JPH09226022A - Method for controlling sheet stock amount of squaring part of corrugated fiberboard case manufacturing machine and apparatus therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the changes (abrupt accelerating or decelerating) of a sheet feeding speed in the case of maintaining the stock amount of corrugated fiberboard sheets stored in a stacker of a squaring part from a folder gluer in a suitable range in a corrugated fiberboard case manufacturing machine. SOLUTION: The sheet length (a) of a corrugated fiberboard sheet CS fed to the stacker 2 of a squaring part 1 from the detection of a feed sheet sensor 7 is measured, and the feed sheet length (b) of the end of the sheet CS fed from the lowermost stage of the stacker 2 after the detection of a feed sheet sensor 8 is measured. The total sum of the stayed (storage) sheet length in the stacker 2 is obtained based on the difference between the lengths (a) and (b), and the feeding speed V2 is regulated so that the sum of the sheet length becomes equal to the sum of a predetermined suitable sheet length. Thus, the control considering the half end of the sheet can be conducted, and the change width of the speed V2 can be reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for controlling the amount of sheets accumulated in a square box of a corrugated board box making machine.

[0002]

2. Description of the Related Art Conventionally, for example, as shown in FIG.
In the corrugated board manufacturing process, the corrugated board is supplied to, for example, a flexo printer FP, and the printed corrugated board is pasted and folded with a folder gluer FG.
There is known a method in which a deviation in gluing or the like is corrected in Q, and further, a predetermined number of stacks are formed by a counter ejector CE, for example. In the squaring unit SQ, sheets are normally loaded from above, a predetermined number of sheets are accumulated inside, and the sheets are discharged one by one from the lower side to the counter ejector CE side. Also called a straightening top stacker.

[0003]

Here, it is important to keep the accumulated amount of sheets existing in the squared portion SQ within a substantially constant range in order for the corrugated board box making line to operate smoothly. If the sheet accumulation amount of the squared portion SQ is too large, the line will be hindered, but even if it is too small, the weight of the sheet accumulation amount that assists the adhesion of the glue is insufficient, which is not preferable.

Therefore, in the past, the number of sheets sent to the squaring section SQ and the squareing section SQ
The number of sheets sent from Q is detected, and the accumulated amount is controlled so that the accumulated number of sheets in the squaring unit SQ becomes substantially constant. Generally, the upstream side, that is, the speed of the printing line or the folder gluer is preferentially set, so that the feeding speed of the sheet from the squaring unit SQ is adjusted to adjust the number of sheets stored in the squaring unit SQ. .

Such a conventional method has relatively few problems when the box making line is at a low speed, but when operating at a high speed, the sheet feeding speed is rapidly accelerated or decelerated if the number of stored sheets deviates. However, there is a problem that the control of the number of accumulated sheets becomes unstable.

An object of the present invention is to more accurately grasp the accumulated amount of sheets in the squaring portion and to stabilize the control of the accumulated amount based on this.

[0007]

According to the present invention, the accumulated amount of sheets in the squared portion is detected not by the number of sheets for each sheet but by an odd amount based on the sheet length, and the sheet is detected. Normally, the speed control of the discharged sheet is carried out so that the long-term accumulated amount becomes almost constant. This suppresses sudden acceleration and deceleration that accompany sheet feeding, and reduces fluctuations in sheet ejection speed. This also contributes to the stable operation of the counter ejector when it is provided downstream.

That is, in the method according to the present invention, corrugated board sheets (hereinafter simply referred to as sheets) are sequentially fed into the square ring section of a corrugated board box making machine and accumulated in a laminated state.
In the process of being sequentially sent out while being straightened, the accumulated amount of sheets existing in the squared portion is converted into a sheet length of those sheets which is a reference smaller than the counting reference for each sheet, and the sheet length reference The sheet storage amount of the squared portion is controlled so that the storage amount falls within a predetermined range.

Further, according to the present invention, in the sheet accumulating amount control device in the square ring section in which the sheets fed by the sheet feeding means are accumulated / rectified in a stacked state and the sheets are sequentially fed by the sheet feeding means, Infeed sheet sensor,
It includes a fed-in sheet length detection means, a fed-out sheet sensor, a fed-out sheet length detection means, and a sheet accumulation amount control means. The fed-in sheet sensor detects the sheet fed into the squaring section, and the fed-in sheet length detecting means detects the sheet fed into the squared portion based on the moving distance of the sheet after the leading-edge sheet sensor detects the leading edge of the sheet. Detect the length.

On the other hand, the sending-out sheet sensor detects the sheet sent out from the squaring section, and the sending-out sheet length detecting means detects the sheet based on the moving distance of the sheet after the sending-out sheet sensor detects the leading edge of the sheet. The length of the fed sheet is detected. Further, the sheet accumulation amount control means controls the sheet feeding amount of the sheet feeding means so that the sheet accumulation amount in the squared portion defined based on the feeding sheet length and the feeding sheet length is maintained within a predetermined range. And at least one of the feeding amounts of the sheet feeding means is controlled.

As described above with reference to FIG. 12, when priority is given to the upstream printing line speed and the like, the sheet accumulation amount is adjusted by controlling the sheet feeding amount of the sheet feeding means. However, when the process speed on the downstream side is prioritized, the sheet accumulation amount can be adjusted by increasing or decreasing the feeding amount of the sheet feeding means. Alternatively, it is possible to control the sheet accumulation amount as a whole by increasing or decreasing both the sheet feeding amount and the sheet feeding amount. Further, in the case of controlling the feed amount (or feed amount) of the sheet, it is usually possible to increase or decrease the sheet speed, but for example, to narrow or lengthen the interval of the feeding pitch (ejection pitch). It is also possible to control the accumulated amount. The feeding amount (feeding amount) is a concept including such a sheet speed and a discharging pitch.

In addition to the above-mentioned device, a sheet accumulated amount calculating means for converting at least a part of the accumulated amount of sheets existing in the squaring portion into a sheet length is provided, and the sheet accumulated amount calculated by this means. It is also possible to provide, for example, a sheet feed-out control means for controlling the feed-out speed of the sheet feed-out means so that the value is maintained within a preset range. Here, all of the accumulated amount of sheets existing in the squaring portion is converted to the sheet length for calculation, that is, the accumulated amount of sheets is calculated by converting to the sum of the sheet lengths of all the sheets existing in the squaring portion. For example, the feeding speed of the feeding means can be controlled so that the total sheet length is maintained within a predetermined range. However, in addition to this, for example, regarding the sheet length on the way to be fed in and the sheet length on the way to be fed out, the accumulated amount in the squared portion is calculated on the basis of the sheet length, and other than that, it is already stored in the squared portion and is in a laminated state Some items can be grasped on the basis of the number of sheets for each sheet.

In this case, the accumulated amount can be detected as, for example, XX sheets + ΔΔ sheet length (an odd value smaller than one sheet). Even when the accumulated amount is calculated by the sum of the sheet lengths of all the sheets, when comparing this with the set value as the actual value, the sheet length may be replaced with the number of sheets including the fraction. For example, the accumulated amount of 10.45 sheets.

As described above, the accumulated amount of sheets in the squaring portion is grasped not by the number of sheets per sheet, but by the sheet length standard in consideration of the fraction of the number of sheets, or in consideration of the sheet length standard. As a result, the accumulated amount can be grasped with higher accuracy than the conventional number-based standard. Therefore, by setting the set accumulation amount based on the sheet length and setting the feeding sheet speed to match this, the change in the sheet accumulation (retention) amount is reduced,
This enables speed control without unevenness in the sheet feeding speed as shown in FIG. 8, for example. That is, the fluctuation range of the sheet feeding speed becomes smaller than that in the conventional method, and the feeding speed can be stabilized.

By the way, as shown in FIG. 9, the peripheral length of the printing cylinder for performing printing (for example, flexographic printing) upstream of the squared portion is Ls, and the sheet length of the corrugated cardboard sheet to be printed (in the feeding direction). ) Is L1, one revolution of the printing cylinder is one shorter than the cylinder circumference Ls.
When printing on a single sheet (sheet length L1), it is common to use a method in which there is a gap between the sheets sent to the square ring section and almost no gap between the sheets sent out from the square ring section. is there. here,
If the actually detected sheet length is used as the sheet length data as it is, as shown in FIG. 10A, the accumulation amount based on the sheet length of the square portion fluctuates in the gap between the sheets. The sheet feeding speed can be controlled so as to follow it, but as another method, by multiplying the sheet length being fed by the above L1 / Ls, as shown in FIG.
As shown in (b), it is possible to average the changes in the accumulated sheet length based on the sheet length. As a result, it is not necessary to change the sheet feeding speed frequently, and stable control is possible.

Further, such an averaging method using L1 / Ls can be directly reflected on the sheet feeding speed instead of the sheet accumulation amount. That is, a substantially proper value of the sheet feeding speed V2 with respect to the sheet feeding speed V1 is set based on (L1 / Ls) V1. Where V2
= (L1 / Ls) V1 or an appropriate correction value may be added. Although the delivery speed V2 is determined in this way, the sheet storage amount of the squared portion is ultimately controlled, but from a different point of view, the sheet storage amount itself is not used as a parameter, that is, the sheet storage amount is fed back. Instead of performing the closed-loop control of the sheet feeding speed, the open-loop control that uniquely sets the feeding speed can be performed by the averaging process based on the above L1 / Ls. In that case, it is possible to increase the reliability of control by separately adding a height sensor or the like for checking the maximum / minimum amount of sheet accumulation height.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the embodiments shown in the drawings. In FIG. 1, the squaring unit 1 is mainly composed of a so-called top stacker 2, and a corrugated cardboard sheet CS (hereinafter, simply referred to as a sheet) fed from a feeding conveyor 3 is loaded into the stacker 2 from above and in a stacked state. Accumulated. This sheet CS is sent from the upstream folder gluer side, and is in a folded and glued state.
As is well known, by stacking on the stacker 2 and repeatedly applying an appropriate impact load from the side, the distortion of gluing is corrected before the glue hardens, and by the self-weight of the corrugated cardboard sheet in the accumulated state. Adhesion with glue is assisted.

Then, the sheets CS with the glue solidified are discharged one by one from the lower side of the stacker 2 to the counter ejector side (not shown) by the conveyer 5, where a predetermined number of sheets are stacked and bound further downstream. become. The drive shaft 6 of the feeding conveyor 3 is driven by a sheet feeding motor M1, and a pulse generator PG1 for detecting the length of the fed sheet is connected to the driving shaft 6. Further, a feed sheet sensor 7 for detecting the sheet CS fed into the entrance portion of the stacker 2
Is provided.

In contact with the bottom of the stacker 2,
The delivery conveyor 5 described above is provided, and is driven by the delivery motor M2 via the drive shaft 9.
The drive shaft 9 of the delivery conveyor 5 is also provided with a pulse generator PG2 for detecting the delivery sheet length, and at the exit of the stacker 2, a delivery sheet sensor 8 for detecting the delivery sheet CS. Is provided.

Then, the number of sheets CS of sheets n corresponding to the difference between the number n1 of fed (supplied) sheets CS fed from above into the stacker 2 and the number n2 of fed sheets CS fed out from the lowermost portion is the stacker 2 It is accumulated in the inside, and sequentially moves downward every time one sheet is discharged, and is discharged from here by coming into contact with the delivery conveyor 5.

In order to keep the number of sheets CS accumulated in the stacker 2 substantially constant, conventionally, the feeding speed V1 and the feeding speed V2 of the sheets CS are made substantially equal to each other, and the sheets in the stacker 2 are made substantially the same. Number of sheets n = n
1-n2 was calculated, and fine adjustment speed control of the sending speed V2 was performed so that this value would be constant. In this embodiment,
The point that V2 is almost equal to V1 is the same as the conventional one, but the speed of the feed motor M2 is controlled based on the sheet length, which is smaller than the number of sheets (measurement (counting) unit), as a reference. is there.

The delivery motor M2 is controlled by a sheet delivery speed control device 12 via a motor drive control section (motor driver) 11. The pulse generators PG1 and PG2, the feed sensor 7 and the feed sensor 8, and the motor drive control unit 11 are connected to the sheet feed speed control device 12.

First, the concept of control will be described with reference to FIG. 2. The moving amount of the sheet CS (moving distance of the feeding conveyor 3 after the leading edge of the sheet CS fed from the upstream is detected by the feeding sheet sensor 7). ) Is measured to obtain the fed-in sheet length a. It can be said that this measures the odd sheet portion of one sheet. On the other hand, the sending-out sheet sensor 8 detects the leading end of the sheet CS discharged from the lowermost part of the stacker 2, and the sending-out sheet length b based on the moving distance of the sending-out conveyor 5 thereafter.
Is measured.

Then, as shown in the following equation, based on the sum of the number of sheets accumulated in the stacker 2 multiplied by the sheet length per sheet and the difference between the fed sheet length and the fed sheet length. Then, the sheet accumulation amount in the stacker 2 can be obtained by converting it into the sheet length.

[0025]

[Equation 1]

The delivery speed V is set so that the actual sheet length becomes substantially equal to the preset optimum accumulated sheet length.
By controlling 2, the accumulated amount can be calculated more accurately up to the so-called fractional number of sheets compared to the control for each sheet, so the sheet retention length measurement accuracy is, for example, one digit higher than before. Become. Therefore, the delivery speed V2 is prevented from rapidly increasing or decreasing (see FIG. 8), and the delivery speed V2 can be stably changed.

The sheet feeding speed control device 12 of FIG.
Is, for example, as shown in FIG.
4, the computer 12 including the RAM 15 and the bus 16 can be mainly configured, and its interface 1
8 through the sensors 7, 8 and the pulse generator P
G1, PG2, the motor driver 11, etc. are connected.

The ROM 14 stores a sheet feeding speed control program of the present case and other necessary programs, and the RAM 15 stores optimum accumulation sheet length (stack sheet length) setting data, which is calculated as described above. The accumulated sheet length is stored and the feeding speed V
1, sending speed V2, sending speed correction amount (change amount) R
Etc. will be temporarily stored.

As shown in FIG. 5, in addition to the above device configuration for controlling the accumulated amount of sheets, the upper limit sensor S1, the middle stage sensor S2, and the lower limit sensor of the stacker 2 are supplementarily provided. S3 can also be provided. Here, if the state in which the sensors S2 and S3 detect the sheet CS and both are turned on is appropriate, the sensor S1 is turned on, which means that the sheet CS is extremely large. Therefore, for example, when the discharge is continued for a fixed time at, for example, 150% of the normal sending speed (discharge speed) V2 and the lower limit sensor S3 is turned off, the sheet CS in the stacker 2 is very small. This means that it is possible to perform control such as stopping the discharge of the sheet CS. However, since these controls are the same as the conventional ones, they may be used for safety when the sheet accumulation amount control of the present case is erroneously operated, or for the initial stage of sheet loading.

Next, an example of the control of this embodiment will be described with reference to the flowchart shown in FIG. Step S1 (hereinafter,
The infeed sheet CS is detected by the infeed sheet sensor 7 according to (S1). Further, in S2, the fed sheet length a is measured. This may be obtained based on the number of pulses of the pulse generator PG1 after the feeding sheet sensor 7 detects the leading edge of the sheet CS until the trailing edge is detected. On the other hand, of the accumulated sheets CS,
The lowermost one is sent out by the sending-out conveyor 5, and the sent-out sheet sensor 8 detects the sent-out sheet CS (S3). Further, in S4, the fed sheet length b is measured. Also in this case, the pulse generator PG after the sending sheet sensor 8 detects the leading edge of the fed sheet CS and thereafter detects the trailing edge of the sheet CS.
It is calculated based on the number of pulses of 2.

