Paper ejection stacking device and image forming system

Abstract

This reduces paper stacking errors compared to a configuration in which the upper end of the shock absorbing portion protrudes from the surface of the rear wall of the tray when viewed from the side. [Solution] The paper discharge stacking device is provided with a tray that is positioned below the discharge outlet for discharging paper and that loads the paper discharged from the discharge outlet in a position where the front end of the paper is positioned higher than the rear end, and a shock absorbing section that is provided on the rear wall of the tray and receives the rear end of the paper loaded on the tray to absorb the impact caused by the paper colliding with the tray, the shock absorbing section having a slope that extends diagonally downward in the direction in which the paper is discharged when viewed from the side and intersects with the surface of the rear wall.

Description

[Technical Field]

[0001] The present disclosure relates to a discharge sheet stacking device and an image forming system. [Background technology]

[0002] Patent Document 1 discloses a paper receiving device. This paper receiving device has an end fence and a loading table. The leading edge of a sheet of paper discharged from the discharge port collides with the end fence. The loading table is where the sheets that collide and fall are stacked. In the paper receiving device, the end fence has an impact absorbing section at its upper part that absorbs the impact of the sheet of paper colliding. The end fence also has a paper alignment section at its lower part that regulates the leading edge of the sheet that collides with the impact absorbing section and falls.

[0003] Patent Document 2 discloses a discharged paper stacking device. This discharged paper stacking device includes a stacking means and a deformation means. The stacking means stacks discharged print media on a discharged paper tray section having a stacking surface. The deformation means deforms a portion of the wall surface of the discharged paper tray section that contacts the print media in accordance with the thickness of the print media.

[0004] Patent Document 3 discloses an image forming apparatus. This image forming apparatus includes a paper feeder, a paper transport path, and an image forming unit. The paper transport path transports paper fed from the paper feeder to various parts of the apparatus body. The image forming unit forms an image on paper transported via the paper transport path. The image forming apparatus also includes a paper transport surface that forms the paper transport path, with multiple ribs protruding along the transport direction, a sound-absorbing member that fills at least some of the gaps between the ribs, and a sheet material that covers the sound-absorbing member and the ribs. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2019-137533 [Patent Document 2] Japanese Patent Application Laid-Open No. 2016-183020 [Patent Document 3] Japanese Patent Application Laid-Open No. 2009-83957 Summary of the Invention [Problem to be solved by the invention]

[0006] The present disclosure aims to reduce sheet loading errors compared to a configuration in which the upper end of the shock absorbing portion protrudes from the surface of the rear wall of the tray when viewed from the side. [Means for solving the problem]

[0007] A first aspect of the paper output stacking device of the present disclosure includes a tray that is positioned below an outlet for discharging paper and that loads the paper discharged from the outlet in a position where the front end of the paper is positioned higher than the rear end of the paper, and an impact absorbing section that is provided on the rear wall of the tray and receives the rear end of the paper loaded on the tray and absorbs the impact caused by the paper colliding with the tray, the impact absorbing section having a slope that extends diagonally downward in the paper discharge direction when viewed from the side and intersects with the surface of the rear wall.

[0008] A second aspect of the present disclosure provides a discharged paper stacking device according to the first aspect, wherein the shock absorbing sections are provided at intervals in a width direction of the discharge opening.

[0009] A third aspect of the present disclosure provides a discharged paper stacking device according to the first aspect, wherein the shock absorbing sections are disposed on both sides of the discharge opening in the width direction.

[0010] A fourth aspect of the present disclosure provides a discharged paper stacking device according to the third aspect, wherein the shock absorbing section is disposed on a center line of the discharge outlet in a width direction.

[0011] A fifth aspect of the present disclosure is a paper output stacking device in which, in the paper output stacking device described in the first aspect, the rear wall is configured to include a wall main body and a pair of ribs protruding from the wall main body and extending downward, the shock absorbing portion is provided between the pair of ribs, and the inclined surface intersects with the top surface of the ribs included on the surface of the rear wall when viewed from the side.

[0012] A sixth aspect of the present disclosure is a paper output stacking device in which, in the paper output stacking device described in the fifth aspect, the shock absorbing portion is a sheet-like member, and the tray is provided with a support surface between the pair of ribs that supports the shock absorbing portion so that it is inclined diagonally downward toward the paper output direction when viewed from the side.

[0013] A seventh aspect of the present disclosure is a paper output stacking device in which, in the paper output stacking device described in the first aspect, the shock absorbing portion is a sheet-like member, the rear wall is provided with a storage recess that stores at least the upper end portion of the shock absorbing portion, and the tray is provided with a support surface that supports the shock absorbing portion so that it slopes diagonally downward in the paper output direction from the storage recess to the bottom of the tray when viewed from the side.

