Image forming apparatus

Abstract

To miniaturize the height of a device main body.SOLUTION: The image forming apparatus includes a first cover part 66 and a second cover part 34 which are arranged above a loading tray 31 and below an intermediate transfer belt 61, and overlap a loading surface 31a and the intermediate transfer belt 61 when viewed in a gravity direction. In a case where the stack tray 31 moves from the drawn-out position to the mounted position in the extended state, the second cover part 34 moves to the D1 in the mounting direction in accordance with the movement of the stack tray 31. When the stack tray 31 is located at the attachment position in the expanded state, the protruding portion side 34e of the stack tray 31 is located downstream of the housing side 1a in the attachment direction, and the second cover portion 34 covers the protruding portion side D1 from above, and when the stack tray 31 is located at the attachment position, at least a part of the second cover portion 34 is located downstream of the first cover downstream end side 34e in the attachment direction D1, and has a region 66B that overlaps the intermediate transfer belt 61 and the stacking surface 31a when viewed in the gravity direction. Ar1.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to an image forming apparatus that forms an image on a recording material. [Background technology]

[0002] In electrophotographic image forming apparatuses, an intermediate transfer method is widely used in which a toner image is primarily transferred from a photosensitive drum to an intermediate transfer belt, the primarily transferred toner image is then transported to a secondary transfer section by the intermediate transfer belt, and the toner image is then transferred to a recording material at the secondary transfer section. In such image forming apparatuses, a stacking tray for storing recording materials may be disposed below the intermediate transfer belt. In such cases, a known configuration is to provide a plate-shaped protective member between the intermediate transfer belt and the stacking tray to protect the recording materials stored in the stacking tray from toner, dust, and the like that may fall from the intermediate transfer belt (see Patent Document 1). In this image forming apparatus, the protective member is disposed above the entire area of ​​the stacking tray except for the feeding section.

[0003] Meanwhile, a stacking tray capable of accommodating not only standard-sized sheets but also long sheets as recording materials is known (see Patent Document 2). This stacking tray is shortened when accommodating standard-sized sheets to reduce the size of the device, and is extendable when accommodating long sheets. In an image forming device using this stacking tray, when a stacking tray containing long sheets is installed in the image forming device, the stacking tray and a portion of the recording material protrude outside the device body. For this reason, a dust cover is provided on the device body to protect the protruding recording material from dust and dirt. This dust cover is configured to move in the installation direction of the stacking tray in conjunction with the position of the leading edge of the stacking tray in the installation direction. When the stacking tray protrudes outside the device body, the protective cover also moves outside the device body in conjunction with the position of the leading edge of the stacking tray in the installation direction to protect the sheet. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-038492 [Patent Document 2] Japanese Patent Application Laid-Open No. 2012-058295 Summary of the Invention [Problem to be solved by the invention]

[0005] However, when the dustproof cover described in Patent Document 2 is provided on an image forming apparatus having the protective member described in Patent Document 1, the protective member and the dustproof cover are arranged overlapping each other in the direction of gravity, which increases the height in the direction of gravity and may lead to an increase in the size of the apparatus body.

[0006] SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming apparatus that can be made smaller in size in terms of the height of the apparatus body. [Means for solving the problem]

[0007] According to one aspect of the present invention, there is provided a sheet transport device including: a housing; a photosensitive member on which a toner image is formed; and a storage unit having a loading surface for loading sheets and configured to store the sheets, the storage unit being configured to take a pulled-out position when pulled out from the housing and a loaded position when moved in a loading direction from the pulled-out position to a loaded position when loaded into the housing; a feeding unit that feeds the sheets stored in the storage unit; a transfer belt disposed above the storage unit, the transfer belt having the toner image transferred from the photosensitive member and transferring the toner image to a sheet fed by the feeding unit; a first cover portion disposed above the storage unit and below the transfer belt, the first cover portion overlapping the loading surface and the transfer belt as viewed in the direction of gravity; and a second cover portion disposed above the storage unit and below the transfer belt, the second cover portion overlapping the loading surface and the transfer belt as viewed in the direction of gravity. The storage unit has a main body portion and an expansion portion that is provided so as to be movable in the loading direction relative to the main body portion. and a second state in which the extension portion is moved in the installation direction relative to the main body portion so that the length of the storage portion in the installation direction becomes a second length that is longer than the first length. When the storage portion moves from the pulled-out position to the installation position in the second state, the second cover portion moves in the installation direction in conjunction with the movement of the storage portion, and the downstream end of the housing in the installation direction is the downstream end of the housing. When the storage portion is located at the installation position in the second state, a portion of the storage portion is downstream of the downstream end of the housing in the installation direction, and the second cover portion covers the portion of the storage portion from above, and the downstream end of the first cover portion in the installation direction is the downstream end of the first cover. When the storage portion is located at the installation position, at least a portion of the second cover portion is downstream of the downstream end of the first cover in the installation direction, and has a portion that overlaps the transfer belt and the loading surface as viewed in the direction of gravity. [Effects of the Invention]

[0008] According to the present invention, it is possible to reduce the height of the device body. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a cross-sectional view showing an image forming apparatus according to a first embodiment. [Figure 2] 1A and 1B are perspective views showing a stacking tray according to a first embodiment, in which FIG. 1A is in a normal state and FIG. 1B is in an extended state. [Figure 3] 1A and 1B are diagrams showing a state in which a stacking tray in a normal state is attached to an apparatus main body according to a first embodiment, in which (a) is a side view and (b) is a cross-sectional view. [Figure 4] 1A and 1B are diagrams showing a state in which an extended stacking tray is being mounted on an apparatus main body according to a first embodiment, where FIG. 1A is a side view and FIG. 1B is a cross-sectional view. [Figure 5] 1A and 1B are diagrams showing a state in which an extended stacking tray is attached to an apparatus main body according to a first embodiment, in which (a) is a side view and (b) is a cross-sectional view. [Figure 6] This is a schematic diagram viewed from above showing the relationship between the first cover part, the second cover part, the secondary transfer belt, and the loading surface in the first embodiment, where (a) is the normal state of the loading tray and (b) is the extended state of the loading tray. [Figure 7] 10A and 10B are perspective views showing a stacking tray according to a second embodiment, in which FIG. 10A is in a normal state and FIG. [Figure 8] FIG. 10 is a cross-sectional view showing a state in which a stacking tray in a normal state is attached to an apparatus main body according to a second embodiment. [Figure 9] 10A and 10B are cross-sectional views showing a state in which an extended stacking tray is being attached to an apparatus main body according to a second embodiment, in which FIG. 10A shows a state in the middle of being attached, and FIG. [Figure 10] 10A and 10B are perspective views showing a stacking tray according to a third embodiment, in which FIG. 10A is in a normal state and FIG. [Figure 11] FIG. 11 is a cross-sectional view showing a state in which a stacking tray in a normal state is attached to an apparatus main body according to a third embodiment. [Figure 12]10A and 10B are cross-sectional views showing a state in which an extended stacking tray is being attached to an apparatus main body according to a third embodiment, in which FIG. 10A shows a state in the middle of being attached, and FIG. DETAILED DESCRIPTION OF THE INVENTION

[0010] First Embodiment A first embodiment of the present invention will be described in detail below with reference to Figures 1 to 6(b). First, the schematic configuration of an image forming apparatus 1 according to this embodiment will be described with reference to Figure 1. Unless otherwise specified, the dimensions, materials, relative positions, etc. of the components of the image forming apparatus 1 are not intended to limit the scope of the present invention to those alone.

[0011] [Image forming device] FIG. 1 is a schematic diagram of an image forming apparatus 1 according to this embodiment. In this embodiment, the image forming apparatus 1 is an electrophotographic color laser beam printer that forms an image on a sheet S as a recording material. The image forming apparatus 1 has a housing 1a and a door 1b that can be opened and closed at the front of the housing 1a. The image forming apparatus 1 also houses an image forming unit 2, a sheet feeding unit 3, a sheet conveying unit 4, a fixing device 5, a control unit 6, and other components housed within the housing 1a. In this embodiment, the direction in which a stacking tray 31 is attached to and detached from the image forming apparatus 1 is defined as the front-to-rear direction, and the direction of gravity is defined as the up-to-down direction. In each drawing, the front side in the front-to-rear direction is defined as the front direction F, and the rear side is defined as the rear direction B. In the up-to-down direction, the upper side is defined as the up direction U, and the lower side is defined as the down direction D. The right side as viewed from the front side is defined as the right direction R, and the left side is defined as the left direction L (see FIG. 2(a), etc.). The housing 1a has a front cover 11F, a rear cover 11B, a right side wall 11R, and a left side wall 11L (see FIGS. 3(a) and 6(a)).

[0012] The sheet feeding section 3 has a stacking tray 31 on which sheets S as recording materials are stacked, and a feeding roller 32. The feeding roller 32 is an example of a feeding section, and feeds the sheets S stored in the stacking tray 31. In this embodiment, the pull-out direction D2 is a direction along the feeding direction in which the feeding roller 32 feeds the sheets S. In other words, the mounting direction D1 is the opposite direction to the pull-out direction D2, and is a direction along the feeding direction from downstream to upstream.

[0013] The stacking tray 31 is configured to be insertable into the housing 1a of the image forming apparatus 1 in an insertion direction D1 and removable by withdrawing in a withdrawal direction D2. Here, the insertion direction D1 and the withdrawal direction D2 are horizontal. That is, the stacking tray 31 is an example of a storage section and has a stacking surface 31a for stacking sheets and stores sheets S. The stacking tray 31 has a lifting plate 31b on the downstream side of its bottom in the withdrawal direction D2, and the top sheet S of the stored sheet stack rises so as to be fed by the feed roller 32. The stacking surface 31a is a surface within the stacking tray 31 that includes at least an area where sheets S of the maximum size on which images can be formed by the image forming apparatus 1 are stacked, including both areas with and without the lifting plate 31b. That is, because it is preferable to prevent toner from falling in an area wider than the area where the maximum-size sheets S are stacked, such an area is designated as the stacking surface 31a.

[0014] The stacking tray 31 can be attached to the housing 1a in an attachment direction D1 and can be removed from the housing 1a in a removal direction D2, which is the opposite direction to the attachment direction D1. Thus, the stacking tray 31 can be moved from the attachment position to a removal position in the housing 1a by moving in the attachment direction D1 from the removal position. In this embodiment, the attachment direction D1 is the rear direction B, and the removal direction D2 is the front direction F, but the attachment direction D1 and the removal direction D2 are not limited to the front-to-rear directions. A second cover 34, which is a dustproof cover, is provided above the attachment direction D1 of the stacking tray 31 to protect the sheets S stored in the stacking tray 31 from dust and dirt. The second cover 34 will be described later.

[0015] The image forming unit 2 includes process cartridges PY, PM, PC, and PK, an exposure device 20, a transfer unit 60, and the like. The process cartridges PY, PM, PC, and PK are independently detachably supported on a tray 21 and contain yellow (Y), magenta (M), cyan (C), and black (K) toner (developers), respectively. The process cartridges PY, PM, PC, and PK have the same configuration except for the toner colors they contain, so the yellow process cartridge PY will be described here. The process cartridge PY includes a photosensitive drum 22 corresponding to yellow toner, a charging roller 23, and a developing roller 24. The photosensitive drum 22 is an example of a photosensitive body, and a toner image corresponding to each toner color is formed and carried on the photosensitive drum 22. The photosensitive drum 22 has a rotation axis extending in the left-right direction D3 (see FIG. 2(a)), i.e., the sheet width direction perpendicular to the conveying direction of the conveyed sheet S.

[0016] The transfer unit 60 includes an intermediate transfer belt 61, a primary transfer roller 62, a cleaning unit 63, a drive roller 64 that drives the intermediate transfer belt 61, and a tension roller 65 that applies tension to the intermediate transfer belt 61. That is, the intermediate transfer belt 61 is stretched by the drive roller 64, which is an example of a first roller, and the tension roller 65, which is an example of a second roller, and is disposed downstream of the drive roller 64 in the installation direction D1. The intermediate transfer belt 61 is an example of a transfer belt and is disposed inside the housing 1a and above the stacking tray 31 in the vertical direction. The intermediate transfer belt 61 receives a toner image transferred from the photosensitive drum 22 and transfers the transferred toner image onto the sheet S fed by the feed roller 32. In this embodiment, the photosensitive drum 22 is disposed above the intermediate transfer belt 61 in the vertical direction. The intermediate transfer belt 61 abuts against the photosensitive drum 22 and forms a primary transfer unit 51 that primarily transfers the toner image carried on the photosensitive drum 22 to the intermediate transfer belt 61.

[0017] A first cover portion 66 is disposed below the intermediate transfer belt 61 as a protective member that prevents toner that has fallen from the intermediate transfer belt 61 from reaching the stacking tray 31. This prevents the sheets S stored in the stacking tray 31 from being contaminated by toner remaining on the intermediate transfer belt 61 falling. That is, the first cover portion 66 is provided on the housing 1a and is disposed between the stacking tray 31 and the intermediate transfer belt 61 in the vertical direction, covering the top of the stacking tray 31. In this embodiment, the first cover portion 66 is formed of, for example, a flat plate-shaped member.

[0018] As shown in FIG. 6(a), the housing 1a has a right side wall 11R and a left side wall 11L on both sides of the left-right direction D3, which is the direction of the rotation axis of the photosensitive drum 22. Note that FIGS. 6(a) and 6(b) are schematic diagrams, and the aspect ratios of the components are different from the actual figures. The first cover portion 66 is supported on both sides of the rotation axis direction by the right side wall 11R and the left side wall 11L of the housing 1a. Note that support by the right side wall 11R and the left side wall 11L here is not limited to direct support of the first cover portion 66 by the right side wall 11R and the left side wall 11L. It also includes indirect support, such as when the first cover portion 66 is supported by a frame that supports the right side wall 11R and the left side wall 11L, or when the first cover portion 66 is supported via a separate member attached to the right side wall 11R and the left side wall 11L. The first cover portion 66 is disposed above the stacking tray 31 and below the intermediate transfer belt 61, and overlaps the stacking surface 31a and the intermediate transfer belt 61 when viewed in the direction of gravity.

[0019] 1, the sheet conveying unit 4 has a registration roller pair 40 that conveys the sheet S fed from the feed roller 32, and a secondary transfer roller 41 that is arranged downstream of the registration roller pair 40 in the sheet conveying direction. The intermediate transfer belt 61 and the secondary transfer roller 41 form a secondary transfer unit 52 that transfers the toner image that has been primarily transferred onto the intermediate transfer belt 61 onto the sheet fed by the feed roller 32. The registration roller pair 40 corrects skew of the sheet S and adjusts the timing of conveying the sheet S to the secondary transfer unit 52 to match the timing of the toner image carried on the intermediate transfer belt 61. The fixing device 5 has a fixing roller pair 50 that has a heating roller and a pressure roller.

[0020] [Image formation operation] 1, the image forming operation of the image forming apparatus 1 will be described. The control unit 6 of the image forming apparatus 1 starts the image forming operation on the sheet S based on an image signal received from an external host device 100. The external host device 100 is, for example, a personal computer, an image reader, a facsimile machine, etc.

[0021] When an image formation job is started by the control unit 6, a charging voltage is applied to the charging roller 23, and the photosensitive drum 22 rotates and is charged by the charging roller 23. A laser beam corresponding to image information is irradiated from the exposure device 20 onto the photosensitive drum 22, exposing the charged surface of the photosensitive drum 22. As a result, an electrostatic latent image corresponding to the image information is formed on the surface of the photosensitive drum 22. Immediately thereafter, a developing voltage is applied to the developing roller 24, and the electrostatic latent image formed on the photosensitive drum 22 is developed with toner supplied from the developing roller 24, thereby forming a toner image on the surface of the photosensitive drum 22. The toner image formed on the photosensitive drum 22 of each process cartridge PY, PM, PC, and PK is transferred onto the intermediate transfer belt 61 by the primary transfer roller 62 and transported toward the secondary transfer unit 52 formed by the intermediate transfer belt 61 and the secondary transfer roller 41.

[0022] Meanwhile, a conveying path 42 is formed in the housing 1a of the image forming apparatus 1, through which the sheets S heading toward the fixing device 5 pass. In addition, a double-sided conveying path 43 is formed in the door 1b, through which the sheets S pass after passing through the fixing device 5. In the sheet feeding unit 3, one sheet S is separated and fed from the sheets S stacked on the stacking tray 31 by the feeding roller 32 at a predetermined timing, and is conveyed through the conveying path 42 toward the secondary transfer unit 52 and the fixing device 5.

[0023] In the secondary transfer unit 52, the toner image is transferred from the intermediate transfer belt 61 to the sheet S. Toner that has not been transferred to the sheet S is removed from the intermediate transfer belt 61 by a cleaning blade 63a provided in the cleaning unit 63. The sheet S, onto which the toner image has been transferred in the secondary transfer unit 52, is transported toward the fixing device 5. In the fixing device 5, the sheet S is heated and pressed by a pair of fixing rollers 50, and the toner image is fixed to the sheet S. The sheet S, onto which the toner image has been fixed, is transported toward the discharge / reversal unit 44.

[0024] The discharge / reversal unit 44 is movable between a discharge position where it guides the sheet S that has passed through the fixing device 5 toward a discharge path 45 and a reverse position where it guides the sheet S toward a reverse path 46. When single-sided printing is performed, in which an image is formed on one side of the sheet S, the sheet S is guided to the discharge path 45 by the discharge / reversal unit 44 and discharged to a discharge tray 47 formed at the top of the image forming apparatus 1. On the other hand, when double-sided printing is performed, in which images are printed on both sides of the sheet S, the sheet S is guided to the reverse path 46 by the discharge / reversal unit 44. When the sheet S is guided to the reverse path 46, the conveyance direction of the sheet S is reversed, and the sheet S is conveyed again toward the secondary transfer unit 52 through a double-sided conveyance path 43 formed in the door 1b. After a toner image is transferred to the back side of the sheet S in the secondary transfer unit 52, the sheet S passes through the fixing device 5, is guided to the discharge path 45 by the discharge / reversal unit 44, and is discharged to the discharge tray 47 of the image forming apparatus 1.

[0025] [Configuration of the loading tray and second cover] Next, the configuration of the stacking tray 31 will be described in detail using FIGS. 2(a) and 2(b). The stacking tray 31 includes a tray main body 35, which is an example of a main body, and an extension section 36 that is movable relative to the tray main body 35 in the mounting direction D1 and the withdrawal direction D2. FIG. 2(a) shows a normal state in which the extension section 36 is positioned in the withdrawal direction D2 and the stacking tray 31 is contracted, while FIG. 2(b) shows an expanded state in which the extension section 36 is positioned in the mounting direction D1 and the stacking tray 31 is expanded. That is, the stacking tray 31 can be shifted between a normal state and an expanded state. The normal state is an example of a first state, in which the length (total length) of the stacking tray 31 in the mounting direction D1 is a first length L1. The expanded state is an example of a second state, in which the extension section 36 is moved in the mounting direction D1 relative to the tray main body 35 and the length (total length) of the stacking tray 31 in the mounting direction D1 is a second length L2 that is longer than the first length L1. The stacking tray 31 in the normal state can accommodate standard size sheets such as A4 size, and the stacking tray 31 in the extended state can accommodate long sheets. As a result, when the user loads long sheets onto the stacking tray 31, the user can load them by extending the extension section 36 to expand the storage area for the sheets S.

[0026] Next, the configuration and operation of the second cover unit 34, which is a feature of this embodiment, will be described in detail with reference to FIGS. 3(a) to 6(b). The second cover unit 34 is movable in the front-rear direction relative to the housing 1a and includes a top panel 34a and a rear panel 34b. The top panel 34a has a generally flat plate shape extending horizontally to cover the top of the stacking tray 31 and protect the sheets S stored in the stacking tray 31 from dust and dirt. The top panel 34a includes a cover surface 34c that, together with the first cover unit 66, covers the top of the stacking tray 31 in the up-down direction. In this embodiment, the underside of the top panel 34a forms the cover surface 34c, which covers the top of the stacking tray 31 (see FIGS. 3(b), 4(b), and 5(b)). The second cover unit 34 is disposed above the stacking tray 31 and below the intermediate transfer belt 61, and overlaps the stacking surface 31a and the intermediate transfer belt 61 when viewed in the direction of gravity.

[0027] The rear plate portion 34b has a generally flat plate shape extending downward from the end of the top plate portion 34a on the rear direction B side, and is disposed further rearward in the direction B than the stacking tray 31. That is, the rear plate portion 34b is an example of a side plate portion, and extends vertically at a downstream portion of the second cover portion 34 in the mounting direction D1. Meanwhile, the rear cover 11B has, on its outer surface, a downstream end surface 11a of the housing 1a in the mounting direction D1. The downstream end surface 11a is an example of a downstream end of the housing, which is the downstream end of the housing 1a in the mounting direction D1. When the rear plate portion 34b is located on the same plane as the downstream end surface 11a of the housing 1a, it can form part of the exterior of the image forming apparatus 1. That is, the rear plate portion 34b forms part of the downstream end of the image forming apparatus 1 in the mounting direction D1.

[0028] 3(a) and 3(b) illustrate a state in which the stacking tray 31 is inserted and attached to the image forming apparatus 1 in a normal state in which the extension portion 36 of the stacking tray 31 is not extended. FIGS. 3(a) and 3(b) are a side view and a cross-sectional view, respectively. The second cover portion 34 is supported by a rail member (not shown) inside the image forming apparatus 1 so as to be movable in the attachment direction D1 and the removal direction D2 of the stacking tray 31. The second cover portion 34 is connected to the housing 1a of the image forming apparatus 1 via an elastic member 38 made of a tension coil spring. The elastic member 38 is an example of a biasing portion and biases the second cover portion 34 toward the first position. Note that, although a tension coil spring is used as the elastic member 38 in this embodiment, the present invention is not limited thereto. For example, a compression coil spring, a leaf spring, a torsion coil spring, or the like may also be used.

[0029] The second cover portion 34 is biased by the elastic member 38 in the pull-out direction D2 of the stacking tray 31, and when the entire second cover portion 34 is housed in the housing 1a, it abuts against an abutment portion 37 provided on the housing 1a and is positioned at a first position where it waits inside the housing 1a. At this time, the rear plate portion 34b of the second cover portion 34 forms the exterior of the image forming apparatus 1. Even when the stacking tray 31 is pulled out from the image forming apparatus 1, the second cover portion 34 is maintained at the first position.

[0030] Below the intermediate transfer belt 61, the first cover portion 66 and the second cover portion 34 are disposed to protect the sheets S stored in the stacking tray 31. Here, the downstream end of the first cover portion 66 in the mounting direction D1 is referred to as the first cover downstream end 66B. When the stacking tray 31 is in the mounting position, at least a portion of the second cover portion 34 is downstream of the first cover downstream end 66B in the mounting direction D1 and has a portion that overlaps the intermediate transfer belt 61 and the stacking surface 31a as viewed in the direction of gravity. This portion is referred to as an area Ar1. At this time, the upstream end 34F (see FIG. 6A) of the second cover portion 34 in the mounting direction D1 is upstream of the first cover downstream end 66B. That is, when the second cover portion 34 is positioned in the first position, the top plate portion 34a of the second cover portion 34 has an area Ar1 that is positioned below the intermediate transfer belt 61 in the vertical direction and does not overlap with the first cover portion 66 as viewed in the vertical direction. This area Ar1 is not limited to the area directly below the intermediate transfer belt 61, but includes an area that is not directly below the intermediate transfer belt 61 but does not overlap with the first cover portion 66 and is located below the intermediate transfer belt 61.

[0031] Furthermore, when the second cover portion 34 is located at the first position, the top panel portion 34a has an area Ar2 that is located below the intermediate transfer belt 61 in the vertical direction and overlaps with the first cover portion 66 when viewed in the vertical direction. That is, the first cover downstream end 66B, which is the downstream end of the first cover portion 66 in the mounting direction D1, overlaps with the second cover portion 34 when viewed in the direction of gravity. Also, there is an area Ar0 where the second cover portion 34 and the first cover portion 66 do not overlap when viewed in the vertical direction, and the first cover portion 66 is not present between the intermediate transfer belt 61 and the stacking tray 31 and the sheets S, and only the second cover portion 34 is present.

[0032] 6A, when the stacking tray 31 is in the mounting position, the upstream end 66F of the first cover portion 66 in the mounting direction D1 is upstream of the upstream end 31aF of the stacking surface 31a. At the same time, the downstream end 34B of the second cover portion 34 in the mounting direction D1 is downstream of the downstream end 31aB of the stacking surface 31a. In addition, in the left-right direction D3, the length of the first cover portion 66 is longer than the length of the stacking surface 31a, and the length of the second cover portion 34 is longer than the length of the stacking surface 31a. As a result, when viewed in the up-down direction, the entire stacking surface 31a is covered by the first cover portion 66 and the second cover portion 34, effectively preventing toner that has fallen from the intermediate transfer belt 61 from reaching the stacking tray 31.

[0033] In this embodiment, the first cover portion 66 is disposed so as to overlap the drive roller 64 but not the tension roller 65 when viewed in the vertical direction. On the other hand, the second cover portion 34 is disposed so as not to overlap the drive roller 64 but to overlap the tension roller 65 when viewed in the vertical direction.

[0034] The rear plate portion 34b has a cover end surface 34d located at the downstream end in the mounting direction D1. When the second cover portion 34 is located in the first position, the cover end surface 34d is flush with the downstream end surface 11a of the housing 1a. Note that "flush" here means that the cover end surface 34d is essentially flush, and is considered to be flush even if it is misaligned in the mounting direction D1 by, for example, about 1 cm.

[0035] Next, referring to FIGS. 4(a) and 4(b), a description will be given of the case where the stacking tray 31 is inserted into the image forming apparatus 1 with the extension portion 36 in the expanded state. FIGS. 4(a) and 4(b) show a side view and a cross-sectional view, respectively, of the stacking tray 31 inserted into the image forming apparatus 1. At this time, the leading end of the extension portion 36 in the installation direction D1 abuts against the rear plate portion 34b of the second cover portion 34 from the front side F, causing the second cover portion 34 to move in the installation direction D1. That is, when the stacking tray 31 moves from the extended position to the installed position in the extended state, the second cover portion 34 moves in the installation direction D1 in conjunction with the movement of the stacking tray 31. The second cover portion 34 is biased in the extraction direction D2 by the elastic member 38. However, the biasing force of the elastic member 38 is sufficient to move the second cover portion 34, which is not subject to external force, to a position where it abuts against the abutment portion 37. The biasing force is a small force slightly greater than the frictional force between the second cover portion 34 and the rail member. Therefore, the biasing force of the elastic member 38 does not hinder the insertion operation of the stacking tray 31, and the stacking tray 31 will not move in the pull-out direction D2 even if the user releases his / her hand during the operation.

