JPH061477A - Paper feeding device - Google Patents

Abstract

PURPOSE:To certainly feed document set on document feed tray, prevent generation of chattering noise of a separative piece and lengthen the life span of the separative piece. CONSTITUTION:As a paper feeding roller cooperatively working with a separative piece 6, a paper feeding roller 20 with a circular arc paper feeding region 20a and a straight non-paper feeding region 20b is used, and it is constituted so that while the paper feeding roller 20 rotates, feeding and separation of an original is carried out at the time when the paper feeding region 20a passes the separative piece 6, and at the time when the document is delivered to a delivery roller 11 on the downstream and is carried by the delivery roller 11, the non-paper feeding region 20b of the paper feeding roller 20 stops at a position facing the separative piece 6 and frictional force of the separative piece 6 against the original is lowered. Additionally, to prevent overlapped delivery of the document at the time when the frictional force of the separative piece 6 against the original is lowered, an auxiliary separative means is provided.

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. 30 and 31, a support surface 2a forming a part of a document table on which a document 1 is set, and an inclined guide surface 2b inclined downward with respect to the support surface 2a.
Document guide 2 having a document and document 1 set on the document table
The feed-in roller 3 and the document retainer 4 for feeding the document, the paper feed roller 5 provided in the center of the apparatus in the width direction of the document table so as to pull in the document on the document table, and the rubber plate or the like pressed against the feed roller 5 to prevent the document from being double fed. The piece 6 and the separated piece 6 are attached to the sheet feeding roller 5.
Pressing means (specifically, a support plate 7 that supports the separation piece 6 and can swing about a support shaft 7a; a pressing member 8 that swings about the support shaft 8a and presses the support plate 7; A paper feeding device including a bar-shaped spring 9 for applying a pressing force to the pressing member 8), an upper surface guide 10 arranged to face the document guide 2, and a document fed by the paper feeding device. A feed roller 11 for conveying, a reading glass 12 arranged at a document reading position, a document reading means (not shown) arranged below it, a discharge roller 13 for discharging a document, and a document set on a document table. A document presence / absence detection sensor 15 for detecting the presence or absence of a document, document width detection sensors 16 and 17 for detecting the document width, and a reading start position detection sensor 18 for detecting that the leading edge of the document has been fed to the feed roller 11. Facsimile equipment equipped with It is known. In this facsimile apparatus, when a plurality of originals 1 are set on the original table, the introduction 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. One to one
Separate and put 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) The separation piece 6 is constantly pressed against the paper feed roller 5, and therefore, even when the document is being fed by the feed roller 11, the document 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 may be generated depending on the type of the document. Further, when the original has some coating layer on the back surface such as back carbon, the coating layer is rubbed by the separation piece 6 and deteriorates.
The material of the coating layer adheres to the separation piece 6 and deteriorates.

The present invention has been made in view of the above problems, and the number of sets can be increased more than ever before.
Even if the original is set diagonally, it can be fed without expanding the bend, and the power required for conveying the original can be reduced, and the abrasion of the separation piece and the occurrence of chatter noise can be reduced. An object of the present invention is to provide a paper feeding device that can feed a document such as back carbon.

[0009]

In order to solve the above-mentioned problems, the present invention replaces a conventional roller having a circular cross section as a paper feeding roller with a paper feeding area having a long distance from the center of rotation on the outer peripheral surface. , Using a paper feed roller having a non-paper feed area having a short distance from the center of rotation, and the pressing force of the separation piece pressed by the pressing means against the paper feed roller is higher than that in the paper feed area in the non-paper feed area of the paper feed roller. Is also reduced or becomes 0 (the separation piece does not contact the paper feed roller).

Further, according to the present invention, in order to compensate for the decrease in the separating force of the separating piece when the non-feeding area of the sheet feeding roller faces the separating piece, the auxiliary separating for preventing the double feeding of the originals. It is also characterized in that means are provided. Examples of the auxiliary separating means include those shown below.

(1) A leaf spring mounted on both sides of the paper feed roller on the support surface of the document guide so as to extend above the inclined guide surface (claim 1).

(2) A film attached to both sides of the paper feed roller on the supporting surface of the document guide so as to extend above the inclined guide surface (claim 2).

(3) A sponge attached to both sides of the paper feed roller on an upper surface guide provided opposite to the document guide (claim 3).

(4) On both sides of the paper feed roller, a film attached to the support surface of the document guide so as to extend above the inclined guide surface, and a top guide provided opposite the document guide of the paper feed roller. A leaf spring having claws attached to both ends thereof (claim 4).

(5) On both sides of the paper feed roller, the film is attached to the supporting surface of the document guide so as to extend above the inclined guide surface, and the paper feed roller is provided on the upper surface guide provided opposite to the document guide. Rubber plates attached to both sides of the (Claim 5).

(6) An auxiliary separating piece which is provided so as to be in contact with the inclined guide surfaces of the document guides on both sides of the paper feeding roller and which moves up and down in conjunction with the separating piece pressed against the paper feeding roller (claim 6).

(7) Claws provided on both sides of the paper feed roller so as to be in contact with the inclined guide surfaces of the document guide, and which move up and down in conjunction with the separating piece pressed against the paper feed roller (claim 7).

(8) A circular ring provided on both sides or one side of the paper feeding roller on the same axis as the paper feeding roller, and an auxiliary separating piece provided so as to be pressed against the circular ring (claim 8).

(9) An arcuate convex portion provided in the vicinity of the sheet feeding roller, and an auxiliary separating piece provided so as to be pressed against the convex portion (claim 9).

[0020]

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, the feeding of the originals is ensured, and even if the number of the set originals is increased, good feeding can be performed, and the introduction roller can be omitted. Further, even when the document is set diagonally, it is possible to feed the document without expanding the bending of the document.

Then, only the lowermost original on the platen 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.

As described above, when the non-paper feeding area of the paper feeding roller comes to the position facing the separating piece, the paper feeding roller stops at that position, and the original conveyed by the feed roller becomes the non-paper feeding area. Although the paper passes between the separating pieces, at this time, the pressing force of the separating pieces is reduced, so that the separating force for the originals is reduced, and there is a possibility that the originals are double fed. Therefore, the auxiliary separating means prevents passage of the second and subsequent originals to prevent double feeding. The separating action of the auxiliary separating means having the configurations shown in (1) to (9) above is as follows.

(1) The leaf springs attached to the supporting surfaces of the document guides on both sides of the paper feed roller (claim 1) give unevenness to the document passing therethrough, so that the document bends. Therefore, the originals are less likely to bend downward, the leading edges of the second and subsequent originals are less likely to be drawn between the paper feed roller and the separating piece, and double feeding is prevented.

(2) The film attached to the supporting surface of the document guide on both sides of the paper feed roller (Claim 2) also imparts unevenness to the document in the same manner as the leaf springs described above, and the document is stiffened so that it is not heavy. Can be prevented from being sent.

(3) If a sponge is provided on the upper surface guide provided so as to face the document guide (claim 3), the tip of the second and subsequent documents will hit and be caught by the sponge. Therefore, the second and subsequent originals do not proceed any further, and the double feeding is prevented.

(4) If the film is attached to the supporting surface of the document guide on both sides of the paper feed roller and the top guide is provided with a leaf spring having a claw at the tip (claim 4), the film passes over it. The original to be bent is provided with a ridge due to unevenness, and the claws at the tip of the leaf spring catch the tips of the second and subsequent originals to prevent the document from advancing further, thereby preventing double feeding of the originals.

(5) If a film is attached to the supporting surfaces of the document guides on both sides of the paper feed roller and a rubber plate is attached to the upper guides (claim 5), the original document passing over the film may have unevenness. The user sits down, so that the leading edge of the second and subsequent documents hits the rubber plate. As a result, the blocking force of the rubber plate acts on the second and subsequent originals, and the double feeding of the originals can be prevented.

(6) If auxiliary separation pieces are provided on both sides of the paper feed roller so as to be in contact with the inclined guide surfaces of the document guide, and the auxiliary separation pieces are moved up and down in conjunction with the separation pieces pressed against the paper feed roller ( According to a sixth aspect of the present invention, when the paper feeding area of the paper feeding roller passes under the separating piece to separate and feed the original, the auxiliary separating piece is separated upward from the original guide, and resists the passing original. Although not given, when the non-feeding area of the paper feed roller is stopped below the separating piece, the auxiliary separating piece is pressed against the document guide and gives resistance to the document passing between them. As a result, it is possible to prevent double feeding of documents.

(7) If the pawls are provided on both sides of the paper feed roller so that they can contact the inclined guide surface of the document guide, and the pawls are moved up and down in conjunction with the separating piece pressed against the paper feed roller ( According to claim 7), when the paper feeding area of the paper feeding roller passes under the separating piece to separate and feed the original, the claw is apart from the original guide and does not interfere with the passing original. When the non-feed area of the feed roller stops under the separating piece, the pawl is pressed against the document guide,
The leading edge of the second and subsequent documents is caught by the nail, and further progress is blocked. As a result, it is possible to prevent double feeding of documents.

(8) If a circular ring is provided on both sides or one side of the paper feeding roller on the same axis as the paper feeding roller, and an auxiliary separating piece is provided so as to be able to be pressed against the circular ring (claim 8), The auxiliary separating piece imparts resistance to the original to be fed, and double feeding can be prevented.

(9) When an arcuate convex portion is provided near the paper feed roller and the auxiliary separating piece is provided so as to be able to be pressed against the convex portion (claim 9), the convex portion and the auxiliary separating piece are separated from each other. The auxiliary separating piece gives resistance to the document passing therethrough, and double feeding can be prevented.

[0032]

Embodiments of the present invention shown in the drawings will be described in detail below. FIG. 1 is a schematic perspective view showing a facsimile apparatus equipped with a sheet feeding device according to an embodiment of the invention described in claim 1 of the present application, and FIGS. 2A and 2B show a sheet feeding roller of the sheet feeding device. FIG. 3 is a schematic cross-sectional view showing parts in different operating states,
The same parts as those of the conventional example shown in FIGS. 30 and 31 are designated by the same reference numerals.

In FIGS. 1 and 2, 1 is a document, 2 is a document guide, and a support surface 2a forming a part of a document table on which the document 1 is set, and an inclination inclined downward with respect to the support surface 2a. It has a guide surface 2b. Reference numeral 3 is an introducing roller for feeding the original 1 set on the original table, and 4 is an original pressing member. Reference numeral 20 denotes a paper feed roller that pulls in a document on the document table, and is arranged in a hole formed at the center of the document guide 2.

