JP2003276869A - Paper feeder and image formation device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve deformation and damage to the upper tip part of a paper bundle by violently abutting on a paper feed roller peripheral surface when setting the paper bundle on the bottom plate of the paper feed tray and to feed the paper without any difficulty by suppressing curl even if the paper tip part is often curled in the paper feeder wherein the paper feed direction from the paper feed tray and the paper feed tray installation direction orthogonally cross with each other and the bottom plate, the paper feed roller, and a separation means are equipped in the paper feed tray side. <P>SOLUTION: This paper feeder is provided with the paper feed tray 1 detachably attached in the direction orthogonal to the paper feed direction and the paper feed roller 4. This paper feeder is also provided with a protection member 10 interposed between the paper feed roller and the bottom plate 2, when the paper feed tray is drawn out from the installation position in the device body, and covering a part of the outer circumference of the paper feed roller. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a sheet feeding device provided in an image forming apparatus such as a copying machine, a printer or a facsimile machine, and more particularly to a sheet feeding / removing sheet feeding / detaching direction. The present invention relates to an improved paper feed roller protection structure in a paper feed device having a paper tray.

[0002]

2. Description of the Related Art As a sheet feeding device which is installed in an image forming apparatus such as a copying machine, a printer or a facsimile machine and which feeds a sheet of paper to an image forming section, it is orthogonal to the direction of feeding the accommodated sheets of paper. There is known a so-called front loading type that includes a paper feed tray that is detachably attached in a pulling direction. In such a sheet feeding device, a pad separating method using a friction pad is used as a sheet separating unit when the uppermost sheet of the sheet bundle stored in the sheet feeding tray by the sheet feeding roller is fed. Further, there is a type in which the paper feed roller is incorporated in the paper feed tray side, and the drive means on the apparatus main body side and the shaft portion of the paper feed roller are connected in a state where the paper feed tray is attached to the apparatus main body. Are known. FIG. 6 is a view showing a mounting state of a sheet feeding tray in a conventional front loading type sheet feeding device, in which the sheet feeding tray 1 is moved in a direction orthogonal to a sheet surface along guides 7 and 8 provided on the apparatus main body side. By doing so, it becomes possible to attach / detach to / from the apparatus main body. The paper feed tray 1 is provided with a bottom plate 2 for loading sheets, which is supported by a shaft 2a in a tray body 1a so as to be vertically movable. The bottom plate 2 is biased upward by an elastic member 3. Further, a paper feed roller 4, a separation portion (separation pad) 5, and a separation spring (separation pad urging spring) 6 are arranged at the end of the tray body 1a in the paper feed direction. Reference numeral 9 is a paper guide on the apparatus main body side.

By the way, when the paper P on the bottom plate 2 is used up and the like, when the paper feed tray 1 is pulled out from the main body of the apparatus and the paper stack P is replenished on the bottom plate, it is supplied from the direction A. When the sheet bundle is pushed onto the bottom plate, the upper end of the sheet bundle collides with or is caught by the paper feed roller 4, which often causes the sheets located at the upper end of the sheet bundle to be damaged or deformed. If the paper is fed in this state, the leading edge of the paper is likely to be broken or torn, and further, jams, image defects and the like due to these factors are likely to occur. Further, the damage due to the collision with the sheet feeding roller when the sheet bundle is set may be aggravated when the leading end portion of the sheet bundle has a curl tendency. Japanese Patent Laid-Open No. 11-01170
Japanese Patent Laid-Open Publication No. 6-63 discloses that in a large-volume sheet feeding device juxtaposed to the side of an image forming apparatus main body, a sheet pressing member is provided on a lower surface of a cover that opens and closes an upper opening of a box-shaped sheet feeding apparatus housing, A technique is disclosed in which the upper surface of the sheet is suppressed by the pressing member at the time of closing to correct the curl that causes the sheet feeding failure by the sheet feeding roller. However, the technique described in this publication is
It does not prevent damage to the paper due to the paper bundle colliding with the paper feed rollers provided in the same paper feed tray, but presses the curl deformation part of the large amount of paper stack stacked in the paper feed device to feed It is just a solution to the problem of time. Therefore, there is no room for providing the cover and the sheet pressing member provided on the cover in the front loading type sheet feeding device. Further, since the pressing member provided on the cover can press only the upper surface of the sheet located on both sides of the sheet feeding roller that avoids the sheet feeding roller, when there is curl in the central portion of the sheet upper surface contacting the sheet feeding roller. There is a possibility that a paper feed failure may occur due to the influence of curl.

In Japanese Utility Model Registration No. 2560705 “Paper Feed Roller Cover Device”, a paper feed roller cover for protecting the paper feed roller from external light is manually moved to rotate along the roller surface. Techniques for activating are disclosed. That is, according to the technique described in this publication, when the cover is manually rotated to the roller concealing position, the tip of the pressing plate (bottom plate) that is close to the roller is held in the vicinity of the roller at the raised position, while When setting the stack of paper in
By retracting the cover in the roller opening direction, the pressing plate is pushed down against the urging spring, so that the setting can be performed. After setting the sheet bundle on the pressing plate, the cover is returned to the roller concealing position to unlock the pressing plate, and the pressing plate is elastically biased upward to press the upper surface of the sheet bundle against the sheet feeding roller. However, in this conventional example, the cover is retracted from the paper feed roller at the time of pushing down the pressing plate and setting the sheet bundle on the upper surface of the pressing plate.
The sheet bundle easily collides with the exposed surface of the sheet feeding roller. Therefore, it is not possible to prevent damage to the sheet bundle.
Even if a cover of this type is used to cover the surface of the paper feed roller when the paper is set, damage will occur due to the paper bundle colliding with the cover. Even if the cover is made of a low-friction material to prevent damage during a collision,
The method of manually opening and closing the cover causes a problem that the desired effect cannot be obtained when the device user forgets to operate the cover. In addition, Japanese Patent Laid-Open No. 2001-26
Japanese Patent No. 325 discloses a structure of a cover for covering a sheet feeding roller, and discloses a configuration in which a bottom plate, a sheet feeding means, a separating member and the like are provided on a sheet feeding table (sheet feeding tray). There is no mention of any measure for preventing damage to the paper that occurs when the paper comes into contact with the paper feed roller.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above, and the direction of paper feeding from the paper feeding tray is orthogonal to the paper feeding tray mounting direction, and the bottom plate is provided on the paper feeding tray side.
In a sheet feeding device equipped with a sheet feeding roller and a separating means, when the sheet bundle is set on the bottom plate of the sheet feeding tray, the upper end of the sheet bundle is strongly contacted with the peripheral surface of the sheet feeding roller to be deformed or damaged. You can solve the problem,
Another object of the present invention is to provide a sheet feeding device that can replenish the sheet without trouble even if the leading edge of the sheet has a curl, and an image forming apparatus using the sheet feeding device.

[0006]

In order to solve the above-mentioned problems, the invention of claim 1 provides a paper feed tray detachably mounted in a direction orthogonal to the paper feed direction in the apparatus main body, and the paper feed tray. In a paper feeding device having a bottom plate for mounting a paper, which is provided so as to be able to move up and down, and a paper feed roller for feeding the paper on the top face by rotating in contact with the top face of the paper on the bottom plate, A protective member is provided between the paper feed roller and the bottom plate to cover a part of the outer circumference of the paper feed roller when the paper feed tray is pulled out from the mounting position in the apparatus main body. The front loading type paper feeder is
It is used in various image forming apparatuses, and most of them have a paper feed roller on the paper feed tray side. When such a paper feed tray is pulled out from the main body of the apparatus and a stack of paper is replenished on the bottom plate, the upper end of the stack of paper hits the lower part of the peripheral surface of the paper feed roller, which may cause deformation or damage to the paper. There is.
Further, when the paper portion in contact with the paper feed roller has a curl or the like, collision with the paper feed roller causes deformation and damage, which further increases the risk of defective paper feed. According to the present invention, in the paper feeding device having the paper feeding tray, the bottom plate, the paper feeding roller, and the separating means, a part of the outer periphery of the paper feeding roller is covered, and the paper feeding roller and the bottom plate are covered when the paper feeding tray is pulled out. Since a protective member that moves in between is provided, the sheet bundle does not directly hit the sheet feed roller when the sheet bundle is set, the leading edge of the sheet does not break or break, and the curl of the sheet can be suppressed. .
According to a second aspect of the present invention, in the first aspect, the protection member is made of POM or other sliding material. According to the present invention, since the protective member is made of a sliding material (low friction material) typified by POM or the like, it is possible to prevent an abnormal sound of the sliding portion caused by the rotation of the sheet feeding roller. You can Further, the slidability of the surface of the protective member is improved, and the effect of preventing the leading edge of the sheet from being bent when the leading edge of the sheet hits the protective member is improved.

According to a third aspect of the present invention, in the first or second aspect, the protection member includes an engaging portion that is rotatable with respect to the shaft portion of the sheet feeding roller and is detachably engaged in the outer diameter direction. It is characterized by having. According to the present invention, since the protective member is provided with the engaging portion that can be attached / detached in the direction orthogonal to the center of the sheet feeding roller, the protective member can be easily removed when cleaning or replacing the sheet feeding roller. The cleanability and exchangeability of are improved. According to a fourth aspect of the present invention, a paper feed tray that is detachably mounted in a direction orthogonal to the paper feed direction in the apparatus main body, and a bottom plate for mounting a paper sheet that is vertically movable in the paper feed tray, A paper feeding device having a paper feed roller for feeding the uppermost paper by rotating in contact with the uppermost surface of the paper on the bottom plate, wherein the paper feed tray side is provided along the outer peripheral surface of the paper feed roller. A protective member that rotates in the circumferential direction and covers a part of the outer peripheral surface of the sheet feeding roller; and an elastic member that biases the protective member in a direction in which the protective member is interposed between the sheet feeding roller and the bottom plate. The apparatus main body side is provided with a sliding guide portion that abuts against the protection member and rotates it in the retreating direction when the paper feed tray is mounted in the apparatus main body. According to the present invention, the sliding guide portion having a plurality of surfaces is arranged on the apparatus main body side, and the protective member is rotated in the opening direction of the cover portion by making contact with a part of the protective member when the paper feed tray is mounted. Since it is configured so that the cover portion of the protection member can be moved forward and backward from the surface of the paper feed roller in conjunction with the attachment / detachment operation of the paper feed tray, the rotation of the protection member can be performed regardless of the user's operation. It is possible to prevent problems caused by forgetting the operation. An image forming apparatus according to a fifth aspect of the present invention includes a sheet feeding device according to any one of the first to fourth aspects, an image forming unit that forms an image on a sheet fed from the sheet feeding device, and a reading unit. It is characterized by including a unit and a writing unit. According to this, since the image forming apparatus is equipped with the sheet feeding device having the function described in each of the above claims, it is possible to form an image on a sheet without deformation or damage and improve the image quality. Further, it is possible to prevent the occurrence of paper jam due to deformation or damage.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration and operation of a sheet feeding device according to an embodiment of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 is a front vertical sectional view showing a main structure of a sheet feeding device according to a first embodiment of the present invention. A sheet feeding tray 1 is a rail provided in a sheet feeding device body (image forming apparatus body) not shown. Guided by 7 and 8, it is attached and detached in the front-back direction orthogonal to the paper surface. Inside the tray body 1a of the paper feed tray 1, a bottom plate 2 on which the paper P is placed and which rotates in the vertical direction about the shaft 2a, and a pressure spring 3 which presses the bottom plate 2 upward.
Is housed. At the front end of the tray body 1 a in the sheet feeding direction, a sheet feeding roller 4, a separating section 5 for separating the fed sheet into the sheet feeding roller 4 one by one, and a protection member 10.
And are provided. The separating portion 5 is pressed by a separating spring 6. The paper feed roller 4 has a shaft portion 4a.
Has a connecting portion (not shown) at one end thereof, and receives the transmission of the driving force by connecting with the connecting portion provided in the drive device of the apparatus when the feeding tray is completely mounted in the apparatus main body. Is configured. In the above configuration, the operation of feeding a sheet from the sheet feed tray 1 will be described. The bottom plate 2 in the sheet feed tray 1 is pushed up by the pressure spring 3 at the same time when the sheet feed tray 1 is inserted into the apparatus main body. Then, the upper surface of the bundle of sheets P on the bottom plate is fed by the feed roller 1.
Abutted against. On the other hand, the separating portion 5 is also brought into contact with the sheet feeding roller 4 by the separating spring 6. Then, a driving device (not shown) is connected to the shaft portion 4a of the sheet feeding roller, and the sheet is fed to the image forming unit on the image forming apparatus side along the guide plate 9 by the sheet feeding roller 4 which is rotationally driven. Further, a characteristic configuration of the first embodiment of the present invention will be described based on FIGS. 1 and 2. A protection member 10 is rotatably provided on a shaft portion 4a, which is driven and transmitted by a drive device (not shown) provided on the apparatus body side. The protection member 10 has a cover portion 15 having an arc-shaped plate surface that covers a part of the outer peripheral surface of the paper feed roller 4.
And a fan-shaped engaging portion 16 formed by bending from both ends of the cover portion 15, respectively, and a hole 16 provided in the engaging portion 16.
a is fitted to the shaft portion 4a. When the cover portion 15 of the protection member 10 is moved between the paper feed roller 4 and the bottom plate 2 when replenishing the bottom plate 2 with the paper feed tray pulled out of the machine, the leading end of the sheet bundle is protected. Since it hits the member 10, it does not hit the peripheral surface of the paper feed roller 4 directly. The surface of the protective member 10 is set to have a lower frictional resistance than the paper feed roller 4, so that the leading edge of the paper is not damaged even if the paper hits.

