JPH0558530A - Sheet stacking device - Google Patents

Abstract

PURPOSE:To provide a sheet stacking device which orderly stacks cut sheets carried by a conveyor into a stacking. CONSTITUTION:Cut sheets 25 carried by a conveyor 20 are clamped by means of a clasp device 30, slowed down and fed into a stacking 16. When the quantity of the sheets to be stacked in the stacking reaches the specified value, an supplementary fork is inserted, and the stacking is rapidly lowered, and at the same time, a main fork is inserted. The supplementary fork is drawn out and another stacking is set while cut sheets are stacked on the main fork.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the field of cutting corrugated board, paper, plastic, iron, aluminum, copper and foil materials, and clamps the rear end of the sheet while running the sheet cut by a cutting machine. Then, the present invention relates to a sheet stacking device for reducing the traveling speed of sheets to an optimum speed necessary for stacking the traveling speed of the sheets on the stacking (stacking unit) in order and stacking the sheets in the orderly and directly on the stacking.

[0002]

2. Description of the Related Art Conventionally, in order to stack sheets cut by a cutting machine on a wide variety of materials such as corrugated cardboard, paper, plastic and foil, the sheets are conveyed by a high-speed conveyor, and the speed difference from the high-speed conveyor is increased. The traveling speed of the sheet was reduced by an overlap conveyor (low-speed conveyor) having a. Then, the sheets decelerated by the overlap conveyer are sequentially overlapped and conveyed on the overlap conveyer, and the sheets are stacked in the layboy section for each laminated lot.

There are various types of overlap conveyors. For example, a sheet conveyed from a high speed conveyor is softly caught by a "holding whisker" or "air vacuum" on the low speed conveyor to travel the sheet. The sheets are conveyed by overlapping the sheets in an overlapping manner by reducing the speed, or the sheets conveyed from the high-speed conveyor are handled by the "catching belt", "pressing belt", "low-speed conveyor", etc. Soft catches were performed, the traveling speed of the seats was reduced, and the traveling seats were overlapped and conveyed in an overlapping manner.

In any case, in such an overlap conveyor system, since there is a speed difference between the preceding high-speed conveyor and the overlap conveyor, sheets traveling at high speed are constructed as the overlap conveyor. Due to friction such as “holding whiskers”, “catching belts”, or “holding belts” on the surface of the sheet, the leading edge of the sheet may be broken or scratched for transport from the high-speed conveyor, With a weak sheet, the leading edge of the sheet hangs down or bumps against the preceding sheet, causing many problems such as saying that the sheet cannot be fed normally.

As a means for solving such a problem, Japanese Unexamined Patent Publication No. 60-137763 discloses "a device for decelerating a continuously flowing cutting sheet". As shown in FIG. 11, this apparatus includes a speed reducer including a brush roll 103 and a low speed rotation roll 104 between a conveyor 101 and a stacking 102. Roll 10
3, 104 are motors 1 via a suitable gear device 105
It is driven by 06.

In this prior art, when the sheet 107 continuously passes between the two rolls, one brush 108 comes into contact with a portion near the trailing edge of the sheet 107 and presses the sheet against the roll 104 rotating at a low speed to decelerate the sheet. , To the stacking 102. However, in such a brush roll 103, the sheet is brushed to the roll 1 and the roll 1
There is a risk that the operation of pressing the sheet against 04 is unstable, and if the sheet is paper, the brush may damage the paper. Further, since the sheet pressing position is not accurately controlled, the sheet pressing position may be displaced, making it impossible to stack the sheets orderly on the stacking.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems of the prior art, the applicant of the present invention filed Japanese Patent Application No. 2-2831.
In No. 78 “Sheet Stacking Device”, the standard position of the rear end of the sheet is accurately clamped while the sheet is traveling, and the traveling speed of the sheet is reduced to the optimum speed necessary for stacking the sheets in stacking orderly. The sheet stacking device using the clamping means is proposed.

However, the sheet stacking apparatus according to this proposal has a drawback that the structure becomes complicated because two stacking must be prepared.

An object of the present invention is to provide a sheet stacking device which can solve many of the problems mentioned above.