[0014] An eighth aspect of the present disclosure is a paper output stacking device in which, in the paper output stacking device described in the first aspect, the shock absorbing portion is formed of a sheet-shaped cushioning material, and one side of the cushioning material is attached to the rear wall.

[0015] A ninth aspect of the present disclosure provides a paper output stacking device according to the eighth aspect, wherein a film having a lower friction resistance than the cushion material is attached to a surface of the cushion material opposite the rear wall.

[0016] An image forming system according to a tenth aspect of the present disclosure includes an image forming unit that forms an image on paper, an outlet that discharges the paper on which the image has been formed by the image forming unit, and a paper discharge stacking device according to any one of the first to ninth aspects that stacks the paper discharged from the outlet. [Effects of the Invention]

[0017] The discharged paper stacking device according to the first aspect of the present disclosure can suppress improper paper stacking compared to a configuration in which the upper end of the shock absorbing portion protrudes from the surface of the rear wall of the tray when viewed from the side.

[0018] In the discharged paper stacking device according to the second aspect of the present disclosure, the shock absorbing section can receive the trailing ends of paper sheets of two or more different sizes.

[0019] In the discharged paper stacking device according to the third aspect of the present disclosure, the shock absorbing section can receive the rear end of the paper discharged from the discharge port on both sides in the width direction of the discharge port.

[0020] In the discharged paper stacking device according to the fourth aspect of the present disclosure, the shock absorbing section can receive the trailing ends of paper sheets of two or more different sizes.

[0021] In the discharged paper stacking device of the fifth aspect of the present disclosure, the variation in the position of the shock absorbing portion in the width direction of the discharge outlet can be reduced compared to a configuration in which the surface of the rear wall is flat and the shock absorbing portion is provided on the flat surface.

[0022] In the discharged paper stacking device according to the sixth aspect of the present disclosure, a general-purpose sheet-like member can be used as the shock absorbing section.

[0023] In the discharged paper stacking device according to the seventh aspect of the present disclosure, a general-purpose sheet-like member can be used as the shock absorbing section.

[0024] In the discharged paper stacking device according to the eighth aspect of the present disclosure, the cushioning material can be attached to the rear wall of the tray more easily than in a configuration in which the cushioning material is attached to the rear wall of the tray using a dedicated part.

[0025] The discharged paper stacking device according to the ninth aspect of the present disclosure can suppress improper paper stacking compared to a configuration in which a film having the same or higher friction resistance than the cushioning material is attached.

[0026] In the image forming system according to the tenth aspect of the present disclosure, it is possible to prevent improper stacking of sheets discharged from the discharge port. [Brief explanation of the drawings]

[0027] [Figure 1] 1 is a schematic configuration diagram illustrating an image forming apparatus according to an embodiment of the present disclosure. [Figure 2] 1 is a schematic configuration diagram illustrating an image forming unit included in an image forming apparatus according to an embodiment of the present disclosure. [Figure 3] 1 is a perspective view illustrating an output sheet stacking device according to an embodiment of the present disclosure. [Figure 4] FIG. 4 is an enlarged view of the portion indicated by arrow 4X in FIG. 3. [Figure 5] 4 is a front view of the rear wall of the tray shown in FIG. 3, seen from the opposite direction to the paper ejection direction. [Figure 6] 6 is a cross-sectional view taken along line 6X-6X in FIG. 4. [Figure 7] FIG. 7 is a cross-sectional view taken along line 7X-7X in FIG. [Figure 8] 7 is a cross-sectional view corresponding to FIG. 6, illustrating the behavior of the paper P discharged from the discharge port. [Figure 9] 7 is a cross-sectional view corresponding to FIG. 6, illustrating the behavior of the paper P discharged from the discharge port. [Figure 10] FIG. 10 is a front view of a rear wall of a tray in an output paper stacking device according to another embodiment of the present disclosure, viewed from the opposite direction to the paper ejection direction. [Figure 11] FIG. 10 is a cross-sectional view of a shock absorbing portion in a discharged paper stacking device according to another embodiment of the present disclosure. [Figure 12] 10 is a cross-sectional view (a cross-sectional view corresponding to FIG. 6) of a main part of a discharged paper stacking device according to another embodiment of the present disclosure. [Figure 13] 10 is a cross-sectional view (a cross-sectional view corresponding to FIG. 7) of a shock absorbing portion in a discharged paper stacking device according to another embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0028] An example of a paper discharge stacking device and an image forming apparatus according to an embodiment of the present disclosure will be described with reference to Figs. 1 to 9. Note that arrow H shown in each figure indicates the vertical direction, i.e., the up-down direction of the apparatus. Arrow W is perpendicular to arrow H and is horizontal, indicating the width direction of the apparatus. Arrow D is perpendicular to arrows H and W and is horizontal, indicating the depth direction of the apparatus. The image forming apparatus of this embodiment is an example of an image forming system according to the present disclosure.

[0029] (Overall configuration of image forming apparatus 10) As shown in FIG. 1, the image forming apparatus 10 includes an image forming unit 12, a discharge port 78, and a discharged paper stacking device 80. The image forming unit 12 has the function of forming an image (toner image) on paper P as a recording medium. The discharge port 78 is an opening through which paper P on which an image has been formed by the image forming unit 12 is discharged to the outside of the apparatus main body 10a. This discharge port 78 is an opening that extends in the depth direction of the apparatus. Hereinafter, the direction in which the discharge port 78 extends (the depth direction of the apparatus) will be referred to as the width direction of the discharge port 78. The discharged paper stacking device 80 has the function of stacking paper discharged from the discharge port 78.

[0030] The image forming apparatus 10 also includes an image reading unit 60, a conveying device 14, a storage unit 18, and a control unit 28. The image reading unit 60 has a function of reading an image from a document. The conveying device 14 has a function of conveying paper P along a conveying path 14a. The storage unit 18 has a function of storing paper P. The control unit 28 has a function of controlling the entire image forming apparatus 10.

[0031] In the image forming apparatus 10, the paper P stored in the storage unit 18 is transported along the transport path 14a by the transport device 14. In the image forming unit 12, a toner image is formed on the paper P transported by the transport device 14 based on image data. The paper P on which the toner image has been formed is discharged by the transport device 14 to the outside of the apparatus main body 10a through the discharge opening 78. The discharged paper P is stacked on the discharged paper stacking device 80. The image data may be image data read by the image reading unit 60 or may be image data received from another device or the like.

[0032] [Image forming unit 12] 1, the image forming unit 12 includes a plurality of toner image forming units 30 that respectively form toner images of each color. The image forming unit 12 also includes a transfer unit 32 that transfers the toner images formed in the toner image forming units 30 onto paper P. The image forming unit 12 also includes a fixing device 34 that fixes the toner images transferred onto paper P by the transfer units 32 onto paper P.

[0033] -Toner image forming unit 30- A plurality of toner image forming units 30 are provided to form toner images for each color. In this embodiment, toner image forming units 30Y, 30M, 30C, and 30K are provided for a total of four colors: yellow (Y), magenta (M), cyan (C), and black (K). In the following description, when there is no need to distinguish between yellow (Y), magenta (M), cyan (C), and black (K), the Y, M, C, and K attached to the reference numerals will be omitted.

[0034] The toner image forming units 30 for each color are basically configured the same except for the toner used. As shown in FIG. 2, the toner image forming units 30 include an image carrier 36, a charger 42, an exposure device 44, and a developing device 46. The image carrier 36 is a rotating cylindrical body that holds a toner image on its outer periphery. The charger 42 charges the image carrier 36. The exposure device 44 irradiates the charged image carrier 36 with exposure light to form an electrostatic latent image. The developing device 46 develops the electrostatic latent image into a toner image using developer G containing toner. The toner image forming units 30 for each color form images of the respective colors using toner of the respective colors.

[0035] 1, the image carriers 36 of each color are in contact with a rotating transfer belt 50 (described in detail later). In the rotation direction of the transfer belt 50 (see the arrow in FIG. 1), the toner image forming units 30 of yellow (Y), magenta (M), cyan (C), and black (K) are arranged in this order from the upstream side.

[0036] -Transfer section 32- 1, the transfer unit 32 includes an endless transfer belt 50 and primary transfer rolls 52. The primary transfer rolls 52 are disposed on opposite sides of the transfer belt 50 from the image carriers 36 of the respective colors. The primary transfer rolls 52 function to transfer the toner images formed on the image carriers 36 of the respective colors to the transfer belt 50.

[0037] The transfer unit 32 includes a winding roll 56 and a driving roll 58. The transfer belt 50 is wound around the winding roll 56. The transfer belt 50 is wound around the driving roll 58, which has the function of transmitting a rotational force to the transfer belt 50. The rotation of the driving roll 58 causes the transfer belt 50 to rotate in the direction of the arrow in FIG. 1.

[0038] The transfer unit 32 includes a secondary transfer roll 54. The secondary transfer roll 54 is disposed on the opposite side of the transfer belt 50 from the winding roll 56. The secondary transfer roll 54 has a function of transferring the toner image transferred onto the transfer belt 50 onto the paper P. A transfer nip NT for transferring the toner image onto the paper P is formed between the secondary transfer roll 54 and the transfer belt 50.

[0039] -Fusing unit 34- 1, the fixing device 34 is disposed downstream of the transfer nip NT in the transport direction of the paper P. The fixing device 34 has a function of fixing the toner image transferred onto the paper P to the paper P by applying heat and pressure.

[0040] In the image forming unit 12, a toner image is primarily transferred onto a transfer belt 50 by a primary transfer roll 52 in the order of yellow (Y), magenta (M), cyan (C), and black (K). The toner image is then transferred from the transfer belt 50 by the secondary transfer roll 54 onto a sheet of paper P, which is conveyed while being sandwiched between the transfer belt 50 and the secondary transfer roll 54. The sheet of paper P onto which the toner image has been transferred is conveyed toward a fixing device 34. The fixing device 34 applies heat and pressure to the toner image transferred onto the sheet of paper P, thereby fixing the toner image to the sheet of paper P.

[0041] [Transport device 14] As shown in Fig. 1, the transport device 14 includes a feed roll 20, a prevention roll 22, an adjustment roll 24, and a discharge roll 26. The feed roll 20 has a function of sending out the paper P stored in the storage section 18 to the transport path 14a. The prevention roll 22 has a function of preventing double feeding of the paper P sent out by the feed roll 20. The adjustment roll 24 has a function of adjusting the timing at which the paper P is sent out to the transfer nip NT. The discharge roll 26 has a function of discharging the paper P to the outside of the device main body 10a.

[0042] [Paper discharge stacking device 80] As shown in FIG. 1, the discharged paper stacking device 80 is disposed above the transfer unit 32. The discharged paper stacking device 80 is a device that stacks the paper sheets P discharged from the discharge opening 78 by the discharge rolls 26. Details of the discharged paper stacking device 80 will be described later.

[0043] [Image reading unit 60] 1, the image reading unit 60 is disposed above the discharge roller 26. The image reading unit 60 includes a document transport unit 62 and a document reading unit 64. The document transport unit 62 and the document reading unit 64 are connected by a hinge unit 64a provided in the document reading unit 64.

[0044] The image reading unit 60 also includes a paper feed tray 66 and a discharge tray 68. The paper feed tray 66 is a tray that feeds a document placed on its top surface to the document transport unit 62. The discharge tray 68 is a tray on which the document S that has been read by the document reading unit 64 and discharged is placed. The paper feed tray 66 and the discharge tray 68 are attached to the document transport unit 62.

[0045] In the image reading unit 60, the document transport unit 62 is rotated around the hinge portion 64a, so that the upper surface (platen glass) of the document reading unit 64 is opened upward. Then, the document reading unit 64 reads an image of the document S placed on the platen glass (not shown) arranged on the upper surface of the document reading unit 64. The document reading unit 64 also reads an image of the document S transported by the document transport unit 62.

[0046] (Main part configuration) Next, the discharged paper stacking device 80 will be described in detail.

[0047] As shown in FIG. 1, the discharged paper stacking device 80 includes a tray 90 and a cushioning material 100 as an example of a shock absorbing portion.

[0048] -Tray 90- 1 and 3, the tray 90 is disposed below the discharge port 78 through which the paper P is discharged. As shown in FIGS. 8 and 9, the tray 90 has a function of stacking the paper P discharged from the discharge port 78 in a position in which the leading edge P1 of the paper P is positioned above the trailing edge P2 of the paper P. Specifically, the tray 90 includes a rear wall 92, a support portion 94, and a bottom portion 96.

[0049] As shown in FIGS. 3 and 4, the rear wall 92 is a wall portion below the discharge port 78 and extends in the vertical direction.

[0050] 8 and 9, the support portion 94 is a portion that supports the paper P discharged from the discharge opening 78. The support portion 94 is located forward of the rear wall 92 in the discharge direction of the paper P. Hereinafter, the discharge direction of the paper P will be referred to as the paper discharge direction. The paper discharge direction is indicated by an arrow E in each drawing.

[0051] The support section 94 gradually increases in height in the up-down direction toward the paper discharge direction. Specifically, as shown in FIG. 3, the support section 94 is inclined diagonally upward to the right when viewed from the front of the image forming apparatus 10. This inclination allows the support section 94 to load paper P in a position where the front end P1 is positioned higher than the rear end P2. Note that viewing the image forming apparatus 10 from the front refers to viewing it from one side in the device depth direction. Furthermore, the support section 94 may be inclined linearly diagonally upward to the right when viewed from the front of the image forming apparatus 10, or may be curved in an arc.

[0052] 3 and 6, the bottom portion 96 connects the rear wall 92 and the support portion 94. Specifically, the bottom portion 96 connects the lower end of the rear wall 92 and the lower end of the support portion 94. In this embodiment, the lower end of the support portion 94 is also the rear end in the paper discharge direction.

[0053] As shown in FIGS. 3 and 4 , the rear wall 92 includes a wall main body 93 and a pair of ribs 98. Each of the pair of ribs 98 protrudes from the wall main body 93 and extends downward. Specifically, each of the pair of ribs 98 is located below the discharge opening 78. Each of the pair of ribs 98 extends vertically to the bottom 96. Each of the pair of ribs 98 has a top surface 98A that protrudes from the surface 93A of the wall main body 93 by a constant amount toward the bottom 96. Specifically, the top surface 98A of each of the pair of ribs 98 is inclined obliquely downward toward the paper discharge direction, at an angle θ1 with respect to the vertical direction. Furthermore, the upper end 98B of each of the pair of ribs 98 is inclined at a larger angle with respect to the vertical direction than the top surface 98A. Note that the amount of protrusion of each of the pair of ribs 98 from the surface 93A toward the bottom 96 does not have to be constant.

[0054] In this embodiment, as an example, the interval between the pair of ribs 98 is constant in the up-down direction, but the present disclosure is not limited to this.

[0055] In this embodiment, as an example, the thickness of each of the pair of ribs 98 is constant in the up-down direction, but the present disclosure is not limited to this.

[0056] As shown in Fig. 6, a support surface 99 (see Fig. 7) is provided between the pair of ribs 98 to support the cushioning material 100 so that it is inclined diagonally downward toward the paper discharge direction when viewed from the side (depth direction of the device). Note that the side here refers to the left-right direction when the paper discharge direction is defined as the front-to-back direction. In other words, viewing from the side refers to viewing from the depth direction of the device.

[0057] As shown in FIG. 5, the pair of ribs 98 are provided on both sides of the wall main body 93 in the width direction across a center line CL that passes through the center of the outlet 78 in the width direction.

[0058] The tray 90 in this embodiment is configured as a part of the device main body 10a.

[0059] -Cushioning material 100- 3 and 4, the cushioning material 100 is provided on the rear wall 92. The cushioning material 100 has a function of receiving the rear end P2 of the paper sheets P loaded on the tray 90 and absorbing the impact caused by the collision of the paper sheets P.

[0060] As shown in FIG. 5, the cushion material 100 is provided at a distance from the rear wall 92 in the width direction of the discharge opening 78. Specifically, the cushion material 100 is disposed on both sides of the discharge opening 78 in the width direction. More specifically, the cushion material 100 is provided between a pair of ribs 98. As shown in FIG. 7, the cushion material 100 is supported by a support surface 99. The pair of ribs 98 is provided on both sides of the center line CL of the discharge opening 78 in the width direction. Therefore, the cushion material 100 provided between the pair of ribs 98 is also provided on both sides of the center line CL of the discharge opening 78 in the width direction (see FIG. 5).

[0061] The cushioning material 100 has a slope 102 that extends diagonally downward toward the paper discharge direction when viewed from the side (in the depth direction of the device). Specifically, as shown in FIGS. 6 and 7, the slope 102 extends diagonally downward to the right when viewed from the side (in the depth direction of the device) and intersects with the surface 92A of the rear wall 92. Note that the surface 92A of the rear wall 92 in this embodiment includes the surface 93A of the wall main body 93, the top surfaces 98A of the pair of ribs 98, and the support surface 99. In this embodiment, the slope 102 intersects with the top surfaces 98A of the pair of ribs 98 when viewed from the side (in the depth direction of the device). Note that in FIGS. 6 and 7, the point where the slope 102 and the top surface 98A intersect is indicated by the symbol C.

[0062] 9, the inclined surface 102 of the cushioning material 100 is inclined at an angle θ2 with respect to the vertical direction. Note that the angle θ2 is larger than the angle θ1. In FIG. 9, the angle between a line SL extending in the vertical direction and an extension of the inclined surface 102 is indicated as θ2, and the angle between the line SL and an extension of the top surface 98A is indicated as θ1.

[0063] When viewed from the side (in the depth direction of the device), the portion of the cushion material 100 below the intersection C protrudes further toward the paper discharge direction than the top surfaces 98A of the pair of ribs 98. Therefore, as shown in FIG. 9 , the trailing end P2 of the paper P contacts the top surfaces 98A of the pair of ribs 98 above the intersection C. The trailing end P2 of the paper P contacts the slopes 102 of the cushion material 100 below the intersection C. Here, the trailing end P2 of the paper P discharged from the discharge opening 78 may collide with the slopes 102 of the cushion material 100 and be stacked on the support section 94. The trailing end P2 of the paper P discharged from the discharge opening 78 may contact the top surfaces 98A of the pair of ribs 98, slide down along the top surfaces 98A to the slopes 102, and be stacked on the support section 94.

[0064] 7, the cushion material 100 is a sheet-like member. Specifically, the cushion material 100 is a sheet-like member with a constant thickness. Note that the present disclosure is not limited to this configuration, and the thickness of the cushion material 100 may vary to the extent of manufacturing error.

[0065] As shown in FIG. 7 , one side 100A of the cushion material 100 is attached to the rear wall 92. Specifically, the one side 100A is attached to the surface 92A of the rear wall 92 with adhesive tape. More specifically, the one side 100A is attached to the support surface 99 between a pair of ribs 98. The one side 100A of the cushion material 100 may be attached by applying an adhesive to the support surface 99. Alternatively, the one side 100A may be attached to the support surface 99 by applying an adhesive to the one side 100A. The one side 100A is one side of the sheet-like cushion material 100, and the opposite side is the slope 102.

[0066] (summary) As described above, in the discharged paper stacking device 80, as shown in FIG. 7, the trailing end P2 of the paper P discharged from the discharge port 78 collides with the inclined surface 102 of the cushion material 100. Colliding the trailing end P2 of the paper P with the inclined surface 102 of the cushion material 100 reduces the impact noise compared to when the paper P collides with the surface 72A of the rear wall 72. Also, as shown in FIG. 8, when the paper P is discharged, the trailing end P2 of the paper P moves smoothly from the surface 72A (top surface 98A) of the rear wall 72 to the inclined surface 102 of the cushion material 100. Therefore, in the discharged paper stacking device 80, stacking errors of the paper P can be reduced compared to a configuration in which the upper end of the cushion material 100 protrudes beyond the surface 92A of the rear wall 92 of the tray 90 when viewed from the side (in the depth direction of the device). Note that "stack errors" refers to variations in the paper stacking position caused by the trailing end P2 of the paper P getting caught on a corner of the cushion material 100.

[0067] 5, in the discharged paper stacking device 80, the cushion materials 100 are provided at intervals in the width direction of the discharge opening 78. Therefore, in the discharged paper stacking device 80, compared to a configuration in which only one cushion material 100 is provided on the rear wall 92, the cushion material 100 can receive the rear ends P2 of paper sheets P of two or more sizes.

[0068] 5, in the discharged paper stacking device 80, cushioning materials 100 are disposed on both widthwise sides of the discharge opening 78. Therefore, in the discharged paper stacking device 80, compared to a configuration in which cushioning materials 100 are provided only in the widthwise center of the discharge opening 78 on the rear wall 92, the cushioning materials 100 make it possible for the rear end P2 of the paper P discharged from the discharge opening 78 to be received on both widthwise sides of the discharge opening 78.

[0069] 4, in the discharged paper stacking device 80, the cushion material 100 is provided between a pair of ribs 98. Therefore, the cushion material 100 can be positioned by simply providing the cushion material 100 between the pair of ribs 98. In other words, in the discharged paper stacking device 80, the variation in the position of the cushion material 100 in the device depth direction can be reduced compared to a configuration in which the front surface 92A of the rear wall 92 is a flat surface and the cushion material 100 is provided on this flat surface.

[0070] 8, in the discharged paper stacking device 80, a support surface 99 is provided between a pair of ribs 98, which supports the cushion material 100 so that it is inclined obliquely downward toward the paper discharge direction when viewed from the side (in the direction toward the depth of the device). By placing the sheet-like cushion material 100 on this support surface 99, the surface of the cushion material 100 becomes an inclined surface 102. In this way, in the discharged paper stacking device 80, by providing the support surface 99 between the pair of ribs 98, a general-purpose sheet-like member can be used as the cushion material 100.

[0071] In the discharged paper stacking device 80, one side 100A of the cushion material 100 is attached to the surface 92A of the rear wall 92. Specifically, one side 100A of the cushion material 100 is attached to the support surface 99. Therefore, in the discharged paper stacking device 80, the cushion material 100 can be attached to the rear wall 92 more easily than in a configuration in which the cushion material 100 is attached to the rear wall 92 using a dedicated part.

[0072] (Other embodiments) In the above-described embodiment, as shown in Fig. 5, cushion materials 100 are arranged on both sides of the center line CL of the discharge outlet 78, but the present disclosure is not limited to this configuration. For example, as in the discharged paper stacking device 106 shown in Fig. 10, cushion materials 100 may be arranged on both sides of the center line CL of the discharge outlet 78, in addition to being arranged on the center line CL. In this case, a pair of cushion materials 100 can receive the trailing ends P2 of paper sheets P of two or more sizes. Note that cushion materials 100 may also be arranged only on the center line CL of the discharge outlet 78.

