JPH061476A - Paper feeding device - Google Patents

Abstract

PURPOSE:To favourably carry documents of different sizes set under a single side standard. CONSTITUTION:As a paper feeding roller cooperatively working with separation pieces 6, a plural number of paper feeding rollers 20 with circular arc paper feeding regions 20a and straight non-paper feeding ranges 20b are provided in parallel. When rotation of the paper feeding rollers is started, the paper feeding region 20a of each of the paper feeding rollers 20 synchronously makes contact with the underside of an original and gives carrier force to documents and the documents can be certainly carried without bending produced thereon.

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 in a facsimile machine, a copying machine or the like.

[0002]

2. Description of the Related Art Conventionally, as shown in FIGS.
A document guide 2 that forms a part of a document table for setting
Introducing roller 3 and document retainer 4 for feeding the document 1 set on the document table, paper feed roller 5 provided at the center of the width direction of the apparatus for pulling the document on the document table, and double feeding of the document pressed against it. Separation piece 6 such as a rubber plate for preventing the separation piece 6 and pressing means for pressing the separation piece 6 against the paper feed roller 5 (specifically, a support plate 7 that supports the separation piece 6 and can swing around a support shaft 7a). , A paper feed device equipped with a pressing member 8 which swings around the support shaft 8a and presses the support plate 7, a bar-shaped spring 9 for applying a pressing force to the pressing member 8), and the paper feeding device. A feed roller 11 that conveys a document that has been read, a reading glass 12 that is arranged at a document reading position, a document reading unit (not shown) that is arranged below it, a discharge roller 13 that discharges the document, and a document table. With original that detects the presence of the original placed above There is known a facsimile apparatus including a detection sensor 15, document width detection sensors 16 and 17 for detecting the document width, a reading start position detection sensor 18 that detects that the leading edge of the document has been fed to the feed roller 11. ing. In this facsimile apparatus, when a plurality of originals 1 are set on the original table, the introducing roller 3 feeds them between the paper feeding roller 5 and the separating piece 6, and the paper feeding roller 5 and the separating piece 6 make the originals. 1 is separated and carried in one by one. After the document 1 reaches the feed roller 11, the document is conveyed by the feed roller 11, is read, and is then ejected by the ejection roller 13.

Here, the paper feed roller 5 is a roller having a circular cross section, and the separating piece 6 is constantly pressed against the outer peripheral surface thereof.
When a plurality of originals are drawn between the paper feed roller 5 and the separation piece 6, the paper feed roller 5 gives a conveying force only to the originals in contact with the originals, and the separation pieces 6 give resistance to the other originals. As a result, only the lowermost original was separated and was fed into the feed roller 11. A one-way clutch is provided between the paper feed roller 5 and the drive source. After the leading edge of the original is caught by the feed roller 11 and reaches the reading start position detection sensor 18, the paper feed roller is The drive of 5 is turned off, and the paper feed roller 5 is rotated as the document conveyed by the feed roller 11 travels.

[0004]

However, the conventional sheet feeding device has the following problems.

(1) Since the leading edge of the document 1 set on the document table is only slightly in contact with the outer peripheral surface of the paper feed roller 5, the first conveying force applied to the document by the rotation of the paper feed roller. Is small and paper feeding failure is likely to occur. In particular, if the number of originals set on the original table is increased, the carrying force is lowered, and in order to avoid this, the number of set sheets must be decreased. In addition, it is necessary to use the introduction roller to ensure the feeding.

(2) Since the leading edge of the original is pulled in from the portion in contact with the paper feed roller, when the original is set diagonally, the original is pulled in from the portion in contact with the paper feed roller at the leading edge of the original. The bending of the paper will be further magnified, which will cause a paper jam.

(3) Since the carrying force at the start of feeding is small,
The document is likely to be bent, and particularly when the sheet is fed by a sheet feeding roller not at the center of the document, the document is bent so that good feeding cannot be performed. Therefore, no matter which size original is used, it is necessary to set the original in the center of the apparatus, and it is not possible to set the original based on one side. In order to increase the document conveying force, it is conceivable to provide the sheet feeding rollers in parallel. With this configuration, both sheet feeding rollers may simultaneously apply the document conveying force to the document.
Actually, one of the originals pulls in the original first, and the original is bent, and good conveyance cannot be expected.

