JPH048343B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a sheet feeding device installed in a sheet intake port provided in an image forming apparatus such as a copying machine, a laser printer, a liquid crystal printer, or a printing machine; The present invention relates to a sheet conveyance device such as an automatic document feeder that automatically feeds a document onto a platen of an image processing device such as a copying machine, facsimile machine, or image reader.

[Conventional technology]

Conventionally, an automatic document feeder installed in an image processing device, such as a copying machine, feeds a document loaded on a document tray by rotating the document in the document conveyance direction and feeding the document, and an automatic document feeder that faces the document feed roller. A separation roller is provided, which rotates in the opposite direction to the direction in which the document is transported, and removes the document sent out by the feed roller.The document is separated and sent out one by one, and this document is sent onto the platen with a conveyance belt. When the document is set at the reference position and copying is completed, the document is ejected from the platen by a conveyor belt and stored in a paper ejection tray.

[Problem that the invention seeks to solve]

In such an automatic document feeder, if multiple documents are fed (double feed), some documents will not be copied, so improvement in separation performance is required.

Furthermore, since the separation roller rotates in a direction that prevents the document from being conveyed, it is difficult to grip the document, and the document is likely to skew when gripped.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a sheet conveying device that improves separation performance and prevents sheet skew.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention provides a sheet conveying device that separates and conveys a plurality of sheets into one sheet. a first separation means for rejecting the sheet following the sheet conveyed by the first feeding means; a second feeding means for conveying the sheet conveyed by the second feeding means; a second separating means for rejecting the sheet following the sheet conveyed by the second feeding means; the first separating means and the second separating means;
a deflection space provided between the first feeding means and the first separating means, in which the sheet can be deflected;
When the sheet sent out while being separated by the separating means reaches between the second feeding means and the second separating means, the second feeding means is stopped or the sheet is sent out while being separated by the separating means. means for imparting deflection to the conveyed sheet by rotating it at a rotational speed lower than the rotational speed of the second feeding means, and for rotating the second feeding means at a predetermined rotational speed after imparting the deflection; Equipped with

[Effect]

Therefore, the sheet is separated by the first feeding means and the first separating means, and is brought into contact with the second feeding means and the second separating means, and the leading edge of the primarily separated sheet is registered before being fed. Since the secondary separation is performed by the means and the separating means, the skew caused by the primary separation can be corrected.
In addition, since the double-fed sheet in the primary separation is bent in the space between the first separation means and the second separation means, a gap is created between the conveyed sheet and the double-fed sheet, and there is a gap between the sheets. The adhesiveness disappears and separation becomes easier, improving separation performance.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings.

<Structure> As shown in FIG. 1, an automatic document feeder 75 is mounted on a platen 77 of an image processing apparatus, such as a copying machine 7.

This automatic document feeder 75 is connected to the document tray 20.
7, and a separating and feeding unit 209 that separates the original set on the original tray 207 into one sheet and sends it out.
, a reversing unit 210 that inverts the original sent from the separation/feeding unit 209 or the original fed from the platen 77, a transport unit 211 that transports the original on the platen 77, and a transport unit 211 that transports the original that has been copied. A paper discharge section 213 that discharges paper via the reversing section 210
and a storage tray 215 for accommodating the document discharged from the paper discharge section 213, so that the document can be discharged to the side from which the document was fed.