[0073] In the above-described embodiment, the cushion material 100 is used as an example of a shock absorbing portion, but the present disclosure is not limited to this configuration. For example, as in the paper output stacking device 108 shown in FIG. 11 , a cushion material 110 with a film 112 attached to its surface may be used as an example of a shock absorbing portion. Specifically, the cushion material 110 has a surface 110A attached to the support surface 99, and a film 112 with lower friction resistance than the cushion material 110 attached to the surface opposite the cushion material 110. By attaching the film 112 to the opposite surface of the cushion material 110 in this manner, the trailing end P2 of the paper P smoothly slides down on the film 112. Therefore, in the paper output stacking device 108, stacking failures of the paper P can be reduced compared to a configuration in which a film with the same or higher friction resistance as the cushion material 110 is attached. Note that in the configuration shown in FIG. 11 , the surface of the film 112 forms the slope of the shock absorbing portion.

[0074] In the above-described embodiment, a pair of ribs 98 is provided on the rear wall 92 of the tray 90. However, the present disclosure is not limited to this configuration. For example, as in the discharged paper stacking device 118 shown in FIGS. 12 and 13 , the rear wall 92 of the tray 90 may be provided with a storage recess 122 that stores at least the upper end of a cushion material 120. In the discharged paper stacking device 118, the rear wall 92 is provided with a support surface 124 that supports the cushion material 120 so that it slopes diagonally downward in the paper discharge direction from the storage recess 122 toward the bottom 96 of the tray 90 when viewed from the side (in the device depth direction). By placing the sheet-like cushion material 120 on this support surface 124, the surface of the cushion material 120 becomes an inclined surface 126. In this manner, in the discharged paper stacking device 118, by providing the support surface 99 on the rear wall 92, a general-purpose sheet-like material can be used as the cushion material 120.

[0075] Although the present disclosure has been described in detail with respect to specific embodiments, the present disclosure is not limited to such embodiments, and it will be apparent to those skilled in the art that various other embodiments are possible within the scope of the present disclosure.

[0076] (Addendum) (((1))) a tray that is disposed below a discharge port through which sheets are discharged and that stacks the sheets discharged from the discharge port in a position where the front ends of the sheets are positioned higher than the rear ends of the sheets; a shock absorbing section provided on a rear wall of the tray for receiving the rear ends of the sheets of paper loaded on the tray and absorbing shock caused by the sheets colliding with the tray, the shock absorbing section having a slope that extends obliquely downward in the sheet ejection direction as viewed from the side and intersects with the surface of the rear wall; A discharge stacking device comprising: (((2))) The discharged paper stacking device according to (((1))), wherein the shock absorbing portions are provided at intervals in the width direction of the discharge outlet. (((3))) The discharged paper stacking device according to (((1))) or (((2))), wherein the shock absorbing portions are arranged on both sides of the discharge opening in the width direction. (((4))) The discharged paper stacking device according to (((3))), wherein the shock absorbing portion is disposed on a center line in a width direction of the discharge outlet. (((5))) The rear wall includes a wall body and a pair of ribs that protrude from the wall body and extend downward, The shock absorbing portion is provided between the pair of ribs, The discharged paper stacking device according to (((1))), wherein the inclined surface intersects with the top surface of the rib included in the surface of the rear wall when viewed from the side. (((6))) the shock absorbing portion is a sheet-like member, The tray has a support surface between the pair of ribs that supports the shock absorbing portion so that it is inclined diagonally downward toward the discharge direction of the paper when viewed from the side. (((7))) the shock absorbing portion is a sheet-like member, The rear wall is provided with an accommodation recess that accommodates at least an upper end portion of the impact absorbing portion, The tray is provided with a support surface that supports the shock absorbing portion so that the shock absorbing portion is inclined obliquely downward in the paper discharge direction from the storage recess toward the bottom of the tray when viewed from the side. The discharged paper stacking device according to (((1))). (((8))) The shock absorbing portion is formed of a sheet-shaped cushion material, The discharged paper stacking device according to any one of (((1))) to (((7))), wherein one surface of the cushioning material is attached to the rear wall. (((9))) The discharged paper stacking device according to (((8))), wherein a film having a lower friction resistance than the cushion material is attached to a surface of the cushion material opposite to the rear wall. (((10))) an image forming unit that forms an image on a sheet; an outlet for discharging paper on which an image has been formed by the image forming unit; a discharged paper stacking device according to any one of (((1))) to (((9))) that stacks the paper discharged from the discharge port; An image forming system comprising:

