JPH10297771A - Paper feeder - Google Patents

Abstract

(57) [Problem] To provide a paper feeder that is compact and consumes less power. A document loaded on a hopper table is conveyed by a feeding roller, a separation roller, and the like, and is read by a reading unit. Since the document 4 decreases with the reading, the height of the hopper table 2 must be adjusted to keep the position of the uppermost surface of the document 4 within a predetermined range at all times. When the base 1 is located below the upper position H, the controller 51 drives the motor 18 to move the entire base 1 up and down, and when the base 1 is located above the upper position H. Drives the motor 21 to drive the cam 19
To rotate the hopper table 2 about the swing shaft 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet feeding device used for an image reading device or the like.

[0002]

2. Description of the Related Art In recent years, image reading apparatuses have been widely used for reading an image from a document. And, in order to automatically feed a document to the image reading apparatus,
A document feeder is often provided.

Some image readers for business use attempt to realize efficient reading using a document feeder capable of placing a large amount of documents on a hopper table at a time.

Here, such a document feeder is generally required to satisfy the following conditions.

First, the angle (same as the angle of the hopper table) of the original toward the paper feed roller of the image reading apparatus must be within an allowable range from the ideal angle regardless of the amount of the original on the hopper table. Must. This is because, if the tolerance is out of the allowable range, a paper feeding error occurs, such as jamming of the document or feeding of the document at a time.

[0006] Second, it is desirable that the power for raising and lowering the original (hopper table) be as small as possible. This is because it is desired to save power consumption.

On the other hand, conventional document feeders can be roughly classified into two types: a parallel lift type and a swing type.

Among them, the parallel lift type stacks originals horizontally on a table, raises and lowers the entire table horizontally using an elevating means, and feeds out the uppermost original by a feed roller.

However, according to such a configuration,
Since it is necessary to raise and lower not only the original but also the entire table, there is a problem that the load on the driving source increases and the power consumption increases.

In the swing type, the end of the hopper table is pivotally supported on a fixed pivot, and the hopper table is pivoted about the pivot depending on the amount of documents on the hopper table.

According to this configuration, even when a large amount of originals are placed on the hopper table, the reaction force on the pivot portion of the reaction force against the distributed load due to the original is the static reaction force of the pivot portion. It is burdensome, and the burden on the drive source is unnecessary. For this reason,
The power required for the drive source is smaller than that of the parallel lift type, which is preferable.

However, in such a configuration,
To keep the angle of the hopper table within the allowable range, the length of the hopper table (radius about the shaft support)
Must be lengthened, and the size of the document feeder increases.

Conversely, if the length of the hopper table is reduced, the angle at which the hopper table swings must be increased in order to cope with a large number of documents. However, the reading efficiency is greatly reduced.

[0014]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a compact paper feeder with low power consumption.

[0015]

According to the paper feeder of the present invention, when the document stacking means is below a predetermined height, the document stacking means is raised and lowered in parallel, and the document stacking means is moved to a predetermined height. In the case described above, control is performed so as to swing the document stacking means.

According to the present invention, it is an object of the present invention to provide a compact paper feeder with low power consumption.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS According to the first aspect of the present invention, there is provided an original loading means for loading an original, a feeding means for feeding out the original loaded on the original loading means, and a swinging means for the original loading means. A first control unit for causing the original stacking unit to move up and down in parallel with the original stacking unit. When the original stacking unit is at a predetermined height or less, the second control unit controls the original stacking. A sheet feeding device, wherein the stacking unit is moved up and down, and when the document stacking unit is at a predetermined height or higher, the first control unit swings the document stacking unit. Means that can be made compact without increasing the swing angle of the means, and that power consumption due to the use of the paper feeder can be minimized by only swinging the document stacking means during normal work with a small amount of documents. so That.

The most characteristic feature of the sheet feeding apparatus according to the present invention is that the base, which rotatably supports one end of the hopper table, is configured to be able to move up and down. By feeding the document by performing the movement in two stages, the hopper table on which the document is placed is prevented from rotating more than necessary.

That is, the base can move up and down in the section between the highest position and the lowest position, and the hopper table can rotate in the section between the highest position and the lowest position.

First, when the original is fully loaded on the hopper table, the base is set at the lowest position, the hopper table is also set at the lowest position, and only the base is set with the hopper table stationary. It rises with the decrease. And only when the base reaches its top position,
Next, the hopper table is rotated toward the uppermost position as the number of documents decreases.

When the amount of originals stacked on the hopper table is relatively small, the base is set between the lowermost position and the uppermost position or at the uppermost position, and the hopper table is placed on the uppermost surface of the original. Is set at a rotation position that is a position suitable for paper feeding.

When the base is set between the lowermost position and the uppermost position, as in the case described above, only the base is raised as the number of documents decreases while the hopper table is not moved. Only after the base reaches its uppermost position, the hopper table is rotated toward the uppermost position as the number of documents decreases.

When the base is set at the uppermost position, only the hopper table is rotated to the uppermost position while the uppermost surface of the original is maintained at a position suitable for sheet feeding while the base is not moved. is there.

As described above, by adopting a configuration in which the vertical movement of the base and the rotation of the hopper table are performed in two stages,
The problem of having to rotate the hopper table on which the originals are placed unnecessarily as the number of originals decreases is eliminated, and the originals are fed to the feed roller while maintaining the optimal angle, reducing paper feed errors. The effect of doing so can be achieved.

However, the above configuration and operation are merely examples, and the number of stages in which the vertical movement of the base and the rotation of the hopper table are performed, and the timing of starting the rotation of the hopper table with respect to the position of the base, Or other configurations and operations are arbitrary, and include all ranges that can be selected by those skilled in the art.

Hereinafter, specific examples of the present invention will be described.
FIG. 1 is a block diagram of a sheet feeding device according to an embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes a base of a hopper table 2 on which originals 4 are stacked. The base 1 holds the hopper table 2 so as to be swingable about a swing shaft 3 in the direction of arrow A, and a mechanism to be described later. Is attached to the image reading apparatus main body so as to be able to move up and down (arrow C). Reference numeral 19 denotes a cam that rotates around a shaft 20 by the driving force of a motor 21 attached to the base 1. The shaft that connects the cam 19 and the motor 21 rotates in the direction of arrow B. The hopper table 2 is pushed up and rises in the direction of arrow A.

As shown in FIG. 2, a rack 5
6, 7, and 8 are integrally attached, and mesh with pinions 9, 10, 11, and 12 rotatably attached to the sheet feeding device main body by shafts 13 and 14, respectively. A worm gear 25 fixed to the shaft 13 of the pinions 9 and 11 and a worm gear 26 fixed to the shaft 14 of the pinions 10 and 12 mesh with worms 15 and 16 integrated with the main shaft 17, and the main shaft 17 1
8. Thus, the base 1 is the motor 1
By the driving force of No. 8, it moves up and down integrally with the hopper table 2 (arrow C).

Reference numeral 31 in FIG. 1 denotes a feeding roller for feeding out the originals 4 stacked on the hopper table 2, and is rotated about a shaft 32 in the feed direction of the originals 4 by driving a motor 40. Reference numeral 33 denotes a separation roller for the document 4, which rotates around the shaft 34 in the feed direction of the document 4 by driving the motor 41 and prevents double feeding of the document 4 by combination with the separation plate 46. . The feeding roller 31 is
The arm 35 is connected to the shaft 34 of the separation roller 33.
1. The shaft 32 and the motor 40 rotate integrally about the shaft 34 (arrow D).

With this configuration, when the height of the uppermost surface of the document 4 is changed by being fed out, the feeding roller 31 is also moved up and down in accordance with the change, and the feeding roller 31 is always pressed against the uppermost surface of the document 4. become. Reference numeral 42 denotes a sensor for detecting the arm 35. When the sensor 35 no longer detects the arm 35, the base 1 or the hopper table 2 is raised to raise the uppermost surface of the document 4 to a predetermined height. Can be held within the range.

Reference numeral 43 denotes a document presence / absence sensor. As shown in FIG. 3, a filler 43-1 is attached to a switch 43-3 by a shaft 43-2. Hopper table 2
When the document 4 is placed on the document 43, the switch 43-3 detects that the top surface of the document 4 pushes up the filler 43-1. If there is no manuscript 4, the filler 43
The switch 43-3 does not detect anything because the hole 2-1 of the hopper table 2 is dropped.

Reference numeral 44 denotes a sensor for detecting that the base 1 is at the lowermost position, and reference numeral 45 denotes a sensor for detecting that the base 1 is at the lowermost position.

