JPS628375B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic paper feeder for feeding paper placed on a paper feed tray, for example, feeding a document to a transparent document tray in a copying machine or the like.

2. Description of the Related Art Recently, due to the increase in copying operations, automatic document feeders have been proposed and put into practice, which feed, for example, a sheet-shaped original onto an exposure surface and then feed the original on the exposed surface after copying is completed. In other words, in conventional copying machines, it is necessary to open the document cover that covers the exposure surface, set the document on the exposure surface, and then open the document cover again and remove the document after copying is complete. Therefore, when copying a large number of originals, the above-mentioned repetitive work is extremely troublesome and takes a long time, resulting in great waste. Therefore, the above-mentioned automatic document feeder has become desirable.

FIG. 1 is a sectional view showing an example of an automatic document feeder. In the figure, 1 is the main body of the copying machine, 2 is a document table made of a transparent body provided on the top of the main body of the copy machine, 3 is an automatic document feeder located opposite to the surface of the document table, 4
is a tray that receives a document sent out from the document table 2. The automatic document feeder 3 is comprised of a document feeder 5 that holds a document, and a transport mechanism 6 that feeds the document on the document feeder 5 to the exposure surface 2 and sends out the document on the exposure surface 2.

Further, a feed roller 7 is provided opposite to the paper feed port of the paper feed table 5, and the document on the table 5 is sent to the conveyance mechanism 6 by this roller 7.

In the above system, when inserting sheet originals one by one manually, if the sheet originals are inserted with the paper feed tray 5 indicated by the dotted line (horizontal position),
The document is sent to the document table 2 by the action of the feed roller 7.
In addition, when placing a large number of originals on the paper feed table 5 and feeding the originals one by one to the document table 2, the paper feed table 5
Tilt it as shown in the figure. As a result, the originals are always allowed to fall toward the feed roller 7 by utilizing their own weight, and the originals are sequentially sent to the original platen 2.

If the document is fed manually, the document can be fed reliably by inserting the document into the feed roller section.
However, when feeding a large number of documents one on top of the other, there is no problem if the documents fall onto the feed roller 7, but for some reason they may be sucked into the paper feed table 5.
The document may not fall onto the feed roller 7. The above causes include electrostatic force, friction, etc. Therefore, it becomes impossible to feed the original on the paper feed table 5 to the document table 2.

The present invention also applies to the automatic document feeder as described above.
An object of the present invention is to provide an automatic document feeder that can perform optimal and reliable paper feeding.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An automatic document feeder according to the present invention will be described below with reference to the drawings. FIG. 2 is a sectional view showing the automatic document feeder of the present invention. This automatic document feeder 3 is provided opposite to the document table 2 of the copying machine main body 1 shown in FIG.

The internal structure of the automatic document feeder is such that a document guide roller 8 is rotatably provided on a frame within a casing via a shaft, and document guide plates 9, 10, and 11 are provided opposite the circumferential surface of this roller 8. It is being The document guide plates 9 and 10 are attached to the document feed table 5 side, and the document guide plate 11 is fixed to the main body of the feeding device. Further, rollers 12 and 13 are provided opposite to the document guide roller 8, and the roller 12 is rotatably provided on the document holding table side.
Further, the roller 13 is rotatably provided on the feeder main body side.

A conveyor belt 27 is provided at the outlet of the document guide roller 8 and the document guide plate 11 to convey the document that has been guided facing each other to the exposure surface 2 . This conveyor belt 27 is located facing the entire surface of the exposure surface 2, and has a drive roller 15 and a driven roller 16.
A tension roller 17 applies an appropriate tension as appropriate. Further, a document feed roller 18 is provided opposite the entrance portion of the document guide plates 9 and 10. The document feed roller 18 is rotatably attached to a frame at the tip of the document feed table 5, and is rotated in a direction to feed the document toward the guide roller. A separation roller 19 is provided opposite the document feed roller 18 to prevent two documents from being fed. This separation roller 19 is
Unlike the document feed roller 18 described above, it is a reversing roller that is rotationally driven in the direction of returning the document.
is rotatably attached to the frame.
The frame that rotatably holds the rollers 18 and 19 is shown as 20 in FIG. It is rotatably held on the axis of the guide roller 8. Therefore, this frame 20
The document guide plates 9 and 10 and the auxiliary roller 1 described above
2nd class is attached.

