JPH07215516A - Paper sheet feeding mechanism - Google Patents

Abstract

(57) [Abstract] [Purpose] Paper feeding mechanism for separating paper by a separating member having a sliding surface and a friction surface, and paper feeding for forming a friction surface on a guide plate and pressing it from the side for separating and feeding the accumulated paper. The purpose is to provide a mechanism. [Structure] A sheet accommodating portion 2 accommodating and accumulating sheets 1, a feeding roller 5 for feeding out the sheets 1 from the sheet accommodating portion 2 by rotation, and a front surface of the feeding sheet 1 provided near the front of the feeding roller 5 Paper guide member 10 to
It is provided to face the paper guide member 10 with a predetermined gap, has a sliding surface 11 and a friction surface 12, and rotates in the opposite direction to the feeding direction of the paper 1 guided by the paper guide member 10, A separating member 9 is provided for separating the sheet 1 by the friction surface 12 and passing the sheet 1 by the sliding surface 11 when a plurality of sheets 1 are fed out, and the sheets 1 separated by the separating member 9 are sent out one by one. The configuration.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feeding mechanism such as a printer, and more particularly, to a paper feeding mechanism having a sliding surface and a friction surface on a separating member for separating a fed paper into a plurality of sheets. The present invention relates to a paper feeding mechanism in which a pressing surface of a paper guide member that presses and guides a side surface of a paper has a high friction surface.

Recently, printers such as laser printers and wire dot printers have been used as output devices for personal computers, word processors and the like, and these printers are provided with a paper feeding mechanism for feeding cut sheets to be printed one by one. Has been.

However, when the accumulated sheets are fed out, they may be double-fed, which often causes a sheet jam in the conveying path and causes the apparatus to stop frequently, thus lowering the efficiency of use of the apparatus.

Therefore, as a paper separating method of the paper feeding mechanism, a claw separating method and a friction separating method are used. The claw separation method places claws at the front edge position of the accumulated sheets,
Since the loosened paper is detached from the claws and separated and fed out at the time of feeding, the cost is low, but the both ends of the paper are easily folded or double feed occurs. Further, the friction separation method uses a separation pad, and since the separation pad is rubbed by the feed roller until the paper arrives, the driving load of the feed roller is large.

Therefore, there is a demand for a mechanism which has a small driving load, can be normally separated, and can prevent the both ends of the sheet from being bent.

[0006]

2. Description of the Related Art Hereinafter, conventional examples (1) and (2) of a sheet feeding mechanism for feeding a sheet 1a to a printer will be described.

1) Conventional example (1) The conventional example (1) is a claw separation system, and as shown in the side sectional view of FIG. 9 (a), the paper 1a accommodated in the cassette 2a is pressed vertically swingably. The sheets 3 are stacked on the plate 3, the left end of the pressing plate 3 is biased upward by the spring 4, and the upper surface of the sheet 1a is positioned so as to be fed by the feeding roller 5a arranged above. In addition, feed rollers 8a and 8b that make rolling contact are arranged in front of the cassette 2a and on the left side in the figure.

The feeding roller 5a is formed in a D shape having a circular arc section and a linear section in cross section, and the stepping motor
Connected to M1 (hereinafter referred to as a motor), the motor 1 drives it to rotate and feed the paper 1a at the arc portion. When the straight portion reaches the horizontal position, the rotation stops, and the paper 1 resists the feed roller 5a. Instead, it is delivered by the feed rollers 8a and 8b.

Further, as shown in the plan view of FIG.
Guide plates 6a, 6b that can be moved according to size in the width direction of 1a
Is guided by. Separation claws 7a and 7b located inside both ends of the upper surface of the sheet 1a are provided at the front end position of the cassette 2a in association with the movement of the guide plates 6a and 6b.

With this structure, the sheet 1a delivered by the rotation of the delivery roller 5a in the direction of the arrow is caught by the separating claws 7a and 7b, as shown by the two-dot chain line in the figure.
When the slack is generated in the front part and the slack increases, the top sheet 1a
The tip ends of the sheet are separated from the separation claws 7a, 7b and proceed forward, and are sent out by the feed rollers 8a, 8b.