(4) The separating piece 6 is constantly pressed against the paper feed roller 5, and therefore, even when the original is being fed by the feed roller 11, the original is pressed against the paper feed roller 5 and, therefore, The frictional force of the separating piece 6 acts on the original document to become a resistance, and the original document is fed by the paper feed roller 5.
Is rotating, and the power required to convey the document is increasing. Further, since the separation piece 6 is rubbed by the document, the separation piece 6 is worn, the life is short, and chatter noise is generated.
Further, when the original has some kind of coating layer on the back surface such as back carbon, the coating layer is rubbed and deteriorated by the separating piece 6, and the separating piece 6 has a material for the coating layer. Adheres and deteriorates.

The present invention has been made in view of the above-mentioned problems, and the number of sets can be increased more than ever before.
It is possible to feed both the original set on one side and the original set at an angle, and it is possible to reduce the power required to convey the original and reduce the abrasion and chattering noise of the separating pieces. An object of the present invention is to provide a sheet feeding device that can feed a document such as back carbon.

[0010]

In order to solve the above problems, the present invention provides a plurality of paper feed rollers in parallel, and further,
Instead of a conventional roller having a circular cross section as the paper feeding roller, a paper feeding region having a long distance from the rotation center is provided on the outer peripheral surface,
A paper feed roller having a non-paper feed area having a short distance from the center of rotation is used, and the pressing force of the separation piece pressed by the pressing means against the paper feed roller is larger than that in the paper feed area in the non-paper feed area of the paper feed roller. It is configured such that it decreases or becomes 0 (the separation piece does not contact the paper feed roller).

The paper feed roller used in the present invention has a sectional shape in which at least a part of a circle is linear, has an elliptical cross section, has an oval cross section, and has a circular cross section eccentric from the center of rotation. And those having elastically deformable protrusions extending from the outer periphery into a blade shape. These paper feed rollers may have the same friction coefficient on the entire outer peripheral surface, but it is preferable that the surface of the non-paper feed area has a lower friction than the surface of the paper feed area. As a means for reducing the friction, a method of applying a low-friction coat to the surface of the paper feed roller, a method of covering the core member with a low friction, or the like can be adopted.

Further, in the present invention, it is preferable to provide an original width detection sensor for detecting the width of the original at a position past the paper feed roller.

[0013]

In the paper feeding device having the above-described structure, the paper feeding roller is normally stopped at the position where the non-paper feeding area faces the separating piece. Therefore, the leading edge of the document set on the document table is It is in a state of being inserted between the separation piece and the non-paper feeding area of the paper feeding roller. During paper feeding, the paper feeding roller rotates from this state, so the paper feeding area of the paper feeding roller simultaneously touches the part of the lower surface of the original that is a little distance from the leading edge of the original and separates. The original is separated and pulled out in cooperation with the piece. For this reason, a plurality of paper feed rollers can simultaneously apply a large conveyance force to the original, the paper can be reliably fed, and good feeding can be performed even when the number of originals set is increased. It is also possible to omit the introduction roller. Further, even if the paper feed roller is arranged at a position deviated from the original, the original can be fed well, and originals of different sizes can be set on one side basis. Further, even when the document is set diagonally, it is possible to feed the document without increasing the bending of the document.

Next, only the lowermost original on the original table is separated and pulled out by the rotation of the paper feed roller, and the original is sent to the downstream feed roller. Is pulled out by the feed roller, and the paper feed roller is rotated by the traveling of the original.However, when the non-paper feeding area is rotated to the position facing the separating piece, the pressing force of the separating piece decreases, so A slippage occurs between them and the paper feed roller stops at that position, after which the document passes between the separating piece and the non-paper feed area of the paper feed roller. Therefore, the pressing force of the separating piece against the original is small, the frictional resistance applied to the original is small, the power required for conveying the original can be reduced, and the abrasion of the separating piece and the generation of chatter noise can be reduced. It is also possible to feed documents such as back carbon. Here, if the friction coefficient of the non-paper feeding area of the paper feeding roller is lowered as described above, slippage easily occurs between the paper feeding roller and the paper feeding roller. This is preferable because it can be surely stopped at a position opposite to and the frictional resistance to the original becomes small. Also,
It is also possible to use a solenoid, a clutch, etc., and forcibly stop the rotation of the paper feed roller at the position where the separation sheet faces the non-paper feed area of the paper feed roller after the leading edge of the document has passed the reading start position detection sensor. good.

