JPH09290938A - Automatic document carrying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To appropriately separate and carry a plurality of set document. SOLUTION: In an automatic document carrying device 1, a bent part 3b of a leaf spring 3 is detached from a roller 2 by the prescribed quantity during the waiting time, a contact end part 3a is abutted on the roller 2 at the abutting position A in the document carrying direction forward of the nip position B, and a document 7 is inserted into a gap between the roller 2 and the bent part 3b. When the roller 2 is rotated counterclockwise, the contact end part 3a is moved in the document carrying direction by the friction force with the roller 2, and the bent part 3b is moved in the direction of the roller 2 to press the document 7 against the roller 2. The document 7 is carried to the nip position B by the roller 2, and separated one by one by a pat 5 and carried to the abutting position A. When the tip of the document 7 reaches the abutting position A, the friction force with the leaf spring 3 is reduced, and the bent part 3b of the leaf spring 3 is detached from the roller 2 by its elasticity. When carriage of the final document 7 is completed, the roller 2 is rotated clockwise, and the bent part 3b is largely detached from the roller 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic document feeder, and more particularly, to an automatic document feeder which improves the separation / transportability of a plurality of documents set.

[0002]

2. Description of the Related Art An original reading apparatus, for example, an automatic original feeding apparatus applied to a facsimile apparatus, a scanner apparatus, a copying machine, or the like, and in particular, separating a plurality of originals placed on an original placing table by one roller. In an automatic document feeder for feeding, conventionally, a leaf spring is simply pressed against a roller to feed the original to the nip position between the pad and the roller by the leaf spring, and the original is fed one by one by the pad at the nip position. Separately sent out.

[0003]

However, in such a conventional automatic document feeder, since the leaf spring is simply brought into pressure contact with the roller, the leaf spring is moved to the nip position when the roller starts to rotate. When the original is moved to the side, the later the original becomes, the more difficult it is to be conveyed to the nip position.

In view of the above, according to the first aspect of the invention, a contact portion which comes into contact with the roller at a position in front of the nip position between the separating member for separating the document and the roller, and a position at the rear of the nip position in the document transport direction. By providing a pressing member having a bent portion that separates from and comes into contact with the roller according to the rotation of the roller and presses the original against the roller, a predetermined distance is provided between the bent portion of the pressing member and the roller when the original is inserted. There is a gap, the document is inserted through this gap, and when the roller rotates, the contact portion of the pressing member is pulled by the roller in the rotation direction of the roller, and the bent portion of the pressing member presses the document against the roller, When the original is conveyed to the nip position by the rotation of the roller and the conveyance of the original is completed, the bent portion of the pressing member moves away from the roller to facilitate the insertion of the next original and And its object is to provide an automatic document feeder capable of properly performing transport.

According to a second aspect of the present invention, there is provided a contact member which comes into contact with the roller at a position ahead of the nip position between the roller and the separation member in the document conveying direction and restores the initial contact position, and a position behind the nip position in the document conveying direction. A pressing member that is urged in a direction to come into contact with the roller at a position, the movement of the contact member in the roller direction is restricted, and the contact member comes into contact with and separates from the roller when the position of the contact member changes due to rotation of the roller; When the document is inserted, there is a gap between the pressing member and the roller, and when the document is inserted through this gap and the roller rotates, the contact member is dragged by the frictional force between the roller and the roller. And the position is fluctuated, and according to the position fluctuation of the contact member, the pressing member presses the document against the roller, and the rotation of the roller conveys the document to the nip position.
When the transportation of the original document is completed, the pressing member is separated from the roller according to the restoration of the contact member to the initial contact position, and the next original document can be easily inserted and the original document can be appropriately transported. It is intended to provide an automatic carrier.

According to the third aspect of the present invention, when the conveyance of the final document on the document mounting table is completed, the rollers are reversed so that the clearance between the bent portion of the pressing member and the roller or the clearance between the pressing member and the roller is increased. It is an object of the present invention to provide an automatic document feeder that can more reliably and more largely open the space and can more easily insert a large number of originals next time.

According to a fourth aspect of the invention, when the final document on the document table passes, the roller is rotated at a high speed so that the friction between the contact portion of the pressing member and the roller or between the contact member and the roller is in the dynamic friction region. The automatic document original that makes it possible to make the gap between the bent portion of the pressing member and the roller or the gap between the pressing member and the roller more reliable and larger and to insert the next many originals more easily. It is intended to provide a carrier device.

[0008]

According to a first aspect of the present invention, an apparatus conveys a plurality of originals placed on an original placing table to a nip position by one roller and separates the sheets one by one. In an automatic document feeder for feeding, a separating member that comes into contact with the roller at the nip position to separate the documents one by one, and a contact portion that comes into contact with the roller at a position forward of the nip position in the document transport direction. A bent portion that can come into contact with the original on the roller is provided at a position rearward of the nip position in the original conveying direction, and the bent portion is urged in a direction away from the roller, and the rotation of the roller causes the bent portion to move. The above-mentioned object is achieved by including a pressing member in which the contact portion moves by a predetermined amount and the bent portion comes into contact with and separates from the roller according to the movement of the contact portion.

Here, a pad or the like is used as the separating member, and it comes into contact with the roller at the nip position to separate and convey the originals one by one.

The pressing member is bent into a predetermined shape and has a contact portion and a bent portion, and the contact portion contacts the roller at a position rearward of the roller and the nip position in the original conveyance direction, and the bent portion is positioned more than the nip position. It is possible to contact the roller at the front position in the document conveying direction.

When a document whose roller is not rotating is inserted, the bending portion of the pressing member is separated from the roller by a predetermined amount,
The leading ends of a plurality of documents are inserted into the gap between the bent portion and the roller. When a document is set and inserted, the roller rotates, and when the roller rotates, the contact part of the pressing member moves the bent part in the roller direction due to the friction with the roller, and the document is pressed against the roller and is pressed against the roller. The original document is conveyed to the nip position of the separating member by the rotation of the roller. The documents conveyed to the nip position of the separating member are separated one by one by the separating member and are conveyed to the contact portion of the pressing member.
The contact portion of the pressing member presses the roller and further conveys it. Since the contact portion is urged in the direction away from the roller, when the document is conveyed between the contact portion and the roller, the friction that the contact portion receives is lower than the friction with the roller. Friction, the bent portion separates from the roller, and the double feeding of documents is prevented. Then, when the trailing edge of one original passes through the contact portion and the roller rotates, the next original is separated and conveyed in the same manner as above.

According to the above construction, the contact portion which comes into contact with the roller at a position in front of the document conveying direction with respect to the nip position between the separating member and the roller for separating the document, and the roller at the position behind the nip position with respect to the document conveying direction. Since a pressing member having a bent portion that separates from and comes into contact with the roller according to the rotation and presses the original against the roller is provided, when inserting the original, there is a predetermined gap between the bent portion of the pressing member and the roller. When the original is inserted through this gap and the roller rotates, the contact portion of the pressing member is pulled by the roller in the direction of rotation of the roller, and the bent portion of the pressing member presses the original against the roller, causing the roller to rotate. To convey the original to the nip position,
When the conveyance of the document is completed, the bent portion of the pressing member is separated from the roller, so that the next document can be easily inserted and the document can be properly conveyed.

In the automatic document feeder according to the second aspect of the present invention, a plurality of originals placed on the original placing table are conveyed to the nip position by one roller, and the originals are separated one by one and conveyed. In the automatic document feeder, a separating member that comes into contact with the roller at the nip position and separates the originals one by one, and a roller that comes into contact with the roller at a position forward of the nip position in the document transport direction and rotates the roller. While being moved by a predetermined amount, the contact member is provided with a restoring force to the contact position, and is urged in a direction in which the roller comes in contact with the roller at a position rearward of the nip position in the document transport direction, and comes into contact with the contact member. The above-mentioned object is achieved by including a pressing member that is restricted from moving in the roller direction and that comes into contact with and separates from the roller according to the movement of the contact member.

Here, the contact member comes into contact with the roller at a position ahead of the nip position between the roller and the separation member in the document conveying direction, moves a predetermined amount by the rotation of the roller, and restores the restoring force to the contact position. Have The restoring force may be the elastic force of the contact member itself having a predetermined elasticity, or the elastic force of the elastic member when the contact member is biased by the predetermined elastic member. It may be.

The pressing member is urged in a direction contacting the roller at a position rearward of the nip between the roller and the separating member in the document conveying direction, and its movement in the roller direction is restricted by the contact member, and the contact member is When the roller moves, it moves in the roller direction according to the movement of the contact member.

When the original whose rollers are not rotating is inserted, the pressing member is separated from the roller by a predetermined amount, and a plurality of originals are inserted in the gap between the pressing member and the roller. When a document is set / inserted, the roller rotates, and when the roller rotates, the contact member moves in the roller rotation direction due to friction with the roller, and the pressing member moves in the roller direction according to the movement of the contact member. And press the document against the roller. The original pressed against the roller is conveyed to the nip position of the separation member by the rotation of the roller, and the originals conveyed to the nip position of the separation member are separated one by one by the separation member and then conveyed to the contact member. The contact member presses the roller and conveys it. Since this contact member has a restoring force to the initial contact position, when the document is conveyed between the contact member and the roller, the friction that the contact member receives is lower than the friction with the roller. This causes friction with the original contact position, restores the initial contact position, and the pressing member separates from the roller, thereby preventing double feeding of the original document. After that, when the trailing edge of one document passes through the contact member and the roller rotates, the next document is separated and conveyed in the same manner as described above.

