JPH10114440A - Automatic paper feeding mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an automatic paper feeling mechanism which can prevent an occurrence of wrinkles or a tear in a thin, wood-free paper sheet or inferior paper sheets, which are caused by the deformation of a paper feeding roller or a separation roller. SOLUTION: A highly slidable sheet 1 having the shape of a letter T is installed in a gradually coming-in roller frame 15 and fixed by a check plate 18. The sheet 1 is installed in such a manner that the vertical part of the letter T projects toward the paper feeding or separating roller side and moreover the tip end part of the said vertical part is situated in the vicinity of the central part in the direction of the width of the paper feeding roller and the paper separating roller.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic paper feeding mechanism, and more particularly to a mechanism for automatically feeding paper sheets in a facsimile machine, a copying machine, a printer, and the like.

[0002]

2. Description of the Related Art Conventionally, in an automatic paper feeding mechanism, paper sheets are fed into a transport path by a loading roller from a loading table on which sheets such as originals and copy sheets are loaded. The sheet is sequentially separated one by one by a roller and a separation roller, and is automatically fed.

That is, the above-mentioned automatic paper feed mechanism is shown in FIGS.
As shown in FIG. 7, a loading table 6 on which sheets 21 such as originals to be fed are loaded, a set guide 7 for suppressing skew of the sheets 21, and sheets loaded on the loading table 6 Roller 2 and Roller Shaft 14 for feeding the paper 21 to the paper feeding unit
A paper feed roller 3 and a paper feed roller shaft 13 for transporting the paper sheet 21 fed by the feeding roller 2;
Separation roller 4 for separating sheets one by one from the top one by one
Roller frame 1 that supports the roller 2
5, a clutch mechanism 26 provided with a pin 19 for raising and lowering the feeding roller 2, a tension coil spring 22 for pulling up the feeding roller 2, an electromagnetic clutch 28, an abutment plate 17, and a separation roller 4 Roller frame 16 that supports the separation roller 4, a tension coil spring 23 that presses the separation roller 4 against the feed roller 3, and a separation roller frame support shaft 20.
And a clutch mechanism 27 for controlling the rotation torque of the separation roller 4.

[0004] The moving roller raising / lowering mechanism for raising / lowering the moving roller 2 includes the above moving roller frame 1.
5, a clutch mechanism 26, a tension coil spring 22,
The electromagnetic clutch 28, the paper feed roller shaft 13, the abutment plate 17, and a paper sheet transport detection sensor (not shown).

The paper feed mechanism for sequentially feeding the paper sheets 21 one by one includes the above-described paper feed roller 3, separation roller 4,
A separation roller frame 16, a tension coil spring 22,
It comprises a separation roller frame support shaft 20 and a clutch mechanism 27. An automatic sheet feeding mechanism of a facsimile machine that sequentially separates and feeds the sheets 21 stacked on the stacking table 6 one by one from the above by the feeding roller elevating mechanism and the sheet feeding mechanism. The automatic paper feeding mechanism further includes a discharge conveyance roller 8, an optical unit 9, a pinch roller 10, a conveyance belt 11, a belt roller 12, and the like.

Here, the lowering operation of the feeding roller 2 of the automatic paper feeding mechanism is shown in FIG. 8A, and the feeding operation of the paper sheets 21 and the separating operation of the paper sheets 21 are shown in FIG. 8 (c) shows the raising operation of the feeding roller 2. As shown in FIG. These FIG.
The operation of the automatic paper feed mechanism will be described with reference to FIG.

A driving force from a drive motor (not shown) is transmitted to the paper feed roller shaft 13 by a transmission means (not shown), and the drive motor rotates and the electromagnetic clutch 2 rotates.
8 rotates by being connected.

At the same time as the feed roller shaft 13 rotates, the one-way clutch (not shown) built in the feed roller 3 rotates the feed roller 3. At this time, the rotation drive is transmitted from the paper feed roller 3 to the feeding roller 2 via the gear 29, and the feeding roller 2 rotates.

The rotation of the feed roller shaft 13 causes the clutch mechanism 26 provided at one end of the feeding roller frame 15 to rotate, and the pins 19 provided on the clutch mechanism 26 move to the loading table 6 side. , And the feeding roller frame 15 descends. A projection 30 is provided on a part of the clutch mechanism 26. When the pin 19 of the clutch mechanism 26 moves until the feeding roller 2 reaches the lowermost position of the lowermost point, the projection 30 is moved to the abutment plate 17. And the movement of the pin 19 stops.

The driving force of the drive motor is also transmitted to the reverse transport roller 5 and the discharge transport roller 8, and the reverse transport roller 5 and the discharge transport roller 8 rotate simultaneously with the rotation of the paper feed roller shaft 13. Driving force is transmitted to the separation roller 4 from the reverse conveyance roller 5 by a transmission unit (not shown).

A driving force is transmitted to the separation roller 4 so as to rotate in a direction opposite to the rotation direction of the sheet feeding roller 3.
However, the rotation of the separation roller 4 itself is controlled by the clutch mechanism 27, and the separation roller 4 rotates or stops in the same direction as the paper feed roller 3 due to a change in the frictional resistance between the separation roller 4 and the paper feed roller 3, Or reverse. The frictional resistance between the separation roller 4 and the paper feed roller 3 differs depending on whether the paper 21 is not interposed or when a plurality of papers 21 are fed. When feeding occurs, the separation roller 4 rotates in the reverse direction and feeds extra paper sheets 21 back to the loading table 6.

When the feeding roller frame 15 is lowered, the feeding roller 2 comes into pressure contact with the topmost sheet 21 of the sheets 21 stacked on the loading table 6 to feed the sheets. Send it to the paper feed unit. The sheets 21 sent to the sheet feeding section are successively sent one by one to the reverse transport roller 5 by the operation of the separation roller 4.

The paper sheet 21 sent to the reverse transport roller 5
Is transported by the reverse transport roller 5. When the paper sheet 21 is conveyed by the reverse conveyance roller 5, the document presence sensor 31 detects the leading end of the paper sheet 21, whereby the electromagnetic clutch 28 is disconnected and the rotation of the paper feed roller shaft 13 is stopped.

When the rotation of the feed roller shaft 13 stops, the pin 19 returns to the standby position by the tensile force of the tension coil spring 22 hooked on the pin 19 of the clutch mechanism 26. When the pin 19 is going to return to the standby position, the pin 19 is hooked on the feeding roller frame 15 on the way and lifts the feeding roller frame 15.

When the rotation of the paper feed roller shaft 13 is stopped, the paper sheet 21 is transported by the reverse transport roller 5 and the discharge transport roller 8. When the sheet 21 is conveyed and the document presence / absence sensor 31 detects the trailing end of the sheet 21, the electromagnetic clutch 28 is connected again to restart the sheet feeding.
The start and end of the sheet feeding operation are controlled by the document presence sensor 3.
1 and a switch (not shown) provided on an operation panel (not shown).

[0016]

In the above-mentioned conventional automatic paper feeding mechanism, the paper sheets stacked on the loading table are sequentially separated and fed one by one by a separation roller. The separation performance is determined by the applied load and the setting of the idling torque of the torque limiter. In this case, in order to increase the separation performance, it is necessary to set the idling torque of the torque limiter to a large value. Since the idling torque of the torque limiter is one of the sources of the pressing force pressing the separation roller, increasing the idling torque necessarily increases the pressing force of the separation roller.

In the automatic paper feed mechanism, unless rollers having the lowest possible hardness are used for the paper feed roller and the separation roller,
Separation performance cannot be ensured. Therefore, when the pressing force of the separation roller is increased, each of the sheet feeding roller and the separation roller is deformed.

When the paper feed roller and the separation roller are deformed, the degree of the deformation is different between the both ends and the center where the pressing is likely to be applied. When the degree of deformation is different, the braking force on the paper sheet is increased at the center of the roller, and the transport force on the paper sheet is increased at both ends of the roller.

Thick paper such as copy recording paper is not affected by this, but in the case of thin high-quality paper or miscellaneous paper, an obstacle such that the paper is turned up and broken at the center of the roller occurs, and Jamming may occur. In that case, the thinner the paper sheet, the more likely it is that an obstacle will occur, causing wrinkles and blurring.

Therefore, an object of the present invention is to solve the above-mentioned problems and to prevent the occurrence of wrinkles and blurring on thin high-quality paper or miscellaneous paper due to deformation of the feed roller and the separation roller. It is to provide a paper mechanism.

[0021]

According to the present invention, there is provided an automatic paper feed mechanism comprising: a loading table for loading paper sheets; a feeding roller for feeding the paper sheets loaded on the loading table to a transport path; A paper feed roller for transporting the paper sheets fed by the feeding roller, and the paper sheets provided so as to face the paper feed roller and transported one by one by the paper feed roller. An automatic sheet feeding mechanism including a separating roller for sequentially separating sheets one by one, comprising a sheet member fixedly disposed between the sheet feeding roller and the separating roller and having a small friction coefficient.

