JPS6326048B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an automatic sheet feeding device that sequentially feeds sheets one by one and reduces feeding errors.

[Technical background of the invention and its problems]

Conventionally, as an automatic sheet feeding device used in facsimile machines, copying machines, etc., a plurality of originals 2 are placed on an inclined original table 1 as shown in FIG.
These originals 2 are placed one on top of the other, and the leading edges of the originals 2 are guided to the contact area between the transport roller 3 and the sorting piece 4. In this state, the transport roller 3 is rotated to separate each original 2 from the upper layer. There is one that transports items in sequence starting from the first item. What is important in configuring such a device is to ensure that the leading edge of each document 2 is always firmly in contact with the contact area between the conveyance roller 3 and the sorting piece 4 in order to prevent so-called misfeed in which the document 2 is not conveyed. The goal is to ensure that the system is introduced in the future. For this reason, in conventional apparatuses, the inclination angle θ of the document table 1 is set to a relatively large angle, for example, about 50° to 60°.
This ensures that the original 2 slides on the original table 1 due to its own weight.

However, with this configuration, the document tray 1
The amount by which the document 2 protrudes upward from the apparatus increases, leading to an increase in the size of the apparatus, and at the same time, it becomes easier for a plurality of original documents 2 to be sent out at once, resulting in a decrease in operational reliability.

Therefore, in the past, the friction coefficient between the conveyance roller 3, the sorting piece 4, and the document 2 was appropriately selected to suppress the feeding of multiple documents 2, or as shown in FIG. A roller 5 is provided to push back the original on the lower layer side, thereby preventing the occurrence of multiple sheet feeding. However, even with this method, multiple sheets of the original are still likely to be fed due to changes in the material of the original 2 or other delicate conditions, and the problem of increasing the size of the apparatus due to the protrusion of the original table 1 has not been solved. Nakatsuta.

[Purpose of the invention]

The present invention provides an automatic sheet feeding device that reduces the occurrence of misfeeds and multiple feeds, improves conveyance stability, and reduces the amount of protrusion of a sheet loading table outside the device, thereby reducing the size and simplicity of the configuration. The purpose is to provide.

[Summary of the invention]

In order to achieve the above object, the present invention provides an auxiliary conveyance roller that comes into contact with the sheet placed on a sheet mounting table so as to move forward and backward, and also drives a control roller with a torque motor to create a space between the control roller and the conveyance roller. Reverse when multiple sheets are interposed,
At other times, the forward rotation is made in response to the rotational movement of the conveyance roller, and a lever is frictionally fixed to the rotating shaft of this control roller, and the swinging movement of this lever when the control roller rotates forward is controlled as described above. This is transmitted to the shaft support mechanism of the auxiliary conveyance roller to bring the auxiliary conveyance roller into contact with the sheet, thereby performing auxiliary conveyance of the sheet.

[Embodiments of the invention]

3 to 6 are diagrams showing the configuration of an automatic sheet feeding apparatus according to an embodiment of the present invention, in which reference numeral 11 indicates a document placement table, 12 a conveyance roller, and 13 a control roller.

The conveyance roller 12 is connected to a motor (not shown) via a shaft 21, and is configured to rotate at a constant speed in the direction of arrow A by this motor. An arm 2 is attached to the shaft 21 of this conveyance roller 12.
One end of the arm 22 is rotatably attached to a shaft, and the other end of the arm 22 is rotatably supported by a shaft 23 and an auxiliary conveyance roller 24 is attached. Further, pulleys 25 and 26 are attached to the shaft 23 of the auxiliary conveyance roller 24 and the shaft 21 of the conveyance roller 12, respectively, as shown in FIG. is set up. This belt 27 transmits the rotational force of the motor for driving the conveyance roller 12 to the shaft 23 of the auxiliary conveyance roller 24 to rotate the auxiliary conveyance roller 24 in the same direction as the conveyance roller 12. Further, a tension spring 28 is stretched between the intermediate portion of the arm 22 and a housing (not shown), and this tension spring 28 causes the auxiliary conveyance roller 24 to
is being pulled upwards. The upper limit of the pull-up position of the auxiliary conveyance roller 24 is determined by the arm 22
A tongue piece 22a protruding from the end on the conveying roller 12 side.
is set by bringing it into contact with the stopper pin 29. Note that a tongue piece 22b that engages with a lever on the control roller 13 side, which will be described later, is provided at the end of the arm 22 on the conveyance roller 12 side.

On the other hand, the control roller 13 is connected to the shaft 3 as shown in FIG.
1 to a drive source 32. This drive source 32 is a motor 32 that generates a driving force in a direction to reverse the control roller 13 within a required torque.
a and a torque limiter 32b.
Here, the torque transmission force of the torque limiter 32b is smaller than the contact friction force between the transport roller 12 and the control roller 13 and the contact friction force between the document and the control roller 13, and is smaller than the contact friction force between the document and the control roller 13. It is set larger than the frictional force. Thus, the control roller 13 is rotated in the direction of arrow B by the driving source 32 when a plurality of originals are interposed between it and the transport roller 12, and on the other hand, when only one original is interposed between it and the transport roller 12, When there is no document present, it rotates in the direction of arrow C in accordance with the rotation of the conveyance roller 12.

Further, a lever 33 having operating pieces 33a and 33b in opposite directions is mounted on the shaft 31 of the control roller 13 with a predetermined frictional force. This frictional shaft attachment structure is, for example, as shown in FIG.
By pivoting the sleeve 34 to which the friction member 34a is attached, bringing the lever 33 into contact with the friction member 34a, and installing the compression spring 36 between the lever 33 and the spring receiver 35, the lever 33
It consists of a so-called friction clutch which is pressed against a friction member 34a with a predetermined frictional force. Lever 3 above
The third working piece 33a is configured to engage with the tongue piece 22b provided on the arm 22 of the conveying roller 12. Also, the other operating piece 3 of the lever 33
3b comes into contact with the stopper pin 38 and the lever 33
This restricts the rotation of in the direction of arrow B'.
Here, the magnitude of the transmission torque in the friction shaft mounting structure of the lever 33 is determined by
The torque is set to be larger than the torque due to the pulling force of the tension spring 28 for pulling up. Note that 1 in the figure
Reference numeral 1a indicates an actuator that detects the presence or absence of a document on the document table 11. As shown in FIG.

With such a configuration, when no original is placed on the original placing table 11, each roller 12,
13 and 24 are stopped, and the auxiliary conveyance roller 24 is in a raised state as shown in FIG.

In this state, if you set a plurality of originals in a bundle on the original placing table 11, the actuator 1 will notify you that this is the case.
1a, the conveyance roller 12 starts normal rotation, and at the same time, the auxiliary conveyance roller 24 starts normal rotation. On the other hand, the actuator 1
1a operates, the motor 3 of the drive source 32
2a also starts to drive, but since the peripheral surface of the control roller 13 is in direct contact with the conveyance roller 12, the control roller 13 does not rotate in the reverse direction due to the action of the torque limiter 32b, but rotates forward in accordance with the rotation of the conveyance roller 12.

Now, when the control roller 13 performs a normal rotation operation, the lever 33 swings in the direction of arrow C' in response to this, and the tongue piece 22b of the arm 22 moves. Then, the arm 22 rotates around the shaft 21 of the conveyance roller 12, and the auxiliary conveyance roller 24 descends in the direction of arrow D. As a result, the auxiliary conveyance roller 24 hits the top layer of the document 15 as shown in FIG. come into contact with Then, the uppermost document 15a is guided to the conveyance roller 12 by the auxiliary conveyance roller 24, and as shown in FIG. It is held and transported. Therefore, when setting the original, the original can be reliably transported even if the leading end is not reliably bitten into the contact area between the transport roller 12 and the control roller 13. In other words, no misfeed occurs.

By the way, if a plurality of originals overlap each other and are guided to the transport roller 12 when the auxiliary transport roller 24 is feeding the original, each of the originals may be bitten by the contact portion between the transport roller 12 and the control roller 13. When the control roller 13 is rotated, the control roller 13 performs a reverse rotation operation. Therefore, among the documents guided by the transport rollers 12, the originals are sent back to the lower document mounting table 11, and only the uppermost document is transported. Thereafter, the control roller 13 repeats forward and reverse rotations little by little until it finishes transporting the uppermost original, thereby preventing the lower original from being transported. Also, at this time, the lever 33 swings in the direction of arrow B' due to the reverse rotation of the control roller 13.
Since the pressing of the tongue piece 22b by the action piece 33a is released and the arm 22 is pulled upward by the tension spring 28, the auxiliary conveyance roller 24 moves the document 1
5 is maintained in a non-contact state. Therefore, when the document 15 is stably guided to the conveyance roller 12, the document is not excessively conveyed by the auxiliary conveyance roller 24.

When the conveyance of the uppermost document is finished, the conveyance roller 12 conveys the next document. At this time, the control roller 13 continues to repeat small forward rotation and reverse rotation operations while blocking the conveyance of the next lower document, thereby allowing only the uppermost document to be conveyed. In addition, when each document is sequentially conveyed while performing forward and reverse operations of the control roller 13, if for some reason the document to be conveyed next does not get caught between the conveyance roller 12 and the control roller 13. In this case, the auxiliary conveyance roller 24 is lowered onto the document 15 by the action of the lever 33 and the arm 22, and auxiliary conveyance of the uppermost document is carried out.