According to the above construction, the contact member that comes into contact with the roller at a position in front of the nip position between the roller and the separating member to restore the original contact position and the contact member that comes back to the initial contact position in the original conveyance direction from the nip position. A pressing member that is urged in the direction of coming into contact with the roller and that is restricted from moving in the roller direction by the contact member and that comes into contact with and separates from the roller when the position of the contact member changes due to rotation of the roller. Therefore, when inserting the original, there is a gap between the pressing member and the roller, and when the original is inserted through this gap and the roller rotates, the contact member is dragged by the rotation of the roller due to the frictional force with the roller. The position of the contact member fluctuates, and the pressing member presses the document against the roller in accordance with the position fluctuation of the contact member, and the rotation of the roller causes the document to be conveyed to the nip position. Touch in response to restoration of the initial contact position of the member, away pressing member from the roller, as well as to facilitate the insertion of the next document, the document transport can be appropriately performed.

In each of the above cases, for example, as described in claim 3, the roller is rotated in the direction opposite to the document transport direction after the transport of the final document on the document mounting table is completed. It may be one.

According to the above construction, when the conveyance of the final document on the document mounting table is completed, the roller is reversed, so that the gap between the bent portion of the pressing member and the roller or the gap between the pressing member and the roller is more reliable. In addition, it is possible to make a larger space, which makes it easier to insert a large number of originals next time.

Further, for example, as described in claim 4, the roller is rotated at a predetermined high speed in the document conveying direction after the conveyance of the final document on the document placing table is completed. May be

According to the above construction, when the final document on the document table passes, the roller is rotated at a high speed, so that the friction between the contact portion of the pressing member and the roller or the contact member and the roller is set as the dynamic friction area and the pressure is applied. The gap between the bent portion of the member and the roller or the gap between the pressing member and the roller can be made more reliable and larger, and the next insertion of a large number of documents can be made easier. .

[0022]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. It should be noted that the embodiments described below are preferred embodiments of the present invention, and therefore, various technically preferable limitations are added. However, the scope of the present invention is not limited to the following description. The embodiments are not limited to these embodiments unless otherwise specified.

FIGS. 1 to 6 are views showing a first embodiment of an automatic document feeder of the present invention. This embodiment is as follows.
A leaf spring having a bent portion is brought into contact with the roller, which corresponds to claims 1, 3, and 4.

FIG. 1 shows a first automatic document feeder of the present invention.
FIG. 9 is a partial side sectional view of the automatic document feeder 1 to which the above embodiment is applied in a standby state. The automatic document feeder 1 is applied to a scanner device, a facsimile device, a copying machine, and the like.

In FIG. 1, an automatic document feeder 1 includes a roller 2 rotatably supported by a bearing or the like (not shown).
The roller 2 is rotationally driven in the counterclockwise and clockwise directions in FIG. 1 by a motor (not shown).

A contact end 3a on the free end side of a leaf spring (pressing member) 3 is in contact with the roller 2, and the leaf spring 3 is
Its base end is fixed to the frame 4 or the like of the automatic document feeder 1. The leaf spring 3 has a bent portion 3b, and the bent portion 3b is located above the roller 2 with a predetermined gap therebetween when the roller 2 is stopped. The leaf spring 3 has a predetermined elastic force, and as shown in FIG. 2, when the roller 2 (indicated by a broken line) is not present, the leaf spring 3 is positioned in the center direction rather than the circumferential position of the roller 2 and is attached to the frame 4. It is installed. Therefore, in the leaf spring 3, the contact end 3a, which is the free end of the leaf spring 3, has a contact position A as shown in FIG.
And is in contact with the roller 2 with a predetermined pressure contact force.

The automatic document feeder 1 is provided with a pad 5, and the pad 5 is attached to a frame or the like (not shown) while being pressed against the roller 2 at the nip position B with a predetermined pressure.

Therefore, the leaf spring 3 has its contact end 3
a is an abutting position A on the front side in the conveyance direction of the original 7 of the roller 2 with respect to the nip position B, which is the abutting position of the pad 5 on the roller 2, and is in contact with the roller 2, and its bent portion 3b is ,
The roller 2 can come into contact with the roller 2 at a position rearward of the nip position B in the conveyance direction of the document 7.

The automatic document feeder 1 is provided with a document placing table 6, and a plurality of documents 7 are placed on the document placing table 6. The original 7 is set with its tip inserted into the gap between the roller 2 and the bent portion 3b of the leaf spring 3, and the original 7 is rotated by the roller 2 and the pad 5 contacting the roller 2. It is conveyed by the leaf spring 3, guided by a guide plate 8 arranged on the downstream side in the conveying direction, and conveyed to the document reading section of the document reading device to which the automatic document feeder 1 is applied.

