Sheet feeding device and image forming device

Abstract

To provide a sheet feeding device that is configured so that a shuffling-air blowing fan of a sheet feeding part moves together with a side regulating part, which is prevented from deteriorating in operability in moving the side regulating part.SOLUTION: A sheet feeding device is provided with: a shuffling-air blowing port for blowing shuffling air to a sheet arranged on a side regulating part of a sheet feeding part; a shuffling-air blowing fan for supplying shuffling air to the shuffling-air blowing port, which can move together with the side regulating part; a shuffling-air blowing fan-side duct, fixed to the shuffling-air blowing fan, which blows shuffling air supplied from the shuffling-air blowing fan to the shuffling-air blowing port of the side regulating part; and a side regulating part-side duct, fixed to the side regulating part, which is connected to the shuffling-air blowing fan-side duct with a predetermined movable space in order to blow shuffling air from the shuffling-air blowing fan-side duct to the shuffling-air blowing port of the side regulating part. An image forming device is used together with the sheet feeding device.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a sheet feeding device and an image forming apparatus capable of blowing handling air to a stack of sheets for handling the stack of sheets. [Background technology]

[0002] In recent years, electrophotographic image forming apparatuses such as copying machines, printers, and facsimiles have come to be popularized as colored and high-image-quality devices. Users of image forming apparatuses used in offices are also demanding print products with higher image quality and higher resolution.

[0003] Generally, the paper used in office image forming devices is often plain paper or recycled paper. However, there is a limit to how well plain paper can produce the required beautiful and attractive output. Therefore, in order to produce more beautiful and attractive output, special paper such as coated paper and thick paper is becoming more and more desirable.

[0004] Conventionally, in order to feed special paper in image forming apparatuses, manual feed devices attached to the side walls of the image forming apparatus have been used. This is because the manual feed device can be used for paper sizes that cannot be set in the cassette feed device inside the image forming apparatus (long paper, non-standard size paper, small size paper) and high-rigidity thick paper that has a large transport resistance and cannot be transported unless the transport path is straight.

[0005] Furthermore, it is recommended that only one sheet of coated paper be placed in the feeding tray. This is to prevent the sheets of coated paper from sticking to each other and ensure reliable feeding, but this can result in problems such as reduced productivity.

[0006] Therefore, Patent Document 1 proposes a configuration for feeding such coated paper, in which loosening air is blown onto the side edges of a sheet stack to reduce sticking between sheets. In the configuration of Patent Document 1, a loosening air blowing fan and a loosening air outlet for the loosening air generated by the loosening air blowing fan are provided on a side regulating plate that regulates the position of the sheets in the width direction, so that the loosening air is blown onto the side edges of the sheets to eliminate sticking between the sheets. By using such a configuration, it becomes possible to set multiple sheets of special paper and feed them continuously even from a manual feed device. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2006-256819 A Summary of the Invention [Problem to be solved by the invention]

[0008] On the other hand, since the side regulating plate moves to regulate the width direction of the stacked sheets, when the separating air blowing fan is moved together with the side regulating plate, if a guide member for guiding the movement of the separating air blowing fan in conjunction with the movement of the side regulating plate is provided separately from the guide member for guiding the movement of the side regulating plate, the movement positions of the side regulating plate and the separating air blowing fan may be misaligned with each other because the movement positions are regulated by separate guide members. If the movement positions are misaligned in this way, the side regulating plate will be twisted or bent as it moves, and a force will act to return the deformation, creating a large resistance when the user operates the side regulating plate, deteriorating operability.

[0009] The present invention has been made in consideration of the above circumstances, and aims to provide a sheet feeding device and an image forming apparatus in which a separating air blowing fan for blowing separating air at sheets loaded in a sheet feeding section moves together with a side regulating section that regulates the position of the sheet in the width direction, and which does not deteriorate operability when moving the side regulating section. [Means for solving the problem]

[0010] In order to achieve the above object, the present invention provides a sheet feeding section capable of feeding a sheet, a side regulating section for regulating a position of the sheet feeding section in a sheet width direction perpendicular to a sheet feeding direction, a separating air outlet provided in the side regulating section for blowing separating air to a sheet placed on the sheet feeding section, a separating air blowing fan movable together with the side regulating section for supplying separating air to the separating air outlet, a side regulating section guide section for guiding the side regulating section so as to be movable in the sheet width direction, and a separating air blowing fan movable together with the side regulating section. The present invention provides a sheet feeding device and an image forming apparatus having a separating air blowing fan guide section that movably guides the separating air blowing fan, a separating air blowing fan side duct that is fixed to the separating air blowing fan side and blows the separating air supplied from the separating air blowing fan to the separating air outlet of the side regulating section, and a side regulating section side duct that is fixed to the side regulating section side and is connected to the separating air blowing fan side duct with a predetermined movable gap therebetween in order to blow the separating air from the separating air blowing fan side duct to the separating air outlet of the side regulating section. Effect of the Invention

[0011] According to the present invention, a sheet feeding device and an image forming apparatus can be provided in which a separating air blowing fan for blowing separating air onto sheets loaded in a sheet feeding section moves together with a side regulating section that regulates the position of the sheet in the width direction, and which does not deteriorate operability when moving the side regulating section. [Brief description of the drawings]

[0012] [Figure 1] 1 is a schematic front cross-sectional view of an image forming apparatus according to an embodiment of the present invention. [Diagram 2] FIG. 1 is a circuit block diagram according to an embodiment of the present invention. [Diagram 3] FIG. 2 is a top view of a manual feed section according to the embodiment of the present invention. [Figure 4] 5A and 5B are top views of the manual feed section showing the open and closed states of the side regulating plate according to the embodiment of the present invention. [Diagram 5] 5 is a cross-sectional view taken along line AA in FIG. 4 according to an embodiment of the present invention. [Figure 6] FIG. 4 is an explanatory diagram illustrating a connection state of an air duct according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. Note that the components described in the following embodiments are merely examples, and various conditions such as the configuration, function, dimensions, materials, shape, and relative arrangement of the device to which the present invention is applied can be appropriately modified or changed without departing from the spirit of the present invention, and are not limited to the following embodiments.

[0014] FIG. 1 is a schematic front sectional view of an image forming apparatus according to an embodiment of the present invention.

[0015] In Fig. 1, 200 denotes an image forming apparatus, which is a tandem type intermediate transfer type laser beam printer that utilizes an electrophotographic process. The image forming apparatus 200 can form and output a full-color or monochrome image corresponding to print image data output from a host device 900 connected to a control unit 100 shown in Fig. 2, which will be described later, on a sheet S, which is a recording medium.

[0016] Reference numeral 201 denotes an image forming apparatus main body, and reference numeral 202 denotes an image reading device installed approximately horizontally above the image forming apparatus main body 201. Between this image reading device 202 and the image forming apparatus main body 201, an ejection space V for ejecting sheets is formed.

[0017] Reference numeral 230 denotes a cassette feeding section serving as a sheet feeding section that feeds sheets S from a feeding cassette 1 that is a sheet storage means for storing sheets S. The cassette feeding section 230 includes a pickup roller 2 that is a sheet feeding means, and a separation section that includes a feed roller 3 and a retard roller 4 for separating the sheets S sent out from the pickup roller 2.

[0018] Also, reference numeral 235 denotes a manual feed unit serving as a sheet feed unit capable of feeding a manually-fed sheet S from a manual feed tray 5 serving as a means for placing a sheet S. Similarly to the cassette feed unit 230, the manual feed unit 235 includes a pickup roller 502 serving as a sheet feeding means, and a separation unit including a feed roller 503 and a retard roller 504 for separating the sheet S fed from the pickup roller 502.

[0019] 201A is an image forming unit which is an image forming means for forming an image on a sheet, and is a four-drum full-color type. The image forming unit 201A is equipped with a laser scanner 210 and four process cartridges 211Y, 211M, 211C, and 211K which form toner images of four colors, yellow (Y), magenta (M), cyan (C), and black (K). Here, each of the process cartridges 211Y, 211M, 211C, and 211K is equipped with a photosensitive drum 212Y, 212M, 212C, and 212K, a charger 213Y, 213M, 213C, and 213K which is a charging means, and a developer 214Y, 214M, 214C, and 214K which is a developing means. The image forming unit 201A also includes a secondary transfer unit 201D and a fixing unit 201E disposed above the process cartridges 211Y, 211M, 211C, and 211K. Reference numeral 215 denotes a toner cartridge for supplying toner to the developing devices 214Y, 214M, 214C, and 214K, respectively.

[0020] A transfer belt 216 wound around a drive roller 216a and a tension roller 216b is disposed above the photosensitive drums 212Y, 212M, 212C, and 212K. Primary transfer rollers 219Y, 219M, 219C, and 219K are disposed inside the transfer belt 216 and contact the transfer belt 216 at positions facing the photosensitive drums 212Y, 212M, 212C, and 212K, respectively, forming a primary transfer section. The transfer belt 216 is rotated in the direction of arrow H by a drive roller 216a driven by a drive section (not shown). A secondary transfer roller 217 that transfers a color image formed on the transfer belt 216 to a sheet S is disposed at a position facing the drive roller 216a, forming a secondary transfer section 201D.

[0021] Furthermore, a fixing section 201E is disposed above the secondary transfer roller 217, and a first discharge roller pair 225a, a second discharge roller pair 225b, and a double-sided reversing section 201F are disposed at the upper left of the fixing section 201E. The double-sided reversing section 201F is provided with a reversible roller pair 222 and a re-conveying path R for conveying the sheet S, on one side of which an image has been formed, again to the image forming section 201A.

[0022] An input display device 730 for receiving operations from a user is provided on the upper portion of the image forming apparatus main body 201. The input display device 730 is of a touch panel type that is capable of not only displaying but also inputting information.

[0023] FIG. 2 is a circuit block diagram for controlling the image forming apparatus of FIG.

[0024] 2, the control unit 100 is a control circuit that controls the overall operation of the image forming apparatus 200, and transmits and receives information to and from the host device 900 and the input display device 730. The control unit 100 also performs signal processing and sequence control for various process devices. Here, the host device 900 is a personal computer, an image scanner, a facsimile machine, or the like.

[0025] The control unit 100 also transmits and receives information to and from a storage unit 101 that is configured from a RAM and a ROM. The storage unit 101 stores various control programs and the like.

[0026] The control unit 100 is also connected to separation air blowing fans 15a and 15b, which will be described later, for separating the sheet stack stacked on the manual feed unit 235 with air, and controls the separation air blowing fans 15a and 15b.

[0027] Furthermore, the control unit 100 is connected to a sheet detection sensor 505 (described later) for detecting a sheet placed on the manual feed unit 235 .

[0028] Next, the image forming operation of the image forming apparatus 200 will be described.

[0029] 1 and 2, first, in the image forming apparatus 200, when the control unit 100 receives image data of an original to be printed from the host device 900, the image information is subjected to image processing and then transmitted to the laser scanner 210 of the image forming unit 201A. In the image forming unit 201A, the surfaces of the photoconductor drums 212Y, 212M, 212C, and 212K, the surfaces of which are uniformly charged to a predetermined polarity and potential by the chargers 213Y, 213M, 213C, and 213K, are sequentially exposed by the laser scanner 210. As a result, electrostatic latent images of yellow, magenta, cyan, and black are sequentially formed on the photoconductor drums Y, 212M, 212C, and 212K of the process cartridges 211Y, 211M, 211C, and 211K, respectively.

[0030] Thereafter, the electrostatic latent images are developed and visualized with toners of the respective colors by the developers 214Y, 214M, 214C, and 214K, and the toner images of the respective colors on the photoconductor drums 212Y, 212M, 212C, and 212K are transferred in sequence onto the transfer belt 216 in a superimposed manner by a primary transfer bias applied to the primary transfer rollers 219Y, 219M, 219C, and 2129. As a result, a toner image is formed on the transfer belt 216.

[0031] In parallel with this toner image forming operation, the sheets S are conveyed one by one by the cassette feeding unit 230 or the manual feeding unit 235 to the pair of registration rollers 240, and skew is corrected by the pair of registration rollers 240. After skew is corrected, the sheets S are conveyed to the secondary transfer unit 201D by the pair of registration rollers 240, and in the secondary transfer unit 201D, the toner images on the transfer belt 216 are transferred all at once onto the sheets S by the secondary transfer bias applied to the secondary transfer roller 217.

[0032] Then, the sheet S onto which the toner image has been transferred is transported to the fixing section 201E, where the toner of each color melts and mixes with heat and pressure in the roller nip portion formed by the pressure roller 220a and the heating roller 220b, and is fixed onto the sheet S as a color image.

[0033] The sheet S with the image fixed thereon is discharged to the discharge space V by a first discharge roller pair 225a and a second discharge roller pair 225b provided downstream of the fixing section 201E, and is loaded onto a discharge tray 223 protruding from the bottom surface of the discharge space V.

[0034] When images are formed on both sides of the sheet S, after the images are fixed in the fixing section 201E, the sheet S is transported to a re-transport path R by a pair of reversing rollers 222 and transported again to the image forming section 201A.

[0035] Next, the manual feed section 235 having the separating air blowing section will be described.

[0036] FIG. 3 is a top view of the manual feed section 235. FIG.

[0037] In FIG. 3, the manual feed section 235 includes a manual feed tray 5 which is a means for placing sheets as described above, a pickup roller 502 which is a sheet feeding means, and a separation section which includes a feed roller 503 for separating the sheet S sent out from the pickup roller 502 and the retard roller 504 shown in FIG. 1.

[0038] The manual feed tray 5 is provided with side regulation portions 14a and 14b as side regulation plates that regulate the position of the sheet in a sheet width direction X perpendicular to an arrow Y indicating the sheet feeding direction relative to the sheet placement surface.

[0039] The side regulating parts 14a, 14b are respectively fitted with separating air blowing fans 15a, 15b so as to be movable together with the side regulating parts 14a, 14b, and are capable of blowing separating air A1, A2, A3, A4 onto the sides of the stacked sheets S via blowing nozzles 16a, 17a, 16b, 17b as separating air outlets. By blowing separating air from the separating air blowing fans 15a, 15b toward the ends of the sheets as in the flow lines A1, A2, A3, A4, the separating air enters the gaps in the sheet stack, causing the upper sheets of the sheet stack to float, thereby reducing the suction force between the sheets.

[0040] When a start button on the input display device 730 is pressed, sheet feeding is started. If the sheet to be fed is a coated paper, the separating air blowing fans 15a, 15b attached to the side regulating units 14a, 14b are operated before the sheet feeding is started to blow separating air to the end of the sheet in the width direction through the blowing nozzles 16a, 17a, 16b, 17b. Then, after a predetermined time, the pickup roller 502 rotates, and the sheet S, which is the top coated paper in a state in which the adhesive force between the coated papers is reduced, is sent to a separation unit consisting of the feed roller 503 and the retard roller 504 shown in FIG. 1, and the leading edge of the separated sheet S is detected by the sheet detection sensor 505 and sent to the above-mentioned registration roller pair 240 by the conveying roller pair 506.

[0041] As described above, the subsequent operation is such that the toner image is transferred to the sheet S at the secondary transfer section 201D at a timed interval. Then, the toner image is fixed to the sheet S at the fixing section 201E, and the sheet S is discharged onto the discharge tray 223 by the first discharge roller pair 225a.

[0042] On the other hand, when forming a double-sided image, the sheet is inverted in the double-sided inversion section 201F and transported again to the pair of registration rollers 240 via the re-transport path R. Thereafter, the toner image is transferred and fixed in the same manner as for the first side, and the sheet is discharged onto the discharge tray 223, completing a series of image formation processes.

[0043] Fig. 4 is a top view of the manual feed unit 235 showing the open and closed states of the side regulating unit, Fig. 4(A) shows the side regulating unit in an open state corresponding to the maximum size width of the sheets to be placed, and Fig. 4(B) shows the side regulating unit in a closed state corresponding to the minimum size width of the sheets to be placed. Fig. 5 is a cross-sectional view taken along the line AA in Fig. 4.

[0044] 4 and 5, side regulating portions 14a and 14b are movably guided and supported in a sheet width direction X perpendicular to the sheet feeding direction Y by a slide shaft (not shown) that serves as a side regulating portion guide portion with respect to manual feeding tray 5, and their positions are regulated in the other directions, that is, the sheet feeding direction Y and the sheet surface direction Z. In addition, by operating side regulating portion 14a that regulates one position in the sheet width direction X by a rack and pinion gear (not shown), side regulating portion 14b that regulates the other position in the sheet width direction X is linked, and the distance between side regulating portions 14a and 14b can be changed.

[0045] The separating air blowing fans 15a, 15b are provided inside the housing of the manual feed tray 5 below the sheet stacking surface 5a, which is the sheet placement position of the manual feed tray 5, and are equipped with a sirocco fan that has a relatively large air volume, is quiet, and has good durability, and are arranged sideways to save space due to the shape of the sirocco fan and the configuration of the separating air outlet. The separating air blowing fans 15a, 15b are held by a fan holding base (not shown), and are movably guided and supported by slide shafts 18a, 18b that extend in the sheet width direction X of the manual feed tray 5 and serve as separating air blowing fan guides different from the slide shafts (not shown) that support the side regulation parts 14a, 14b, and their positions are regulated in the other directions, that is, the sheet feed direction Y and the sheet surface direction Z.

[0046] Air supply ducts 19 are provided between the separation air blowing fans 15a, 15b and the side regulating parts 14a, 14b, respectively, and the separation air blowing fans 15a, 15b and the side regulating parts 14a, 14b are connected via the air supply ducts 19, respectively, to form air passages for guiding and sending the separation air blown from the separation air blowing fans 15a, 15b to the side regulating parts 14a, 14b.

[0047] The air duct 19 is made up of a separation air fan side duct 20 fixed to the separation air fans 15a, 15b side, and a side regulation portion side duct 21 fixed to the side regulation portions 14a, 14b side.

[0048] FIG. 6 is an explanatory diagram for explaining a connection state between the separation air blowing fan side duct 20 and the side regulating portion side duct 21. As shown in FIG.

[0049] 6, the separation air blowing fan side duct 20 and the side regulating section side duct 21 are shaped so that the side regulating section side duct 21 covers the separation air blowing fan side duct 20. As shown in Fig. 6(A), which is a cross-sectional view in the sheet feeding direction Y, the outside of the separation air blowing fan side duct 20 and the inside of the side regulating section side duct 21 are relatively movable with respect to the sheet feeding direction Y and the sheet surface direction Z with a predetermined gap that is equal to or larger than the deviation between the movement positions of the side regulating sections 14a, 14b guided by slide shafts (not shown) serving as side regulating section guide sections and the movement positions of the separation air blowing fans 15a, 15b guided by slide shafts 18a, 18b serving as separation air blowing fan guide sections. On the other hand, as shown in FIG. 6B, which is a cross-sectional view taken along the line BB in FIG. 6A, the movement position in the sheet width direction X is restricted by the outside of the separating air blowing fan side duct 20 and the inside of the side restricting portion side duct 21.

[0050] With the above configuration, when side regulating portion 14a is operated to move it, force is transmitted to side regulating portion side duct 21 fixed to side regulating portions 14a, 14b, and force is transmitted from side regulating portion side duct 21 which regulates the movement position in the sheet width direction X to separation air blowing fan side duct 20, and then the force is transmitted to separation air blowing fans 15a, 15b to which separation air blowing fan side duct 20 is fixed, and the separation air blowing fans 15a, 15b move together with side regulating portions 14a, 14b.

[0051] Here, the positions of the slide shaft (not shown) that guides and supports the side regulating parts 14a, 14b and the slide shafts 18a, 18b that guide and support the separation air blowing fans 15a, 15b are each fixed with respect to the manual feed tray 5, so there is a possibility that the movement position of the side regulating part side duct 21 that connects the side regulating parts 14a, 14b and the separation air blowing fans 15a, 15b will differ from the movement position of the separation air blowing fan side duct 20.

[0052] However, although the movement positions in the sheet width direction X of the side regulating portion-side duct 21 fixed to the side regulating portions 14a, 14b and the air blowing fan-side duct 20 fixed to the separating air blowing fans 15a, 15b are restricted, a predetermined gap is provided in the other directions, that is, the sheet feed direction Y and the sheet surface direction Z, as described above, so that even if the connection positions of the side regulating portions 14a, 14b and the separating air blowing fans 15a, 15b are misaligned, the separating air blowing fan-side ducts 20, 21 can be connected without being deformed, such as twisted or bent, due to the ducts being misaligned with each other.

