JPH10305958A - Sheet post-processing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To store a large volume of post-processed sheet bundle on a paper discharge tray by elevating/lowering a paper discharge tray means when a sensor detects that the volume of the discharged and loaded sheets reaches the prescribed maximum value, and discharging and loading the sheets from a sheet post-processing means to the other paper discharge tray means. SOLUTION: When the processed sheet bundle P is drawn from other paper discharge tray means, i.e., the paper discharge tray means on the upper stage 20 during or after the sheet post-processing, the self weight of the sheet bundle P on a movable paper discharge pan 21 is reduced, the movable paper discharge pan 21 is urged by a spring, and elevated, and a sensor PS1 or PS3 generates the signal of loading the sheet bundle P, and continues the sheet post-processing after the paper discharge tray means is moved. The sheet post-processing operation is continued by arbitrarily drawing the post-processed sheet bundle P on the upper and lower paper discharge tray means 20, 30 during the post- processing of the sheet, and a large volume of sheet bundles P can be post- processed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention receives a sheet on which an image is formed by an image forming apparatus such as an electrophotographic copying machine, a printer or a printing machine, and performs post-processing such as stapling by a stapler and shift processing. And a sheet post-processing apparatus that discharges the sheet onto a sheet discharge tray by a discharge unit.

[0002]

2. Description of the Related Art A sheet post-processing apparatus called a finisher is used as an apparatus for collating and binding a plurality of image-recorded sheets discharged from an image forming apparatus for each copy by a stapler.

The finisher has a function connected to an image forming apparatus main body such as a copying machine or a printer, and is driven in accordance with a sequence operation of a copy or print process.

Therefore, for an image forming apparatus capable of performing a large amount of image forming processes at a high speed, a finisher capable of performing a function at a high speed following the processing speed is required. .

A finisher capable of such high-speed processing has been disclosed in Japanese Patent Application Laid-Open Nos. 60-142359 and 60-142359.
Nos. 0-158463 and 62-239169, and JP-A Nos. 62-288002 and 63-267667.
The proposals in JP-A-2-27691 and JP-B-5-41991 are disclosed.

[0006] Sheets with images recorded thereon, which are carried out of the image forming apparatus main body, are sequentially stacked while being aligned in the intermediate stacker, and after storing one set of sheet bundles, sheet post-processing such as a stapler is performed, and binding is performed. The sheet bundle thus placed is conveyed on a discharge belt provided at the bottom of the intermediate stacker, further nipped by a pair of upper and lower discharge rollers and discharged to a discharge tray.

The sheet post-processing apparatus disclosed in Japanese Patent Application Laid-Open No. Hei 2-276691 has a structure in which two fur brushes are rotatably provided, and the tips of the fur brushes are brought into contact with a guide plate. The sheet post-processing apparatus disclosed in the paper storage device of Japanese Patent Application Laid-Open No. 1-214565 is configured to align a sheet by rotating a paddle wheel on which a plurality of blade members are radially mounted. JP-A-63-11
In the sheet post-processing apparatus disclosed in Japanese Patent No. 6168, a part of a belt whose lower end portion is in contact with an intermediate tray is wound around a lower roller of a pair of discharge rollers, and the belt rotates together with the lower roller to rotate on the intermediate tray. The sheet conveyed out is brought into contact with the stopper.

A sheet post-processing apparatus disclosed in Japanese Patent Application Laid-Open No. 1-127556 discloses a first and second sheet conveying apparatus for conveying a sheet sent from an image forming means to a sheet post-processing means.
One sheet conveying path, and conveying direction switching means for switching between the first and second sheet conveying paths, and conveying the sheet so as to be sent to the second sheet conveying path in accordance with the operation of the sheet processing means. It has control means for controlling the direction switching means.

The recording paper post-processing apparatus described in Japanese Patent Application Laid-Open No. 8-42728 is provided with one stapler and one corresponding paper discharge tray. Also, Japanese Patent Application Laid-Open
The sheet post-processing apparatus described in Japanese Patent Application No. 76190/1990 includes two staplers and two corresponding paper discharge trays.

The output paper processing apparatus described in Japanese Patent Application Laid-Open No. Hei 9-221263 is provided with a vertically-equipped three-stage paper discharge tray,
These paper discharge trays are fixedly arranged at predetermined intervals, and move up and down integrally.

[0011]

In a conventional sheet post-processing apparatus, a set of vertically movable paper discharges is provided for a set of sheet post-processing means (staplers, shift means, bookbinding means, punching means, etc.). In the configuration having the tray means, the entire discharge tray means is driven up and down by a drive source in accordance with the number of sheets stacked on the discharge tray means. Therefore, there is a limit to the maximum number of sheets that can be accommodated on one discharge tray.

Further, after the sheets output in different image forming modes (for example, the sheet output in the copy mode and the sheet output in the printer mode) are post-processed, respectively, the sheets are discharged onto the discharge tray. There is a problem that the sheets in the mode are mixed on the paper discharge tray, making it difficult to sort.