[0010]

A sheet stacking apparatus of the present invention is a sheet stacking apparatus for stacking sheets cut and run by a cutting machine on a stacking machine, and cut sheets cut by the cutting machine at predetermined sheet intervals. A conveyor that conveys while holding the sheet, and a clamping device that clamps the reference position of the rear end of the sheet during conveyance, and reduces the traveling speed of the sheet to the optimum speed necessary for stacking the sheets in stacking orderly, A lifter that raises and lowers the stacking, an auxiliary fork that is inserted into the stacking when the number of sheets stacked in the stacking reaches a predetermined number, and a main fork that is inserted into the stacking at the same time when the lifter descends after the auxiliary fork is inserted. And a servomotor that drives the clamp device, and A servo amplifier for controlling the motor,
A position detector that detects the trailing end position of the sheet being conveyed on the conveyor, a first encoder that detects the speed of the conveyor, and a second encoder that detects the rotation speed of the servo motor.
Encoder, an origin detector that detects the origin of the clamp device, a phase setting device that sets the reference position, an output of the first encoder, an output of the second encoder, and the origin detector. A first control circuit that performs phase velocity tuning control of the clamp device based on the output of the position detector, the output of the position detector, and the output of the phase setting device,
It has a 2nd control circuit which performs the top dead center positioning control of the said clamp device based on the output of the said 2nd encoder and the output of the said origin detector.

[0011]

[Operation] A sheet that is cut at a high speed by a sheet cutter and runs is clamped at a fixed position of the trailing end of the running sheet after cutting, regardless of the sheet cutting length, by a clamp device to reduce the running speed to an optimum speed. , Stack sheets directly on the stack in a layboy machine without overlapping.

When the number of sheets stacked in the stacking reaches a predetermined number, the auxiliary fork and then the main fork are inserted, and the sheets are stacked on the main fork until a new stacking is prepared. The preparation period is long,
When the number of sheets stacked on the main fork is large, the main fork is lowered.

[0013]

FIG. 1 shows an embodiment of the present invention. As shown in FIG. 1, the sheet stacking apparatus includes a cutting machine 1, a sheet conveying conveyor 20, a clamp device 30 that clamps a rear end portion of a cut sheet 25, and a layboy device 40 that sequentially stacks the cut sheets. It The cutting machine 1 includes sheet cutters 1a and 1b, and cuts materials such as cardboard, paper, plastic, and foil into predetermined lengths by the sheet cutters. The sheet conveying conveyer 20 is provided after the cutting machine 1, and in order to convey the cut sheet without slipping, meandering, etc., the sheet conveyer 2 for moving the cut sheet to the lower stage and the sheet conveyer to the upper stage. It has a sheet pressing conveyer 3 for pressing and transporting the sheet.
Is provided.

The pressing belt 5 of the sheet pressing conveyor 3 is composed of several belts, and forms a loop from the sheet pressing conveyor 3 through the clamp device 30 and the layboy device 40 and back to the sheet pressing conveyor 3. ing. The seat pressing belt 5 is a Rayboy device 40.
Above, it also serves as the sheet guide belt 18 for stacking the cut sheets accurately. Further, a sheet detector 6 for detecting the reference position of the trailing end portion of the sheet and synchronizing with the clamp device 30 is provided above the sheet conveying conveyor 20.

The speed of the sheet conveying conveyor 20 is set to be several to ten and several percent higher than the line speed in order to uniformly widen the interval between the cut sheets.

The clamp device 30 is a device for clamping the rear end portion of the cut sheet, and is composed of an upper rotating device 31 and a lower speed reducing roll 10.

The rotating device 31 is composed of a rotating mechanism portion 8 and a free roll 9 which is supported by an arm in parallel with the rotating shaft of the rotating mechanism portion. The rotating device 31 is driven via the speed change mechanism unit 7, cuts the free roller 9 and presses the rear end of the sheet, and the belt gap between the deceleration rolls 1.
The sheet is pressure-bonded to 0, that is, clamped, the speed of the cut sheet is reduced to the same speed as that of the deceleration roll 10, and the cut sheet is sent to the rayboy device 40.

The deceleration roll 10 comprises a plurality of (four in the figure) non-slip rolls 2 provided on the shaft 26 at regular intervals.
Equipped with 7. The deceleration roll 10 is rotated by the speed change mechanism unit 28, and its rotation speed is set according to the sheet material, the line speed, and the sheet cutting length.

An auxiliary fork 11 which is horizontally reciprocally driven is provided between the speed reducing roll 10 and the sheet conveyor 2, and this auxiliary fork is provided between the non-slip rolls 27 of the speed reducing roll 10 as shown in FIG. After that, the stacking 16 of the rayboy device 40 can be ejected.

