JPH04197928A - Paper feeding device - Google Patents

Abstract

PURPOSE:To perform the make-up feed of numerous sheets smoothly into a specified position without bringing the uppermost sheet into contact with a paper feed roller by covering the paper feeding direction upstream side of the paper feed roller lower part with a cover member at the time of lowering a hopper in the direction of being separated from the paper feed roller. CONSTITUTION:When a hopper 12 is pushed down at the time of refilling sheets, a separating claw 25 descends together with the hopper 12. At this time, a cover member 28 positioned on the upstream side of the paper feeding direction of a paper feed roller 16 is lowered into a specified position, so that the paper feeding direction upstream side in the lower part of the paper feed roller 16 is covered with this cover member 28. A large number of sheets are then inserted in the paper feeding direction so as to be positioned in a gap between the paper feed roller 16 and the hopper 12. At this time, the uppermost sheet is guided by the cover member 28 in such a way as not to come in contact with the paper feed roller 16, and thus the sheets are make-up fed into the specified position.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a paper feeding device used in a copying machine, a printer, etc., either integrally or detachably installed. The present invention relates to a paper feeding device having an automatic paper feeding mechanism (auto sheet feeder mechanism).

(Prior Art) An image forming apparatus such as a copying machine or a printer is provided with a paper feeding device to supply paper to a developing section or a printing section. FIG. 4 shows an example of a paper feeding device having an automatic paper feeding mechanism. The paper feeding device is built into a thermal printer, which is an image forming device, and its automatic paper feeding mechanism 7o has a flat hopper 72 on which a large number of sheets of paper 8o are placed. The side opposite to the paper feeding side is rotatably supported by a shaft portion 72a, and the hopper 7
The paper feed side side portion of No. 2 is rotatable in the vertical direction.

Then, the paper feeding side side of the hopper 72 is pressed against the push spring 7.
5, it is urged upward.

Separation claws 74 are provided at each side edge in the width direction of the hopper 72 in the paper feeding direction. Each separation claw 74 is engaged with each corner of the paper feed side side of the paper 80 placed on the hopper 72 .

A paper feed roller 76 made of rubber is disposed on the side of the hopper 72 on the paper feed side. The uppermost paper 80 placed on the hopper 72 is pressed against the paper feed roller 76 by the biasing force of the push spring 75 . Then, by rotating the paper feed roller 76 in a predetermined direction,
Only the paper 80 pressed against the paper feed roller 76 passes over each separation claw 74 and is fed.

Paper fed by the automatic paper feeding mechanism 70 is fed to the print section 60 of the thermal printer. The print section 6
0 has a paper guide 61 that guides the paper fed by the automatic paper feed mechanism 70, and a feed roller 62 that feeds the paper fed along the paper guide 61 in a predetermined direction. . The paper guide 61 has a side portion on the paper feeding direction side shaped like an arc along the circumferential surface of the feed roller 62 . The paper guide 61 is provided with a pair of pinch rollers 63 and 64 that respectively pinch the paper to be conveyed together with the peripheral surface of the feed roller 62.

The paper is conveyed along the paper guide 6e, and the feed roller 6
2 and pinch rollers 63 and 64, the paper is transferred to the platen 6 by the feed roller 62.
5 and an ink ribbon 6 moved by a carriage 66.
7, and an image is printed on the paper.

The manual paper feed tray 77 is arranged above the automatic paper feed mechanism 70, and the paper 32 placed on the manual feed tray 77 is sequentially fed to the feed roller 62 of the print section 60. be done.

FIG. 5 shows a paper feeding device that can be attached to and detached from the print section 60. As shown in FIG. The automatic paper feeding mechanism of the paper feeding device has the same structure as the paper feeding mechanism 70 of the paper feeding device shown in FIG. 4, and similar members are given like numbers and explanations will be omitted. The paper feeding device includes a paper ejection tray 78 on which the paper on which a predetermined image has been printed by the print section 60 is placed, and a paper ejection roller that guides the paper ejected from the print section 60 onto the paper ejection tray 78. 79.

(Problem to be Solved by the Invention) In any paper feeding device, when placing a large number of sheets on the hopper 72, the spring 7 pushes the hopper 72.
The hopper 72 is pushed down against the urging force of the hopper 72.
A gap is formed between the paper feed roller 76 and the paper feeding roller 76, and a large number of sheets of paper are inserted into the gap from the upstream side in the paper feeding direction. The paper feed roller 76 is usually made of a material with a high coefficient of friction, such as rubber, in order to reliably feed the paper. Therefore, when a large number of sheets of paper are inserted into the gap between the paper feed roller 76 and the hopper 72, the uppermost paper to be inserted comes into contact with the paper feed roller 76, and the uppermost paper is The paper feeding roller 76 prevents the paper from moving in the paper feeding direction, and there is a risk that the uppermost paper may be misaligned with the other papers.

Furthermore, the paper feeding device shown in FIG. 4 has a disadvantage in that the manual paper feeding section has a separate structure from the automatic paper feeding section, which increases the size of the device. On the other hand, in the paper feeding device shown in FIG. 5, the paper is manually fed between the paper feeding roller and the hopper, which eliminates the disadvantage of increasing the size of the device. However, since the paper feed roller 76 is made of a material with a high coefficient of friction, there is a possibility that the manually fed paper will come into contact with the paper feed roller 76 and that the paper will not be fed smoothly.

The present invention solves these problems, and its purpose is to reduce the resistance during paper feeding due to paper contacting the paper feed roller when replenishing paper onto a hopper or when manually feeding paper. The object of the present invention is to provide a paper feeding device that can perform the following tasks.

(Means for Solving the Problems) A paper feeding device of the present invention has a large number of sheets of paper placed thereon, and is supported so that the side portion on the paper feeding side can rotate in the vertical direction. A flat hopper whose side portions are biased upward; and a side portion of the hopper that faces the paper feed side.
A paper feed roller that feeds the paper by rolling contact with the paper on the hopper; and a paper feed roller that engages with a corner of the paper on the paper feed direction side of the paper on the hopper, and moves to a predetermined position as the hopper descends. A separating claw is disposed upstream of the paper feeding roller in the paper feeding direction, and as the separating claw descends, it covers the lower part of the paper feeding roller on the upstream side in the paper feeding direction, and also covers the upstream side of the paper feeding roller in the paper feeding direction. A cover member is provided that opens the lower upstream portion of the paper feed roller in the paper feeding direction when the paper feed roller is raised by a predetermined amount or more, thereby achieving the above object.

(Function) In the paper feeding device of the present invention, when the hopper is pushed down during paper replenishment, the separation claw moves down together with the hopper. At this time, both the separation claw and the cover member located upstream of the paper feed roller in the paper feed direction are lowered to a predetermined position, and the cover member covers the lower part of the paper feed roller on the upstream side in the paper feed direction. Then, a large number of sheets of paper are inserted in the paper feeding direction so as to be positioned within the gap between the paper feeding roller and the hopper. At this time, the uppermost paper is guided by the cover member so as not to come into contact with the paper feed roller, and the paper is replenished at a predetermined position.

When paper replenishment is completed and normal paper feeding operation is performed, the paper on the hopper moves upwards in the hopper and becomes engaged with the separation claw, and the separation claw engages with the paper. When the cover member is rotated upward, the cover member also moves upward, and the upstream side in the paper feeding direction at the bottom of the paper feeding roller is opened, and the uppermost paper comes into contact with the paper feeding roller.

(Example) Examples of the present invention will be described below.

As shown in FIG. 1, the paper feeding device of the present invention is, for example, integrally attached to a thermal printer. The paper feeding device 10 has a flat hopper 12 disposed on the side of the inclined bottom surface 11 of the housing 13 in the paper feeding direction. The hopper 12 has a shaft portion 12a on the side opposite to the paper feed side so that the side on the paper feed side moves in the vertical direction.
(see FIG. 3), it is rotatably supported by the housing 13. The paper feeding side side of the hopper 12 is urged upward by a push spring 15 interposed between the hopper 12 and the housing 13. On the hopper 12, the paper feeding side side of the paper that is placed on the bottom surface ll of the housing 13 is placed.

As shown in FIG. 2, guide plates 22 are provided on each side of the hopper 12 in the width direction.

Each guide plate 22 is vertically provided on the side edge of the hopper 12 so as to be slidable in a direction perpendicular to the paper feeding direction. A hopper 12 is installed on the side wall of the housing 13.
A paper feed roller 16 is attached to a supporting shaft (not shown) that is rotatably supported and facing above.

A base end portion of an arm portion 24 is rotatably supported on the outer surface of the side of the guide plate 22 opposite to the paper feeding side.

The arm portion 24 extends from the paper feed side side portion of the guide plate 22, and the hopper 12 is attached to the tip end of the arm portion 24.
Separation claws 25 are provided along the side edges of the housing and project inwardly. The separating claw 25 is in a state along the side edge of the paper feeding side of the hopper 12, and the side part on the hopper 12 side has a tapered shape whose thickness gradually decreases in the direction opposite to the paper feeding direction. It stands out. Then, the separating claw 25 is connected to the hopper 1.
It is in a state where it is locked to the paper feeding side edge of No. 2. A support portion 26 extends downward from the side portion of the separation claw 25 on the paper feeding side. The downward movement of the support portion 26 is stopped by a stopper 29 erected on the bottom surface ll of the housing 13.

A cover member 2 is provided on the upstream side of the paper feed roller 16 in the paper feeding direction.
8 are arranged. The cover member 28 is opposed to the paper feed roller 16 on the upstream side of the paper feed roller 16 in the paper feed direction, in an inclined state that approaches the paper feed roller 16 as it goes downward. A connecting portion 28 a extending beyond the upper portion of the guide plate 22 to the outside of the guide plate 22 is provided at the upper portion of the cover member 28 .
A is connected to the upper side of the support plate 28b disposed along the outer surface of the guide plate 22 on the upstream side in the paper feeding direction. The support plate 28b is attached on the arm portion 24. Therefore, as the tip of the arm portion 24 rotates in the vertical direction, the entire cover member 28 moves in the vertical direction. By moving the cover member 28 downward, the lower end of the cover member 28 is positioned closer to the hopper 12 than the lower end of the paper feed roller 16, and the lower end of the paper feed roller 16 is located on the upstream side in the paper feeding direction. It becomes covered.

A printing section 60 is arranged on the paper feeding direction side of the hopper 12. The print section 60 includes a paper guide 61 extending along the paper feeding direction of the hopper 12 and a feed roller 62 located on the side of the paper guide 61 in the paper feeding direction. The feed roller 62 has a plurality of roller parts, as shown in FIG. The paper guide 61 is continuous with a portion of the stopper 29 of the paper feeding device 10 that extends in the paper feeding direction. The side portion of the paper guide 61 in the paper feeding direction has an arc shape along the circumferential surface of the feed roller 62. A pair of pinch rollers 63 and 64 are disposed within the paper guide 61 so as to face the circumferential surface of the feed roller 62, respectively. And feed roller 6
A platen 65 is disposed on the paper feeding direction side of No. 2,
An ink ribbon (not shown) is disposed opposite the platen 65, as in the prior art example described above.

The operation of the paper feeding device having such a configuration will be explained.

In the paper feeding device in the state shown in FIG. 1, no paper is placed on the hopper 12. In such a situation,
Manual paper feeding is performed. At this time, the side of the hopper 12 on the paper feeding side rises due to the spring force of the push spring 15, and as the hopper 12 rises, the separation claw 25 locked to the hopper 12 rises, and the separation claw The arm portion 24 to which 25 is connected is rotated upward. As a result, the cover member 28 integrally supported by the arm portion 24 also rises, and the lower end of the cover member 28 is positioned slightly above the lower end of the paper feed roller 16. And in such a state,
The hopper 12 is rotated downward and brought into contact with the stopper 29.