When sheets processed in different sheet post-processing modes (for example, staple-processed sheets and shift-processed sheets) are successively discharged onto a discharge tray, sheets in both modes are discharged onto the discharge tray. , It becomes difficult to sort.

A sheet post-processing apparatus provided with two sets of sheet post-processing means and two sets of discharge tray means which can move up and down has complicated structures and driving means.

A sheet post-processing apparatus comprising a set of sheet post-processing means and a plurality of discharge tray means integrally formed with a plurality of discharge trays is provided. In this case, since the integrated discharge tray unit is raised and lowered, there is a problem that the overall height of the apparatus is increased.

It is an object of the present invention to solve the above-mentioned problems and to (1) enable a large amount of post-processed sheet bundles to be stored on a discharge tray, and (2) output in different image forming modes. And (3) separating and accommodating sheet bundles processed in different sheet post-processing modes, and (4) the structure and driving means of the sheet post-processing apparatus. It is an object of the present invention to provide a sheet post-processing apparatus that simplifies (5) the overall height of the sheet post-processing apparatus.

[0017]

A sheet post-processing apparatus according to the present invention, which achieves the above object, post-processes an image-formed sheet carried out from an image forming apparatus by a sheet post-processing means, and then discharges a sheet bundle. In a sheet post-processing apparatus for discharging to a paper tray means, a set of sheet post-processing means, a plurality of discharge tray means for stacking a sheet bundle processed and discharged by the sheet post-processing means, and the discharge tray A sensor for detecting a predetermined maximum capacity of the sheet bundle stacked on the unit, and an elevating drive unit for raising and lowering the plurality of sheet discharge tray units. The sheet is discharged from the sheet post-processing unit to one of the sheet discharge tray units and stacked. When the sensor detects that the discharged sheet has reached the predetermined maximum capacity, it drives the elevating drive unit to move up and down the sheet discharge tray unit, and causes the sheet post-processing unit to discharge the other sheet. Discharged to the tray means, characterized in that to load (claim 1).

The object of the present invention is to provide a sheet post-processing apparatus for post-processing an image-formed sheet conveyed from an image forming apparatus by a sheet post-processing means and then discharging a sheet bundle to a discharge tray means. Sheet post-processing means, a plurality of discharge tray means for stacking the sheet bundle processed and discharged by the sheet post-processing means, and a lifting drive means for raising and lowering the plurality of discharge tray means, After the sheets formed in the image forming mode are discharged and stacked on one of the discharge trays, the discharge tray is raised and lowered, and the sheets formed in the other image forming mode are discharged to the other discharge tray. This is achieved by a sheet post-processing device characterized by stacking.

Further, the sheet post-processing apparatus according to the present invention is a sheet post-processing apparatus for post-processing an image-formed sheet carried out from an image forming apparatus by a sheet post-processing means, and then discharging the sheet to a paper discharge tray means. , A set of sheet post-processing means, two sets of vertically movable discharge tray means arranged at least in two upper and lower stages for stacking sheets processed and discharged by the sheet post-processing means, Drive means for driving the paper discharge tray means to move up and down, wherein the distance between the upper paper discharge tray means and the lower paper discharge tray means when discharging sheets to the upper paper discharge tray means is X, When the distance between the upper discharge tray means and the lower discharge tray means when the sheet discharge tray means and the lower discharge tray means are raised to discharge the sheet to the lower sheet discharge means is Y X <is it characterized in that set to Y (Claim 7).

[0020]

Next, an embodiment of a sheet post-processing apparatus according to the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a sectional view showing the structure of the sheet post-processing apparatus (finisher). The sheet post-processing apparatus is installed with its position and height adjusted so that the receiving portion of the sheet P coincides with the discharge port of the main body of the image forming apparatus (copier, printer, etc.), and corresponds to the operation of the main body of the image forming apparatus. Connected to a control system to be driven.

The P introduced into the movable guide plate 1 of the receiving section is conveyed while being nipped by a conveying roller pair 2 composed of a driving roller and a pinch roller, passes through a fixed guide plate 3, and passes through a sheet reversing conveying drum. Transport roller pair 5 above 4
And is conveyed onto the peripheral surface of the sheet reversal conveyance drum 4. The sheet reversing / conveying drum 4 is driven and rotated by a driving source (not shown). A sheet pressing member (gripper) 6 is swingably supported near the peripheral surface of the sheet reversing / conveying drum 4. The sheet pressing member is biased by a spring and is swung by a cam mechanism (not shown).

The leading end of the sheet P sent from the nip position of the pair of carrying rollers 5 to the peripheral surface of the sheet reversing / conveying drum 4 is connected to the leading end of the sheet pressing member 6 opened by the cam mechanism and the sheet reversing / conveying. The sheet enters the V-shaped gap between the drum 4 and the peripheral surface of the rotating sheet reversing / conveying drum 4, and is pressed and sandwiched between the peripheral surface of the rotating sheet reversing / conveying drum 4 and the tip of the spring-biased sheet pressing member 6. It is transported on the peripheral surface of the reverse transport drum 4. At the time of this sheet conveyance, the peripheral speeds of the conveyance roller pair 5 and the sheet reversal conveyance drum 4 are equal.

Above the movable guide plate 1 and the conveying roller pair 2, an uppermost sheet discharging means (non-sort tray) 7 is provided. The uppermost sheet discharging means 7 includes a sheet discharging tray 7A on the left side in the figure and a sheet discharging tray 7B on the right side in the figure around the fulcrum shaft 7C.
The paper discharge trays 7A and 7B can swing about the fulcrum shaft 7C in the direction of the dashed line arrow. Since the paper discharge tray 7B is unitized with the movable guide plate 1 and the transport roller pair 2, the swing of the movable guide plate 1 causes the movable guide plate 1 and the transport roller pair 2 to swing together. The movable guide plate 1, the conveying roller pair 2, and the paper discharge tray 7B indicated by solid lines in FIG. 1 indicate a path for conveying the sheet P discharged from the image forming apparatus to a sheet post-processing unit. The broken line in FIG. 1 indicates that the unit including the movable guide plate 1, the transport roller pair 2, and the paper discharge tray 7B is swung downward,
4 illustrates a path that enables a sheet that does not require sheet post-processing to be conveyed onto the discharge tray 7.

FIGS. 2 to 7 are partial sectional views showing a sheet conveying process of the sheet post-processing apparatus.

In FIG. 2, the leading end of the sheet P is
When the conveying roller pair 5 is accelerated during the process of pressing and holding the front end portion of the spring-biased sheet pressing member 6 on the peripheral surface of the rotating sheet reversing conveying drum 4 to convey the sheet, The leading end of the sheet P is sandwiched by the sheet pressing member 6, but the vicinity of the rear end of the sheet P is increased in speed by the pair of conveying rollers 5 to feed out the sheet P excessively. The outer peripheral surface of the drum 4 is swelled outwardly.

In FIG. 3, when the sheet reversing / conveying drum 4 continues to rotate further, the moment the rear end of the sheet P separates from the nip position of the conveying roller pair 5, the conveying force of the conveying roller pair 5 is reduced. The sheet P is inverted due to the rigidity of the sheet P, and is separated from the peripheral surface of the sheet inversion transport drum 4. Discharge arm 14 in which the leading end of sheet P is stopped near stapler 10
When the sheet pressing member 6 reaches the leading end 14A and stops, the sheet pressing member 6 is separated from the sheet P.

As the sheet reversing / conveying drum 4 continues to rotate further, as shown in FIG. 4, two sheet aligning members 8A, 8B rotatably supported at two positions in the sheet reversing / conveying drum 4. Successively rubs the vicinity of the leading end of the sheet P so that the leading end of the sheet P is
The sheet P is stopped in contact with A, and the sheets P are aligned in the transport direction. The trailing end of the aligned sheet P is a movable sheet discharge tray 2.
1.

In the process shown in FIG. 5 in which the leading end of the sheet P is brought into contact with the leading end 14A of the discharge arm 14, the alignment plate of the shift aligning means 9 described later moves in the width direction of the sheet P (perpendicular to the sheet conveying direction). Direction) (paper width alignment). Alternatively, when the shift mode is set,
The width alignment is performed by alternately shifting the alignment plate to a plurality of predetermined positions. After the sheet reversing / conveying drum 4 completes one rotation and the positioning of the first sheet P is completed, the second sheet P is fed to the sheet reversing / conveying drum 4, and the same conveyance as described above is performed, and the positioning is performed. And stop. When the number of sheets P positioned and brought into contact with the leading end portion 14A reaches a predetermined number, staples are driven into the predetermined positions of the sheets P by the stapler 10 and bound (see FIG. 5). Alternatively, when the shift mode is set, the shift operation by the matching plate is performed.

FIG. 6 shows a state in which the sheet P that has been subjected to the sheet post-processing such as the staple processing or the shift processing is discharged to the movable discharge tray 21.

The drive motor M2 includes gears G7, G8, G
The disk 12 is driven to rotate via a gear train consisting of G9 and G10. The other end of the crank 13, one end of which is supported at an eccentric position of the disk 12, is rotatably supported by a part of a discharge arm 14 that can swing about a fulcrum shaft 15. The disk 12 driven and rotated by the drive source causes the crank 13 to eccentrically move, and further causes the discharge arm 14 to swing. Due to the swinging movement of the discharge arm 14, the leading end 14A of the discharge arm 14 presses the leading end of the sheet P that has completed the sheet post-processing, and the distal end 14A is moved from the position in contact with the leading end 14A to the movable discharge tray 21. Extrude toward The sheet P pushed out by the discharge arm 14 slides on the upper surface of the movable paper discharge tray 21, and then the leading end of the sheet P descends by its own weight, and a stopper surface provided on the frame 23 supporting the movable paper discharge tray 21. 23
Stops on contact with 1. The tip portion 14A is the stopper surface 23
The sheet bundle advances to the movable sheet discharge tray 21 side from the vertically upper side of 1, so that the sheet bundle is surely transferred to the stacking unit without remaining in the processing unit.

The movable discharge tray 21 is swingably supported by a fulcrum shaft 24 that is implanted in a frame 23. A swing lever 2 is provided on the bottom surface of the movable discharge tray 21 at the right end in the figure.
5 comes into contact with each other, and the movable paper discharge tray 21 is moved up and down. The base of the swing lever 25 is pivotally supported by a fulcrum shaft 26 and is swingable. A swing lever 25 is attached to one end of the fulcrum shaft 26.
The locking member 27, which is integral with the first member, is swingable. The locking member 27 is urged by a spring 28 to raise the tip of the swing lever 25. As a result, the leading end of the movable sheet discharge tray 21 is lifted and swings about the fulcrum shaft 24 in the counterclockwise direction shown in the figure. Since the tip claw portion of the locking member 27 is removably locked to the locking portion 232 provided on the frame body 23, the swing lever 25 is prevented from swinging to a predetermined position or more. The distal end of the movable paper discharge tray 21 is held at a predetermined height by being biased by a spring.

As shown in FIG. 7, when the number of the post-processed sheets P stacked on the movable discharge tray 21 gradually increases, the leading end of the movable discharge tray 21 is moved by the spring 2 due to its own weight.
8, the locking member 27 and the locking portion 232 are unlocked by depressing the swing lever 25, and the leading end of the movable discharge tray 21 is gradually lowered. I will do it. During the lowering process of the movable paper discharge tray 21, the post-processed sheet P is discharged from a post-processing unit (stapler, shift processing unit) on the uppermost layer of the sheets P stacked on the movable paper discharge tray 21. Held in position.

After the post-processed sheets P stacked on the movable discharge tray 21 gradually increase, the movable discharge tray 21 gradually descends and reaches the lower limit position. The provided actuator (not shown) is detected by a sensor PS2 fixed on the sheet post-processing apparatus main body side,
The detection signal is sent to a control unit 80 described later. Note that the sensor PS1 may be installed on the frame 23 to detect the lower limit position of the movable sheet discharge tray 21.

The post-processed sheet P is placed on the movable discharge tray 21.
When paper is discharged, the interval X between the upper discharge tray means 20 and the lower discharge tray means 30 is set to a minimum.

FIG. 8 is a sectional view showing the driving of the sheet discharge tray means in the sheet post-processing apparatus provided with the two-stage sheet discharge tray means. Since the upper discharge tray means 20 and the lower discharge tray means 30 have the same structure, the same reference numerals will be used in the following description. In FIG. 1, the upper discharge tray 20 and the lower discharge tray 30 are lowered to the bottom dead center, and the post-processed sheet P is stored in the upper discharge tray 20. Indicates the status. FIG. 8 shows a state in which the upper discharge tray 20 and the lower discharge tray 30 are raised to the top dead center, and the post-processed sheet P is stored in the lower discharge tray 30. . Hereinafter, the lifting structure and operation of the upper discharge tray means 20 and the lower discharge tray means 30 will be described with reference to FIGS.

The sensor PS2 detects that the post-processed sheets P stacked on the movable discharge tray 21 of the upper discharge tray means 20 are full (upper limit of the stacking amount) and generates a signal. Then, the control unit (not shown) operates
The drive motor M1 for raising and lowering the tray is driven to raise the upper discharge tray means 20. That is, the drive motor M1
Drives G1, G2, G3, G4, G5, G
The gear train composed of 6 drives and rotates the drive pulley 41.
Between the driving pulley 41 and the upper driven pulley 42,
The drive wire 43 is wound. By the driving rotation of the driving pulley 41, the driving wire 43 reciprocates in the vertical direction.

The base of the frame 23 of the upper discharge tray means 20 is fixed to a part of the drive wire 43 by a discharge tray hanging member 44. The frame 23 of the upper discharge tray means 20 and the frame 23 of the lower discharge tray means 30
And are connected by a connecting rod 45. That is, a long groove 451 is formed in the connecting rod 45, and a pin 46 fixed to the frame body 23 of the upper sheet discharging tray means 20 comes into sliding contact with the connecting rod 45 (see FIG. 1). The vicinity of the lower end of the connecting stick 45 is fixed to the frame 23 of the lower sheet ejection tray means 30.

When the upper discharge tray means 20 is moved upward by the driving wire 43, the pins 46 fixed to the frame 23 of the upper discharge tray means 20 are inserted into the long groove portions 451 of the connecting rod 45. In sliding contact, only the upper discharge tray means 20 is moved upward. When the pin 46 abuts on the uppermost end of the long groove 451 of the connecting rod 45, the moved upper discharge tray means 20 and the stopped lower discharge tray means 30 have a maximum separation distance.

The upper discharge tray means 20 includes the drive wire 4
3, the pin 46 of the upper discharge tray 20 moves the connecting stick 45 upward in a state of contact with the long groove 451, and is fixed to the lower end of the connecting stick 45. The lower discharge tray means 30 is lifted and moved. Therefore, the upper discharge tray means 20 and the lower discharge tray means 30 move upward integrally while maintaining the maximum separation interval.

The upper discharge tray means 20 is provided with the drive wire 4
3, the upper end of the frame 23 of the upper discharge tray means 20 is moved upward by the uppermost discharge means 7.
Of the paper discharge tray 7A on the left side in the figure, and push up the paper discharge tray 7A. As a result, the discharge tray 7A is
It is swung clockwise around the fulcrum shaft 7C and retracts.

When the detection means (sensor) PS5 detects that the upper discharge tray means 20 has reached the top dead center, the drive motor M
1 is stopped, and the upper discharge tray 20 and the lower discharge tray 30 are stopped. At this time, the lower discharge tray 30 stops at a position for receiving the sheet P after the post-processing by the stapler 10.

The movable discharge tray 3 of the lower discharge tray means 30
When the post-processed sheet P is discharged onto the sheet 1, the interval Y between the upper discharge tray means 20 and the lower discharge tray means 30, as shown in FIG.
(Size) of the sheet P is separated from the sheet reversing / conveying drum 4 and the conveying roller pair 5 and is reversed by drawing a trajectory shown by a broken line, on the movable discharge tray 21 of the upper discharge tray means 20. Is set so that the rear end of the maximum size sheet P does not contact the bottom of the upper sheet discharge tray means 20 during the operation.

FIG. 9 is a configuration diagram of the sheet post-processing apparatus showing a driving state when the sheet P is discharged to the upper discharge tray means 20.

The guide rollers 47 supported by the frame 23 of the upper discharge tray means 20 roll on guide rails 48 vertically supported by the apparatus main body and can be moved up and down. Also,
The frame 23 is fixed to a part of a drive wire 43 stretched in the vertical direction of the lifting drive means 40 via a discharge tray hanging bracket 44, and moves up and down with the rotation of the drive wire 43.

The guide roller 47 supported by the frame 33 of the lower sheet discharge tray means 30 can roll on a guide rail 48 and can move up and down. Locking part 3 provided in part of frame 33
The other end of the long tension spring 49 locked to 31 is locked to a locking portion 491 provided at the top of the apparatus main body.
Therefore, the lower discharge tray means 30 is provided with the tension spring 4
9 urged upwards to balance the weight,
The ascending drive is possible with a light load.

The lower end of the connecting rod 45 is connected and fixed to the frame 33 by a locking portion 452. This connecting rod 45
Are vertically supported by the frame 33, and the upper half thereof has a long groove 4
51 are drilled. At the lower end of the long groove 451, a pin 4 implanted in the frame 23 of the upper sheet discharging tray 20 is provided.
6 are fitted. Therefore, in this paper discharge state, the upper discharge tray means 20 does not allow the pin 46 to
1 and is held in a stopped state by abutting on the lower end.

That is, in this paper discharge state, the interval X between the stop position of the pin 46 at the lower end of the long groove 451 of the connecting rod 45 and the engaging portion 452 at the lower end of the connecting rod 45 is equal to the upper discharge tray. This is the interval between the unit 20 and the lower discharge tray unit 30, and is set at the shortest interval as long as the two discharge tray units and the stacked sheets do not interfere with each other.

FIG. 10 is a configuration diagram of the sheet post-processing apparatus showing a driving state when the sheet P is discharged to the lower discharge tray means 30.

The driving wire 4 is driven by the driving motor M1.
When the tray 3 rotates and the upper discharge tray means 20 is pulled up, the pins 46 implanted by the frame 23 rise along the long groove 451 of the entire length L. Pin 46 is long groove 45
When the frame 23 comes into contact with the upper end of the frame 1 and the frame 23 further rises, the connecting rod 45 is pulled up by the pin 46, and at the same time, the lower discharge tray means 30 is also pulled up via the locking portion 452.

When the lower discharge tray 30 reaches a predetermined discharge position and stops, the upper discharge tray 20
The distance Y between the upper discharge tray 20 and the lower discharge tray 30 is larger than the initial distance X between the upper discharge tray 20 and the lower discharge tray 30, and Y = X + L. Here the long groove 4
The total length L of the sheet 51 is set so as to maintain an interval Y such that the sheet P discharged from the sheet reversing / conveying drum 4 is placed on the discharge tray of the lower discharge tray means 30 without any trouble.

FIG. 11 is a plan view of the discharge tray means 20 (30). The movable paper discharge tray 21 is arranged at the center of the discharged sheet P in the width direction and is swingably supported. Two fixed discharge trays 22 are fixed to the frame 23 on both sides of the movable discharge tray 21 in the sheet width direction.

A total of four guide rollers 47 are rotatably supported on both sides of the base of the frame 23 in the sheet width direction and up and down. When the guide roller 47 moves along the sliding surface of the guide rail 48 fixed to the sheet post-processing apparatus main body, the upper discharge tray unit 20 and the lower discharge tray unit 30 move up and down, respectively. .

FIG. 12 is a front view of the shift matching means 9.

The shift aligning means 9 includes one aligning plate 91A.
And a second unit 90 on the right side of the drawing for moving the other matching plate 91B.
B. These two units 90A and 90B are
Since the first unit 90A has almost the same structure, the first unit 90A will be described below.

The alignment plate 91A is fixed to a carriage 94A which is movable by sliding on a guide bar 93A fixedly supported in the unit housing 92A. The carriage 94
A includes a fixing member 9 attached to a part of a timing belt 97A stretched between a driving pulley 95A and a driven pulley 96A.
8A. The drive pulley 95A is driven and rotated by a drive motor M3 as a drive source via gears G11 and G12. PS6A and PS6B are home position sensors. Each of the alignment plates 91A and 91B has a dedicated drive motor, and is independently movable.

FIGS. 13A and 13B are schematic diagrams showing the operation of the alignment plates 91A and 91B during the stapling process.

When the stapling process is performed on a sheet P of a normal size, the alignment plates 91A and 91B are opposed to the center line R in the conveying direction of the sheet P at an equal distance as shown in FIG. The sheet P is located at an initial position wider than the sheet width, and the sheet P is sent from the sheet reversing conveyance drum 4 to the stapler 10 and the leading end 14A of the discharge arm 14 is
Each time the sheet P comes into contact with the sheet P, it starts moving from the initial position and strikes the side edge of the sheet P to adjust the width.

When a stapling process is performed on a small-sized (for example, A5 size) sheet P, as shown in FIG. 13B, each time the sheet P is fed from the sheet reversing conveyance drum 4 to the stapler 10 and comes into contact with the leading end portion 14A. The one matching plate 91B starts moving from the initial position and presses the side edge of the sheet P to shift the sheet P, and the other matching plate 91A starts moving from the initial position and moves the side edge of the sheet P. Hit to align the width.

FIGS. 14A and 14B are schematic views showing the operation of the matching plates 91A and 91B during the shift processing.

FIG. 14A shows a state where an odd-numbered sheet bundle is processed. When the shift mode (offset mode) is set, the alignment plates 91A and 91B move the same distance from an initial position that is equidistant with respect to the center line R in the conveyance direction of the sheet P, and the sheet width corresponds to the sheet size. Stopping at a slightly wider first position, the sheet bundle is received, post-processed and discharged.

FIG. 14B shows a state in which the even-numbered sheet bundle is shifted. After the even-numbered sheet bundle is received at the same position as the odd-numbered sheet bundle, the matching plates 91A, 9
1B moves and stops at a position unequal to the center line R in the transport direction of the sheet P, and is post-processed and discharged. Note that the width alignment may be performed in this shift mode.

FIG. 15 is a block diagram showing the control of the sheet post-processing apparatus according to the present invention.

In FIG. 1 and FIG.
Sensors PS1, PS2, PS3 for detecting the lower limit position of 1
Sends a detection signal indicating that the sheet P on the movable discharge tray 21 is full (upper limit of the stacking amount) at the respective stop positions of the discharge tray means 20 and 30 to a control unit 80 described later.
That is, the sensor PS1 detects the lower limit position of the movable discharge tray 21 at the bottom dead center position of the lower discharge tray unit 30. The sensor PS2 detects the lower limit position of the movable discharge tray 21 at a position where the upper discharge tray 20 and the lower discharge tray 30 are discharged onto the movable discharge tray 21 after the sheet post-processing. The sensor PS3 detects the lower limit position of the movable paper discharge tray 21 at the top dead center position of the upper paper discharge tray means 20.

In the following, the elevation of the upper and lower discharge tray means 20, 30 and the control by the sensors PS1 to PS3 will be described.

(1) In the sheet post-processing apparatus, the sheet bundle after the sheet post-processing is stacked on the movable discharge tray 21 of the upper discharge tray means 20, reaches the lower limit position, and the sheet P is full. Is detected by the sensor PS2, a detection signal is sent to the control unit 80. The control unit 80 drives the drive motor M1 in response to the detection signal, raises the upper discharge tray unit 20, and lowers the lower discharge tray unit 30.
Follow the upper discharge tray means 20 and rise.

(2) After the lower discharge tray means 30 stops at a predetermined sheet post-processing position, a sheet bundle after sheet post-processing is stacked on the movable discharge tray 21 of the lower discharge tray means 30, When the sensor PS2 detects that the sheet P has reached the lower limit position and is full, the detection signal is sent to the control unit 80.
Send to When the sheets P on both the discharge tray means 20 and 30 are full, the sheet post-processing is stopped.

(3) During the above-mentioned sheet post-processing, if the sheet P on which the sheet post-processing has been performed on both the discharge tray means 20 and 30 is extracted, the weight of the sheet P on the movable discharge tray 21 becomes lighter. Then, the movable discharge tray 21 is moved upward by the bias of the spring, and the sensor PS2 emits a signal indicating that the sheets P can be stacked, and the sheet post-processing is continued.

(4) During the above-mentioned sheet post-processing or after the sheet post-processing, from another discharge tray means (lower discharge tray means 30 in FIG. 1 or upper discharge tray means 20 in FIG. 8). Sheet P after sheet post-processing
Is removed, the weight of the sheet P on the movable sheet discharge tray 21 becomes lighter, the movable sheet discharge tray 21 is urged by a spring and rises, and the sensor PS1 or PS3 issues a signal indicating that the sheet P can be stacked. After the sheet discharge tray has moved, the sheet post-processing is continued.

In this manner, during the sheet post-processing, the sheet P having been subjected to the sheet post-processing on the upper and lower discharge tray means 20 and 30 is arbitrarily extracted, so that the sheet post-processing operation is continued, and The sheet P can be post-processed.

Further, a sheet post-processing means comprising one stapler 10 and one shift aligning means 9 and upper and lower discharge tray means 20 for stacking a sheet bundle processed and discharged by the sheet post-processing means, 30 and a lifting drive means 40 for raising and lowering the plurality of upper and lower discharge tray means 20, 30. The sheet P formed in the staple processing mode is discharged onto one discharge tray means 20 (or 30). Stacked, and the paper discharge tray means 20 (or 3
0) is raised and lowered, and the sheet P formed in the shift processing mode can be discharged and stacked on the other discharge tray means 30 (or 20). This makes it possible to easily continue the staple process and the shift process.

In the embodiment of the present invention, a sheet post-processing apparatus connected to a copying machine has been described. However, a sheet post-processing apparatus used in connection with an image forming apparatus such as a printer or a facsimile or a light printing machine. Is also applicable.

[0073]

According to the sheet post-processing apparatus of the present invention, the following excellent effects can be obtained.

(1) Sheet post-processing means, a plurality of discharge tray means for stacking the sheet bundles processed and discharged by the sheet post-processing means, and a predetermined number of sheet bundles stacked on the discharge tray means A sensor for detecting a maximum capacity, an elevating drive unit for elevating and lowering the plurality of discharge tray units, and a control unit. When the sensor detects that the maximum stacking amount has been reached, the lifting drive unit is driven to raise and lower the discharge tray unit, and is discharged from the sheet post-processing unit to another discharge tray unit, and is stacked. It is possible to stack and store a large number of sheets continuously. Also, during this sheet post-processing, if the post-processed sheet is taken out, the sheet post-processing is continued,
Productivity is improved by efficiently executing a large amount of sheet post-processing without delaying or stopping image formation and continuous discharge of the image forming apparatus (claim 1).

(2) A sheet post-processing means comprising a stapler and a shift aligning means, a discharge tray means for stacking a sheet bundle processed and discharged by the sheet post-processing means, and the plurality of discharge tray means A lifting / lowering drive means for raising / lowering the sheet, discharging and stacking the sheets formed in the staple processing mode to any one of the paper discharge tray means, and then raising and lowering the paper discharge tray means to separate the sheets formed in the shift processing mode; By discharging and stacking the sheets on the sheet discharge tray means, the staple processing and the shift processing can be separated, and the processing can be easily and continuously performed. In addition, since the sheet transporting means and the sheet discharging means are not required, excellent effects such as the downsizing of the sheet post-processing apparatus can be obtained (claim 2).

(3) The structure and driving means of the sheet post-processing apparatus can be simplified, and the overall height of the sheet post-processing apparatus can be reduced. (Claim 7)

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a configuration of a sheet post-processing apparatus of the present invention.

FIG. 2 is a partial sectional view showing a sheet conveying process (1) of the sheet post-processing apparatus.

FIG. 3 is a partial cross-sectional view illustrating a sheet conveying process (2) of the sheet post-processing apparatus.

FIG. 4 is a partial sectional view showing a sheet conveying process (3) of the sheet post-processing apparatus.

FIG. 5 is a partial sectional view showing a sheet conveying process (4) of the sheet post-processing apparatus.

FIG. 6 is a partial sectional view showing a sheet conveying process (5) of the sheet post-processing apparatus.

FIG. 7 is a partial sectional view showing a sheet conveying process (6) of the sheet post-processing apparatus.

FIG. 8 is a cross-sectional view illustrating driving of a sheet discharge tray unit in a sheet post-processing apparatus including a two-stage sheet discharge tray unit.

FIG. 9 is a configuration diagram of a sheet post-processing apparatus showing a driving state when a sheet is discharged to an upper discharge tray unit.

FIG. 10 is a configuration diagram of a sheet post-processing apparatus showing a driving state when a sheet is discharged to a lower discharge tray unit.

FIG. 11 is a plan view of a paper discharge tray unit.

FIG. 12 is a front view of a shift matching unit.

FIG. 13 is a schematic view showing the operation of the matching plate during stapling processing.

FIG. 14 is a schematic view showing the operation of the matching plate during the shift processing.

FIG. 15 is a block diagram illustrating control of the sheet post-processing apparatus according to the present invention.

