JPH0571496B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Technical Field> The present invention relates to a paper feeding device for feeding sheet-like copy paper.

<Prior Art> In a copying machine such as an electrostatic copying machine, it is necessary to sequentially feed copy paper through a predetermined copy paper transport path defined within the copy machine housing.
In recent years, paper feeding devices have been put into practical use in which a copy paper cassette containing sheet copy paper cut to a predetermined size is removably attached to a cassette receiver provided in a copying machine housing. . In such a paper feeding device, the copy paper cassette includes a cassette main body having an opening formed in the bottom wall and a mounting plate rotatably attached to the cassette main body, and the stacked sheets of copy paper are placed on the mounting plate. It will be placed. On the other hand, the cassette receiver includes a pressure contact mechanism that acts on the loading plate through an opening formed in the cassette body, and a pressure mechanism that acts on the uppermost sheet of copy paper stored in the cassette body to send it out. A feeding mechanism is provided.

Examples of such a paper feeding device include those disclosed in Japanese Utility Model Publication No. 54-9741 and Japanese Patent Application Laid-open No. 58-104840, or Japanese Patent Application Laid-Open No. 59-57838. can be raised.

In the paper feeding device disclosed in Japanese Utility Model Publication No. 54-9741 and Japanese Patent Application Laid-Open No. 58-104840, the pressure contact mechanism has a pressure contact lever that is elastically biased and acts on the mounting plate, and also has a pressure contact lever that is elastically biased and acts on the mounting plate. The feeding mechanism includes a plurality of feeding rollers arranged at intervals in the lateral direction, and is configured such that the pressure lever acts on the lateral center of the mounting plate.

On the other hand, in recent years, there has been a strong demand for copying onto relatively small paper such as government postcards.
In the case of a type in which various types of copy paper are fed with the center of the copy paper cassette as a reference, the feeding roller must be disposed above the lateral center of the loading plate.

However, in the above-mentioned conventional paper feeding device, when feeding relatively small size paper, the feeding roller located in the center only acts on the paper to be copied, and no inconvenience occurs. When feeding relatively large copy paper, both ends of the loading plate tend to curve downward due to the weight of the copy paper itself, and due to manufacturing errors. Due to these factors, the pressing force between the feeding rollers acting on both side edges of the copy paper becomes uneven, resulting in so-called slanted paper feeding. More specifically, when copying paper is relatively large, the pressure applied by the pressure lever is mainly transmitted to the feeding roller located in the center, and this feeding roller acts on the copying paper. Due to this, the balance maintaining effect between the feed rollers located on both sides is weakened, and the pressure contact force is unevenly transmitted to the feed rollers located on both sides. If an imbalance occurs between the pressing forces transmitted to the feeding rollers located on both sides, the pressing force of the feeding rollers will be different at both ends of the copy paper, and the above pressing force will be different when feeding the copy paper. On the smaller side, slippage is more likely to occur between the copy paper and the feeding roller, thus causing slanted paper feeding.

Furthermore, in the paper feeding device disclosed in Japanese Patent Application Laid-Open No. 59-57838, the pressure contact mechanism includes an elastically biased pressure contact lever and a pair of rollers disposed on the pressure contact lever with an interval in the lateral direction. The rollers are configured to act on both sides of the mounting plate. In such a paper feeding device, the feeding rollers located on both sides are arranged on both sides of the pair of rollers, and the feeding roller located in the center is arranged between the pair of rollers. Therefore, even when feeding a relatively large copy paper, the pressing force of the pressing lever is substantially uniformly transmitted to the feeding rollers located on both sides via the pair of rollers. However, if there is a manufacturing error, this will cause an imbalance between the pressing forces transmitted to the feeding rollers located on both sides, which will cause the paper to be fed diagonally as described above.

<Object of the Invention> The present invention has been made in view of the above facts, and its object is to substantially equalize the pressing force of the feeding mechanism acting on both sides of copy paper with a relatively simple structure. An object of the present invention is to provide an improved paper feeding device that can perform the following operations.

<Summary of the Invention> According to the present invention, there is provided a paper feeding device in which a cassette receiving part is provided in a copying machine housing, and a copy paper cassette is detachably attached to the cassette receiving part, and the copy paper cassette is , a paper feeding device comprising a cassette main body having an opening formed in the bottom wall, and a mounting plate rotatably attached to the cassette main body, and on the upper surface of which a stacked sheet of copy paper is placed; The cassette receiver includes a pressure contact lever mechanism that acts on the mounting plate of the copy paper set mounted on the cassette receiver, and a pressure lever mechanism that acts on the uppermost sheet of copy paper in the copy paper cassette. A feeding mechanism is provided for feeding the sheet of copy paper, and the pressure lever mechanism includes a pressure lever that is rotatably mounted on the cassette receiver and elastically biased in a predetermined direction, and a pressure lever that is rotatably mounted on the cassette receiver and is elastically biased in a predetermined direction. The pressure contact means is disposed in a direction perpendicular to the direction, and has a middle portion supported by a support means provided on the pressure contact lever, and both ends are swingable, and both ends of the pressure contact means are connected to the cassette. A sheet feeding device that is brought into pressure contact with the mounting plate through the opening formed in the main body, and the pressure contact force of the both ends of the pressure applying means against the mounting plate is substantially the same. is provided.

<Preferred Specific Examples of the Invention> Hereinafter, preferred specific examples of a paper feeding device constructed according to the present invention will be described with reference to the accompanying drawings.

Referring to FIG. 1, the illustrated paper feeding device includes a copy paper cassette 2 that is detachably mounted on a cassette receiver (not shown) provided within a copy machine housing. The copy paper cassette 2 includes a box-shaped cassette body 4 with an open top.
Locking pawls (not shown) are provided at both corners of the front end. At the front end of the bottom wall 6 of the cassette body 4, a rectangular opening 8 is formed approximately at the center in the lateral direction (left-right direction in FIG. 1). A mounting plate 10 is housed within the cassette main body 4, and the mounting plate 10 is mounted so as to be pivotable with its rear end as a fulcrum. The mounting plate 10 is supported so as to be pivotable about a protrusion (not shown) provided in the horizontal direction substantially in the center of the bottom wall 6 of the cassette main body 4, and
It is preferable that it is swingably mounted on both sides of the cassette main body 4 over a predetermined range. This board 1
0, a stacked sheet copy paper 12 is placed on top of the sheet copy paper 12. Such a copy paper cassette 2 is disclosed in Japanese Patent Application Laid-open No. 1983-
It has substantially the same configuration as that disclosed in Publication No. 57838.

On the other hand, a pressure contact lever mechanism 14 and a feeding mechanism 16 are disposed in a cassette receiver (not shown) provided within the copying machine housing. Referring to FIG. 2 together with FIG. 1, the pressure contact lever mechanism 14 shown in FIG.
includes a pressure contact lever 18 and a pressure contact action means 20 attached to the pressure contact lever 18. The cassette receiving portion has a shaft member 22 rotatably extending in the lateral direction, that is, in the left-right direction in FIG. A bolt (not shown) is attached to the lateral intermediate portion of the shaft member 22.
One end (base) of the pressure contact lever 18 is fixed. In the specific example, although not shown, the shaft member 22 is configured to be biased clockwise in FIG. 2 (more specifically, clockwise when viewed from the lower right in FIG. 2) by the action of a spring member. Therefore, the pressure contact lever 18 is indicated by the arrow 24 in FIG.
It is elastically biased in the direction shown by . Also,
The pressing means 20 has a shaft member 26 extending in the lateral direction, that is, in a direction perpendicular to the feeding direction of the sheet-like copy paper 12, and a pair of rollers 28a and 28b. Bent portions 30a and 30b bent upward are provided at both ends of the pressure contact lever 18, and long holes 32a and 32b extending in the vertical direction are formed at the tips of the bent portions 30a and 30b. The shaft member 26 is installed in the long holes 32a and 32b. A roller 28a is rotatably attached to one end of the shaft member 26 that protrudes outward from the bent portion 30a, and a roller 28b is rotatably attached to the other end that protrudes outward from the bent portion 30b. has been done. Locking members 34a and 34b are attached to both ends of the shaft member 26 to prevent the rollers 28a and 28b from coming off the shaft member 26. In the specific example, a protrusion 36 as a supporting means that protrudes upward is further provided at approximately the center in the lateral direction of the distal end of the pressure contact lever 18, and the intermediate portion of the shaft member 26 is supported by the protrusion 36. It is becoming more and more common. As stated above, Col. 28
The shaft member 26 having a and 28b is vertically movable over a predetermined range, and furthermore, the shaft member 26 has a pressure contact lever 1.
It can freely swing in the vertical direction using the protrusion 36 of No. 8 as a fulcrum.