Further, below the sheet conveyor 2, there is provided a main fork 12 which is horizontally reciprocally driven and is capable of moving up and down. This auxiliary fork is, as shown in FIG.
It is configured such that it can protrude to the stacking 16 of the layboy device 40 through the non-slip roll 27 of the deceleration roll 10.

As described above, the auxiliary fork 1 horizontally reciprocally driven between the deceleration roll 10 and the sheet conveyor 2.
1, the distance between the deceleration roll 10 and the sheet conveyor 2 becomes long. Therefore, in order to prevent the cutting sheet 25 from sagging downward, an air blowing table 29 for blowing air upward is provided above the auxiliary fork 11.

The rayboy device comprises the above-mentioned stacking 16, a lift 17 for raising and lowering the stacking,
The stopper 14 that receives the leading edge of the cut sheets 25 that are input to the stacking, the jogger 35 that aligns the rear ends of the cut sheets that are input to the stacking, and the side jogger 15 that aligns the side edges of the cut sheets are provided.

The jogger 35 has a structure in which a vertical plate is horizontally reciprocally driven between the non-slip rolls 27 of the speed reduction roll 10. The vertical plate has a hole through which the auxiliary fork 11 can pass and the main fork 12. A recess is provided therethrough. A part of the jogger 35 is shown in FIG.

Next, the schematic operation of the sheet stacking apparatus having the above-mentioned structure will be described with reference to FIGS.

The rotating device 31 of the clamp device 30 starts tracking at the time when the sheet detector 6 of the sheet conveying conveyor 2 detects the rear end position of the cut sheet 25. Then, the free roller 9 of the rotating device 31 is speed-tuned at a fixed position preset from the rear end reference of the cut sheet 25, and the free roller 9 of the rotating device 31 is decelerated by the deceleration roll 10 via the space between the pressing belts 5. Clamp the cutting sheet by crimping the cutting sheet to. Then, the cut sheet traveling from the sheet conveying conveyor 20 is clamped at the rear end portion of the cut sheet by the free roller 9 and the deceleration roll 10 of the rotating device 31 so that the cut sheet has an optimum speed (of line speed). After being decelerated to 10% to several 10%), it is sent to the stacking 16 along the lower surface of the sheet guide belt 18, and the cut sheet is stopped by the stopper 14 of the stacking 16 as shown in FIG. Stacked.

The sheets stacked on the stacking 16 align the rear end faces of the cut sheets each time the free roller 9 and the reduction roller 10 are clamped by the jogger 13. Similarly, the side jogger 15 is opened and closed for every certain number of cut sheets, the end faces on both sides of the cut sheets are aligned, aligned properly, and stacked in order. Then, the lifting / lowering lift 17 is automatically lowered intermittently by a seat top surface detector (not shown) so that the top surface of the seat is always at a fixed position. The ascending / descending lift 17 finally stops at the descending limit.

When the cut sheets stacked in the stacking 16 in the correct order are stacked in the stacking 16 in a set number of sheets, the auxiliary fork 11 simultaneously causes the non-slip of the deceleration roll 10 by the skid change or order change signal as shown in FIG. Cut sheets 25 stacked between the rolls 27 and stacked on the stacking 16
Inserted into the upper surface of the auxiliary fork 11
Are stacked on top of each other. And as shown in FIG.
At the same time when the cut sheets stacked on the stacking 16 start to descend, the main fork 12 is inserted through between the non-slip rolls 27 of the speed reduction roll 10, and when the insertion is completed, the auxiliary fork 11 is removed. Then, the cut sheets 25 are stacked on the main fork 12.

The cut sheets stacked on the stacking 16 are lowered by the lift 17 and stopped at the lower limit. Then, the cut sheets stacked on the stacking 16 are carried out, and a new stacking 16 is carried in,
When the carrying-in is completed, the stacking 16 is lifted to the position of the main fork 12 by the lift 17 and stopped. If the time required for skid change or order change is long and the number of cut sheets piled up on the main fork 12 is large during this time, the main fork 12 may be lowered.