Further, in S5, the actual accumulated (stock) sheet length La is calculated. This is based on the formula
The total number of sheets CS accumulated (multiplying) may be calculated by multiplying the sheet length L1 per sheet by the number of sheets CS and the difference between the fed sheet length a and the fed sheet length b.

Further, in S6, the actual accumulated sheet length La
Then, it is determined whether or not the predetermined appropriate cumulative sheet length Lb is substantially equal. This proper accumulation sheet length L
b is usually determined with a certain width, and if the determination in S6 is YES, the delivery speed (discharge speed) in S7
V2 is maintained and returns. On the other hand, when the actual accumulation sheet length La is larger than the proper value Lb (excessive), the delivery speed V2 is adjusted to increase in S9 through S8. On the other hand, when the actual sheet length La is smaller than the proper value Lb (too small), the delivery speed V2 is adjusted so as to be reduced in S11 and the process returns.

Incidentally, as shown in FIG. 7, it is premised that the printing cylinder of a flexographic printing machine or the like is upstream, but when the entire circumference of this printing cylinder is Ls, the actual sheet length is generally smaller than this. Set to short L1. It is usual that a certain distance (Ls-L1) exists between the sheet groups that are sent downstream in this state. Now Figure 6
As shown in, the sheet length does not exist in the blank portion (gap) of the print cylinder circumferential length Ls except the actual fed sheet length L1. On the other hand, there is almost no gap between the sheets sequentially sent out from the lowermost stage of the stacker 2 in FIG.

Therefore, when the actual feeding sheet length is adopted, the blank portion without the sheet length is
Since the fed-in sheet length becomes zero, this portion has a function of periodically reducing the accumulated amount of sheets, and as a result, the feeding speed V2 is decelerated in the portion without this sheet length and increased in the portion L1 ( Or, it changes to the return side, which becomes a factor for varying the sending speed V2.

In order to suppress such a variation in V2, it is also possible to exclude an area having no sheet length, assume an averaged fed sheet length, and calculate the accumulated sheet length La 'based on this. That is, as shown in the following equation,
In order to average the seat length L1 with the cylinder circumferential length Ls,
Assuming a value obtained by multiplying the actual feed sheet length a by L1 / Ls as an average feed sheet length, such an average sheet length is continuously supplied while the feed conveyor is operating. I think.

[0036]

[Equation 2]

The equation defines the sheet feeding speed V2 based on this. Conceptually, if the optimum accumulated sheet length and the averaged (actual) accumulated sheet length are equal, the feeding speed V2 is adjusted to the feeding speed V1 and the sheet length corrected speed (L1 / Ls) V1. However, if the actual accumulation sheet length is smaller than the optimum accumulation sheet length, adjustment to reduce V2 may be made, and if the actual accumulation sheet length is larger than the optimum accumulation sheet length, adjustment to increase V2 may be made. Recognize.

FIG. 11 shows an example of control on the premise of averaging the lengths of the fed sheets. The feeding sheet detection in step R1 and the feeding sheet length measurement in R2 are the same as S1 and S2 in FIG. 4, but the feeding sheet speed V1 is measured by the number of PG1 pulses per unit time in R3. The detection of the sending sheet of R4 and the measurement of the sending sheet length of R5 are the same as S3 and S4 of FIG.
In step 6, the sending sheet speed V2 is measured by the number of PG2 pulses per unit time.

