JPH08118610A - Paper width controlling method and multicolor printer - Google Patents

Abstract

PURPOSE: To quickly accommodate out-of-register by detecting a change in paper width between successive printing units in a multicolor printer and controlling hot air, to which a printing paper is exposed between the printing units, from a dryer in response to the detected change in paper width to keep the paper width constant. CONSTITUTION: Detection sensors 109a, 109b constantly detect misregistration in one side of a printing paper between a detection mark 105A printed by a printing unit 101A and a detection mark 105B printed by a printing unit 101B. When out-of-register is involved, a direction of and an amount of movement of a plate cylinder are calculated on the basis of such data, and a register controller 110 on the printing unit 101B at the rear stage causes a side motor 103B to repeatedly register a position of one of the detection marks 105A, 105B. An opening degree of a damper 123 of a dryer 120, which mixes hot air 121 and cold air 122 with each other to control a temperature of the hot air, is changed on the basis of a result of such calculation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to printing misregistration in a printing press, and more particularly to adjustment of misregistration caused by a change in paper width.

[0002]

2. Description of the Related Art Conventionally, a gravure printing machine, an offset printing machine, etc. are rotated by embedding a web (a belt-shaped material such as paper) in a concave portion or by adhering the ink to a lipophilic portion. Printing is performed by transferring ink from the plate cylinder to the web through a plate cylinder and an impression cylinder that presses the web against the plate cylinder while rotating. Several colors are transferred to the web for each color by different plate cylinders for printing. In these printing machines, it is known that misregistration between colors occurs when the width of the web (paper) changes between printing units that print each color due to temperature or the like. Conventionally, the operator has visually checked what was printed in the final printing unit for the misregistration due to the change in the width of the web (paper). The hot air temperature of the dryer in the previous printing unit was adjusted so that the registration in the paper width direction would match. The hot air temperature of the dryer was adjusted by adjusting the flow rate of steam flowing into the heat exchanger.

[0003]

[Problems to be Solved] However, in order to deal with this conventional misregistration, the operator must constantly monitor the misregistration. Since the misregistration check is performed after printing all colors, when the misregistration of the color printed first occurs, the detection is delayed and many defects occur. Even if the paper width changes due to changing the dryer temperature,
Since it takes time to check how the misregistration is corrected, it is difficult to adjust the dryer temperature. The dryer temperature is controlled by changing the amount of steam flowing into the heat exchanger, but the response is slow and difficult to adjust. There were problems such as. Under such circumstances, the present invention speedily copes with misregistration due to a change in web (paper) width in the case of a multicolor printing machine such as a gravure printing machine and an offset printing machine as described above. It is an object of the present invention to provide a printer capable of reducing the work load of an operator during printing.

[0004]

The paper width control method of the present invention is a method for correcting misregistration due to a paper width change between printing units in a multi-color printing machine such as a gravure printing machine and an offset printing machine, which is a continuous method. Change in paper width between printing units is detected, and in response to the detected change in paper width,
The feature is that the width of the paper is kept constant by controlling the hot air of the dryer that is applied to the paper between the printing units. Then, in the above, the detection of the change in the paper width between the printing units is performed by optically detecting the detection marks on both sides of the paper printed and provided in each printing unit, from the position of the detected detection marks. It is characterized in that it detects changes in paper width. In addition, the control of the warm air in the above is characterized by controlling the temperature and / or the air volume of the warm air. And, the temperature control of the hot air of the dryer is characterized by being performed by controlling the mixing ratio of the hot air and the cold temperature air, and the mixing ratio is controlled by controlling the damper opening. It is a feature. Further, the hot air control described above is performed by controlling gas heating. Further, the multi-color printing machine of the present invention has at least a means for detecting a paper width change between consecutive printing units, and a dryer for applying hot air to the paper between the printing units in response to the detected paper width change. And means for keeping the paper width constant by controlling.
The control of the warm air in the above is a control of the temperature and / or the air volume of the warm air. Further, the temperature control of the hot air of the dryer in the above is characterized by being performed by controlling the mixing ratio of the hot air and the cold temperature air, and the mixing ratio is controlled by controlling the damper opening. It is characterized by that. In the above, as the cold temperature, air having a substantially room temperature may be used.

[0005]

According to the paper width control method of the present invention, the paper width change between the continuous printing units is detected, and the warm air of the dryer is controlled between the printing units according to the detected paper width change. Thus, the change in the paper width between the printing units is automatically detected at all times, and the paper width is corrected correspondingly to keep the paper width constant. The width of the paper can be quickly controlled by controlling the temperature and / or the volume of warm air. Specifically, the temperature of the hot air of the dryer is controlled, the mixing ratio of the hot air and the cold temperature (approximately room temperature) is controlled by the damper opening control, and the paper width is easily and quickly controlled. It is supposed to be possible. Then, by detecting the change in the paper width between the printing units by the detection marks provided on both sides of the paper printed and provided in each printing unit,
This is the same as the conventional registration mark (registration mark) handling, and is relatively easy to detect optically.
Further, the multi-color printing press of the present invention has such a configuration that it is possible to automatically and always cope with the paper width change between the printing units and adjust the misregistration due to the paper width change. The paper width can be quickly controlled by controlling the temperature and / or the volume of warm air.

[0006]

EXAMPLES Example 1 of the multi-color printing press of the present invention will be given.
Based on this, the multicolor printing press of the present invention and the paper width control method of the present invention will be described. FIG. 1 is a schematic view of the main part of this embodiment. In FIG. 1, 100 is a multicolor printing machine, 101A,
101B is a printing unit, 102A and 102B are plate cylinders,
103A, 103B are sideless motors, 104A, 10
4B is paper (web), 105A and 105B are detection marks, 109a and 109b are detectors (sensors), 110
Is a register controller, 111 is a damper controller,
120A and 120B are dryers, 121 is hot air, 12
2 is cold air, and 123 is a damper section. For the sake of simplicity, FIG. 1 shows only the two continuous printing units 101A and 101B of the multicolor printing press 100 of the first embodiment.

The paper 104A on which the ink of a predetermined color is printed by the printing unit 101A is sent to the printing unit 101B in the subsequent stage and printed with the ink of another color. Generally, the printing unit 101A and the printing unit 101B are used. Corresponding positions of the printed pattern may be displaced (misregistration occurs), and registration marks 105A and 105B for misregistration check are provided at both ends of the paper (web) at the time of printing by each printing unit. Thus, the misregistration between the printing units is checked and corrected. Regarding the misregistration in the lateral direction (paper width direction), in general,
The plate cylinder is moved to one side of the detection marks 105A and 105B by the sideless motor 103B so as to be corrected. However, in the case of this method, when the paper width itself changes, the other side of the detection marks 105A and 105B do not match. This disagreement is the amount of change in the paper width itself. The multi-color printing press of this embodiment is intended to control the temperature of hot air from the dryers 120A and 120B between printing units to control the amount of change in the paper width itself on paper.

The operation of correcting the misregistration caused by the paper width change of the apparatus of this embodiment will be described below with reference to FIG.
FIG. 2 is an operation flow chart of paper width control in the multicolor printing press of this embodiment, FIG. 3 is a diagram for explaining correction based on the detection mark, and FIG. 3A is a printing unit 10 of FIG.
FIG. 3B shows a case where the paper width is widened from 1A to the printing unit 101B, and FIG. 3B shows a state where one mark (left side) is aligned by adjustment in FIG. 3A. In the apparatus of this embodiment, the detection sensors 109a and 109b shown in FIG. 1 constantly detect the detection mark 105A printed by the printing unit 101A and the detection mark 10 printed by the printing unit 101B.
Detect the deviation of 5B from one side (left side) of the paper (S
201), if there is misregistration, the plate cylinder movement direction and movement amount are calculated based on the data (S202), and the registration controller 110 of the printing unit 101B in the subsequent stage calculates one side of the detection marks 105A and 105B. (Fig. 3
Set the position of the detection mark on the left side of (a) to the sideless motor 1
03B (S203). Below S201-S
203 A Repeat. If there is no misregistration after S201, S201 is repeated. If there is no misregistration after S201, 105A and 10
The temperature of the dryer 120A is adjusted via the damper controller 111 as follows so as to correct the amount of change in the paper width by the amount that the position of the detection mark on the other side of 5B (on the right side in FIG. 3B) does not match. To do. First, since the registration shift of the one (left) detection mark has already been corrected,
Detects the amount of positional deviation of the other (right) detection mark, which corresponds to the amount of change in the paper width. (S204) If there is a misregistration amount, the change direction of the temperature of the dryer warm air and its amount are calculated (S205), and then the damper opening of the dryer is calculated based on this calculation result. (S
206) Next, based on this calculation result, the damper opening of the dryer is changed. (S207) For example, as shown in FIG. 3B, Δe, K _p , and ΔT are
Paper width change amount, control gain, dryer 120A
ΔT = K _p × (-Δ
e). After that, (S204 to S207) is repeated again. If there is no misregistration after S204 (positional shift of the detection mark on the right side), S204 is repeated.
From the above, even if the paper width itself changes,
The paper width change is automatically corrected.

The dryer 120 has hot air 121 and cold air 1
The hot air temperature is controlled by mixing 22 and 22 with a damper (valve) 123 in a predetermined ratio.
This makes it possible to change only the temperature while keeping the air volume of the dryer 120 constant. The damper controller 111 controls the damper (valve) 123 based on the data from the detectors 109a and 109b that detect the states of the register marks 105A and 105B, and adjusts the mixing ratio of the hot air 121 and the cold air 122. The instruction of the correction amount to the damper controller 111 may be issued via the register controller 110 as in the apparatus of the present embodiment, or may be newly calculated based on the data from the detectors (sensors) 109a and 109b. . The method of changing the temperature while keeping the air volume constant is not limited to the method of this embodiment. A method of controlling gas heating and changing air may be used.

Next, a second embodiment of the multi-color printing press of the present invention will be described, and the multi-color printing press of the present invention and the paper width control method of the present invention will be described based on this. FIG. 4 is a schematic view of the main part of this embodiment. In FIG. 4, 400 is a multi-color printing machine,
401A and 401B are printing units, 402A and 402
B is a plate cylinder, 403A and 403B are sideless motors, 40
4A and 404B are paper (web), 405A and 405B are detection marks, 409a and 409b are detectors (optical sensors), 410 is a register controller, and 420A and 420B.
Is a dryer, 421 is a temperature controller, 422 is a fan motor, 450 is an arithmetic unit, 460 is a sequencer of this machine,
For the sake of simplicity, FIG. 4 shows only the two continuous printing units 401A and 401B of the multicolor printing machine 400 of the second embodiment. Also in the case of this embodiment, the paper 404A on which the ink of the predetermined color is printed by the printing unit 401A is sent to the printing unit 401B of the subsequent stage and is the same as the multicolor printing machine of the first embodiment, and the ink of another color is printed. The printing unit 401A and the printing unit 4 are generally used for printing.
The corresponding positions of the pattern printed with 01B may be misaligned (misregistration occurs), and the registration marks 405A and 405B for misregistration check at both ends of the paper (web).
Is provided at the time of printing in each printing unit, and thereby the misregistration between the printing units is checked and corrected. Also in the case of the present embodiment, the detection marks 405A, 40A regarding the misregistration in the lateral direction (paper width direction).
The plate width is adjusted by moving the plate cylinder by the sideless motor 403B on one side of 5B, but a paper width adjusting mechanism is provided as in the case of the first embodiment. Example 1
In the case of, between the printing units, a dryer 120A, 1
While the temperature of the hot air of 20B was controlled to control the change amount of the paper width itself between the units applied to the paper, in the case of the multicolor printing machine 400 of the present embodiment, the temperature was adjusted. The temperature controller 421 for generating the wind and the fan motor 422 for sending the temperature-controlled wind are separately controlled to control the paper width.

Next, the data flow of the paper width control and the lateral register control in the multi-color printing press of the second embodiment will be briefly described with reference to FIG. 5 mainly by the printing unit 401B in FIG. Although the register controller 410 always recognizes the register, the recognized lateral register shift amount data is transmitted to the sidelet motor 403B, and the sidelet motor 403B sets the plate cylinder 402 by an amount corresponding to the shift amount.
Move B. On the other hand, the recognized lateral shift amount data is sent to the calculation unit 450, and the calculation unit calculates change condition data for the dryer 420A that matches the obtained shift amount data. The change condition data obtained by the calculation unit is sent to the sequencer 460 of the main unit, and the sequencer 460 of the main unit uses the temperature controller 421 and / or
Alternatively, predetermined condition change data is sent to the fan motor 422. Temperature controller 421 and / or fan motor 422
On the basis of the condition change data sent from the sequencer 460 of this machine, the temperature condition and the rotation speed of the fan motor are changed, and thereby the dryer 420A is set to a predetermined condition.

