in FIG. 5, the second mounting surface 218 may be substantially parallel to the horizontal plane 215 by setting the inclination angle θ1 to zero. Good. According to this configuration, the height of the mounting plate 210 can be further reduced.

In this embodiment, when the mounting plate 210 is roughly classified, the first mounting surface 217 and the second mounting surface 218
Although it is bent in two stages, it may be bent in two or more stages. The moving unit 300 can move on the second mounting surface 218 along the direction of the arrow P1 to the first bending position 216 as shown by a two-dot chain line in FIG. 4B.
Conversely, the mobile unit 300 is located at the first bending position 2
16 cannot be moved downstream in the document transport direction P4. Therefore, the first bending position 216 and the reference position 213
The length r1 of the first placing surface 217 along the original transport direction P4 between the original transport direction P4 and the original transport direction P4
Is set to be equal to or less than the length r2. That is, r1
If> r2, the movement of the moving unit 300 stops before the document is completely set at the supply position 212, and it becomes impossible to support the rear end of the document. Therefore, the document is separated by the action of gravity. This is because there is a danger.

FIG. 6 is a block diagram showing an electrical configuration related to the original setting operation of the RDH 100. RDH1
00, the CPU 5 for the main body provided in the copier main body 50
The document setting operation is performed in response to the document transfer start signal given from the second document transfer operation. The RDH 100 includes an RDH CPU 101 functioning as a control center of the RDH 100. The RDH CPU 101 is connected to the size detection sensor 252, the document height sensor 312, and the memory 102.

The size detection sensor 252 includes the positioning plate 2
The size of the document placed on the placement plate 210 is detected based on the slide amount when the slide 50 is made to slide. The document height sensor 312 is connected to the moving unit 30.
0, which is included in the original pressing mechanism 310 provided in the original plate 0 and is displaced by the pressing bar 311 pressing the rear end side of the original.
The number of originals placed on the sheet 10 is detected.

The memory 102 stores a document size and a set air volume corresponding to the document amount. 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. 7 is a flowchart for explaining the document setting operation. A plurality of originals 201 are placed on the mounting plate 210
7 (a), when the print key 53 (see FIG. 6) is pressed, the blower fan 5
53 (see FIG. 2) is driven, and air is blown from the air outlet 552. In addition, the moving unit 300 has an arrow P1.
Move along the direction. 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, the pull-in belt 517
Rotates along the arrow P2 direction, and air is sucked into the suction fan 515 (see FIG. 2) via the suction duct 511. As a result, the lowermost original 202 of the originals 201 is pulled in while being attracted to the pull-in belt 517 (FIG. 7B).

Here, at the time of document setting, as described above, the peripheral speed v1 of the pull-in belt 571 is more
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 lowermost document 202 can be surely placed first (FIG. 7C).

When the document is conveyed to the vicinity of the reference position 213 in this state, the air blown from the blower port 552 is blown to the leading end of the document 201. At this time, since the original 201 has been transported with the lowermost original 202 at the top, air enters between the lowermost original 202 and the upper original 203. In addition, at this time, the amount of air blown out from the blowing port 552 is stable at a set airflow according to the document size and the document amount. As a result, the upper document 203 is reliably levitated (FIG. 7D).
). As a result, the lowermost document 202 is separated.

The mounting plate 210 is inclined so as to become lower toward the upstream side in the document transfer direction P4. In particular, the inclination angle θ1 (see FIG. 4A) of the first mounting surface 217 provided with the pull-in belt 517 is set to be larger than the inclination angle θ2 of the second mounting surface 218. Therefore, the upper document 203 raised by the air is moved in the document transport direction P4.
And the rear end thereof abuts on the moving unit 300. This prevents the upper document 203 from being separated.

The leading end of the original 201 is positioned at the reference position 2
13, the original 201 is moved to the supply position 212 (FIG. 3).
reference. ). Thus, the setting of the original is completed. Thus, the lowermost document 202
Are set in a separated state, so that only the document 202 is sent to the transport path 402. Then, from the bottom 2
The original at the stage 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. 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 case where the present invention is applied to the RDH 100 mounted on a copying machine is described as an example. However, the present invention is also suitable for an RDH mounted on another image forming apparatus such as a facsimile machine. Applicable to

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

[0043]

As described above, according to the present invention, the original placing plate is inclined so as to become lower toward the upstream side in the transport direction, so that the upper original is shifted to the upstream side in the original transport direction and its rear end is shifted. Can easily come into contact with the mobile unit. for that reason,
Even if air is blown to the leading end, the document is less likely to be scattered. Moreover, since the original placing plate is bent so that the inclination angle becomes gentle from a predetermined bending position, compared with the case where the original placing plate is inclined so as to decrease linearly toward the upstream side in the transport direction, The height of the entire document placing plate is reduced. for that reason,
The height of the entire apparatus can be suppressed, which can contribute to downsizing of the apparatus.

[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 diagram for explaining a configuration according to another embodiment of the mounting plate.

FIG. 6 is a block diagram showing an electrical configuration related to a document setting operation of the RDH.

FIG. 7 is a flowchart for explaining a document setting operation.

[Explanation of symbols]

 100 RDH 200 Document placement part 210 Placement plate 211 Initial setting position 212 Supply position 215 Horizontal plane 216 First bending position 217 First placement surface 218 Second placement surface θ1, θ2 Tilt angle P4 Document transfer direction

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 original in a predetermined transport direction, and an air separating means for blowing air to the leading end of the original set at the supply position to separate the lowermost original. The document placing plate is inclined so as to become lower toward the upstream side in the transport direction with respect to the horizontal plane, and is bent so that the inclination angle becomes gentle from a predetermined bending position. Characterized by an air-feed circulation type document feeder. 2. The air-feed type circulating document feeder according to claim 1, wherein the inclination angle of the document loading plate upstream from the bending position in the transport direction is zero. 3. The length of the original placing plate along the inclined direction downstream from the bending position in the transport direction is less than or equal to the length along the transport direction of the smallest original among the mountable originals. The air-feed type circulating document feeder according to claim 1 or 2, wherein: