Paper output tray of an image forming apparatus and image forming apparatus
The tray design with a central protrusion and inclined surfaces corrects curling and maintains alignment of papers, addressing curling and alignment issues in image forming apparatuses.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- KONICA MINOLTA INC
- Filing Date
- 2022-07-05
- Publication Date
- 2026-06-23
AI Technical Summary
Existing paper discharge trays in image forming apparatuses face issues with curled and unstiffened paper curling on the tray and disrupting alignment during stacking.
The tray design features a first protrusion in the central part perpendicular to the discharge direction, with inclined first and second surfaces sloping downward, and recesses at both ends to support and guide the paper, correcting curling and maintaining alignment.
The design effectively suppresses curling and maintains aligned stacking of papers, even with varying curl directions, preventing misalignment and increasing stacking capacity.
Smart Images
Figure 0007877891000001 
Figure 0007877891000002 
Figure 0007877891000003
Abstract
Description
Technical Field
[0001] This invention relates to a paper discharge tray of an image forming apparatus for stacking printed paper discharged from the image forming apparatus and an image forming apparatus.
Background Art
[0002] As a paper discharge tray of an image forming apparatus, Patent Document 1 proposes providing a pair of convex members on the stacking surface of the paper discharge tray at symmetrically distributed positions on both the left and right sides in the conveyance direction centered on the center line in the paper conveyance direction and near the paper discharge roller. The convex members have inclined surfaces that gently descend toward the center line in the paper conveyance direction, and together with the stacking surface between the inclined surfaces, a gutter-shaped paper conveyance space is formed. In this paper discharge tray, it is said that when the tip of the paper bundle discharged by the paper discharge roller lands on the stacking surface, the landing point becomes higher and the landing angle becomes smaller. Also, the tip side of the paper bundle is slightly curved along the paper conveyance space, giving it stiffness, and thus it is very difficult to curl.
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0004] However, the paper discharge tray described in Patent Document 1 has a problem that when curled paper without stiffness is discharged, it curls on the paper discharge tray.
[0005] Also, when curled paper is discharged onto the tray, there is a problem that it is stacked in a disorderly manner without being aligned.
[0006] This invention was made to solve these problems, and aims to provide an output tray for an image forming apparatus and an image forming apparatus that can suppress problems such as paper that is not stiff and curled curls up on the output tray, and paper curling disrupting alignment during stacking. [Means for solving the problem]
[0007] The above objectives will be achieved by the following means. (1) A first protrusion is formed in the central part of the tray body in the direction perpendicular to the paper discharge direction, in the upstream region of the paper discharge direction. Furthermore, a first surface and a second surface following this first surface are formed on the downstream side of the first protrusion in the paper discharge direction. The first and second surfaces are inclined surfaces with a downward slope from the downstream side to the upstream side in the paper discharge direction. The inclination angle of the first surface is greater than the inclination angle of the second surface. A paper output tray for an image forming apparatus, characterized by the following features. (2) The output tray of the image forming apparatus according to paragraph 1, wherein the length of the tray body in the direction perpendicular to the paper output direction corresponds to the width of an A4 size sheet of paper, and the length of the first protrusion in the direction perpendicular to the paper output direction is 1 / 3 ± 10% of the length of the tray body in the direction perpendicular to the paper output direction. (3) A first protrusion is formed in the central part of the tray body in the upstream region in the paper discharge direction, in a direction perpendicular to the paper discharge direction, and a first surface and a second surface that follows the first surface and which the discharged paper first contacts are formed downstream of the first protrusion in the paper discharge direction. The first and second surfaces are inclined surfaces with a downward slope from the downstream side to the upstream side in the paper discharge direction. The output tray of an image forming apparatus is characterized in that the inclination angle of the first surface is greater than the inclination angle of the second surface, and the first surface is formed over the entire area in a direction perpendicular to the paper discharge direction of the tray body. (4) The first surface is located at the center of the maximum paper length of the tray body. One of 1-3 The output tray of the image forming apparatus described above. ( 5 ) Recesses are formed at both ends in the direction perpendicular to the paper discharge direction in the downstream region of the tray body in the paper discharge direction. The recess allows the center in the direction perpendicular to the paper discharge direction Having the second surface The second convex portion is formed in the preceding section 1~ 3 The output tray of the image forming apparatus described in any of the following. ( 6 ) Previous paragraph 1 ~3 An image forming apparatus equipped with a paper output tray as described in any of the following. [Effects of the Invention]
[0008] According to the invention described in paragraph (1) above, a first protrusion is formed in the central part of the upstream region of the tray body in the paper discharge direction, in a direction perpendicular to the paper discharge direction. Therefore, when paper that is not stiff is discharged to the output tray and stacked in a state where it is curled so that the central part in the paper discharge direction is the bottom, or where the central part in a direction perpendicular to the paper discharge direction is the bottom, the central part of the rear end of the paper in a direction perpendicular to the paper discharge direction is supported by the first protrusion, while both ends in the direction perpendicular to the paper discharge direction are subjected to a load in a direction that lowers below the upper surface of the first protrusion due to the weight of the stacked paper. In other words, because the paper conforms to the shape of the first protrusion, the curl of the rear end of the paper is corrected, and it is stacked in a aligned state. As a result, curling of the paper on the output tray can be suppressed, and disruption of alignment during stacking due to paper curl can be suppressed.
[0009] According to the invention described in item (2) above, the length of the tray body in the direction perpendicular to the paper discharge direction corresponds to the width of an A4 size sheet of paper, and the length of the first protrusion in the direction perpendicular to the paper discharge direction is 1 / 3 ± 10% of the length of the tray body in the direction perpendicular to the paper discharge direction, so the effect of (1) above can be reliably achieved.
[0010] According to the invention described in paragraph (3) above, a first protrusion is formed in the central part of the upstream region of the tray body in the paper discharge direction, in a direction perpendicular to the paper discharge direction, and a first surface and a second surface that follows the first surface and which the discharged paper first contacts are formed downstream of the first protrusion in the paper discharge direction, and the first surface and the second surface are inclined surfaces that slope downward from the downstream side to the upstream side in the paper discharge direction, the inclination angle of the first surface is greater than the inclination angle of the second surface, and the first surface is formed over the entire width of the tray body, so in addition to the effect of (1) above, it has the following effect.
[0011] In other words, the first sheet of paper that is ejected will initially have its leading edge come into contact with the second surface. However, since the inclination angle of the first surface is greater than that of the second surface, the ejected paper is prevented from coming into contact with the first surface, thus reducing the contact area between the paper and the output tray. Therefore, even if the paper is ejected far away during high-speed output, the ejected paper will slide down the inclined surface of the second surface and settle into the correct position, thus suppressing misalignment of the paper stacked on top of it.
[0012] Furthermore, even if the paper is curled upwards, when multiple sheets are stacked, their own weight will flatten the central part in the direction of paper discharge. However, since the first surface is formed over the entire area perpendicular to the paper discharge direction of the tray body, the flattened paper can be supported from below over the entire area perpendicular to the discharge direction, thereby suppressing misalignment of the stacked paper.
[0013] According to the invention described in paragraph (4) above, since the first surface is positioned at the center of the maximum paper length of the tray body, the function of the first surface can be effectively performed for various types of paper with different paper lengths.
[0014] According to the invention described in item (5) above, recesses are formed at both ends in the direction perpendicular to the paper discharge direction in the downstream region of the tray body in the paper discharge direction, and these recesses form a central part in the direction perpendicular to the paper discharge direction. Having a second sideSince the second convex portion is formed, even if curling occurs at the leading end side in the paper discharge direction, the paper follows the shape of the first convex portion, so the curling at the leading end portion of the paper is corrected and it is stacked in a state of being aligned. For this reason, it is possible to suppress the paper from curling on the paper discharge tray and to suppress the disturbance of alignment during stacking due to the curling of the paper.
[0016] According to the invention described in the preceding paragraph ( 6 ), it becomes an image forming apparatus that exhibits the effect of the paper discharge tray described in the preceding paragraph (1) ~ (3 )of any one of which is described).
Brief Explanation of Drawings
[0017] [Figure 1] It is a front view of the main part of an image forming apparatus provided with a paper discharge tray according to an embodiment of this invention. [Figure 2] It is a perspective view of the paper discharge tray. [Figure 3] It is a sectional view taken along line III-III of FIG. 2. [Figure 4] It is a perspective view of a paper discharge tray on which a curled paper without a waist is stacked. [Figure 5] It is a perspective view for explaining the function of the paper discharge tray when a paper whose central portion in the paper discharge direction is curled upward is discharged. [Figure 6] It is a perspective view for explaining the function of the paper discharge tray when a paper whose central portion in the paper discharge direction is curled downward is discharged. [Figure 7] It is a perspective view for explaining the function of the paper discharge tray when a paper whose central portion in a direction orthogonal to the paper discharge direction is curled upward is discharged. [Figure 8] It is a perspective view for explaining the function of the paper discharge tray when a paper whose central portion in a direction orthogonal to the paper discharge direction is curled downward is discharged.