Next, in the sheet feeding device according to the second embodiment of the present invention, the engaging portion 16 of the protective member 10 is made of a sliding material (low friction material) typified by POM or the like. Therefore, the abnormal sound of the sliding portion generated between the shaft portion 4a and the hole 16a of the engaging portion is prevented. Also, by forming the cover portion 15 from the same material, the slidability of the surface of the cover portion is improved, and the effect of preventing the leading edge of the sheet from being bent when the leading edge of the sheet hits the surface of the cover portion 15 is improved. Next, FIG. 3 is a perspective view showing a main configuration of a sheet feeding device according to the third embodiment of the present invention. The cover portion 15 of the protection member 10 is rotatably engaged with the shaft portion 4a by the engagement portion 16. Hole 16a of engaging portion 16
A cutout portion 16b is provided in a part of the outer circumference of the shaft, and is removable in a direction orthogonal to the shaft portion 4a. As a result, the protective member 10 can be easily removed at the time of cleaning and replacing the paper feeding roller, and the cleaning property and the replaceability of the paper feeding roller 4 are improved.

Next, FIGS. 4 (a), (b) and (c) are a perspective view showing a structure of a fourth embodiment of the present invention and a cross-sectional view of an essential part. The characteristic configuration of this embodiment is that, on the side of the paper feed tray 1, the protective member 1 rotates in the circumferential direction along the outer peripheral surface of the paper feed roller 4 and covers a part of the outer peripheral surface of the paper feed roller 4.
0 and an elastic member (screw coil spring) 17 for urging the protective member 10 in the direction in which the protection member 10 is interposed between the sheet feeding roller 4 and the bottom plate 2, while the sheet feeding device main body (image forming apparatus main body) side is provided. 2 is provided with a slide guide portion 21 that abuts on the protection member 10 and rotates it in the retreating direction in the process of mounting the paper feed tray 1 in the apparatus main body. A connecting portion 4A that is connected to a connecting portion on the apparatus main body side is provided at the rear end of the shaft portion 4a of the sheet feeding roller 4, and by connecting both connecting portions, a driving force from a drive device on the apparatus main body side is provided. Is the shaft 4a
To be rotationally driven. That is, the protective member 10 includes a cover portion 15 that covers a part of the paper feed roller 4,
The support portion 1 that is connected to the cover portion 15 and extends in the axial direction.
0A and an operating protrusion (rotating lever) 10B protruding from a proper place on the outer periphery of the supporting portion 10A. Elastic member 17
By constantly energizing the protective member 10 as a whole in the counterclockwise direction about the shaft portion 4a, the cover portion 15 causes the lower portion of the surface of the sheet feeding roller (when the sheet bundle is set as shown in FIG. 4B). It is configured to close the collision site). In this state, when the sheet bundle P is set on the bottom plate 2, the upper end of the sheet bundle comes into contact with the cover portion 15 made of a material having a small friction resistance and does not come into contact with the roller surface, so that the sheet side is deformed. And there is no danger of being damaged. A sliding guide portion (sliding rail) 21 fixedly protruding from the sheet feeding device main body side has a tip portion bent in a crank shape, and has a first guide surface 2 parallel to the attachment / detachment direction of the sheet feeding tray.
1a and a second guide surface 21b inclined toward the back,
Third guide surface 21c parallel to the first guide surface 21a
And are equipped with. Further, the first guide surface 21a is provided with a sheet, as shown in FIG.
While slidingly contacting the operating protrusion 10B at the positions (a) and (b), the operating protrusion 10B is brought into contact with the second guide surface 21b and the third guide surface 21.
Guide to c sequentially. Therefore, the protective member 10 resists the elastic member 17 from the closed state of FIG. 4B to the state of FIG.
To the open state, and in (c), the cover portion 15 which has been closing the lower surface of the paper feed roller until then is retracted upward and the lower surface of the roller is held in the open state. Is brought into contact with the upper end of the leading edge of the sheet bundle P to make it ready for feeding. When the paper feed tray 1 is pulled out, the operating protrusion 10B moves along each guide surface through a path opposite to that when the paper feed tray 1 is mounted. Therefore, when the paper feed tray 1 is completely pulled out, the cover of the paper feed roller surface may be hidden. it can.

Next, the operation of the fourth embodiment will be described. When replenishing paper, the bottom plate 2 in the paper feed tray 1 is pushed down, and the bottom plate 2 is locked in a pushed down state by a locking means (not shown). At this time, the protective member 10 moves the cover portion 15 to the sheet feeding roller 4 by the urging force of the elastic member 17.
And the bottom plate 2 are moved and held (FIG. 4B).
After replenishing the bottom plate 2 with paper in this state, the paper feed tray 1
When the sheet is inserted into the main body of the sheet feeding device, the operating protrusion 10B of the protection member 10 causes the guide surfaces 21a, 21a of the sliding guide portion 21 to move.
b and 21c are sequentially contacted and slid to rotate the protection member 10 integrated with the operation protrusion 10B in the direction opposite to the rotation direction of the paper feed roller 4 to open the lower surface of the paper feed roller 4 (Fig. 4 (b)). Therefore, the lower surface of the paper feed roller 4 and the upper portion of the sheet bundle are brought into contact with each other, and the sheet can be fed. By the above operation, even if the user does not manually operate the protection member 10, the protection member is retracted from the surface of the paper feed roller in association with the operation of mounting the paper feed tray 1 in the apparatus main body.
FIG. 5 is a schematic diagram showing an example of the configuration of an image forming apparatus provided with a sheet feeding device of the present invention. This image forming apparatus includes a sheet feeding device A, an image forming section B, a writing unit C, a reading unit D,
And a copying machine or a printer equipped with a sheet feeding device E. By applying the sheet feeding device A of the present invention to this image forming apparatus, the sheet is not deformed or damaged due to the collision between the sheet feeding roller and the sheet and the sheet being caught, and the sheet is curled. With respect to the paper having the leading edge, it can be pressed down so that the paper feeding can be prevented. It should be noted that the present invention can be applied to a facsimile, and can also be applied to other general devices including a paper feeding device for feeding paper.

[0012]

