JPH04217522A - Document feeder - Google Patents

Abstract

PURPOSE:To effectively carry out the operation of paper sheet handling by easily feeding a document in a document tray of such as electronic copy machine, and by forming a paper sheet handling mechanism out of upper and lower operational means of a bottom plate. CONSTITUTION:A belt carrier means 10 is provided on the paper sheet loading part of a document tray 2, so as to prepare a next document on the rear part of a fed one, and the document feeding operation is thus not stopped in the middle. A bottom plate 15 for pressing the document to a feed roller 4, is supported by a retard belt 20, and paper sheet handling is carried out between the belt 20 and the feed roller 4. After the document feeding, by returning the belt 20, the document left for handling will be returned to a tray.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a document feeding device in an image reading device configured to feed documents stored in a document tray from the top thereof.
The present invention relates to an apparatus in which a document tray is provided with a belt device for conveying documents, so that documents can be replenished toward a paper feeding section, and reading operations can be performed efficiently.

0002

2. Description of the Related Art An image forming apparatus such as an electronic copying machine is provided with means for scanning an image of a document.
It is configured to transmit image information of a document as a light or electric signal to a recording section to create recording paper. The image forming apparatus is provided with a document feeding device such as an automatic document feeder, and is provided with means for feeding documents placed on a document tray one by one toward a reading section. There is.

[0003] In a document feeding device used in a general image forming apparatus, for example, as shown in Japanese Unexamined Patent Application Publication No. 1-181652, documents are sequentially fed out from the bottom of the documents stacked on a document tray. A method is used in which the paper is sent through a paper handling device to a reading unit. The means for feeding documents from the bottom of the document is commonly used not only in electronic copying machines but also in devices such as general facsimile machines.

However, in the above-mentioned document feeding device, the weight of the documents deposited on the document tray is applied to the feed roller provided in the paper feeding section.
There is a problem in that when a document is fed out by the feed roller, the pressure exerted by the document affects the feeding performance by the feed roller. Therefore, in the document feeding device as described above, the amount of documents that can be placed on the document tray at one time is 30.
There is a problem that it is limited to about 100 sheets.

In order to solve the above-mentioned problem, it has been proposed, for example, as disclosed in Japanese Utility Model Application Publication No. 1-137928, to feed documents from the top of the documents stored in the document tray. By using the above-described paper feeding means, it is possible to easily feed a large number of documents to a high-speed image reading device while storing a large number of documents in the document tray at one time.

[0006]

[Problems to be Solved by the Invention] However, in the conventional apparatus described above, in order to store a large number of documents in the document tray, the tray becomes large, and in order to move the tray up and down, it becomes complicated. Since it is necessary to use a drive mechanism with a specific configuration, there is a problem that it is difficult to apply it to a general image reading device. In addition, in a paper feeder that feeds paper from the top of the document,
It is not possible to replenish the document while the feeding operation is in progress; with high-speed scanning devices, it is necessary to temporarily stop the scanning operation and replenish the document after the document tray is empty. Therefore, there is a problem that reading efficiency is hindered.

On the other hand, when using a device that feeds paper from the bottom of the document tray, such as that used in facsimiles, the number of documents that can be set at one time is limited to about 30 sheets. In high-speed reading devices, it is necessary to frequently replenish documents, which increases the burden on the operator.

[0008]

OBJECTS OF THE INVENTION The present invention solves the above-mentioned drawbacks of the conventional apparatus, and is capable of replenishing originals by providing a conveyor belt device in the original tray and preparing the next original. In addition to configuring it so that it can be easily carried out, the structure of the paper feeding device can be simplified by configuring a mechanism that presses the document toward the feed roller using the retard belt that makes up the paper handling device. The aim is to provide a device that

[0009]

[Means and effects for solving the problems] The present invention provides a feed roller disposed above a paper feeding section of a document tray, and a bottom plate that pushes up the document toward the feed roller. This invention relates to a device that feeds documents from the top.

[0010] In the document feeding device of the present invention, a plurality of belts for conveying documents are arranged in the document conveying direction on the document supporting surface of the document tray, and the belts for conveying documents are arranged in plural strips in the document feeding section of the document tray. The bottom plate is configured such that the bottom plate is arranged in a comb tooth shape, and means is provided for swinging the paper feed side tip of the bottom plate toward the feed roller. The means for swinging the bottom plate is constituted by a retard belt, and the retard belt and the feed roller constitute a paper handling mechanism.

Further, in the apparatus of the present invention, the retard belt used for swinging the bottom plate in the paper feeding section of the document tray is composed of a band-shaped member, and one end of the belt is attached to the bottom plate. the other end of which is connected to the drive means, and is guided via a guide roller disposed at a position facing the feed roller; The paper handling function is configured between the feed belt and the feed roller. With the configuration as described above, in the document feeding device of the present invention, there is a
By preparing the next document, the document can be fed continuously without being interrupted, and the reading efficiency of the image reading device can be improved.

