JPH1087152A - Sheet loading device - Google Patents

Abstract

[PROBLEMS] To provide a sheet stacking apparatus capable of aligning sheets on each tray even if sheets of different sizes are discharged to each tray. Camshafts 2a, 2b
The tray 3 moves up and down according to the cylindrical groove cams 4a and 4b which are driven to rotate. A notch 3a is formed at one side edge of the tray, and the other side edge is a side wall 3b protruding upward. An alignment bar 28 is provided so as to be slidable laterally in a notch provided in a tray located at a sheet discharge port. The alignment bar contacts a side edge of a sheet on a tray to be processed by sliding horizontally, The side wall is urged. The alignment bar is set in such a size that it does not come into contact with other trays positioned above and below when sliding horizontally, so that only the sheet bundle on the tray to be processed can be biased and aligned.

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 applied as a sorter mechanism of, for example, a copying machine or a printer, and more particularly to a sheet stacking mechanism applied to a sorter mechanism with a stapler.

[0002]

2. Description of the Related Art As is well known, many modern copying machines have a sorter mechanism. In other words, there are a number of trays at the positions where the copied and discharged sheets are received. The trays are arranged vertically at appropriate intervals, and there are a type in which a large number of trays move up and down simultaneously, and a type in which each tray moves up and down sequentially and individually. By this vertical movement, a certain tray is positioned at the sheet discharge port of the copying machine body, and the discharged sheet is placed on the tray. This type of mechanism is described in detail, for example, in Japanese Patent Publication No. 63-35540.

[0003] In a high-function type copying machine, a stapler is attached to a sorter mechanism. That is, it is a mechanism for stopping the sheet bundle stacked on the tray with a staple. In this case, in a normal state, the tray group that moves up and down and the stapler are separated from each other so as not to interfere with each other. Then, there are a stapler movable type in which the stapler itself slides closer to the tray on which the sheet bundle is placed at the time of operation, and a stapler fixed type in which the tray at a specific position slides forward and backward to approach the stapler.

Further, when stapling the sheet bundle, it is necessary to align the side edges of the sheet bundle. As such a matching device, for example, Japanese Patent Laid-Open No. 6-19946
No. 7 discloses this in detail. That is, a slit is formed at the same position of each tray, and a rod-shaped alignment bar is provided so as to penetrate the tray group. The alignment bar is vertically arranged so as to penetrate the slit of each toilet, and moves along the slit. The moving distance of the alignment bar is changed according to the size of the sheet, and the side edge of the sheet bundle placed on each tray is urged by the alignment bar. Accordingly, the sheet bundle urged by the alignment bar moves to the opposite side, and the sheet bundle abuts on the side wall of the tray and is aligned.

[0005]

By the way, a sorter mechanism with a stapler on which a conventional alignment bar is mounted (also referred to as a sheet stacking apparatus in this specification) is mounted on the discharge side of an analog copying machine and performs staple processing. This was for documents of the same size, so that the above mechanism could also cope with the problem.

However, with the recent spread of digital copiers and printers, sheets of different sizes can be output to each tray, and such demands have been generated. Further, when a single printer is shared as an output device of an information processing device such as a plurality of personal computers and word processors, a sheet stacking device having a plurality of trays is attached to an output side of the printer, and each information processing device is previously set. Decide which tray to use. Then, when the operator of each information processing device issues a printout command at an arbitrary timing,
The specified tray is moved to a sheet discharge port of the printer, and a specified number of sheets are discharged onto the tray. Such a system is commercially available from Fuji Xerox Co., Ltd. under the trade name of a mailbox (a printer option).

When the stapler function is to be implemented in the various systems described above, there is a possibility that sheets of different sizes are stacked on each tray, and in such a case, alignment is performed with the conventional mechanism. There is a problem that the processing cannot be performed and the stapler function cannot be used. In particular, when implemented in the above-described shared printer, output instructions are given from a plurality of information processing apparatuses in a certain short period of time, or output instructions from a single information processing apparatus a plurality of times (instructions to discharge to different trays). May be added). Then, it is quite possible that sheets of different widths are stacked on a plurality of trays.

Even if the stapling process is not performed, if the side edges of the sheet bundle are aligned by an alignment bar or the like, it is easy to take out the sheet bundle from the tray. This is preferable because it is not necessary to perform a process of aligning them, but it cannot be realized by the conventional alignment mechanism for the same reason as described above.

Further, generally, the installation position of the printer is
In many cases, the user is away from the operator of the information processing apparatus.
Then, there is a case where a printout is not immediately taken. As a result, it is not possible to know how many sheets are stacked on the tray, and there is a possibility that more than the allowable number of sheets are printed out. Therefore, there is a problem that a paper jam occurs and the printer system stops.

SUMMARY OF THE INVENTION The present invention has been made in view of the above background, and an object of the present invention is to solve the above-mentioned problem, and to provide a structure in which sheets of different sizes are discharged to each tray.
Sheets on each tray can be aligned,
It is an object of the present invention to provide a sheet stacking apparatus capable of discharging sheets onto a predetermined tray without causing a paper jam or the like, and realizing each of the above objects with a simple configuration with a small number of parts.

[0011]

In order to achieve the above-mentioned object, in a sheet stacking apparatus according to the present invention, a tray (also referred to as a "bin") for placing sheets is lowered or raised to a predetermined position. A sheet stacking device, wherein a locking portion for alignment is provided on one side edge of the tray, and a cutout portion is provided on a side edge of the tray opposite to the locking portion, and the notch is provided at the predetermined position. An alignment bar is provided so as to be slidable horizontally in the notch provided in the certain tray,
The alignment bar comes into contact with the side edge of the sheet on the tray to be processed by sliding horizontally, and urges the locking portion side. The size and shape are set so as not to come into contact with a tray other than the tray to be processed when sliding, and the alignment bar is set so as not to interfere with the tray when moving the tray up and down (claim Item 1). In the embodiment, the locking portion provided on the tray is the side wall 3b formed integrally with the tray 3, but it is of course possible to attach another member.

With this configuration, the tray is moved up and down to a predetermined position, that is, at a sheet discharge port, and the discharged sheets are received by the tray. Thereafter, the alignment bar is slid laterally to urge the side edge of the sheet toward the locking portion.
Then, the sheet urged by the alignment bar moves toward the locking portion and is abutted against the locking portion, so that the side edges thereof are aligned and aligned. When the alignment bar slides sideways, it does not come into contact with the trays located above and below the tray to be processed. Therefore, even if the upper and lower trays are larger than the sheet placed on the tray being processed, Even in the case where the sheet is placed, it is possible to urge only the sheet on the tray to be processed without being affected by the other sheets and trays.

Therefore, the alignment process can be performed for each tray,
For example, sheets of different paper sizes are discharged to each tray by the stack method or the like, and even when the sheets are on, it is possible to perform the alignment process on each sheet. In the embodiment, the alignment process is performed each time one sheet is discharged. However, the present invention is not limited to this. It is also possible to slide and perform the matching process collectively.

Further, since alignment processing can be performed on a tray basis, alignment processing is performed on a sheet bundle discharged onto a certain tray, and alignment processing is performed on a sheet bundle discharged onto another tray. Can be controlled so as not to perform.

In the present invention, the function of stapling is not necessarily required as long as the alignment processing can be performed on a tray basis. In other words, if the side edges of the sheet bundle are aligned, it will be easier to take out when taking out from the tray,
Normally, the sheet bundle taken out of the tray is subjected to the process of manually aligning the side edges, but this process is not required in the present invention.

As described above, the staple unit is not essential, but a staple unit for stapling the end of the bundle of sheets stacked on the tray to be processed may be further provided. Good (claim 2). With this configuration, stapling can be performed on the sheet bundle that has been subjected to the alignment processing. In addition,
When the staple unit is provided, it is not necessary to always operate the staple unit when the alignment process is performed (of course, such a configuration may be employed). Only the alignment process is performed on the sheets discharged on a certain tray, and the sheets discharged on another tray are stapled on the aligned sheet bundle. Different processing can be performed.