As a result, the cover member 28 moves downward, and the lower end of the cover member 28 is positioned below the lower end of the paper feed roller I6. As a result, the paper feed roller 16 is completely covered by the cover member 28. Then, by manually feeding the sheets one by one along the hopper 12, the sheets pass over the separating claws 25 and are placed in the print section 60, similar to the conventional sheet feeding device shown in FIG.
The paper is fed to the feed roller 62 at.

When replenishing paper onto the hopper 12, the hopper 12 is pushed down. As a result, the separation claw 25 that is engaged with the side edge of the paper feed side of the hopper 12 also rotates downward together with the hopper 12, but the separation claw 25 is rotated downward by a predetermined amount. It comes into contact with the stopper 29 and is stopped. In this state, the cover member 28 is stopped while covering the lower end of the paper feed roller 16. From this state, as shown in FIG. 3, the hopper 12 is further pushed down, and a large number of stacked sheets are placed on the hopper 12.

At this time, since the paper feed roller 16 is covered by the cover member 28, the uppermost sheet of paper placed on the hopper 12 comes into contact with the paper feed roller 16 and is misaligned with other sheets. There is no risk of becoming Since the cover member 28 is stopped while covering the lower part of the paper feed roller 16, the paper is also smoothly placed on the hopper 12.

In this way, when a large number of sheets of paper are placed on the hopper 12, the hopper 12 is moved upward by the push spring 15, and each separation claw 25 is engaged with the uppermost paper, and the separation claw 25 is rotated upward. As a result, the cover member 28 is also rotated upward, and the uppermost sheet comes into contact with the paper feed roller 16. By rotating the paper feed roller 16 in this state, the uppermost paper is fed to the feed roller 62 of the print section 60 over the separation claw 25.

(Effects of the Invention) As described above, in the paper feeding device of the present invention, when the hopper is lowered in the direction away from the paper feeding roller in order to replenish paper, the cover member is located at the bottom of the paper feeding roller. In order to cover the upstream side in the paper feeding direction, 1. The uppermost sheet of a large number of sheets to be replenished is smoothly replenished to a predetermined position without contacting the paper feed roller. As a result, there is no risk that the paper will be misaligned. In addition, even when manually feeding paper, the cover member covers the lower part of the paper feed roller on the upstream side of the paper feed direction, so when manually feeding paper to a predetermined position, the paper does not reach the paper feed roller. There is no risk of contact. When feeding paper, the cover member moves upward to open the lower part of the paper feed roller, so the paper does not form a circle. Paper is fed to lt.

4. Facts B Fig. 1 is a schematic configuration diagram showing an example of the paper feeding device of the present invention, Fig. 2 is a perspective view of its main parts, Fig. 3 is an explanatory diagram of its operation, and Fig. 4 is a diagram showing a conventional paper feeding device. FIG. 5 is a schematic configuration diagram showing an example of a paper feeding device. FIG. 5 is a schematic configuration diagram showing another example of a conventional paper feeding device.

12...Hopper, 16...Paper feed roller, 22...
...Guide plate, 24...Arm part, 25...Separation claw, 26...Support part, 27...Slit, 28...
cover member.

that's all

Claims (1)

[Claims] 1. A large number of sheets of paper are placed, and the side part on the paper feed side is supported so as to rotate in the vertical direction, and the side part on the paper feed side is urged upward. A flat hopper, a paper feed roller that is disposed opposite to the paper feed side of the hopper and feeds the paper by rolling contact with the paper on the hopper, and the paper on the hopper. a separation claw that engages with a corner of the side in the paper feeding direction of the hopper and is lowered to a predetermined position as the hopper descends; A cover that covers the upstream side of the lower part of the paper feeding roller in the paper feeding direction as the separating claw descends, and opens the upstream part of the lower part of the paper feeding roller in the paper feeding direction as the hopper rises above a predetermined amount. A paper feeding device comprising: a member;