In addition, in the apparatus of the present invention, since the means for swinging the bottom plate is constituted by a retard belt, it is possible for originals to enter the handling section in a double-feed state, and the lower original to be removed from the handling section. Even if the original is stopped and remains, the original can be returned to the original tray when the bottom plate is returned, so the leading edge of the original can be easily positioned.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of a document feeding apparatus according to the present invention will be explained according to the illustrated example.

The embodiment of the present invention shown in FIGS. 1 to 3 includes a paper feed section 3 provided for a document tray 2 of a document feeder 1, a conveyor belt 10, a bottom plate 15, and a retarder. This shows the positional relationship of the belt 20.
The length L of the document placement portion of the document tray 2 is configured to match, for example, the longitudinal direction of A3 size. A conveyor belt 10 placed on the document placement surface of the document tray 2 is supported by pulleys 11 and 12 placed at the front and rear ends of the document tray 2, and two guide belts are provided at the intermediate portion thereof. It is guided by rollers 13 and 14 and is arranged to be inclined downward on the front side in the paper feeding direction. The conveyor belt 1
One of the front and rear pulleys 11 and 12 supporting 0 is
It is configured as a driving pulley, and the other pulley is a driven pulley and is provided with means for applying tension to the conveyor belt.

The document tray 2 is provided with sensors s1 and s2 in order to detect the presence or absence of documents, and one of the two sensors, s1, is arranged at a rear document replenishment position. However, another sensor s2 is provided on the bottom plate 15. Then, these two sensors detect the document being fed and the next document that can be replenished, and when all the documents on the bottom plate have been fed out, the next document is sent. When it is in the standby position, the conveyor belt is driven to feed the next document to the paper feeding position.

Further, on the paper feeding side from the document tray 2, a bottom plate 15 for supporting the document and moving it up and down is provided via a support shaft 16.
A retard belt 20 is connected to the leading end of the paper feed side. The retard belt 20 is made of a felt band-like member, a rubber belt, etc., and is extended forward on the paper feeding side via a guide roller 21 and connected to a drive pulley 22. The drive pulley 22 is driven by a motor 23 to drive the retard belt 20.
By winding up the bottom plate 15, the bottom plate 15 is swung. Further, a feed roller 4 is disposed on the upper part of the paper feed section 3 from the document tray 2.
Although the guide roller 21 is disposed at a position facing the roller, both roller members are disposed with a slight deviation. The retard belt 20 supported by the guide roller 21 and the feed roller 4 constitute a paper sorting device. Furthermore, in an embodiment of the present invention,
In the paper handling device, a gap d of about one sheet of original paper is provided between the feed roller 4 and the retard belt 20, and the paper feed section 3 performs the feeding action on the original. When performing this, the setting is such that one document is allowed to pass, but two documents are not allowed to pass.

In the document feeding apparatus of the present invention constructed as described above, when feeding a document from document tray 2, as shown in FIG. By winding 20 around the pulley 22,
The sending end of the bottom plate 15 is lifted to set a state in which the document supported on the bottom plate 15 is pressed toward the feed roller 4. When the device feeds paper, the bottom plate 15 is projected above the conveyor belt 10, so that the lower surface of the document is held at a position separated from the conveyor belt.

The relationship among the conveyor belt 10, bottom plate 15, and retard belt 20 shown in FIG. 1 is constructed as shown in the perspective view of FIG. 3. As shown in FIG. 3, the conveyor belt 10 disposed on the document tray 2 is composed of a plurality of narrow belts,
A guide roller 13 provided coaxially with the support shaft 16 of the bottom plate 15 defines an inflection section in the conveyance section. Further, a bottom plate 15 arranged in a comb-teeth shape between and on both sides of the conveyor belt is connected to the retard belt 20 at its tip end on the sheet feeding side, and serves as a driving means for the retard belt 20. It is configured to be swung by.

In the original document feeding apparatus of the present invention configured as described above, when sending out originals, the first group of originals p is first fed into the sheet feeding section as shown in FIG.
1 is set, and the feed roller 4 feeds the document. Then, the first group of manuscripts p
While the tray 1 is being sent out, the tray 2 is placed behind the tray.
The document p2 of the group is placed. In this state, two sensors provided on the document tray each output a document presence signal to the control device.

When all the documents of the first group have been sent out, the sensor s2 provided on the bottom plate 15 outputs a signal indicating that there is no document, and when the sensor s1 outputs a signal indicating that there is a document, the control device A signal for driving the conveyor belt 10 is output, the drive pulley is driven, and the document p2 of the next group is sent toward the paper feed section using the conveyor belt 10, and the document p2 is fed from the document p2. to start immediately. In FIG. 4, in the case of the present invention, the document abutting portion 2a is a position set by the retard belt 20, and the leading edge of the document is pressed against the rising portion of the retard belt 20. By doing so, the leading edge of the document can be positioned.

