JPS6348577Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a paper feeding device such as a copying machine, a printing machine, or the like.

Generally speaking, in a paper feeding device that separates and feeds stacked sheets of paper one by one using separation rollers, feeding is not possible (infeed) or double feeding ( Problems such as double feed (double feed) occur.

To explain this in the case where the paper is separated and fed using the separation roller 1' and the double-feed prevention roller 2' in Fig. 1, the paper fed out by the delivery roller 3' is different in size and loaded, and due to the difference in paper adhesion to each other. Therefore, as shown in FIG. 1B, the leading ends are uneven and are bitten by the separation roller 1'. Therefore, if several sheets of paper are fed in close contact with each other, double feeding or failure to feed may occur.

In order to prevent such defects, it has been proposed to bend the paper using an eccentric roller and separate and feed the paper while separating the paper. This method can prevent problems caused by mutual adhesion of sheets, but conversely, the rotation timing of the eccentric roller and the rotation timing of separation roller 1' do not match, resulting in a significant difference in the load acting on the sheets separated by separation roller 1'. , the disadvantage of being unable to feed frequently occurs. In other words, when the laminated paper rises, the load when separating and feeding it with the separation roller 1' is small, but when the laminated paper lies down, the load increases, so the load acting on the paper is significantly different, and this depends on the paper size and weight. However, if the stacking amount increases or decreases, the load acting on the sheets to be separated varies greatly, making it impossible to create uniform separation conditions.

In view of the above-mentioned drawbacks, the present invention is capable of reliably separating and feeding stacked sheets of paper even when they are in close contact with each other, and also prevents the paper from being separated and fed due to the difference between the timing of handling the paper and the timing of separation by the separation roller. The main objective is to provide a paper feeding device that eliminates the disadvantages and allows reliable separation and feeding at all times.

The configuration will be described in detail below based on one embodiment shown in the drawings.

Reference numeral 2 denotes an ordinary paper mounting table, and the one shown has a curved shape at the center.

This paper loading table 2 is provided with a separation means indicated by the general symbol A at its tip, a feed roller 3 at the center approximately, and an eccentric roller 4 at the rear end connected to a drive system (not shown). It is provided as follows. In particular, the eccentric roller 4 is arranged to undulate the rear end of the stacked paper 1 on the paper table 2, and by repeating this, the paper is separated.

Various structures can be adopted as the separating means A, such as a separating roller 5 rotating in the paper feeding direction, a reversing roller that presses against the separating roller 5, a fixed roller, and a friction pad. It is composed of

7 is a feed roller, and S is a paper detection sensor.

Therefore, in the present invention, the eccentric roller 4 is in a raised position with respect to the paper table 2 at the beginning of rotation of the separation roller 5.
In other words, the paper 1 is placed in an upright position.

This will be explained with reference to the operational diagrams of FIGS. 3 to 5. First, the eccentric roller 4 is rotated in the state shown in FIG. 3 in response to a paper feed instruction signal from a copying machine, printing machine, or other main unit.

Then, the laminated paper 1 gradually stands up, and even if it faces the reversing roller 6 with its leading edge uneven as shown in FIG. 3B, it comes into contact with the reversing roller 6 in a preferable state as shown in FIG. 4B.

From the rotation of the eccentric roller 4, the feed roller 3, separation roller 5, and reversing roller 6 are started to rotate through an electric delay circuit.

This timing is selected to be at a time immediately after the time when the eccentric roller 4 reaches the raised position (the position in FIG. 4) with respect to the paper mounting table 2.

Then, the leading edge of the paper is separated and bitten between the separation roller 5 and the reversing roller 6 in a proper posture as shown in FIG.

At this time, the entire stack of paper is in the upright position and its own weight is directed toward the separation roller 5, and especially the bottom layer of paper leaves the paper stack 2 except for the leading edge, so the friction of the paper stack 2 is less influential and the paper is separated with less resistance. It is pulled out by rollers 5. When the leading edge of the paper is sent out from the separation roller 5 and reaches the feeding roller 7, a detection sensor S
detects this and stops the eccentric roller 4 and feeding roller 3 (state shown in FIG. 5).

At this time, the trailing edge of the separated and fed paper is arranged to be removed from the feed roller 3 position.

In the state shown in FIG. 5, there is little risk that the lowest layer of paper will come into contact with the paper tray 2 and be drawn into the separation roller 5 due to the friction.

When the trailing edge of the paper leaves the separation roller 5, the separation roller 5 is stopped and the state shown in FIG. 3 is restored to prepare for the next paper feeding.

In the above explanation, the eccentric roller 4 is first rotated in response to the paper feed instruction signal, and then the feed roller 3 and the separation roller 5 are rotated. Feeding roller 3,
The separation roller 5 may be rotated simultaneously with the paper feed instruction signal.

In response to the paper feed instruction signal, the paper on the paper table is raised and separated, and at the same time, the kicked paper can be reliably separated toward the separation roller.

Furthermore, since the eccentric roller is stopped in a lowered position when the paper is separated and reaches the feed roller, there is less risk that the eccentric roller will protrude significantly from the paper table and deform the paper.

Furthermore, the eccentric roller is less likely to become an obstacle when setting paper on the paper table.

[Brief explanation of the drawing]

1A and 1B are explanatory diagrams of a conventional device, FIG. 2 is an overall explanatory diagram of an embodiment of the present invention, and FIGS. 3 to 5 A and B are explanatory diagrams of the operating state. 1...Sheet paper, 2...Paper mounting table, 3...Feeding roller, 4...Eccentric roller, 5...Separation roller.

Claims (1)

[Scope of Utility Model Registration Claim] A paper loading table for stacking and storing paper; a pair of upper and lower separation rollers provided at the leading edge of the paper loading table in the feeding direction; In the paper feed device, the paper feeding device includes a feeding roller provided on the paper loading table for feeding out the paper loading table, and a feeding roller installed in front of the paper loading table in the feeding direction to take over and convey the paper from the separation roller. An eccentric roller is provided at the rear side of the feeding roller of the stand, and the positions in contact with the stacked paper are at different heights, and this eccentric roller is rotated from the downward position to the upward position in response to a paper feed instruction signal, and a sensor at the position of the above-mentioned feeding roller A paper feeding device characterized in that the eccentric roller is stopped in a descending position by a paper leading edge detection signal from a paper feeder.