JPS59194948A - Automatic paper-sheet feeding apparatus - Google Patents

Abstract

PURPOSE:To stably correct the oblique advance of a paper sheet by temporarily stopping a sheet of transported paper and idly revolving, for a certain time, a resistor roller for starting transportation, and then executing automatic paper feed. CONSTITUTION:Cut paper-sheets 1 are stored in a paper-sheet feeding cassette 2 and pressed onto a pick-up roller 5 by the force of a spring 4 through a bottom plate 3. Said cut paper-sheet 1 is driven-out by the revolution of the above- described roller 5 and separated one by one by a separating hook 6. Then, the cut paper sheet 1 introduced into a feeding roller 8 along an entry guide 7 reaches a resistor roller 10 along a guide 9. In this case, deformation of the frictional member on the surface of the resistor roller 10 is prevented by revolving the resistor roller 10 in the state where the cut paper sheet 1 is not transported without revolving the pick-up roller 5. Thus, correction for the oblique advance of the cut paper sheet 1 is executed stably by the resistor roller 10.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an automatic paper feeder in a paper sheet processing apparatus such as a copying machine or a printer, and more particularly to a paper sheet skew correction device. The present invention relates to an automatic paper feeder having the following.

[Background of the invention]

FIG. 1 shows an example of an automatic sheet feeder that has been used in the past to feed sheets one by one from a stack of sheets. Cut paper 1 is stored in a paper feed cassette 2, and a bottom plate 3
is pressed against the pickup roller 5 by the force of the spring 4. As the pickup roller 5 rotates, the cut paper 1 is ejected from the paper feed cassette 2.

At this time, the cut paper 1 is separated one by one by the action of the separation claw 6. The cut paper 1 guided by the entry guide 7 to the feed roller 8 is conveyed by the feed roller 8,
It is guided by a guide 9 and reaches a register roller 10. At this point, the register roller 10 is stopped without rotating, so the cut paper 1 continues to receive the conveyance force from the feed roller 8.
is pressed against the register roller 10 and deforms as shown by the broken line 11. When the cut paper 11 is bent in this way, the leading edge of the cut paper 11 is uniformly pressed against the register roller 10, and the skew of the cut paper 11 is corrected. After the skew correction is completed, the register rollers 10 start rotating, and the cut paper 11 is conveyed by the conveying force of the register rollers 10.

The operation timings of the pickup roller 5, the feed roller 8, and the register roller 10 are determined to be interlocked in this manner. Here, in order to correct the skew of the cut paper 11, the register rollers 10 are pressed against each other with an appropriate force. If this pressing force is insufficient,
The cut paper 11 receiving the conveyance force from the feed roller 8 is
Will it pass through without being stopped by the register roller 10?
Or, it passes through only a portion and then stops. In this case, correction of skew becomes insufficient. Furthermore, if the cut paper 1 to be conveyed is made of a material that does not easily bend, such as cardboard, it will more easily pass through the register rollers 10. Therefore, it is necessary to determine the pressing force of the register roller 10 in consideration of the stiffness of the target cut paper 1. On the other hand, since the register roller 10 also has the role of conveying the cut paper 11 that has undergone skew correction, both or only one of the register rollers 10 has its surface covered with a friction member such as rubber. Therefore, when the device is stopped, the register roller 1
If the time that 0 is stopped becomes longer, the register roller 1
0, the same parts remain pressed together, and deformation due to so-called creep may remain in the friction member on the surface. Moreover, this deformation is not uniform in the axial direction of the register roller 10. This is because the material of the friction member is not necessarily uniform and the pressing force of the register roller 10 differs depending on the position. When attempting to correct the skew using the register roller 10' whose surface remains deformed in this way, when the leading edge of the cut sheet 11 comes into contact with the deformed portion of the register roller 10 and stops, it is cut following the unevenness of the friction member. Since the paper 11 stops, correction of skew feeding may not be successful. In other words, the conventional device has a drawback in that if the V dimeter roller 10 is stopped for a long time, the subsequent skew correction may become insufficient.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned drawbacks and to improve an automatic paper feeder so as to enable stable skew correction.

[Summary of the invention]

In order to achieve the above object, the automatic paper feeding device of the present invention allows the register roller 10, which has been deformed due to creep during the stop period, to idle, and then automatically feeds the paper. This takes advantage of the fact that if the register roller 10, which is partially deformed, is allowed to rotate for a while, the register roller 10, which is less deformed, returns to its original shape.

[Embodiments of the invention]

An embodiment of the present invention will be described below. The structure of the automatic paper feeder according to the present invention is shown in FIG. 1, and has the same structure as conventionally used devices. Therefore, as described above, if the register roller 10 is stopped for a long time, the friction member on the surface of the register roller 10 will be deformed. In this apparatus, the deformation of the register rollers 10 is removed by rotating the register rollers 10 without conveying the quad paper 1. That is, the deformation of the register roller 10 is removed by rotating the register roller 10 without rotating the pickup roller 5.