As described above, if the document width detection sensor for detecting the width of the document is provided at a position past the paper feed roller, after the document is pulled out from the document table by the paper feed roller,
Its size is detected. Therefore, when originals of different sizes are set on the original table, it is possible to detect the respective sizes of the originals pulled out from the original table.
It is convenient.

[0016]

1 is a schematic perspective view showing a facsimile apparatus equipped with a sheet feeding device according to an embodiment of the present invention, FIG. 2 (a),
(B) is a schematic cross-sectional view showing the sheet feeding device in different operating states, and the same parts as those of the conventional example shown in FIGS. 6 and 7 are designated by the same reference numerals.

In FIGS. 1 and 2, 1 is a document, 2 is a document guide which forms a part of a document table on which the document 1 is set, and 2
Reference numeral a denotes a part of the document guide, which is a paper feed roller 20 described later
It is a document guide portion located beside the. The document table used here has a document guide section (not shown) that guides one side edge of the document at a fixed position, and one side edge of the document is placed along this document guide section. set. Here, a guide member for regulating the other side edge of the document is not necessary, but it is possible to provide a guide member whose position can be adjusted according to the size of the document. In this case, the document bending can be further reduced. be able to. Therefore, when the originals 1 of different sizes are set, the originals are set on the basis of one side thereof, and therefore the position on the opposite side differs depending on the original size.

Reference numeral 3 is an introducing roller for feeding the original 1 set on the original table, and 4 is an original pressing member.
It is provided individually. Reference numeral 20 denotes a paper feed roller that pulls in the original on the original table, and two rollers are also provided in parallel.
The introducing roller 3 and the paper feeding roller 20 are not provided symmetrically with respect to the center of the apparatus, but are provided on one side as shown in the drawing. As a result, even small-sized originals (for example, A5 size) that are set on the basis of one side can be
It can be conveyed by the individual introduction roller 3 and the paper feed roller 20.

Unlike the conventional one, the paper feed roller 20 used here has a shape in which both sides of a circle are linearly cut (that is, D-cut), and the rotation center O is formed on the outer peripheral surface thereof.
The arc-shaped portion 20a having a long distance from the arrow forms a sheet feeding area, and the linear portion 20b having a short distance from the rotation center O forms a non-paper feeding area. In this embodiment, as shown in FIG. 2B, the non-paper feeding area 20b is the paper feeding roller 2
The dimensions are set so that when it is parallel to the document guide portion 2a located on the side of 0, the position is slightly lower than the document guide portion 2a. The outer peripheral surface of the paper feed roller 20 is made of a material having a high friction coefficient. As shown in FIG. 1, two paper feed rollers 20 are fixed in phase with a common shaft 21, and the shaft 21 is connected to a drive source (not shown) via a one-way clutch. There is. In addition,
Alternatively, each paper feed roller 20 may be held on the shaft 21 via a one-way clutch.

Reference numeral 6 denotes a separating piece made of a rubber plate or the like, which is provided so as to be pressed against the paper feed roller 20, and 7 is a supporting plate swingably provided around a support shaft 7a, which holds the separating piece 6. is doing. Reference numeral 8 is a pressing member that is swingable around the support shaft 8a, and 9 is a rod-shaped spring provided so as to apply a clockwise rotating force to the pressing member. This spring 9
Applies a rotational force in the clockwise direction to the pressing member 8, the pressing member 8 imparts a rotational force in the counterclockwise direction about the support shaft 7a to the support plate 7, and the support plate 7 thereby feeds the separation piece 6. It is pressed against the outer peripheral surface of the roller 20. Therefore, the support plate 7, the pressing member 8, the spring 9 and the like constitute pressing means for pressing the separation piece against the sheet feeding roller. Here, the feed roller 2 of the separation piece 6
As shown in FIG. 2A, the pressing force with respect to 0 has such a magnitude that the original can be fed while separating the original when the paper feeding area 20a of the paper feeding roller 20 is in contact with the separating piece 6. 2B, as shown in FIG. 2B, when the non-paper feeding area 20b is located at a position facing the separating piece 6, the separating piece 6 does not contact the non-paper feeding area 20b ( Therefore, the pressing force is set to 0). In order to bring the separation piece 6 into non-contact with the non-paper feeding area 20b,
The spring force of the spring 9 may be reduced,
Alternatively, the swinging of the support plate 7 downward may be stopped by an appropriate stopper.

Numeral 11 is a feed roller for feeding the original having passed through the paper feed roller 20 to the original reading position on the downstream side. Two feed rollers are provided so as to correspond to each paper feed roller 20. 12
Is a document reading glass arranged at the document reading position, 13 is a discharge roller for discharging the document, 15 is a document presence / absence detection sensor for detecting the presence / absence of a document placed on the document table, and 16 and 17 are for detecting the document width. A document width detection sensor. The document width detection sensors 16 and 17 are arranged downstream of the paper feed roller 20. Thus, the document width detection sensors 16 and 17 do not detect the document width when the document is set on the document table, and the width of each document can be detected when the document is pulled out by the paper feed roller 20. 18 is the feed roller 1 at the leading edge of the document
It is a reading start position detection sensor that detects that the sheet has been sent to the first sheet.

The operation of the sheet feeding device configured as described above will be described below. The paper feed roller 20 is shown in FIG.
As shown in (b), the non-paper feeding area 20b is stopped at a position facing the separating piece 6. In this state, multiple originals 1
On the platen. At this time, since there is a gap between the paper feed roller 20 and the separation piece 6, the leading edge of the document can be set by slightly inserting it between the paper feed roller 20 and the separation piece 6.

Next, when the paper is fed, the feed roller 3 is rotated to feed the document 1 and the paper feed roller 20 is rotated, and the leading end portion 20c of the paper feed area 20a of the paper feed roller 20 is rotated.
Touches the lower surface of the original 1 and pushes it up, and moves while pressing it against the upper separating piece 6. As a result, a conveyance force is applied to the original 1 and the original 1 is pulled out. At this time, the paper feed roller 20 contacts not the leading edge of the original document 1 but the lower surface at a position slightly away from the leading edge. Therefore, even if the original document 1 is set to be inclined, the entire width of the paper feeding roller 20 is simultaneously affected by the original document 1.
It is possible to apply a large conveying force to the original 1 by contacting the lower surface thereof, and the two paper feed rollers 20 can contact the original 1 at the same time to provide an conveying force. Therefore, the original can be reliably pulled out, and even if the original is set to be inclined, it can be pulled out without increasing the bending of the original. Further, even when the document size is large (for example, A3 size) and the two paper feed rollers 20 transport the documents at positions deviated in the width direction, the document 1 can be transported well. As a result, even if a document is set on the basis of one side, it can be conveyed without any trouble. Furthermore, even if the number of originals set is large, paper can be fed, and even if the introduction roller 3 is omitted, paper can be fed.

When the paper feed roller 20 rotates to start feeding, as shown in FIG. 2A, the paper feed area 20a of the paper feed roller 20 passes under the separating piece 6, and in the meantime. The original in contact with the paper feed roller 20 is pulled out, and the other originals are prevented from running by the separating piece 6. In this way 1
A document sheet is fed toward the feed roller 11.

After the leading edge of the original 1 is fed to the feed roller 11 and the original is fed by the feed roller 11, the driving of the paper feed roller 20 is cut off, and then the feed roller 11 feeds it. It At this time, when the paper feed area 20a of the paper feed roller 20 is located at a position facing the separation piece 6, the original 1 is pressed against the paper feed area 20a of the paper feed roller by the separation piece 6, so Although the paper feed roller 20 is rotated by the traveling, the paper feed roller 2
When 0 further rotates to reach the position where the non-paper feeding area 20b faces the separating piece 6 as shown in FIG. 2B, the frictional force between the paper feeding roller 20 and the document is almost eliminated. The feed roller 20 stops at that position. After that,
In this state, the document is conveyed by the feed roller 11.
At this time, since the separating piece 6 exerts almost no pressing force on the document being moved, the frictional resistance applied to the document is small. For this reason, the power required to convey the original document becomes smaller than that in the conventional case. Further, the wear generated on the separation piece 6 is extremely reduced, and the life of the separation piece 6 is extended. Further, chattering noise during document transportation is reduced, and a document such as back carbon can be fed.

When one document is completely conveyed by the feed roller 11, the paper feed roller 20 starts to rotate again to feed the next document. By repeating the same operation thereafter, a plurality of documents set on the document table can be fed while separating them one by one.

Next, the operation of the facsimile apparatus shown in FIG. 1 using the paper feeding apparatus having the above-mentioned structure will be described. Paper feed roller 2
When the document is sent by 0, the document width detection sensor 1
Numerals 6 and 17 detect the width of the original, set the reading width by the original reading means, and determine whether the image signal is transmitted as it is or reduced. After that, the original is conveyed by the feed roller 11, is read and transmitted when passing over the original reading glass 12, and then the paper discharge roller 1
Discharged by 3. Here, the document width is equal to the width of the feed roller 2.
Since it is detected after being fed out at 0, the document size can be accurately detected for each document. Since the conventional apparatus shown in FIG. 6 detects the sizes of the originals set on the original table, when originals of different sizes are set at the same time, the original size determination may be wrong, and the recording paper may be wasted. Although unnecessary reduction transmission may be performed, this can be prevented in this embodiment.

In the above embodiment, the non-paper feeding area 20b formed on the paper feeding roller 20 is formed at a position lower than the document guide portion 2a in the state shown in FIG. 6 is configured not to contact the non-paper feeding area, the present invention is not limited to this case, and the separating piece 6 may be configured to contact the non-paper feeding area. Shows an example in that case. The paper feed roller 22 used in the embodiment shown in FIG. 3 has an arcuate paper feed area 22a and a linear non-paper feed area 22b, like the paper feed roller 20 of the embodiment shown in FIG. The distance from the rotation center O of the non-paper feed area 22b is slightly large. Therefore, in the state shown in FIG. 3B, the non-paper feed area 22b is slightly above the document guide portion 2a beside it. Further, in this state, the separating piece 6 is pressed against the non-paper feeding area 22b. However, since the separation piece 6 has moved downward compared to the state shown in FIG. 3A, the pressing force of the spring 9 has decreased,
Therefore, the pressing force of the separation piece 6 against the non-paper feeding area 22b is extremely low. The other structure is the same as that of the embodiment of FIG.

Also in this embodiment, as shown in FIG. 3 (b), the paper feed roller 22 is stopped with its non-paper feed area 22b facing the separating piece 6, and in this state the document is set. Is done. At this time, the sheet feeding roller 22 of the separating piece 6
Since the pressing force against the sheet is low, the leading edge of the document can be set in a state of being inserted between the separation piece 6 and the non-sheet feeding area 22b of the sheet feeding roller 22. Next, the paper feed roller 22 rotates, and the original 1 can be separated and fed while the paper feed area 22a passes under the separating piece 6. Also, the leading edge of the document is fed to the feed roller 11 by the rotation of the paper feed roller 22,
After the drive to the paper feed roller 22 is cut off, the feed roller 1
The paper feed roller 22 is rotated by the document being conveyed by 1. However, when the paper feed roller 22 is rotated to the position shown in FIG. Since the frictional force applied decreases, the paper feed roller 22 stops. After that, the document is continuously conveyed as it is. Thus, similarly to the embodiment of FIG. 2, the original is conveyed with the frictional resistance of the separating piece 6 against the original being small, and the same effect as that of the embodiment of FIG. 1 can be obtained.

When the paper feed roller 22 shown in FIG. 3 is used, even in the state shown in FIG. 3B, the document is separated by the separating piece 6 into the non-paper feed area 22b of the paper feed roller 22.
It has a low pressing force, but it is pressed.
The paper feed roller 22 may give a resistance to a running document and may rotate in some cases. In order to prevent this, it is preferable to reduce the friction coefficient of the surface of the non-paper feeding area 22b of the paper feeding roller 22. Non-paper feed area 22b
In order to reduce the coefficient of friction of No. 2, a low-friction coat may be applied to the surface of the non-paper feed area 22b. It is also effective to cover the non-paper feed area 22b with a low-friction core member. The reduction of the friction coefficient in the non-paper feeding area may be performed on the paper feeding roller 20 shown in FIG.

The paper feed rollers 20 and 2 used in the above embodiments.
2 is the case where two D cuts (linear portions) are formed at symmetrical positions with respect to the central axis, but this D cut is not necessarily limited to two, and may be one.
It may be three or more. Further, the paper feed roller is shown in FIGS.
The shape is not limited to the D-cut shape as shown in FIG. FIG. 4 shows an embodiment thereof, and FIG. 4A shows a sheet feeding roller 24 having an elliptical cross section. In the paper feeding roller 24, the long diameter portion 24a constitutes a paper feeding area and the short diameter portion 24b constitutes a non-paper feeding area. (B) shows the sheet feeding roller 26 having an oval cross section. In the paper feed roller 26, the arcuate portion 26a constitutes a paper feed area and the linear portion 26b constitutes a non-paper feed area. (C) shows a paper feed roller 28 having a circular cross section having a circular cross section eccentric from the rotation center O. The paper feed roller 28 has a rotation center O.
A portion 28a far from the sheet feed area forms a sheet feeding area, and a portion 28b close to the sheet feed area forms a sheet non-feeding area. These paper feed rollers 24, 26,
28 can be used in place of the paper feed roller 20 shown in FIG. 2 or in place of the paper feed roller 22 shown in FIG. Note that these paper feed rollers 24, 26, 28 also have
It is preferable that the surface of the non-paper feed area is coated with a low friction coating or is covered with a core member having a low friction coefficient to reduce the friction coefficient of the surface.

FIG. 5 shows an embodiment in which a paper feed roller 30 having a shape different from the above is used instead of the paper feed roller 20 shown in FIGS. The paper feed roller 30 of this embodiment has a projection 30a extending like a blade on the outer circumference. The protrusion 30a is made of an elastically deformable material such as rubber, and while the paper feed roller 30 rotates, as shown in FIG. It is made long enough to move while deforming. The tip of the projection 30a cooperates with the separating piece 6 to form a paper feeding area for feeding the original while separating the original, and the other portion forms a non-paper feeding area. The configuration other than the paper feed roller 30 is the same as that of the embodiment of FIG.

In the embodiment shown in FIG. 5, FIG.
As shown in FIG. 3, the paper feed roller 30 is stopped with the protrusion 30a positioned below the document guide 2, and the document 1 is set in this state. At this time, since there is a gap between the separation piece 6 and the document guide 2, the front end of the document is separated from the separation piece 6.
It can be set by inserting it deeply below the. Next, when the paper feed roller 30 rotates to feed the paper, the protrusion 30a comes into contact with the lower surface of the original 1 and lifts it.
As shown in FIG. 5 (a), it moves while pressing against the upper separation piece 6. As a result, the document 1 is fed with a conveying force, the document 1 is pulled out, and the separating piece 6 prevents the document from being double-fed. Also in this case, since the protrusion 30a of the paper feed roller 30 simultaneously comes into contact with the lower surface of the document 1 at a position slightly apart from the leading end of the document 1 to pull out the document at the same time, a large conveying force can be given to the document 1. Therefore, it is possible to reliably pull out the original without bending it. When the document fed by the paper feed roller 30 is subsequently conveyed by the feed roller 11, the paper feed roller 30
5 stops at the position shown in FIG. 5B, so that the resistance that the separation piece 6 gives to the document being conveyed is small and the separation piece 6
It is possible to prevent chatter noise. Thus, also in the embodiment using the paper feed roller 30, the same effect as that of the embodiment shown in FIG. 1 can be obtained.

In the embodiment shown in FIG. 1, two paper feed rollers 20 are used, but the present invention is not limited to this, and three or more paper feed rollers may be used. .

[0035]

As is apparent from the above description, the paper feeding device of the present invention serves as a paper feeding roller on the outer peripheral surface of the paper feeding area having a long distance from the center of rotation and a short distance from the center of rotation. A paper feed roller having a non-paper feed area is used, and the pressing force of the separation piece pressed by the pressing means against the paper feed roller is set to be lower in the non-paper feed area of the paper feed roller than in the paper feed area. Therefore, when the original is fed by rotating the paper feed roller, only the lowermost original can be fed while separating the original by the paper feed area and the separating piece. When the sheet is conveyed by the provided feed roller, the non-sheet feeding area of the sheet feeding roller is stopped at a position facing the separating piece, so that the pressing force of the separating piece against the original can be reduced. As a result, the frictional resistance applied to the original document is reduced, the power required to convey the original document can be reduced, the chatter noise can be reduced, and the original document such as back carbon can be fed. Further, since the wear of the separation piece is reduced, the life of the separation piece is extended and the maintenance cycle can be extended.

Further, in the present invention, a plurality of paper feed rollers are provided, and when the paper feed rollers rotate to convey an original, the leading ends of the paper feed areas of the plurality of paper feed rollers are the full width of the paper feed rollers. At the same time, since the document is conveyed by contacting the part a little distance from the leading edge of the document, the document conveying force is extremely large. Therefore, the document is reliably fed and the number of documents set increases. Even if this is done, good paper feeding can be performed, the introduction roller can be omitted, and even if a wide original is set at a biased position or the original is set diagonally, It is possible to feed the paper without expanding the bending, and it is possible to set the original on one side.

If the document width detection sensor is arranged downstream of the paper feed roller, the document size can be judged for each sheet, and waste of recording paper and unnecessary reduction transmission can be prevented.

[Brief description of drawings]

FIG. 1 is a schematic perspective view of a facsimile device including a paper feeding device according to an embodiment of the present invention.

FIG. 2A is a schematic cross-sectional view showing the sheet feeding device in a state in which a sheet feeding roller separates a document while feeding the original; FIG. 2B shows the sheet feeding device in a state in which the sheet feeding roller is stopped. Schematic cross section showing

FIG. 3A is a schematic cross-sectional view showing a sheet feeding device according to another embodiment of the present invention in a state in which a sheet feeding roller separates a document while feeding the sheet feeding device. Schematic cross-sectional view showing the paper roller stopped

FIG. 4A is a schematic side view showing a sheet feeding roller having an elliptical cross section. FIG. 4B is a schematic side view showing a sheet feeding roller having an oval section. FIG. 4C is a schematic side view showing a sheet feeding roller having an eccentric circular section. Side view

5A is a schematic cross-sectional view showing a sheet feeding device according to still another embodiment of the present invention in a state where a sheet feeding roller separates an original, and FIG. 5B shows the sheet feeding device. Schematic sectional view showing the paper feed roller stopped

FIG. 6 is a schematic perspective view of a facsimile device using a conventional paper feeding device.

FIG. 7 is a schematic sectional view of a conventional paper feeding device.

[Description of Reference Signs] 1 original 2 original guide 2a original guide part 3 introduction roller 5, 20, 22, 24, 26, 28, 30 paper feed roller 6 separation piece 7 support plate 8 pressing member 9 spring 11 feed roller 20a, 22a , 24a, 26a, 28a Paper feeding area 20b, 22b, 24b, 26b, 28b Non-paper feeding area 16, 17 Original width detection sensor 30a Protrusion

Claims (2)

[Claims] 1. A plurality of paper feed rollers arranged in parallel so as to pull in a document set on a document table, and a plurality of paper feed rollers provided corresponding to each of the plurality of paper feed rollers to prevent double feeding of documents. And a pressing means for pressing each of the separated pieces against the paper feed roller. The paper feed roller has an outer peripheral surface on which the paper feed area having a long distance from the rotation center and the non-feeding paper having a short distance from the rotation center. And a pressing means for reducing the pressing force of the separation piece with respect to the non-paper feeding area of the paper feeding roller to be lower than the pressing force with respect to the paper feeding area, or to zero. Characteristic paper feeding device. 2. A paper feed roller for drawing in a document set on a document table, a separation piece for pressing the paper feed roller to prevent double feeding of documents, and a pressing means for pressing the separation piece against the paper feed roller. The paper feed roller has a paper feed area on the outer peripheral surface thereof, which has a long distance from the center of rotation, and a non-paper feed area, which has a short distance from the center of rotation. It is characterized in that the pressing force of the separating piece on the non-feeding area of the paper roller is set to be lower than the pressing force on the paper feeding area or is set to 0. Further, the original is placed at a position past the feeding roller. A sheet feeding device, which is provided with a document width detection sensor for detecting the width of the sheet.