Further, it is possible to provide a sensor for detecting whether or not the tray for receiving the discharged sheets is in a full load state, and to perform a discharging process on the stackable trays. In other words, the amount that can be loaded on the tray is determined in advance, and if you try to load more than that,
There is a possibility that the sheet cannot be discharged and a paper jam occurs.
Therefore, such a paper jam can be prevented beforehand by detecting the full load state. In particular, if there is a printer or a copier equipped with the sheet stacking device of the present invention at a position distant from the operator, or if the operator leaves after a printout (sheet discharge) command, sheets may not be placed on the tray. Although it is not known if a sheet larger than the allowable stacking amount is to be discharged, it is preferable in the present invention because such a sheet is automatically discharged to another tray.

In the present invention, the sensor for detecting the full load state is not only for detecting that the sheets of the allowable load amount are stacked on the tray, but also for taking a certain margin, In some cases, when a certain amount is reduced from the capacity by a predetermined amount, it is detected as a full state.

Further, the sensor according to the third aspect and a sensor for detecting a state of a sheet on a tray other than the sensor (for example,
In the case where a device for detecting the presence or absence of a sheet is provided, it can be simply provided for each tray. Further, instead of providing such a sensor on each tray, such a sensor may be attached to the alignment bar (claim 4).
Then, the alignment bar moves to the tray side each time the alignment process is performed, so that the sensor is located near the tray such as above or below the tray. Therefore, the state of the sheet on the tray can be detected by the sensor at that time. That is,
Even if the number of trays increases, only one sensor needs to be used.

[0020]

1 to 9 show an embodiment of a sheet stacking apparatus according to the present invention. In this example, an example in which the stapler mechanism is applied to a device in which the stapler mechanism is mounted is adopted, and a stapler movable type in which the stapler slides is adopted. That is, in the present embodiment, there are provided elevating means for elevating or lowering a tray for placing sheets to a predetermined position (sheet discharging position), and sliding means for sliding the stapler laterally toward the tray at a predetermined position. Assuming a sheet stacking device, such a device is provided with alignment means.

Here, the elevating means and the sliding means will be described first. As shown in FIG. 1 and FIG.
The camshafts 2a and 2b are vertically disposed on both sides of the inside. The two camshafts 2a and 2b are connected at a lower portion thereof by a power transmission mechanism such as a timing belt, a gear mechanism, and a rotating shaft (not shown), and the two shafts 2a and 2b rotate at the same speed in synchronization. It is designed to be driven. Then, the rotation output of the drive motor is given to the power transmission mechanism, and by rotating a single drive motor, the cam shafts 2a and 2b are rotated. A large number of trays 3 are provided between the two camshafts 2a and 2b so as to be able to move up and down in a stacked state.

In addition, cylindrical groove cams 4a and 4b are fixed to an intermediate portion between the two cam shafts 2a and 2b, respectively.
More specifically, the cylindrical groove cams 4a and 4b are positioned at the height of the sheet discharge port of the copying machine. Further, follower rods 5a and 5b are fixed to both side surfaces of the tray 3 in a state of protruding horizontally. The distal ends of the follower rods 5a and 5b are formed in a smooth hemispherical shape, and the distal ends of the follower rods 5a and 5b are
a and 4b are fitted in the cam grooves 4a 'and 4b', and move smoothly along the cam grooves.

That is, the tips of the driven body rods 5a and 5b projecting from both side surfaces of the tray 3 are fitted into the cam grooves 4a 'and 4b' of the two cylindrical groove cams 4a and 4b, respectively. 4b, the tray 3 attached to the driven body rods 5a and 5b is rotated.
It moves up and down according to the spiral cam grooves 4a 'and 4b'. The cam grooves 4a 'and 4b' are formed in the cylindrical groove cams 4a and 4b so as to make two rounds on the side surface. When the cylindrical groove cams 4a and 4b make one round, the tray 3 moves up and down one step. ing. Moreover, in the present embodiment, the pitch (lead) of the cam grooves 4a 'and 4b' is set to be unequal, so that the interval D between the tray 3 located at the sheet discharge port and the tray above it is greatly increased. Has become. Thus, a predetermined number of the discharged sheets 6 are stacked without being jammed. In addition, the tray 3 concerned
Since the mechanism for moving up and down is known, detailed description thereof is omitted.

In this embodiment, as shown in the developed view of FIG. 3, the cam grooves 4a 'and 4b' are formed such that a half rotation of one rotation is an inclined area and the remaining half rotation is a horizontal area.
As a result, when reference is made to 0 degree, 180 degrees
Follower rods 5a, 5a
When b is moving, the tray 3 also moves up and down, and 1
When the follower rods 5a and 5b are moving in a horizontal region from 80 degrees to 360 degrees, the tray 3 does not move in the height direction and is in a stationary state.

In the stationary state, the staple unit 7 moves horizontally. In other words, after the sheet bundle is advanced toward the sheet 3 side, the end of the sheet bundle on which the predetermined number of sheets 6 are stacked is stapled, then the sheet bundle is moved backward and returned to the standby position. In this example, the staple unit 7 is driven using a power transmission mechanism as described below as a mechanism for moving the staple unit 7.

As shown in FIGS. 4 and 5 in an enlarged manner, first,
The staple unit 7 includes a stapler portion that staples a sheet 3 by hitting a staple and stops the stapler, and a control device that controls an opening / closing operation (staple stop) of the stapler. The staple unit 7 is installed on a slide base 11 arranged close to one camshaft 2a. The slide base 11 is mounted on two guide rods 12, 12 and can reciprocate along the guide rods 12.

A cam floor 14 is attached to the lower surface of the slide base 11.
Correspond to the cam groove 19 a of the eccentric cam 19 installed below the slide table 11. The cam groove 19a of the eccentric cam 19 has a small arc portion having a small radius concentric with the rotation center P (the left half area in FIG. 5).
And a large arc portion having a large radius eccentric from the rotation center P (the right half area in FIG. 5).

Accordingly, when the eccentric cam 19 rotates, the distance from the rotation center P is constant and short while it coincides with the small arc portion of the cam groove 19a, so that the staple unit 7 as shown in FIG. Is located at a standby position away from the tray 3 (sheet 5) and stands still in that state. When the rotation further coincides with the large arc portion of the cam groove 19a, the diameter is large and eccentric from the rotation center P, so that the distance from the rotation center P becomes longer as the rotation proceeds, so that the slide table 11 Consequently, the staple unit 7 moves forward toward the tray 3. Then, when the robot advances to half of the large arc portion, it advances most (see FIGS. 1 and 5). Thereafter, the distance between the large arc portion and the rotation center P gradually decreases, so that the staple unit 7 also moves backward. Works.

Further, pulleys 20 are provided at the lower end of the eccentric cam 19 and the lower end of the cam shaft 2a, respectively, and a timing belt 21 is stretched between the pulleys 20. As a result, when a drive motor (not shown) is rotated, the cam shafts 2a and 2b rotate to move the tray 3 up and down as described above. In synchronization with this rotation, the eccentric cam 19 also rotates and the staple unit 7 is rotated. Is reciprocated (forward-backward movement). That is, the raising and lowering of the tray 3 and the reciprocating movement of the staple unit 7 are operated based on a single drive source.

Then, the correlation between the two movements (the staple unit 7 reciprocates while the tray 3 is stopped, and the staple unit 7 is at the standby position while the tray 3 is moving up and down).
Eccentric cam 19 during one rotation of the camshaft 2a.
Also makes one rotation. In addition, while the follower rod 5a of the tray 3 coincides with the inclined region from the reference position (0 degree shown in FIG. 3) of the cam shaft 2a to 180 degrees, the cam floor 14 is in the cam groove 19a of the eccentric cam 19. The cam floor 14 is aligned with the large arc portion of the cam groove 19a of the eccentric cam 19 while the follower rod 5a of the tray 3 is aligned with the horizontal area. Set.

Further, in order to detect the reference phase point of the drive mechanism, an index cam 17 is fixed to the lower end of one cam shaft 2a, and a sensor 18 is provided opposite to the index cam 17 (FIG. 1). 4). The groove (not shown) of the index cam 17 is
8, a detection signal is output from the sensor 18. Specifically, when the predetermined tray 3 comes to the installation position of the staple unit 7, that is, the discharge position of the sheet 6, and when the staple unit 7 comes to the forefront position (the state of FIGS. 1 and 5). The detection signal is turned on. When the detection signal is turned on, the angular position shown in FIG. 3 is 270 degrees.

The detection signal is sent to the staple unit 7 (a built-in control device). The stapling unit 7 is also adapted to receive a staple command signal (a signal of a command to stop the stapling when a predetermined number of sheets have been discharged) from the copying machine body. Then, when both the stapling command signal from the copying machine main body and the detection signal from the sensor 18 are turned on, stapling is stopped.

The staple command signal from the copier body and the detection signal from the sensor 18 are also sent to a driver for controlling the rotation of the drive motor for rotating each cam. Is to be paused. This allows the staple unit 7 to perform the stapling process when the operation is temporarily stopped.

As described above, in this embodiment, the elevating means and the sliding means are operated based on the rotational force of one drive motor, so that the stapler is horizontally slid at a predetermined timing in accordance with the elevating movement of the tray. This makes the mechanical configuration extremely simple and facilitates miniaturization of the device.

Further, in this embodiment, the cylindrical groove cams 4a, 4e, which move the tray 3 up and down based on the output of one drive motor,
4b and the rotation drive of the eccentric cam for moving the staple unit 7 forward and backward.
When the tray 3 is moved up and down, the staple unit 7 is in a stationary state, so that only a load required for moving the tray 3 up and down is applied to the drive motor. Conversely, when the staple unit 7 is moved forward and backward, the tray 3 is in a stationary state, so that only a load necessary for moving the staple unit 7 is applied to the drive motor. That is, since the staple unit 7 and the tray 3 do not move at the same time, even if two types of members are driven by one drive motor, the load is not so large, and the capacity is almost the same as that of the conventional drive motor. I'm done.

In this embodiment, the drive source of the slide means for moving the staple unit is shared with the lifting means for the tray as described above. However, the present invention is not limited to this. Of course, a device that operates with another driving source generally used in the related art may be used.

Next, a description will be given of the matching means which is a main part of the present invention. As shown in FIGS. 1 and 2, the alignment means is provided on the side opposite to the side on which the staple unit 7 is installed. In addition, as a specific structure, a motor 2 such as a stepping motor or the like,
6 is attached. The gear 26 a fixed to the output shaft of the motor 26 is meshed with the gear 27 a fixed to one end of the screw 27, so that the torque of the motor 26 can be transmitted to the screw 27. The screw screw 27 is arranged so as to extend in parallel along the side edge of the tray 3 facing the sheet discharge side, and is provided with an alignment bar 28 for urging the screw screw 27 against the side edge of the sheet 6. Connected.

One end of the alignment bar 28 is connected to the screw screw 27, and the support rod 28a has a rectangular parallelepiped shape and moves forward and backward (slides) according to the forward and reverse rotation of the screw screw 27, and the tip of the support rod 28a. And an operating rod 28b fixed to the lower surface of the actuator. Then, the operating rod 28b is moved to the sheet 6 actually stacked on the tray 3.
Abuts against the side edge of the rim to urge it. And
The alignment bar 28 moves within a rectangular cutout 3 a formed in the tray 3. The notch 3a is formed at a position where the side edge of the sheet 6 discharged onto the tray 3 is located. Further, as shown in FIG. 2, the operating rod 28b is set to a length that does not contact the tray located below the tray on which the sheet to be subjected to the alignment process is placed.

A sheet presence / absence detection sensor 29 is mounted on the side of the tip of the support rod 28a on the tray side.
Further, a sheet full load detection sensor 30 is attached to the center of the tray-side measurement surface of the support rod 28a. These sensors 29 and 30 are integrated with the alignment bar 28 (actuation rod 28 b) and simultaneously move forward and backward toward the seat 6. Further, a protrusion 32 is provided on the end face of the support rod 28 on the base end side (the screw screw 27 side).
When the alignment bar 28 is at the home position as shown in FIG. 7, the projection 32 faces the home position (HP) sensor 31 and the HP
The projection 32 is detected by the sensor 31 and a detection signal is output.

The sheet presence / absence detection sensor 29 detects whether or not there is at least one sheet 6 on the tray 3 and can be realized by, for example, a reflection type optical sensor or the like. Then, based on the output of the sensor 29, for example, the control of turning on / off the display lamp 38 installed on the side surface of the case 1 shown in FIG. 6 can be performed. That is, when the sensor is ON, the corresponding display lamp 38 is turned on. This makes it possible to see at a glance which tray 3 the sheet is on from the side.