The illustrated feeding mechanism 16 disposed above the pressure contact lever mechanism 14 includes a rotational support shaft 38 that is rotated in a predetermined direction and three feeding rollers 40a and 40b mounted on the rotational support shaft 38. and 40c. In a specific example, as shown in FIG. 1, feeding rollers 40b and 40c on both sides are arranged above both sides of the rollers 28a and 28b, and the central feeding roller 40a is arranged above the middle of the rollers 28a and 28b. It is arranged.

The other structure of the above-mentioned cassette receiver is substantially the same as that disclosed in Japanese Patent Application Laid-Open No. 59-57838.

When a relatively large stacked sheet of copy paper 12 is stored in the copy paper cassette 2 as described above and is detachably attached to the cassette receiver (not shown) as required, the image shown in FIG. As shown, the pressure contact lever 18 is moved by the action of a spring member (not shown).
are elastically biased in the direction shown by the arrow 24 (FIG. 2), and the rollers 28a and 28b attached to the tip of the pressure lever 18 are mounted through the opening 8 formed in the bottom wall 6 of the cassette body 4. It acts on the lower surface of the tip of the plate 10. When the rollers 28a and 28b act on the mounting plate 10, the pressing force by the pressing lever 18 is transmitted to the shaft member 26 via the protrusion 36, and a part of this pressing force is applied to the mounting plate 10 via the rollers 28a. The signal is transmitted to one side (the right side in FIG. 1), and the remainder is transmitted to the mounting plate 1 via the rollers 28b.
0 is transmitted to the other side (the left side in FIG. 1).
Therefore, at this time, since the shaft member 26 is swingable about the protrusion 36, the pressure force acting on the mounting plate 10 via the rollers 28a and the pressure force acting on the mounting plate 10 via the rollers 28b are generated. The pressure contact forces are balanced and become substantially equal. The pressing force acting on the mounting plate 10 via the roller 28a is further transmitted to the feeding rollers 40a and 40b via the sheet copy paper 12, and the pressing force acting on the mounting plate 10 via the roller 28b. is further transmitted to the feeding rollers 40a and 40c via the sheet-like copy paper 12, and therefore, the pressing force acts on the mounting plate 10 via the rollers 28a and the mounting plate 10 via the rollers 28b. When the pressure contact forces are substantially equal, the pressure contact forces transmitted to the feed rollers 40b and 40c on both sides are also substantially equal. As described above, the pressing force with which the feeding roller 40b on one side presses the uppermost copy sheet is substantially equal to the pressing force with which the feeding roller 40c on the other side presses the uppermost copy sheet, The pressing forces acting on both sides of the top copy sheet are balanced.

When the rotation support shaft 38 is rotated in a predetermined direction in such a state, the feeding rollers 40a, 40b, and 40c act on the uppermost copy paper to move it in a predetermined direction, and thus the uppermost copy paper is It is sent out from the cassette main body 4. At the time of such feeding, since the pressing force by the feeding roller 40b and the pressing force by the feeding roller 40c are substantially equal, both sides of the sheet-like copy paper are moved substantially equally, and oblique feeding is ensured. Prevented.

On the other hand, when a relatively small size sheet of copy paper is stored in the copy paper cassette 2 and detachably attached to the cassette receiver (not shown), the rollers 28a and The rollers 28b act on the mounting plate 10, so that the sheet-like copy paper on the mounting plate 10 is pressed against the feeding roller 40a located at the center. In such a case, press lever 1
As described above, the pressure contact force caused by The upper sheet copy paper can be sent out as required.

In the paper feeding device as described above, the following points should be further noted. That is, since the pressure contact force transmitted to the feed rollers 40b and 40c on both sides is balanced by the pressure contact lever mechanism 14, only an improvement is made to the conventional pressure contact lever mechanism provided in the cassette receiver. This can be achieved with a relatively simple configuration, and slanted paper feeding can be reliably prevented.

Although preferred specific examples of the paper feeding device configured according to the present invention have been described above, the present invention is not limited to such specific examples, and various modifications and changes can be made without departing from the scope of the present invention. is possible.

For example, in the specific example, rollers 28a and 2
8b is brought into direct contact with the lower surface of the mounting plate 10, but if desired, a paper feed compensation piece may be provided on the lower surface of the mounting plate 10 to compensate for changes in the pressing force due to the weight of the sheet copy paper. may be provided, and the rollers 28a and 28b may be brought into contact with such sheet feeding compensating pieces.

<Effects of the Invention> The paper feeding device according to the present invention is constructed as described above, and the pressing means that acts on the loading plate through the opening formed in the cassette main body is arranged in a direction perpendicular to the feeding direction of the sheet-like copy paper. A press-contacting device is provided with a press-contacting means which is arranged and whose middle part is supported by a support means provided on the press-contacting lever and whose both ends are swingable, and in which both ends of the press-contacting device act on the riding plate. Since the forces are substantially the same, the contact forces transmitted to the feed mechanism through the mounting plate and the sheet of copy paper are substantially equal. Therefore, the pressing force of the feeding mechanism acting on the sheet of copy paper is substantially equal, and both sides of the sheet of copy paper are moved substantially equally, thereby reliably preventing slanted paper feeding.

[Brief explanation of the drawing]

FIG. 1 is a simplified diagram, partially in section, of a paper feeding device constructed in accordance with the present invention. FIG. 2 is an exploded perspective view showing the press lever mechanism of the paper feeder of FIG. 1; 2...Copy paper cassette, 4...Cassette body,
6... Bottom wall, 8... Opening, 10... Mounting plate, 12
. . . Laminated sheet copy paper, 14 . . . Pressure lever mechanism, 16 . . . Feeding mechanism, 18 .
...Rollers, 40a, 40b and 40c...Feeding rollers.

Claims (1)

[Scope of Claims] 1. A paper feeding device in which a cassette receiving part is provided in a copying machine housing, and a copy paper cassette is detachably attached to the cassette receiving part, and the copy paper cassette is attached to a bottom wall. In a paper feeding device comprising a cassette main body having an opening formed therein, and a mounting plate rotatably mounted on the cassette main body and on which a stack of sheets of copy paper is placed on the top surface, the cassette receiving portion is provided with: includes a pressure contact lever mechanism that acts on the mounting plate of the copy paper set mounted on the cassette receiver, and a pressure lever mechanism that acts on the uppermost sheet of copy paper in the copy paper cassette to feed it. A feeding mechanism is provided, and the pressing lever mechanism includes a pressing lever that is rotatably mounted on the cassette receiver and elastically biased in a predetermined direction, and a pressing lever that is perpendicular to the feeding direction of the sheet copy paper. a press-contacting means disposed in the direction and having an intermediate portion supported by a support means provided on the press-contacting lever and swingable at both ends, both ends of the press-contacting means being formed on the cassette body; A paper feeding device, which is brought into pressure contact with the mounting plate through the opened opening, and the pressing forces of the both ends of the pressure applying means against the mounting plate are substantially the same. 2. The pressure contact means has a shaft member extending in a direction perpendicular to the feeding direction of the sheet copy paper, and a pair of rollers rotatably mounted on both ends of the shaft member, and the shaft member has an intermediate portion supported by support means provided on the pressure contact lever and is swingable at both ends, and the pair of rollers act on the mounting plate through the opening formed in the cassette body. A paper feeding device according to claim 1. 3. The shaft member is mounted on the pressure contact lever so as to be movable over a predetermined range in the vertical direction, and the intermediate portion of the shaft member is supported by support means provided on the pressure contact lever. Paper feeding device according to item 2. 4. The feeding mechanism includes a rotary support shaft that is rotated in a predetermined direction, and at least three rotary support shafts that are attached to the rotary support shaft.
Claim 2 or 3, wherein the feeding rollers on both sides are disposed on both sides of the rollers, and the central feeding roller is disposed between the rollers. Paper feeding device as described in section.