As described above, according to the present invention, a high-slidable sheet having a small coefficient of friction is provided between the paper feed roller and the separation roller near the center of the roller, so that the paper feed roller and the separation roller can be separated. , Especially near the center of the roller. This makes it possible to prevent wrinkles and blurring on thin high-quality paper or miscellaneous paper due to deformation of the feed roller and the separation roller.

[0023]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view of one embodiment of the present invention, and FIG. 2 is a partially enlarged cross-sectional view of a feeding roller elevating mechanism and a paper feeding mechanism according to one embodiment of the present invention. In these figures, one embodiment of the present invention shows an example in which the present invention is applied to a facsimile apparatus like the conventional example shown in FIGS.

That is, the automatic sheet feeding mechanism according to one embodiment of the present invention includes a loading table 6 for loading sheets 21 such as originals to be fed, a set guide 7 for suppressing skew of the sheets 21,
The feeding roller 2 and the feeding roller shaft 14 for feeding the paper sheets 21 loaded on the loading table 6 and feeding them to the paper feeding unit, and a feeding roller for feeding the paper sheets 21 fed by the feeding roller 2. A paper roller 3 and a paper supply roller shaft 13; a separation roller 4 for sequentially separating the paper sheets 21 one by one from above; a feeding roller frame 15 for supporting the feeding roller 2; 2, a butting plate 17, a separation roller frame 16 that supports the separation roller 4, a tension coil spring 23 that presses the separation roller 4 against the feed roller 3, and a separation roller frame support shaft 20.
In addition, a discharge / conveying roller 8, an optical unit 9, a pinch roller 10, a conveying belt 11, a belt roller 12, the same clutch mechanisms 26 and 27 as the conventional example, an electromagnetic clutch 28, and the like are provided.

The lifting roller raising / lowering mechanism for performing the raising / lowering operation of the lifting roller 2 is similar to the conventional example, and includes the above-described lifting roller frame 15, clutch mechanism 26, tension coil spring 22, electromagnetic clutch 28, , A paper feed roller shaft 13, an abutment plate 17, and a sheet transport detection sensor (not shown).

The paper feed mechanism for sequentially feeding the paper sheets 21 one by one also has the same structure as the conventional example.
A separation roller 4, a separation roller frame 16, a tension coil spring 22, a separation roller frame support shaft 20,
And a clutch mechanism 27. An automatic sheet feeding mechanism of a facsimile machine that sequentially separates and feeds the sheets 21 stacked on the stacking table 6 one by one from the above by the feeding roller elevating mechanism and the sheet feeding mechanism.

Further, the automatic sheet feeding mechanism according to one embodiment of the present invention reduces the separation force generated between the sheet feeding roller 3 and the separation roller 4, particularly, the separation force near the center of the roller. Stop plate 18 on the roller frame 15
The high slidable sheet 1 fixed by the above is disposed between the paper feed roller 3 and the separation roller 4 in the vicinity of the central portion in the width direction of the rollers. The high slidability sheet 1 is formed of a member having a small coefficient of friction (for example, a polymer polyethylene sheet or the like).

FIG. 3 is a view showing a structure for mounting the highly slidable sheet 1 of FIG. In the figure, a T-shaped highly slidable sheet 1 is attached to a feeding roller frame 15 and fixed by a stopper plate 18. In this case, the T-shaped high slidable sheet 1 has a T-shaped vertical bar portion protruding toward the feed roller 3 and the separation roller 4, and a tip portion of the T-shaped vertical bar portion has a feed roller 3. Also, it is attached so as to be located near the center portion of the separation roller 4 in the width direction.

As described above, since the high slidability sheet 1 is formed of a member having a small coefficient of friction, the separation force generated near the central portion between the sheet feeding roller 3 and the separation roller 4 is suppressed, The separation force near the center of these rollers is reduced. Therefore, wrinkles and blurring of thin high-quality paper and miscellaneous paper due to deformation of the paper feed roller and the separation roller are prevented by the highly slidable sheet 1.

Further, even when the paper sheet 21 is not interposed between the paper feed roller 3 and the separation roller 4, the high slidability sheet 1
Is fixed to the feeding roller frame 15 by the stopper plate 18, so that it does not get caught by the paper feed roller 3 or the separation roller 4.

FIG. 4A is a view showing the lowering operation of the feeding roller 2 of FIG. 1, and FIG. 4B is a drawing of the paper sheet 21 and the paper sheet 21 according to an embodiment of the present invention. FIG. 4C is a diagram showing the raising operation of the feeding roller 2 of FIG. The operation of the automatic sheet feeding mechanism according to the embodiment of the present invention will be described with reference to FIGS. Since the operation is the same as that of the conventional example except that the sheet 21 is sequentially fed one by one by the feed roller 3 and the separation roller 4, the detailed description is omitted.

A driving force is transmitted to the separation roller 4 so that the separation roller 4 rotates in a direction opposite to the rotation direction of the sheet feeding roller 3.
Due to a change in the frictional resistance between the separation roller 4 and the paper feed roller 3, the paper feed roller 3 rotates, stops, or reverses in the same direction. The frictional resistance between the separation roller 4 and the paper feed roller 3 differs depending on whether the paper 21 is not interposed or when a plurality of papers 21 are fed. When feeding occurs, the separation roller 4 rotates in the reverse direction and feeds extra paper sheets 21 back to the loading table 6.

In this case, if the pressing force of the separation roller 4 is increased, the paper feed roller 3 and the separation roller 4 are each deformed, and even if the braking force against the paper sheet 21 is increased at the central portion of these rollers, Since the highly slidable sheet 1 is disposed between the paper feed roller 3 and the separation roller 4, especially near the center in the width direction of the rollers, the highly slidable sheet 1 is provided.
As a result, the braking force against the paper sheet 21 at the central portion of the rollers is reduced.

Therefore, even when the paper sheet 21 is a thin high-quality paper or miscellaneous paper, it is possible to prevent the obstacle that the paper is turned up and broken at the central portion of the rollers, and the occurrence of jamming, Alternatively, occurrence of wrinkles and blur can be prevented.

As described above, the highly slidable sheet 1 having a small coefficient of friction is attached to the roller frame 15 and the stop plate 1
8 and is disposed between the paper feed roller 3 and the separation roller 4, particularly in the vicinity of the center of the paper feed roller 3 and the separation roller 4 in the width direction. The generation of wrinkles and blurring on thin high-quality paper or miscellaneous paper due to deformation of the paper can be prevented.

[0036]

As described above, according to the present invention, a loading table for loading paper sheets, a feeding roller for feeding the paper sheets loaded on the loading table into a transport path, and a feeding roller are provided. A paper feed roller for conveying the fed paper sheets, and a separation roller provided opposite to the paper feed roller and separating paper sheets one by one so that the paper sheets are conveyed one by one by the paper feed roller. In the automatic paper feed mechanism including the above, by disposing a sheet member having a small coefficient of friction between the paper feed roller and the separation roller in a fixed manner, thin high quality paper due to deformation of each of the paper feed roller and the separation roller, This has the effect of preventing wrinkles and blurring of miscellaneous paper and the like.

[Brief description of the drawings]

FIG. 1 is a sectional view of one embodiment of the present invention.

FIG. 2 is a partially enlarged cross-sectional view of a feeding roller elevating mechanism and a paper feeding mechanism according to an embodiment of the present invention.

FIG. 3 is a view showing a mounting structure of the highly slidable sheet of FIG. 1;

4A is a diagram illustrating a lowering operation of a feeding roller of FIG. 1, FIG. 4B is a diagram illustrating a feeding operation and a separating operation of a paper sheet according to an embodiment of the present invention, and FIG. FIG. 3C is a diagram illustrating a raising operation of the feeding roller of FIG. 1.

FIG. 5 is a sectional view of a conventional example.

FIG. 6 is a partially enlarged cross-sectional view of a feeding roller elevating mechanism and a paper feeding mechanism according to a conventional example.

FIG. 7 is a perspective view of a conventional example.

8A is a diagram showing a lowering operation of the feeding roller of FIG. 5, FIG. 8B is a diagram showing a conventional operation of feeding and separating paper sheets, and FIG. FIG. 9 is a diagram illustrating a raising operation of a feeding roller of No. 5;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 High slidable sheet 2 Roll-in roller 3 Feeding roller 4 Separation roller 6 Loading table 15 Roll-in roller frame 18 Stop plate 21 Paper sheets

Claims (3)

[Claims] 1. A loading table for loading paper sheets, a feeding roller for feeding the paper sheets loaded on the loading table into a conveying path, and the paper sheets fed by the feeding roller. And a separation roller provided opposite to the paper feed roller and sequentially separating the paper sheets one by one so as to be conveyed one by one by the paper feed roller. An automatic paper feed mechanism, comprising a sheet member fixedly disposed between the paper feed roller and the separation roller and having a small friction coefficient. 2. The automatic sheet feeding mechanism according to claim 1, wherein the sheet member is disposed at a central portion in a width direction of each of the sheet feeding roller and the separation roller. 3. The automatic sheet feeding mechanism according to claim 1, further comprising a fixing member for fixing the sheet member so as to be disposed between the sheet feeding roller and the separation roller.