Further, the automatic document feeder 1 has a document sensor 9 for detecting whether or not the document 7 is set on the document table 6.
The document sensor 9 is, for example, a reflection type optical sensor.

Next, the operation will be described. In the automatic document feeder 1, the bent portion 3b of the leaf spring 3 is rotated according to the rotation of the roller 2.
Is characterized in that the document 7 is brought into and out of contact with the roller 2 to appropriately convey and separate the document 7.

When the automatic document feeder 1 is on standby, that is, when the document 7 is inserted, the bent portion 3b of the leaf spring 3 is
As shown in FIG. 1, the roller 2 is separated from the roller 2 by a predetermined amount, and the contact end portion 3a thereof contacts the roller 2 at the contact position A. Further, the pad 5 is in contact with the roller 2 at a nip position B on the rear side of the contact position A in the conveyance direction of the document 7.

In this state, a plurality of originals 7 are placed on the original placing table 6, and the leading end of the original 7 is the roller 2 and the leaf spring 3.
It is inserted to a position where it abuts on the pad 5 through the gap of the bent portion 3b. At this time, as described above, the leaf spring 3
Since the bent portion 3b is separated from the roller 2 by a predetermined amount, a plurality of originals 7 can be inserted between the bent portion 3b and the roller 2 up to the pad 5 at the tip thereof.

When the document sensor 9 detects the setting of the document 7, the roller 2 is rotated counterclockwise by a motor (not shown) as shown by an arrow in FIG.
When is rotated, the contact end portion 3a of the leaf spring 3 which is in contact with the roller 2 at the contact position A is moved by the frictional force with the roller 2,
As shown by the arrow in FIG. 3, the bent portion 3 of the leaf spring 3 is pulled down in the conveying direction of the original 7, that is, pulled down in FIG.
b moves downward (that is, in the direction of the roller 2) and presses the document 7 against the roller 2.

When the original 7 is pressed against the roller 2 by the bent portion 3b of the leaf spring 3, the original 7 is rotated by the roller 2.
Of the plurality of originals 7, the lowermost original 7 is conveyed to the nip position B between the pad 5 and the roller 2 by the roller 2, and the originals 7 conveyed to the nip position B are separated one by one by the pad 5. And is conveyed to the contact position A between the contact end 3a of the leaf spring 3 and the roller 2.

Further, the original 7 is composed of the roller 2 and the roller 2
The sheet is conveyed by the contact end 3a of the pad 5 and the leaf spring 3 that abut against the sheet, and while being guided by the guide plate 8, is conveyed to the document reading section.

At this time, the leading edge of the original 7 passes through the contact position A between the roller 2 and the contact end 3a of the leaf spring 3, and the contact end 3a of the leaf spring 3 that is in contact with the roller 2 is moved to the original. 7, the contact end 3a of the leaf spring 3 becomes a frictional force between the leaf spring 3 and the original 7, and this frictional force is smaller than the frictional force between the roller 2 and the leaf spring 3. , Due to its elastic force, as shown by the arrow in FIG.
The bent portion 3b moves in a direction away from the roller 2.

Therefore, the bent portion 3b of the leaf spring 3 is separated from the upper surface of the original 7, and the original 7 is prevented from being fed over.

After that, when the conveyance of one original 7 is completed,
When the rear end of the original 7 passes through the contact position A between the contact end 3a of the plate spring 3 and the roller 2, the contact end 3a of the plate spring 3 contacts the roller 2 at the contact position A, and the plate spring 3 Similarly to the above, the frictional force with the roller 2 pulls it down as shown by the arrow in FIG. 3, and the bent portion 3b presses the original 7 against the roller 2.

Therefore, the next original 7 is the same as above.
The bent portion 3b of the leaf spring 3 presses the roller 2 and conveys it.

When the originals 7 are conveyed and separated in sequence and the conveyance of all the originals 7 on the original placing table 6 is completed, the rollers 2 move in the conveying direction of the originals 7 as shown by the arrows in FIG. Are rotationally driven in opposite directions. When the roller 2 is rotated in the direction opposite to the direction in which the original 7 is conveyed, the leaf spring 3 is moved upward in FIG. 5 by the frictional force with the roller 2 at the contact position A, as shown by the arrow in FIG. That is, the bent portion 3b is the roller 2
The bending portion 3b is largely separated from the roller 2 by the biasing force in the direction away from the roller 2. The roller 2 is stopped after being rotated in the opposite direction for a predetermined time.

