JP3621997B2 - Output tray of image forming device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an improvement of a paper discharge tray used in an image forming apparatus such as a copying machine, a printer, a facsimile machine, and a printing apparatus, and in particular, a sheet discharged from the paper discharge port of the apparatus to the outside of the machine is deformed on the tray, The present invention relates to a paper discharge tray that can eliminate problems such as slipping off.
[0002]
[Prior art]
In the conventional image forming apparatus, as shown in FIG. 3, the pickup roller 18 takes out the paper 4 stored in the paper feed tray 17 and conveys it to the registration roller 20 by the conveyance roller 19. The sheet is fed by the registration roller 20 between the transfer charger 22 and the photosensitive drum 21 at a timing synchronized with the toner image formed on the surface of the photosensitive drum 21 rotating in the direction of the arrow. The toner image on the photosensitive drum 21 is transferred to the paper 4 by the discharge. The transferred paper 4 is further separated from the photosensitive drum 21 by the separation charger 23, conveyed to the fixing unit 2 by the conveyance unit 24, and fixed. The sheet 4 on which the toner image is copied is discharged by a discharge roller 6 and a driven roller (discharge roller) 7 and is stacked on the discharge tray 1.
[0003]
[Problems to be solved by the invention]
However, the conventional paper discharge tray 1 is attached below the nip position between the paper discharge roller 6 and the driven roller 7 in order to secure a storage space for the discharged paper 4, and further the paper on the paper discharge tray 1. In order to align the four alignment states, the front end of the paper discharge tray 1 is inclined upward. Therefore, the low-stiff paper 4 such as the second original drawing paper, the film paper, or the thin paper is easily crooked while the paper discharge tray 1 is stacked, as shown in FIG. As a result, the sheet 4 is deformed, and the next sheet is undesirably blocked by the preceding sheet, causing jamming at the sheet discharge port.
Also, weak paper such as second original paper, film paper, and thin paper is easily curled at both ends in the width direction as a result of being heated in the fixing unit 2, and as shown in FIG. Both ends of the sheet 4 in the width direction can easily block the sheet discharge outlet. Then, the next paper collided with the curled portion of the preceding paper and the paper 4 already stacked on the paper discharge tray 1 was pushed out and dropped from the paper discharge tray 1.
According to the first aspect of the present invention, the low-stiffness paper such as the second original paper, the film paper, or the thin paper is prevented from buckling and deforming on the paper discharge tray. Even when a large upward curl is generated at both ends in the width direction due to heating in the fixing unit, it can be neatly stacked on the discharge tray without hindering subsequent discharge of the paper, and the discharged paper can be discharged. The purpose is to prevent falling from the tray.
Also, since the second original drawing paper and film paper are easily charged with static electricity, the paper 4 already stacked on the paper discharge tray 1 is pushed out as shown in FIG. It is easy to cause. For this reason, static electricity is removed by providing a static elimination brush 10 at the paper discharge port and contacting the paper. However, the malfunction shown in FIG. 6 is caused by static electricity remaining on the paper after passing through the static elimination brush. Is still occurring.
According to the second aspect of the present invention, even when a sheet that is easily charged with static electricity, such as a second original drawing paper or a film paper, is discharged, discharge that can prevent the occurrence of misalignment due to electrostatic adsorption. The purpose is to provide a tray.
In JP-A-64-64966 (Matsushita Electric Industrial Co., Ltd.), a sheet discharged by a claw roller having a claw on the outer periphery that rotates in the same direction in synchronization with the second discharge roller is disclosed. Although a technique has been disclosed in which paper discharged is arranged in an orderly manner on a paper discharge tray, the above-described problems cannot be solved by this conventional example.