As described above, in the apparatus of this embodiment, the auxiliary transport roller 24 is provided to perform auxiliary transport of the original 15, so that the setting state of the original 15 on the original placing table 11 is uncertain. Also, even if the installation angle of the document placement table 11 is small and the document does not slide stably, the document can always be reliably guided to the transport rollers 12, and as a result, the document can be stably transported without misfeeding. It becomes possible to transport. Further, by reducing the angle of the document placement table 11, the amount of protrusion of the document placement table 11 above the apparatus can be reduced, and as a result, the apparatus can be made compact and simple. Furthermore, in the apparatus of this embodiment, the control roller 13 is driven by a drive source 32 composed of torque limiters 32b and 32a, and the control roller 1
Since the lever 33 is frictionally mounted on the shaft of 3 to control the contact of the auxiliary conveyance roller 24 with the document 15, it is possible to reliably convey the document one by one without having to feed two sheets. Furthermore, the auxiliary conveyance of the document by the aforementioned auxiliary conveyance roller 24 can be carried out efficiently and stably.

Note that the present invention is not limited to the above embodiments. For example, the drive source for driving the control roller 13 may be composed of a torque motor itself instead of the motor and torque limiter of the above embodiment. Furthermore, in the embodiment described above, the auxiliary conveyance roller 24 is driven by the motor for driving the conveyance roller 12, but it may be driven by a completely separate motor. Furthermore, when the drive source is composed of a motor and a torque limiter, this motor can also be used as a motor for driving the conveyance roller. In addition, the configuration of the interlocking mechanism for bringing the auxiliary conveyance roller into contact with the document can be modified in various ways without departing from the gist of the present invention.

〔Effect of the invention〕

The present invention provides an auxiliary conveyance roller that comes into contact with the sheet placed on a sheet mounting table so as to be able to move forward and backward, and drives the control roller with a drive source that causes slippage under a load exceeding a set torque so that the control roller can be moved between the sheet and the conveyance roller. When a plurality of sheets are interposed in the conveyance roller, the rotation is reversed, and at other times, the conveyance roller is rotated in the forward direction in response to the rotational movement of the conveyance roller. The swinging motion of the lever during forward rotation is transmitted to the shaft support mechanism of the auxiliary conveyance roller to bring the auxiliary conveyance roller into contact with the sheet, thereby performing auxiliary conveyance of the sheet.

Therefore, according to the present invention, it is possible to improve conveyance stability by reducing the occurrence of misfeeds and multiple feeds, and to reduce the amount of protrusion of the sheet loading table outside the apparatus, thereby simplifying the configuration. A scaleable automatic sheet feeding device can be provided.

[Brief explanation of drawings]

1 and 2 are side views showing the schematic configuration of a conventional automatic sheet feeding device, and FIG.
6 to 6 are diagrams for explaining one embodiment of the present invention, in which FIG. 3 is a side view of an automatic sheet feeding device, FIG. 4 is a sectional view taken along the - arrow in FIG. 3, and FIG. FIG. 6 is a cross-sectional view showing the drive mechanism of the control roller, and FIG. 6 is a schematic diagram showing another state of FIG. 3. 11... Document placement table, 12... Conveyance roller, 1
3...Control roller, 15...Document, 21, 23,
31...Axis, 22...Arm, 22a, 22b...
... Tongue piece, 24 ... Auxiliary conveyance roller, 25, 26 ...
...Pulley, 27...Belt, 28...Tension spring,
29, 38... Stopper pin, 32... Drive source,
32a...Motor, 32b...Torque limiter,
33... Lever, 33a, 33b... Action piece.

Claims (1)

[Claims] 1. A sheet loading table, a conveying roller disposed near the sheet conveying end of the sheet loading table that rotates normally in the same direction as the sheet conveying direction, and a conveying roller that rotates in the same direction as the conveying roller. An auxiliary conveyance roller that comes into contact with the sheet set on the sheet mounting table so as to move forward and backward through a shaft stop mechanism and guides the sheet to the conveyance roller, and is connected to a drive source that causes slippage under a load exceeding a set torque. When the circumferential surface contacts the circumferential surface of the conveyance roller and a plurality of sheets are interposed between the conveyance roller and the conveyance roller, it rotates in the opposite direction to the conveyance direction of the sheets, and otherwise rotates forward in response to the conveyance roller. a control roller that rotates, and a lever that is frictionally fixed to the rotating shaft of the control roller, and when the control roller rotates forward, the swinging motion of this lever is transmitted to the shaft support mechanism of the auxiliary conveyance roller, so that the auxiliary conveyance roller An automatic sheet feeding device characterized by comprising an interlocking mechanism for bringing the sheet into contact with the sheet. 2. The auxiliary conveyance roller operates in conjunction with the rotational movement of the conveyance roller.
Automatic sheet feeding device as described in section.