The full-sheet detecting sensor 30 detects whether or not a predetermined number of sheets 3 (actually, a predetermined height or more) are stacked on the tray 3 and can be realized by a limit switch. That is, as shown in FIG. 2, the tip of the detection lever 30a protrudes from the lower surface of the sensor 30. The tip of the detection lever 30a comes into contact with the sheet 3. When a predetermined number of sheets 3 are stacked, the tip of the detection lever 30a is pushed up and the switch is turned ON. This makes it possible to stop sheet discharge before a paper jam occurs, thereby preventing the printer from going down.

Further, the HP sensor 31 is
Is detected to return to the home position (standby position), and can be realized by a proximity sensor or the like. Thus, after confirming that the alignment bar 28 is at the home position, by controlling the tray 3 to move up and down, interference between the tray 3 and the alignment bar 28 can be prevented. Of course, it does not interfere with the sheet 6 and the alignment bar 28.

Then, each of the sensors 29, 30, 3
1 sends each sensor output to the CPU 40 as shown in FIG. Further, the CPU 40 is provided with a paper size, a stapler operation command, a tray number to be used, and other information from the printer main body 42. Then, the CPU 40 determines the RO based on the information given from the sensor and the printer main body 42 and the like.
A predetermined matching process is performed according to the program registered in M43. In the example shown in FIG. 8, the output of the CPU 40 is connected to the driver for driving the motor 26 for moving the alignment bar 28 and the display lamp 38, but the tray 3 and the staple unit 7 are further moved although not shown. And a control signal to the staple unit 7 for the drive motor.

The function of the CPU 40 relating to the matching process is, for example, as shown in the flowchart of FIG. That is, after receiving the detection signal from the HP sensor 31 and confirming that the alignment bar 28 has returned to the home position, the tray is moved up and down to move a predetermined tray to a sheet (paper) discharge position, and A discharge process is performed (ST1, ST2).

Then, the paper size of the sheet currently being discharged is acquired, and the moving distance of the alignment bar (the operating rod 28 of the alignment bar) is obtained.
The distance between b and the side edge of the sheet 6 on the tray 3 is determined (ST3). Actually, since the paper size is predetermined in several types, instead of calculating each time, the distance (the number of rotations of the motor 26) corresponding to the paper size is stored as a table and read out. Can respond.

Then, based on the sheet size, the motor 26 is rotated forward by a predetermined amount, and the alignment bar 28 is moved to the sheet 6.
(ST4). Then, the operating rod 28b of the alignment bar 28 contacts the side edge of the sheet 6 and urges it. Therefore, the sheet bundle discharged onto the tray 3 is urged to the opposite side, and if the opposite side edge is separated from the side wall 3b serving as the locking portion of the tray 3, the sheet bundle is 3 until it hits the side wall 3b, and hits the side wall 3b to be aligned (ST5). At least when the sheet alignment processing is being performed, the sheet detection sensor 29 is turned ON, and the display lamp 38 of the number of the tray 3 being processed is turned on (ST6).

When the alignment bar 28 is moved to a predetermined position, the rotation of the motor is temporarily stopped, and the state is maintained for a certain period of time. Then, after a lapse of a predetermined time, it is determined that the alignment is completed (ST7), and the flow proceeds to step 8 where the full sensor 30
, And it is determined whether or not a predetermined amount or more of sheets are stacked on the tray 3 (ST8). If it is not full, the motor 26 is rotated in reverse to return the alignment bar 28 to the home position in preparation for discharging the next sheet to the same tray (ST9). The reverse rotation is performed until the HP sensor 31 detects the protrusion 32. Then, the process returns to step 21 to discharge the next sheet, and then performs the alignment process.

