JPH0423745A - Paper feeding device - Google Patents

Abstract

PURPOSE:To prevent lap feeding with high separating force by locating high friction members and low friction members regularly and mutually in the surface of one or both of a self-feeding roller and a separating roller. CONSTITUTION:High friction members 29 are buried in the surface of a separating roller 13 with a regular pattern to form a mutually located pattern against low friction member of the side where the high friction members are buried. Consequently, the minus side friction force to be caused by the revolution of the separating roller 13 works against the feeding direction of documents 12 to be carried by a self-feeding roller 14 intermittently to generate oscillation, and high separating force can be obtained to prevent lap feeding securely.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to paper feeding devices in printers, facsimile machines, and the like.

[Background of the Invention] A conventional paper feeding device includes a separation roller 13 and a self-feeding roller 14, as shown in FIG. 9, for example.

The separation performance was determined by the ratio of the friction coefficient μ of the separation roller 13 and the self-supplying roller 14.

When the friction coefficient μ2 of the paper 12' to be separated is the friction coefficient μm of the self-supplying roller 14 with respect to the paper 12', and the friction coefficient μ3 of the separation roller 13 with respect to the paper 12', the respective friction coefficients μm, μ2. Separation roller 13, self-supplying roller 14 so that μ3 satisfies the condition of μ2 × μ3 × μl
had decided.

[Problems to be Solved by the Invention] Even with a paper feeding device that satisfies the above-mentioned conditions, if, for example, paper fibers come out from the cut surface of the paper and become entangled with the surface of the separation roller, exceeding the friction coefficient of the separation roller, , paper could not be separated, often resulting in double feeding.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention provides a paper feeding device that includes a self-feeding roller that rotates in a paper feeding direction and a separation roller that rotates in a counter-feeding direction. The present invention is characterized in that high friction members and low friction members are alternately and substantially regularly arranged on one or both surfaces of the separation roller.

[Effect] 21st example showing the first implementation example! In I, document stacker 1
1. The originals 12 stacked on the paper guide 28 are separated by the counterclockwise rotation of the self-feeding roller 14 and the low-speed counterclockwise rotation of the separation roller 13, and only the lowest original 12 is sent to the optical reading system. It will be done.

At this time, the separation roller 13 separates the original 12 due to the strong frictional force intermittently exerted by the high friction member 29 embedded in the surface thereof.

If there are a plurality of sheets of paper between the separating roller 13 and the self-feeding a-roller 14, the vibrations caused by intermittent friction remove the entanglement of fibers adhering to the cut ends of the upper sheets of paper. Further, the lowest document 12 is separated.

The image of the separated original 12 is read by an optical reading unit (optical reading unit) 18, and then it is delivered to the outside of the machine through a paper ejection port 19 by a pressure roller 15, a feed roller 16, and a paper ejection roller 17, which rotate clockwise. The paper is sent to the paper tray.

[Embodiment] Next, an example of the paper feed H position according to the present invention, which is incorporated into a facsimile machine, will be described in detail with reference to the drawings.

FIG. 1 is a schematic diagram of a facsimile machine F incorporating a paper feeding device according to the present invention.

In FIG. 1, the facsimile machine F is comprised of a box-type exterior case 1, a transmitting means 2 for reading original images with an optical reading system, a receiving means 3 for printing and recording incoming image information, and the like. There is.

The exterior case 1 includes a lower cover 4 that serves as a housing, a back cover 6 that houses the reception tray 5, site covers 7 and 7 on both sides (only one is shown), and a transmission door that has an operation panel 8 on the top surface. It consists of a cover 9 and a reception door 10 arranged on the rear side of the top surface.

The operation panel 8 disposed on the inclined upper surface of the exterior case 1 has an LCD board (not shown) of a liquid crystal display unit and a panel assembly (not shown) of pushbutton switches such as a numeric keypad as usual.

The transmitting means 2 includes a document stacker 11 mounted on the upper part of the upper surface of the outer case 1, a separating roller 13 that separates the bi-leaf documents 12 one by one, a self-feeding roller 14 that sends the separated documents 12 to an optical system, and It consists of a pressure roller 15, a feed roller 16, a paper ejection roller 17, and an optical reading unit 18 disposed below the self-feeding roller 14, which are arranged opposite to each other across the surface on which the document 12 moves. The bi-leaf original 12 is separated one by one, the image is read by an optical reading unit 18, and the image is sent out to a paper discharge port 19.

The image signal read by the optical reading unit 18 is transmitted to the other party using a communication line.

The receiving means 3 includes a recording paper storage chamber 21 that stores a roll of recording paper 20 in a manner that it can be freely fed out, and a thermal head that prints and records image information transmitted to the recording paper 20 that is fed out from the recording paper storage chamber 21. 22 and a platen 23,
It is composed of a cutter unit 24 that cuts the recording paper 20 on which the received information is printed and recorded into a predetermined length. It is sent out from the exit 25 onto the receiving tray 5.

FIG. 2 is a schematic diagram of the transmitting means 2 in the facsimile machine F. As shown in FIG.

In FIG. 2, the separation roller 13 is connected to the transmission door 26.
It is rotatably supported on a shaft and rotates counterclockwise at low speed using a transmission motor (not shown) as a drive source. High friction members 29 are embedded in the surface of this separation roller 13 in a regular pattern.

The high friction member 29 has a high H'! relative to the embedded side (separation roller 13: low friction member)! This is the part II.

Therefore, the surface of the separation roller 13 has a pattern in which high-friction areas and low-friction areas are alternately arranged.

Further, the self-supplying roller 14 is rotatably supported by a frame member (not shown) of the exterior case 1, and rotates counterclockwise using the transmission motor as a drive source.

28 is a paper guide that is an extension of the document stacker 11.

The originals 12 on the original stacker 11 and on the paper guide 2 are fed to the optical reading system from the lowest sheet by counterclockwise rotation of the self-feeding roller 14.

At this time, the document 12 in contact with the separation roller 13 is pulled back to the document stacker 119N by the separation roller 13, which rotates counterclockwise at a low speed. High friction members 29 are regularly embedded in the surface of this separation roller 13.

Roughly speaking, when two or more originals 12 are stacked, the friction between the originals 12 and 12 prevents the progress.
No paper is fed to the optical reading system.

The original 12 whose image has been read by the optical reading unit 18 is sent out of the machine from the paper ejection port 19 by the pressing roller 15, the feed roller 16, and the paper ejection roller 17, which rotate clockwise.

3 and 4 show the separating roller 13 (self-supplying roller 1
FIG. 4 is a perspective view showing an arrangement pattern of high friction members 29 in the same example.

In the separation roller 13 shown in FIG. 3, high friction members 29 are embedded in parallel lines.

Furthermore, the separation roller 13 shown in FIG.
9 are buried in a grid pattern.

A parallel line-shaped high friction member 29 and a fourth
In any case of the lattice-shaped high friction members 29 shown in the figure, the surfaces that come into contact with the original (paper) 12 are alternately continuous high friction members 29 and low friction members (the material surface of the separation roller 13).

FIG. 5 is a surface configuration diagram of an embedded separation roller 13 in which a high friction member 29 is embedded in the separation roller 13.

The separation roller 13 shown in FIG. 5 has a high friction member 29 embedded in a spur gear-shaped groove 13a.

FIG. 6 is a surface configuration diagram of the brush-type separation roller 130.

The separation roller 13 shown in FIG.
A brush 30 is installed on the surface as a high-friction member, and this brush 30 increases the friction coefficient and improves separation performance.

71st! I is an enlarged cross-sectional view of a paper separating section consisting of a separating roller 13 and a self-feeding roller 14.

In FIG. 7, high friction members 29 are regularly embedded in the surfaces of the separation roller 13 and the self-supplying roller 14. Note that the high friction member 29 is on the same surface as the surface of other members (separation roller 13, self-supplying roller 14).

Then, by rotating the separating roller 13 and the self-feeding roller 14 counterclockwise, the overlapping documents 12 are reliably separated one by one.

At this time, the document 12 sandwiched between the separating roller 13 and the self-feeding roller 14 is intermittently subjected to a high separating force and vibrates.

FIG. 8 is a curve diagram showing the separation force acting in the feeding direction when a high friction member is provided on each surface of the separation roller 13 and the self-supplying roller 14 shown in FIG. 7.

In FIG. 8, the separation roller 13 exerts a frictional force (minus side) intermittently (wave-like) in the feeding direction of the document 12. As shown in FIG.

Further, the self-supplying roller 14 exerts a frictional force intermittently (wave-like) in the feeding direction (positive side) of the original 12.

In addition, the high friction member 2 of the separation roller 13 and the self-supplying roller 14
When the phases of 9.29 and the low friction members on the other surfaces match, the separation force becomes maximum.

[Effects of the Invention] As described above, the paper feeding device according to the present invention has high friction members and low friction members arranged substantially regularly on the surface of one or both of the self-feeding roller and the separation roller.

By alternately arranging the high-friction members and the low-friction members, a high separation force accompanied by intermittent vibration can be obtained to reliably separate the paper. Therefore, smooth paper feeding can be performed continuously without double feeding.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a facsimile machine incorporating a paper feeding device according to the present invention, FIG. 2 is a schematic diagram of a transmitting means in the facsimile machine, and FIGS. 3 and 4 are arrangement patterns of separation rollers. Each perspective view, No. 6
The figure is a surface configuration diagram of an embedded type separation roller, FIG. 6 is a surface configuration diagram of a brush type separation roller, FIG. 7 is an enlarged sectional view of a paper separation section, and FIG. 81! 1 is a curve diagram showing the separation force exerted by the separation roller and the self-feeding roller in the paper feeding direction, and FIG. 9 is a configuration diagram of a conventional example. ] 3...Facsimile machine...Transmission means...Document...Separation roller...Self-supplied roller...High friction member Fig. 13 Separation roller Fig. 13, All high pressure ports 13 Separation port No. Figure Figure Figure Figure

Claims (1)

[Claims] (1) In a paper feeding device equipped with a self-feeding roller that rotates in the paper feeding direction and a separation roller that rotates in the counter-feeding direction, a high-friction member and a low-friction member are provided on the surface of one or both of the self-feeding roller and the separation roller. A paper feeding device characterized in that the following are arranged alternately in a substantially regular manner.