As shown in FIG. 2, the separation feeding section 209 includes a sensor 201 that detects whether or not a document Q is set in the paper feed port 217, and a non-circular sensor 201 that sends out the document Q set in the paper feed port 217. a hard crawler 219 and a document holder 221 that presses the original Q inserted into the paper feed port 217 against the hard crawler 219.
For example, a first feeding unit is provided facing the paper feeding path 222 formed by the paper feeding guides 218 and 220, rotates in the document transport direction, and transports the original sent out by the paper crawler 219. A feed roller 253, a first separating means that rotates in the opposite direction to the document conveyance direction and rejects the document that follows the document conveyed by the feed roller 253, for example a separation roller 265, and the feed roller 253. A sensor 267 detects the document that has been separated and sent out by the separation roller 265, and a second feeder that rotates transversely to convey the document and conveys the document that is sent out while being primarily separated by the feeding roller 253 and the separation roller 265. A feeding means, for example, a feeding roller 257, and a second separation means, for example, a separation roller 269, which rotates in the opposite direction to the direction of conveyance of the original and rejects the original that follows the original that is transported by the feeding roller 257.
, a sensor 203 that detects the leading edge of a document that has been secondarily separated by a feeding roller 257 and a separating roller 269 and sent out, and a registration roller 227 that registers the leading edge of the secondarily separated document. In addition, rollers 253, 257, 265, 269
is a rubber roller, for example. Also, the separation roller 26
5 and the separation roller 269 is provided with a deflection space in which the document can be deflected.

The document holder 221 includes a first arm 245 that rotates around a shaft 243, and a first arm 245 that rotates around a shaft 243.
A second arm 249 that rotates around a shaft 247 provided at the distal end side of the
5 presses the document against the hard crawler 219,
The tip of the second arm 249 holds the tip of the document.

The reversing section 210 includes a forward/reverse roller 223 and a pressure roller 2 that is in pressure contact with the forward/reverse roller 223.
25, 229, a reversing path 231 for flipping the original and reversing the original, a sensor 232 for detecting the original, and a transport path switching guide 2.
33 and a guide 235 that guides the original on the reversing path 231 onto the platen 77 and guides the original on the platen 77 to the reversing path 231.

The conveying section 211 is attached to the back of the copying machine 7 via a hinge so that it can be opened and closed, and a document can also be set on the platen 77 by manual operation.

This conveyance section 211 includes a conveyor belt 285 stretched between rollers 281 and 283 as shown in FIG.
Pressure rollers 287, 289, and 291 are provided to press the conveyor belt 285 against the platen 77.

The paper ejection section 213 is provided with a paper ejection path 293 connected to the reversing path 231, an elastic guide 294 such as a synthetic resin sheet, a paper ejection sensor 295, and paper ejection rollers 297, 299.

<Operation> With the above configuration, this device operates as follows.

In the initial state, the wood crawler 219 is in the position shown in FIG. Further, the document presser 221 is raised.

When the original Q is inserted into the paper feed port 17 with the copy side facing up, the sensor 201 detects the original Q. Next, copy conditions are set by operating an operation panel (not shown).

When a print button (not shown) is pressed in such a state, the shaft 243 of the document holder 221 rotates clockwise as shown in the figure, and the document holder 221 holds the document Q.
fall on top. Therefore, the tip of the first arm 245 presses the document Q against the hard crawler 219,
The tip of the second arm 49 presses the tip of the document.

Further, the hard crawler 219 rotates and sends out the document Q starting from the bottom sheet. This document Q is held between a feed roller 253 that rotates in the conveyance direction and a separation roller 265 that rotates in the opposite direction to the conveyance direction. The separation roller 265 removes the particles and performs primary separation. And the primary separated original Q
is brought into contact with the rolling contact portion of the feeding roller 257 and separation roller 269, which are stopped, and a deflection is formed.

By the way, when the leading edge of the document Q is detected by the sensor 267, the feeding roller 253 and the separating roller 265 stop after a predetermined time T1. Here, the predetermined time T1 is set to a time sufficient for the leading edge of the document Q to contact the rolling contact portion of the feeding roller 257 and the separation roller 269 after passing the sensor 267, and for the document Q to bend. . Therefore, the leading edge of the original document Q, which is bent due to the primary separation, is registered.

Then, a predetermined time T is elapsed after the sensor 267 is turned on.
2 (T2>T1), the feeding roller 257 and separation roller 269 are rotated, and secondary separation is performed by the feeding roller 257 rotating in the transport direction and the separation roller 269 rotating in the opposite direction to the transport direction.