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. At least the paper feed region 20a of the outer peripheral surface of the paper feed roller 20 is made of a material having a high friction coefficient similar to that of a conventional paper feed roller. The non-paper feeding area 20b may be configured to have the same friction coefficient as the paper feeding area 20a, but it is preferable to set the friction coefficient lower than that. In order to reduce the friction coefficient of the non-paper feeding area 20b, it is preferable to adopt a method of applying a low friction coating on the surface of the non-paper feeding area 20b, a method of covering the non-paper feeding area 20b with a low friction core member, or the like. .

The paper feed roller 20 is fixed to a shaft 21, and the shaft 21 is connected to a drive source (not shown) via a one-way clutch. Instead of this, the paper feed roller 20 may be held by 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 which is swingably provided around a support shaft 7a, and holds the separating piece 6. In addition, a part for pressing the separating piece 6 is provided. 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, and the pressing member 8 is supported by the support plate 7
, A counterclockwise rotational force about the support shaft 7a is applied to
The support plate 7 thereby presses the separation piece 6 against the outer peripheral surface of the paper feed 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 pressing force of the separating piece 6 against the sheet feeding roller 20 is, as shown in FIG.
When the paper feed area 20a of 0 is in contact with the separation piece 6,
The size is set so that the document can be fed while being separated, and as shown in FIG. 2B, when the non-paper feeding region 20b is positioned to face the separating piece 6, the document is separated. The pressing force of the strip 6 against the non-paper feeding area 20b is set to be significantly reduced.

Reference numeral 10 is an upper surface guide provided corresponding to the original guide 2, 11 is a feed roller for conveying the original having passed through the paper feed roller 20 to a downstream original reading position, and 12 is an original placed at the original reading position. A reading glass, 13 a discharge roller for discharging a document, 15 a document presence / absence detection sensor for detecting the presence / absence of a document set on a document table, 16/17 a document width detection sensor for detecting a document width, and 18 a document leading edge. Is a reading start position detection sensor for detecting that the paper has been fed to the feed roller 11.

Reference numeral 22 denotes a leaf spring which is attached to both sides of the paper feed roller 20 on the supporting surface 2a of the document guide 2 so as to extend above the inclined guide surface 2b, and an auxiliary separating means for preventing double feeding of documents. Make up.

The operation of the sheet feeding device configured as described above will be described below. In order to make the description easier to understand, first, the sheet feeding operation by the sheet feeding roller 20 will be described assuming that the leaf spring 22 constituting the auxiliary separating unit is not provided.

As shown in FIG. 2B, the paper feed roller 20 is stopped at a position where the non-paper feed area 20b faces the separating piece 6. In this state, a plurality of documents 1 are set on the document table. At this time, since the pressing force of the separating piece 6 against the paper feed roller 20 is low, the leading edge of the original is fed to the paper feed roller 20.
It can be set by inserting a little between it and the separation piece 6.

Next, when the paper is fed, the feed roller 3 rotates to feed the document 1 and the paper feed roller 20 rotates, 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 of the original 1. For this reason, the original can be reliably pulled out,
Further, even if the original is set to be inclined, it can be pulled out without increasing the bending of the original. 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 paper feeding, the paper feed area 20a of the paper feed roller 20 passes under the separating piece 6 as shown in FIG. 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 document 1 is fed to the feed roller 11 and the original document is conveyed by the feed roller 11, the driving of the paper feed roller 20 is cut off, and thereafter the document is conveyed by the feed roller 11. 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 original becomes small. The feed roller 20 stops at that position. After that, the document is conveyed by the feed roller 11 in this state. At this time,
Since the separating piece 6 does not exert a 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. Note that, as described above, it is preferable to reduce the friction coefficient of the non-paper feeding area 20b, because the frictional resistance against the original becomes small.

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

In the above embodiment, as shown in FIG. 2B, the non-paper feeding area 20b of the paper feeding roller 20 is separated by the separating piece 6.
Although the separation piece 6 is pressed against the non-paper feed area 20b in a state of facing the sheet, the present invention is not limited to this case, and the separation piece 6 is pressed in the non-paper feed area 20b.
It is also possible to configure so that they do not contact. FIG. 3 shows an embodiment in that case. The paper feed roller 23 used in the embodiment shown in FIG. 3 has an arcuate paper feed area 23a and a linear non-paper feed area 23b, like the paper feed roller 20 of the embodiment shown in FIG. The non-paper feed area 23
The distance from the rotation center O of b is slightly smaller. Therefore, when the state shown in FIG.
3b is located slightly lower than the inclined guide surface 2b of the document guide 2. Further, in this state, the support plate 7 is appropriately lowered so that the separating piece 6 is not in contact with the non-paper feeding area 23b (the pressing force is 0) (not shown).
Have been blocked by. The other structure is the same as that of the embodiment of FIG.

