JP2008308314A - Sheet feeding apparatus, image forming apparatus, and image reading apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress vibration generated when a feed roller is brought into contact with a separation pad to prevent generation of abnormal noise (chattering) caused by the vibration, without reduction in sheet carrying speed or without deterioration in separating/feeding performance of a sheet. <P>SOLUTION: The sheet feeding device comprises: the feed roller 102 having a feed roller surface 102r formed at a part in a rotational direction thereof; the separation pad 104 separating the sheet at a pinching part between the feed roller surface 102r and the separation pad 104; a separation pad holding member 103 pressing the separation pad 104 against the feed roller 102; and a roller 109 coaxial with the feed roller 102 and abutted with the separation pad 104 while its pinching state between the feed roller surface 102r and the separation pad is released. A boundary 103b between the separation pad holding member 103 and the separation pad 104 in a sheet carrying direction is set so that the feed roller surface 102r is abutted with the separation pad holding member 103 and the separation pad 104 through the sheet S in this order while the feed roller 102 is rotated. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a sheet feeding apparatus that separates and feeds sheets such as originals and recording paper one by one, an image forming apparatus such as a copying machine, a facsimile, and a printer having the sheet feeding apparatus, and the sheet feeding apparatus. The present invention relates to an image reading apparatus such as a scanner.

  In an image forming apparatus such as a copying machine or a printer, a sheet feeding device that separates and feeds sheets such as originals and recording paper one by one is required to have stable feeding performance and reduce operating noise. Yes. As a conventional sheet feeding apparatus, a system is known in which sheets are separated one by one by a half-moon shaped feeding roller and a separation pad pressed against the feeding roller. In this separation type sheet feeding apparatus, vibration may occur between the feeding roller and the separation pad depending on the type of sheet to be fed, and abnormal noise (chattering noise) may occur due to this vibration.

  Therefore, as in Patent Document 1, a technique for preventing the generation of abnormal noise by providing a vibration damping member on the separation pad and preventing the vibration of the separation pad has been proposed. According to this configuration, an effect of suppressing the vibration of the separation pad that is generated when the sheet fed at a constant speed rubs against the separation pad can be obtained.

JP-A-8-91608

  However, even with the above-described conventional technology, vibration due to friction between the sheet and the separation pad that occurs when the feeding roller that rotates during sheet feeding contacts the separation pad through the sheet cannot be prevented. This vibration generates abnormal noise (billing noise).

  In order to suppress the occurrence of the abnormal noise, it is conceivable to reduce the pressing force of the separation pad against the feeding roller or to reduce the friction coefficient of the separation pad. Therefore, sufficient separation and feeding performance cannot be obtained.

  Further, in the configuration that reduces the collision when the feeding roller contacts the separation pad, it is conceivable to reduce the rotation speed of the feeding roller to a speed at which the abnormal noise does not occur, but this reduces the sheet conveyance speed. Resulting in.

  Accordingly, an object of the present invention is to suppress vibrations that occur when the feeding roller comes into contact with the separation pad without lowering the sheet conveyance speed and separation / feeding performance. It is to prevent the occurrence.

  In order to achieve the above object, a typical configuration of the present invention includes a feeding roller having a roller surface that feeds a sheet in a part of the rotation direction, and a clamping surface that faces the feeding roller and the roller surface. A separation pad that separates the sheet at a portion, a swingable separation pad holding member that holds the separation pad and presses the separation pad against the feeding roller, and is rotatable coaxially with the feeding roller A roller member that is in contact with a separation pad that is in a state of being held between the roller surface and the roller surface, and when the feeding roller rotates, the roller surface is separated from the separation pad holding member via the sheet. A boundary between the separation pad holding member and the separation pad in the sheet conveying direction is set so as to contact each other in the order of the pads.

  According to the present invention, the vibration generated when the feeding roller comes into contact with the separation pad via the sheet is suppressed without deteriorating the sheet conveyance speed and the separation feeding performance, and an abnormal noise (chattering noise) due to this vibration is suppressed. Can be prevented.

  Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. However, the dimensions, materials, shapes, and relative arrangements of the components described in the following embodiments should be changed as appropriate according to the configuration of the apparatus to which the present invention is applied and various conditions. Therefore, unless specifically stated otherwise, the scope of the present invention is not intended to be limited thereto.

[First Embodiment]
FIG. 1 is a schematic configuration diagram illustrating an example of an image forming apparatus having a sheet feeding device, and FIG. 2 is a perspective view of a main part of the sheet feeding device.

  As shown in FIGS. 1 and 2, the intermediate plate 101 is provided in the feeding cassette 114, and pushes up the sheets S stacked thereon by the force of the urging spring 113. The feed roller 102 is fixed to a support shaft 108 and is rotatably supported. The uppermost sheet leading end side of the sheet S pushed up by the intermediate plate 101 contacts the feeding roller 102. The feeding roller 102 has a roller surface 102r for feeding a sheet. The roller surface 102r is formed in a circular arc shape in cross section, and is provided in a part of the rotation direction of the feeding roller. Here, the feeding roller 102 has a roller surface 102r having a semicircular cross section. Further, the front portion 102ra (shown in FIG. 8) of the roller surface 102r in the rotational direction is formed in a smooth arc shape so that the diameter from the axis of the support shaft 108 gradually decreases.

  A circular abutting roller (roller member) 109 is rotatably provided on both sides of the feeding roller 102 in the sheet width direction orthogonal to the sheet conveying direction on the support shaft 108 to which the feeding roller 102 is fixed. Yes. That is, the abutting roller 109 is provided so as to be rotatable on the same axis as the feeding roller 102.

  The separation pad 104 faces the feeding roller 102 and separates the sheet at a holding portion with the roller surface 102r. The separation pad holding member 103 holds the separation pad 104 and presses the separation pad 104 against the feeding roller 102. The separation pad holding member 103 is provided below the feeding roller 102 and can swing within a predetermined range around the hinge portion h. The separation pad 104 is provided above the separation pad holding member 103 and contacts the lower side of the feeding roller 102. The spring 105 urges the separation pad holding member 103 toward the feeding roller 102. The conveyance guide 106 serves as a conveyance path for the sheet S conveyed by the feeding roller 102. The conveyance roller 107 conveys the sheet S to the next process.

  The conveyed sheet S is conveyed by the transfer belt 115, and after toner images are transferred from the photosensitive drums 110 </ b> K, 110 </ b> C, 110 </ b> M, and 110 </ b> Y, the sheet S is fixed by the thermal fixing device 111 and discharged to the discharge tray 112.

  The radius Ra of the roller surface 102r of the feeding roller 102 is larger than the radius Rb of the abutting roller 109 (Ra> Rb). Therefore, when the abutment roller 109 is attached to the support shaft 108, the outer peripheral surface of the abutment roller 109 is positioned on the inner side of the roller surface 102r. Therefore, the abutting roller 109 does not contact the separation pad 104 when the roller surface 102r of the feeding roller 102 and the separation pad 104 are nipped, and the nipping state between the roller surface 102r of the feeding roller 102 is released. The separated pad 104 comes into contact.

  FIG. 3 is a schematic cross-sectional view showing a standby state before sheet separation and feeding. The sheet S placed on the intermediate plate 101 is lifted upward by the biasing spring 113 (see FIG. 1). As a result, the uppermost sheet leading end portion of the sheet S stops in a state where it abuts against the abutting roller 109, and the sheet can be fed. Further, the separation pad 104 is in contact with the abutting roller 109 by urging from the spring 105. For this reason, the position of the separation pad 104 in the standby state is determined by the abutment roller 109.

  FIG. 4 is a schematic cross-sectional view showing a state during sheet separation and feeding. When the feeding operation is started, as shown in FIG. 4, the feeding roller 102 rotates, so that the roller surface 102r of the feeding roller 102 comes into contact with the uppermost sheet S, and the uppermost sheet S is moved. Be fed. The fed sheet S is conveyed to the conveying roller 107 through a nip portion that is a nipping portion between the feeding roller surface 102r and the separation pad 104.