When the lift 17 stops, the main fork 12
The cut sheets that have been pulled out and stacked on the main fork 12 are re-stacked on the stacking 16. And
The sheets stacked on the stacking 16 are aligned by aligning the rear end surfaces of the sheets by the jogger 35, and similarly, the side joggers 15 are opened and closed for each certain number of sheets, aligning the end surfaces on both sides of the sheet, and aligning properly. Stacked one after another. Then, the stacked lifted sheets 17 are automatically lowered by the sheet upper surface detector so that the upper surfaces of the sheets are always at a fixed position. The ascending / descending lift 17 finally stops at the descending limit.

Next, the control system of the sheet stacking apparatus of this embodiment will be described with reference to FIG. 6 is shown in FIG.
3 shows a control system for the sheet conveying conveyor 20, the clamp device 30, and the layboy device 40 of FIG.
There are two controls: phase velocity tuning control and top dead center positioning control.
Parted on the street.

The phase-velocity synchronization control is to control the free roller 9 of the clamp device 30 to touch the deceleration roll 10 at a position semi-fixed from the trailing edge of the sheet in synchronization with the sheet flow velocity. The speed tuning is the sheet conveyor 2
The frequency of the pulse generated from the pulse generator (PG) 50 attached to the is converted into voltage by the frequency / voltage (F / V) converter 52 to detect the line speed, and the speed command B from the speed command selection circuit 54 is detected. Is input to the servo amplifier 57 of the AC servo motor 56 that drives the clamp device 30. On the other hand, phase control
A value (L−X) obtained by subtracting the distance X of the clamp position from the rear end reference of the cutting sheet 25 from the distance L from the bottom dead center of the rotating device 31 to the sheet detection sensor 6 is preset in the phase setting device 58. This is the phase setting. This phase setting is based on the deceleration position signal A (a signal indicating the deceleration start position at 90 ° from the bottom dead center of the rotating device) obtained from the origin detected by the origin sensor 60 provided near the rotating device 31. , To position deviation counter 64 (L-X)
-B ₀ is converted into a pulse and set. B
₀ is the circumference of the rotating device 31. The sheet flow length is such that when the sheet detection sensor 6 detects the trailing edge of the cut sheet (C signal), the gate 66 is opened, the pulse of the pulse generator 50 is input to the deviation counter 64 by subtraction, and the gate 66 is generated by the signal A. Close. The deviation counter 64 is decremented by the sheet flow length pulse AA, and when the rotating device 31 reaches a position where acceleration synchronization can be achieved with the target clamp position, the rotating device starts acceleration, and the decelerating roll 10 sandwiches the cut sheet 25.
Prior to contact with, the speed is tuned by the speed tuning function described above, and at the same time, the phase is adjusted by the following arithmetic expression. A pulse generator (PG) 6 attached to the rotating device driving AC servomotor 56 with the value of the position deviation counter 64 as R
When the value obtained by counting the 8 pulses is BB (count reference deceleration start point), R is represented by the following equation.

R = ((L−X) −B ₀ ) −AA + BB This calculation is performed in the adder / subtractor 76, and the deviation counter 64 holds the value of R. R is a D / A converter 78
Is converted into an analog signal V _C by the adder / subtractor 80 to calculate a speed command ( _VA −V _C ).

In the above equation, R is finally zero because the purpose of the control is to make the deviation zero. Where B
Since the value of B finally corresponds to one rotation of the rotating device, BB = B ₀ . Therefore, by this and R = 0, AA = (L−X), and AA, that is, the clamp position can be set to the position X from the rear end of the sheet.

The top dead center positioning control means the cutting sheet 25.
This is a necessary function because it is necessary to make the rotating device 31 stand by at the top dead center until the sheet comes when the sheet does not come continuously. With the deceleration position signal A, the top dead center position deviation counter 7
Set the length l to the top dead center to 0 (see Fig. 7),
Counts down with the pulse of the pulse generator 68,
The speed command V _B is created via the D / A converter 72 and the speed command clamp circuit 74. Positioning is performed at count zero, and the free roller 9 is stopped at the top dead center.

The speed command for the phase speed synchronization control described above (V _A -V _C), the speed command V _B for the top dead center positioning control, speed command selecting circuit (higher voltage selecting circuit) 54
Is input to the servo amplifier 57 as a speed command B.

The speed pattern of the clamp device becomes three patterns 1, 2, and 3 shown in FIG. 8 depending on the sheet interval.

