JPH11115163A - Method and equipment for controlling register - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce sharply defective printing due to misregister by shifting a compensator roll to the position before interruption, at the time of restart after the interruption of printing. SOLUTION: In register control equipment wherein a compensator roll 22 provided between first and second adjacent printing units 10 and 12 is shifted to regulate automatically the length of a web W between the two printing units 10 and 12, on the basis of the amount of misregister detected as to patterns printed by the units 10 and 12 respectively, a recording button 34 for reading the position of the compensator roll 22 at the time when registers are in accord before speed reduction, on the occasion when a printing speed is reduced in regular printing, a position recording part 36 which records the read position of the compensator roll 22 and a setting button 38 for setting and inputting the recorded position of the compensator roll 22 after a target speed is reached at the time of speed increase thereafter, are provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a register control method and apparatus, and more particularly to a register control method and apparatus suitable for multicolor printing on a web made of paper or plastic film.

[0002]

2. Description of the Related Art In the case of so-called multicolor printing of two or more colors on a web made of paper, plastic film, or the like that is continuously conveyed, a picture of each color is printed at a correct position, and a shift between pictures in each color, That is, it goes without saying that the absence of misregistration is important for the quality of printed matter.

[0003] Generally, as shown in FIG. 4, two color patterns P and P 'are conceptually shown in FIG.
There is a vertical misregistration A deviating in the flow direction of the web W (vertical direction in the figure) and a lateral misregistration B deviating in a direction perpendicular to the flow direction.

[0004] The registration of multicolor printing refers to matching the printing position of a basic color (basic color) with the printing position of another color (control color). The expression that the basic color is the first color and the color to be controlled is the second color is mainly used.

[0005] Here, only the vertical register is taken up. However, when the vertical register misregistration as described above occurs in the first color and the second color patterns, as a method of correcting the misregistration, a compensator roll is used to correct the difference between the two colors. That is, a method of correcting the length (path length) of the web W between the plate cylinders for printing a pattern of each color is generally used.

Now, a method of correcting the vertical register will be described in detail below using a general gravure printing machine shown in FIG. FIG. 5 shows a first printing unit 10 for printing the first color,
2 shows a second printing unit 12 for the second color located downstream thereof.

The web W passes between the plate cylinder 14 and the impression cylinder 16 constituting the first printing unit 10, and after the first color is printed, the web W is printed on the plate cylinder 18 and the impression cylinder 20 of the second printing unit 12.
, The second color is printed, and then conveyed in the direction of the arrow to move to the next step.

If there is a vertical misregistration between the printing of the first color and the printing of the second color by the first and second printing units 10, 12, the printing unit is disposed between the two units. The vertical registration error is corrected by moving the compensator roll 22 in the direction of the arrow and adjusting the path length between the two.

The register correction for correcting the vertical register shift is generally performed automatically. Specifically, a registration mark called a register mark is printed simultaneously with the pattern on the web at a position that does not interfere with the printed pattern, and the target printing unit side including the entrance side and the exit side of the target printing unit prints the mark. It is widely practiced to perform feedback control so that a misregistration becomes zero while detecting a mark online.

In the case of FIG. 5, the register mark printed in the second color to be controlled and the register mark printed in the first color to be controlled are, for example, The detection is performed on the output side, that is, downstream of the plate cylinder 18, and the control unit (not shown) calculates the vertical misregistration from the distance between the two marks, and determines the path length between the printing units so that it becomes zero. Automatic control for changing and correcting by the roll 22 is performed.

[0011] When a printed material is produced by performing regular printing by the automatic control of the misregistration as described above, printing may be temporarily interrupted and then restarted. FIG. 6 is a time chart conceptually showing the change over time in the printing speed, the web tension between units, and the amount of register shift in this case. The following describes the case where printing is interrupted by conventional register control using this. It will be described in detail.

As shown in FIG. 6, V1 (for example,
If printing is stopped at a production speed (steady speed) of 150 m / min, deceleration is started at T1 and the impression cylinder is raised at T2 when the minimum speed of V2 (for example, 10 m / min) is reached. Then, the web W is separated from the plate cylinder, and then the line is stopped at T3. At that time, since the web tension between the printing units greatly changes during the deceleration from the time T1 to the time T2, the color registration, that is, the misregistration also largely fluctuates due to the change in the tension. In order to control the register fluctuations, the control device compensator roll 22
However, if the deceleration is too large, the control cannot be completed, and finally the misregistration exceeds the automatic controllable range (for example, ± 8 mm) shown in C in the figure, and the feedback control becomes ineffective. , Compensator roll 2
2 stops, but the misregistration increases, and T3
At this point, the printing press stops with a large deviation.

Thereafter, when resuming at the time T4, since the register is largely shifted, as in the case of a normal start operation, first, the printing printing is started at a constant low speed of, for example, 10 m / min. Then, the operator manually moved the compensator roll over time A so that the misregistration was within the automatic controllable range C, then switched to the automatic control, and confirmed that the printed printing was stable. T
Accelerate again at 5 points.

During this acceleration, the web tension between the units fluctuates, and the color registration also fluctuates accordingly. However, the printing speed gradually approaches the target production speed V1, and reaches the production speed at time T6. Thereafter, it took B hours for the automatic control to stabilize, and the register was completely registered at T7 (register shift amount =
The steady state (0) is reached. It should be noted that B
The time (convergence time) is not limited to the above-described interruption of stopping the printing press, but only the deceleration during printing at a steady speed, the deceleration that starts up without stopping and returns to the steady speed again. The same applies to the case of.

[0015]

However, as described above, if the printing machine is stopped during regular printing (production) and printing is interrupted, the register is greatly shifted. Since the operation must be performed in the same procedure as when starting printing, and when returning to a steady speed without stopping the printing press after deceleration, Since the convergence time is required, there is a problem that the productivity is reduced in any case.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and is intended to prevent misregistration occurring when printing is resumed after interruption or when the printing speed is increased to a steady speed after the printing speed is reduced. It is an object of the present invention to provide a register control method and apparatus capable of preventing a decrease in productivity due to the above.

[0017]

SUMMARY OF THE INVENTION According to the present invention, when sequentially printing two or more printing units on a continuously conveyed web, a misregistration detected for a pattern printed by each of two adjacent printing units. Based on quantity
In a register control method for automatically moving the compensator roll disposed between the two printing units and automatically adjusting the web length between the two printing units, when the printing speed is reduced at the time of steady printing, before the speed reduction, The above problem was solved by recording the position of the compensator roll at the time of registration, and moving the compensator roll to the recorded position after reaching the target speed during the subsequent acceleration. is there.

That is, in the present invention, during the production of a printed material at a steady speed, the position of the compensator roll at that time is recorded, the speed is temporarily reduced for some reason, and then the speed is increased and printing is resumed. Even if it is deviated, for example, after reaching the same target speed as the printing speed at the start of deceleration, the compensator roll is immediately moved to the previously recorded position, so that the position of the compensator roll for resuming printing is set before deceleration. Can be quickly returned to the position where the register has been registered, so that productivity can be improved.

According to the present invention, in the register control method, when the printing speed is reduced, when the printing machine is stopped after the deceleration and the printing is interrupted, when the printing is resumed thereafter, the same as the above is applied. According to the method, the shifted register can be quickly adjusted, so that the production can be quickly shifted to the actual production.

According to the present invention, in the register control method, the time when the register is in registration is the time of printing printing or the time of regular printing. In the case of printing printing, it is also possible to quickly adjust the print registration at the time of printing adjustment when resuming printing that has been interrupted. In gravure printing and the like, there is a property that, when the speed is different, the position of the compensator roll at which the printing register matches is also different. That is, the printing adjustment speed (for example, 10 m / min) and the speed during production (for example, 20 m / min).
(0 m / min), there is a difference of about 2 mm in web path conversion between the positions of the compensator rolls that match the print registration. If you want to quickly adjust the print registration when adjusting the printing when resuming the interrupted printing, perform the work of recording the position of the compensator roll according to the present invention at the printing adjustment speed before the interruption, and perform the printing after the interruption. At the time of adjustment, the compensator roll may be moved to the previously recorded position. However,
When the speed is increased after the end of the printing adjustment, the register slightly shifts, and a loss occurs during the fine adjustment of the register again. Therefore, when work other than registration is not necessary at the time of printing adjustment after restart, the position of the compensator roll at that time is recorded during the production before interruption (for example, 200 m / min), and when the production is resumed after interruption, Is the production speed from the beginning (for example, 200 m /
Min), and then moving the compensator roll to the previously recorded position eliminates register adjustment work during printing after interruption and loss after acceleration.

According to the present invention, in the register control method, when the position of the compensator roll to be recorded is a position immediately before the start of deceleration and the target speed at the time of acceleration is the speed at the start of deceleration, When the speed is increased to return to the same steady speed as at the start of deceleration, the compensator roll can be accurately returned to the original position before the start of deceleration.