Here, the roller shaft _18-1 of the feed roller 18 is supported by a retaining plate _20-2 rotatably attached to the frame 20 via a bearing 14. The holding plate _20-2 has pin 2
It is rotatably provided on the frame 20 at _0-1 . Also, the bent piece _20-3 of the holding plate _20-2
An adjustment screw _20-4 for adjusting the distance between the feed roller 18 and the separation roller 19 is attached to the. The tip of the adjustment screw _20-4 is in contact with a fixing plate _20-5 fixed to the frame 20. In addition, the bent piece _20-3 has a spring _20-6.
is installed, and this spring _20-6
The other end is attached to _20-7 fixed to the frame 20. Therefore, by turning the adjustment screw _20-4 , the retaining plate _20-2 can be adjusted to the pin 20-4.
₁ , and the distance between the feed roller 18 and the separation roller 19 is adjusted.

Further, in FIG. 2, reference numeral 21 is placed at the entrance of the document guide plates 9 and 10 via a mounting member (not shown) fixed to the frame 20 on the paper feed tray side, and the document is fed into A detector for detecting the original; 22 is a regulating plate provided on the original holding table so as to be slidable in the width direction of the original and regulating both sides of the original; 23 is a drive source for transporting the original. Motors 24 and 25 are electromagnetic clutches for driving and controlling drive rollers, guide rollers, etc.;
is a detector for detecting the document sent onto the exposure surface 2, and is fixed to the main body of the feeding device at that position in order to position the leading edge of the document at a prescribed position on the exposure surface 2. The detectors 21 and 26 are detection means such as a micro switch or an optical detection element consisting of a light emitting/receiving element, and may be other detection means.

Note that the rotational force of the motor 23 is
4 and 25 to each roller and belt. That is, when the electromagnetic clutch 24 acts, the drive belt 3 is connected to the pulley directly connected to the shaft of the guide roller 8.
Since the guide roller 8 is stretched, the guide roller 8 is rotationally driven. The drive belt 38 also transmits driving force to the pulley 28 directly connected to the shaft of the drive roller 15, and drives the conveyor belt 27. On the other hand, the electromagnetic clutch 25
8 and the separation roller 19.

In addition to the above-described configuration, the present invention further includes an auxiliary roller 29 that is rotated using the rotational force of the feed roller 18 as a driving source, as shown in FIG. The auxiliary roller 29 is rotatably supported by the holder 30. A rubber belt 32 is stretched between the auxiliary roller 29 and the feed roller 18 via a tension roller 31 provided on a holder 30. Further, the holder 30 has an arm portion _30-1 integrally molded therewith and is formed in the same shape as the roller circumferential surface of the feed roller 18 _. It is designed to rotate around the center. For this purpose, the retainer 30
is held on the circumferential surface of the feed roller 18 by the tension of a rubber belt 32 provided between the circumferential surface of the feed roller 18 and the auxiliary roller 29 . In other words,
The holder 30 is connected to the feed roller 1 by a rubber belt 32.
8 and feeds the auxiliary roller 29 to the roller 1
It is rotated along with the rotation of 8. Moreover, as the feed roller 18 rotates, the holder 18 in contact with the circumferential surface of the feed roller 18 descends due to the frictional force of the roller 18 and the rotational force of the rubber belt 32, and the auxiliary roller 18
9 is configured to descend to the document surface on the paper feed table 5. Further, the holder 30 is provided with springs 33, 33 for moving the auxiliary roller 29 away from the paper feeding surface. The springs 33, 33 are attached between the holder 30 and the fixing rod 34 between the frame 20. This fixing rod 34 is
The protruding piece _30-2 integrally provided on the holder 30 is a stopper that opposes and restricts further rotation by the spring 33 of the holder 30.

In the automatic document feeder configured as above,
The effect will be explained below.

First, if the originals to be copied are all of the same size, the originals are placed on the original paper feed table 5, and both sides of the originals are regulated by the regulating plates 22. When the placement and regulation are completed, the document feed table 5 is lifted and held at the position shown by the solid line in FIG. Note that the original may be set with the original feeding table 5 tilted. However, it may be easier to operate it if it is set horizontally.