2) Conventional example (2) The conventional example (2) is a friction separation system, and as shown in the side cross-sectional view of FIG. 10, the feed roller 8a and the feed roller 8a are separated near the front of the cassette 2b. Pat 9a is provided. The contact surface of the separating pad 9a is made of a material having a large friction coefficient, for example,
It is made of cork board.

With this structure, the sheet 1a delivered by the rotation of the delivery roller 5a is transferred to the feed roller 8a.
When the contact point of the separating pad 9a is reached, even if there is a double feed, the friction of the separating pad 9a prevents the progress of the separation and the sheet is separated, and only the uppermost sheet 1a is sent out by the feed roller 8a.

In this way, it is possible to prevent double feeding of the sheet 1a sent from the cassettes 2a and 2b.

[0014]

According to the above-mentioned conventional method, the nail separating method of the conventional example (1) is low in cost because only the separating nail is provided, but after the leading edge of the paper is caught by the separating nail, Since the paper is repelled and loosened due to the looseness of the paper, it is easy for double-feeding or folds at both ends of the paper during separation.

In the friction separation system of the conventional example (2), the feed roller is driven to rub the separation pad with the feed roller until the sheet fed by the feed roller reaches the rolling contact position between the feed roller and the separation pad. The load increases.

Also, in common with the prior art examples (1) and (2), the sheets accumulated and stored in the cassette have a coefficient of friction between the sheets which is to be separated due to changes in environmental conditions such as type of sheet and temperature and humidity. When the value becomes large, the sheets are not accurately separated in the cassette during the feeding operation by the feeding roller, and double feed is likely to occur. For this reason, the contact area of the separating claw to the paper and the contact pressure are optimized to deal with it. This optimization is carried out by the type and environmental conditions of the paper, that is, the rigidity of the paper, the smoothness of the paper surface, and the texture of the paper. It is difficult to take a large margin because the separation conditions are determined in consideration of various parameters such as direction, paper width variation, temperature and humidity, and therefore the margin for paper type and environment is reduced.
It is difficult to obtain sufficient effects. There is a problem.

It is an object of the present invention to provide a sheet feeding mechanism capable of stably separating sheets and preventing double feed from occurring.

[0018]

1 and 2 are principle diagrams of the present invention. FIG. 1 is a principle diagram corresponding to claim 1, and FIG. 2 is a principle diagram corresponding to claim 6.

1) Means corresponding to claim 1 In FIG. 1, 1 is a sheet, 11 is a sliding surface, 12 is a friction surface, 2
Is a paper accommodating section accommodating and accumulating the paper 1 and 5 is a paper accommodating section 2
The feeding roller 10 that feeds the paper 1 from the paper by rotation, 10 is a paper guide member that is provided in front of the paper accommodating portion 2 and guides the upper surface of the paper 1 that is fed by the feeding roller 5, and 9 is a predetermined gap in the paper guide member 10. Are provided opposite to each other, have a sliding surface 11 and a friction surface 12, and rotate in the direction opposite to the feeding direction of the paper 1 guided by the paper guide member 10, so that the friction surface 12 allows the paper 1 It is a separating member that separates the sheet 1 when the sheet is fed out and allows the sheet 1 to pass by the sliding surface 11.

Therefore, the sheet 1 separated by the separating member 9 is sent out one by one. 2) Means corresponding to claim 6 In FIG. 2, 1 is a sheet, 15 is a frictional surface 2 is a sheet accommodating section accommodating and accumulating the sheets 1, 5 is a feeding roller for feeding out the sheets 1 from the sheet accommodating section 2 by rotation, 6 Are a plurality of guide plates that are in contact with each other in the width direction orthogonal to the feeding direction of the accommodated sheets 1, and at least one of the guide plates is a friction surface 15 having a high friction coefficient, and 16 is a guide. Board 6
Is a pressing unit that elastically presses at least one of them on the side surface of the sheet 1.

[0021]

[Action]

1) Operation corresponding to claim 1 Before the sheet 1 is delivered by the delivery roller 5, the separating member 9 rotates in the opposite direction to the feeding direction of the sheet 1, and the friction surface 12 and the sheet guide member 10 face each other. At the position, when the plural sheets 1 are fed by the friction surface 12, the sheets 1
Then, the separating member 9 is further rotated, and the paper 1 is sent out through the gap with the paper guide member 10 by the sliding surface 11, so that the paper 1 can be sent one by one.

Therefore, like the conventional nail separation method,
There is no excessive deformation of the paper 1 and no increase in load due to contact with the separating pad unlike the friction separating method.
It is possible to carry out a stable separation and prevent double feed.

2) Actions Corresponding to Claim 6 At least one of the guide plates 6 contacting both side surfaces of the sheets 1 accumulated and accommodated in the sheet accommodating portion 2 is a friction surface 15, and at least one side surface is pressed by a pressing means. By pressing with the 16, it is possible to apply a stable load to the side edge of the paper 1 in the width direction, and when the paper 1 is fed by the feeding roller 5,
The back tension in the separation direction can be applied to the sheet to increase the drag force of the stacked sheets in the separation direction, and the influence of the variation in the frictional force between the sheets due to the sheet type, the variation in the sheet width, etc. can be reduced, and the sheet 1 can be stabilized. Can be separated and double feed can be prevented.

[0024]

【Example】

1) Description of Embodiment An embodiment of the present invention (corresponding to claim 1, claim 2 and claim 3) will be described with reference to FIGS. 3 is a side view showing an embodiment of the present invention, FIG. 4 is an explanatory view of the embodiment,
FIG. 5 shows a time chart of the embodiment. The same reference numerals denote the same objects throughout the drawings.

The cassette 2b, the separation roller 9b, and the upper guide 10a shown in FIG. 3 correspond to the paper container 2, the separation member 9, and the paper guide member 10 shown in FIG. 1, respectively. As shown in FIG. 3, the separation roller 9b and the upper guide 10a are provided in front of the cassette 2b.
Are opposed to each other through a predetermined gap (a gap through which one sheet of paper can pass).

The separating roller 9b has a cross section having an arc portion and a straight portion, and the arc portion has, for example, a sliding surface 11a obtained by mirror-finishing a metal material, and the straight portion has a material having a high friction coefficient. For example, it has a friction surface 12a to which a plate made of cork is attached.

Further, the separating roller 9b and the gear 91 are fixed to the shaft 90, a fan-shaped gear 92 that meshes with the gear 91 at a predetermined rotation angle is provided, and a gear 94 meshes with a gear 93 coaxial with the fan-shaped gear 92. . The timing belt is attached to the pulley P1 coaxial with the gear 94 and the pulley P2 provided on the shaft 50 of the feeding roller 5a.
(Below belt) 51 is hung.

The shaft 90 is rotatably supported by a device frame (not shown), is urged in the direction of arrow A by a spring 95, and the left end of the friction surface 12a is opposed to the upper guide 10a by a stopper (not shown). Stopped at.

In the normal state, the delivery roller 5a is in a position where the sector gear 92 is not meshed with the gear 91, and the sector roller 92 is set to rotate once when the delivery roller 5a makes one rotation.

Therefore, when the feeding roller 5a is rotated by the drive of the motor M1, the pulleys P1 and P2, the gears 94 and 93, and the fan-shaped gear are
The gear 91 rotates via 92 against the elastic force of the spring 95, and the separating roller 9b rotates in the direction of arrow B accordingly.

With this structure, the operation will be described with reference to FIGS. 4 and 5. When the linear portion of the feeding roller 5a is positioned below and substantially horizontal, the fan gear 92 does not mesh with the gear 91,
The vicinity of the left end of the friction surface 11a of the separation roller 9b is at a position facing the upper guide 10a. This is the normal state, that is, the waiting position for feeding.

Next, at the point (a) in FIG.
Starts to rotate, and at the point (b), the paper 1a is fed out, and by the point (c) at which the leading edge of the paper 1a reaches the position where the separation roller 9b and the upper guide 10a face each other, the double feed is performed on the paper 1a. Even if there is, the lower sheet 1a is separated by the friction with the friction surface 12a. (FIG. 4 (a)) In the above, the leading edge of the sheet 1a is the separation roller 9b and the upper guide 10a.
At the timing (point (c)) when it reached the facing position of
92 engages with the gear 91, the separating roller 9b rotates in the direction of arrow B by a predetermined angle, and the sliding surface 11a faces the upper guide 10a, as shown in FIG. Is pushed by the feeding roller 5a and passes through the gap between the upper guide 10a and the sliding surface 11a.

The sheet 1a is further fed by the feeding roller 5a, and is conveyed by a conveying roller (not shown) provided at a predetermined position in the subsequent stage of the separating roller 9b. At point (e), the feeding roller 5a has a straight line portion substantially downward. Position horizontally and stop.

When the sheet 1a passes through the sliding surface 11a of the separating roller 9b (point (d)), the engagement between the fan-shaped gear 92 and the gear 91 is released, and the separating roller 9b is moved in the direction of arrow A by the elasticity of the spring 95. It rotates and returns to the original position, that is, the position shown in FIG. 4 (a).

2) Description of a different embodiment (1) FIGS. 6 to 8 show a different embodiment (1) (corresponding to claims 4 and 5). 6 and 7 are different from the embodiment described with reference to FIGS. 3 to 5 in that a registration roller and a pinch roller are provided instead of the upper guide to separate the sheet 1a, correct skew, and send out. .

That is, as shown in the side sectional view of FIG. 6 (a) and the plan view of FIG. 6 (b), the registration roller is opposed to the upper side of the separation roller 9b with a predetermined gap. Corresponding) 13 is provided. A sensor S1 that detects the leading edge and the trailing edge of the sheet 1a is arranged near the position where the separation roller 9b and the registration roller 13 face each other.

The registration roller 13 is connected to a stepping motor (hereinafter referred to as a motor) M2 (not shown) and is normally stopped. When the leading edge of the sheet 1a delivered by the delivery roller 5a is detected by the sensor S1. The motor M2 is driven to start rotating in the direction of the arrow, and stops rotating when the trailing edge of the sheet 1a is detected by the sensor S1.

A pinch roller (corresponding to the pressing roller of claim 5) 14 rolls below the registration roller 13. As shown in FIG. 7, the pinch roller 14 is rotatably supported by a support arm 140 fixed to a device frame (not shown).

Having such a structure, the operation will be described below. Paper 1a fed by feeding roller 5a
When the tip collides with the rolling contact position of the registration roller 13 and the pinch roller 14 where the tip is stopped, slack occurs as shown by the chain double-dashed line in FIG. 6 (a), and both ends of the tip in the width direction are in the rolling contact position. The separation roller 9b rotates in the direction of the arrow B at the timing of collision with, and the sensor S1 detects the leading edge of the sheet 1a and the registration roller 13 starts rotating.

Then, the sheet 1a is sandwiched between the registration roller 13 and the pinch roller 14 and is sent out through the sliding surface 11a of the separation roller 9b. If there is a double feed in the feeding by the feeding roller 5a, the separation roller 9b
When the paper 1a fed out is skewed as shown by the chain double-dashed line in FIG. 6 (b), the leading end of the top paper 1a is pinched by the registration roller 13 and pinch roller 13a. When the roller 14 collides with the rolling contact position of the roller 14, the skew is corrected as described above and the sheet is delivered.

Thus, in the above embodiment and the different embodiment (1), the separation surface 9a and the friction surface 12 are attached to the separation roller 9b.
Using a separation roller 9b having a, sliding surface 11a and friction surface
Since the sheet 1a is sent out by the rotation of the sheet 12a, it is possible to prevent the sheet 1a from being unduly deformed, and prevent the both ends of the sheet from being bent or being double-fed at the time of separation as in the conventional nail separation method. Moreover, since the sliding surface 11a is provided,
It is possible to prevent an increase in load due to contact with the separation pad 9a as in the conventional friction separation method.

3) Description of Different Embodiment (2) FIG. 7 shows a different embodiment (2) (corresponding to claim 6). The friction pad 15a and the leaf spring 16a in FIG. 7 correspond to the friction surface 15 and the pressing means 16 in FIG. 2, respectively.

FIG. 7 is different from the embodiment described with reference to FIGS. 3 to 5 or the different embodiment (1) described with reference to FIGS. 6 and 7.
In the paper feed mechanism of the claw separation method, by providing a friction surface on the guide plate of the paper storage unit and pressing it from the side of the paper,
This is to enable stable separation of the sheet 1a.

That is, as shown in FIG. 7, in the claw separation type sheet feeding mechanism, both sides in the width direction of the sheets 1a accumulated and stored in the cassette 2a are sandwiched by the guide plates 6A and 6B.
A friction pad 15a made of a material having a high friction coefficient, for example, cork, is attached to the surface of the guide plate 6A on the sheet 1a side. Also, set a leaf spring on the paper 1a side of the guide plate 6B.
When the guide plate 6B is attached to the side edge of the sheet 1a, the surface 16a of the plate spring 16a presses the guide plate 6B.

With this structure, the guide plates 6A, 6A and
By B, the force in the opposite direction becomes larger than the overlapping friction of the sheets 1a due to the lateral pressure of the leaf spring 16a and the friction of the friction plate 15a on the accumulated sheets 1a, and the uppermost sheet
1a slips and is separated.

That is, in the conventional method, the parameter relating to the separability at this time is the amount of the pressing plate 3 and the separating claws 7a and 7b caught on the leading edge of the sheet, but the sheet 1a by the pressing plate 3 and the feeding roller 5a. By exerting a drag force in the paper separation direction independently of the vertical pressure due to the pressure contact of the paper, the influence of friction between the paper 1a is suppressed, and there are changes in environmental conditions such as paper type, paper width variation, temperature and humidity. However, stable separation can be performed.

In the above embodiment and the different embodiment (1), the case where the friction surface 12a of the separation roller 9b is formed as a flat surface (chord) has been described, but it may be an arc surface, for example, an outer peripheral surface.
Further, although the case where the separating member is the separating roller has been described, it may have another shape, for example, although not shown, a vertically long elliptical shape is formed, and instead of the spring 95, the elliptical lower portion is formed to be heavy. Alternatively, when the fan-shaped gear 92 is disengaged from the gear 91, it may be returned to the normal position by the weight of the lower part.

In the above example, the friction surface 12a and the separating pad
Although the case where the cork is used for the contact surface of 15a has been described, it goes without saying that another high friction material such as a flocked sheet, neoprene or the like may be attached or the surface may be roughened.

In the different embodiment (2), the guide plate
Although the case where the leaf spring 16a is attached to the 6B has been described, the leaf spring may be attached to both the guide plates 6A and 6B, and instead of the leaf spring 16a, at least one of the guide plates 6A and 6B is a pressing member, For example, a method of pressing the side edge of the sheet 1a with a pressing spring or the like may be used. Further, the case where the friction pad 15a is attached to the guide plate 6A has been described.
Friction pads may be attached to both A and 6B.

[0050]

As described above, according to the present invention, in the first, second and third aspects, the sheets are separated and fed one by one by the rotation of the sliding surface and the friction surface of the separating member. As a result, it is possible to perform stable separation of the paper without applying excessive deformation to the paper like the conventional nail separation method, and without increasing the load due to contact with the separation pad like the friction separation method. It is possible to prevent double feed.

According to the present invention, the feed roller is provided so as to face the separating member, and the feed roller is rotated and fed out after the leading end of the paper collides with the stopped feed roller, so that the paper is separated and skewed. Is fixed.

According to the fifth aspect, since the pressing roller which is in rolling contact with the feeding roller according to the fourth aspect is provided, the separated sheet can be stably fed. According to the present invention, the frictional surface of the guide plate and the pressing means apply a stable load to the side edges in the width direction of the paper, thereby giving a back tension in the separation direction to the paper at the time of feeding and stacking paper in the separation direction. It is possible to increase the drag force of the paper and reduce the effect of frictional force fluctuation between papers due to paper type, paper width variation, temperature and humidity, etc., and it is possible to stably separate papers and prevent double feed. it can. There is an effect.

[Brief description of drawings]

FIG. 1 is a principle diagram corresponding to claim 1 of the present invention.

FIG. 2 is a principle diagram corresponding to claim 6 of the present invention.

FIG. 3 is a configuration diagram showing an embodiment of the present invention.

FIG. 4 is an explanatory diagram of an example.

FIG. 5 is a time chart of an example.

FIG. 6 is a configuration diagram showing a different embodiment (1) (No. 1)

FIG. 7 is a configuration diagram (2) showing a different embodiment (1).

FIG. 8 is a configuration diagram showing a different embodiment (2).

FIG. 9 is a configuration diagram showing a conventional example (1).

FIG. 10 is a side sectional view showing a conventional example (2).

[Explanation of symbols]

1,1a is paper, 2,2a, 2b is paper storage,
5,5a are feeding rollers, 6,6a, 6b, 6A, 6B are guide plates,
9 is a separating member, 9a is a separating pad,
9b is a separation roller, 10 is a paper guide member, 10a is an upper guide, 11, 11a are sliding surfaces,
12, 12a and 15 are friction surfaces, 13 is a registration roller, 14 is a pinch roller, 15a is a friction pad, 16 is a pressing means, and 16a is a leaf spring.

Front page continuation (72) Inventor Haruhisa Inagaki 1015 Kamiodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa Fujitsu Limited

Claims (6)

[Claims] 1. A paper accommodating portion (2) accumulating and accommodating paper (1)
And a feeding roller (5) for feeding the sheet (1) from the sheet storage section (2) by rotation, and a sheet provided near the front of the feeding roller (5) and fed by the feeding roller (5). A paper guide member (10) for guiding the upper surface of (1), and a paper guide member (10) provided to face the paper guide member (10) with a predetermined gap, and having a sliding surface (11) and a friction surface (12), The paper (1) is guided by the paper guide member (10) in a direction opposite to the feeding direction of the paper (1), and when the plurality of papers (1) are fed, the paper (1) is fed by the friction surface (12). ) Is separated and the sliding surface (1
A sheet feeding mechanism comprising: a separating member (9) that allows the sheet (1) to pass therethrough according to (1), and sends out the sheets (1) separated by the separating member (9) one by one. 2. The separating member (9) has the friction surface (12) facing the paper guide member (10) in a normal state, and the paper (1) fed by rotation of the feeding roller (3) is When the separating member (9) and the paper guide member (10) reach a position facing each other, rotation is started and the slip surface (11) causes the paper (1) to move.
The sheet feeding mechanism according to claim 1, wherein the sheet feeding mechanism passes the sheet. 3. The separating member (9) rotates to a predetermined position, and the separating member (1) passes through a gap between the paper guide member (10) and the sliding surface (11). 9. The reverse rotation of 9) returns it to its original position.
Alternatively, the paper feeding mechanism according to claim 2. 4. The guide member (10) is the separation member.
It is composed of a feed roller that is in rolling contact with (9) and is rotationally controlled in the feeding direction of the paper (1), and the feed roller is such that the tip of the paper (1) fed by the feeding roller (5) is the separating member. 3. The method according to claim 1, wherein the rotation is started after reaching the rolling contact position with (9), and the rotation is stopped after the rear end of the sheet (1) passes through the rolling contact position. Alternatively, the paper feeding mechanism according to claim 3. 5. The sheet feeding mechanism according to claim 4, wherein the feeding roller is provided with a pressing roller that rolls in contact with the separating member (9) in the same direction. 6. A paper accommodating portion (2) accumulating and accommodating paper (1)
A feeding roller (5) for feeding the sheet (1) from the sheet storage section (2) by rotation, and a roller (5) abutting at least in the width direction orthogonal to the feeding direction of the accommodated sheet (1), A plurality of guide plates (6) having a friction surface (15) having a high friction coefficient as the contact surface with one paper (1), and at least one of the guide plates (6) on the side surface of the paper (1). A paper feeding mechanism comprising a pressing means (16) for elastically pressing.