[Explanation of symbols]

Reference Signs List 4 sheet reversing conveyance drum 5 conveyance roller pair 6 sheet pressing member 7 uppermost sheet discharge means 9 shift alignment means (sheet post-processing means) 10 stapler (sheet post-processing means) 14 discharge arm 20 upper sheet discharge tray means 21 movable Discharge tray 22 Fixed discharge tray 23 Frame 25 Swing lever 28 Spring 30 Lower discharge tray means 40 Elevation drive means 43 Drive wire 44 Discharge tray hanging bracket 45 Connecting rod (lifting plate) 46 Pin 47 Guide roller 48 Guide rail 49 Tension spring 80 Control unit 91A, 91B Alignment plate M1, M2, M3 Drive motor PS1, PS2, PS3, PS4, PS5, PS6A,
PS6B Sensor R Center line in the transport direction X, Y Interval between upper and lower discharge trays

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Kazuki Hinomi, Inventor 873-10, Terao, Kawagoe-shi, Saitama (10) Inventor: Mamoru Tomotsu, 2-6-1, Nakamachi, Asaka-shi, Saitama (72) Inventor: Yoshihiko Nishimoto 73-1, Yudaira, Akiruno-shi, Tokyo

Claims (9)

[Claims] An image-formed sheet carried out of an image forming apparatus is post-processed by a sheet post-processing means,
In a sheet post-processing apparatus that discharges a sheet bundle to a discharge tray means, a set of sheet post-processing means, a plurality of discharge tray means for stacking sheets processed and discharged by the sheet post-processing means, A sensor for detecting a predetermined maximum stacking amount of the sheet bundle stacked on the sheet discharge tray means, an elevating drive means for elevating the plurality of sheet discharge tray means, and a sheet post-processing means to any one of the sheet discharge tray means When the sensor detects that the discharged and stacked sheets have reached a predetermined maximum stacking amount, the elevation driving unit is driven to move the sheet ejection tray unit up and down, and from the sheet post-processing unit to another sheet ejection tray unit. A sheet post-processing apparatus, comprising: a control unit that controls discharge and stacking. 2. An image forming apparatus according to claim 1, wherein the image forming apparatus carries out the post-processing of the sheet on which the image has been formed and which has been carried out from the image forming apparatus.
In a sheet post-processing apparatus that discharges a sheet bundle to a discharge tray means, a set of sheet post-processing means, a plurality of discharge tray means for stacking the sheet bundle processed and discharged by the sheet post-processing means, Elevating drive means for raising and lowering the plurality of discharge tray means, a non-post-processing discharge tray for stacking sheets discharged without passing through the sheet post-processing means, and a predetermined image forming mode. After the discharged sheets are discharged and stacked on any one of the discharge trays, the discharge tray is moved up and down as necessary to discharge and stack the sheets formed in different image forming modes on another discharge tray. A sheet post-processing apparatus comprising: 3. The sheet post-processing apparatus according to claim 1, wherein the sheet post-processing unit is a stapling unit that binds sheets on which images have been formed. 4. The sheet post-processing apparatus according to claim 1, wherein the sheet post-processing unit is a shift unit that shifts an image-formed sheet in a direction orthogonal to a conveying direction. 5. The apparatus according to claim 1, wherein said lifting drive means is driven by a single drive source, said plurality of discharge tray means are connected by connection means, and are simultaneously raised and lowered by said drive source. The sheet post-processing apparatus according to any one of claims 4 to 4. 6. The sheet discharging tray means has a movable sheet discharging tray, and when a sheet having been subjected to sheet post-processing on any one of the sheet discharging tray means is removed during the sheet post-processing, the movable sheet discharging tray means is movable. 3. The sheet post-processing apparatus according to claim 1, wherein the sheet tray is spring-urged and rises, and the sensor emits a signal indicating that the sheets P can be stacked, thereby continuing the sheet post-processing. 7. After the image-formed sheet carried out of the image forming apparatus is post-processed by a sheet post-processing means,
In a sheet post-processing apparatus for discharging sheets to a sheet discharge tray means, a set of sheet post-processing means and two sets of at least two upper and lower stages for stacking the sheets processed and discharged by the sheet post-processing means Upper and lower discharge trays when discharging sheets to the upper discharge tray means, the discharge tray means being capable of moving up and down, and driving means for driving the two sets of discharge tray means to move up and down. The distance between the upper discharge tray means and the lower discharge tray means is X, and the upper discharge tray means and the lower discharge tray means are raised to discharge sheets to the lower sheet discharge means. A sheet post-processing apparatus wherein X <Y, where Y is the distance between the sheet and the discharge tray means. 8. The sheet post-processing apparatus according to claim 7, wherein the driving unit is connected to the upper sheet discharging unit. 9. The lower sheet discharging tray means is connected to the upper sheet discharging means via a connecting rod, and the distance between the lower sheet discharging means and the upper sheet discharging means is variable in response to the upper sheet discharging means. The sheet post-processing apparatus according to claim 7, wherein the sheet post-processing apparatus moves up and down.