Also in this embodiment, as shown in FIG. 3B, the paper feed roller 23 is stopped with its non-paper feed area 23b facing the separating piece 6, and in this state the document is set. Is done. At this time, the separating piece 6 is attached to the paper feeding roller 23.
Since they are not in contact with each other, the leading edge of the document can be set in a state of being inserted between the separation piece 6 and the non-paper feeding area 23b of the paper feeding roller 23. Next, the paper feed roller 23 rotates, and the original 1 can be separated and fed while the paper feed area 23 a 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 23,
After the drive to the paper feed roller 23 is cut off, the feed roller 1
Although the paper feed roller 23 is rotated by the document being conveyed by 1, the pressing force of the separation piece 6 against the paper feed roller 23 disappears when the paper is fed to the position shown in FIG. Since the frictional force decreases, the paper feed roller 23 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 23 shown in FIG. 3 is used, in the state shown in FIG. 3 (b), the original cannot be pressed against the non-paper feed area 23b of the paper feed roller 23. The paper feed roller 23 hardly gives resistance to the running document, and therefore the friction coefficient of the surface of the non-paper feed area 23b of the paper feed roller 23 does not have to be reduced.

Paper feed rollers 20 and 2 used in the above embodiments
3 is a 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.

As described above, by using the paper feeding roller having the paper feeding area and the non-paper feeding area (for example, the paper feeding roller 20 shown in FIGS. 1 and 2), the original feeding roller 1 is used.
While the sheet is being conveyed at 1, the sheet feeding roller is stopped at a position where the non-sheet feeding area faces the separating piece 6, whereby the frictional resistance against the document being conveyed is reduced, and various advantages are obtained. However, at this time, as a result of the frictional resistance of the separation piece with respect to the original being reduced, the original on the original pulled out by the feed roller 11 may pass between the paper feed roller and the separation piece, and may be double-fed. . Therefore, in the embodiment shown in FIG. 1, a leaf spring 22 is provided as an auxiliary separating means for preventing the double feeding. The operation of the leaf spring 22 that constitutes the auxiliary separating means will be described below.

As shown in FIGS. 5 and 6, the leaf spring 22 is provided so that its tip extends above the inclined guide surface 2b. Therefore, the leaf spring 22 is provided for the original 1a passing therethrough.
Gives unevenness. Original 1a located at the bottom
Is conveyed over the leaf spring 22 by the sheet feeding force of the sheet feeding roller 20 and the separating piece 6, and then conveyed by the feed roller 11. At this time, the leaf spring 22 is bent to a certain extent by the original 1a, so that the original 1a is not prevented from being conveyed. The lowermost original 1a is the feed roller 11
As described above, the sheet feeding roller 20 is stopped at the position where the non-sheet feeding area 20b faces the separation piece 6 while being conveyed by the sheet feeding roller 20. While the document 1a is being pulled out by the feed roller 11 in this state, the document 1 located above the document 1a
The originals 1b and 1c are also pulled by the original 1a, but when the originals 1b and 1c on the original 1a come on the leaf springs 22, the leaf springs 22 make unevenness, which makes the originals larger and less likely to bend downward. And will be pressed against the separating piece 6. As a result, the originals 1b and 1c other than the pulled-out original 1a are separated from the separation piece 6 and the paper feed roller 2.
It becomes difficult to pass through the non-paper feeding area 20b of 0, and the double feeding of the document is prevented.

Although the leaf spring 22 is used as the auxiliary separating means in the above embodiment, an elastic film can be used instead of the leaf spring 22. FIG. 7 shows an embodiment (embodiment of the invention of claim 2) in that case, in which a pair of films 22A are provided on both sides of the sheet feeding roller 20 in place of the leaf springs. This film 22A
Is a resin film with a thickness of about 0.1 mm and has appropriate elasticity. This film 22A also has the same effect as the leaf spring 22 of FIG. Since the film 22A has a smaller elasticity than the leaf spring 22, the film 22A has a wide width to secure the necessary elasticity.

The embodiment in which the original is made uneven by using the leaf spring 22 or the film 22A so as to prevent the double feeding of the original has been described above. The auxiliary separating means used for preventing the double feeding of the original is this. Various structures other than the leaf spring 22 or the film 22A can be used. The example will be described below.

FIG. 8 and FIG. 9 show an embodiment of the invention described in claim 3 of the present application. As an auxiliary separating means, a sponge 30 is provided on the upper surface guide 10 so as to be positioned on both sides of the paper feed roller 20. Is provided. In this embodiment, when the lowermost original is being conveyed by the feed roller 11 in a state where the paper feed roller 20 is stopped at a position where the non-paper feed area 20b faces the separating piece 6, the original 2 is fed by the feed roller 11. When the document after the first one is about to be pulled out, the tip of the document hits the sponge 30. This sponge 3
0 has a rough surface, so the leading edge of the document is caught, and further entry is prevented. Thus, document double feeding is prevented.

Next, FIGS. 10 and 11 show an embodiment of the invention described in claim 4 of the present application.
A film 22A is attached to the support surface 2a of the document guide 2 on both sides of the document so that its tip extends above the inclined guide surface 2b, and a leaf spring 32 having a claw 32a at its tip is attached to the top guide 10. There is. This claw 32a
Are arranged so as to extend slightly ahead of the front end of the film 22A. In this embodiment, the original document through which the film 22A passes is made uneven so that the original document can be stretched.
It is difficult to bend downward, and the second and subsequent documents are
When the document is moving and is moved forward, the tip of the document strikes the claw 32a of the leaf spring 32. Therefore, the second and subsequent originals are hooked by the claws 32a of the leaf spring 32 and are prevented from further traveling. Thus, double feeding of documents is prevented.