Next, the operations of the paper width control and the lateral register control in the multi-color printing press according to the second embodiment will be briefly described with reference to FIG. First, the printing unit 401 shown in FIG.
Detection marks 405A, 4A printed by A, 401B
Both sides of 05B are constantly monitored by the detectors (optical sensors) 409a and 409b in the unit 401B to detect the lateral shift amount between the detection marks 405A and 405B on both sides. (S601) Next, the register change amount σ due to the paper width change is calculated from the shift amounts on both sides detected by the detectors (optical sensors) 409a and 409b. When the register change amount σ due to the paper width change is not zero, the calculation unit 450 determines the wind speed change amount of the dryer 420A necessary to correct the register change amount.
Calculated and calculated according to (Fig. 1). (S602) Next, it is determined whether or not the register change amount σ can be corrected only by the wind speed. (S603) When the register change amount σ can be corrected only by the wind speed, the wind speed is changed by the fan motor 422 (FIG. 1) and the wind speed of the dryer 420A is changed (S604), and next time the changed condition of the dryer 420A is used. The time t ₁ until the control is obtained by a predetermined arithmetic expression. (S605) Next, it is determined whether printing is completed. (S61
1) If the printing is not completed, it is continuously confirmed whether the time t ₁ until the next control, which is obtained previously, has elapsed. (S6
12) Then, after the lapse of time t ₁ , the process again proceeds to step S601. When the printing is completed, the control is terminated and terminated.
(S613)

On the other hand, when the register change amount σ cannot be corrected only by the wind speed, the calculation unit 4 determines the temperature change amount of the dryer 420A necessary to correct the register change amount σ due to the paper width change.
50 (FIG. 4), the obtained temperature change amount is calculated from the current dryer temperature value and the allowable lower and upper limit values of the dryer temperature to determine the register change amount σ only by changing the temperature of the dryer. Determine if it can be controlled. (S607) At this time, when the register change amount σ can be obtained only by changing the temperature,
The temperature of the dryer 420A is changed by the temperature controller 421 (FIG. 1) according to the calculated temperature change amount (S60
8) Based on the changed condition of the dryer 420A, the time t ₂ until the next control is calculated by a predetermined arithmetic expression.
(S605) Next, it is determined whether printing is completed. (S61
1) If printing has not ended, it is continuously checked whether the time t ₂ until the next control, which has been obtained previously, has elapsed. (S6
12) Then, after the time t ₂ has elapsed, the process proceeds to step S601 again. When the printing is completed, the control is terminated and terminated.
(S613) At this time, when the register change amount σ cannot be obtained only by changing the temperature, the predetermined temperature change amount and the wind speed change amount of the dryer to be changed are calculated and calculated by the calculation unit 450 (FIG. 4). (S609), the wind speed change of the fan motor 422 (FIG. 1) and the temperature controller 4 are performed according to the obtained temperature change amount and wind speed change amount.
After changing the temperature of 21 (FIG. 1) (S610), the time t ₃ until the next control is calculated by a predetermined arithmetic expression based on the changed condition of the dryer 420A. (S605) Next, it is determined whether printing is completed. (S61
1) If the printing is not completed, it is continuously checked whether the time t ₃ until the next control, which is obtained earlier, has elapsed. (S6
12) Then, after the time t ₃ has elapsed, the process proceeds to step S601 again. When the printing is completed, the control is terminated and terminated.
(S613)

Next, the arithmetic expressions used in the above control flow will be described. Examples of basic arithmetic expressions include the following expressions (1) and (2). ΔF = Ae · hDTS (1) ΔT = Ae · hDFS (2) where ΔF is the fan motor rotation speed change amount of the dryer 420A, ΔT is the temperature change amount of the dryer 420A, e is the misregistration amount due to the paper width change, and h is A constant related to paper width,
D is a constant related to the path length of the dryer 420A, T is a constant related to the current temperature of the dryer 420A, F is a constant related to the current fan motor rotation speed of the dryer 420A, and A is a coefficient.

Further, in order to obtain the time until the next control, that is, the control cycle t, according to the changed condition of the dryer 420A, for example, the following equation (3) is used. t = k (HΔD + PS) (3) where t is a control cycle, H is a constant related to the condition change of the dryer 420A, ΔD is a condition change amount of the dryer 420A, P is a constant related to the path length between printing units, and S is a line. A constant related to speed, and k is a coefficient.

In the multi-color printing press of the second embodiment, if it is desired to increase the control by the wind speed (air volume) rather than the temperature in order to perform more flexible paper width control, the air volume setting is allowed at the same time when the temperature is changed. This can be achieved by having the control flow change to the median of the values.

In the multi-color printing presses of Examples 1 and 2, the detection mark printed by each printing unit was used to detect the change in the paper width, but the method is not limited to this. Not done. A displacement sensor or the like may be used.
Regarding the change in the paper width, the amount of change in the paper width may be detected immediately before the printing in the preceding printing unit and immediately before the printing in the latter printing unit. Further, the detection marks printed on both sides of the paper in the preceding printing unit may be used to measure the distance between the detection marks on both sides.

