JPS6056743A - Automatic sheet feeder - Google Patents

Abstract

PURPOSE:To reliably feed a sheet in an automatic sheet feeder of a facsimile or the like by detecting a failure in feeding a document independent of inclination of a document table and applying advancing force to the document by means of an auxiliary sheet feed roller. CONSTITUTION:An auxiliary sheet feed roller 7 always kept apart from the upper surface of a document 2 is disposed on this side of a sheet feed roller 3. When detectors 21, 22, 24 disposed on a document path 23 detects that the leading end of a document 2 to be fed out is not positioned at a designated place at the time of feeding, the auxiliary sheet feed roller 7 is brought into pressure contact with the upper surface of the document 2 until the leading end of the document 2 reaches the detecting position. At this time, driving force is applied to a separation roller 4, so that the uppermost document 2 is fed out to the document path 23 by action of the rollers 3, 4. Although the detector 24 detects the trailing end of the document, if the subsequent document is not detected by the detector 22, a solenoid 12 is energized so that the advancing force is applied to the subsequent document 2 by the roller 7.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a roller separation type automatic paper feeding device for facsimile machines and the like.

Structure of the conventional example and its problems As shown in Fig. 1, the conventional automatic paper feeder of the above type rotates the stacked originals 2 on the inclined original platen 1 in the direction of the arrow with a high-friction member on the outer periphery. The outer periphery of the paper feed roller 3 is made of a friction member lower than that of the paper feed roller 3. If there are two or more documents between the paper feed roller 3 and the paper feed roller 3, the document is moved in the direction of arrow B, and if there is one document or less, the document is moved in the opposite direction. A separation roller 4 provided with a means for rotating the document 5 separates the documents 2 from the uppermost surface one by one and sends them out. In order for the document 2 to be fed without support, 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, by tilting the document table 1, a forward force is applied to the leading edge of the document so as to push it into the contact portion 5 between the paper feed roller 3 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. In addition, with this method that relies on inclination, the forwarding force 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. Therefore, there is a problem in that the leading end is not inserted into the contact portion 5, and therefore, the paper may not be fed.

Purpose of the Invention The present invention has been made to solve the above-mentioned problems, and an object thereof is to provide an automatic paper feeder that does not cause paper feeding failures regardless of the inclination of the document table and regardless of the number of loaded documents. 0 Structure of the Invention The present invention provides a paper feed auxiliary roller which is always maintained at a position away from the top surface of the document in front of the paper feed roller 3, and when feeding the paper,
A detector installed in the document path detects that the leading edge of the document to be fed is not at the specified position, and a paper feed assist roller is pressed against the top surface of the document until the leading edge reaches the detection position to assist in paper feeding. The above object is achieved by applying a forward force to the document by the rotation of the roller and the frictional force of the outer periphery.

DESCRIPTION OF THE EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. Figure 2 shows a schematic configuration of an automatic paper feeder according to an embodiment of the present invention, and Figure 3 shows the configuration of some of the main parts. It shows.

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 at a position approximately in the center in the width direction of the document. The one-way clutch 6 enables the paper feed roller 3 to overrun with respect to the shaft 5. 04 is a separation roller made of a rubber material with a friction coefficient smaller than that of the paper feed roller 3, and applies appropriate pressure to the paper feed roller white. It is in contact with The separation roller 4 is rotated clockwise by a means not shown when two or more originals 2 are present between it and the paper feed roller 3.
If it is less than one sheet, the contact pressure with the paper feed roller 3 causes it to rotate in the opposite direction as the paper feed roller 3 rotates. Reference numeral 7 denotes a paper feed auxiliary roller whose outer periphery is made of a high-friction rubber material, and is fixed to a shaft 9 rotatably attached to a bracket 8. The bracket 8 is rotatably supported by the shaft 5 and has a clockwise rotational force using the shaft 6 as a fulcrum due to its own weight including the paper feed auxiliary roller 7, shaft 9, etc., but the claw portion 8a
is engaged with the pin 13 of the solenoid 12 which is pushed in the direction of the arrow 11 by the spring 10, and a counterclockwise force is applied, and the solenoid 8b is abutted against the bracket 14 for fixing the solenoid 12, so that it is in the position shown in the figure. will be maintained.

Numeral 15 is a toothed belt, which is stretched around the boot IJ 16.17 and transmits the rotation of the shaft 5 to the shaft 9. The speed ratio of the boots IJ 16 and 17 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, and 20 is a pinch roller, which gives 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 drive source, and the peripheral speed of the paper feed roller 3 is the same as that of the paper feed roller 19.
It is smaller than the circumferential speed of 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. The document 2 is placed on the document table 1 so that the leading edge contacts the paper feed roller 3 and the separation roller 4. place The document feed command causes the paper feed roller 3, paper feed auxiliary roller 7, and paper feed roller 19 to rotate, and at the same time, the solenoid 12 is energized and the pin 13
' and release the lock from the claw part 8a, so the bracket
-8 rotates clockwise around the shaft 6, so that the paper feed auxiliary roller 7 falls onto the top surface of the document 2, giving a forward force to the topmost document 2. At this time, a driving force is also applied to the separation roller 4. The document 2 is placed between the paper feed roller 3 and the separation roller 6 to 4.
The topmost sheet is sent to the document path 23 by the action of
2 is i-position, 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 the end of the preceding document 2 is detected by the detector 24.
The speed difference is set such that the leading edge of the next document 2 reaches the detector 22 when passing through. 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 forward force to the next original 2 to eliminate paper feeding failure.

Effects of the Invention According to the present invention, a document feeding failure is detected and a forwarding force is applied to the V document by the paper feeding auxiliary roller, so that paper feeding is performed reliably and the need for tilting the document table is avoided. This has the effect of making it possible to create a configuration without any delay.

[Brief explanation of the drawing]

FIG. 1 is a side view of main parts of a conventional automatic paper feeder, FIG. 2 is a side view of main parts of an automatic paper feeder according to an embodiment of the present invention, and FIG.
The figure 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...Brakeno l-11
2...Solenoid, 21.22°24...
··Detector. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 Figure 3

Claims (1)

[Claims] A paper feed auxiliary roller is provided which rotates in the same direction as the paper feed roller and together with the paper feed roller while the paper feed roller is rotating, and which is normally maintained at a position apart from the document, so that the leading edge of the document to be fed is set as required. means for pressing the paper feed auxiliary roller against the upper surface of the document to be fed by its own weight at a point where the leading edge of the document reaches a predetermined detection position when the document is not in a predetermined position at the time of An automatic paper feeder characterized by: