JPH10167482A - Sheet feeding device and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air separation type sheet feeding device capable of accurately separating each sheet. SOLUTION: A sheet tray 53 is provided with each side wing part 53a at both its sides while being made to form an angle of α. Meanwhile, the aforesaid sheet tray is provided with a transit wing 52 at its rear end side while being made to from an angle of β, and with a rear end restricting plate 51. The transit wing 52 is provided with a plane 53b (angle of β) whose position is higher in height with respect to a plane 5 roughly at the central part of the sheet tray 53 as it goes to upstream side in the feeding direction. The peripheral parts (both sides and rear end part) of a sheet loaded on the sheet tray 53, are kept higher is position than its central part by means of the side wings 53a and the transit wing 52. Therefore, sealing performance at the peripheral parts between the sheets is kept high. As a result, since air injected out of a separating device 35, flows uniformly in a space between the lowermost sheet and a sheet right above the aforesaid sheet, excellent separating properties can be thereby be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet feeder used for an image forming apparatus such as a copying machine, a laser beam printer, and the like, and an image forming apparatus having the same.

[0002]

2. Description of the Related Art An example of a conventional automatic document feeder using a vacuum suction belt will be described with reference to FIGS.

A document tray 32 on which documents 31 are stacked is
In order to prevent the second and subsequent documents from being double fed, as shown in FIG. 10, the document is inclined by a predetermined angle θ so that the downstream side in the transport direction is positioned higher than the upstream side in the transport direction. Is common. Then, the original is placed on the rear end regulating plate 4.
The document is placed on the document tray 32 in a state where the document abuts on the document tray 32.

A notch 34 is provided at the center of the front portion of the document tray 32 (see FIG. 11). A rubber belt 35 having a large number of holes 36 is provided in the notch 34. As shown in FIG. 10, a vacuum box 37 connected to a blower is provided on the back surface (inside the track) of the belt 35. Therefore, the blower is operated to open the hole 3 through the vacuum box 37.
By sucking air from the document 6, the lowermost document among the documents stacked on the document tray 32 can be attracted to the belt 35. Then, by rotating the belt 35 in the state as it is, the original that has been attracted is sent out in the rotation direction of the belt 35.

[0005] A large number of outlets 39 for blowing air obliquely downward are provided in a separating device 38 provided above the front end of the belt 35. The separation device 38
Is the lowermost document 31 taken out by the belt 35
When air is blown out from the outlet 39 between the sheet and a stack (another sheet) thereon, when two originals are taken out in a stacked state, they are separated and only the lower one is sent out. .

The document tray 32 is provided with a wing member 29 to assist such a separating action by blowing air. By raising the left and right sides of the document by the wing member 29, an air layer is easily formed between the sucked document and the stack thereon.

[0007]

However, the conventional document feeder has the following problems. In other words, the space between both sides of the document and the document tray 32 is in a closed state (a state with high sealability) due to the presence of the wing member 29. Therefore, the separation nozzle 39
Air (not shown) flows between the lowermost document 30 adsorbed on the belt 35 and the document 31 thereon as shown by an arrow D in FIG. 12 to form an air layer.

However, since air easily escapes from the rear end of the document, pressure concentrates on both sides of the document,
There is a problem that double feed is likely to occur. In order to solve such a problem, for example, US Pat.
The tray shape as shown in the figure is also shown.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an air separation type sheet feeding apparatus in which a floating state of a sheet is uniform, a good seal is obtained on both sides and a rear part of the sheet, and double feeding does not occur. I do.

[0010]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above object. As a first aspect, the present invention comprises sheet stacking means for stacking sheets, and a suction section.
A suction conveyance unit that suctions and transports the lowermost sheet of the sheets stacked on the sheet stacking unit to the suction unit, and blows air from the front to a lower part of the sheet group stacked on the sheet stacking unit. A sheet separating unit that separates the lowermost sheet stacked on the sheet stacking unit from another sheet on the lowermost sheet, wherein the sheet stacking unit includes a sheet stacking unit on which a sheet is stacked. A stacking surface component having a surface, and a rear end seal member disposed on the sheet stacking surface, having an inclined surface whose position with respect to the sheet stacking surface increases as going downstream in the sheet conveyance direction, Is provided.

It is preferable that the position of the trailing end seal member in the transport direction on the sheet stacking surface can be changed.

The sheet stacking means further includes a rear end regulating member for regulating a rear end of the sheet stacked on the sheet stacking surface, and the rear end sealing member and the rear end regulating member are integrated. It is preferred that

[0013] The sheet stacking means may further include side seal members disposed on the left and right sides of the sheet stacking surface, each of the side seal members having an inclined surface whose position with respect to the sheet stacking surface increases as the sheet stacks in the sheet conveying direction. It is preferred to have.

[0014] The side seal member may be integrated with the loading surface constituting member.

According to a second aspect of the present invention, there is provided an image reading unit which includes a document table and reads an image of a document placed on the document table, and sequentially transports a separately prepared document to the document table. A sheet feeding device according to a first aspect, a sheet feeding unit for feeding a sheet on which an image is formed, and an image forming unit for forming an image read by the image reading unit on a sheet fed by the sheet feeding device And an image forming apparatus characterized by having the following.

The operation will be described.

The rear end sealing member keeps the rear portion of the sheets stacked on the sheet stacking surface higher than the sheet stacking surface. Thereby, the sealing property between the sheets at the rear end of the sheet is enhanced. On the other hand, the side seal member
Improve the sealing performance on the left and right sides of the seat. Thus, the air blown by the sheet separating means spreads evenly between the lowermost sheet and the sheet above the lowermost sheet, thereby improving the separating property.

Incidentally, if the position of the sealing rear sealing member is changed according to the size of the sheet, the separating property can be surely enhanced even for sheets of various sizes.

The side seal member and the loading surface constituting member are
Further, if the rear end sealing member and the rear end regulating member are integrated, the device can be simplified.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. [First Embodiment] As shown in FIG. 2, a sheet feeding apparatus according to this embodiment includes a sheet tray 53, a sheet tray 5
3, a suction conveyance device 1 arranged downstream in the sheet feeding direction.
00, a separating device 38, and a rear end regulating plate 51.

The sheet tray 53 is for stacking sheets. The sheet tray 53 is inclined rearward as shown in FIG. 2 to increase the efficiency of the apparatus. This tilt angle θ ranges from about 1 ° to about 15 °. The sheet tray 53 has side wing portions 53a on both sides in a direction perpendicular to the sheet conveying direction, which are provided with an angle α (= 1 to 10 degrees) with respect to a central plane 53b of the sheet tray 53. Is provided. Also,
A cutout 70 is provided at a central portion on the upstream side of the sheet tray 53 in parallel with the sheet feeding direction (see FIG. 1). This notch 7
Numeral 0 is used to attach the rear end regulating plate 51 to the sheet tray 53.

The trailing edge regulating plate 51 regulates the trailing edge of the stacked sheets. The rear end regulating plate 51 is
As shown in FIG. 2, the sheet tray 53 is provided perpendicularly to the sheet tray 53 at a position corresponding to the upstream side in the sheet feeding direction of the sheet tray 53. Further, it is configured to be movable as shown by an arrow C in the paper feeding direction. By appropriately changing the position of the rear end regulating plate 51, it is possible to cope with various sheet sizes. The specific mounting structure of the rear end regulating plate 51 to the sheet tray 53 is as follows. The bottle 72 protruding from the bottom of the rear end regulating plate 51 is moved to the sheet tray 53.
The rear end regulating plate 51 is attached to the sheet tray 53 so as to be able to move parallel to the sheet tray 53 by inserting the nut into the notch 70 and attaching the nut.

Further, the rear end regulating plate 51 of this embodiment is
A transition wing 52 is provided downstream of the sheet feeding direction (see FIGS. 1 and 2). As the transition wing 52 moves toward the upstream side in the sheet feeding direction, the central plane 53b of the sheet tray 53
Is provided with a plane portion at which the position of The angle β of the transition wing 52 with respect to the central plane 53b is about 1
° to 10 °. Transition wing 52 and rear end regulating plate 5
1 is formed integrally. Therefore, the rear end regulating plate 51
Is slid to change the position in the transport direction, the transition wing 52 is also slid in conjunction with this to change the position in the transport direction.

The suction conveyance device 100 is for suctioning and conveying a sheet. As shown in FIG. 2, the suction conveyance device 100 includes a suction chamber 58 having a suction opening 58a at an upper part thereof as a mechanism for sucking the lowermost sheet among the sheets stacked on the sheet tray 53.
And a suction blower 57 connected to the suction chamber 58. The suction chamber 58 is arranged such that the suction opening 58 a is substantially parallel to the sheet tray 53. Therefore, by operating the suction blower 57 and sucking air through the suction chamber 58 and the suction opening 58a, the lowermost sheet is adsorbed on the transport belt 56 (described later) in a region corresponding to the adsorbing section A. Has become.

The suction conveyance device 100 further includes a suction chamber 5 as a mechanism for conveying the suctioned sheet.
, A conveying belt 56 arranged to cover the suction opening 58a, rollers 54 and 55 for supporting the conveying belt 56,
And a motor (not shown) for driving the motor 5. The transport belt 56 is configured to be rotated in the direction of arrow B by the rollers 55. The transport belt 56 has a plurality of suction holes 56a.

The separation device 38 injects air,
This is to help separate the sheets. The separation device 3
Specifically, the blower 8 includes a blower blower (not shown) and an air blowing nozzle 60 that sprays an air flow supplied from the blower blower. The direction of ejection by the air blowing nozzle 60 is set such that the ejected air hits the upper surface of the suction section A from above the downstream side of the sheet tray 53, that is, the tip of the lowermost sheet. The plurality of air blowing nozzles 60 are provided at positions corresponding to the suction area of the transport belt 56 in the sheet width direction.

In the present embodiment, the “sheet stacking means” referred to in the claims is a sheet tray 53,
The rear end regulating plate 51 corresponds to the transition wing 52. Especially,
The “stacking surface component member” corresponds to a central portion of the sheet tray 53. “Sheet loading surface” refers to the sheet tray 53.
Corresponds to the central plane 53b. The “rear end sealing member” corresponds to the transition wing 52. The “rear end regulating member” corresponds to the rear end regulating plate 51. "Side seal member"
"" Corresponds to the side wing portion 53a. The “suction conveyance unit” corresponds to the suction conveyance device 100. “Sheet separating means” corresponds to the separating device 38.

The operation will be described.

The user adjusts the position of the trailing edge regulating plate 51 in accordance with the size of the sheets to be stacked so that the trailing edge of the stacked sheets abuts on the trailing edge regulating plate 51. After the position adjustment, the sheets are stacked on the sheet tray 53.

When the sheet feeding is started, first, the suction blower 57 and the blower blower (not shown) are operated.

The suction blower 57 sucks air through the suction opening 58a and the suction hole 56a. Then, the lowermost sheet among the sheets stacked on the sheet tray 53 is attracted to the transport belt 56 by the suction force.

On the other hand, the air (air) sent from the blowing blower (not shown) is guided to an air blowing nozzle 60 through a blowing duct (not shown), and is sprayed from the nozzle 60 toward the front end of the sheet.

The injected air is supplied to the lowermost sheet S
1 and the other sheet S, the pocket 71
Is formed (see FIGS. 4 and 5). In this case, in the present embodiment, since the sheet tray 53 is provided with the side wing portions 53a and the transition wings 52, the pockets 71 are easily and reliably formed. In other words, the side wing portions 53a and the transition wings 52 lift the edges of the lowermost sheet S1, so that the side wing portions 53a
A good seal is formed between the lowermost sheet S1 adsorbed around the transition wing 52 and the other sheets S. By forming such a good seal, a high pressure is generated between the lowermost sheet S1 and another sheet, and the pocket 71 is reliably formed. Then, by the formation of the pocket 71, the air blown out from the air blowing nozzle 60 flows uniformly to the sheet (see FIG. 6), and stably floats the sheet.

Thereafter, the sucked lowermost sheet S1 is
It is transported by the transport belt 56.

In the embodiment described above, the sucked lowermost sheet S1 and the other sheets S are well sealed not only on both sides but also on the rear. Therefore, a very stable floating of the sheet S can be secured. Therefore, when the lowermost sheet S1 is conveyed, it can be conveyed with a very small load.

In this embodiment, the side wing portions 53a
Is formed integrally with the main body portion (center portion) of the sheet tray 53. However, both need not necessarily be formed integrally. Also, the rear end regulating plate 51 and the transition wing 5
Similarly, it is not always necessary to integrally form the second and the second. [Second Embodiment] As shown in FIGS. 7 and 8, a sheet feeding device of this embodiment
And a suction conveyance device 100 disposed downstream of the sheet tray 53 in the sheet feeding direction, a separation device 38, a rear end regulating unit 80, and a sheet abutment pad 81.

The sheet tray 53 is for stacking sheets. The sheet tray 53 is inclined backward as shown in FIG. 7 to increase the efficiency of the apparatus. This tilt angle θ ranges from about 1 ° to about 15 °. The sheet tray 53 has side wings on both sides in a direction perpendicular to the sheet conveying direction, which have an angle α (= 1 ° to 10 °) with respect to a central plane 53b of the sheet tray 53. 53a is provided (FIG. 8)
reference).

The trailing edge regulating unit 80 regulates the trailing edge of the stacked sheets and returns the once fed sheets to the sheet tray 53. The rear end regulating unit 80 is arranged on the upstream side of the sheet tray 53 in the sheet feeding direction. The rear end regulating unit 80 is configured to be movable in the paper feeding direction.
Specifically, a gear (not shown) provided on the bottom surface of the rear end regulating unit 80 moves the rack on the stacking tray 53 to realize the movement. In this case, the internal mechanism is moved together. By appropriately changing the position of the rear end regulating unit 80, it is possible to cope with various sheet sizes.

Among the functions of the above-mentioned rear end regulating unit 80, the sheet fed once is circulated to the sheet tray 53.
The mechanism for returning to the upper side (for example, the discharge roller 80b)
It is provided inside the rear end regulating unit 80.

On the other hand, the function of regulating the trailing edge of the sheet is performed by a trailing edge regulating plate 80a provided downstream of the trailing edge regulating unit 80 in the conveying direction. That is,
The trailing end of the stacked sheets is brought into contact with the trailing end regulating plate 80a to regulate it. Further, the rear end regulating plate 80a of the present embodiment includes a transition wing 52 on the downstream side in the sheet feeding direction. The transition wing 52 is provided with a plane portion in which the position with respect to the central plane 53a of the sheet tray 53 becomes higher toward the upstream side in the sheet feeding direction. The angle β between the transition wing 52 and the central plane 53a is about 1 °
From 10 °. Transition wing 52 and rear end regulating plate 80
a is formed integrally. Therefore, when the rear end regulating unit 80 is slid and its position is changed, the transition wing 52 is also slid and its position is changed.

The sheet abutting pad 81 is fed by the sheet feeding device, and thereafter, the rear end regulating unit 8
This is for stopping the sheet returned to the sheet tray 53 by 0. The sheet butting pad 81
Are arranged perpendicularly to the sheet tray 53 on the downstream side of the sheet tray 53 in the sheet feeding direction.
The surface is made of a member such as felt which absorbs sound.

The suction conveyance device 100 is for suctioning and conveying a sheet. As shown in FIG. 7, the suction conveyance device 100 includes a suction chamber 58 having a suction opening 58a at an upper part thereof as a mechanism for sucking the lowermost sheet among the sheets stacked on the sheet tray 53.
And a suction blower 57 connected to the suction chamber 58. The suction chamber 58 is arranged such that the suction opening 58 a is substantially parallel to the sheet tray 53. Therefore, by operating the suction blower 57 and sucking air through the suction chamber 58 and the suction opening 58a, the lowermost sheet is adsorbed on the transport belt 56 (described later) in a region corresponding to the adsorbing section A. Has become.

The suction conveyance device 100 further includes a suction chamber 5 as a mechanism for conveying the suctioned sheet.
, A conveying belt 56 arranged to cover the suction opening 58a, rollers 54 and 55 for supporting the conveying belt 56,
And a motor (not shown) for driving the motor 5. The transport belt 56 is rotated in the direction of arrow B by the rollers 55. The transport belt 56 has a plurality of suction holes 56a.

The separation device 38 injects air,
This is to help separate the sheets. The separation device 3
Specifically, the blower 8 includes a blower blower (not shown) and an air blowing nozzle 60 that sprays an air flow supplied from the blower blower. The direction of ejection by the air blowing nozzle 60 is set such that the ejected air hits the upper surface of the suction section A from above the downstream side of the sheet tray 53, that is, the tip of the lowermost sheet. The plurality of air blowing nozzles 60 are provided at positions corresponding to the suction area of the transport belt 56 in the sheet width direction.