  Here, the sheet S between the feeding roller surface 102 r and the separation pad 104 is pressed against the separation pad 104 by the feeding roller 102. The relationship of the frictional force μ1 between the separation pad 104 and the sheet, the frictional force μ2 between the sheets, and the frictional force μ3 between the sheet and the feeding roller 102 is configured to satisfy μ2 <μ1 <μ3. Accordingly, even when a plurality of sheets are simultaneously fed by the sheet S of the feeding roller 102, the sheets can be separated and fed one by one.

  The feed roller 102 rotates once by a clutch mechanism (not shown). At this time, the sheet S conveys the leading edge of the sheet S to the conveying roller 107 as shown in FIG. Thereafter, as shown in FIG. 6, the feeding roller 102 stops so that the roller surface 102 r of the feeding roller 102 is missing, that is, the abutting roller 109 faces the separation pad 104.

  At this time, the conveyance roller 107 continues to convey the sheet S. For this reason, the sheet S passing between the abutment roller 109 and the separation pad 104 is conveyed by the conveyance roller 107 while being held between the abutment roller 109 and the separation pad 104. At this time, the abutting roller 109 is not fixed to the support shaft 108, and therefore follows the sheet S being conveyed. In this way, the abutting roller 109 rotates and the sheet S is conveyed while being in contact with the separation pad 104, thereby preventing the double feeding of the sheet S with a small back tension against the conveying force.

  As shown in FIG. 4, the feeding roller 102 contacts the separation pad 104 via the sheet S during the sheet separation operation. At that time, the separation pad holding member 103 is pushed by the feed roller 102 and rotates around the hinge portion h. Therefore, the feeding roller 102 is suddenly received by the reaction force of the spring 105 of the separation pad holding member 103, and the sheet S and the separation pad 104 are strongly rubbed at the contact portion with the feeding roller surface 102r. As a result, stick slip (friction vibration phenomenon) occurs between the sheet S and the separation pad 104 depending on the type of the sheet S and the environmental atmosphere (temperature and humidity), thereby generating noise (hereinafter referred to as pad squeal) due to the stick slip. there's a possibility that. The stick-slip is a phenomenon in which when an object slides, the object repeatedly slides or gets caught on a certain surface due to friction between the objects, and frictional vibration is generated.

  The occurrence of pad noise can be suppressed by lowering the spring pressure of the spring 105 that presses the separation pad holding member 103. However, depending on the type of the sheet S, the sheet S cannot be sufficiently separated and double feeding occurs, which is difficult to implement. Further, it may be possible to prevent pad noise by changing the friction coefficient between the feeding roller 102 and the separation pad 104, but it is difficult to find a combination of materials corresponding to the type of the sheet S, changes in the environment, and the like. It is.

  Therefore, when the feeding roller 102 is rotated, the separation pad holding member 103 in the sheet conveying direction and the separation pad holding member 103 and the separation pad 104 are in contact with each other in this order through the sheet S. A boundary with the separation pad 104 is set. This will be described in detail with reference to FIGS.

  The boundary between the separation pad holding member 103 and the separation pad 104 is a boundary line 103b shown in FIG. When the feeding roller 102 rotates once, the feeding roller surface 102r first comes into contact with the vicinity of the boundary line 103b of the separation pad holding member 103 (point A1) as shown in FIG. Next, as shown in FIG. 9, the peripheral surface of the feeding roller surface 102r contacts the separation pad 104 via the sheet S (point A2). In this way, the boundary line 103b between the separation pad holding member 103 and the separation pad 104 is disposed. When the point A2 is reached, the separation pad holding member 103 and the feeding roller surface 102r are not in contact with each other.