Reference numerals 36 and 38 denote feed rollers driven by a motor 41, and reference numerals 37 and 39 denote feed rollers 3
6 and 38, respectively.

Reference numeral 51 denotes a control unit for controlling the entire paper feeder; 52, a reading unit for optically reading information of the document 4 and converting it into an electric signal; 53, a reading unit for controlling the reading unit 52; And a reading control unit 54 for outputting to the operation panel of the image reading apparatus.

Next, a specific example of the operation of the main part will be described with reference to FIGS. 4 and 5 are main part configuration diagrams of an image reading apparatus using a sheet feeding device according to an embodiment of the present invention. In the figure, 1, 2, 3, 4, 19, 21,
The configurations represented by 31, 33, 43, 44, and 45 are the same as those described above, and redundant description will be avoided.

FIG. 4A shows a case where the original 4 is fully loaded, and the base 1 and the hopper table 2 are set at their lowest positions. The sensor 45 detects that the base 1 is at the lowest position.

The base 1 can move up and down in the section between the uppermost position and the lowermost position, and the hopper table 2 can rotate in the section between the uppermost position and the lowermost position.

When the document 4 is sequentially fed from the uppermost position by the feeding roller 31, the document amount gradually decreases, so that the base 1 rises in the direction of the arrow in FIG. , The hopper table 2 and the base 1 via the swing shaft 3
(It is not shown in the drawing), and moves up together with the base 1. However, the hopper table 2 does not rotate in principle during this period. Of course, it is optional to rotate the hopper table 2 during this period.

When the base 1 reaches its uppermost position as shown in FIG. 4B, the sensor 44 detects this and stops the ascent of the base 1.

The motor 21 operates when the sensor 44 outputs a detection signal, and rotates the cam 19 connected via a shaft. The cam 19 rotates the cam 19 upward as the document 4 on the hopper table 2 decreases. Since the cam 19 rotates in the direction of the arrow as shown in FIG. 5, the hopper table 2 is urged by the cam 19 and rotates about the swing shaft 3 in the direction of the arrow in FIG.

As described above, when the document 4 is fed and gradually decreases, and finally disappears, the document presence sensor 43
Is detected, and the motor 21 is stopped.
At this time, the hopper table 2 is at its uppermost position.

The operation of the thus configured image reading apparatus according to the present embodiment will be described below with reference to the flowchart of FIG.

In the image reading apparatus according to the present embodiment, the origin position of the base 1 can be set to either one of the upper position H and the lower position L. The controller 51 stores the origin position specified by the operator through the operation panel 54.

First, the control unit 51 operates the base 1 which has been set.
Is checked (step 1), and the origin position is the upper position H
If it is, the process of step 15 is performed, and if it is the lower position L, the process of step 2 is performed.

Here, the case where the origin position of the base 1 is the lower position L will be described. Next, the control unit 51 controls the motor 1
8 to start raising the base 1 (step 2), until the document presence sensor 43 detects the uppermost surface of the document 4 in step 3 or until the sensor 44 detects the base 1 in step 4. The base 1 is raised by repeating the processing of step 3 and step 4. Then, in step 4, the sensor 4
When the base 1 is detected by step 4, the motor 1 is detected in step 5.
After the driving of the base 8 is stopped by stopping the driving of the base 8, the processing after step 15 is performed.

If the document presence sensor 43 detects the uppermost surface of the document 4 in step 3, the sensor 42
Wait for the arm 35 to be detected, that is, until the uppermost surface of the document 4 reaches a predetermined height. When the uppermost surface of the document 4 reaches a predetermined height, the control unit 51 stops lifting the base 1 (step 8), drives the motor 40 and the motor 41 to feed out and transport the document 4, and reads the document. At 52, the information of the document 4 is read. After reading one document, the height of the uppermost surface of the document 4 is checked (step 10), and if it is within a predetermined range, the next document is read at step 9; Motor 18 in step 11
Is driven to start raising the base 1.

Thereafter, the sensor 44 detects that the base 1 has been raised to the upper position H (step 12), or the sensor 42 has raised the height of the uppermost surface of the document 4 to within a predetermined range. Is continued (step 13), and when the base 1 has been raised to the upper position H, the process of step 14 is performed.
If has risen to within the predetermined range, the process returns to step 8 to stop raising the base 1.