The operation will be described.

The user adjusts the position of the trailing edge regulating unit 80 according to the size of the sheets to be loaded, so that the trailing edge of the stacked sheets abuts on the trailing edge regulating plate 80a.
After the position adjustment, the sheets are stacked on the sheet tray 53.

When the sheet feeding is started, first, the suction blower 57 and the blower blower (not shown) are operated.

The suction blower 57 sucks air through the suction opening 58a and the suction hole 56a. Then, the lowermost sheet among the sheets stacked on the sheet tray 53 is attracted to the transport belt 56 by the suction force.

On the other hand, the air (air) sent from the blowing blower (not shown) is guided to the air blowing nozzle 60 through a blowing duct (not shown), and is blown from there toward the leading end of the sheet.

The jet air is supplied to the lowermost sheet S
1 and the other sheet S, the pocket 71
Is formed (see FIG. 5). In this case, in the present embodiment, since the sheet tray 53 is provided with the side wing portions 53a and the transition wings 52, the pockets 71 are easily and reliably formed. That is, the side wing portion 53a
And since the transition wing 52 raises the edge of the lowermost sheet S1, the lowermost sheet S1 adsorbed around the side wing portion 53a and the transition wing 52.
And a good seal is formed between the sheet and the other sheets S. By forming such a good seal, a high pressure is generated between the lowermost sheet S1 and another sheet, and the pocket 71 is reliably formed. Then, by the formation of the pocket 71, the air blown out from the air blowing nozzle 60 flows uniformly to the sheet (see FIG. 6), and stably floats the sheet.

Thereafter, the sucked lowermost sheet S1 is
The sheet is conveyed to a reversing section (not shown) by the conveying belt 56. Thereafter, the sheet is sent to a rear end regulating unit 80 through a platen (not shown) of a copying machine or the like. Then, the sheet is discharged onto the sheet tray 53 by the discharge roller 80b of the rear end regulating unit 80. The discharged sheet flies over the sheet tray 53 and hits the sheet butting pad 81. Then, the sheet is stacked on the sheet tray 53 again.

In the embodiment described above, the sucked lowermost sheet S1 and the other sheets S are well sealed not only on both sides but also on the rear. Therefore, a very stable floating of the sheet S can be secured. Therefore, when the lowermost sheet S1 is conveyed, it can be conveyed with a very small load. [Third Embodiment]
The third embodiment is a copying machine provided with an automatic document feeder. In the present embodiment, the sheet feeding device of the first embodiment described above is employed as the automatic document feeding device. Hereinafter, the copying machine will be described with reference to FIG.

At the top of the copying machine main body 900, a document table 9
An automatic document feeder 901 for automatically supplying a document onto the document 06 is provided. As described above, in this embodiment, the automatic document feeder 901 employs the sheet feeder described in the first embodiment.

A light source 907, an optical system 908, a paper feeding unit 909, an image forming unit 902, and the like are provided in the copying machine main body 900. The image forming section 902 includes a cylindrical photoconductor 914, a developing device 915, a transfer charger 916, a separation charger 917, a cleaner 918, a primary charger 919, and the like. Downstream of the image forming unit 902, a transport device 920, a fixing device 904, a discharge roller pair 905, and the like are provided.

When a paper feed signal is output from control device 930 provided in copying machine main body 900,
A paper feed unit 909 is provided in a paper feed tray 910 or a cassette 911.
Feeds a sheet-like recording material from. The skew of the fed recording material is corrected by a pair of registration rollers 921. Further, the image forming unit 9 is synchronized with the timing of other mechanism units.
02.

On the other hand, the automatic document feeder 901 conveys the lowermost document among the documents (sheets) stacked on the tray to the document table 906. The details of the transfer are as described in the first embodiment.