Pattern 1 shows the long mode, that is, the case where the sheet interval is long. When the sensor 6 detects the trailing edge of the sheet at time t _1, accelerated with (V _A -V _C) rate of up to time t ₃ to speed tuned at time t ₂ reaches the velocity V _B retains this speed. At time t ₃ , the X position is clamped from the rear end of the sheet, the sheet speed is reduced, and the sheet 62 is sent to the stacking 16. It reaches the top dead center at time t ₄ , and stops at the top dead center until time t _{5 at} which the trailing edge of the next sheet is detected.

Pattern 2 shows the case where the next sheet comes while in the medium-size mode, that is, before stopping at the top dead center. In this case, clamp at time t ₆ , start decelerating,
The vehicle is accelerated again at time t ₇ without stopping at top dead center.

Pattern 3 shows the short mode, that is, the sheet interval is shorter than the setting (L-X). In this case, it is clamped at time t ₈ , starts decelerating, and is held at a constant speed at time t ₉ .

FIG. 9 is a diagram showing another embodiment of the present invention. In this embodiment, the deceleration roll 10 in the embodiment of FIG.
Instead of the above, a deceleration table 90 for horizontal reciprocating drive is used. This deceleration table 90 is used for stacking 1
It also has the function of a jogger that aligns the rear ends of the cut sheets 25 stacked on each other, and the free roller 9 and the deceleration table 90.
Every time the cut sheets are clamped by, the rear end surfaces of the sheets that have been previously conveyed and stacked on the stacking 16 are aligned by the jogger 91. As shown in FIG. 10, the jogger 91 is provided with a hole 92 and a recess 93 through which the auxiliary fork 11 and the main fork 12 pass.

In the present embodiment, the clamp device 30 starts tracking at the time when the sheet detector 6 of the sheet conveyor 2 detects the trailing end position of the cut sheet. Then, the clamp device 30 synchronizes with the speed at a preset fixed position from the trailing end reference of the cut sheet, and the free roller 9 of the rotating device 31 mechanically works with the deceleration table 90 through the space between the pressing belts 5. While synchronizing, the free roller 9 of the rotation device 31 presses the sheet at the reference position of the deceleration table 90 and clamps the sheet. Then, the traveling sheet from the sheet conveying conveyor 20 is decelerated to the optimum speed by clamping the rear end portion of the cutting sheet from the free roller 9 of the rotation device 31 and the deceleration table 90, The sheet is fed to the stacking 16 along the lower surface of the sheet guide belt 18, and the cut sheet is crushed by the stopper 14 of the stacking 16 as shown in
They are stopped and stacked one by one on stacking.

The sheets stacked on the stacking 16 are aligned by the jogger 91 which is also used as the clamp table 90 and the rear end surfaces of the sheets are aligned each time the free roller 9 and the deceleration table 10 are clamped. Similarly, the side jogger 15 is opened and closed for every certain number of sheets, the end faces on both sides of the sheets are aligned, aligned properly, and stacked in sequence. Then, the lifting / lowering lift 17 is automatically lowered intermittently by a seat top surface detector (not shown) so that the top surface of the seat is always at a fixed position. Lifting lift 17
Finally stops at the descent.

When the cut sheets stacked in the stacking 16 in the correct order are stacked in the stacking 16 in a set number of sheets, the auxiliary fork 11 is simultaneously stacked by the auxiliary fork 11 by a skid change or order change signal.
The cutting sheets are stacked on top of each other and the next cutting sheets are sequentially stacked on the auxiliary fork 11. The cut sheets stacked on the stacking 16 start to descend, and at the same time, the main fork 12 is inserted, and when the insertion is completed, the auxiliary fork 11 is removed.

The cut sheets stacked on the stacking 16 are lowered by the lift 17 and stopped at the lower limit. Then, the cut sheets stacked on the stacking 16 are carried out, and a new stacking 16 is carried in,
When the carry-in is completed, the stacking 16 is lifted to the position of the main fork 12 by the lifting lift 17 and stopped, the main fork 12 is removed, and the cut sheets stacked on the main fork 12 are re-stacked on the stacking 16. The sheets stacked on the stacking 16 are aligned with the rear end surfaces of the sheets by the jogger 91 that also serves as the deceleration table 90. Similarly, the side joggers 15 are opened and closed for each certain number of sheets, and the end surfaces on both sides of the sheet are opened. Align, align correctly and stack sequentially. Then, the stacked lifted sheets 17 are automatically lowered by the sheet upper surface detector so that the upper surfaces of the sheets are always at a fixed position. Lifting lift 17
Finally stops at the descent.

The control operation of this embodiment is the same as the control operation described with reference to FIG. 6, and will not be described again.

[0046]

As described above, according to the sheet stacking apparatus of the present invention, the traveling speed is clamped at the fixed position of the rear end portion of the traveling sheet after cutting regardless of the sheet cutting length cut by the sheet cutter. Since the sheets can be stacked directly without decelerating the sheets without overlapping the sheets, it is possible to prevent the occurrence of scratches and the like due to the friction of the sheet surfaces due to the overlap, and to convey the sheet conveyer section after the cutting machine. The length of can be shortened.

Further, since the auxiliary fork and the frequency fork are provided, only one rayboy device is required and the structure is simplified.

Further, even if sheets of various materials are used, there is an effect that the sheets can be normally fed to the stacking.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an exemplary embodiment of the present invention.

FIG. 2 is a side view of a deceleration roll.

FIG. 3 is a diagram for explaining an operation.

FIG. 4 is a diagram for explaining the operation.

FIG. 5 is a diagram for explaining the operation.

6 is a diagram showing a control system of the sheet stacking apparatus of FIG.

FIG. 7 is a diagram showing a positional relationship of a rotating device.

FIG. 8 is a diagram showing a speed pattern of a rotating device.

FIG. 9 is a diagram showing another embodiment of the present invention.

FIG. 10 is a perspective view of a deceleration table.

FIG. 11 is a diagram showing a conventional technique.

[Explanation of symbols]

 1 Cutting Machine 2 Sheet Conveyor 3 Sheet Holding Conveyor 4 Holding Roll 5 Holding Belt 6 Sheet Detector 7 Speed Change Mechanism 8 Rotation Mechanism 9 Free Roller 10 Decelerating Table 11 Auxiliary Fork 12 Main Fork 14 Stopper 15 Side Jogger 16 Stacking 17 Lifting Lift 18 Sheet guide belt 20 Sheet conveyor 25 Cut sheet 27 Non-slip roll 30 Clamp device 40 Rayboy device 50, 68 Pulse generator 52 F / V converter 54 Speed command selection circuit 56 Servo motor 57 Servo amplifier 58 Phase setter 60 Origin Sensor 64 Deviation counter 66 Gate 70 Top dead center position deviation counter 72,78 D / A converter 74 Speed command clamp circuit 76,80 Adder / subtractor 90 Deceleration table

Claims (3)

[Claims] 1. A sheet stacking device for stacking sheets that have been cut by a cutting machine and are traveling in a stacking, and a conveyor that conveys the sheets cut by the cutting machine while maintaining a predetermined sheet interval, and during conveyance of the sheets. The clamp device that clamps the reference position of the rear end of the sheet to reduce the traveling speed of the sheet to the optimum speed necessary for stacking the sheets in the stacking order, a lifter that raises and lowers the stacking, and a stacking device that stacks the sheets in the stacking. When a predetermined number of sheets are reached, an auxiliary fork that is inserted into the stacking, a main fork that is inserted into the stacking at the same time when the lifter descends after the insertion of the auxiliary fork, and a servo motor that drives the clamp device, A servo amplifier for controlling this servo motor, and A position detector that detects the trailing end position of the sheet being conveyed by the conveyor, a first encoder that detects the speed of the conveyor, a second encoder that detects the rotation speed of the servo motor, and a clamp device of the clamp device. An origin detector that detects an origin, a phase setting device that sets the reference position, an output of the first encoder, an output of the second encoder, an output of the origin detector, and the position detector A first control circuit for performing phase speed tuning control of the clamp device based on the output of the phase setting device and the output of the phase setting device, the output of the second encoder, and the output of the origin detector. And a second control circuit for performing the top dead center positioning control of the clamp device based on the sheet stacking device. 2. The clamp device includes a rotating device having a free roller at a tip portion thereof and a deceleration roll, and the free roller comes into contact with the deceleration roll every time the rotating device makes one revolution. 2. The sheet stacking device according to claim 1, wherein the sheet stacking device is clamped. 3. The clamp device includes a rotating device having a free roller at a tip portion thereof, and a speed reduction table which is reciprocally driven in parallel with the rotating device, and the rotating device is 1
2. The sheet stacking device according to claim 1, wherein the free roller contacts a reference position of the deceleration table and clamps the sheet each time the free roller rotates.