FIG. 5 shows an example of an image reading device incorporating the document feeding device of the present invention. In addition, in Figure 5,
Although the conveyance belt is omitted from the illustration, the conveyance belt is arranged with respect to the document tray 2 in the same manner as shown in FIG. In the image reading device shown in FIG. Paper is fed while being pressed against the paper. Then, the feed roller 4 and the guide roller 21
A paper handling action is performed between the original and the retard belt supported by the retard belt, and the original is sent out toward the original transport path 5. A sensor s3 for detecting the original ejected from the paper feeding section and transport roller devices 6 and 7 are disposed in the document transport path 5, and the transport roller device transports the original to the reading section. The document is conveyed toward a platen 8 , and the image on the document is scanned by a reading device disposed below the platen 8 .

In the paper feeder of the present invention, when feeding a document by the feed roller 4, the motor 23 is driven by a paper feed signal from the control device, and the pulley 22 is used to feed the document. Make sure to wrap the retard belt 20. In addition, by pulling up the bottom plate 15 toward the feed roller, the document p1 supported by the bottom plate is
Make sure to send out the one at the top. Then, when the leading edge of the document passes through the sensor s3 and is nipped by the transport roller device 6, the drive to the feed roller 4 is stopped, and the bias to the motor is released. , the bottom plate is lowered by its own weight.

By the above-described lowering operation of the bottom plate, the retard belt 20 is pulled out from the pulley 22 and returned to the tray through the paper handling section. At this time, even if there is a double-fed document in the paper sorting device, the document will be moved into the tray together with the retard belt 20, so the document will not be fed in the paper sorting device. There will be nothing left. Furthermore, as described above, when returning the document to the tray, the portion of the paper handling device of the present invention is supported by the feed roller 4 and the portion of the retard belt 20 that is supported by the guide roller. There is a gap about the size of one document between them, so when returning the document, the document can be moved into the tray by following the retard belt without having to reverse the feed roller. .

In the document feeding apparatus of the present invention configured as described above, when carrying out an operation in which a large number of documents are continuously fed toward the reading section, for example, 20
By grouping around 0 originals into one group and replenishing the rear of the paper feed section with the next document each time there is space at the rear, you can easily feed the originals toward the image reading section without interrupting the document feeding process. It is possible to feed paper continuously.

In the document feeding apparatus of the present invention, the length L of the document tray can be configured to correspond to, for example, an A3 size document; It is possible to divide the paper into two groups and replenish them sequentially, but for A3 size documents, just like with conventional document trays, the paper can be fed to one group. Once completed, the operation of the image reading device will be interrupted. On the other hand, when the document tray is constructed as a large-sized document tray, it becomes possible to continuously supply documents of a size larger than A4 size documents. In addition, in the document tray of the present invention, the number of conveyor belts, the number of bottom plates, the width of the retard belt, etc. can be arbitrarily set according to the paper quality of the document, etc. The coefficient of friction of the retard belt against the paper can also be set arbitrarily depending on the paper quality of the document.

[0026]

[Effects of the Invention] Since the document feeding device of the present invention is constructed as described above, it is necessary to provide means for moving the document within the document tray, and to use the bottom plate as a paper sorting device. By using means for moving the document tray up and down using a retard belt, the mechanism of the document tray can be simplified. Further, in the document feeding device of the present invention, by preparing the next document at the rear of the paper feeding section of the document tray, the document feeding operation can be performed continuously without interruption. This makes it possible to improve the reading efficiency of the image reading device.

Furthermore, in the apparatus of the present invention, since the means for swinging the bottom plate is constituted by a retard belt, documents may enter the separation section in a double-feed state, and the document below may stop. Even if the bottom plate is returned, the original can be returned to the original tray by following the retard belt, so the leading edge of the original can be easily positioned.

[Brief explanation of the drawing]

FIG. 1 is a side view showing the configuration of a document feeding device according to the present invention.

FIG. 2 is an explanatory diagram of the bottom plate of the present invention in a state where it is swung to a paper feeding position.

FIG. 3 is a perspective view of the document tray of the present invention.

FIG. 4 is an explanatory diagram of the operation of adding documents in the document tray of the present invention.

FIG. 5 is an explanatory diagram of an image reading device to which the document feeding device of the present invention can be applied.

[Explanation of symbols]

1 Original feeding device 2 Original tray 4 Feeder roller 10 Conveyor belt 15 Bottom plate 20 Retard belt 21 Guide roller

Claims (1)

[Claims] [Claim 1] A device in which a feed roller is disposed above a paper feeding section of a document tray, the document is pushed up toward the feed roller by a bottom plate, and the document is fed from the top of the document. , on the document support surface of the document tray,
Multiple belts for document conveyance are arranged in the document conveyance direction,
At the paper feed section of the document tray, the conveyor belt and bottom plate
The bottom plate is configured such that the feed rollers are arranged in a comb-tooth shape, and a means for swinging the paper feed side tip of the bottom plate toward the feed roller is provided. 1. A document feeding device characterized in that a means for swinging a sheet is constituted by a retard belt, and a sheet handling mechanism is constituted by the retard belt and a feed roller.