[0036] 5(a) and 5(b) show a side view and a cross-sectional view, respectively, of the state in which the extension portion 36 of the stacking tray 31 is in an extended state, the installation into the image forming apparatus 1 is complete, and the second cover portion 34 is in the second position. At this time, the extension portion 36 and the second cover portion 34 are in a state in which they partially protrude from the rear cover 11B at the rear of the housing 1a in the installation direction D1, and the second cover portion 34 protects the sheet S protruding outside the housing 1a from dust and dirt. In other words, the second position is located downstream of the first position in the installation direction D1, and is a position in which at least a portion of the extension portion 36 protrudes downstream from the outer surface (downstream end surface 11a) of the rear cover 11B, which is the downstream end of the housing 1a in the installation direction D1.

[0037] The second cover portion 34 is movable between a first position shown in FIGS. 3A and 3B and a second position shown in FIGS. 5A and 5B. When the expanded stack tray 31 is attached to the housing 1a and the second cover portion 34 is positioned at the second position, the second cover portion 34 covers the upper portion of the portion of the stack tray 31 that protrudes downstream of the rear cover 11B of the housing 1a in the attachment direction D1. That is, when the stack tray 31 is positioned at the attachment position in the expanded state, the protruding portion 34e, which is part of the stack tray 31, is downstream of the downstream end surface 11a of the housing 1a in the attachment direction D1, and the second cover portion 34 covers the protruding portion 34e of the stack tray 31 from above. The second cover portion 34 is biased by the elastic member 38 in the removal direction D2 but stops when it abuts against the stack tray 31. As described above, this biasing force is very small, so that the loading tray 31 will not move in the pull-out direction D2 from the state where it has been completely inserted.

[0038] At this time, the first cover portion 66 and the second cover portion 34 are disposed below the intermediate transfer belt 61 so as to protect the sheets S stored in the stacking tray 31. When the stacking tray 31 is in the mounting position, at least a portion of the second cover portion 34 is downstream of the first cover downstream end 66B in the mounting direction D1 and has a portion that overlaps with the intermediate transfer belt 61 and the stacking surface 31a as viewed in the direction of gravity. This portion is designated as region Ar1, as in the case of FIG. 3(a). At this time, the upstream end 34F (see FIG. 6(b)) of the second cover portion 34 in the mounting direction D1 is upstream of the first cover downstream end 66B. That is, when the second cover portion 34 is in the second position, the top plate portion 34a of the second cover portion 34 has region Ar1 that is positioned below the intermediate transfer belt 61 in the vertical direction and does not overlap with the first cover portion 66 as viewed in the vertical direction.

[0039] Furthermore, the top panel 34a has an area Ar2 that is positioned below the intermediate transfer belt 61 in the vertical direction and overlaps with the first cover portion 66 when viewed in the vertical direction when the second cover portion 34 is located at the second position. That is, even when the second cover portion 34 is located at the second position, the first cover downstream end 66B, which is the downstream end of the first cover portion 66 in the mounting direction D1, overlaps with the second cover portion 34 when viewed in the direction of gravity. Also, there is an area Ar0 where the second cover portion 34 and the first cover portion 66 do not overlap with each other when viewed in the vertical direction, and the first cover portion 66 is not present between the intermediate transfer belt 61 and the stacking tray 31 and the sheets S, and only the second cover portion 34 is present.

[0040] 6(b), when the stacking tray 31 is in the mounted position, the upstream end 66F of the first cover portion 66 in the mounting direction D1 is upstream of the upstream end 31aF of the stacking surface 31a. At the same time, the downstream end 34B of the second cover portion 34 in the mounting direction D1 is downstream of the downstream end 31aB of the stacking surface 31a. In addition, in the left-right direction D3, the length of the first cover portion 66 is longer than the length of the stacking surface 31a, and the length of the second cover portion 34 is longer than the length of the stacking surface 31a. As a result, when viewed in the up-down direction, the entire stacking surface 31a is covered by the first cover portion 66 and the second cover portion 34, effectively preventing toner that has fallen from the intermediate transfer belt 61 from reaching the stacking tray 31.

[0041] In this embodiment, when the second cover portion 34 is located at the second position, the upstream end of the second cover portion 34 in the mounting direction D1 slightly overlaps the downstream end of the first cover portion 66 in the mounting direction D1 as viewed in the vertical direction. The amount of overlap can be set to an appropriate amount, such as 5 mm or 1 cm. This reduces the vertical overlap area between the second cover portion 34 and the first cover portion 66 when the second cover portion 34 is located at, for example, the first position, which is closer to the pulling-out direction D2 than the second position, thereby reducing the height of the image forming apparatus 1. Because the downstream end of the second cover portion 34 slightly overlaps the downstream end of the first cover portion 66, toner falling from the intermediate transfer belt 61 can be prevented from reaching the stacking tray 31 regardless of whether the second cover portion 34 is located at any position between the first and second positions.

[0042] In this embodiment, the case where the downstream end of the second cover portion 34 slightly overlaps the downstream end of the first cover portion 66 has been described, but this is not limiting. For example, the upstream end 34F of the second cover portion 34 in the mounting direction D1 may be configured to substantially coincide with the downstream end 66B of the first cover portion. Here, "substantially coincide" not only refers to a case where the downstream ends are completely butted together in the front-to-rear direction, but also includes a case where they overlap by a small length, for example, about 5 mm.

[0043] In this embodiment, the second cover portion 34, together with the first cover portion 66, covers the top of the stacking tray 31 below the intermediate transfer belt 61 inside the housing 1a, whether the stacking tray 31 is in the normal state or the extended state (see FIGS. 3(b) and 5(b)). This prevents the sheets S stored in the stacking tray 31 from being contaminated by toner remaining on the intermediate transfer belt 61 falling.

[0044] In this embodiment, the second cover portion 34 is supported by the housing 1a so as to be movable between a first position and a second position. When the expanded stacking tray 31 is attached to the housing 1a, the stacking tray 31 presses the second cover portion 34, which is located at the first position, thereby moving the second cover portion 34 from the first position to the second position. When the expanded stacking tray 31 is pulled out of the housing 1a, the stacking tray 31 moves from the second position to the first position due to the biasing force of the elastic member 38 in conjunction with the movement of the stacking tray 31 in the pulling-out direction D2.

[0045] As described above, according to the image forming apparatus 1 of this embodiment, when the second cover portion 34 is located at the first position, the second cover portion 34 has an area Ar1 that is positioned below the intermediate transfer belt 61 in the vertical direction and does not overlap with the first cover portion 66 when viewed in the vertical direction. This makes it possible to provide an area where the first cover portion 66 and the second cover portion 34 do not overlap in the vertical direction, thereby making it possible to reduce the height of the apparatus main body. In other words, by preventing the second cover portion 34 and the first cover portion 66 from overlapping in the vertical direction, the size of the apparatus can be reduced in the vertical direction while preventing contamination of the sheet S inside the apparatus.

[0046] Furthermore, according to the image forming apparatus 1 of this embodiment, the second cover portion 34 is configured to be movable in the mounting direction D1 and the removal direction D2 of the stacking tray 31 in conjunction with the expansion and contraction of the extension portion 36 by utilizing the biasing force of the elastic member 38. Therefore, when the stacking tray 31 does not protrude from the housing 1a, the size of the image forming apparatus 1 in the front-to-rear direction can be reduced while preventing contamination of the sheets S from outside the apparatus. In this way, according to this embodiment, it is possible to achieve both downsizing of the apparatus in the front-to-rear direction and the height direction of the stacking tray 31 while protecting the sheets S stored in the stacking tray 31 from dust and dirt.

[0047] <Second embodiment> Next, a second embodiment of the present invention will be described in detail with reference to Figures 7(a) to 9(b). This embodiment differs from the first embodiment in that the stacking tray 131 and the second cover portion 134 are interlocked in the drawing direction D2 by engaging with each other. However, other configurations are the same as those of the first embodiment, so the same reference numerals will be used and detailed description will be omitted.

[0048] [Configuration of the loading tray and second cover] First, the configuration of the stacking tray 131 will be described with reference to Figures 7(a) and (b). As in the first embodiment, the stacking tray 131 has a tray main body 135 and an extension section 136 supported slidably relative to the tray main body 135 in the mounting direction D1 and the withdrawal direction D2. Figure 7(a) shows a normal state in which the extension section 136 is positioned on the withdrawal direction D2 side and the stacking tray 131 is contracted, and Figure 7(b) shows an expanded state in which the extension section 136 is positioned on the mounting direction D1 side and the stacking tray 131 is expanded. When a user loads long sheets on the stacking tray 131, the user can load them by extending the extension section 136 to expand the storage area for the sheets S.

[0049] Next, the configuration and operation of the second cover portion 134, which is a feature of this embodiment, will be described in detail with reference to Figures 8 to 9(b). First, with reference to Figure 8, a state will be described in which the stacking tray 131 is inserted into and attached to the image forming apparatus 1 in a normal state where the extension portion 136 is not extended. As with the first embodiment, the second cover portion 134 is held by a rail member (not shown) inside the image forming apparatus 1 so as to be movable in the attachment direction D1 and the pull-out direction D2 of the stacking tray 131.

[0050] The second cover portion 134 is movable in the front-rear direction relative to the housing 1a and has a top plate portion 134a and a rear plate portion 134b. The top plate portion 134a has a generally flat plate shape extending horizontally and covering the upper part of the stacking tray 131, protecting the sheets S stored in the stacking tray 131 from dust and dirt. The second cover portion 134 has a cover surface 134c that, together with the first cover portion 66, covers the upper part of the stacking tray 131 in the up-down direction. In this embodiment, the lower surface of the top plate portion 134a forms the cover surface 134c, which covers the upper part of the stacking tray 131. The second cover portion 134 is disposed above the stacking tray 131 and below the intermediate transfer belt 61, and overlaps the stacking surface 31a and the intermediate transfer belt 61 when viewed in the direction of gravity. The rear plate portion 134b has a generally flat plate shape that extends continuously downward from the end portion of the top plate portion 134a on the rear direction B side, and is disposed further rearward in the direction B than the stacking tray 131. The rear plate portion 134b can constitute part of the exterior of the image forming apparatus 1 when it is located on the same plane as the downstream end surface 11a of the housing 1a.

[0051] In this embodiment, the extension portion 136 is provided with a tray-side engaging portion 111 that detachably engages with the second cover portion 134, and the image forming apparatus 1 is provided with a main body-side engaging portion 112 that detachably engages with the second cover portion 134. The second cover portion 134 is further provided with a first cover-side engaging portion 113 that detachably engages with the tray-side engaging portion 111 on the downstream side in the mounting direction D1, and a second cover-side engaging portion 114 that detachably engages with the main body-side engaging portion 112 on the upstream side in the mounting direction D1. The first cover-side engaging portion 113 is an example of an engaging portion. The tray-side engaging portion 111 is an example of an engaged portion, and is engaged with the first cover-side engaging portion 113 when the stacking tray 31 is in the extended state and attached to the housing 1a. The main body-side engaging portion 112 is an example of a restricting portion, and restricts the second cover portion 34 from moving in the drawing direction D2 beyond the first position.

[0052] In this embodiment, the tray-side engaging portion 111 and the first-cover-side engaging portion 113 are formed in a claw-like shape to detachably engage with each other. The tray-side engaging portion 111 and the first-cover-side engaging portion 113 engage when they approach each other and ride up against each other, but are disengaged by applying a predetermined disengagement force in the direction of pulling them apart. Similarly, the main-body-side engaging portion 112 and the second-cover-side engaging portion 114 are formed in a claw-like shape to detachably engage with each other. The main-body-side engaging portion 112 and the second-cover-side engaging portion 114 engage when they approach each other and ride up against each other, but are disengaged by applying a predetermined disengagement force in the direction of pulling them apart. Furthermore, when the second-cover-side engaging portion 114 is engaged with the main-body-side engaging portion 112, the second cover portion 134 cannot move in the drawing direction D2. In other words, the main-body-side engaging portion 112 functions as a stopper that restricts movement of the second cover portion 134 in the drawing direction D2. In this embodiment, the tray side engagement portion 111, the main body side engagement portion 112, the first cover side engagement portion 113, and the second cover side engagement portion 114 are all described as being claw-shaped, but this is not limited to this.

[0053] In the state shown in FIG. 8, the second cover side engaging portion 114 is engaged with the main body side engaging portion 112, and the first cover side engaging portion 113 is engaged with the tray side engaging portion 111. At this time, the second cover portion 134 is held by engaging with the housing 1a and the stacking tray 131 while being housed inside the housing 1a. The rear plate portion 134b of the second cover portion 134 forms the exterior of the image forming apparatus 1. Note that, when the stacking tray 131 is pulled out from the image forming apparatus 1 from the state shown in FIG. 8, the second cover side engaging portion 114 is engaged with the main body side engaging portion 112, and the second cover portion 134 is held by engaging with the housing 1a while being housed inside the housing 1a. Even when the stacking tray 131 is pulled out from the image forming apparatus 1, the second cover portion 134 forms the exterior of the image forming apparatus 1.

[0054] Below the intermediate transfer belt 61, the first cover portion 66 and the second cover portion 134 are disposed to protect the sheets S stored in the stacking tray 131. Similarly to the first embodiment, when the stacking tray 131 is in the mounting position, at least a portion of the second cover portion 134 is located downstream of the first cover downstream end 66B in the mounting direction D1. At least a portion of the second cover portion 134 has an area Ar1 that overlaps the intermediate transfer belt 61 and the stacking surface 31a when viewed in the direction of gravity. That is, when the second cover portion 134 is positioned at the first position, the second cover portion 134 has an area Ar1 that is positioned below the intermediate transfer belt 61 in the vertical direction and does not overlap with the first cover portion 66 when viewed in the vertical direction. When the second cover portion 134 is positioned at the first position, the second cover portion 134 has an area Ar2 that is positioned below the intermediate transfer belt 61 in the vertical direction and overlaps with the first cover portion 66 when viewed in the vertical direction. In addition, the second cover portion 134 and the first cover portion 66 do not overlap, and an area Ar0 is provided where the first cover portion 66 does not exist between the intermediate transfer belt 61 and the stacking tray 131 and the sheet S, and only the second cover portion 134 exists.

[0055] 9(a) and (b), a description will be given of a case where the extension portion 136 of the stacking tray 131 is extended and the stacking tray 131 is inserted into the image forming apparatus 1. Fig. 9(a) shows a state where, when the stacking tray 131 is inserted into the image forming apparatus 1, the tray side engaging portion 111 engages with the first cover side engaging portion 113, and the second cover portion 134 moves together with the stacking tray 131 in the mounting direction D1.

[0056] The insertion of the stacking tray 131 disengages the second cover-side engaging portion 114 from the main body-side engaging portion 112. The disengagement force required to disengage the second cover-side engaging portion 114 from the main body-side engaging portion 112 is set to be weaker than the force required to attach the stacking tray 131. This makes it possible to prevent a decrease in operability when attaching the stacking tray 131. In other words, the user can release the engagement between the second cover-side engaging portion 114 and the main body-side engaging portion 112 by inserting the stacking tray 131 into the housing 1a with a normal operating force.

[0057] 9(b) shows a state in which the extension portion 136 of the stacking tray 131 is extended and the stacking tray 131 has been completely inserted into the image forming apparatus 1. The extension portion 136 and the second cover portion 134 protrude from the rear of the housing 1a in the mounting direction D1, and the second cover portion 134 protects the sheet S protruding outside the housing 1a from dust and dirt.

[0058] At this time, similar to the state shown in FIG. 8 , the first cover portion 66 and the second cover portion 134 are disposed below the intermediate transfer belt 61 so as to protect the sheets S stored in the stacking tray 131. Here, when the stacking tray 131 is in the mounting position, at least a portion of the second cover portion 134 is downstream of the first cover downstream end 66B in the mounting direction D1 and has a portion that overlaps with the intermediate transfer belt 61 and the stacking surface 31a as viewed in the direction of gravity. This portion is designated as area Ar1 as in the case of FIG. 8 . At this time, the upstream end of the second cover portion 134 in the mounting direction D1 is upstream of the first cover downstream end 66B. That is, when the second cover portion 134 is in the second position, the top plate portion 134a of the second cover portion 134 has area Ar1 that is positioned below the intermediate transfer belt 61 in the vertical direction and does not overlap with the first cover portion 66 as viewed in the vertical direction.

[0059] Furthermore, the top panel 134a has an area Ar2 that is positioned below the intermediate transfer belt 61 in the vertical direction and overlaps with the first cover portion 66 when viewed in the vertical direction when the second cover portion 134 is located at the second position. That is, even when the second cover portion 134 is located at the second position, the first cover downstream end 66B, which is the downstream end of the first cover portion 66 in the mounting direction D1, overlaps with the second cover portion 134 when viewed in the direction of gravity. Also, an area Ar0 is provided where the second cover portion 134 and the first cover portion 66 do not overlap with each other when viewed in the vertical direction, and the first cover portion 66 is not present between the intermediate transfer belt 61 and the stacking tray 131 and the sheets S, and only the second cover portion 134 is present.

[0060] 9(b), the second cover portion 134 moves integrally with the stacking tray 131 in the drawing-out direction D2 due to the engagement between the tray-side engaging portion 111 and the first cover-side engaging portion 113. When the drawing operation of the stacking tray 131 is continued further, the main body-side engaging portion 112 and the second cover-side engaging portion 114 engage again, and the movement of the second cover portion 134 in the drawing-out direction D2 is restricted, so that the engagement between the tray-side engaging portion 111 and the first cover-side engaging portion 113 is released.

[0061] Here, the force required to disengage the tray-side engaging portion 111 from the first cover-side engaging portion 113 is set to be weaker than the force required to pull out the stacking tray 131. In this embodiment, the disengagement force required to disengage the tray-side engaging portion 111 from the first cover-side engaging portion 113 is set to be equal to or even weaker than the disengagement force between the main body-side engaging portion 112 and the second cover-side engaging portion 114. This makes it possible to prevent a decrease in operability when pulling out the stacking tray 131. In other words, the user can pull out the stacking tray 131 from the housing 1a with a normal operating force to disengage the tray-side engaging portion 111 from the first cover-side engaging portion 113.

[0062] That is, when the expanded stacking tray 131 is pulled out from the housing 1a, the second cover portion 134 moves from the second position to the first position in conjunction with the movement of the stacking tray 131 in the pulling-out direction D2 due to the engagement between the first cover-side engaging portion 113 and the tray-side engaging portion 111. Then, when the second cover portion 134 reaches the first position, its movement in the pulling-out direction D2 is restricted by the main body-side engaging portion 112, and the engagement between the first cover-side engaging portion 113 and the tray-side engaging portion 111 is released.

[0063] As described above, according to the image forming apparatus 1 of this embodiment, when the second cover portion 134 is located at the first position, the second cover portion 134 has an area Ar1 that is positioned below the intermediate transfer belt 61 in the vertical direction and does not overlap with the first cover portion 66 when viewed in the vertical direction. This makes it possible to provide an area where the first cover portion 66 and the second cover portion 134 do not overlap in the vertical direction, thereby making it possible to reduce the height of the apparatus main body. In other words, by preventing the second cover portion 134 and the first cover portion 66 from overlapping in the vertical direction, the size of the apparatus can be reduced in the vertical direction while preventing contamination of the sheet S inside the apparatus.

[0064] Furthermore, according to the image forming apparatus 1 of this embodiment, when the stacking tray 31 is pulled out from the second position, the second cover portion 134 is pulled into the housing 1a in conjunction with the stacking tray 131 due to the engagement between the first cover side engaging portion 113 and the tray side engaging portion 111. Therefore, there is no need to use a separate member such as an elastic member, and the number of parts can be reduced.

[0065] <Third embodiment> Next, a third embodiment of the present invention will be described in detail with reference to Figures 10(a) to 12(b). This embodiment differs from the first embodiment in that a second cover portion 234 is attached to the stacking tray 231. However, other configurations are the same as those of the first embodiment, so the same reference numerals will be used and detailed description will be omitted.

[0066] [Configuration of the loading tray and second cover] The configuration of the stacking tray 231 will be described with reference to Figures 10(a) and (b). As in the first embodiment, the stacking tray 231 has a tray main body 235 and an extension section 236 supported slidably relative to the tray main body 235 in the mounting direction D1 and the withdrawal direction D2. Figure 10(a) shows a normal state in which the extension section 236 is positioned on the withdrawal direction D2 side and the stacking tray 231 is contracted, and Figure 10(b) shows an expanded state in which the extension section 236 is positioned on the mounting direction D1 side and the stacking tray 231 is expanded. When a user loads long sheets on the stacking tray 231, the user can load the sheets by extending the extension section 236 to expand the storage area for the sheets S.

[0067] 11 to 12(b), the configuration and operation of the second cover portion 234, which is a feature of this embodiment, will be described in detail. First, with reference to Fig. 11, a state in which the extension portion 236 of the stacking tray 231 is in a normal state where it is not extended and is inserted into and attached to the image forming apparatus 1 will be described.

[0068] The second cover portion 234 is movable in the front-rear direction relative to the housing 1a and has a top plate portion 234a and a rear plate portion 234b. The top plate portion 234a has a generally flat plate shape extending horizontally and covering the upper part of the stacking tray 231, protecting the sheets S stored in the stacking tray 231 from dust and dirt. The second cover portion 234 has a cover surface 234c that, together with the first cover portion 66, covers the upper part of the stacking tray 231 in the up-down direction. In this embodiment, the lower surface of the top plate portion 234a is the cover surface 234c, which covers the upper part of the stacking tray 231. The second cover portion 234 is disposed above the stacking tray 31 and below the intermediate transfer belt 61, and overlaps the stacking surface 31a and the intermediate transfer belt 61 when viewed in the direction of gravity. The rear plate portion 234b has a generally flat plate shape that extends continuously downward from the end portion of the top plate portion 234a on the rear direction B side, and is disposed further rearward in the direction B than the stacking tray 231. The rear plate portion 234b can constitute part of the exterior of the image forming apparatus 1 when it is located on the same plane as the downstream end surface 11a of the housing 1a.

[0069] In this embodiment, the extension portion 236 is provided with a tray-side engagement portion 211 that detachably engages with the second cover portion 234, and the second cover portion 234 is provided with a cover-side engagement portion 212 that detachably engages with the tray-side engagement portion 211. The cover-side engagement portion 212 is pin-shaped with its longitudinal direction extending vertically, and the tray-side engagement portion 211 is formed as a through-hole into which the pin-shaped cover-side engagement portion 212 penetrates vertically to engage. Before attaching the stacking tray 231 to the housing 1a, the user attaches the second cover portion 234 to the extension portion 236 of the stacking tray 231 in advance, and then attaches the stacking tray 231 with the attached second cover portion 234 to the housing 1a. Furthermore, when the stacking tray 231 attached to the housing 1a is pulled out, the second cover portion 234 is also pulled out as the stacking tray 231 moves. In this embodiment, unlike the first and second embodiments, there is no coupling or engagement relationship between the second cover portion 234 and the housing 1a.

[0070] The rear plate 234b of the second cover portion 234 forms the exterior of the image forming apparatus 1. Even when the stacking tray 231 is pulled out from the image forming apparatus 1, the second cover portion 234 forms the exterior of the image forming apparatus 1.

[0071] Below the intermediate transfer belt 61, the first cover portion 66 and the second cover portion 234 are disposed to protect the sheets S stored in the stacking tray 231. Similarly to the first embodiment, when the stacking tray 231 is in the mounting position, at least a portion of the second cover portion 234 is downstream of the first cover downstream end 66B in the mounting direction D1. At least a portion of the second cover portion 234 has an area Ar1 that overlaps the intermediate transfer belt 61 and the stacking surface 31a when viewed in the direction of gravity. That is, when the second cover portion 234 is positioned at the first position, the second cover portion 234 has an area Ar1 that is positioned below the intermediate transfer belt 61 in the vertical direction and does not overlap with the first cover portion 66 when viewed in the vertical direction. When the second cover portion 234 is positioned at the first position, the second cover portion 234 has an area Ar2 that is positioned below the intermediate transfer belt 61 in the vertical direction and overlaps with the first cover portion 66 when viewed in the vertical direction. In addition, the second cover portion 234 and the first cover portion 66 do not overlap, and an area Ar0 is provided where the first cover portion 66 does not exist between the intermediate transfer belt 61 and the stacking tray 231 and the sheet S, and only the second cover portion 234 exists.

[0072] 12(a) and 12(b), a case where the stacking tray 231 is inserted into the image forming apparatus 1 with the extension portion 236 extended will be described. As in the case shown in Fig. 11, the second cover portion 234 is attached to the extension portion 236 of the stacking tray 231 by engagement between the cover-side engaging portion 212 and the tray-side engaging portion 211 before the insertion operation. Fig. 12(a) shows a state where, when the stacking tray 231 is inserted into the image forming apparatus 1, the cover-side engaging portion 212 is engaged with the tray-side engaging portion 211, and the second cover portion 234 moves together with the stacking tray 231 in the mounting direction D1.

[0073] 12(b) shows a state in which the extension portion 236 of the stacking tray 231 is extended and the stacking tray 231 has been completely inserted into the image forming apparatus 1. The extension portion 236 and the second cover portion 234 protrude from the rear of the housing 1a in the mounting direction D1, and the second cover portion 234 protects the sheet S protruding outside the housing 1a from dust and dirt.

[0074] 11, the first cover portion 66 and the second cover portion 234 are disposed below the intermediate transfer belt 61 to protect the sheets S stored in the stacking tray 231. When the stacking tray 231 is in the mounting position, at least a portion of the second cover portion 234 is downstream of the first cover downstream end 66B in the mounting direction D1 and has a portion that overlaps with the intermediate transfer belt 61 and the stacking surface 31a as viewed in the direction of gravity. This portion is designated as area Ar1 as in the case of FIG. 11. At this time, the upstream end of the second cover portion 234 in the mounting direction D1 is upstream of the first cover downstream end 66B. That is, when the second cover portion 234 is in the second position, the top plate portion 234a of the second cover portion 234 has area Ar1 that is positioned below the intermediate transfer belt 61 in the vertical direction and does not overlap with the first cover portion 66 as viewed in the vertical direction.

[0075] Furthermore, the top panel 234a has an area Ar2 that is positioned below the intermediate transfer belt 61 in the vertical direction and overlaps with the first cover portion 66 when viewed in the vertical direction when the second cover portion 234 is located at the second position. That is, even when the second cover portion 234 is located at the second position, the first cover downstream end 66B, which is the downstream end of the first cover portion 66 in the mounting direction D1, overlaps with the second cover portion 234 when viewed in the direction of gravity. Also, an area Ar0 is provided where the second cover portion 234 and the first cover portion 66 do not overlap with each other when viewed in the vertical direction, and the first cover portion 66 is not present between the intermediate transfer belt 61 and the stacking tray 231 and the sheets S, and only the second cover portion 234 is present.

[0076] As described above, according to the image forming apparatus 1 of this embodiment, when the second cover portion 234 is located at the first position, the second cover portion 234 has an area Ar1 that is positioned below the intermediate transfer belt 61 in the vertical direction and does not overlap with the first cover portion 66 when viewed in the vertical direction. This makes it possible to provide an area where the first cover portion 66 and the second cover portion 234 do not overlap in the vertical direction, thereby making it possible to reduce the height of the apparatus main body. In other words, by preventing the second cover portion 234 and the first cover portion 66 from overlapping in the vertical direction, the size of the apparatus can be reduced in the vertical direction while preventing contamination of the sheet S inside the apparatus.

[0077] Furthermore, according to the image forming apparatus 1 of this embodiment, the second cover portion 234 is attached to the stacking tray 231, so that a separate member such as an elastic member is not required, and the structure of the housing 1a can be prevented from becoming complicated.

[0078] In the present embodiment, the pin-shaped cover-side engaging portion 212 is inserted into the tray-side engaging portion 211 formed as a through-hole, thereby detachably attaching the second cover portion 234 to the extension portion 236 of the stacking tray 231. However, the present invention is not limited to this. For example, the cover-side engaging portion 212 and the tray-side engaging portion 211 may be configured as claws that engage with each other, like the tray-side engaging portion 111 and the first cover-side engaging portion 113 shown in the second embodiment. Alternatively, the second cover portion 234 may be configured to be unable to be removed from the extension portion 236 of the stacking tray 231. In this case, for example, to facilitate the operation of stacking sheets S on the stacking tray 231, a rotation center of the second cover portion 234 may be provided with respect to the extension portion 236, thereby configuring the second cover portion 234 to be rotatable. Alternatively, the second cover portion 234 and the extension portion 236 may be configured to be fixed integrally.

[0079] <Other embodiments> In the above-described embodiments, the first cover portion 66 is described as being made of a flat plate-like member. However, this is not limited thereto, and the first cover portion 66 may be made of, for example, a flexible film-like sheet. Alternatively, the portion of the first cover portion 66 on the pulling-out direction D2 side may be made of a flat plate-like member, and the other portion on the mounting direction D1 side may be made of a flexible film-like sheet. In this case, by making the region of the first cover portion 66 that overlaps with the second cover portion 34, 134, 234 out of a film-like sheet, the vertical size of the first cover portion 66 can be made smaller than when the entire first cover portion 66 is made of a flat plate-like member.

[0080] In the above-described embodiments, the second cover portion 34, 134, 234 includes a top panel portion 34a, 134a, 234a and a rear panel portion 34b, 134b, 234b. However, this is not limited to this. For example, as long as at least the top panel portion 34a, 134a, 234a is provided, dust protection from above can be achieved even if the rear panel portion 34b, 134b, 234b is not provided. In the above-described embodiments, the top panel portion 34a, 134a, 234a has a generally flat plate shape, but this is not limited to this. For example, a portion of the top panel portion 34a, 134a, 234a that overlaps with the first cover portion 66 may be made of a film-like sheet. In this case, the vertical size can be further reduced compared to when the entire top panel portion 34a, 134a, 234a has a generally flat plate shape.

[0081] In addition, in the above-described embodiments, the second cover portion 34, 134, 234 is located inside the housing 1a at the first position, but this is not limiting. For example, the first position may be a position where the downstream end of the second cover portion 34, 134, 234 in the mounting direction D1 protrudes from the housing 1a.

[0082] Furthermore, in the above-described embodiments, the second cover portion 34, 134, 234 is described as having only a portion protruding outward from the housing 1a in the second position, but this is not limited thereto. For example, the entire second cover portion 34, 134, 234 may protrude outward from the housing 1a. For example, the second position may be a position where, when viewed from the top-bottom direction, the end of the second cover portion 34, 134, 234 in the pulling-out direction D2 coincides with the rear cover 11B. Alternatively, the second position may be a position where the end of the second cover portion 34, 134, 234 is spaced apart from the rear cover 11B in the mounting direction D1.

[0083] In addition, in each of the above-described embodiments, the second cover portion 34, 134, 234 partially protrudes from the housing 1a when in the second position, but this is not limiting. For example, the second cover portion 34, 134, 234 may be entirely located inside the housing 1a when in the second position.

[0084] In addition, in each of the above-described embodiments, the second cover portion 34, 134, 234 has the area Ar2 that overlaps with the first cover portion 66 in the first position, but this is not limited to this. For example, the second cover portion 34, 134, 234 may not overlap with the first cover portion 66 in the first position.

[0085] The disclosure of the present embodiment also includes the following configuration examples and method examples. (Configuration 1) The housing and a photoreceptor on which a toner image is formed; a storage section having a loading surface for loading sheets and configured to store the sheets, the storage section being configured to take a pulled-out position where it is pulled out from the housing and a loaded position where it is loaded into the housing by being moved from the pulled-out position in a loading direction; a feeding section that feeds the sheets stored in the storage section; a transfer belt disposed above the storage unit, the transfer belt receiving the toner image from the photosensitive member and transferring the toner image onto a sheet fed by the feeding unit; a first cover portion disposed above the storage portion and below the transfer belt, the first cover portion overlapping the stacking surface and the transfer belt when viewed in the direction of gravity; a second cover portion disposed above the storage portion and below the transfer belt, the second cover portion overlapping the stacking surface and the transfer belt when viewed in the direction of gravity; Equipped with the storage section has a main body section and an expansion section provided so as to be movable in the mounting direction relative to the main body section, the storage section is displaceable between a first state in which the length of the storage section in the mounting direction is a first length and a second state in which the extension section is moved in the mounting direction relative to the main body section and the length of the storage section in the mounting direction is a second length longer than the first length, When the accommodation unit moves from the drawn-out position to the attached position in the second state, the second cover unit moves in the attached direction in accordance with the movement of the accommodation unit, a downstream end of the housing in the mounting direction; When the accommodation portion is located at the mounting position in the second state, a portion of the accommodation portion is located downstream of the downstream end of the housing in the mounting direction, and the second cover portion covers the portion of the accommodation portion from above, a downstream end of the first cover portion in the mounting direction is a first cover downstream end; When the storage unit is in the mounting position, at least a part of the second cover unit is located downstream of the downstream end of the first cover unit in the mounting direction and has a part that overlaps the transfer belt and the stacking surface when viewed in the gravity direction. An image forming apparatus characterized by: (Configuration 2) the photosensitive member is a photosensitive drum, In the rotation axis direction of the photosensitive drum, the length of the first cover portion is longer than the length of the loading surface. 2. The image forming apparatus according to claim 1, (Configuration 3) the photosensitive member is a photosensitive drum, In the rotation axis direction of the photosensitive drum, the length of the second cover portion is longer than the length of the loading surface. 3. The image forming apparatus according to claim 1, wherein: (Configuration 4) the photosensitive member is a photosensitive drum, the housing has side walls on both sides in the direction of the rotation axis of the photosensitive drum, The first cover is supported at both sides in the rotation axis direction by the side walls of the housing. 4. The image forming apparatus according to any one of configurations 1 to 3. (Configuration 5) A downstream end of the first cover portion in the mounting direction overlaps with the second cover portion when viewed in the gravity direction. 5. The image forming apparatus according to any one of configurations 1 to 4. (Configuration 6) When the storage unit is in the mounting position, an upstream end of the first cover portion in the mounting direction is located upstream of an upstream end of the loading surface; A downstream end of the second cover portion in the mounting direction is located downstream of a downstream end of the loading surface. 6. The image forming apparatus according to any one of configurations 1 to 5. (Configuration 7) the second cover portion, together with the first cover portion, covers an upper portion of the storage portion below the transfer belt inside the housing regardless of whether the storage portion is in the first state or the second state. 7. The image forming apparatus according to any one of configurations 1 to 6. (Configuration 8) The second cover portion has a side plate portion extending in a vertical direction at a downstream portion in the mounting direction, the side plate portion constitutes a part of a downstream end portion of the image forming apparatus in the mounting direction; 8. The image forming apparatus according to any one of configurations 1 to 7. (Configuration 9) When the storage unit in the first state is at the mounting position, an outer surface of the side plate portion is flush with the downstream end of the housing; 9. The image forming apparatus according to configuration 8, (Configuration 10) the transfer belt is stretched between a first roller and a second roller disposed downstream of the first roller in the mounting direction; When viewed in the gravity direction, the first roller overlaps the first cover portion but does not overlap the second cover portion, and the second roller overlaps the second cover portion but does not overlap the first cover portion. 10. The image forming apparatus according to any one of configurations 1 to 9. (Configuration 11) a primary transfer unit that primarily transfers the toner image carried on the photosensitive member onto the transfer belt; a secondary transfer unit that transfers the toner image that has been primarily transferred onto the transfer belt onto a sheet fed by the feeding unit, the photosensitive member is disposed above the transfer belt in the direction of gravity; 11. The image forming apparatus according to any one of configurations 1 to 10. (Configuration 12) the mounting direction is a direction from downstream to upstream of a feeding direction in which the feeding unit feeds the sheets; 12. The image forming apparatus according to any one of configurations 1 to 11. (Configuration 13) The mounting direction is a direction along the horizontal direction. 13. The image forming apparatus according to any one of configurations 1 to 12. (Configuration 14) the second cover portion is movably supported by the housing at a first position and a second position located downstream of the first position in the mounting direction and protruding downstream of the housing downstream end in the mounting direction, When the accommodation unit in the second state is attached to the housing, the accommodation unit presses the second cover unit located at the first position, thereby moving the second cover unit from the first position to the second position. 14. The image forming apparatus according to any one of configurations 1 to 13. (Configuration 15) a biasing portion that biases the second cover portion toward the first position, When the accommodation portion in the second state is pulled out from the housing, the second cover portion moves from the second position to the first position by the biasing force of the biasing portion in conjunction with the accommodation portion moving upstream in the mounting direction. 15. The image forming apparatus according to configuration 14. (Configuration 16) the second cover portion has an engaging portion, the accommodation portion has an engaged portion with which the engaging portion engages when the accommodation portion is in the second state and at the attached position, the housing has a restricting portion that restricts the second cover portion from moving upstream in the mounting direction from a first position, When the accommodation portion in the second state is pulled out from the housing, the second cover portion moves from the second position to the first position in conjunction with the accommodation portion moving upstream in the mounting direction due to the engagement between the engaging portion and the engaged portion, and when the second cover portion reaches the first position, the upstream movement in the mounting direction is restricted by the restricting portion, and the engagement between the engaging portion and the engaged portion is released. 15. The image forming apparatus according to configuration 14. (Configuration 17) The second cover portion is attached to the storage portion. 17. The image forming apparatus according to any one of configurations 1 to 16. [Explanation of symbols]

[0086] 1: Image forming apparatus / 1a: Housing / 11a: Downstream end surface (downstream end of housing) / 11L: Left side wall (side wall) / 11R: Right side wall (side wall) / 22: Photosensitive drum (photosensitive member) / 31, 131, 231: Loading tray (storage section) / 32: Feeding roller (feeding section) / 34, 134, 234: Second cover section / 34b, 134b, 234b: Rear plate section (side plate section) / 35, 135, 235: Tray main body (main body section) / 36, 136, 236: Extension section / 51: Primary transfer section / 38: Elastic member (urging section) / 52: Secondary transfer section / 61: Intermediate transfer belt (transfer belt) / 64: Drive roller (first roller) / 65: Tension roller (second roller) / 66: First cover section / 66B: Downstream end of first cover / 111: Tray side engagement section (engaged section) / 112: Main body side engagement section (regulating section) / 113: First cover side engagement section (engaging section) / D1: Mounting direction / L1: First length / L2: Second length

Claims

1. The housing and a photoreceptor on which a toner image is formed; a storage section having a loading surface for loading sheets and configured to store the sheets, the storage section being configured to take a pulled-out position where it is pulled out from the housing and a loaded position where it is loaded into the housing by being moved from the pulled-out position in a loading direction; a feeding section that feeds the sheets stored in the storage section; a transfer belt disposed above the storage unit, the transfer belt receiving the toner image from the photosensitive member and transferring the toner image onto a sheet fed by the feeding unit; a first cover portion disposed above the storage portion and below the transfer belt, the first cover portion overlapping the stacking surface and the transfer belt when viewed in the direction of gravity; a second cover portion disposed above the storage portion and below the transfer belt, the second cover portion overlapping the stacking surface and the transfer belt when viewed in the direction of gravity; Equipped with the storage section has a main body section and an expansion section provided so as to be movable in the mounting direction relative to the main body section, the storage portion is displaceable between a first state in which the length of the storage portion in the mounting direction is a first length and a second state in which the extension portion is moved in the mounting direction relative to the main body portion and the length of the storage portion in the mounting direction is a second length longer than the first length, When the accommodation portion moves from the drawn-out position to the attached position in the second state, the second cover portion moves in the attached direction in accordance with the movement of the accommodation portion, a downstream end of the housing in the mounting direction; When the accommodation portion is located at the mounting position in the second state, a portion of the accommodation portion is located downstream of the downstream end of the housing in the mounting direction, and the second cover portion covers the portion of the accommodation portion from above, a downstream end of the first cover portion in the mounting direction is a first cover downstream end; When the storage unit is in the mounting position, at least a part of the second cover unit is located downstream of the downstream end of the first cover unit in the mounting direction and has a part that overlaps the transfer belt and the stacking surface when viewed in the gravity direction. An image forming apparatus characterized by:

2. the photosensitive member is a photosensitive drum, In the rotation axis direction of the photosensitive drum, the length of the first cover portion is longer than the length of the loading surface.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

3. the photosensitive member is a photosensitive drum, In the rotation axis direction of the photosensitive drum, the length of the second cover portion is longer than the length of the loading surface.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

4. the photosensitive member is a photosensitive drum, the housing has side walls on both sides in the direction of the rotation axis of the photosensitive drum, The first cover is supported at both sides in the rotation axis direction by the side walls of the housing.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

5. A downstream end of the first cover portion in the mounting direction overlaps with the second cover portion when viewed in the gravity direction.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

6. When the storage unit is in the mounting position, an upstream end of the first cover portion in the mounting direction is located upstream of an upstream end of the loading surface; A downstream end of the second cover portion in the mounting direction is located downstream of a downstream end of the loading surface.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

7. the second cover portion, together with the first cover portion, covers an upper portion of the storage portion below the transfer belt inside the housing regardless of whether the storage portion is in the first state or the second state.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

8. The second cover portion has a side plate portion extending in a vertical direction at a downstream portion in the mounting direction, the side plate portion constitutes a part of a downstream end portion of the image forming apparatus in the mounting direction; 2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

9. When the storage unit in the first state is at the mounting position, an outer surface of the side plate portion is flush with the downstream end of the housing; 9. The image forming apparatus according to claim 8,

10. the transfer belt is stretched between a first roller and a second roller disposed downstream of the first roller in the mounting direction; When viewed in the gravity direction, the first roller overlaps the first cover portion but does not overlap the second cover portion, and the second roller overlaps the second cover portion but does not overlap the first cover portion.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

11. a primary transfer unit that primarily transfers the toner image carried on the photosensitive member onto the transfer belt; a secondary transfer unit that transfers the toner image that has been primarily transferred onto the transfer belt onto a sheet fed by the feeding unit, the photosensitive member is disposed above the transfer belt in the direction of gravity; 2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

12. the mounting direction is a direction from downstream to upstream of a feeding direction in which the feeding unit feeds the sheets; 2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

13. The mounting direction is a direction along the horizontal direction.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

14. the second cover portion is movably supported by the housing at a first position and a second position located downstream of the first position in the mounting direction and protruding downstream of the housing downstream end in the mounting direction, When the accommodation unit in the second state is attached to the housing, the accommodation unit presses the second cover unit located at the first position, thereby moving the second cover unit from the first position to the second position.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

15. a biasing portion that biases the second cover portion toward the first position, When the accommodation portion in the second state is pulled out from the housing, the second cover portion moves from the second position to the first position by the biasing force of the biasing portion in conjunction with the accommodation portion moving upstream in the mounting direction.

15. The image forming apparatus according to claim 14.

16. the second cover portion has an engaging portion, the accommodation portion has an engaged portion with which the engaging portion engages when the accommodation portion is in the second state and at the attached position, the housing has a restricting portion that restricts the second cover portion from moving upstream in the mounting direction from a first position, When the accommodation portion in the second state is pulled out from the housing, the second cover portion moves from the second position to the first position in conjunction with the accommodation portion moving upstream in the mounting direction due to the engagement between the engaging portion and the engaged portion, and when the second cover portion reaches the first position, the upstream movement in the mounting direction is restricted by the restricting portion, and the engagement between the engaging portion and the engaged portion is released.

15. The image forming apparatus according to claim 14.

17. The second cover portion is attached to the storage portion.

2. The image forming apparatus according to claim 1, wherein the image forming apparatus is a recording medium.

Images