[0053] That is, as shown in Fig. 6(C), which is a cross-sectional view in the sheet feeding direction Y, even if the positions of the separation air blowing fans 15a, 15b are shifted in the direction of the arrow M relative to the positions of the side regulating parts 14a, 14b, the separation air blowing fan side duct 20 has a predetermined gap greater than the amount of the shift in the sheet feeding direction Y and the sheet surface direction Z, so that the separation air blowing fans can be connected without deformation such as twisting or bending, and thus deterioration of operability when moving the side regulating parts can be prevented. Also, since the opening of the side regulating part side duct 21 is wider than the opening of the separation air blowing fan side duct 20 moved in the direction of the arrow M, separation air can be sent from the separation air blowing fan side duct 20 to the side regulating part side duct 21 without being affected by the positional shift.

[0054] As explained in Fig. 3, when coated paper or the like is set in the manual feed section 235 and the paper feed operation is started, the separating air blowing fans 15a, 15b rotate to take in outside air from an air intake (not shown) provided in the exterior section 5b of the manual feed tray 5 shown in Fig. 5 as shown by flow line E1, and send the separating air to the separating air blowing fan side duct 20 fixed to the air outlet on the separating air blowing fans 15a, 15b side. The separating air sent to the separating air blowing fan side duct 20 proceeds to the side regulating section side duct 21 fixed to the side regulating sections 14a, 14b side as shown by flow lines D1, D2, and sends the separating air from the side regulating section side duct 21 to the separating air blowing ducts 22a, 22b formed inside the side regulating sections 14a, 14b as shown by flow lines C1, C2. Furthermore, two blowing nozzles 16a and 17a, as well as two blowing nozzles 16b and 17b are arranged on the sheet regulating surfaces of the side regulating sections 14a and 14b, respectively, and the separating air advances inside the separating air blowing ducts 22a and 22b as shown by the flow lines B1 and B2, and is blown from the blowing nozzles 16a and 17a, as well as the blowing nozzles 16b and 17b, as shown by the flow lines A1 and A2, as well as the blowing nozzles A3 and A4 onto the ends of the placed sheet S. [Explanation of symbols]

[0055] 5. Manual feed tray 14a, 14b...Side regulation parts 15a, 15b...Air blowing fan 16a, 16b, 17a, 17b...Spray nozzle 18a, 18b...Slide shaft 19, 20, 21...Ventilation duct 100...Control unit 200...Image forming apparatus 235...Manual feed section S…Seat

Claims

1. a sheet feeding section capable of feeding a sheet; a side regulating portion for regulating a position of the sheet feeding portion in a sheet width direction perpendicular to a sheet feeding direction; a separating air outlet provided in the side regulating section for blowing separating air onto the sheets placed on the sheet feeding section; a separation air blowing fan movable together with the side regulating portion for supplying separation air to the separation air outlet; a side regulating portion guide portion that guides the side regulating portion so as to be movable in a seat width direction; a separation air blowing fan guide portion that movably guides the separation air blowing fan together with the side regulating portion; a separation air blowing fan side duct that is fixed to the separation air blowing fan side and blows the separation air supplied from the separation air blowing fan to the separation air outlet of the side regulating portion; a side regulating section side duct that is fixed to the side regulating section side and is connected to the separation air blowing fan side duct with a predetermined movable gap therebetween in order to blow the separation air from the separation air blowing fan side duct to the separation air outlet of the side regulating section; A sheet feeding device comprising:

2. 2. The sheet feeding device according to claim 1, wherein the specified movable gap is greater than or equal to the deviation between the movement position of the side regulating portion guided by the side regulating portion guide portion and the movement position of the separation air blowing fan guided by the separation air blowing fan guide portion.

3. 2. The sheet feeding device according to claim 1, wherein the moving positions of the separating air blowing fan side duct and the side regulating portion side duct in the sheet width direction are regulated.

4. 2. The sheet feeding device according to claim 1, wherein the opening of the duct on the side regulating portion covers the duct on the side of the separating air blowing fan with the predetermined movable gap.

5. 2. The sheet feeding apparatus according to claim 1, wherein the sheet feeding section is a manual feeding section.

6. an image forming unit that forms an image on a sheet; The sheet feeding device according to claim 1 , which is capable of feeding a sheet to the image forming unit; An image forming apparatus comprising:

Images