[0077] The discharged paper stacking device (((1))) can reduce paper stacking errors compared to a configuration in which the upper end of the shock absorbing portion protrudes from the surface of the rear wall of the tray when viewed from the side. In the discharge stacking device of (((2))), the shock absorbing section can receive the trailing ends of two or more sizes of paper. In the discharged paper stacking device (((3))), the shock absorbing section makes it possible to receive the trailing edge of the paper discharged from the discharge opening on both sides in the width direction of the discharge opening. In the discharge stacking device of (((4))), the shock absorbing section can receive the trailing ends of two or more sizes of paper. In the discharge stacking device of (((5))), the variation in the position of the shock absorbing part in the width direction of the discharge outlet can be reduced compared to a configuration in which the surface of the rear wall is flat and the shock absorbing part is provided on the flat surface. In the discharged paper stacking device (((6))), a general-purpose sheet-like member can be used as the shock absorbing portion. In the discharged paper stacking device (((7))), a general-purpose sheet-like member can be used as the shock absorbing portion. In the discharged paper stacking device of (((8))), the cushioning material can be attached to the rear wall of the tray more easily than in a configuration in which the cushioning material is attached to the rear wall of the tray using a dedicated part. The discharged paper stacking device (((9))) can suppress improper paper stacking compared to a configuration in which a film with the same or higher friction resistance than the cushioning material is attached. In the image forming system (((10))), it is possible to prevent improper stacking of sheets discharged from the discharge port. [Explanation of symbols]

[0078] 10 Image forming device 12 Image forming unit 14 Conveyor equipment 26 Ejection Roll 10 Image forming device 10a Device body 12 Image forming unit 14 Conveyor equipment 14a Transport Route 18 Storage section 20 Sending Roll 22 Prevention Roll 24 Adjustment Roll 26 Ejection Roll 28 Control Unit 30 Toner image forming unit 32 Transcription unit 34 Fixing device 36 Image holder 42 Charger 44 Exposure equipment 46 Developing device 50 Transfer belt 52 Primary transfer roll 54 Secondary transfer roll 56 Winding Roll 58 Drive Roll 60 Image reading unit 62 Document transport section 64 Document reading unit 64a Hinge part 66 Paper feed stand 68 Discharge stand 78 Outlet 80 Paper discharge stacking device 90 trays 92 Back wall 92A surface 93 Wall body 93A surface 94 Support part 96 Bottom 98 Ribs 98A Top surface 98B Upper end 99 Support surface 100 cushioning material 100A single-sided 102 Slope 106 Paper discharge stacking device 108 Paper discharge stacking device 110 Cushioning material 112 Film 118 Paper discharge stacking device 120 cushioning material 122 Recessed storage area 124 Support surface 126 Slope θ1 angle θ2 angle C intersection CL center line G Developer NT Transfer Nip P paper P1 front end P2 rear end S manuscript H Device vertical direction D Depth of the device W Device width direction E Paper ejection direction

Claims

1. a tray that is disposed below a discharge port through which sheets are discharged and that stacks the sheets discharged from the discharge port in a position where the front ends of the sheets are positioned higher than the rear ends of the sheets; a shock absorbing section provided on a rear wall of the tray for receiving the rear ends of the sheets of paper loaded on the tray and absorbing shock caused by the sheets colliding with the tray, the shock absorbing section having a slope that extends obliquely downward in the sheet ejection direction as viewed from the side and intersects with the surface of the rear wall; A discharge stacking device comprising:

2. The discharged paper stacking device according to claim 1 , wherein the shock absorbing portions are provided at intervals in the width direction of the discharge opening.

3. The discharged paper stacking device according to claim 1 , wherein the shock absorbing portions are arranged on both sides of the discharge opening in a width direction.

4. The discharged paper stacking device according to claim 3 , wherein the shock absorbing portion is disposed on a center line in a width direction of the discharge opening.

5. The rear wall includes a wall body and a pair of ribs that protrude from the wall body and extend downward, The shock absorbing portion is provided between the pair of ribs, The discharged paper stacking device according to claim 1 , wherein the inclined surface intersects with the top surface of the rib included in the surface of the rear wall when viewed from the side.

6. the shock absorbing portion is a sheet-like member, The discharged paper stacking device according to claim 5 , wherein the tray is provided with a support surface between the pair of ribs that supports the shock absorbing portion so that the shock absorbing portion is inclined obliquely downward toward the discharge direction of the paper when viewed from the side.

7. the shock absorbing portion is a sheet-like member, The rear wall is provided with an accommodation recess that accommodates at least an upper end portion of the impact absorbing portion, The tray is provided with a support surface that supports the shock absorbing portion so that the shock absorbing portion is inclined obliquely downward in the paper discharge direction from the storage recess toward the bottom of the tray when viewed from the side. The discharged paper stacking device according to claim 1 .

8. The shock absorbing portion is formed of a sheet-shaped cushion material, The discharged paper stacking device according to claim 1 , wherein one surface of the cushioning material is attached to the rear wall.

9. 9. The discharged paper stacking device according to claim 8, wherein a film having a lower friction resistance than the cushion material is attached to a surface of the cushion material opposite to the rear wall.

10. an image forming unit that forms an image on a sheet; an outlet for discharging paper on which an image has been formed by the image forming unit; a discharged paper stacking device according to any one of claims 1 to 9, which stacks the paper discharged from the discharge port; An image forming system comprising:

Images