As described above, according to the present invention, the paper feed direction from the paper feed tray is orthogonal to the paper feed tray mounting direction, and the bottom plate, the paper feed roller, and the separating means are provided on the paper feed tray side. In the paper feeding device, it is possible to solve the problem that when the paper bundle is set on the bottom plate of the paper feed tray, the upper end of the paper bundle is strongly contacted with the peripheral surface of the paper feed roller to be deformed or damaged. Further, even if there is a curl tendency at the leading end of the sheet, the curl can be suppressed and the sheet can be fed. According to the invention of claim 1, in the front loading type sheet feeding device having the sheet feeding roller on the side of the sheet feeding tray, when the sheet feeding tray is pulled out, it is moved between the sheet feeding roller and the bottom plate to protect the roller surface. Since the member is provided, the sheet bundle does not directly contact the sheet feeding roller when the sheet bundle is set, the leading edge of the sheet is not broken or broken, and the curl of the sheet can be suppressed. According to the invention of claim 2, since the protective member is made of a sliding material (low friction material) typified by POM or the like, an abnormal sound of the sliding portion caused by the rotation of the sheet feeding roller is generated. Can be prevented. Further, the slidability of the surface of the protective member is improved, and the effect of preventing the leading edge of the sheet from being bent when the leading edge of the sheet hits the protective member is improved. According to the third aspect of the present invention, since the protective member is provided with the engaging portion that can be attached / detached in the direction orthogonal to the center of the sheet feeding roller, the protective member can be easily removed when cleaning or replacing the sheet feeding roller. Improves cleaning and exchangeability of the paper feed roller. According to the invention of claim 4, a sliding guide portion having a plurality of guide surfaces is arranged on the apparatus main body side, and each guide surface is sequentially brought into contact with a part of the protection member when the paper feed tray is mounted to protect the same. Since the member is configured to rotate in the opening and closing directions of the cover part, the cover part of the protective member can be moved forward and backward from the surface of the paper feed roller in conjunction with the attachment / detachment operation of the paper feed tray. The protective member can be rotated regardless of the presence or absence of the operation, and a defect due to forgetting the operation can be prevented. According to the image forming apparatus of the fifth aspect, since the image forming apparatus is equipped with the sheet feeding device, it is possible to form an image on a sheet without deformation or damage, and it is possible to improve the image quality. Further, it is possible to prevent the occurrence of paper jam due to deformation or damage.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a main configuration of a paper feeding device according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing a main configuration of the paper feeding device of FIG.

FIG. 3 is a perspective view showing a main part of a second embodiment of the present invention.

FIG. 4A is a perspective view showing a main part of a third embodiment of the present invention, and FIGS. 4B and 4C are cross-sectional views of the main part.

FIG. 5 is a schematic configuration diagram of an image forming apparatus to which the present invention is applied.

FIG. 6 is a diagram showing a mounted state of a paper feed tray in a conventional front loading type paper feeder.

[Explanation of symbols]

1 paper feed tray, 2 bottom plate, 4 paper feed rollers, 7, 8
Rail, 10 protection member, 10A supporting portion, 10B actuating protrusion, 15 cover portion, 16 engaging portion, 16a hole, 1
6b Notch part, 17 Elastic member (screw coil spring), 21 Sliding guide part, 21a, 21b, 21c
Guide surface.

Claims (5)

[Claims] 1. A paper feed tray detachably mounted in a direction orthogonal to the paper feed direction in the main body of the apparatus, a bottom plate for loading and unloading paper provided in the paper feed tray, and a bottom plate on the bottom plate. A sheet feeding roller for feeding the uppermost sheet of paper by rotating in contact with the uppermost sheet of the sheet of paper, the sheet feeding roller when the sheet feeding tray is pulled out from a mounting position in the apparatus body. And a bottom plate interposed between the bottom plate and the bottom plate to cover a part of the outer circumference of the paper feed roller. 2. The PO according to claim 1, wherein the protective member is made of PO.
A sheet feeding device comprising M and other sliding materials. 3. The protective member according to claim 1 or 2, wherein the protection member includes an engaging portion that engages with a shaft portion of the sheet feeding roller so as to be rotatable and detachable in an outer diameter direction. Characteristic paper feeding device. 4. A paper feed tray detachably mounted in a direction orthogonal to the paper feed direction in the main body of the apparatus, a bottom plate for loading and unloading the paper provided in the paper feed tray, and on the bottom plate. A sheet feeding device that feeds the uppermost sheet of paper by rotating in contact with the uppermost sheet of the sheet, A protection member that rotates in a direction and covers a part of the outer peripheral surface of the paper feed roller; and an elastic member that biases the protection member in a direction in which the protection member is interposed between the paper feed roller and the bottom plate. The sheet feeding device is characterized in that a slide guide portion is provided on the side for abutting against the protection member and rotating the protection member in the retracting direction in the process of mounting the paper feeding tray in the apparatus main body. 5. The sheet feeding device according to claim 1, an image forming unit that forms an image on a sheet fed from the sheet feeding device, a reading unit, and a writing unit. An image forming apparatus comprising: