JPH0215872Y2 - - Google Patents

Description

[Detailed description of the invention] [Technical field] This invention relates to an automatic paper feeder that automatically feeds sheets such as manuscripts and recording paper one by one, and in particular, an automatic paper feeder that can prevent double feeding. This relates to paper devices.

[Prior art]

2. Description of the Related Art Printers, document reading devices, copying machines, and the like require devices that automatically feed sheets such as documents and recording paper. FIG. 1 is a diagram showing a conventional automatic paper feeding device of this type. This is Jitsukaiaki
This is disclosed in Japanese Patent No. 58-50442, and in the figure, 1 is a loading platform on which the sheet 2 is placed, 3 is a movable platform connected to one end of the loading platform 1, and the connection part is the center. It is movable up and down. 4 is a spring member that pushes up the movable table 3;
5 is a feeding roller that feeds the sheets 2 held by the loading table 1 and the movable table 3 one by one, and 6 is a side stopper for holding down the sheets 2.

The sheet 2 placed on the loading platform 1 is held by a spring member 4
is pushed up together with the movable base 3 and pressed against the feeding roller 5. At this time, both corners of the sheet 2 in the conveyance direction are held down by the side stoppers 6. Then, the feeding roller 5 is moved to the movable base 3.
When the sheet 1 rotates in the conveying direction, which is the upward direction of the slope, the topmost sheet of the sheet 1 is peeled off due to the frictional force between the feeding roller 5 and the sheet 2, and at the same time, it is separated from the side stopper 6 and is fed forward as it is. . In this way, the sheets 2 are automatically fed one by one.

However, in such a conventional automatic paper feeder, both corners of the sheet 2 in the transport direction are held down by the side stopper 6 and the feed roller 5 feeds the sheet one by one. When storing the stacked sheets 2 on the loading platform 1, the side stoppers 6 on both sides get in the way and make it difficult to store them, and when the number of remaining sheets becomes small, both corners of the sheets easily come off from the side stoppers 6 on both sides. te2
There was a drawback that double feeding such as sheet feeding occurred.

[Summary of the idea]

This idea was made in order to eliminate the drawbacks of the conventional ones as described above, and it consists of a roughly oval-shaped feeding roller that feeds the sheet while pushing down the movable table, and a feeding roller that feeds the sheet while pushing the movable table downward. By providing a double-feed prevention roller that feeds the sheet along the guide on the conveyance table to the conveyance roller, sheets can be easily stored.
Another object of the present invention is to provide an automatic paper feeder that can prevent double feeding.

[Example of idea]

An embodiment of this invention will be described below with reference to the drawings. In addition, the same reference numerals will be used to describe the same parts as in the prior art.

FIG. 2 is a diagram showing the main structure of the automatic paper feeder according to this invention. In the figure, 1 is sheet 2
The loading platform 3 on which the loading platform 1 is placed is a movable platform having one end 7 connected to the loading platform 1, and is provided so as to be movable up and down about the connection. A spring member 4 supports the movable base 3 and constantly presses the movable base 3 upward. 8 is a guide provided along the end surface of the movable table 3 on the sheet conveyance side; 9 is a stopper for preventing the top surface of the movable table 3 from being higher than the top surface of the conveyance table 10; and 11 is a guide provided for moving the movable table 3 downward. an elliptical feeding roller that peels off and feeds the topmost sheet 2a of the sheet 2 while pushing it down; 12 is a feeding guide provided on the conveying table 10; 13 has appropriate rotational resistance; The uppermost sheet 2a is driven and peeled off as the feeding roller 11 rotates.
The sheet 2a is fed along the feeding guide 12 by a double feeding prevention roller that feeds the sheet 2a while pressing it along the circumference of the feeding roller 11. 14 is a spring for pushing up the double feed prevention roller 13; 15, 16;
are the feeding roller 11 and double feeding prevention roller 13, respectively.
These are upper and lower conveyance rollers that convey the sheet 2a fed forward by the upper and lower conveyance rollers.

Next, the operation will be explained with reference to FIG.