[0004]
[Means for Solving the Problems]
In order to achieve the above object, a first aspect of the present invention is a discharge tray disposed outside a pair of discharge rollers positioned at a discharge outlet of an image forming apparatus. includes a tray main body mounted obliquely upward to the outer wall of the lower outward, and a rotating tray piece that is rotatably supported in the vertical direction by the tray main body, the the pivoting tray piece, discharging A wide portion located on the downstream side in the paper direction and a narrow portion located on the upstream side in the paper discharge direction from the wide portion, and the narrow portion is substantially the same height as the nip portion of the paper discharge roller pair. It is possible to rotate between a first posture and a second posture in which the narrow width portion is lower than the nip portion of the paper discharge roller pair and is substantially the same height as the tray body (no or few steps). When held in the first posture, the sagging portions are on both sides in the width direction of the narrow portion. Characterized in that it is made.
According to a second aspect of the present invention, in the first aspect, a fence member that advances and retreats along the paper discharge direction is provided on the upper surface of the rotating tray piece, and the fence member is positioned according to the length of the paper to be discharged. It is characterized by doing so.
An image forming apparatus according to a third aspect of the present invention includes the paper discharge tray according to the first or second aspect.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings. In addition, with reference also to FIG. 3, the same code | symbol is attached | subjected to the same part. FIG. 1A is a perspective view of a paper discharge tray according to an embodiment of the present invention, and FIGS. 1B and 1C are front views thereof. The paper discharge tray 1 has a configuration inclined obliquely upward like the paper discharge tray shown in FIG. 3, and is a non-movable tray main body 100 attached to the lower outer wall of the paper discharge port of the image forming apparatus. The middle portion of the tray body 100 is vertically positioned by a notch 101 formed by notching the central portion of the front edge of the tray body 100 into a concave shape and a shaft 103 provided at each of the two end portions 102 of the front end of the tray body 100. And a rotating tray piece 104 having a convex shape that is rotatably supported and is aligned in the notch 101.
The rotating tray piece 104 protrudes upstream from the central part of the upstream end of the wide part and the wide part 104a located on the front side (downstream side in the paper discharge direction) and the rear part (upstream side in the paper discharge direction) . ) And the rotating tray piece 104 is in a posture parallel to the tray body 100 shown in FIG. 1B, and the rotating tray piece shown in FIG. The nip portions of the roller pairs 6 and 7 and the upper surface of the rotating tray piece are in the same level). The rotating tray piece 104 may be rotated by a driving source such as a motor or a solenoid (not shown) according to the type of paper to be used, or may be rotated manually.
In other words, the rotating tray piece 104 has a wide width portion 104a located on the downstream side in the paper discharge direction and a narrow width portion 104b located on the upstream side in the paper discharge direction from the wide width portion 104a. The first posture (FIG. 1 (c)) in which 104b is almost the same height as the nip portion of the discharge roller pair 6 and 7, and the narrow width portion 104b is lower than the nip portion of the discharge roller pair 6 and 7, It is held so as to be rotatable between a second posture (FIG. 1 (b)) that is substantially the same height as the main body 100 (with or without a level difference), and the narrow width when held in the first posture. 104 A of depression parts are formed in the width direction both sides of a part .
[0006]
According to the discharge tray 1 of this embodiment, as shown in FIG. 1A, the rotating tray piece 104 is rotated so that the rear end edge of the narrow width portion 104b is brought into contact with the nip of the discharge rollers 6 and 7. In this state, as shown in the drawing, the sheet 4 discharged onto the rotating tray piece 104 has a notch (a depressed portion) formed at both ends in the width direction by the wide width portion 104a and the narrow width portion 104b. ) Since it falls into 104A due to its own weight, even if both ends in the width direction are curled upward as shown in FIG. 5, both ends in the width direction are notched 104A. It will fall into the interior, so that it will not interfere with the paper exit and will not interfere with the subsequent ejection of the paper and will not push out the paper that has already been ejected.
In addition, instead of notching the both sides in the width direction of the rear portion of the rotating tray piece over a predetermined area to form the notch 104A, a portion corresponding to the notch 104A is defined as a recess (a portion having a lower predetermined length = a depressed portion). Can achieve the same effect.
In addition, when the upper surface of the rotating tray piece 104 is set in a horizontal posture with the nip portion of the paper discharge rollers 6 and 7 as shown in FIG. 1C, the occurrence of buckling as shown in FIG. 4 is effectively prevented. can do.
[0007]
Next, FIG. 2 is a front view of another embodiment of the present invention. The sheet discharge tray of this embodiment is a fence member 110 that can be advanced and retracted in the sheet discharge direction on the upper surface of the rotating tray piece 104 shown in FIG. Therefore, by determining the position of the fence member 110 according to the length of the paper 4 in the discharge direction, the leading edge of the paper discharged by the fence member can be securely pressed, and friction between the paper 4 and static electricity It is possible to prevent the already stacked sheets from being pushed forward by the suction force of the. This fence member can be applied not only to a paper discharge tray having a rotating tray piece having the shape shown in FIG. 1 but also to a paper discharge tray having various shapes of rotating tray pieces.
Note that by using the paper discharge tray 1 of the present invention as the paper discharge tray 1 of the image forming apparatus shown in FIG. 3, an image forming apparatus that eliminates stacking defects on the paper discharge tray can be obtained. .
[0008]
【The invention's effect】
As described above, according to the discharge tray of the first aspect, the discharge tray is configured by the non-movable tray body and the rotating tray piece supported by the tray body so as to be movable up and down. Since the rear side is a narrow part, both ends in the width direction of the stacked paper can be lowered downward by an amount narrower than that of the wide part (by a notch or a recess). Even if upward curling occurs at both ends in the width direction of the sheet, the curling unit does not prevent the subsequent sheet from being discharged, and the sheet can be loaded reliably.
In addition, if the rotating tray piece is locked at the rotated position and the upper surface of the rotating tray piece is placed on the extension of the nip position of the pair of discharge rollers, the discharged paper is discharged to the upper surface of the tray with no step (less). Therefore, even a sheet with low stiffness can be reliably stacked on the paper discharge tray without causing buckling.
In the paper discharge tray according to claim 2, since the fence member that advances and retreats in the discharge direction is provided on the stacking surface of the rotating tray piece so as to press the leading edge of the discharged paper, Misalignment can be prevented.
[Brief description of the drawings]
1A is a perspective view of a paper discharge tray according to an embodiment of the present invention, and FIG. 1B is a front view thereof.
FIG. 2 is a front view showing the configuration of another embodiment of the present invention.
FIG. 3 is a front longitudinal sectional view of a conventional image forming apparatus to which the present invention is applied.
FIG. 4 is a diagram illustrating a defect of a conventional paper discharge tray.
FIG. 5 is a view showing another defect of a conventional paper discharge tray.
FIG. 6 is a view showing another defect of a conventional paper discharge tray.
[Explanation of symbols]
1 discharge tray, 4 sheets, 6 discharge roller, 7 driven roller, 100 tray body, 101 notch, 102 end, 103 shaft, 104 rotating tray piece, 104a wide width portion, 104b narrow width portion, 104A notch (Depressed part).

Claims (3)

In the paper discharge tray disposed outside the pair of paper discharge rollers positioned at the paper discharge port of the image forming apparatus, the paper discharge tray is attached obliquely upward toward the outside on the outer wall below the paper discharge port. A tray body, and a rotating tray piece supported by the tray body so as to be rotatable in the vertical direction. The rotating tray piece has a wide width portion located on the downstream side in the paper discharge direction, and the wide width portion. A first posture in which the narrow width portion is located on the upstream side in the paper discharge direction, and the narrow width portion is substantially the same height as the nip portion of the paper discharge roller pair, and the narrow width portion is the paper discharge It is lower than the nip portion of the roller pair, and is held so as to be rotatable between a second posture which is substantially the same height as the tray body, and when held in the first posture, both sides in the width direction of the narrow portion. A discharge tray of an image forming apparatus , wherein a depression portion is formed on the sheet. 2. A fence member which advances and retreats along the paper discharge direction is provided on the upper surface of the rotating tray piece, and the fence member is positioned according to the length of paper to be discharged. Discharge tray of the image forming apparatus. An image forming apparatus comprising the paper discharge tray according to claim 1.

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