By the way, when the leading edge of the document Q is detected by the sensor 203, the feeding roller 253,
257 and separation rollers 265 and 269 stop.
Here, during the predetermined time T3, the leading edge of the document Q is at the sensor 2.
The time period is set to be sufficient for the document Q to come into contact with the rolling contact portion of the registration roller 227 and the forward/reverse rotation roller 223 after passing through 03, and for the document Q to bend. Therefore, the leading edge of the document Q that is bent due to the secondary separation is registered.

Then, a predetermined time T is elapsed after the sensor 203 is turned on.
4 (T4>T3), the forward/reverse rollers 223 are slightly rotated, the leading edge of the document is held between the registration rollers 227 and the forward/reverse rollers 223, and the document is placed on standby with no deflection.

When the copying preparation of the copying machine 7 is completed in this state, the forward/reverse roller 22 rotates in the direction of the solid line arrow.
3 and feeding rollers 257 and 253 send out the document Q. This sent out document Q is moved by the elastic guide 2
94 and the forward/reverse roller 223, and the conveyance path switching guide 23 is in the state shown by the broken line.
3 and is supplied to the reversing path 231. When the rear end of the document in the conveyance direction is detected by the sensor 232, the conveyance path switching guide 233 is switched as shown by the solid line, and the forward/reverse roller 223 is rotated in the direction of the broken line arrow. Therefore, the document is sent out with its rear end at the beginning, passing above the guide 235 and onto the platen 77.

Then, the document is conveyed over the platen 77 by the conveyance belt 285 and set at a reference position, and a copying operation is performed.

When copying is completed, the conveyor belt 285 reversely rotates and is sent from above the platen 77 to the reversing path 231 passing below the guide 235. When the trailing edge of the document is detected by the sensor 232, the conveyor belt 285 rotates in the reverse direction and is sent to the reversing path 231.
33 is switched, and the forward/reverse rotation roller 22
3 rotates in the direction of the dashed arrow.

As a result, the document switches back and forth, and the paper output path 2
93. Note that the rear edge of the document Q is the sensor 2.
32, the next document on the document tray 207 is moved in the same manner as described above.
The document waits with the leading edge of the document held between the registration rollers 227 and the forward/reverse rotation rollers 223.

The document supplied to the paper ejection path 293 is ejected onto the storage tray 215 by paper ejection rollers 297 and 299. At this time, when the trailing edge of the document is detected by the sensor 295, the previously delivered document is sent onto the platen 77.

<Effects of Example> According to this example described above, the following effects can be obtained.

(1) Separate the document with the feed roller 253 and separation roller 265 and hit it against the place where the feed roller 257 and separation roller 269 are stopped.
Since the leading edge of the separated document is registered and then the feeding roller 257 and separation roller 269 are rotated to perform the secondary separation, the secondary separation can be performed after correcting the skew caused by the primary separation.

(2) The document W double-fed in the primary separation is
As shown in FIG. 3, since the separation roller 265 and the separation roller 269 are bent in the bending space, a gap is created between the conveyed original Q and the double-feed original W, and the adhesiveness between the originals Q and W is lost. Separation becomes easier and separation performance improves.

[Modified example]

Although one embodiment of the present invention has been described above,
The present invention is not limited to the above-mentioned embodiment, and for example, the following modifications are possible.

(1) In the embodiment described above, the sheet conveying device was applied to the separation feeding section 203 of the automatic document feeder 75.
The present invention can also be applied to a separating section of a large-capacity sheet feeding device that accommodates a large amount of copy paper to be fed to a copying machine or the like.

(2) a separation roller 265 that rotates in the opposite direction to the sheet conveyance direction as the first and second separation means;
Although 269 is shown, the separation may be performed using a friction member such as a fixed rubber roller or a rubber pad. Further, the first and second feeding means and the first and second separating means may be belts or the like. Furthermore,
It is also possible to combine rollers, belts, etc.