According to another aspect of the present invention, when sequentially printing two or more printing units on a continuously conveyed web, based on the amount of misregistration detected for a pattern printed by each of two adjacent printing units. A register control device that moves a compensator roll disposed between the two printing units and automatically adjusts a web length between the two printing units. Reading means for reading the position of the compensator roll at the time of registration, recording means for recording the position of the read compensator roll, and the compensator roll recorded after reaching the target speed during the subsequent speed increase And the setting means for setting and inputting the position.

[0023]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a schematic configuration diagram showing a register control device according to a first embodiment of the present invention.

In the register control apparatus according to the present embodiment, the first and second printing units 10 and 12 are substantially the same as the general gravure printing press shown in FIG. 5, and a description thereof will be omitted.

In the register control apparatus according to the present embodiment, a control calculation unit 28 for calculating a register control based on a register shift amount input from a register sensor 26 provided on the output side of the second printing unit 12 is provided. And a drive control unit 30 that moves the compensator roll 22 to a position where there is no misregistration based on the calculation result by the calculation unit 28.

The register control device includes a recording button (reading means) 34 for reading the position of the compensator roll 22 when the register is registered at an arbitrary timing before deceleration, and a read compensator roll 22. Compensator roll 22 for storing (recording) the position of
And a setting button 38 for setting the position of the compensator roll stored in the position recording unit 36 to the drive control unit 30 at an arbitrary timing after the speed-up. Have been.

Therefore, in the register control device, when the recording button 34 is pressed while the register is in register during printing,
The position of the compensator roll 22 at that timing is read from the drive control unit 30 and recorded (stored) in the position recording unit 36. After the printing is resumed, when the setting button 38 is pressed when the target speed is reached, the previously recorded position of the compensator roll 22 is sent from the recording unit 36 to the drive control unit 30, and the control unit 30 controls the compensator roll. 22 is moved to that position. As a result, the register is accurately restored to the same state as before the interruption, that is, the state in which the register is correct.

Next, the operation of the present embodiment will be described in detail with reference to a time chart shown in FIG. This figure 2
Is a time chart based on the premise that printing is interrupted, which corresponds to the time chart of FIG. 6, and therefore, the same symbols are used for timings having the same meaning.

In the present embodiment, the position of the compensator roll 22 at the time of registration is recorded before the interruption, and the compensator roll 22 is promptly moved to the previously recorded position after the restart, and the shifted registration is performed. To return quickly.

That is, the recording button 34 is depressed at the point in time Ta before the printing is interrupted, and the position of the compensator roll 22 which has been registered and at a steady speed is recorded in advance.

The step of interrupting the printing from T1 to T3 includes:
This is the same as the case shown in FIG. 6, and the color registration is greatly shifted due to the fluctuation of the web tension between the printing units during deceleration, and the printing is stopped in that state.

Therefore, at the restart time T4 after the interruption, although the register is largely shifted, the printing speed is increased to the target production speed V1 without performing the manual registration, and the speed is increased. T after T6 when
By pressing the setting button 38 at the time point b, T7
At time ', the compensator roll 22 can be returned to its original position, that is, the position of the compensator roll at the time of registration at the production speed, and the register can be returned to a state where it has been accurately registered.

According to the present embodiment described in detail above, the time A required for manual operation at the time of printing, which was conventionally required, and the time required until the register becomes stable, as compared with the conventional method shown in FIG. Since T7 can be reduced to T7 ', that is, D time, the printing loss at the start of printing can be greatly reduced, and as a result, productivity can be improved.

Next, a second embodiment according to the present invention will be described with reference to FIG. 3 corresponding to FIG.

In the present embodiment, the register control device shown in FIG. 1 is applied as in the case of the first embodiment.

In the first embodiment, the position of the compensator roll 22 is recorded at the production speed before the interruption, and after the interruption, the speed of the compensator roll 22 is increased again to the production speed, and then the position of the compensator roll 22 is returned. In the present embodiment, the timing for recording the position of the compensator roll 22 is set at the time of printing adjustment before interruption.

In the present embodiment, when it is necessary to adjust the register at the time of the printing adjustment after the interruption, for example, when the printing sample at the time of printing is required, the Tc shown in the time chart of FIG. At the timing, that is, when the register is registered at the printing adjustment speed before the interruption, the recording button 34 is pressed to record the position of the compensator roll at that time.

When the setting button 38 is pressed at the time of printing adjustment when printing is resumed after the interruption, that is, at the timing of Td in FIG. 3, the register is registered at the timing of the previous Tc, ie, the printing adjustment speed before the interruption. The compensator roll is moved to the position of the timing, and the print register can be returned to a state where the print registration is correctly matched at the time T7 '.

However, in this case, as shown in FIG. 3, since the registered register is shifted when the speed is increased again at the timing of T5, the register is registered after the speed is increased, or the register is registered by automatic control. Although a loss occurs while waiting until T7 ″, compared to the conventional method shown in FIG.
You can save time.

Although the present invention has been specifically described above, the present invention is not limited to the above-described embodiment, and can be variously modified without departing from the gist thereof.

For example, in the above-described embodiment, the case where the present invention is applied to the interruption of printing has been described. However, the present invention may be applied to a case where the printing speed is changed for a short time during printing. Specifically, in the case where the speed is once reduced and the removal process is performed because the stain or the like adheres to the plate cylinder surface during printing, and then the speed is increased again without interruption, the present invention is applied immediately before the speed is reduced. By pressing the recording button of the compensator roll position, the position is recorded, and after the speed is again increased to the target speed, the register can be quickly restored by pressing the compensator roll position setting button.

In the case where the same lot is printed at different steady speeds during printing, the position of the compensator roll, which is registered when the printing speed is different, is often slightly different. Min, 200m
By recording the positions of the compensator rolls per minute and 300 m / min, respectively, it is possible to appropriately cope with the case where the restart printing speed is, for example, 100 m / min and is different from the printing speed before interruption, for example, 300 m / min. It is possible to do.

[0044]

As described above, according to the present invention,
It is possible to omit the manual operation for bringing the misregistration into the automatically controllable range at the time of printing, and to greatly reduce misregistration defective printing which occurs when the printing speed is increased after the printing is interrupted or decelerated and the printing at the steady speed is resumed. Therefore, productivity can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a main part of a register shift control device according to a first embodiment of the present invention.

FIG. 2 is a time chart showing a change over time of a printing speed, a web tension, a register shift amount, and a position of a compensator roll before and after printing is interrupted according to the first embodiment.

FIG. 3 is a time chart showing a change over time of a printing speed, a web tension, a register shift amount, and a position of a compensator roll before and after printing is interrupted according to a second embodiment.

FIG. 4 is an explanatory view conceptually showing misregistration of printing.

FIG. 5 is a schematic configuration diagram showing a main part of a conventional general multicolor printing apparatus.

FIG. 6 is a time chart showing changes over time of a printing speed, a web tension, and a register shift amount before and after printing is interrupted by a conventional printing apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... 1st printing unit 12 ... 2nd printing unit 14, 18 ... Plate cylinder 16, 20 ... Impression cylinder 22 ... Compensator roll 24 ... Guide roll 26 ... Register sensor 28 ... Control calculation part 30 ... Drive control part 32 ... Register control Unit 34: Recording button 36: Position recording unit 38: Setting button

Claims (5)

[Claims] When printing is sequentially performed on two or more printing units on a continuously conveyed web, the printing is performed based on a misregistration amount detected for a pattern printed by each of two adjacent printing units. In a register control method for moving a compensator roll disposed between units and automatically adjusting a web length between the two printing units, when the printing speed is reduced during steady printing, the register is registered before the reduction. Registering the position of the compensator roll at the time of moving, and moving the compensator roll to the recorded position after reaching the target speed during the subsequent speed-up. 2. The register control method according to claim 1, wherein when the printing speed is reduced, the printing press is stopped after the deceleration and printing is interrupted. 3. The register control method according to claim 1, wherein the register is registered at the time of printing or regular printing. 4. The register control according to claim 1, wherein the position of the compensator roll to be recorded is a position immediately before the start of deceleration, and the target speed at the time of acceleration is the speed at the start of deceleration. Method. 5. When sequentially printing two or more printing units on a continuously conveyed web, based on the amount of misregistration detected for a pattern printed by each of two adjacent printing units, the two printing units are used. In a register control device that moves a compensator roll disposed between units and automatically adjusts the web length between the two printing units, when the printing speed is reduced during steady printing, the register is registered before the reduction. Reading means for reading the position of the compensator roll at the time of recording, recording means for recording the position of the read compensator roll, and setting the recorded position of the compensator roll after reaching the target speed at a subsequent speed increase. A register control device comprising: a setting unit for inputting.