JPH061473A - Document separator - Google Patents

Abstract

PURPOSE:To prevent overlapped feeding and non feeding even when there are a plural number of originals. CONSTITUTION:A plural number of originals are set by inserting them between a carrier auxiliary roller 3 and a frictional member 1. The set originals A are pressed by a pressure plate 6 through a pressure spring 7. After it starts carrying the originals A, the originals A hit a straight part 8 of the frictional member 1 and only a few lower sheets of a plural number of the originals A enter between the carrier roller 2 and a pressure contact part 1a of the frictional member 1, and consequently, the documents A are not fed overlapped.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a document separating device, and more particularly to a document separating device which prevents double feeding and non-feeding of a plurality of documents in a facsimile.

[0002]

2. Description of the Related Art A conventional facsimile apparatus, copying machine, or the like is provided with an automatic sheet feeding device for sequentially feeding laminated sheets such as originals from the lowest sheet. Set multiple sheets of laminated paper on the paper feed table so that they are inserted between the feeding roller and the friction piece. When the set paper rotates the roller in the predetermined direction by the drive source, the friction between the rollers causes the rollers to move. A force acts to feed the paper along the circumference. Then, the laminated sheets are sorted by the friction piece whose tip portion is brought into pressure contact with the roller by the pressure of the pressing plate so that the stacked sheets can be sequentially fed out from the lowest sheet. However, when the preceding paper is thick, there is a disadvantage that the widening gap of the friction piece is large, the succeeding paper enters deeply into the large gap at the same time, and the succeeding paper is not separated but superposed.

In order to solve this point, for example, an "automatic sheet feeder" is proposed in Japanese Utility Model Publication No. 61-24512. In this publication, the leading end of the friction piece is pushed open by the thick preceding paper, but the central portion of the friction piece is pressed by the pressure adjusting screw and curved, so the gap narrows due to this curved portion. That is, it is possible to prevent the sheets from deeply entering at the same time. However, in the method described in the above publication, an error may occur due to the user's setting method (for example, strong thrusting) on thick paper or due to changes in the environment (for example, 35 °, 85% high temperature and high humidity). The rate increased and the reliability was insufficient.

4 (a) and 4 (b) are views showing a conventional document separating device. FIG. 4 (a) is a state in which a document is set, and FIG.
Shows the conveyance states of the originals. In the figure, 21 is a friction member, 22 is a conveyance roller, 23 is a conveyance auxiliary roller, 24
Is a pressing spring, 25 is a conveyance guide, 26 is a pressure plate,
27 is a pressure spring. When there are multiple originals, the leading edge of the original is uneven, or the uppermost surface of the leading edge of the original protrudes the most, and it is in the so-called reverse wedge state where it is on the stairs.
There are many double feeds and non-feeds. For example, the document A set with a reverse wedge pushes up the friction member 21 immediately after the conveyance is started, and a plurality of documents are simultaneously inserted between the conveyance roller 22 and the friction member 21. As a result, the initial pressure contact force of the friction member 21 decreases, the originals cannot be separated, and a problem such as double feeding occurs. Further, if the pressure contact force is increased to prevent this, the frictional force of the pressure contact portion increases too much, and conversely, there is a problem such as non-feeding. The double feed occurs because the weight of the original increases and the inertial force also increases when the number of originals is large, so that the double feed occurs because the paper is vigorously entered between the conveyance roller 22 and the friction member 21 immediately after the start of conveyance. However, it becomes more remarkable as the number of documents increases. However, the above-mentioned problem hardly occurs when the number of original documents is about 2 to 5. This is because the inertial force is small and the friction member 21 is squeezed by the friction member 21 even if it rushes into the pressure contact portion, and normal separation is possible.

[0005]

An object of the present invention is to provide a document separating device which prevents double feeding and non-feeding even when there are a plurality of documents, in view of the above-mentioned circumstances. It was made as.

[0006]

In order to achieve the above object, the present invention provides (1)
In a document separating device including a conveying roller for separating a plurality of stacked documents one by one, and a friction member that is in pressure contact with the conveying roller, the conveying roller and the friction member are slightly separated from the pressure contact surface. Further, a straight portion is provided on the friction member perpendicularly to the conveying surface in the conveying upstream direction, and further, (2) the straight portion is made of a material having a small friction coefficient, and further, (3) above (1) ),
The height from the lower part of the straight section to the transport surface is several sheets of the original to be used, and further, (4) (1) to
The configuration of (3) is applied to a facsimile machine. Hereinafter, description will be given based on examples of the present invention.

