JPH0121050B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an automatic paper feeding device of a roller separation type in a facsimile machine or the like.

Configuration of conventional example and its problems As shown in FIG.
If there are two or more documents between the paper feed roller 3, which rotates in the direction of arrow A, whose outer periphery is a high-friction member, and the paper feed roller 3, whose outer periphery is a low-friction member, the paper feed roller 3 rotates in the direction of arrow B. separation roller 4 provided with a means to rotate in the opposite direction if there is less than one sheet;
Accordingly, the uppermost original 2 is separated and sent out one by one. In order for the document 2 to be fed without any trouble, a frictional force must be exerted between the paper feed roller 3 and the upper surface of the leading edge of the document when the paper feed roller 3 starts rotating. For this reason, the original platen 1
By tilting the paper feed roller 3 to the leading edge of the document.
A forward force was applied to the contact portion 5 between the separation roller 4 and the separation roller 4. The condition that the document table 1 needs to be tilted becomes a factor that increases the height of the apparatus. Furthermore, in a method that relies on such an inclination, the forwarding force described above may be insufficient especially when the number of sheets stacked is small because the document 2 used does not easily slide on the document table 1 or has a curled edge. However, there was a problem in that the leading end of the paper was not inserted into the contact portion 5, and therefore the paper was not fed.

Purpose of the Invention The present invention solves the above-mentioned problems, and aims to provide an automatic paper feeding device that does not depend on the inclination of the document table, does not depend on the number of loaded documents, and does not cause paper feeding defects. shall be.

Structure of the Invention The present invention provides a paper feed auxiliary roller that is always maintained at a position away from the top surface of the document in front of the paper feed roller 3, so that the leading edge of the document to be fed is at a predetermined position during paper feeding. A detector installed in the document path detects this, and the paper feed auxiliary roller is pressed against the top surface of the document until the tip reaches the detection position, and the document is moved forward by the rotation of the paper feed auxiliary roller and the frictional force on the outer periphery. The aim is to achieve the above objective by providing the following.

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

FIG. 2 shows a schematic configuration of an automatic paper feeder according to an embodiment of the present invention, and FIG. 3 shows the configuration of some essential parts. In the figure, 1 is a document table, 2 is a document, and 3 is a paper feed roller whose outer periphery is made of a high-friction rubber material, which is attached to a shaft 5 via a one-way clutch 6 at a position approximately in the center in the width direction of the document.
The one-way clutch 6 connects the paper feed roller 3 to the shaft 5.
allows for overruns. Reference numeral 4 denotes a separating roller made of a rubber material having a coefficient of friction smaller than that of the paper feed roller 3, and is in contact with the paper feed roller 3 with an appropriate pressure. The separation roller 4 is separated by means not shown.
If there are two or more documents 2 between the paper feed roller 3 and the paper feed roller 3, the document rotates clockwise, and if there is one document or less, the document 2 rotates in the opposite direction due to the contact pressure with the paper feed roller 3. It is designed to rotate in the direction.
Reference numeral 7 denotes a paper feeding auxiliary roller whose outer periphery is made of high-friction rubber material, and a shaft 9 rotatably attached to a bracket 8.
It is fixed in. The bracket 8 is rotatably supported by the shaft 5, and is connected to the paper feed auxiliary roller 7 and the shaft 9.
The solenoid 1 has a clockwise rotational force about the shaft 5 as a fulcrum due to its own weight, but the claw portion 8a is pushed in the direction of the arrow 11 by the spring 10.
2, a counterclockwise force is applied to the solenoid, and the surface 8b abuts against the bracket 14 for fixing the solenoid 12, so that the solenoid 12 is maintained in the illustrated position.