Therefore, in the automatic document feeder 1, the bent portion 3b of the plate spring 3 is separated from the roller 2 by a predetermined amount.
In the standby state, the next original 7 can be easily inserted into the gap between the roller 2 and the bent portion 3.

When the conveyance of the final original 7 on the original table 6 is completed, the roller 2 may be rotated at a predetermined high speed.

That is, when the original sensor 9 detects that there is no original 7 on the original placing table 6 and the conveyance of the final original 7 is completed, as shown by a double arrow in FIG. , The roller 2 is rotated at a high speed. When the roller 2 is rotated at a high speed, the friction between the leaf spring 3 and the roller 2 at the contact position A shifts to the dynamic friction region, and the friction coefficient decreases. Therefore, the elasticity of the leaf spring 3 causes the leaf spring 3 to move upward as shown by an arrow in FIG. 6, and the bent portion 3b is separated from the roller 2 by a predetermined amount.

As described above, according to this embodiment, the roller 2 is located at the contact position A, which is a position forward of the nip position B between the pad 5 and the roller 2, which is a separating member for separating the document 7, in the document conveying direction. A pressing member having a contact portion 3a that comes into contact with the roller 2 and a bent portion 3b that is located at a position rearward of the nip position B in the document transport direction and that separates from and contacts the roller 2 according to the rotation of the roller 2 and presses the document 7 against the roller 2. Since the leaf spring 3 is provided, when the original 7 is inserted, the bent portion 3b of the leaf spring 3 is bent.
There is a predetermined gap between the roller 2 and the roller 2. When the original 7 is inserted through this gap and the roller 2 rotates, the contact portion 3a of the leaf spring 3 is pulled by the roller 2 in the rotation direction of the roller 2. Then, the bent portion 3b of the leaf spring 3 presses the document 7 against the roller 2, and the rotation of the roller 2 causes the document 7 to be conveyed to the nip position B. When the transportation of the original 7 is completed, the bent portion 3b of the leaf spring 3 is separated from the roller 3, so that the next insertion of the original 7 can be facilitated and the original 7 can be appropriately transported.

When the final document 7 on the document table 6 passes, the roller 2 is reversed, so that the gap between the bent portion 3b of the leaf spring 3 and the roller 2 can be more reliably and larger. It is possible to empty the space, and it is possible to insert a large number of originals 7 next time more easily.

Further, when the final document 7 on the document table 6 passes, the roller 2 is rotated at a high speed, so that the leaf spring 3
By making the friction between the roller 2 and the roller 2 a dynamic friction region, the gap between the bent portion 3b of the leaf spring 3 and the roller 2 can be made more surely and larger, and the insertion of a large number of originals the next time is further improved. It can be done easily.

7 to 11 are views showing a second embodiment of the automatic document feeder according to the present invention. In this embodiment, a position forward of the nip between the roller and the pad in the document feeding direction is shown. A stay that is in contact with the roller and has a restoring force to the initial contact position, and a pressing member that is rotatably supported and that rotates and contacts the roller as the position of the stay changes due to the rotation of the roller. Provided, claim 2, claim 3
And claim 4.

The present embodiment is applied to the same automatic document feeder as the first embodiment,
In the description of the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

In FIG. 7, the automatic document feeder 10 is
A stay (contact member) 11 is in contact with the roller 2,
The stay 11 is a predetermined elastic member, for example, the spring 1.
A restoring force that restores the initial contact position A is given by 2. The fixed end of the spring 12 opposite to the fixed end of the stay 11 is fixed to the frame 4 of the automatic document feeder 1. Therefore, the stay 11 moves by a predetermined amount by the elastic force of the spring 12 and restores to the initial contact position A. The stay 11 may be formed of a member having an elastic force such as a leaf spring. In this case, the stay 11 is restored to the initial contact position A by the elastic force of the leaf spring itself.

The lower surface of the tip of the auxiliary transport plate (pressing member) 13 is in contact with the upper end of the stay 11, and the auxiliary transport plate 1
The base end portion of 3 is attached to the frame 4 and the like so as to be rotatable around the fulcrum portion 13a. The auxiliary transport plate 13 has its free end 13b bent at a predetermined angle, and when rotated in the direction of the roller 2, the lower surface of the free end 13b comes into contact with the roller 2. The auxiliary transport plate 13 is formed of, for example, a material having a predetermined predetermined elastic force such as a leaf spring, and the roller 2
The upper end of the stay 11 is abutted by a predetermined elastic force in the direction. It should be noted that the auxiliary transport plate 13 may not be formed of a material having an elastic force in the auxiliary transport plate 13 itself. In this case, the auxiliary transport plate 13 may be formed of an elastic body such as a spring to form the roller 2. It only has to be biased in the direction.

Therefore, the stay 11 is positioned closer to the roller 2 than the nip position B, which is the contact position of the pad 5 with the roller 2.
Of the original 7 is in contact with the roller 2 at the contact position A on the front side in the transport direction (downstream side in the transport direction), and the auxiliary transport plate 13 is
The roller 2 comes into contact with the roller 2 at a position on the rear side of the roller 2 in the transport direction (upstream side in the transport direction) with respect to the nip position B.

Next, the operation will be described. The automatic document feeder 10 moves the stay 11 in accordance with the rotation of the roller 2 to bring the auxiliary transport plate 13 that comes into contact with the stay 11 into and out of contact with the roller 2 to appropriately carry and separate the document 7. However, there is that characteristic.

When the automatic document feeder 10 stands by, that is, when the document 7 is inserted, the stay 11 is urged by the spring 12 and abuts the roller 2 at a predetermined initial abutment position A. The free end portion 13b of the auxiliary transport plate 13 comes into contact with the upper end of the free end portion 13b of the auxiliary transport plate 13.
Is separated from the roller 2 by a predetermined amount as shown in FIG. Further, the pad 5 is in contact with the roller 2 at a nip position B on the rear side of the original contact position A in the conveyance direction of the original 7.

In this state, a plurality of originals 7 are placed on the original placing table 6, and the leading end of the original 7 passes through the gap between the roller 2 and the free end 13b of the auxiliary transport plate 13 and hits the pad 5. It is inserted to the contact position. At this time, as described above, since the free end portion 13b of the auxiliary transport plate 13 is separated from the roller 2 by a predetermined amount, a plurality of originals 7 reach the pad 5 between the free end portion 13b and the roller 2. Can be easily inserted.

When the document sensor 9 detects the setting of the document 7, the roller 2 is rotated counterclockwise by a motor (not shown) as shown by an arrow in FIG. The stay 11, which is in contact with the roller 2 at the contact position A, is conveyed by the frictional force with the roller 2, as shown by the arrow in FIG.
When the stay 11 is pulled downward, the auxiliary transport plate 13 whose rotation in the counterclockwise direction is restricted at the upper end of the stay 11 is rotated counterclockwise around the fulcrum 13a. When the auxiliary carrier plate 13 is rotated, the free end portion 13b of the auxiliary carrier plate 13 is
The original 7 is pressed against the roller 2.

The original 7 is placed on the free end portion 13 of the auxiliary transport plate 13.
When pressed against the roller 2 by b, the rotating roller 2 causes the lowermost original 7 of the plurality of originals 7 to be conveyed by the roller 2 to the nip position B between the pad 5 and the roller 2, and to the nip position B. The transported original 7 is put on the pad 5.
Then, the sheets are separated one by one and are conveyed to the contact position between the stay 11 and the roller 2.

Further, the original 7 is composed of the roller 2 and the roller 2
The sheet is conveyed by the tip of the pad 5 and the stay 11 that come into contact with the sheet, and while being guided by the guide plate 8, is conveyed to the document reading section.

At this time, when the leading edge of the original 7 passes through the contact position between the roller 2 and the stay 11 and the stay 11 that has been in contact with the roller 2 comes into contact with the original 7, it acts on the stay 11. The force is a frictional force between the stay 11 and the original 7, and this frictional force is smaller than the frictional force between the stay 11 and the roller 2. Therefore, the stay 11 is indicated by an arrow in FIG. 9 due to the elastic force of the spring 12. As described above, the free end portion 13b of the auxiliary transport plate 13 pivotally moves in the direction away from the roller 2 as indicated by the arrow in FIG.

Therefore, the free end portion 1 of the auxiliary carrier plate 13 is
3b is separated from the upper surface of the original 7, and the original 7 is prevented from being fed over.

After that, when the conveyance of one original 7 is completed,
When the trailing edge of the document 7 passes the contact position between the stay 11 and the roller 2, the stay 11 contacts the roller 2 and the stay 11
In the same manner as described above, due to the frictional force with the roller 2, it is pulled down as shown by the arrow in FIG. 8, and the auxiliary transport plate 13 rotates counterclockwise about the fulcrum portion 13a, The free end portion 13b of the auxiliary transport plate 13 presses the document 7 against the roller 2.

Therefore, the next original 7 is the same as above.
The free end portion 13b of the auxiliary transport plate 13 is pressed against the roller 2 and transported.

When the originals 7 are conveyed and separated in sequence and the conveyance of all the originals 7 on the original placing table 6 is completed, the rollers 2 move in the conveying direction of the originals 7 as shown by the arrows in FIG. Are rotationally driven in opposite directions. When the roller 2 is rotated in the direction opposite to the conveying direction of the document 7, the stay 11 moves upward in FIG. 10 by the frictional force with the roller 2, as shown by the arrow in FIG. When moving upward, the auxiliary transport plate 13 in contact with the upper end of the stay 11 rotates clockwise around the fulcrum 13a. When the auxiliary transport plate 13 is rotated clockwise, the free end portion 13b of the auxiliary transport plate 13 is largely separated from the roller 2, and the roller 2 is stopped when it is rotated in the opposite direction for a predetermined time.

Therefore, the automatic document feeder 10 is in a standby state with the free end portion 13b of the auxiliary transport plate 13 separated from the roller 2 by a predetermined amount, and the free end of the roller 2 and the auxiliary transport plate 13 of the next original document 7 is reached. It can be easily inserted into the portion 13b.

When the conveyance of the final original 7 on the original table 6 is completed, the roller 2 may be rotated at a predetermined high speed.

That is, when the original sensor 9 detects that there is no original 7 on the original placing table 6 and the conveyance of the final original 7 is completed, as shown by the double arrow in FIG. , Called high speed). When the roller 2 is rotated at a high speed, the friction between the stay 11 and the roller 2 shifts to the dynamic friction region, and the friction coefficient decreases. Therefore, the stay 11 is moved upward by the elastic force of the spring 12 as shown by the arrow in FIG. 11 to return to the initial position, and the auxiliary carrier plate 13 is moved by the timepiece as shown by the arrow in FIG. By rotating in the direction, the free end portion 13b is separated from the roller 2 by a predetermined amount.

As described above, according to the present embodiment, the roller 2 is brought into contact with the roller 2 at a position ahead of the nip position B between the roller 22 and the pad 5 which is the separating member in the document conveying direction, and is restored to the initial contact position A. The stay 11, which is a contact member, is urged in a direction in which the stay 11 comes in contact with the roller 2 at a position rearward of the nip position B in the document transport direction, and the stay 11 causes the roller 2 to move.
Since the movement of the stay 11 is restricted and the stay 11 is provided with an auxiliary conveying plate 13 that is a pressing member that comes into contact with and separates from the roller 2 when the position of the stay 11 changes due to the rotation of the roller 2, the document 7 is inserted. At times, there is a gap between the stay 11 and the roller 2, and the original 7 is inserted through this gap and the roller 2
When is rotated, the stay 11 is dragged by the rotation of the roller 2 due to the frictional force with the roller 2, and the position of the stay 11 is changed. This stay 1
When the original 7 is conveyed to the nip position B by the rotation of the roller 2, the auxiliary conveying plate 13 presses the original 7 against the roller 2 in accordance with the position variation of No. 1, and when the conveyance of the original 7 is completed, the stay 11 is initially contacted. The auxiliary transport plate 13 separates from the roller 2 in accordance with the restoration to the contact position A. Therefore, the next manuscript 7
Can be easily inserted, and the document 7 can be appropriately conveyed.

When the final document 7 on the document table 6 passes, the roller 2 is reversed, so that the stay 11
By moving the auxiliary transport plate 13 and the roller 2
The gap between and can be made larger and more reliable, and the next insertion of a large number of originals 7 can be made even easier.

Further, when the final document 7 on the document table 6 passes, the roller 2 is rotated at a high speed, so that the stay 1
The friction between the roller 1 and the roller 1 is set to a dynamic friction region, and the stay 11 is moved upward by the urging force of the spring 12, so that the gap between the roller 2 and the auxiliary transport plate 13 that is in contact with the upper end of the stay 11 is more reliably achieved. In addition, a larger space can be provided, and the next insertion of a large number of originals 7 can be further facilitated.

Although the invention made by the inventor has been specifically described based on the preferred embodiments, the invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the invention. It goes without saying that it is possible.

[0071]

According to the automatic document feeder of the first aspect of the present invention, the nip position and the contact portion which comes into contact with the roller at the front position in the document transport direction with respect to the nip position between the roller and the separating member for separating the document. Since a pressing member having a bent portion that is separated from and in contact with the roller according to the rotation of the roller and presses the original against the roller is provided at a position rearward of the original conveyance direction, the bent portion of the pressing member is inserted when the original is inserted. There is a predetermined gap between the roller and the roller, and when the original is inserted through this gap and the roller rotates, the contact portion of the pressing member is pulled in the rotation direction of the roller by the roller, and the bending portion of the pressing member is bent. Presses the document against the roller, conveys the document to the nip position by rotating the roller, and when the document conveyance is completed, the bent part of the pressing member moves away from the roller, facilitating the next document insertion. With the conveyance of the document can be appropriately performed.

According to the automatic document feeder of the second aspect of the present invention, the nip and the contact member that comes into contact with the roller at a position in front of the nip between the roller and the separating member in the document feeding direction and restores to the initial contact position. The roller is urged in a direction to come into contact with the roller at a position rearward of the document conveying direction, and the contact member restricts the movement in the roller direction. When the original is inserted, there is a gap between the pressing member and the roller, and when the original is inserted through the gap and the roller rotates, the contact member contacts the roller. The friction force causes the position to change due to the rotation of the roller, and the pressing member presses the document against the roller according to the position change of the contact member, and the rotation of the roller conveys the document to the nip position. , The conveyance of the document is completed, in accordance with the restoration to the initial contact position of the contact member, with the pressing member away from the roller, to facilitate insertion of the next document,
The document can be properly conveyed.

According to the automatic document feeder of the third aspect of the invention, the rollers are reversed when the transportation of the final document on the document table is completed, so that the gap between the bent portion of the pressing member and the roller or the pressing force is applied. The gap between the member and the roller can be made more surely and larger, and the next insertion of a large number of documents can be made easier.

According to the automatic document feeder of the invention described in claim 4, when the final document on the document table passes, the roller is rotated at a high speed. Therefore, the contact portion of the pressing member and the roller or the contact member and the roller are connected to each other. Is set as a dynamic friction area, the gap between the bent portion of the pressing member and the roller or the gap between the pressing member and the roller can be made more surely and larger. It can be made easier.

[Brief description of drawings]

FIG. 1 is a side sectional view of an essential part of an automatic document feeder according to a first embodiment of the automatic document feeder of the present invention.

FIG. 2 is a side view showing the leaf spring of FIG.

FIG. 3 is a side sectional view of an essential part of the automatic document feeder in a state where a document placed on the document table of FIG. 1 is being transported to a nip position.

FIG. 4 is a diagram showing a state in which one document is completely conveyed by the automatic document feeder of FIG. 1 and a leaf spring is moved upward.

5 is a view showing a state in which the conveyance of the final document by the automatic document feeder of FIG. 1 is completed and the rollers are rotating in the opposite direction.

FIG. 6 is a view showing a state in which the rollers are rotating at a high speed after the conveyance of the final document by the automatic document feeder of FIG. 1 is completed.

FIG. 7 is a side sectional view of an essential part of an automatic document feeder to which the second embodiment of the automatic document feeder of the present invention is applied.

8 is a side sectional view of a main part of the automatic document feeder in a state where a document placed on the document table of FIG. 7 is being transported to a nip position.

9 is a diagram showing a state in which the conveyance of one document is completed by the automatic document feeder of FIG. 7 and a stay and an auxiliary conveyance plate are moved upward.

10 is a view showing a state in which the conveyance of the final document by the automatic document feeder of FIG. 7 is completed and the rollers are rotating in the opposite direction.

11 is a view showing a state in which the rollers are rotating at a high speed after the conveyance of the final document by the automatic document feeder of FIG. 7 is completed.

[Explanation of symbols]

 1 Automatic Document Conveying Device 2 Roller 3 Leaf Spring 3a Contact End 3b Bending Part 4 Frame 5 Pad 6 Document Placement Table 7 Original 8 Guide Plate 9 Original Sensor 10 Automatic Document Conveying Device 11 Stay 12 Spring 13 Auxiliary Conveying Plate 13a Support Point 13b Free end

Claims (4)

[Claims] 1. A plurality of originals placed on an original placing table are conveyed to a nip position by one roller, and
In an automatic document feeder that separates and conveys sheets one by one,
A separating member that comes into contact with the rollers at the nip position to separate the originals one by one, a contact portion that comes into contact with the rollers at a position in front of the nip position in the original conveyance direction, and a rear part in the original conveyance direction from the nip position. A bent portion that can come into contact with the original on the roller at a position, the bent portion is biased in a direction away from the roller, and the contact portion moves by a predetermined amount by the rotation of the roller. An automatic document feeder according to claim 1, further comprising a pressing member in which the bent portion comes into contact with and separates from the roller according to the movement of the contact portion. 2. A plurality of originals placed on an original placing table are conveyed to a nip position by one roller, and
In an automatic document feeder that separates and conveys sheets one by one,
A separating member that comes into contact with the rollers at the nip position to separate the originals one by one, and a roller that is in contact with the rollers at a position ahead of the nip position in the original conveyance direction and moves a predetermined amount by rotation of the rollers, A contact member having a restoring force to the contact position and a direction in which the contact member comes into contact with the roller at a position rearward of the nip position in the document transport direction, and comes into contact with the contact member to move in the roller direction. And a pressing member that comes into contact with and separates from the roller according to the movement of the contact member, and an automatic document feeder. 3. The roller according to claim 1, wherein the roller is rotated in a direction opposite to the original conveying direction after the conveyance of the final original on the original placing table is completed. Automatic document feeder. 4. The roller is rotated at a predetermined high speed in the document conveying direction after the conveyance of the final document on the document table is completed. The described automatic manuscript device.