FIG. 1 is a block diagram for explaining an embodiment of a document separating apparatus according to the present invention, in which 1 is a friction member,
Reference numeral 1a is a pressure contact portion of a friction member, 2 is a conveyance roller, 3 is a conveyance auxiliary roller, 4 is a pressing spring, 5 is a conveyance guide, 6 is a pressure plate, 7 is a pressure spring, and 8 is a straight portion. A plurality of originals are set so as to be inserted between the conveyance assisting roller 3 and the friction member 1. Original A set
Are pressed by the pressure plate 6 via the pressure spring 7. After the conveyance is started, the originals collide with the straight portion 8 of the friction member 1, and only the lower several sheets of the plurality of originals enter between the conveyance roller 2 and the pressure contact portion 1a of the friction member, so that they may be double-fed. Absent. That is, even when a large number of originals are set in the reverse wedge state, after the start of the original conveyance, the upper original hits the straight portion 8 and only the lower several originals are conveyed to the pressure contact portion.

Since a force is applied to the straight portion 8 substantially at right angles to the moving direction of the friction member 1, a large load can be supported, and the pressure contact portion 1a of the friction member 1 is loaded with only a few originals. Obviously, the number of sheets is apparently separated, and naturally, the separation performance is as high as the reliability of the small number set.

FIG. 2 is a view showing the structure of the friction member in FIG. 1, and the reference numerals in the drawing are the same as those in FIG. When the friction member is plate-shaped, for example, the main body of the friction member 1 is made of a member having a small friction coefficient such as polyacetal, and the pressure contact portion 1 is used.
The member a has a high friction coefficient such as rubber.

3 (a) and 3 (b) are views showing another structure of the friction member in FIG. 1, FIG. 3 (a) is a plan view, and FIG. 3 (b) is a perspective view. In the figure, 9 is a non-rotating roller (polyacetal) having a straight portion, 10 is a friction member roller (rubber), and other parts having the same functions as those in FIG. When the friction member is in the form of a roller, it is preferable to use a member having a small friction coefficient, such as polyacetal, so that the straight portions 8 slightly project from both ends of the roller 10.

[0011]

As is apparent from the above description, the present invention has the following effects. (1) In the document separating apparatus provided with the friction member having the straight portion, the straight portion receives the load that tries to lift the friction member upward due to the rush of the document immediately after the start of conveyance, and the pressure contact force of the friction member is received. It is stable and only a few lower originals are projected into the press contact portion, and even when a large number of sheets are set, apparently the same performance as when a small number of sheets is set can be obtained. (2) By forming the straight portion with a member having a small coefficient of friction, the original abutting on the straight portion can be smoothly slid downward when being fed out from below. (3) By making the lower part of the straight part a little distance from the conveying surface, it is possible to limit the number of originals that enter the press contact part, and the same performance as separating a small number of originals can be obtained. (4) A facsimile machine having the effects described in (1) to (3) above can be obtained.

[Brief description of drawings]

FIG. 1 is a configuration diagram for explaining an embodiment of a document separating device according to the present invention.

FIG. 2 is a configuration diagram of a friction member in FIG.

FIG. 3 is another configuration diagram of the friction member in FIG.

FIG. 4 is a configuration diagram of a conventional document separating device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Friction member, 1a ... Pressure contact part of friction member, 2 ... Conveying roller, 3 ... Conveying auxiliary roller, 4 ... Pressing spring, 5 ... Conveying guide, 6 ... Pressure plate, 7 ... Pressure spring, 8 ... Straight part.

Claims (2)

[Claims] 1. A document separating device comprising a conveying roller for separating a plurality of stacked originals one by one, and a friction member in pressure contact with the conveying roller, wherein the conveying roller and the friction member are in pressure contact with each other. A document separating device, characterized in that a straight portion is provided on the friction member perpendicularly to the conveying surface in the conveying upstream direction slightly separated from the surface. 2. The document separating apparatus according to claim 1, wherein the straight portion is made of a material having a small friction coefficient.