This principle will be explained. Now, when the present automatic paper feeder is operated after a long period of stoppage, the register roller 10 is rotated as a break-in operation. At this time, pickup low 2
5 does not rotate, the cut paper 1 is not conveyed even to the box in which the paper feed cassette 2 is attached. The register rollers 10, which had some deformation left on their surfaces, will gradually return to their original shape as they rotate around their entire circumferences while being pressed against each other during a break-in operation to reverse their elastic deformation. It will regain its shape. In this way, the deformation of the surface of the register roller 10 is removed, and then automatic operation is started. The register roller 10 with surface deformation removed in this manner can achieve the original skew correction effect.

When trying to perform the break-in operation of the register roller 1o for the above-mentioned purpose using a conventional device, the operation timing of the register roller 10 is different from that of the pickup roller 5 and the feed roller 8.
Since the operation timing is interlocked with the operation timing of the register roller 10, when the register roller 10 is operated, the pick-up roller is also driven, and as a result, the cut sheet 1 is conveyed. In order to prevent this, it is necessary to once remove the paper feed cassette 2 and remove the cut paper 1. To save this time,
In the apparatus according to the present invention, apart from the daily operation of actually transporting the cut paper 1, it is possible to perform an operation of rotating the register roller 10 while the pickup roller 5 is stopped. The shaft of the pickup roller 5, the shaft of the register roller 10, and the feed roller 8
The shafts of the register rollers 10 are each connected to a main motor (not shown) via a clutch, and during the break-in operation of the register rollers 10, only the clutch of the shaft of the register rollers 10 is engaged to realize the break-in operation.

The engagement states of the clutches during automatic paper feeding and break-in operation are shown in FIGS. 2 and 3. Figure 2 shows the case where automatic paper feeding is performed, and the signal al is the pickup roller 5.
, the symbol a2 indicates the operation signal of the feed p roller 8, and the signal a3 indicates the operation signal of the register roller 10. At time O, the clutches connected to the shafts of the pickup roller 5 and the feed roller 8 are engaged, the pickup roller 5 and the feed roller 8 rotate, and the cut paper 1 is ejected from the paper feed cassette 2. At time 11, the clutch connected to the shaft of the pickup roller 5 is disengaged, but at this time the cut paper 1 has already reached the feed roller 8.

Therefore, the cut paper 1 is conveyed by the feed roller 8, so that the shaft of the pickup roller 5 is rotated by the cut paper 1. The feed roller 8 stops rotating at time t2 when the cut sheet 1 reaches the register roller 1o and is further bent. At this time, the register roller 10
is stopped, and the above-mentioned skew of the cut paper 1 is corrected. After a while, the clutch connected to the shaft of the register roller 10 is engaged from time t3, and the cut paper 1 is conveyed. The cut sheet 1 has left the register roller 10 before time t4. Time t4
The series of automatic paper feeding operations is completed, and the process begins to automatically feed the second sheet. FIG. 3 shows a case where a break-in operation is performed, and the signal bt indicates the operation signal of the pickup roller 5, the signal b2 indicates the operation signal of the feed roller 8, and the signal b3 indicates the operation signal of the register roller 1o. During the break-in operation, the clutches connected to the shafts of the pickup roller 5 and the feed roller 8 are always disengaged and do not transmit rotation. and register roller 1
Only the clutch connected to 0 is engaged, and the register roller 1o is driven. In this way, the break-in operation is made possible by switching the operating timing of each clutch during automatic paper feeding and during the break-in operation. In the above embodiment, the feed roller 28 is stopped during the break-in operation, but it is clear that the feed roller 8 may be driven. Further, in the above embodiment, the main motor is connected to each clutch, but it is not necessary that there is only one main motor, and a plurality of motors may be used. The present invention can also be experimented with a configuration in which a plurality of motors are driven independently and a clutch is not used.

〔Effect of the invention〕

As described in detail above, according to the present invention, it is possible to realize an automatic sheet feeder that can perform stable skew correction even immediately after the start of operation (9).

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional view of a general automatic paper feeder, and FIGS. 2 and 3 are diagrams showing the operation timing of each clutch during automatic paper feeding and break-in operation in the automatic paper feeder of the present invention. be. 1... Cut paper, 2... Paper feed cassette, 5... Pick up roller, 8... Feed roller, 9... Guide, 10... Registration roller. (10) Figure 1 Figure 2 Figure A 3

Claims (1)

[Claims] A pickup roller that sends out the paper leaves from a hopper with piled up paper leaves, a register roller that temporarily stops one paper leaf being conveyed and then starts conveying it, and guides the paper leaf to the register roller. An automatic paper feeder including a guide, characterized in that the register roller is controlled to idle for a certain period of time without transporting the paper, and then automatically feeds the paper.