Modes for Carrying Out the Invention
[0018] Hereinafter, embodiments of this invention will be described based on the drawings.
[0019] Figure 1 is a front view of the main part of an image forming apparatus equipped with a paper output tray 1 according to one embodiment of the present invention.
[0020] This image forming apparatus includes a paper output tray 1 for receiving and stacking paper P discharged from the paper output unit 2 in the direction of arrow A, and a scanner unit 3 for reading original documents located above the paper output tray 1.
[0021] Figure 2 is a perspective view of the paper output tray 1. The paper output tray 1 is provided with a connecting piece 18 at the upstream base end of the tray body 10 in the paper output direction (hereinafter also referred to as the length direction) for attaching the paper output tray 1 to the paper output section. The tray body 10 is also provided with a first protrusion 11 at the upstream end, and as shown in Figure 3, the tray body 10 is provided with a first recess 12 and a second recess 13 on both sides of the first protrusion in a direction perpendicular to the paper output direction (hereinafter also referred to as the width direction).
[0022] The first protrusion 11, the first recess 12, and the second recess 13 have a function to suppress curling when a curled, inflexible sheet of paper P is ejected, but this point will be described later.
[0023] In this embodiment, the width of the tray body 10 corresponds to the width of an A4 size sheet of paper, and the length L of the first protrusion 11 in the width direction of the tray body 10 (shown in Figure 3) is set to 1 / 3 ± 10% of the width of the tray body 10.
[0024] The reason the first recess 12 is deeper than the second recess 13 is to make it easier to insert a hand into the first recess 12 when removing paper that has been ejected into the output tray 1.
[0025] Downstream of the first protrusion 11 in the paper discharge direction, a first surface 14 is formed, continuous with the first protrusion 11, and downstream of this first surface 14, a second surface 15a is formed, continuous with the first surface 14.
[0026] The second surface 15a is formed in the downstream region of the tray body 10 in the longitudinal direction. This second surface 15a is the surface to which the leading edge of the paper P discharged from the paper discharge section 2 first contacts the paper output tray 1, and is formed as the upper surface of the second protrusion 15. It is also formed as an inclined surface with a downward slope from the downstream side of the tray body 10 in the longitudinal direction toward the first surface 14 on the upstream side.
[0027] The first surface 14 is formed over the entire width of the tray body 10 and is formed as an inclined surface with a downward slope from the portion connecting to the second surface 15a toward the portion connecting to the first protrusion 11. Moreover, the inclination angle of the first surface 14 is set to be greater than the inclination angle of the second surface 15a. The upper surface of the first protrusion 11 is also formed as an inclined surface with a downward slope from the portion connecting to the first surface 14 toward the base end of the tray body 10.
[0028] The reason why the first surface 14 is formed as an inclined surface with a larger inclination angle than the second surface 15a is as follows: When the first sheet of paper to be ejected, its leading edge first contacts the second surface 15a, and then the entire sheet is placed on the paper output tray 1, the first surface 14 is an inclined surface with a larger inclination angle than the second surface 15a, so the ejected paper does not come into contact with the first surface 14. As a result, the ejected paper moves more easily toward the base end of the paper output tray 1. In particular, when ejected at high speed, paper that has flown far downstream of the paper output tray 1 can be moved to the correct position, and the paper ejected afterward can be stacked in order, so that the paper can be stacked without misalignment.
[0029] The first surface 14 is positioned in the center of the maximum paper length that can be fed (for example, the length of A3 paper), ensuring that it can reliably load various types of paper with different lengths that are less than or equal to the maximum paper length without causing misalignment.
[0030] The second protrusion 15, having the second surface 15a on its upper surface, is formed in the center of the tray body 10 in the width direction, and a third recess 16 and a fourth recess 17 are formed on both sides of the center.
[0031] These second protrusions 15, third recesses 16, and fourth recesses 17 also function, as will be described later, to correct curling and suppress misalignment when curled, inflexible paper is stacked.
[0032] Next, as shown in Figure 4, the function of the output tray 1 for outputting and stacking paper P that is curled and lacks stiffness will be explained.
[0033] The manner in which curl occurs in paper P that lacks stiffness is not uniquely determined, and various types of curl occur. For example, as shown in Figure 5, paper P1 curls upward in the center along the length direction; as shown in Figure 6, paper P2 curls downward in the center along the length direction; as shown in Figure 7, paper P3 curls upward in the center along the width direction; and as shown in Figure 8, paper P4 curls downward in the center along the width direction.
[0034] First, let's explain the case where a sheet of paper P1 is ejected with its lengthwise central portion curled upwards, as shown in Figure 5. In this curled state, both ends of the paper in the width direction on the leading edge side tend to catch on the stacked paper and curl up during ejection.
[0035] In the output tray 1 according to this embodiment, the first sheet of paper P1 to be output first has its leading edge contact with the second surface 15a, and then the entire sheet is placed on the output tray 1. At this time, since the first surface 14 is an inclined surface with a greater inclination angle than the second surface 15a, the output paper P1 does not come into contact with the first surface 14. As a result, the output paper P1 moves more easily toward the upstream side of the output tray 1. In particular, when paper is output at high speed, paper P1 that has flown far to the downstream side of the output tray 1 can be moved upstream to the correct position, and subsequent output paper P1 can be stacked sequentially, so that the paper can be stacked without misalignment.
[0036] When multiple sheets of paper P1 are stacked, the paper P1 is subjected to a downward load due to the stacked weight. However, since the first surface 14 is formed over the entire width of the tray body 10, the entire width of the paper P1 is supported by the connecting portion of the first surface 14 and the second surface 15a. Furthermore, the widthwise center of the leading and trailing ends of the paper P1 is supported by the first and second protrusions 11 and 15, respectively, and conforms to the shape of these protrusions. As a result, the curl of the entire paper is corrected.
[0037] Furthermore, both ends of the paper P1 in the width direction at the leading and trailing ends receive a downward load indicated by arrow B in Figure 5, causing them to sink into the first recesses 12 and 2 recesses 13 on both sides of the first protrusion 11, and also into the third recesses 16 and 4 recesses 17 on both sides of the second protrusion 15. As a result, the central leading end of the ejected paper P1 makes contact with the stacked paper first, with contact at both ends delayed, making it less likely for the paper P1 to curl. Also, the central trailing end of the paper P1 makes contact before the ends, preventing the ends from getting caught on the stacked paper P1 and curling.
[0038] Next, we will explain the case where a sheet of paper P2 is discharged with its longitudinal center curled downwards, as shown in Figure 6. In this curled state, when the sheet of paper P2 is stacked, the height of the curled ends of the sheet of paper P2 increases, which can limit the stacking capacity, block the paper output opening of the paper output unit 2, or cause the leading edge of the sheet of paper P2 to lift up and come into contact with the scanner unit 3.
[0039] In the paper output tray 1 according to this embodiment, the paper P2 is subjected to a downward load due to the weight of the stack, but since the first surface 14 is formed over the entire width of the tray body 10, the entire width of the paper P2 is supported by the connecting portion of the first surface 14 and the second surface 15a. Furthermore, the widthwise center of the leading and trailing ends of the paper P2 is supported by the first protrusion 11 and the second protrusion 15, and conforms to the shape of these protrusions. As a result, the overall curl of the paper P2 is corrected.
[0040] Furthermore, both ends of the paper P2 in the width direction at the leading and trailing ends are subjected to a downward load as indicated by arrow B in Figure 5, causing them to sink into the first recesses 12 and 2 recesses 13 on both sides of the first protrusion 11, and further into the third recesses 16 and 4 recesses 17 on both sides of the second protrusion 15, thereby further correcting the curl.
[0041] Because the curl is corrected in this way, the height of the curled portion at the leading and trailing edges of the paper P2 does not increase, which can prevent problems such as limited stacking capacity, blocking the paper output slot, or the leading edge of the paper lifting up and coming into contact with the scanner unit 3.
[0042] Next, we will explain the case where paper P3 is ejected with its central part in the width direction curled upwards, as shown in Figure 7.
[0043] The first sheet of paper P3 is initially placed on the output tray 1 after its leading edge first contacts the second surface 15a. At this time, since the first surface 14 has a steeper inclination angle than the second surface 15a, the ejected paper P3 does not come into contact with the first surface 14. As a result, the ejected paper P3 moves more easily towards the upstream side of the output tray 1. In particular, when the paper P3 is ejected at high speed, the paper P3 that flies far downstream of the output tray 1 moves to the correct position, and the subsequently ejected paper P3 is stacked sequentially, allowing for stacking without alignment problems.
[0044] When multiple sheets of paper are stacked, the paper P3 is subjected to a downward load due to the stacked weight. However, since the first surface 14 is formed over the entire width of the tray body 10, the entire width of the paper P3 is supported by the connecting portion of the first surface 14 and the second surface 15a. Furthermore, the widthwise center of the leading and trailing ends of the paper P3 is supported by the first and second protrusions 11 and 15, respectively, and conforms to the shape of these protrusions. As a result, the curl of the entire paper is corrected.
[0045] Furthermore, since the front and rear ends of the P3 paper are naturally curled downwards in the width direction, they naturally sink into the first recess 12 to the fourth recess 17. As a result, the stacking height does not increase, and the leading edge of the ejected P3 paper does not get caught on the stacked P3 paper, preventing it from curling.
[0046] Next, we will explain the case where a sheet of paper P4 is discharged with its central part in the width direction curled downwards, as shown in Figure 8. In this curled state, when the sheet of paper P4 is stacked, the height of the curled portion at the front and rear ends of the sheet of paper P4 increases, which can limit the stacking capacity, block the paper output opening of the paper output unit 2, or cause the leading edge of the sheet of paper P4 to lift up and come into contact with the scanner unit 3.
[0047] In the paper output tray 1 according to this embodiment, the paper P4 is subjected to a downward load due to the weight of the stack, but since the first surface 14 is formed over the entire width of the tray body 10, the entire width of the paper P4 is supported by the connecting portion of the first surface 14 and the second surface 15a. Furthermore, the widthwise center of the leading and trailing ends of the paper P4 is supported by the first and second protrusions 12 and 15, and conforms to the shape of these protrusions. As a result, the curl of the entire paper is corrected.
[0048] Furthermore, both ends of the width direction at the leading and trailing ends of the paper P4 are subjected to a downward load as indicated by arrow B in Figure 5, causing them to sink into the first recesses 12 and 2 recesses 13 on both sides of the first protrusion 11, and further into the third recesses 16 and 4 recesses 17 on both sides of the second protrusion 15, thereby further correcting the curl.
[0049] Because the curl is corrected in this way, the height of the curled portion at the leading and trailing edges of the P4 paper does not increase, which can prevent problems such as limited stacking capacity, blocking the paper output slot, or the leading edge of the P4 paper lifting up and coming into contact with the scanner unit 3.
[0050] Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment. For example, although a paper output tray 1 has been described which is provided with a first convex portion 11, first and second recesses 12 and 13, a first surface 14, a second convex portion 15, and third and fourth recesses 16 and 17, it may also be provided with only the first convex portion 11 and first and second recesses 12 and 13, or with only the first convex portion 11, first and second recesses 12 and 13 and the first surface 14, or with only the second convex portion 15 and third and fourth recesses 16 and 17. [Explanation of symbols]
[0051] 1 Paper feed tray 2 Paper output section 3. Scanner section 10 Tray body 11 First convex part 12 First recess 13. Second recess 14. The first side 15. Second convex part 15a Second surface 16 Third recess 17. The fourth recess 18 Connecting piece P, P1~P4 paper
Claims
1. A first protrusion is formed in the central part of the tray body in the upstream region in the paper discharge direction, in a direction perpendicular to the paper discharge direction, and a first surface and a second surface following the first surface are formed on the downstream side of the first protrusion in the paper discharge direction. The first and second surfaces are inclined surfaces with a downward slope from the downstream side to the upstream side in the paper discharge direction. The output tray of an image forming apparatus, characterized in that the inclination angle of the first surface is greater than the inclination angle of the second surface.
2. The output tray of an image forming apparatus according to claim 1, wherein the length of the tray body in the direction perpendicular to the paper discharge direction corresponds to the width of an A4 size sheet of paper, and the length of the first protrusion in the direction perpendicular to the paper discharge direction is 1 / 3 ± 10% of the length of the tray body in the direction perpendicular to the paper discharge direction.
3. A first protrusion is formed in the central part of the tray body in the upstream region in the paper discharge direction, in a direction perpendicular to the paper discharge direction, and a first surface and a second surface that follows the first surface and which the discharged paper first contacts are formed downstream of the first protrusion in the paper discharge direction. The first and second surfaces are inclined surfaces with a downward slope from the downstream side to the upstream side in the paper discharge direction. The output tray of an image forming apparatus is characterized in that the inclination angle of the first surface is greater than the inclination angle of the second surface, and the first surface is formed over the entire area in a direction perpendicular to the paper discharge direction of the tray body.
4. The output tray of an image forming apparatus according to any one of claims 1 to 3, wherein the first surface is positioned at the center of the maximum paper length of the tray body.
5. Recesses are formed at both ends of the tray body in the region downstream of the paper discharge direction, in a direction perpendicular to the paper discharge direction. The output tray of an image forming apparatus according to any one of claims 1 to 3, wherein the recess forms a second convex portion having the second surface in the center of a direction perpendicular to the paper output direction.
6. An image forming apparatus comprising a paper output tray according to any one of claims 1 to 3.