12 and 13 show an embodiment of the invention described in claim 5 of the present application, in which the film 22A guides the leading end of the film 22A on the support surface 2a of the document guide 2 on both sides of the paper feed roller 20. A rubber plate 34 is attached so as to extend above the surface 2b, and a rubber plate 34 is attached to the upper surface guide 10 at a portion located at the leading end of the film 22A. In this embodiment, the original document through which the film 22A passes is made uneven so that the original document is not bent and hard to bend downward.
In addition, when the second and subsequent originals are dragged by the moving originals and moved forward, the tip end thereof strikes the rubber plate 34. Therefore, the second and subsequent originals are prevented from further traveling by the rubber plate 34. Thus, double feeding of documents is prevented.

14 and 15 to 17 show an embodiment of the invention described in claim 6. In this embodiment, the separating piece 6A provided so as to be pressed against the paper feed roller 20 is made wider than the separating piece 6 of the other embodiments, and contacts the paper feed roller 20. Central part 6a
Auxiliary separating pieces 6b capable of contacting the inclined guide surface 2b of the document guide 2 are provided on both sides of. In this example,
As shown in FIG. 15, after the document 1 is set, the paper feed roller 20 rotates to separate and feed the document 1 one by one. As shown in FIG. Area 2
0a comes into contact with the separating pieces 6A, and when the originals 1 are separated and fed one by one, the paper feed roller 20 pushes the separating pieces 6A upward, so that the auxiliary separating pieces 6b on both sides are It is separated from the inclined guide surface 2b of the document guide 2 and does not interfere with the document passing therethrough. However, as shown in FIG. 17, the paper feed roller 20 has a non-paper feed area 20b.
When stopping at the position facing the separation piece 6A, the separation piece 6A
Since A is descending downward, the auxiliary separating piece 6b presses the document against the inclined guide surface 2b of the document guide 2. For this reason, when the second and subsequent documents are going to pass, the auxiliary separating piece 6b gives resistance to the document and blocks the passage.
As a result, double feeding of documents is prevented.

In the embodiment of FIG. 14, the auxiliary separating piece 6b is used.
Is formed integrally with the separation piece 6A, the auxiliary separation piece 6
b may be a separate component from the separating piece that contacts the paper feed roller 20. However, even in that case, the auxiliary separation piece 6b is directly connected to the separation piece so as to move up and down together with the separation piece which comes into contact with the sheet feeding roller 20, or is connected to the support plate 7 holding the separation piece. It is necessary to keep it. 18,
19 to 21 show an embodiment of the invention described in claim 7. In this embodiment, a support plate 7 for holding the separation piece 6 provided so as to be pressed against the paper feed roller 20.
Claws 36 that can contact the inclined guide surface 2b of the document guide 2 are provided on both sides of the claw 36, and the claws 36 are moved up and down in conjunction with the separation piece 6. According to this configuration, as shown in FIG. 19, after the original 1 is set, the paper feed roller 20 rotates to separate the originals 1 and feed them one by one. However, as shown in FIG. When the paper feed area 20a of the paper roller 20 contacts the separating piece 6 and separates the originals 1 one by one and feeds them, the paper feeding roller 20 raises the separating piece 6 and the supporting plate 7 holding it. It has been pushed up to the side, so that the claws 36 on both sides
Is separated from the inclined guide surface 2b of the document guide 2 and does not interfere with the passing document. However, FIG.
As shown in FIG.
When 0b is stopped at the position facing the separating piece 6, the separating piece 6 is descending downward, so that the claw 36 comes into contact with the inclined guide surface 2b of the document guide 2. Therefore, when the second and subsequent documents are about to pass, the document hits the pawl 36 and is prevented from further passing.
As a result, double feeding of documents is prevented.

22 and 23 to 25 show an embodiment of the invention described in claim 8. In this embodiment, circular rings 38 are provided on both sides of the paper feed roller 20 on the same axis as the paper feed roller 20. Further, the separating piece 6B used here is formed with a separating piece 6c pressed against the paper feed roller 20 and an auxiliary separating piece 6d capable of contacting the circular rings 38 on both sides. Separation pieces 6c and 6 of separation piece 6B
Similarly to the other embodiments, d is pressed against the paper feed roller 20 and the circular ring 38 by the lower end portion of the support plate 7 holding the separation piece 6B. The pressing mechanism for the auxiliary separation piece 6d can be provided independently of the separation piece 6c. The circular ring 38 is made of a material having a low friction surface such as plastic. The circular ring 38 may be rotated integrally with the paper feed roller 20, or may be rotatable independently of the paper feed roller 20.

In this embodiment, as shown in FIG. 23, after the original 1 is set, the paper feed roller 20 rotates and the originals 1 are separated and fed one by one. As described above, while the paper feed area 20a of the paper feed roller 20 moves while contacting the separation piece 6c, the originals 1 are separated and fed one by one. Then, when the fed document 1 is fed to the downstream feed roller 11 and is started to be conveyed by the feed roller 11, as shown in FIG. 25, the non-paper feed region 20b of the paper feed roller 20 faces the separation piece 6c. Paper feed roller 2 at the position
0 stops. Even at this time, the manuscript 1 is the auxiliary separation piece 6
Although the circular ring 38 is pressed against the outer periphery of the circular ring 38 by d, since the surface of the circular ring 38 has low friction, even if the circular ring 38 is configured to rotate integrally with the sheet feeding roller 20, the circular ring 38 is It is hardly rotated by the running original 1, and the paper feed roller 20 stops at the position shown in FIG. In this state, the feed roller 1
When the second and subsequent originals are pulled out following the original pulled out by 1, the auxiliary separation is performed when the second and subsequent originals try to pass between the circular ring 38 and the auxiliary separation piece 6d. The piece 6d gives friction resistance to the original. As a result, double feeding of documents is prevented.

Although the auxiliary separating piece 6d is integrated with the central separating piece 6c in this embodiment, the auxiliary separating piece 6d may be a separate component.

26, 27 and 28 show an embodiment of the invention described in claim 9. In this embodiment, instead of the circular rings 38 arranged on both sides of the paper feed roller 20 in the embodiment of FIG. 22, the circular ring 38 has substantially the same radius (that is, substantially the same radius as the paper feed area of the paper feed roller 20). The arc-shaped convex portion 40 is formed integrally with the document guide 2. Further, a separating piece 6B having the same structure as the separating piece used in the embodiment of FIG. 22 is provided. In other words, the separation piece 6B includes a separation piece 6c that is pressed against the sheet feeding roller 20 and an auxiliary separation piece 6 that can contact the convex portions 40 on both sides.
d is formed. Separation pieces 6c and 6d of separation piece 6B
In the same manner as in the other embodiments, the lower end of the support plate 7 holding the separation piece 6B is pressed against the paper feed roller 20 and the convex portion 40, respectively. The auxiliary separating piece 6d
It is also possible to separately provide the pressing mechanism of 1 separately from the separation piece 6c. Although the convex portion 40 is integrally formed as a part of the document guide 2, the convex portion 40 may be formed as a separate component from the document guide 2 and fixed to the document guide 2 instead. It is preferable that the surface of the convex portion 40 has low friction, and it is preferable that a low-friction film is attached or a low-friction material is coated.

Also in the embodiment having this structure, as shown in FIG. 27, the original 1 is set when the non-paper feeding area 20b of the paper feeding roller 20 is stopped in a state of facing the separating piece, and then the paper is fed. As the paper roller 20 rotates, as shown in FIG. 28, the originals 1 are separated and fed one by one while the paper feeding area 20a of the paper feeding roller 20 moves in contact with the separating piece 6c.
Then, when the fed document 1 is fed to the downstream feed roller 11 and is started to be conveyed by the feed roller 11,
As shown in FIG. 27, the non-paper feeding area 20 of the paper feeding roller 20.
The paper feed roller 20 stops at a position where b is opposed to the separation piece 6c. In this state, when the second and subsequent originals are drawn out following the originals drawn by the feed roller 11, the second and subsequent originals try to pass between the convex portion 40 and the auxiliary separating piece 6d. In doing so, the auxiliary separating piece 6d gives friction resistance to the original. As a result, double feeding of documents is prevented. When the convex portion 40 is used as in this embodiment, FIG.
Compared with the case of using the circular ring 38 of the above embodiment, the structure is simpler, and there is an advantage that the device can be downsized.

Although the auxiliary separating piece 6d is integrated with the central separating piece 6c in this embodiment, the auxiliary separating piece 6d may be a separate component.

The paper feed roller used in the present invention can be modified in addition to the shapes shown in FIGS. 2 to 4, one example of which is shown in FIG. In the embodiment shown in FIG. 29, the paper feed roller 42 having a blade-shaped protrusion 42a on the outer circumference is used. The protrusion 42a is made of an elastically deformable material such as rubber, and when the paper feed roller 42 rotates, the protrusion 42a shown in FIG.
As shown in (a), the tip is pressed against the separation piece 6, and the length is such that it can move while elastically deforming. The tip of the protrusion 42a forms a paper feeding area for feeding the original while separating the original in cooperation with the separating piece 6.
The other part constitutes the non-paper feed area. It should be noted that although the drawing does not show the auxiliary separating means for preventing the double feeding of the originals, the auxiliary separating means as used in the above-described embodiment is provided.

In the embodiment shown in FIG. 29, FIG.
As shown in (b), the paper feed roller 42 is stopped with the protrusion 42a 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 leading end of the document 1 can be inserted deeply below the separation piece 6 and set. Next, when the paper feed roller 42 rotates to feed the paper, the protrusion 42a contacts the lower surface of the original 1 and lifts it up, and as shown in FIG. Move while pressing. As a result, a conveyance force is applied to the original document, the original document is pulled out, and the separating pieces 6 prevent the original document from being double-fed. When the original fed by the paper feed roller 42 is subsequently conveyed by the feed roller 11, the paper feed roller 42 is stopped at the position shown in FIG. 29B, so that the original being fed is not conveyed. Resistance is prevented and chattering noise generated by the separation piece 6 is prevented. At this time, although the effect of separating the originals by the separating pieces 6 is lowered, the auxiliary separating means (not shown) prevents the double feeding of the originals.

[0066]

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. Moreover, when the non-feeding area of the paper feed roller is stopped at a position facing the separating piece and the pressing force of the separating piece against the original document is reduced, the separating force may be reduced and the document may be double-fed. Since the auxiliary separating means is provided, it is possible to prevent the double feeding of the originals and no trouble occurs.

Further, according to the present invention, when the paper feed roller starts rotating to start feeding the original, the front end of the paper feed area of the paper feed roller is at the same time over the entire width of the paper feed roller and at a short distance from the front end of the original. Since the original sheet is brought into contact with the portion on which the original is placed and the original sheet is conveyed, the conveying force is extremely large. Therefore, the original sheet can be reliably fed, and even if the number of original sheets set is increased, the original sheet can be fed well. Therefore, it is possible to omit the introduction roller, and further, even if the document is set obliquely, it is possible to feed the document without expanding the bending of the document.

[Brief description of drawings]

FIG. 1 is a schematic perspective view of a main part 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 of the sheet feeding device in a state where a sheet is fed while a sheet feeding roller separates an original, and is cut in the vicinity of the sheet feeding roller; Schematic cross-sectional view showing the device with the paper feed roller stopped

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

5 is a schematic cross-sectional view showing the sheet feeding device in the embodiment shown in FIG. 1 by cutting the sheet feeding device at a position farther from the sheet feeding roller than the cutting position shown in FIG.

FIG. 6 is a schematic perspective view of a main part of the sheet feeding device of the embodiment shown in FIG.

FIG. 7 is a schematic perspective view showing a main part of a paper feeding device according to another embodiment of the present invention.

FIG. 8 is a schematic perspective view showing a main part of a paper feeding device according to still another embodiment of the present invention.

9 is a schematic sectional view of the embodiment of FIG.

FIG. 10 is a schematic perspective view showing a main part of a paper feeding device according to still another embodiment of the present invention.

11 is a schematic sectional view of the embodiment of FIG.

FIG. 12 is a schematic perspective view showing a main part of a paper feeding device according to still another embodiment of the present invention.

13 is a schematic sectional view of the embodiment of FIG.

FIG. 14 is a schematic perspective view showing a main part of a paper feeding device according to still another embodiment of the present invention.

FIG. 15 is a schematic sectional view showing the embodiment of FIG. 14 with a document set.

FIG. 16 is a schematic cross-sectional view showing the embodiment of FIG. 14 in a state where the paper feed roller feeds a document while separating it;

FIG. 17 is a schematic cross-sectional view showing the embodiment of FIG. 14 in a state where the paper feed roller is stopped.

FIG. 18 is a schematic perspective view showing a main part of a paper feeding device according to still another embodiment of the present invention.

FIG. 19 is a schematic sectional view showing the embodiment of FIG. 18 with a document set.

FIG. 20 is a schematic cross-sectional view showing the embodiment of FIG. 18 in a state where a paper feed roller feeds a document while separating it;

FIG. 21 is a schematic cross-sectional view showing the embodiment of FIG. 18 with the paper feed roller stopped.

FIG. 22 is a schematic perspective view showing a main part of a paper feeding device according to still another embodiment of the present invention.

FIG. 23 is a schematic sectional view showing the embodiment of FIG. 22 with a document set.

FIG. 24 is a schematic cross-sectional view showing the embodiment of FIG. 22 in a state where a paper feed roller feeds a document while separating it;

FIG. 25 is a schematic cross-sectional view showing the embodiment of FIG. 22 with the paper feed roller stopped.

FIG. 26 is a schematic perspective view showing a main part of a paper feeding device according to still another embodiment of the present invention.

FIG. 27 is a schematic cross-sectional view showing the embodiment of FIG. 26 in a state in which a document is set by cutting at a position of a convex portion provided on the embodiment.

FIG. 28 is a schematic cross-sectional view showing the embodiment of FIG. 26 in a state where the paper is cut at the position of the convex portion and the paper is fed while the paper feed roller separates the original.

FIG. 29 (a) is a schematic cross-sectional view showing a sheet feeding device according to still another embodiment of the present invention in a state in which a sheet feeding roller separates a document while feeding it. FIG. Schematic sectional view showing the paper feed roller stopped

FIG. 30 is a schematic perspective view of a main part of a facsimile device using a conventional paper feeding device.

FIG. 31 is a schematic sectional view of a conventional paper feeding device.

[Explanation of symbols]

 1 Document 2 Document Guide 2a Supporting Surface 2b Inclined Guide Surface 3 Introducing Roller 5, 20, 23, 24, 26, 28 Paper Feeding Roller 6, 6A, 6B Separation Piece 6b, 6d Auxiliary Separation Piece 7 Support Plate 8 Pressing Member 9 Spring 10 upper surface guide 11 feed roller 20a, 23a, 24a, 26a, 28a paper feeding area 20b, 23b, 24b, 26b, 28b non-paper feeding area 22 leaf spring 22A film 30 sponge 32 leaf spring 32a claw 34 rubber plate 36 claw 38 circular Ring 40 convex

Claims (9)

[Claims] 1. A document guide having a support surface forming a part of the document table and an inclined guide surface tilted downward with respect to the support surface, and a feed unit arranged to draw in a document set on the document table. A paper roller, a separating piece provided corresponding to the paper feeding roller to prevent double feeding of originals, a pressing means for pressing the separating piece against the paper feeding roller, and an auxiliary separating means for preventing double feeding of originals 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. The pressing force of the separating piece on the non-paper feeding area of the paper roller is set to be lower than or equal to 0 than the pressing force on the paper feeding area. On the supporting surface of the document guide, above the inclined guide surface. A sheet feeding device having a leaf spring attached so as to extend. 2. A document guide having a support surface forming a part of the document table and an inclined guide surface tilted downward with respect to the support surface, and a feeding unit arranged to draw in a document set on the document table. A paper roller, a separating piece provided corresponding to the paper feeding roller to prevent double feeding of originals, a pressing means for pressing the separating piece against the paper feeding roller, and an auxiliary separating means for preventing double feeding of originals 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. The pressing force of the separating piece on the non-paper feeding area of the paper roller is set to be lower than or equal to 0 than the pressing force on the paper feeding area. On the supporting surface of the document guide, above the inclined guide surface. A sheet feeder having a film attached so as to extend. 3. A document guide having a support surface forming a part of the document table and an inclined guide surface tilted downward with respect to the support surface, and a feeding unit arranged so as to pull in a document set on the document table. A paper roller, a separating piece provided corresponding to the paper feeding roller to prevent double feeding of originals, a pressing means for pressing the separating piece against the paper feeding roller, and an auxiliary separating means for preventing double feeding of originals 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. The pressing force of the separating piece on the non-paper feeding area of the paper roller is set to be lower than or equal to 0 than the pressing force on the paper feeding area. On the upper guide and A sheet feeding device having sponges attached to both sides of the sheet feeding roller. 4. A document guide having a support surface forming a part of the document table and an inclined guide surface inclined downwardly with respect to the support surface, and a feeding unit arranged so as to pull in a document set on the document table. A paper roller, a separating piece provided corresponding to the paper feeding roller to prevent double feeding of originals, a pressing means for pressing the separating piece against the paper feeding roller, and an auxiliary separating means for preventing double feeding of originals 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. The pressing force of the separating piece on the non-paper feeding area of the paper roller is set to be lower than or equal to 0 than the pressing force on the paper feeding area. On the supporting surface of the document guide, above the inclined guide surface. A film attached so as to extend, an upper surface guide provided so as to face the document guide, and a leaf spring having pawls attached to both ends of the paper feed roller on the upper surface guide. Paper feeding device. 5. A document guide having a support surface forming a part of the document table and an inclined guide surface inclined downwardly with respect to the support surface, and a feeding unit arranged to pull in a document set on the document table. A paper roller, a separating piece provided corresponding to the paper feeding roller to prevent double feeding of originals, a pressing means for pressing the separating piece against the paper feeding roller, and an auxiliary separating means for preventing double feeding of originals 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. The pressing force of the separating piece on the non-paper feeding area of the paper roller is set to be lower than or equal to 0 than the pressing force on the paper feeding area. On the supporting surface of the document guide, above the inclined guide surface. A sheet feeding device comprising a film attached so as to extend, an upper surface guide provided so as to face the document guide, and rubber plates attached to both sides of the sheet feeding roller on the upper surface guide. 6. A document guide having a support surface forming a part of the document table and an inclined guide surface inclined downwardly with respect to the support surface, and a feeding unit arranged to draw in a document set on the document table. A paper roller, a separating piece provided corresponding to the paper feeding roller to prevent double feeding of originals, a pressing means for pressing the separating piece against the paper feeding roller, and an auxiliary separating means for preventing double feeding of originals 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. The pressing force of the separating piece on the non-paper feeding area of the paper roller is set to be lower than or equal to 0 than the pressing force on the paper feeding area. Is installed so that it can contact the inclined guide surface of the document guide. A sheet feeding device having an auxiliary separating piece, which is configured to move up and down in conjunction with the separating piece pressed against the sheet feeding roller. 7. A document guide having a support surface forming a part of the document table and an inclined guide surface inclined downwardly with respect to the support surface, and a feed unit arranged to draw in a document set on the document table. A paper roller, a separating piece provided corresponding to the paper feeding roller to prevent double feeding of originals, a pressing means for pressing the separating piece against the paper feeding roller, and an auxiliary separating means for preventing double feeding of originals 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. The pressing force of the separating piece on the non-paper feeding area of the paper roller is set to be lower than or equal to 0 than the pressing force on the paper feeding area. Is installed so that it can contact the inclined guide surface of the document guide. A sheet feeding device having a broken claw, the claw moving up and down in conjunction with a separating piece pressed against the sheet feeding roller. 8. A document guide having a support surface forming a part of the document table and an inclined guide surface tilted downward with respect to the support surface, and a feeding unit arranged so as to pull in a document set on the document table. A paper roller, a separating piece provided corresponding to the paper feeding roller to prevent double feeding of originals, a pressing means for pressing the separating piece against the paper feeding roller, and an auxiliary separating means for preventing double feeding of originals 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. The pressing force of the separating piece on the non-paper feeding area of the paper roller is set to be lower than or equal to 0 than the pressing force on the paper feeding area. , Or provided on one side on the same axis as the paper feed roller A sheet feeding device comprising a circular ring and an auxiliary separating piece provided so as to be pressed against the circular ring. 9. A document guide having a support surface forming a part of the document table and an inclined guide surface tilted downward with respect to the support surface, and a feeding unit arranged to pull in a document set on the document table. A paper roller, a separating piece provided corresponding to the paper feeding roller to prevent double feeding of originals, a pressing means for pressing the separating piece against the paper feeding roller, and an auxiliary separating means for preventing double feeding of originals 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. The pressing force of the separation piece of the paper roller with respect to the non-feeding area is made lower than the pressing force of the paper feeding area or is set to 0. Further, the auxiliary separating means is provided in the vicinity of the feeding roller. Arc-shaped convex part provided on the and pressed on the convex part And an auxiliary separating piece provided so as to be provided.