In the multi-color printing presses of Examples 1 and 2, the change amount of the paper width itself is controlled by the temperature control of the dryer, or the temperature control of the dryer and the wind speed (air volume) control. Alternatively, the amount of change in the paper width itself may be controlled by controlling the humidity of the hot air of the dryer. The temperature, humidity, and air volume (air velocity) of warm air may be controlled at the same time. Further, in the multi-color printing press of the above embodiment, the paper width is controlled, but this method also makes it possible to control the width of materials other than paper. As such a material, the width can be controlled as long as it is a material that causes a dimensional change due to a change in water content or a material that causes a dimensional change due to a difference in heat amount.

As described above, in order to control the paper width, a method of controlling the warm air temperature and the air volume (air velocity) has been adopted, but the method is not limited to this. For example, a method of changing the length (path) of the hot air contacting the paper using a heat insulating material or the like may be used independently or in combination with the above method. The point is that the amount of heat applied to the paper can be controlled.

[0020]

According to the present invention, the paper width change is automatically and constantly corrected during printing, instead of being visually inspected by a person after the final printing unit (after full printing) as in the prior art. Therefore, there is almost no defect loss due to paper width change,
At the same time, the burden on the operator is reduced, and there are almost no mistakes due to adjustment. After all, defects due to paper width changes are eliminated and printing productivity is improved.

[Brief description of drawings]

FIG. 1 is a schematic diagram of a main part of a first embodiment of a multi-color printing press according to the present invention.

FIG. 2 is a flow chart of paper width control operation in the multi-color printing press according to the first embodiment.

FIG. 3 is a diagram illustrating a relationship between a detection mark and correction in the multicolor printing press according to the first embodiment.

FIG. 4 is a schematic view of the essential portions of Embodiment 2 of the multi-color printing press of the present invention.

FIG. 5 is a diagram for explaining a data flow of paper width control and register control in the multi-color printing press according to the second embodiment.

FIG. 6 is a flow chart of paper width control operation in the multicolor printing press according to the second embodiment.

[Explanation of symbols]

 100 Multicolor printing machine 101A, 101B Printing unit 102A, 102B Plate cylinder 103A, 103B Sideless motor 104A, 104B Paper (web) 105A, 105B Detection mark) 109a, 109b Detector (sensor) 110 Register controller 111 Damper controller 120 Dryer 121 hot air 122 cold air 123 damper 400 multi-color printing machine 401A, 401B printing unit 402A, 402B plate cylinder 403A, 403B sideless motor 404A, 404B paper (web) 405A, 405B detection mark 409a, 409b detector (sensor) 410 Controller 421 Temperature controller 422 Fan motor 450 Calculation unit 460 Sequencer of this machine

Claims (10)

[Claims] 1. A method for correcting misregistration due to a paper width change between printing units in a multi-color printing machine such as a gravure printing machine and an offset printing machine, which detects a paper width change between consecutive printing units, A paper width control method characterized in that the paper width is kept constant by controlling the hot air of a dryer applied between the printing units according to the detected paper width change. 2. The detection of paper width change between printing units according to claim 1, wherein the detection marks on both sides of the paper printed and provided in each printing unit are optically detected and detected. A paper width control method characterized by detecting a change in paper width from the position of a use mark. 3. The paper width control method according to claim 1 or 2, wherein the control of the hot air is control of the temperature and / or the air volume of the hot air. 4. The paper width control method according to claim 3, wherein the temperature control of the hot air of the dryer is performed by controlling a mixing ratio of hot air and cold air. 5. The paper width control method according to claim 4, wherein the control of the mixing ratio is performed by controlling the damper opening. 6. The paper width control method according to claim 3, wherein the temperature control of the hot air of the dryer is performed by controlling gas heating. 7. A means for detecting a paper width change between at least continuous printing units, and a paper width is controlled between the printing units by controlling hot air of a dryer applied to the paper in accordance with the detected paper width change. A multicolor printing press, characterized by having a means for keeping it constant. 8. A multi-color printing press according to claim 6, wherein the control of the hot air is control of the temperature and / or the air volume of the hot air. 9. A multicolor printing press according to claim 7, wherein the temperature control of the hot air of the dryer is performed by controlling the mixing ratio of the hot air and the cold air. 10. A multi-color printing press, wherein the control of the mixing ratio according to claim 8 is performed by controlling a damper opening degree.