JP2001089005A - Paper stacking device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stack post-processed paper in well balance, and to prevent the paper from falling down from a tray. SOLUTION: A paper stacking device 50 stacking/storing paper fed out from a post-processing device united to an image forming device, comprises; stacking trays 52, 54, 56, 58 divided into plural parts; eccentric cams 60, 62, 64, 66 and motors 68, 70, 72, 74 respectively move the divided stacking trays 52, 54, 56, 58 independently in a vertical direction; and a control portion 76 controlling the stacking trays 52, 54, 56, 58 to selectively move according to a pint mode established by an image forming device or the post-processing device, or an outer device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet stacking apparatus for stacking sheets discharged from a post-processing apparatus connected to an image forming apparatus.

[0002]

2. Description of the Related Art Conventionally, a sheet stacking apparatus for stacking sheets discharged from a post-processing apparatus generally stacks sheets on an integrated stacking tray.

[0003]

However, in the conventional paper stacking apparatus, the post-processed portions are overlapped as the paper or the bundle of sheets subjected to post-processing such as paper folding or stapling is stacked. There has been a problem that the stacking height is higher than other portions, so that the stacking state becomes oblique, and the sheet or sheet bundle may drop from the stacking tray.

[0004]

In order to solve the above-mentioned problems, a first invention is a sheet stacking device for stacking and storing sheets discharged from a post-processing device connected to an image forming apparatus, A stacking tray divided into a plurality of sheets in the sheet discharge direction, a driving unit for vertically moving each of the divided stacking trays independently, and a print mode set by the image forming apparatus or the post-processing apparatus or an external apparatus. Control means for controlling the stacking tray to be selectively moved.

[0005] In the sheet stacking device of the first invention, the control means may adjust the descending amount of the stack tray in accordance with the number of sheets to be discharged.

In the paper stacking apparatus of the first invention, the print mode includes a print mode including a paper folding process, a print mode including a stapling process, and a print mode including continuous jobs having different paper sizes.

According to a second aspect of the present invention, there is provided a sheet stacking apparatus, wherein a stacking tray for stacking and storing sheets discharged from a post-processing apparatus connected to an image forming apparatus is adjacent to the stacking tray in a direction orthogonal to the sheet discharging direction. And a paper fall prevention member arranged in a vertical direction.

In the sheet stacking apparatus according to a second aspect of the present invention, the stacking tray is divided into a plurality of sheets in a sheet discharging direction, and the stacking tray is divided according to a print mode set by the image forming apparatus, the post-processing apparatus, or an external device. Each loading tray may be selectively movable up and down.

In the paper stacking apparatus according to the second aspect of the present invention, the paper fall prevention member is movable back and forth with respect to the stacking tray, and advances to a position adjacent to the stacking tray at least during stacking of the paper. You may make it.

[0010]

In the paper stacking apparatus according to the first aspect of the present invention, the control means, depending on the print mode, determines whether one of the paper-stacked and post-processed portions, such as paper folding and staple, overlaps when the paper is stacked. Alternatively, the height of a plurality of loading trays is made lower than the other loading trays. As a result, it is possible to prevent the stacking height of the stacked sheets where the post-processing portion overlaps from protruding and increasing. As a result, the stacking balance of the sheets is improved, and the stacked sheets can be prevented from collapsing or falling from the tray.

In the paper stacking apparatus according to the second aspect of the present invention, since the paper fall prevention member is provided adjacent to the stack tray, the stacked paper can be more reliably prevented from falling from the tray.

[0012]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 shows an image forming apparatus 10 and a post-processing apparatus 20 connected thereto. An image forming apparatus 10 such as a copying machine or a printer includes a discharge unit 12 for discharging a sheet on which an image is formed out of the apparatus.
It has. In addition, an operation panel (not shown) for setting a print mode including post-processing contents such as folding and stapling is provided at an upper portion of the image forming apparatus 10.
The print mode may be set by an external device (not shown) such as a personal computer connected to the image forming apparatus 10, and the post-processing content of the print mode is provided in the post-processing apparatus 20. Alternatively, the setting may be made on an operation panel (not shown).

The post-processing device 20 includes a carry-in unit 22 for carrying the paper discharged from the discharge unit 12 of the image forming apparatus 10, and a first for feeding the carried-in paper to the paper folding unit 24 in the paper folding mode. The switching direction of the sheet that has passed through the first switching claw 26 via the switching claw 26 or the paper folding unit 24 or not via the paper folding unit 24 is switched to either the first transportation path 28 or the second transportation path 30. 2 switching claw 32, first transport path 28
Tray section 3 for storing paper conveyed through the
4. a stapling section 36 for performing stapling processing on a bundle of sheets stacked and aligned in the storage tray section 34, and the second transport path 3
0, or a discharge unit 40 that discharges a sheet bundle that has been conveyed through the third conveyance path 38 after being stapled, and a sheet that discharges or discharges the sheet bundle from the discharge unit 40. A loading device 50 is provided.

As shown in FIG. 2, the paper stacking device 50 includes
The stacking trays 52, 5 divided into four in the sheet discharging direction (the direction of arrow A) from the discharging unit 40 composed of a roller pair
4, 56, 58. The stacking trays 52 are arranged in a horizontal state, and the stacking trays 54, 56, and 58 are arranged obliquely with respect to the horizontal direction in a plane-matching state. Each of the stacking trays 52, 54, 56, 58 is supported by its lower surface abutting on a disk-shaped or roller-shaped eccentric cam 60, 62, 64, 66, respectively. Each eccentric cam 60, 6
The motors 2, 64, 66 are driven to rotate by motors 68, 70, 72, 74, respectively, connected via gears (not shown). When each of the eccentric cams 60, 62, 64, and 66 is rotated by driving the motors 68, 70, 72, and 74, the loading tray 52 is moved in the vertical direction.
Reference numerals 56 and 58 are configured to independently move up and down in directions inclined from the vertical direction. In addition, each motor 6
8, 70, 72, 74 are electrically connected to the control unit 76, respectively. The control unit 76 drives the motors 68, 70, 72, 74 in accordance with the set print mode, thereby selectively moving the stacking trays 52, 54, 56, 58 up and down. . The control unit 76 also controls the eccentric cam 6 according to the number of sheets to be discharged.
By changing the rotation amounts of 0, 62, 64 and 66, the descending amounts of the stacking trays 52, 54, 56 and 58 can be adjusted respectively.

It is needless to say that the number of divisions of the stacking tray may be other than four. Also, the loading trays 52, 5
The drive means of 4, 56 and 58 is not limited to the eccentric cam, but may be another mechanism (for example, a link mechanism or a solenoid).

The sheet stacking device 50 also has a plate-shaped sheet falling prevention member 78 below the discharge section 40. The sheet drop prevention member 78 is operated by a drive mechanism (not shown).
It can move back and forth between a retracted position shown by a solid line and an operating position shown by a two-dot chain line. When in the operating position, the sheet falling prevention member 78 is disposed adjacent to the stacking tray 52 in a direction orthogonal to the sheet discharging direction (the direction of arrow A).

The sheet falling prevention member 78 is preferably a plate-like member, but may be formed of a rod-like member. Further, the sheet drop prevention members 78 are preferably arranged on both sides of the stacking tray 52. However, if the direction in which the stacked sheets easily collapse and fall is determined in one direction, they are arranged only in that direction. It should just be.

Next, the post-processing apparatus 2 having the above configuration
0, in particular, the operation of the paper stacking device 50 will be described.
Also, a case will be described here where the print mode includes a process of folding a sheet into a substantially Z shape in three.

The sheet discharged from the discharge section 12 of the image forming apparatus 10 is carried into the post-processing apparatus 20 from the carry-in section 22 and sent to the sheet folding section 24 by the switching claw 26. Therefore, the sheet is folded into three substantially in a Z shape and
Sent out from. Then, the sheet is discharged from the discharge unit 40 to the sheet stacking device 50 via the second transport path 30.

As shown in FIG. 3, when the sheet P is discharged from the discharge unit 40 onto the stacking trays 52, 54, 56, and 58, the stacking tray 52 corresponding to the position where the sheet folding unit overlaps the control unit. 76, the distance is lowered by a predetermined distance corresponding to the number of discharged sheets. At this time, the sheet fall prevention member 78 has advanced to the operating position indicated by the solid line. In this state, when the sheets P are stacked and stored, the stacking height of the folded portion of the stacked sheets P is higher than that of the other portions because the stacking tray 52 is lowered. It is possible to suppress the protrusion from becoming high. As a result, the loading balance of the paper P is improved, and the loaded paper P
Can be prevented from collapsing and falling from the tray.
Further, the sheet P from the tray can be more reliably prevented from falling by the sheet falling prevention member 78 at the operating position.

Next, the paper stacking operation when the print mode includes continuous jobs of different paper sizes will be described. As shown in FIG. 4, in the first job, a predetermined number of small-sized sheets P1 are stacked on the stacking trays 52 and 54. Thereafter, when the large-size paper P2 is loaded in the next job, the loading trays 52 and 54 on which the small-size paper P1 is loaded are lowered. As a result, the upper surface of the uppermost small-sized paper P1 is positioned substantially at the same level as the stacking trays 56 and 58, and the large-sized paper P2 can be stacked thereon in a balanced manner. As a result, it is possible to prevent the large-sized paper P2 to be stacked from being collapsed and falling from the tray. Also, the sheet fall prevention member 78 at the operating position can more reliably prevent the sheet from falling from the tray.

In the above-described example, the case where the print mode includes a paper folding process or a continuous job with a different paper size has been described. However, even in the case where the print mode includes the stapling process, the position where the staple portions of the sheet bundle overlap each other is described. Is lowered and the sheet fall prevention member 78 is advanced to the operating position, so that the stapled sheet bundle is stacked on the stacking trays 52, 54, and 5.
6, 58 can be stacked in a well-balanced manner, and a bundle of sheets can be prevented from falling from the tray.

It is sufficient that the sheet fall prevention member 78 is at least in the operating position during the stacking of the sheets. It may be fixedly provided. Further, the sheet fall prevention member 78 is not only effective for a divided stacking tray, but can also exhibit a sheet fall prevention function by being applied to an undivided stacking tray.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a post-processing device connected to an image forming apparatus.

FIG. 2 is a side view of a sheet stacking device of the post-processing device.

FIG. 3 is a side view showing an operation state of the sheet stacking device.

FIG. 4 is a side view showing an operation state of the sheet stacking device.

FIG. 5 is a side view showing an operation state of the paper stacking device, and FIG.
Continued.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Image forming apparatus, 20 ... Post-processing apparatus, 50 ... Paper loading apparatus, 52, 54, 56, 58 ... Loading tray, 60,
62, 64, 66 ... eccentric cam, 68, 70, 72, 74
... Motor, 76 ... Control unit, 78 ... Paper drop prevention member.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3F054 AA01 AC01 BA04 BA13 BD02 BD07 BG00 CA06 CA31 DA01 DA16

Claims (8)

[Claims] 1. A sheet stacking device for stacking and storing sheets discharged from a post-processing device connected to an image forming apparatus, comprising: a stacking tray divided into a plurality of sheets in a sheet discharging direction; And a control unit that controls to selectively move the stacking tray in accordance with a print mode set by the image forming apparatus, the post-processing device, or an external device. Paper loading device. 2. The sheet stacking apparatus according to claim 1, wherein said control means adjusts a lowering amount of said stacking tray according to the number of sheets to be discharged. 3. The sheet stacking apparatus according to claim 1, wherein the print mode includes a sheet folding process. 4. The sheet stacking apparatus according to claim 1, wherein said print mode includes a stapling process. 5. The sheet stacking apparatus according to claim 1, wherein the print mode includes continuous jobs having different sheet sizes. 6. A loading tray for loading and storing sheets discharged from a post-processing device connected to an image forming apparatus, and a sheet drop prevention member disposed adjacent to the loading tray in a direction orthogonal to a sheet discharging direction. And a paper stacking device. 7. The stacking tray is divided into a plurality of sheets in a sheet discharging direction, and each of the divided stacking trays is selectively selected according to a print mode set by the image forming apparatus, the post-processing apparatus, or an external device. 7. The sheet stacking device according to claim 6, wherein the sheet stacking device is vertically movable. 8. The sheet falling prevention member is capable of moving forward and backward with respect to the stacking tray, and is advanced to a position adjacent to the stacking tray at least during stacking of sheets. Or 7 paper loading device.