  That is, before the roller surface 102r of the feeding roller 102 contacts the separation pad 104 via the sheet S (A2), the roller surface 102r contacts the separation pad holding member 103 (A1). Since the separation pad holding member 103 uses a resin member (here, PPE + PS), the friction coefficient of the surface is smaller than the friction coefficient of the separation pad 104. Therefore, when the feeding roller 102 comes into contact with the sheet S, the separation pad holding member 103 and the sheet S slide, and no stick slip occurs between the feeding roller 102 and the sheet S, and pad noise also occurs. do not do. At this time, the angle of the separation pad holding member 103 is already maintained almost in the posture of the sheet separation operation by the contact with the previous feeding roller 102. Therefore, the next time when the separation pad 104 and the feeding roller 102 come into contact with each other via the sheet S, they can be brought into contact with each other without a large change in angle. Therefore, the pad squealing can be prevented without the separation pad 104 and the sheet S being rubbed strongly at the time of contact with the feeding roller 102.

  If the boundary line 103b between the separation pad holding member 103 and the separation pad 104 is disposed too far downstream in the sheet conveyance direction from the set position, the following occurs. That is, even after the front portion 102ra contacts the separation pad holding member 103, the feeding roller surface 102r remains in contact with the separation pad holding member 103 and cannot fully contact the separation pad 104 via the sheet. Sheet double feed occurs. Further, if the boundary line 103b between the separation pad holding member 103 and the separation pad 104 is disposed on the upstream side in the sheet conveying direction from the set position, the feeding roller surface 102r does not contact the separation pad holding member 103 via the sheet. As in the conventional case, pad noise is generated. Further, if the sheet S is disposed on the upstream side, the leading edge of the fed sheet S enters the separation pad 104 at an obtuse angle, so that a catching conveyance failure is likely to occur.

  As described above, in the present embodiment, the boundary line 103b between the separation pad holding member 103 and the separation pad 104 is arranged in the order of the separation pad holding member 103 and the separation pad 104 through the sheet S on the feeding roller surface 102r. It is set so that it touches. This suppresses vibrations that occur when the feeding roller 102 comes into contact with the separation pad 104 via the sheet without lowering the sheet conveyance speed and separation / feeding performance. Occurrence can be prevented.

[Second Embodiment]
A sheet feeding apparatus according to the second embodiment will be described with reference to FIG. Since the mechanical structure in the present embodiment is almost the same as that in the first embodiment, the reference numerals in FIGS. 1 to 9 are used, and description of these structural elements is omitted. Also, the operation of the second embodiment is the same as that of the first embodiment, and the description thereof is omitted.

  In the present embodiment, of the boundary line 103b between the separation pad holding member 103 and the separation pad 104, the boundary line of the second region other than the boundary line 103b1 of the first region where the feeding roller surface 102r abuts. 103b2 is provided on the upstream side in the sheet conveying direction. Here, the distance t between the boundary line 103b1 and the boundary line 103b2 is 0.8 mm. However, if the boundary line 103b2 is further set on the upstream side in the sheet conveyance direction (distance t> 2 mm in this case), the leading edge of the fed sheet S is caught on the separation pad 104, and conveyance failure is likely to occur.

  Further, the second region of the separation pad holding member 103 is provided on both sides of the first region (width 103w) in the sheet width direction. Furthermore, the width of the boundary line 103b1 of the first region (width 103w) is set to be narrower than the width between the butting rollers 109. Here, the width 103w as the first region is the same as the length of the feeding roller surface 102r in the sheet width direction.

  When the feed roller 102 rotates once, the feed roller surface 102r first comes into contact with the vicinity of the boundary line 103b1 of the separation pad holding member 103 (point A1) as shown in FIG. Next, as shown in FIG. 9, the peripheral surface of the feeding roller surface 102r contacts the separation pad 104 via the sheet S (point A2). Thus, the boundary line 103b1 between the separation pad holding member 103 and the separation pad 104 is arranged. When the point A2 is reached, the separation pad holding member 103 and the feeding roller surface 102r are not in contact with each other.

  Also, as shown in FIG. 10, among the boundary lines 103b between the separation pad holding member 103 and the separation pad 104, only the central boundary line 103b1 protrudes in the sheet conveying direction as compared with the boundary line 103b2 on both sides in the sheet width direction. ing. Thereby, in the range of the boundary line 103b2 at both ends of the separation pad 104, the leading edge of the sheet S comes into contact with the separation pad 104 before the boundary line 103b1. For this reason, when the sheets are fed in a double feed, the function of preventing the double feed is prevented by the sheet separation effect that separates the sheets S. Note that since the feeding roller surface 102r does not face the boundary line 103b2, even if the leading edge of the sheet S contacts the separation pad 104 before the vicinity of the boundary line 103b1 of the separation pad holding member 103, vibration occurs. No abnormal noise is generated.

[Third Embodiment]
A sheet feeding apparatus according to a third embodiment will be described with reference to FIG. In addition, since the mechanical structure in this embodiment is substantially the same as that of the first and second embodiments, the reference numerals in FIGS. 1 to 9 are used and description of these structural elements is omitted. The operation of the third embodiment is also the same as that of the first and second embodiments, and the description thereof is omitted.

  In this embodiment, the separation pad holding member 103 is a region (width 103w) where the feeding roller surface 102r abuts, and is made of a material harder than the separation pad holding member 103 on the upstream side in the sheet conveyance direction of the separation pad 104. Thus, the rubbing member 103s having a good surface property is held. Here, a SUS plate was used as the rubbing member 103s. Then, when the feeding roller 102 rotates, the rubbing member 103s and the separation pad 104 in the sheet conveying direction so that the feeding roller surface 102r contacts the rubbing member 103s and the separation pad 104 in this order via the sheet. And set the boundary.

  Further, the separation pad holding member 103 forms the boundary line 103b2 with the other separation pad holding member 103 from the boundary line 103b1 with the rubbing member 103s out of the boundary line 103b with the separation pad 104 in the sheet conveyance direction. It is provided upstream in the transport direction.

  Further, in the sheet width direction, the boundary line 103b2 of the separation pad holding member 103 with respect to the separation pad 104 is provided on both sides of the boundary line 103b1 of the rubbing member 103s. Furthermore, the width (width 103w) of the boundary line 103b1 of the rubbing member 103s is set to be narrower than the width between the abutting rollers 109.

  When the separation pad holding member 103 is made of a soft material (resin such as ABS), when the feeding roller 102 repeatedly contacts the separation pad holding member 103 via the sheet S, the separation pad holding member 103 is separated by the leading edge of the sheet S. The pad holding member 103 may be scraped off. Further, when the separation pad holding member 103 is made of a material having a poor surface property (a resin member having a high glass content), the leading edge of the sheet S is caught by the separation pad holding member 103 due to the poor surface property. Defects may occur. Therefore, by using the rubbing member 103s (SUS plate) as in the present embodiment, stable sheet conveyance is possible.

  Further, during one rotation of the feeding roller 102, the feeding roller surface 102r first comes into contact with the vicinity of the boundary line 103b1 of the rubbing member 103s via the sheet. Next, the peripheral surface of the feed roller surface 102r contacts the separation pad 104 via the sheet. For this reason, even while the sheet is rubbed between the feeding roller 102 and the rubbing member 103s, slip occurs between the sheet and the rubbing member 103s, and stick slip does not occur between the feeding roller 102 and the sheet. Therefore, pad noise can be prevented more than in the embodiment described above.

  In addition, it is possible to similarly suppress pad noise by using another material having a small surface friction coefficient for the rubbing member 103s.

[Fourth Embodiment]
A sheet feeding apparatus according to the fourth embodiment will be described with reference to FIG. Since the mechanical structure in this embodiment is almost the same as that in the first, second, and third embodiments, the reference numerals in FIGS. 1 to 9 are used, and description of these structural elements is omitted. . The operation of the fourth embodiment is also the same as that of the first, second, and third embodiments, so that the description thereof is omitted.

  In the present embodiment, the separation pad holding member 103 is a region (width 103w) with which the feeding roller surface 102r abuts, and has a smaller friction coefficient than the separation pad 104 on the upstream side in the sheet conveyance direction of the separation pad 104. The member 103e is held. Here, an elastomer member such as urethane or rubber is used as the rubbing member 103e. Here, the friction coefficient of the separation pad 104 is 0.9 to 0.8, and the friction coefficient of the rubbing member (elastomer member) 103e is 0.6 to 0.5. Then, when the feeding roller 102 rotates, the rubbing member 103e and the separation pad 104 in the sheet conveying direction so that the feeding roller surface 102r contacts the rubbing member 103e and the separation pad 104 in this order via the sheet. And set the boundary.

  Further, the separation pad holding member 103 forms the boundary line 103b2 with the other separation pad holding member 103 from the boundary line 103b1 with the rubbing member 103e out of the boundary line 103b with the separation pad 104 in the sheet conveyance direction. It is provided upstream in the transport direction.

  Further, in the sheet width direction, the boundary line 103b2 of the separation pad holding member 103 with respect to the separation pad 104 is provided on both sides of the boundary line 103b1 of the rubbing member 103e. Furthermore, the width (width 103w) of the boundary line 103b1 of the rubbing member 103e is set to be narrower than the width between the abutting rollers 109.

  Further, during one rotation operation of the feed roller 102, the feed roller surface 102r first comes into contact with the vicinity of the boundary line 103b1 of the rubbing member 103e through the sheet. Next, the peripheral surface of the feed roller surface 102r contacts the separation pad 104 through the sheet. For this reason, even while the sheet is rubbed by the feeding roller 102 and the rubbing member 103e, slip occurs between the sheet and the rubbing member 103e, and stick slip does not occur between the feeding roller 102 and the sheet. Therefore, compared to the first and second embodiments described above, pad noise can be prevented more.

  Further, since the rubbing member 103e is smaller than the friction coefficient of the feeding roller 102 and the separation pad 104, not only the pad squeal is prevented but also a plurality of double-fed sheets are formed between the feeding roller 102 and the rubbing member 103e. The sheets are separated while being rubbed together. Alternatively, separation at the separation pad 104 can be assisted, and feeding failure such as double feeding can be prevented.

[Other Embodiments]
In the above-described embodiment, the printer is exemplified as the image forming apparatus, but the present invention is not limited to this. For example, the image forming apparatus may be another image forming apparatus such as a copying machine or a facsimile machine, another image forming apparatus such as a multi-function machine combining these functions, or an image reading apparatus such as a scanner. The same effect can be obtained by applying the present invention to a sheet feeding apparatus used in these image forming apparatuses or image reading apparatuses.

  In the above-described embodiment, the sheet feeding apparatus integrally included in the image forming apparatus is exemplified, but the present invention is not limited to this. For example, a sheet feeding device that is detachable from the image forming apparatus may be used, and the same effect can be obtained by applying the present invention to the sheet feeding device.

  In the above-described embodiment, the sheet feeding apparatus that feeds the sheets one by one toward the recording unit that records an image on a sheet such as recording paper as a recording target is exemplified. It is not limited. For example, the same effect can be obtained even when the present invention is applied to a sheet feeding apparatus that feeds the sheets one by one toward a reading unit that reads an image of a sheet such as a document to be read.

Sectional drawing which shows schematic structure of image forming apparatus which has sheet feeding apparatus Perspective view of essential parts of sheet feeding apparatus Sectional view showing the standby state before the sheet separating and feeding operation of the sheet feeding device Sectional drawing which shows the state at the time of sheet | seat separation feeding of a sheet feeding apparatus Sectional drawing which shows the state at the time of sheet | seat separation conveyance of a sheet feeding apparatus Sectional drawing which shows the state of the sheet feeding apparatus at the time of sheet conveyance 1 is a configuration diagram of a separation pad of a sheet feeding apparatus according to a first embodiment. Enlarged sectional view of the sheet feeding device during sheet feeding operation Enlarged sectional view of the sheet feeding device during sheet feeding operation Configuration diagram of separation pad of sheet feeding apparatus according to second embodiment Configuration diagram of separation pad of sheet feeding apparatus according to third embodiment Configuration diagram of a separation pad of a sheet feeding apparatus according to a fourth embodiment

Explanation of symbols

Ra ... radius of feed roller Rb ... radius S of abutting roller ... sheet h ... hinge 102 ... feed roller 102r ... feed roller surface 103 ... separation pad holding members 103b, 103b1, 103b2 ... boundary lines 103e, 103s ... Rub member 103w ... width 104 ... separation pad 108 ... support shaft 109 ... abutment roller

Claims (10)

A feeding roller having a roller surface for feeding a sheet in a part of the rotation direction;
A separation pad that opposes the feeding roller and separates the sheet at a clamping portion with the roller surface;
A swingable separation pad holding member that holds the separation pad and presses the separation pad against the feeding roller;
A roller member that is rotatably provided on the same axis as the feeding roller and abuts against a separation pad that is in a state of being clamped with the roller surface;
A boundary between the separation pad holding member and the separation pad in the sheet conveying direction is set so that the roller surface contacts the separation pad holding member and the separation pad in this order through the sheet when the feeding roller rotates. A sheet feeding device characterized by being set.   The sheet feeding apparatus according to claim 1, wherein a friction coefficient of a surface of the separation pad holding member is smaller than a friction coefficient of the separation pad.   The separation pad holding member conveys the boundary of the second region other than the boundary of the first region where the roller surface of the feeding roller is in contact with the separation pad in the sheet conveyance direction. The sheet feeding apparatus according to claim 1, wherein the sheet feeding apparatus is provided on an upstream side in the direction.   In the sheet width direction orthogonal to the sheet conveying direction, the roller members are provided on both sides of the roller surface of the feeding roller, the second area of the separation pad holding member is provided on both sides of the first area, and the first area The sheet feeding apparatus according to claim 3, wherein a width of a boundary of the region is narrower than a width between the roller members. A feeding roller having a roller surface for feeding a sheet in a part of the rotation direction;
A separation pad that opposes the feeding roller and separates the sheet at a clamping portion with the roller surface;
A swingable separation pad holding member that holds the separation pad and presses the separation pad against the feeding roller;
A roller member that is rotatably provided on the same axis as the feeding roller and abuts against a separation pad that is in a state of being clamped with the roller surface;
The separation pad holding member is a region where the roller surface abuts, and holds a rubbing member that is harder than the separation pad holding member and has a good surface property on the upstream side in the sheet conveying direction of the separation pad. ,
The boundary between the rubbing member and the separation pad in the sheet conveying direction is set so that the roller surface contacts the rubbing member and the separation pad in this order via the sheet when the feeding roller rotates. A sheet feeding device characterized by that. A feeding roller having a roller surface for feeding a sheet in a part of the rotation direction;
A separation pad that opposes the feeding roller and separates the sheet at a clamping portion with the roller surface;
A swingable separation pad holding member that holds the separation pad and presses the separation pad against the feeding roller;
A roller member that is rotatably provided on the same axis as the feeding roller and abuts against a separation pad that is in a state of being clamped with the roller surface;
The separation pad holding member is a region where the roller surface abuts, and holds a rubbing member having a smaller friction coefficient than the separation pad on the upstream side in the sheet conveying direction of the separation pad,
A boundary between the rubbing member and the separation pad in the sheet conveying direction is set so that the roller surface contacts the rubbing member and the separation pad in this order via the sheet when the feeding roller rotates. A sheet feeding device characterized by that.   The separation pad holding member has a boundary with the separation pad holding member other than the boundary with the rubbing member with which the roller surface of the feeding roller contacts in the boundary with the separation pad in the sheet conveyance direction. The sheet feeding apparatus according to claim 5, wherein the sheet feeding apparatus is provided on the upstream side in the conveying direction.   In the sheet width direction perpendicular to the sheet conveying direction, the roller members are provided on both sides of the roller surface of the feeding roller, and boundaries of the separation pad holding member with respect to the separation pads are provided on both sides of the boundary of the rubbing member. The sheet feeding apparatus according to claim 7, wherein a width of a boundary between the rubbing members is narrower than a width between the roller members. In an image forming apparatus having recording means for recording an image on a sheet to be recorded,
An image forming apparatus comprising the sheet feeding device according to claim 1 as a sheet feeding device that feeds a sheet toward the recording unit. In an image reading apparatus having reading means for reading an image of a sheet to be read,
An image reading apparatus comprising the sheet feeding apparatus according to claim 1 as a sheet feeding apparatus that feeds a sheet toward the reading unit.

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