Further, at R7, the actual accumulated (stock) sheet length La is calculated. This is based on the above equation, by multiplying the number of accumulated sheets (n1-n2) by the sheet length L1 per sheet, and taking the difference between the fed sheet length a and the fed sheet length b. , The sum of these should be calculated. Next, after calculating an almost appropriate sheet feeding speed (L1 / Ls) V1, the sheet feeding speed V2 is set to (L1 / Ls) V1-k1 (La-Lb).
As a result, when La becomes larger than Lb, V2 is decelerated, and conversely, when La becomes smaller than Lb, V2 is accelerated and La is maintained at approximately Lb.

The above description is merely illustrative, and the present invention is not limited to these examples, and it goes without saying that various modifications can be made based on the knowledge of those skilled in the art. For example, without using both PG1 and PG2,
Only the sheet is detected by the sensors 7 and 8, and PG1 and P
For the minute feed sheet to be measured by the output of G2, a method of substituting an approximate value calculated from the feed speed per sheet feeding or feeding of the immediately preceding sheet obtained from the outputs of the sensors 7 and 8 or PG2 Without using P
Using the G1 and the sensors 7 and 8, each time the sensor 8 detects the leading edge or the trailing edge of the sheet, a so-called sampling control method is used to accurately detect the sheet accumulation amount by the output of the sensor 7 and PG1. You can also

[Brief description of drawings]

FIG. 1 is a diagram conceptually showing an example of a device configuration of the present invention.

FIG. 2 is an explanatory diagram of the operation.

FIG. 3 is a block diagram showing an example of a device configuration.

FIG. 4 is a flowchart showing an example of a control flow.

FIG. 5 is a conceptual diagram when an auxiliary sensor is used.

FIG. 6 is a diagram showing a relationship between an actual feed sheet length and an averaged feed sheet length.

FIG. 7 is a diagram showing a relationship between a print cylinder peripheral length and a sheet length.

FIG. 8 is a graph showing actions and effects.

FIG. 9 is an explanatory diagram showing an example of the concept of sheet feeding and sheet feeding in relation to a printing cylinder.

FIG. 10 is an explanatory view showing a case where the actual lengths of fed sheets are averaged and a case where they are not averaged in comparison.

FIG. 11 is a flowchart of an embodiment different from that of FIG.

FIG. 12 is a conceptual diagram showing an example of a corrugated board box making machine to which the present invention can be applied.

[Explanation of symbols]

 1 Squarer 2 Stacker 3 Feeding conveyor 5 Feeding conveyor 7 Feeding sheet sensor 8 Feeding sheet sensor M1 Feeding motor M2 Feeding motor PG1, PG2 Pulse generator

Claims (9)