A toothed belt 15 is stretched around pulleys 16 and 17 and transmits the rotation of the shaft 5 to the shaft 9. Pulley 16,1
The speed ratio 7 is set so that the peripheral speed of the paper feed auxiliary roller 7 is slightly slower than the peripheral speed of the paper feed roller 3. A one-way clutch 18 is interposed between the pulley 17 and the shaft 9 to enable the paper feed auxiliary roller 7 to overrun. 19 is a paper feed roller, 20
is a pinch roller that applies a sub-scanning speed to the document 2 fed by the paper feed roller 3. The paper feed roller 19 and the paper feed roller 3 are driven by the same driving source, and the circumferential speed of the paper feed roller 3 is smaller than the circumferential speed of the paper feed roller 19. The detector 21 detects the presence or absence of the document 2 on the document table 1, the detector 22 detects the passage of the leading edge of the document 2 in the document path 23, and the detector 24 detects the passage of the trailing edge. When the detector 21 detects that a document is present and the detector 22 does not detect the document 2, the solenoid 12 is energized. Reference numeral 25 denotes a guide member that corrects the curvature in the width direction of the document 2 placed on the document table 1, and is movable according to the width of the document.

Next, the operation will be explained.

The document 2 is placed on the document table 1 so that its leading edge contacts the paper feed roller 3 and separation roller 4 . Paper feed roller 3, paper feed auxiliary roller 7,
The paper feed roller 19 rotates, and at the same time the solenoid 12
energized, the pin 13 moves to 13', and the claw part 8a
Since the bracket 8 is released from the lock, the bracket 8 rotates clockwise about the shaft 5, and the paper feed auxiliary roller 7 falls onto the upper surface of the document 2, applying forward force to the uppermost document 2. At this time, a driving force is also applied to the separation roller 4, and the uppermost sheet of the original 2 is transferred to the original path by the action of the paper feed roller 3 and the separation roller 4.
Sent out on 3rd.

This signal from the leading edge of the document passing through the detector 22 deenergizes the solenoid 12, and the paper feed auxiliary roller 7 returns to its original position. Next, the document 2 comes under the force of the feed roller 19, and the detector 24 detects that the document 2 has passed the end.

The paper feed speed by the paper feed roller 3 and the paper feed speed by the paper feed roller 19 are such that when the end of the preceding document 2 passes the detector 24, the leading edge of the next document 2 has reached the detector 22. The speed difference is set as follows. Therefore, if the detector 24 detects the end but the next document 2 is not detected by the detector 22, this is a case where the paper feeding failure described in the conventional example has occurred, and the solenoid 12 is energized,
The paper feeding auxiliary roller 7 applies a forward force to the next original 2 to eliminate paper feeding failure.

Effects of the Invention According to the present invention, a feeding failure of the original is detected and a forwarding force is applied to the original by the paper feeding auxiliary roller, so that the feeding of the original is performed reliably and the need for tilting the original table is determined. This has the effect that it can be configured without any problems.

[Brief explanation of drawings]

FIG. 1 is a side view of a main part of a conventional automatic paper feeder, FIG. 2 is a side view of a main part of an automatic paper feeder according to an embodiment of the present invention, and FIG. 3 is a plan view of the main part. 1...Original table, 2...Original, 3...Paper feed roller, 4...Separation roller, 7...Paper feed auxiliary roller,
8... Bracket, 12... Solenoid, 21,
22, 24...detector.

Claims (1)

[Claims] 1. A document table on which multiple sheets of originals are stacked, a paper feed roller that feeds out the documents on this document table one by one, and a paper feed roller that rotates in the same direction while the paper feed rollers are rotating. a paper feed auxiliary roller maintained at a position apart from the document in the direction; a first detector for detecting the leading edge of the document provided in the feeding direction of the paper feed roller; Furthermore, a second detector is provided on the downstream side to detect the end of the document, and when the feeding of the document starts, the paper feed auxiliary roller falls onto the top surface of the document on the document table and reaches the end. A forward force is applied to the document on the upper side to feed it, and when the first detector detects the leading edge of the document, the paper feed auxiliary roller is returned to its original position, and then the second detector detects the leading edge of the document. If the end of the document is detected, and the first detector does not detect the leading edge of the next document even though the second detector detects the end of this document, it is determined to be a paper feed failure. An automatic paper feeder that drops the paper feed auxiliary roller onto the top surface of the document again to apply forward force to the document.