(3) In the above embodiment, the feed roller 253 and the separation roller 265, and the feed roller 257 and the separation roller 269 were brought into contact with each other, but a plurality of each may be provided on the same axis and arranged alternately in a non-contact state. good. Further, a contact state and a non-contact state may be combined. Note that when in a non-contact state, they are provided so as to overlap each other in the diametrical direction.

(4) In the above embodiment, a device that feeds sheets from the bottom paper is shown, but the present invention can also be applied to a device that feeds sheets from the top paper.

(5) In the above embodiment, the leading edge of the document was brought into contact with the feeding roller 257 and the separating roller 269 while they were stopped, causing the document to bend.However, the feeding roller 257 and the separating roller 269 are rotated at a low speed. You can also put the manuscript somewhere.

〔Effect of the invention〕

According to the sheet conveying device of the present invention, in the sheet conveying device that separates and conveys a plurality of sheets into one sheet, the first feeding means rotates in the sheet conveying direction to convey the sheet; a first separating means for rejecting a sheet following a sheet conveyed by the feeding means; and a sheet rotated in the sheet conveying direction and sent out while being separated by the first feeding means and the first separating means. a second feeding means for conveying the sheet; a second separating means for rejecting the sheet following the sheet conveyed by the second feeding means; the first separating means and the second separating means; A bending space is provided between the bending space in which the sheet can bend, and the sheet is fed out while being separated by the first feeding means and the first separating means. When the sheet reaches between the second separating means, the second feeding means is stopped or rotated at a rotational speed lower than the rotational speed of the first feeding means to give a deflection to the conveyed sheet. In addition, since the second feeding means is provided with a means for rotating the second feeding means at a predetermined rotational speed after the deflection is imparted, it is possible not only to correct the skew of the leading edge of the sheet by deflecting the sheet, but also to correct the skew at the leading edge of the sheet. If the sheets sent out by the second feeding means are double fed, gaps will be created between the sheets when the sheets are bent, the adhesion between the sheets will be loosened, and the separation performance by the second separating means will be improved.

[Brief explanation of drawings]

1 to 3 are diagrams showing an embodiment of the present invention, in which FIG. 1 is a cross-sectional view showing the configuration of an automatic document feeder, and FIG. 2 is a configuration of the separation and feeding section of the automatic document feeder. FIG. 3 is a cross-sectional view showing the separation operation and effects. 7... Copy machine, 75... Automatic document feeder, 2
07... Original tray, 209... Separation feeding section, 2
10... Reversing section, 211... Conveying section, 213...
Paper ejection section, 219...Tight crawler, 221...Document holder, 223...Forward and reverse rotation roller, 227...
Registration roller, 231... Reversal path, 253,
257... Feeding roller, 265, 269... Separation roller.

Claims (1)

[Claims] 1. A sheet conveying device that separates and conveys a plurality of sheets into one sheet, comprising: a first feeding means that rotates in a sheet conveying direction to convey the sheet; and this first feeding device. a first separating means for rejecting a sheet following a sheet conveyed by the means; and a first separating means for rotating in a sheet conveying direction and conveying a sheet sent out while being separated by the first feeding means and the first separating means. a second feeding means; a second separating means for rejecting a sheet following a sheet conveyed by the second feeding means; and between the first separating means and the second separating means. a bending space provided in which the sheet can bend, and a sheet fed out while being separated by the first feeding means and the first separating means, a bending space in which the sheet is separated by the second feeding means and the second separating means. When the conveyed sheet reaches between the conveyed sheet and the conveyed sheet, the second conveying means is stopped or rotated at a rotational speed lower than the rotational speed of the first conveying means to give a deflection to the conveyed sheet, and and a means for rotating the second feeding means at a predetermined rotational speed after applying the deflection.