In the automatic sheet feeder configured as described above, a sheet 2 such as a document is held by a stacking table 1 and a movable table 3, as shown in FIG. 3a. When the elliptical feeding roller 11 rotates while pressing the upper part of the sheet 2 near the end surface, the sheet 2
is pressed obliquely backward and moves downward together with the movable base 3, and the end surface of the movable base 3 draws an arc along the guide 8. At the same time, the uppermost sheet 2a is peeled off by the frictional force with the feeding roller 11 and moves forward as the feeding roller 11 rotates (see FIG. 3b). This peeled sheet 2a is
The paper is fed to the transport rollers 15 and 16 along the feeding guide 12 while being sandwiched between the feeding roller 11 and the double feeding prevention roller 13 which is pressed downward by the feeding roller 11. (See Figure 3c). At this time, two or more sheets 2 are peeled off and the paper feed roller 1
When the sheet 1 is held between the sheet 1 and the double feed roller 13, the friction coefficient between the double feed prevention roller 13 and the bottom sheet 2a is greater than the friction coefficient between the sheet 2, so the double feed maintains appropriate rotational resistance. The prevention roller 13 stops rotating, and the sheets below the top sheet 2a are stopped from moving by the frictional force between them and the top sheet 2a.
Only a is fed by the rotational drive of the feeding roller 11. Next, the sheet 2a fed to the conveyance rollers 15 and 16 is further moved forward along the conveyance table 10 while being held between the conveyance rollers 15 and 16 (see FIG. 3d). Then, from the time when the long diameter portion of the feeding roller 11 comes into contact with the double-feed prevention roller 13, the force that pushes the movable base 3 downward becomes weaker, and the spring member 4 is applied to the movable base 3 and the movable base 3 in proportion to the pressing force. The seat 2 is pushed upward, and the movable base 3 returns to its original state. At this time, as described above, the double feeding prevention roller 13
is fed while being pressed against the feeding guide 12 by the spring 14 (see FIG. 3e). When the sheet 2a is fed to the transport rollers 15 and 16, the double feed prevention roller 13 is pushed upward by the spring 14 and returns to its original state (FIG. 3a).

In this way, one sheet can be reliably fed during one rotation of the elliptical feeding roller 11. At this time, the height of the sheets 2a to be fed is kept substantially constant, and double feeding such as two-sheet feeding can be avoided. Furthermore, the shape of the feeding roller 11 is as follows:
Similar results can be obtained not only in the above-mentioned elliptical shape but also in other shapes, such as semicircular shapes.

FIG. 4 is a diagram showing an example in which the loading platform 1 is tilted with respect to the movable platform 10. In this case as well, double feeding can be prevented, and the sheets 2 can be stored in the same way as in the case of FIG. When doing so, it is only necessary to place it on the loading table 1 and the movable table 3, and there is no need to pay attention to the side stoppers as in the conventional case, making it easier to store.

Note that it is also possible to integrally form the loading table 1, movable table 3, spring member 4, guide 8, etc. as a cassette, which further improves handling.

[Effect of idea]

As explained above, according to this invention, there is a substantially oval-shaped feeding roller that feeds the sheet while pushing down the movable table, and a conveying roller that moves the fed sheet along the guide on the conveying table. Since a double-feed prevention roller is provided to feed the sheets, double-feeding such as two-sheet feeding can be reliably prevented, and sheets can be easily stored.

[Brief explanation of drawings]

FIG. 1 is a side sectional view showing the main structure of a conventional automatic paper feeder, FIG. 2 is a side sectional view showing the main structure of the automatic paper feeder according to this invention, and FIGS. 3a, b,
c, d, and e are sectional views for explaining the operation of the automatic paper feeder shown in FIG. 2, and FIG. 4 is a side sectional view showing an example in which the loading platform is tilted. 1... Loading table, 2, 2a... Sheet, 3... Movable table, 4... Spring member, 5, 11... Feeding roller, 7... End, 10... Conveying table, 12... Feeding guide, 13...Double feeding prevention roller. Note that the same reference numerals in the figures indicate the same parts.

Claims (1)

[Scope of claim for utility model registration] (1) An automatic system that automatically feeds the sheets 2 placed on the loading platform 1 one by one and also allows the loading platform 1 and a part thereof to be moved up and down. In the paper feeding device, while pushing down the movable table 3, which is a part of the loading table 1, together with the loaded sheet 2,
The upper sheet 2 is then moved to the double feed prevention roller 1.
An oval-shaped feeding roller 11 for feeding in three directions; and an oval-shaped feeding roller 1 that is driven to rotate in contact with the rotation of this feeding roller 11.
The sheet 2 is moved up and down by the rotation of the conveyor roller 1, and the sheet 2 is conveyed along the guide 12 on the conveyor table 10.
A double-feed prevention roller 13 that maintains an appropriate rotational resistance for feeding the sheets 5 and 16 is provided, and when two or more sheets 2 are fed between the contact between the feed roller 11 and the double-feed prevention roller 13, An automatic paper feeder characterized in that the feed prevention roller 13 is configured to stop rotating. (2) The automatic sheet feeding device according to claim 1, wherein the feeding roller 11 has an elliptical shape. (3) The automatic sheet feeding device according to claim 1, wherein the feeding roller 11 is formed in a semicircular shape. (4) Utility model registration claim 1, characterized in that the loading platform 1 is inclined with respect to the conveying platform 10
The automatic paper feeding device according to any one of Items 1 to 3.