When the document arrives at the document table 906, the light source 9
Reference numeral 07 irradiates light on the document D placed on the document table 906. The optical system 908 collects the reflected light on the cylindrical photoconductor 914. In this case, the photoconductor 914 is charged in advance by the primary charger 919. By irradiating the photoconductor 914 with light reflected from a document, an electrostatic latent image is formed on the photoconductor 914. The developing device 915 containing the toner forms a toner image on the photoconductor 914 according to the electrostatic latent image. Then, the transfer charger 91
6 transfers the toner image on the photoconductor 914 to the recording material sent. The separation charger 917 separates the recording material from the photoconductor 914 by charging the recording material onto which the toner image has been transferred to a polarity opposite to that of the transfer charger 916.

The conveying device 920 conveys the recording material separated from the photosensitive member 914 to the fixing device 904. The fixing device 904 permanently fixes the unfixed transfer image on the sheet. The discharge roller pair 905 discharges the recording material on which the image has been fixed to the outside of the copying machine main body 900.

In the copying machine of the third embodiment, the separation of the original is more reliable.

[0060]

As described above, in the sheet feeding apparatus and the image forming apparatus according to the present invention, the separation of the sheet by blowing the air is more reliable.

[Brief description of the drawings]

FIG. 1 is a perspective view of a sheet feeding apparatus according to a first embodiment of the present invention.

FIG. 2 is a side sectional view of the sheet feeding apparatus according to the first embodiment of the present invention.

FIG. 3 is a plan view of the sheet feeding device according to the first embodiment of the present invention.

FIG. 4 is a vertical sectional front view of the sheet feeding device according to the first embodiment of the present invention.

FIG. 5 is a schematic diagram showing a state of sheet separation by air.

FIG. 6 is a schematic diagram showing a flow of air.

FIG. 7 is a perspective view of a sheet feeding device according to a second embodiment of the present invention.

FIG. 8 is a plan view of a sheet feeding device according to a second embodiment of the present invention.

FIG. 9 is a diagram showing an internal configuration of a copying machine according to a third embodiment of the present invention.

FIG. 10 is a schematic side perspective view showing a conventional sheet feeding apparatus.

FIG. 11 is a perspective view showing a conventional sheet stacking tray.

FIG. 12 is a schematic diagram illustrating a flow of air in a conventional sheet feeding apparatus.

[Explanation of symbols]

 Reference Signs List 38 Separation device 51 Rear end regulating plate 53 Sheet tray 52 Transition wing 53a Side wing portion 56 Conveying belt 57 Suction blower 58 Suction chamber 60 Air blowing nozzle 72 Bottle portion 80 Rear end regulating unit 80a Rear end regulating plate 81 Sheet abutting pad 100 Suction transfer device

Claims (6)

[Claims] 1. A sheet stacking means for stacking sheets, a suction unit, comprising: a suction unit; and a suction conveyance unit for suctioning and conveying the lowermost sheet of the sheets stacked on the sheet stacking unit to the suction unit; Sheet separation for separating the lowermost sheet stacked on the sheet stacking unit from other sheets thereon by blowing air from the front to the lower part of the sheet group stacked on the sheet stacking unit Means, a sheet stacking member having a sheet stacking surface on which sheets are stacked, and an inclined surface whose position with respect to the sheet stacking surface increases as going downstream in the sheet conveying direction. And a rear end sealing member disposed on the sheet stacking surface, comprising: 2. The sheet feeding device according to claim 1, wherein the position of the rear end seal member in the transport direction on the sheet stacking surface is changeable. 3. The sheet stacking unit further includes a rear end regulating member that regulates a rear end of a sheet stacked on the sheet stacking surface, wherein the rear end sealing member and the rear end regulating member include: The sheet feeding device according to claim 2, wherein the sheet feeding device is integrated. 4. The sheet stacking means further includes side seal members disposed on the left and right sides of the sheet stacking surface having an inclined surface whose position with respect to the sheet stacking surface becomes higher as going left and right in the sheet conveying direction. The sheet feeding apparatus according to claim 1, 2, or 3, further comprising: 5. The sheet feeding device according to claim 4, wherein the side seal member is integrated with the loading surface constituting member. 6. An image reading unit comprising a document table, for reading an image of a document placed on the document table, and sequentially transporting a separately prepared document to the document table. Or a sheet feeding device for feeding a sheet on which an image is to be formed, and an image forming portion for forming an image read by the image reading means on a sheet fed by the sheet feeding device. An image forming apparatus comprising: