JP2001199580A - Feeding mechanism - Google Patents

Abstract

(57) [Problem] To provide a feeding mechanism capable of feeding a thick medium even in a feeding path having a small curvature. SOLUTION: An auxiliary press-contact plate 12 is swingably provided downstream of a position where a hopping roller 4 and a separation pad 5 are pressed against each other in a medium feeding direction. The auxiliary pressing plate 12 has a butt guide 14 against which the leading end of the medium 2 abuts, and a protrusion 15 formed on the opposite side of the butt guide 14.
Having. When the thick medium 2 collides with the guide portion 14, the auxiliary pressing plate 12 swings, and the protrusion 14
Rises to wind the medium 2 around the hopping roller 4. Thereby, the medium 2 by the hopping roller 4
Increase the feeding power of

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a feeding mechanism provided in a printing apparatus or a copying apparatus for feeding a medium by a feeding roller.

[0002]

2. Description of the Related Art Conventionally, in printing apparatuses and copying apparatuses,
The hopping roller is pressed against the recording medium stored in the tray, and the hopping roller is rotated to feed or print the medium one by one from the tray to perform printing or copying. The problem with the downsizing of the printing apparatus is the arrangement of the medium feed path, but the feed path immediately after the hopping roller unwinds the medium from the tray is a curved feed path with a small curvature. As a result, devices with a reduced installation area have been increasing.

[0003] A separation pad is pressed against the hopping roller, and the medium fed from the tray is separated one by one by the separation pad. In particular, in a small-sized apparatus, the separation pad is used to simplify the mechanism. There is a mechanism in which a mechanism for pressing / releasing the pad against the hopping roller is not provided, and the separation pad is always kept pressed against the hopping roller.

If the pressing force of the separation pad against the hopping roller is too strong, image expansion of a printed image on a thin medium and a dropping shock when the end of the medium leaves the hopping roller appear on the printed image. Therefore, the pressure contact force of the separation pad is set to an appropriate value so that such a phenomenon does not appear.

[0005]

However, in the above-mentioned conventional feeding mechanism, when printing on a thick medium, the thick medium is fed while the leading end of the thick medium is abutted against a feeding path having a small curvature. Since the rigidity is large, the load on the front end of the medium received from the feeding path becomes large, and the feeding force is required to overcome the load. The feeding force of the medium depends on the pressing force between the hopping roller and the medium, but if the pressing force of the separation pad against the hopping roller is set for a thin medium, the feeding force enough to feed a thick medium is obtained. Was not always possible.

[0006]

According to the present invention, there is provided a feed mechanism for pressing a medium against a feed roller and feeding the medium by rotation of the feed roller. An abutting portion disposed so as to be swingable along a feeding path, which is located downstream of the swinging fulcrum in the feeding direction, and against which the leading end of the rigid medium sent out by the feeding roller abuts; An auxiliary pressing member having a pressing portion that is positioned upstream of the fulcrum in the feeding direction and oscillates to press the medium against the feeding roller is provided. The pressing portion may be provided with a projection, and the projection may wind the medium around the feeding roller when the auxiliary pressing member swings. Further, a rotatable roller may be provided at the press contact portion so as to face the feed roller, and the rotatable roller may press the medium against the feed roller when the auxiliary press member swings.

The paper feeding mechanism includes a storage tray for storing the medium, and a separation pad for separating the medium fed by pressing the feeding roller against the uppermost medium stored in the storage tray one by one. When the auxiliary pressure contact member swings, the pressure contact portion changes the pressure contact angle of the separation pad to the feed roller to increase the amount of the medium wound around the feed roller. It may be.

[0008] Further, a storage tray for storing the medium, a feed roller that presses against the uppermost medium of the medium stored in the storage tray and rotates to feed the medium, and presses against the feed roller, In a feeding mechanism having a separation pad that separates the media fed by the feeding roller one by one, the media is swingably disposed along a feeding path through which the media is fed, and is provided at a swing fulcrum. An abutting portion, which is located downstream in the feeding direction and abuts against the leading end of the rigid medium sent out by the feeding roller, and the separation pad which is located upstream in the feeding direction with respect to a swing fulcrum and swings. And an auxiliary press-contact member having a press-contact portion for increasing a press-contact force on the feeding roller.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a side view illustrating a feeding mechanism according to a first embodiment of the present invention, and FIG. 2 is a perspective view illustrating an auxiliary pressing plate according to the first embodiment.

In FIG. 1, a feeding mechanism 1 according to the first embodiment is in contact with a medium tray 3 for stacking and storing media 2, a hopping roller 4 for feeding out the media 2 one by one, and a hopping roller 4. It is composed of a separation pad 5 and a curved medium guide 6 for transporting the fed medium 2. The medium 2 stored in the medium tray 3 is pressed upward by pressing means (not shown), and the uppermost medium 2 is pressed against the hopping roller 4.

The separation pad 5 is attached to a separation frame 7. The separation frame 7 is supported by a spring 9 so as to be able to move up and down, and the spring 9 is supported by a support member 8. The spring 9 presses the separation pad 5 against the hopping roller 4. The separation pad 5 separates the medium 2 fed by the hopping roller 4 into one sheet. The medium guide 6 includes an inner guide 10 and an outer guide 11, and the guides 10 and 11 form a feed path 16 having a small curvature. Outer guide 11
Is provided with an auxiliary pressing plate 12.

Referring to FIGS. 1 and 2, the auxiliary pressing plate 1
2 is provided so as to be swingable about a fulcrum 13,
3 (the downstream side in the feeding direction of the medium 2) is an outer guide 11
Abutment guide portion 14 having substantially the same curvature as that of fulcrum portion 13, and projection portion 15 is formed on the right side of fulcrum portion 13. The abutting guide portion 14 is provided so as to protrude inside the feeding path 16 from the outer guide 11 and is provided with the hopping roller 4.
As a result, the leading end of the medium 2 fed out abuts against the abutting guide portion 14 before the outer guide 11. As shown in FIG. 3, a spring 17 is disposed outside the abutting guide portion 14, and the spring 17 presses the auxiliary press-contact plate 12 to swing clockwise around the fulcrum portion 13. .

Next, the operation of the first embodiment will be further described with reference to FIGS. 3 and 4 are side views showing the operation of the first embodiment. FIG. 3 shows the case of feeding a thin medium, and FIG. 4 shows the case of feeding a thick medium. First, the case where the medium 2 is a thin medium will be described.

The uppermost medium 2 a among the mediums 2 a set on the medium tray 3 is pressed by a hopping roller 4. By rotating the hopping roller 4 in the clockwise direction, the uppermost medium 2 a is fed out and fed to the separation pad 5. The separation pad 5 separates the uppermost medium 2a from the second and subsequent media 2a, and the uppermost medium 2a is further fed by the hopping roller 4.

At this time, the auxiliary pressing plate 12 is pressed by the spring 17 to the position shown in FIG.
Reference numeral 5 denotes a position at which the leading end of the medium 2a can easily pass over the upper part. The auxiliary pressing plate 12 is stopped from swinging clockwise by the spring 17 at the position shown in FIG. 3 by a stopper (not shown).

The leading end of the separated medium 2a abuts against the inside of the abutting guide portion 14 of the auxiliary pressing plate 12. Since the thin medium 2a has no rigidity, it is guided by the auxiliary press plate 12 and the outer guide 11 as it is, and is further fed through the feeding path 16.

Next, the case of feeding a thick medium will be described.
The above operation is the same until the medium 2b is fed out of the medium tray 3 by the rotation of the hopping roller 4 and further separated into one by the separation pad 5. Separation pad 5
, The leading end of the thick medium 2 b abuts against the inside of the abutting guide portion 14 of the auxiliary press plate 12. Since the thick medium 2b has rigidity, the auxiliary press-contact plate 12 is moved by the spring 1
7 and counterclockwise in FIG. 4 around the fulcrum 13. The pressing force of the spring 17 is
The pressing force of the thick medium having rigidity is set to be smaller than the pressing force of the medium when the medium presses against the auxiliary pressing plate 12.

When the auxiliary pressing plate 12 swings, the projection 15 of the auxiliary pressing plate 12 moves upward and approaches the hopping roller 4. Thus, the amount of the medium 2b wound around the hopping roller 4 increases. That is, the winding amount θ2 of the thick medium 2b around the hopping roller 4 shown in FIG. 4 is larger than the winding amount θ1 of the thin medium 2a around the hopping roller 4 shown in FIG. The medium 2b increases the feeding force of the hopping roller 4 by increasing the winding amount.

From the fulcrum 13 serving as the swing center, the medium 2b
Of the auxiliary press-contact plate 12
The distance from the fulcrum 13 to the projection 15 on the auxiliary press plate 12 is the distance from the fulcrum 13 to the position (point of force)
By setting the distance to the position (the point of action) that is in contact with b sufficiently long, the force for lifting the protrusion 15 by the principle of leverage increases.

The swing of the auxiliary press plate 12 stops when the inside of the abutting guide portion 14 is flush with the inside 11a of the outer guide 11. This is the state shown in FIG. After the medium 2b collides with the abutting guide portion 14, the medium 2b is fed by the increased feeding force, the leading end of the medium 2b slides on the auxiliary press-contact plate 12, and eventually moves to the inner guide 10 as shown by the dotted line in FIG. Abuts on the lower end 10a. From here, the medium 2b enters the feed path 16 having a small curvature. For this purpose, the medium 2b must be bent against rigidity. When the medium 2b starts to bend, a maximum feeding force is required. In the present embodiment, since the feeding force is increased by the action of the auxiliary pressing plate 12, the medium 2b is bent and the feeding path 16 is fed.

Once bent, the medium 2b is fed with a modest feeding force. Therefore, after the leading end of the medium 2b enters the feeding path 16, the force with which the medium 2b presses the auxiliary pressing plate 12 is reduced, and the auxiliary pressing plate 12 returns to the original position (the position shown in FIG. 3) and returns to the original position.
The medium 2b continues to be fed even if the feeding force for b becomes the original magnitude.

As described above, according to the first embodiment,
When the thin medium 2a is fed, the feeding force is not increased, and only when the thick medium 2b is fed, the feeding force by the hopping roller 4 is increased. Becomes possible.

Next, a second embodiment will be described. FIG. 5 is a side view showing a feeding mechanism according to the second embodiment. FIG.
In the feeding mechanism according to the second embodiment, an auxiliary pressing plate 21 is provided so as to be swingable about a fulcrum 22.
The auxiliary pressing plate 21 has an abutting guide portion 23,
On the opposite side, an auxiliary roller 24 is rotatably provided. As in the case of the auxiliary pressing plate 12 of the first embodiment, when the leading end of the thick medium 2b abuts against the abutting guide portion 23, the auxiliary pressing plate 21 swings counterclockwise around the fulcrum portion 22. Then, the auxiliary roller 24 moves upward. The auxiliary roller 24 is in pressure contact with the hopping roller 4 via the medium 2b. Other configurations are the same as those of the first embodiment.

Next, the case of feeding a thick medium in the second embodiment will be described. The medium 2b is fed out of the medium tray 3 by the rotation of the hopping roller 4, and is further separated into one by a separation pad 5. After passing through the separation pad 5, the leading end of the thick medium 2b is
Abuts the inside of the abutting guide portion 23. Since the thick medium 2b has rigidity, the auxiliary pressure contact plate 21 swings counterclockwise in FIG. 5 around the fulcrum 22 against the pressing force of the spring 17 when the leading end of the medium 2b abuts. The pressing force of the spring 17 is set to be smaller than the pressing force of a thick medium having rigidity when the medium presses against the auxiliary pressing plate 21.

When the auxiliary pressing plate 21 swings, the auxiliary roller 24 of the auxiliary pressing plate 21 moves upward, and presses against the hopping roller 4 via the medium 2b. Thus, the amount of the medium 2b wound around the hopping roller 4 increases. The medium 2b increases the feeding force of the hopping roller 4 by increasing the winding amount.

The swinging of the auxiliary press plate 21 is stopped when the inside of the abutting guide portion 23 is flush with the inside 11a of the outer guide 11. After the medium 2b collides with the abutment guide 23, the medium 2b is fed by the increased feeding force. The leading end of the medium 2b slides on the auxiliary pressing plate 21 and enters the feeding path 16 having a small curvature. Here, the medium 2b starts to bend due to the increased feeding force, and is fed through the feeding path 16.

As described above, according to the second embodiment,
When feeding the thick medium 2b, the auxiliary roller 24 of the auxiliary pressing plate 21 is moved by the hopping roller 4 via the medium 2b.
When the amount of winding around the hopping roller 4 is the same as in the first embodiment, the feeding force is further increased as compared with the first embodiment. Can be increased.

Next, a third embodiment will be described. FIG. 6 is a side view showing a feeding mechanism according to the third embodiment. FIG.
In the feeding mechanism according to the third embodiment, an auxiliary pressing plate 31 is provided so as to be swingable about a fulcrum 32,
The auxiliary pressing plate 31 has a butting guide portion 33,
A support portion 34 for supporting the spring 9 is formed on the opposite side of the fulcrum portion 32. Auxiliary pressure plate 3
1, similarly to the auxiliary pressing plate 12 of the first embodiment, when the leading end of the thick medium 2 b abuts against the abutting guide portion 33, the medium 1 b swings counterclockwise around the fulcrum portion 32 and is supported. The part 34 moves upward. Other configurations are the same as those of the first embodiment.

Next, the case of feeding a thick medium in the third embodiment will be described. The medium 2b is fed out of the medium tray 3 by the rotation of the hopping roller 4, and is further separated into one by a separation pad 5. After passing through the separation pad 5, the tip of the thick medium 2b is
Abuts the inside of the abutting guide portion 33. Since the thick medium 2b has rigidity, when the leading end of the medium 2b abuts, the auxiliary press-contact plate 31 swings counterclockwise in FIG. The pressing force of the spring 17 is set smaller than the pressing force of a thick rigid medium when the medium is abutted against the auxiliary pressing plate 31.

When the auxiliary pressing plate 31 swings, the support portion 34 moves upward, and the spring 9 is lifted. The lifted spring 9 increases the force of pressing the separation pad 5 against the hopping roller 4 via the separation frame 7. As a result, the force with which the medium 2b is pressed against the hopping roller 4 is increased, and the feeding force of the medium 2b by the hopping roller 4 is increased.

The swinging of the auxiliary pressing plate 31 stops when the inside of the abutting guide portion 33 is flush with the inside 11a of the outer guide 11. After the medium 2b collides with the abutting guide portion 33, the medium 2b is fed by the increased feeding force. The leading end of the medium 2b moves while sliding on the auxiliary pressing plate 31, and enters the feeding path 16 having a small curvature. Here, the medium 2b starts to bend due to the increased feeding force, and is fed through the feeding path 16.

As described above, according to the third embodiment,
When feeding the thick medium 2b, the support portion 34 of the auxiliary pressing plate 31 raises the spring 9 pressing the separation pad 5 and strengthens the force of the separation pad 5 pressing the hopping roller 4, so that the hopping of the medium 2b is performed. The feeding force by the roller 4 is increased. As described above, in the present embodiment, the feeding force is increased without bringing the auxiliary pressing plate 31 into direct contact with the medium 2b, so that the feeding force is reduced without wrinkling or damaging the medium due to contact with the medium 2b. Can be increased.

Next, a fourth embodiment will be described. FIG. 7 is a side view showing a feeding mechanism according to the fourth embodiment. FIG.
In the feeding mechanism according to the fourth embodiment, an auxiliary pressing plate 41 is provided so as to be swingable about a fulcrum 42,
The auxiliary pressing plate 41 has a butting guide portion 43,
An engagement portion 44 is formed on the opposite side of the fulcrum portion 42. The separation frame 7 supporting the separation pad 5 is provided with a protrusion 45 at a position where the protrusion 45 can be engaged with the engagement portion 44. The protrusions 45 are formed on both sides of the hopping roller 4.

The separation frame 7 is movable vertically.
It is swingably supported by a spring 9. As in the case of the auxiliary pressing plate 12 of the first embodiment, the auxiliary pressing plate 41 swings counterclockwise around the fulcrum portion 42 when the leading end of the thick medium 2b abuts against the abutting guide portion 43. Then, the engagement portion 44 moves upward.
Other configurations are the same as those of the first embodiment.

Next, the operation of the fourth embodiment will be further described with reference to FIGS. 8 and 8 are side views showing the operation of the fourth embodiment. FIG. 8 shows the case of feeding a thin medium, and FIG. 9 shows the case of feeding a thick medium. First, the case of feeding a thin medium will be described.

The uppermost medium 2 a among the mediums 2 a set on the medium tray 3 is pressed by the hopping roller 4. By rotating the hopping roller 4 in the clockwise direction, the uppermost medium 2 a is fed out and fed to the separation pad 5. The separation pad 5 separates the uppermost medium 2a from the second and subsequent media 2a, and the uppermost medium 2a is further fed by the hopping roller 4.

At this time, the auxiliary pressing plate 41 is pressed to the position shown in FIG. 8 by the spring 17 and stops at this position, and the medium 2 a passes over the protrusion 45. The leading end of the separated medium 2a abuts against the inside of the abutting guide portion 14 of the auxiliary pressing plate 12. Since the thin medium 2a has no rigidity, the auxiliary pressing plate 1
The feed path 16 is further fed by being guided by the second and outer guides 11.

Next, the case of feeding a thick medium will be described.
The above operation is the same until the medium 2b is fed from the medium tray 3 by the rotation of the hopping roller 4 and further separated into one by the separation pad 5. Separation pad 5
, The leading end of the thick medium 2 b passes above the protrusion 45, and the abutting guide 4
It hits inside 3. Since the thick medium 2b has rigidity, the auxiliary press-contact plate 41 comes into contact with the spring 17 when the leading end of the medium 2b abuts against the abutting guide 43.
9 in a counterclockwise direction in FIG. 9 around the fulcrum portion 42 against the pressing force. The pressing force of the spring 17 is set to be smaller than the pressing force of a thick medium having rigidity when the medium presses against the auxiliary pressing plate 41.

When the auxiliary pressing plate 41 swings, the engaging portion 44 of the auxiliary pressing plate 41 moves upward, and engages with the projecting portion 45 formed on the separation frame 7 to push up the projecting portion 45. As a result, the left side (downstream in the feeding direction) of the separation frame 7 in FIG. 9 rises, and the right side (upstream side in the feeding direction) in FIG. Due to the swing of the separation frame 7, the amount of the medium 2b newly wound around the hopping roller 4 on the downstream side of the separation pad 5 in the feeding direction increases. That is, the winding amount θ3 of the thick medium 2b around the hopping roller 4 shown in FIG. 9 is larger than the winding amount θ1 of the thin medium 2a around the hopping roller 4 shown in FIG. The medium 2b increases the feeding force of the hopping roller 4 by increasing the winding amount.

The swinging of the auxiliary pressing plate 41 stops when the inside of the abutting guide portion 43 is flush with the inside 11a of the outer guide 11. This is the state shown in FIG. After the medium 2b abuts against the abutting guide portion 43, the medium 2b is fed by the increased feeding force, and the tip moves while sliding on the auxiliary pressing plate 41, and then the medium 2b enters the feeding path 16 having a small curvature. However, since the feeding force of the medium 2b is increased by the elevation of the protrusion 45,
b is bent to feed the feed path 16.

As described above, according to the fourth embodiment,
When the thick medium 2b is fed, the projection 45 is raised by the swinging of the auxiliary pressing plate 41, and the angle at which the separation pad 5 is pressed against the hopping roller 4 is further increased on the downstream side in the feeding direction. The feeding force of the medium 2b by the hopping roller 4 is increased without increasing the pressing force against the roller 4, and therefore, regardless of the thickness of the medium 2, there is no fear of image elongation or hopping shock. The feeding force of the medium can be increased.

[0042]

As described above in detail, according to the present invention, the auxiliary press-contact plate is provided so as to be swingable along the medium feeding path, and the leading end of the rigid thick medium abuts against the auxiliary press-contact plate. As a result, the auxiliary pressing plate swings, and the swinging increases the amount of the medium wrapped around the hopping roller or increases the medium pressing force against the hopping roller, thereby increasing the feeding force of the thick medium. Therefore, even when a thick medium is fed through a feeding path having a small curvature, a feeding force capable of feeding is obtained.

[Brief description of the drawings]

FIG. 1 is a side view showing a feeding mechanism according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing an auxiliary press-contact plate according to the first embodiment.

FIG. 3 is a side view illustrating a feeding operation of a thin medium according to the first embodiment.

FIG. 4 is a side view illustrating a feeding operation of a thick medium according to the first embodiment.

FIG. 5 is a side view illustrating a feeding mechanism according to a second embodiment.

FIG. 6 is a side view illustrating a feeding mechanism according to a third embodiment.

FIG. 7 is a side view illustrating a feeding mechanism according to a fourth embodiment.

FIG. 8 is a side view illustrating a feeding operation of a thin medium according to a fourth embodiment.

FIG. 9 is a side view illustrating a feeding operation of a thick medium according to a fourth embodiment.

[Explanation of symbols]

 2 Medium 4 Hopping roller 5 Separation pad 6 Feeding path 9 Spring 12, 21, 31, 41 Auxiliary press-contact plate 15 Protrusion 24 Auxiliary roller 34 Support 44 Engagement 45 Protrusion

Claims (5)

[Claims] 1. A feeding mechanism for pressing a medium against a feeding roller and feeding the medium by rotation of the feeding roller, wherein the feeding mechanism is arranged to be swingable along a feeding path through which the medium is fed. An abutting portion that is located downstream of the swing fulcrum in the feeding direction and abuts against the leading end of the rigid medium sent out by the feeding roller, and that is located upstream of the swing fulcrum in the feeding direction and swings. And a press-contact portion having a press-contact portion for pressing the medium against the feed roller. 2. The feeding mechanism according to claim 1, wherein the pressing portion has a projection, and the projection winds the medium around a feeding roller when the auxiliary pressing member swings. 3. The press-contact portion is provided with a rotatable roller facing the feed roller, and the rotatable roller presses the medium against the feed roller when the auxiliary press member swings. The feeding mechanism as described. 4. A storage tray for storing a medium, and a separation pad for separating one by one the medium fed out by a feed roller being pressed against the uppermost medium of the medium stored in the storage tray, 2. The feeding mechanism according to claim 1, wherein when the auxiliary pressing member swings, the pressing portion changes the pressing angle of the separation pad against the feeding roller to increase the amount of the medium wound around the feeding roller. . 5. A storage tray for storing a medium, a feed roller for pressing the uppermost medium of the medium stored in the storage tray and feeding the medium by rotating, and a press roller for the feed roller, And a separation pad for separating the medium fed by the feed roller one by one, wherein the separation mechanism is provided so as to be swingable along a feeding path through which the medium is fed, and to a swing fulcrum. The abutting portion against which the leading end of the rigid medium sent out by the feeding roller is located downstream in the feeding direction, and the abutting portion, which is located upstream in the feeding direction with respect to the swing fulcrum and swings, and A feeding mechanism comprising an auxiliary pressing member having a pressing portion for increasing a pressing force against a feeding roller.