On the other hand, if it is determined in step 8 that the tray is full, the process jumps to step 10, the motor 26 is rotated in the reverse direction to return the alignment bar 28 to the home position (ST10), and then the tray is raised and lowered. It moves and positions an unused (no sheet loaded) empty tray in the sheet discharge section (ST11). Then, the alignment bar is moved forward by rotating the motor 26 forward in the same manner as described above, and the alignment process is performed by urging the side edges of the sheet. Then, when the matching process is completed (stop for a certain period of time), the process returns to step 8 to determine whether or not it is full. Thereafter, by repeatedly performing such processing, the set number of sheets can be discharged to the tray without paper jam, and the sheet bundle stacked on each tray is in a state where the side edges are arranged.

After the alignment process, a staple process is performed as needed. In some cases, only the alignment process is performed without performing the stapling process. The usage mode is determined according to an instruction from the operator.

In the above-described embodiment, only the application of the sorter mechanism with the stapler of the printer has been described. However, the present invention is not limited to this, and may be applied to a sorter mechanism of a copying machine or another sheet sorting machine. Needless to say, the sheet stacking apparatus of the present invention can be applied to anything.

[0051]

As described above in detail, according to the present invention, the alignment bar can slide laterally in the cutout portion provided in the tray without interfering with the tray other than the tray to be processed. Even if sheets of different sizes are discharged, the sheets on each tray can be aligned. Further, according to the third aspect, sheets can be discharged onto a predetermined tray without causing a paper jam or the like. In addition, with the configuration according to the fourth aspect, the number of sensors to be installed can be reduced, and the number of components is small and the configuration is simple.

[Brief description of the drawings]

FIG. 1 is a plan view showing a state of a staple advance position of an embodiment of a sheet stacking apparatus according to the present invention.

FIG. 2 is a side sectional view of the same device in FIG.

FIG. 3 is a diagram illustrating a cam groove of a cylindrical groove cam used in the apparatus.

FIG. 4 shows a mechanism for raising and lowering a tray including a cylindrical groove cam;
FIG. 4 is a diagram illustrating a mechanism for sliding a stapler.

FIG. 5 is an enlarged view of a main part of FIG. 1;

FIG. 6 is a diagram showing an appearance of the device.

FIG. 7 is a plan view showing the staple standby position of the apparatus.

FIG. 8 is a block diagram showing a sensor mounted on the device and a signal processing circuit of the sensor output.

FIG. 9 is a flowchart illustrating functions related to a matching process of a CPU.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Body cover 2a, 2b Cam shaft (elevation means) 3 Tray 3a Notch part 3b Side wall (locking part) 4 Cylindrical groove cam (elevation means) 4a, 4b Cylindrical groove cam (elevation means) 4a ', 4b' Cam groove ( Elevating means 5a, 5b Follower rod (elevating means) 6 Sheet 7 Staple unit 11 Slide base (slide means) 12 Guide shaft (slide means) 14 Cam floor (slide means) 19 Eccentric cam (slide means) 19a Cam groove (slide) Means) 20 Pulley 21 Timing belt 26 Motor 27 Screw screw 28 Alignment bar 29 Sheet detection sensor 30 Sheet full detection sensor Inclined area Horizontal area

Claims (4)

[Claims] 1. A sheet stacking device for lowering or raising a tray for mounting sheets to a predetermined position, wherein a locking portion for positioning is provided on one side edge of the tray, and the locking portion is provided with a locking portion. A notch is provided at a side edge of the tray on the opposite side, an alignment bar is provided so that the inside of the notch provided in the tray at the predetermined position can be slid horizontally, and the alignment bar is a target to be processed by sliding horizontally. It comes into contact with the side edge of the sheet on the tray and urges the locking portion side, and furthermore, the alignment bar, when slid laterally, with a tray other than the tray to be processed. The sheet stacking apparatus is set in such a size that it does not contact, and is set so that the alignment bar does not interfere with the tray when the tray is moved up and down. 2. The sheet stacking apparatus according to claim 1, further comprising a staple unit for stapling an end of the bundle of sheets stacked on the tray to be processed. . 3. The apparatus according to claim 1, further comprising a sensor for detecting whether a tray for receiving the discharged sheets is in a full load state, and performing a discharging process on the stackable trays. A sheet stacking apparatus according to claim 1. 4. The sheet stacking apparatus according to claim 1, wherein a sensor for detecting a state of a sheet on a tray is attached to the alignment bar.