That is, in the processing from step 7 to step 14, the originals 4 stacked on the hopper table 2 are fed out one by one by the feeding roller 31 and are sequentially read by the reading unit 52. The amount of the original 4 thus reduced gradually decreases, and the uppermost surface is lowered. Accordingly, the feeding roller 31 also moves down, and as a result, when the height of the uppermost surface of the document 4 falls outside the predetermined range, the arm 35 is not detected by the sensor 42.

Therefore, the base 1 is raised again until the uppermost surface of the document 4 rises within a predetermined range, and the remaining document 4 is read. However, when the base 1 has risen to the upper position H on the way, the raising of the base 1 is stopped, and the operation moves to the swinging operation of the hopper table 2.

Next, the processing when the origin position of the base 1 is the upper position H will be described. First, in step 15,
The control unit 51 drives the motor 21 to drive the elliptical cam 19.
Is rotated in the direction of arrow B, thereby causing the hopper table 2 to start swinging in the direction of arrow A. The swing of the hopper table 2 is detected when the document 4 is detected by the document presence / absence sensor 43 (step 16), or one end of the hopper table 2 opposite to the swing shaft 3 is raised to the uppermost position H. (Step 17) (When the cam 19 rotates 90 degrees, one end of the hopper table 2 has risen to the uppermost position H). If the sensor 43 detects the document 4 in step 16, the hopper table 2 is further raised until the height of the uppermost surface of the document 4 is raised by the sensor 42 to a predetermined range in step 18. Also,
If it is detected in step 17 that the hopper table 2 has risen to the uppermost position H, the processing from step 31 is performed.

After the one end of the hopper table 2 is raised by the processing from step 15 to step 18 until the height of the uppermost surface of the document 4 is within the predetermined range, step 1 is executed.
At 9, the swing of the hopper table 2 is stopped. Thereafter, the motor 40 and the motor 41 are driven to feed one document 4 and read by the reading unit 52 (step 2).
0). The reading in step 20 is performed on the hopper table 2
Until the original 4 loaded on the printer is exhausted (step 21),
Alternatively, the steps are sequentially performed until the height of the uppermost surface of the document 4 is out of the predetermined range (step 22).

In step 21, the original 4 is detected by the sensor 43.
When is no longer detected, the processing after step 31 is performed. Also, in step 22, the original 4 is detected by the sensor 42.
When the height of the uppermost surface of the document 4 is detected to be out of the predetermined range, the hopper table 2 is swung again to raise one end until the height of the uppermost surface of the document 4 is within the predetermined range again (step 23, 24).

Even if the base position of the base 1 is at the lower position L, after the base 1 has been raised to the upper position H (after step 5 or step 14), the processing from step 15 or step 23 onward is performed. Is performed.

When the hopper table 2 swings to the uppermost position in step 17 and when it is detected in step 21 that the document 4 has run out, the processing from step 31 is performed. First, in step 31, the motor 21
To rotate the cam 19 in the direction opposite to the arrow B, thereby swinging the hopper table 2 and lowering one end thereof. Further, when the origin position of the base 1 is set at the lower position L, the motor 18 is driven to lower the base 1 to the lower position L (detected by the sensor 45) (steps 32 and 33). .

[0055]

According to the present invention, the document stacking means can be made compact without increasing the swing angle of the document stacking means, and at the time of normal work with a small amount of documents, the document stacking means is only swung so that the paper feeding device can be operated. Power consumption due to use can be minimized.

[Brief description of the drawings]

FIG. 1 is a block diagram of an image reading apparatus using a sheet feeding device according to an embodiment of the present invention.

FIG. 2 is a perspective view of a base portion of the paper feeding device.

FIG. 3 is an enlarged view of a document presence sensor of the paper feeding device.

FIG. 4 is a configuration diagram of a main part of the paper feeding device.

FIG. 5 is a configuration diagram of a main part of the paper feeding device.

FIG. 6 is an operation flowchart of the sheet feeding device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 base 2 hopper table 4 document 19 cam 31 feed roller 33 separation roller 43 document presence sensor 51 control unit 52 reading unit

Claims (1)

[Claims] An original loading means for loading an original; a feeding means for feeding out the original loaded on the original loading means;
A first control unit for oscillating the document stacking unit; and a second control unit for moving the document stacking unit up and down in parallel, wherein when the document stacking unit is below a predetermined height, The document loading means is moved up and down by a second control means, and when the document loading means is at a predetermined height or higher, the document loading means is swung by the first control means. Paper equipment.