[Claims] 1. A sheet existing in a square corrugated sheet (hereinafter simply referred to as a sheet) existing in the square box during the process of being sequentially fed into a square section of a corrugated box making machine, accumulated and corrected in a laminated state, and then sequentially sent out. Is calculated by converting the accumulated amount of the sheets into a sheet length of those sheets, which is a standard smaller than the counting standard for each sheet, and the sheet accumulation of the squared portion is performed so that the accumulated amount of the sheet length standard falls within a predetermined range. A method for controlling the accumulated amount of sheets in a squared part of a corrugated board box making machine, characterized by controlling the amount. 2. The feeding speed of the sheet is V1, the feeding speed of the sheet is V2, the circumference of a printing cylinder for printing on the sheet on the upstream side of the squaring portion is Ls, and the total length of the sheet is L1 (however, Ls ≧ L
1) In the case where the feeding of the sheet is carried out at a pace of one sheet per one circumference of the printing cylinder and the feeding of the sheet is carried out by a method in which there is almost no gap between the sheets, the feeding speed V2 of the sheet Is set on the basis of (L1 / Ls) V1. 3. A peripheral length of a printing cylinder for printing on the sheet upstream of the squaring portion is Ls, and a total length of the sheet is L1 (where Ls ≧ L1). In the case where the printing is performed at a pace of one sheet per one circumference of the printing cylinder, and the feeding of the sheet is performed by a method in which there is almost no gap between the sheets,
The change in accumulated sheet length is averaged based on the fact that the sheet length of the sheet being fed is multiplied by L1 / Ls when the fed sheet length is obtained. The sheet accumulation amount control method described. 4. A sheet accumulating amount control device in a squaring unit for accumulating / correcting corrugated cardboard sheets (hereinafter simply referred to as sheets) sequentially fed by a sheet feeding means in a laminated state, and for sequentially feeding the sheets by a sheet feeding means. A feeding sheet sensor for detecting the sheet fed to the squaring unit, and a feeding sheet length of the sheet based on a moving distance of the sheet after the leading sheet sensor detects the leading edge of the sheet. Infeed sheet length detection means, a delivery sheet sensor for detecting the sheet delivered from the squaring section, and a delivery sheet sensor for detecting the sheet based on the moving distance of the sheet after the delivery sheet sensor detects the leading edge of the sheet. Detects the length of sent sheet A sheet feeding amount of the sheet feeding means so that the sheet accumulation amount in the square ring portion defined based on the feeding sheet length and the feeding sheet length is maintained within a predetermined range. And a sheet accumulation amount control means for controlling at least one of the feeding amounts of the sheet feeding means, and a sheet accumulation amount control device in a square section of a corrugated board box making machine. 5. The sheet storage amount control means increases the delivery speed of the sheet delivery means when the sheet storage amount is larger than a proper value, and decreases the delivery speed when the sheet storage amount is smaller than the proper value. The sheet accumulation amount control device according to claim 4. 6. A sheet accumulating amount control device in a square ring section for accumulating / correcting corrugated cardboard sheets (hereinafter, simply referred to as sheets) sequentially fed by a sheet feeding means in a stacked state, and for sequentially feeding the sheets by a sheet feeding means. A feeding sheet sensor for detecting the sheet fed to the squaring unit, and a feeding sheet length of the sheet based on a moving distance of the sheet after the leading sheet sensor detects the leading edge of the sheet. Infeed sheet length detection means, a delivery sheet sensor for detecting the sheet delivered from the squaring section, and a delivery sheet sensor for detecting the sheet based on the moving distance of the sheet after the delivery sheet sensor detects the leading edge of the sheet. Detects the length of sent sheet An extension sheet length detection means, a sheet accumulation amount calculation means for calculating at least a part of the accumulation amount of the sheet existing in the squaring portion into the sheet length, and the sheet accumulation amount maintained within a predetermined range. And a sheet feed-out control means for controlling the feed-out speed of the sheet feed-out means as described above. 7. The sheet accumulation amount calculation means calculates the accumulation amount of the sheets existing in the square ring portion by converting it into a total sum of the sheet lengths of the sheets. 7. The control device according to claim 6, wherein the feeding speed of the sheet feeding means is controlled so that the total sum of the sheet lengths existing in the ring portion is maintained within a predetermined range. 8. A feeding speed of the sheet by the feeding means is V1, a feeding speed of the sheet by the feeding means is V2, and a circumference of a printing cylinder for printing on the sheet on the upstream side of the feeding means is set. Ls,
The total length of the sheet is L1 (where Ls ≧ L1), the feeding of the sheet is performed at a pace of one sheet per one circumference of the printing cylinder, and there is almost no gap between the sheets for feeding the sheet. 8. The sheet accumulation amount control device according to claim 4, wherein the sheet feeding speed V2 is set based on (L1 / Ls) V1. 9. The feeding length of the sheet is set to Ls, where Ls is the circumference of a printing cylinder for printing on the sheet on the upstream side of the feeding means, and L1 is the total length of the sheet (where Ls ≧ L1). In the case where the sheet is sent out at a pace of one sheet per cylinder, and the sheet is sent out by the sending means in a system where there is almost no gap between the sheets, when the length of the sent-in sheet is detected,
8. The sheet accumulation amount according to claim 4, wherein changes in the accumulated sheet length are averaged based on multiplying the sheet length of the sheet being fed by L1 / Ls. Control device.