When the above-mentioned operation is completed, a signal is output from the copying machine main body to convey the original on the holding table to the exposure surface 2, and the electromagnetic clutch 25 is activated, and the motor 2 is activated.
3 is transmitted, and the document feed roller 18 and separation roller 19 are rotationally driven. As a result, the uppermost document is fed into the feeding device 3 by the document feed roller 18, and the documents are fed one by one by the action of the separation roller 19. At this time, when the fed document is detected by the detector 21, the action of the electromagnetic clutch 25 is stopped via the delay means.
As will be explained later, the electromagnetic clutch 24 is also in operation at the same time, and the document guide roller 8 and the conveyor belt 14 are driven. Therefore, the fed document is transferred to the guide roller 8 and the conveyor belt 1.
4, it is conveyed onto the exposure surface 2. When the leading edge of the document conveyed to the exposure surface 2 is detected by the detector 26, the action of the electromagnetic clutch 24 is stopped.
Document transport is stopped. That is, the position of the exposure surface of the document is set at a prescribed level. Thereafter, when the exposure of the original on the exposure surface 2 is completed, both electromagnetic clutches 24 and 25 act, and the original on the exposure surface 2 is ejected onto the tray 4. Further, the document waiting at the paper feed port is conveyed to the exposure surface 2 via the feed roller 18 and the guide roller 8. This operation is automatically repeated, and copies of the originals placed on the original document feed table 5 are sequentially executed.

Here, the operation when feeding the original on the original document feed tray 5 into the interior will be explained in detail. That is, by the action of the electromagnetic clutch 25, the auxiliary roller 29 is rotated as the feed roller 18 rotates. On the other hand, as the feed roller 18 rotates, the holder 30 held on the peripheral surface of this roller also tends to rotate in the same direction. In this case, the feed roller 18 and the holder 30
Frictional force with arm part _30-1 and rubber belt 2
9, the holder 30 moves to the feed roller 18.
descend in the direction of rotation. Therefore, spring 3
3, the holder 30 descends to the paper feed tray 5 surface. The situation is shown in FIGS. 4a, b, and c. In other words, a is the state before the feed roller 18 rotates, and there is a considerable distance between the paper feed tray 5 and the auxiliary roller 29, which does not pose any problem in setting the original. b shows a state in which the auxiliary roller 29 is lowered by the rotation of the feed roller 18. That is,
Since the holder 30 is pressed against the circumferential surface of the feed roller 18 by the tension of the rubber belt 29, it rotates around the shaft _18-1 due to the frictional force with the feed roller 18 and descends to the paper feed table 5. . Further, the rotational force of the rubber belt 32 acts to rotate the holder 30 in the rotational direction of the belt 32, and the holder 30 descends together with the above-mentioned frictional force. Furthermore, c shows a state in which the auxiliary roller 29 is in contact with the document. In state c, the auxiliary roller 29 forcibly feeds the document to the feed roller 18. Therefore, the document on the paper feed table 5 is transferred to the feed roller 18.
Even if the document is not in the original position, it is forcibly fed by the auxiliary roller 29, and the document can be reliably fed to the last document.

As explained above, according to the automatic paper feeding device of the present invention, an auxiliary roller that rotates in conjunction with the feed roller is provided, and the auxiliary roller is lowered to the paper feeding surface by the rotation of the feed roller. Therefore, regardless of the placement of the paper on the paper feed tray, the paper on the paper feed tray can be reliably fed to the feed roller by the rotation of the auxiliary roller. Further, the configuration for lowering the auxiliary roller to the paper feeding surface on the paper feeding tray becomes very simple.

In this embodiment, a device for feeding a document to a document table in a copying machine has been described, but the present invention is not limited to a copying machine, and can of course be applied to, for example, a facsimile machine.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view for explaining the outline of an automatic document feeder according to the present invention, FIG. 2 is a cross-sectional view showing an embodiment of the automatic document feeder according to the present invention, and FIG. Enlarged perspective view of main parts in Figure 2, No. 4
Figures a, b, and c are diagrams showing how the present invention operates. 5... Document feed table, 18... Feed roller, 19... Separation roller, 29... Auxiliary roller, 30... Holder, 3
0- ₁ ...Arm part, 32...Rubber belt, 33...Spring.

Claims (1)

[Claims] 1. A paper feed tray 5 on which a large number of sheets can be placed; a feed roller 18 provided opposite to the paper feed port to feed the paper on the paper feed tray; a holder 30 which is arranged to face each other and is formed in the same shape as the rotating peripheral surface of the feed roller and slides on the peripheral surface of the roller; an auxiliary roller 29 rotatably provided on the holder; A spring 33 biases the auxiliary roller in a direction away from the paper feed table to separate the auxiliary roller from the paper; and a spring 33 that is tensioned between the feed roller and the auxiliary roller to transmit the rotational force of the feed roller to the auxiliary roller. a belt 32 for holding the holder on the circumferential surface of the feed roller; and a stopper 34 for stopping rotation of the holder by the biasing force of the spring; An automatic paper feeder characterized by a structure in which the paper is lowered by the frictional force of a feed roller and the tension of a belt, and an auxiliary roller is brought into contact with the paper on a paper feed tray to forcibly feed the paper.