JPH1148458A - Automatic register adjusting method in multicolor printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To automatically perform the rough adjustment and fine adjustment of the registering of a multicolor printer. SOLUTION: In this automatic register adjusting method, the register marks of respective patterns applied to continuous paper 2 by multicolor printing are photographed by a camera and, on the basis of the photographing signal, the registering of respective printed parts 1a-1e of respective colors is performed through a printing register adjusting means for the respective printed parts in a control apparatus. In this case, the register marks 11a-11e of respective patterns are photographed by a line camera 7 and the centroid positions of the respective register marks are calculated on the basis of the photographing signal not only to allow the cetroids of the respective register marks to coincide with each other but also to move the register marks to the predetermined positions with respect to a printing reference point to perform rough adjustment and, subsequently, the roughly adjusted register marks are photographed by an area camera 8 and, on the basis of this photographing signal, fine adjustment is performed so that the centroid positions of the respective register marks coincide perfectly with each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multicolor printing form printing machine, in which each register mark printed by each printing unit is imaged by a camera, and automatically controlled by a control device based on the image signal. The present invention relates to an automatic register adjustment method for registering.

[0002]

2. Description of the Related Art In a conventional automatic register adjustment method using a camera of this type, one area camera is used, and a limited field of view by this one area camera, for example, 15 mm is used.
A registration mark is captured within the corner, the amount of misregistration of the other color with respect to the reference color and the direction of misregistration correction are detected for each color, and based on the detection result, the plate cylinder of each color is moved, and Eliminating misregistration matches the register of all colors.

In this case, the register mark is, for example,
In the case of four-color printing, as shown in FIG. 1, two opposing circles on an intersection of eight equal angles on the circumference are marked as one color, and are placed in the 15 mm square camera field of view. The circles are evenly arranged on the circumference to recognize that they are in register. Note that this register mark is small enough to be inconspicuous even if it enters the picture, for example, a diameter of 2 mm
A circle having a diameter of 0.3 mm is arranged on the circumference of the circle.

[0004]

In the case of a multi-color form printing machine, when the plate cylinder is replaced due to size change or the like,
It is necessary to make a rough adjustment so that the registration marks of each color converge in the inspection area within the field of view of the camera. Conventionally, however, this rough adjustment has to be performed manually by an operator. As the time becomes longer, the number of waste sheets increases, and there is a problem that the production efficiency does not increase.

SUMMARY OF THE INVENTION The present invention has been made in view of the above, and has been made in consideration of the above-described problems, and has been made in consideration of the above-described problems. It is an object to provide an automatic register adjustment method.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, a method of automatic register adjustment in a multicolor printing press according to the present invention is provided in which a register mark of each pattern to be multicolor printed on continuous paper is imaged by a camera. Then, based on this imaging signal, in the automatic register adjustment method in a multicolor printing press that performs registration of each printing unit via the printing register adjustment unit of each color printing unit in the control device, the registration mark of each pattern is Take an image with a line camera, find the centroid position of each register mark with this image signal, match the centroid of each register mark, and move the register mark to a predetermined position with respect to the printing reference point to perform coarse adjustment Then, the roughly adjusted register mark is imaged by an area camera, and fine adjustment is performed by this image signal so that the centroid position of each register mark completely matches.

In the above-mentioned automatic register adjustment method for a multicolor printing press, a dumbbell with circles at both ends of a straight line is used as a register mark of each pattern, and horizontal, vertical and right inclinations are provided for each color. The image was printed with the posture changed to the left tilt.

Further, in the automatic register adjusting method in the multicolor printing press, among the register marks of the respective patterns, each of the register marks of the first to fourth colors is rounded at both ends of a straight line. The printing was performed by changing the orientation such as horizontal, vertical, right tilt, left tilt, etc. for each color, and the register mark of the fifth color pattern was made square.

[0009]

[Operation] The line camera scans over the entire width of the continuous paper and images the registration mark of each picture printed at an arbitrary position. Then, in accordance with an image signal picked up by the line camera, the plate cylinder of each picture is adjusted by the printing register adjusting means so that the register mark is roughly adjusted so that the centroid position of each register mark coincides. .

Then, the area camera takes an image of each of the coarsely adjusted register marks in the camera area thereof, and finely adjusts the centroid position of each of the register marks based on the image signal so that the centroid position of each register mark completely matches. .

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIG. In the figure, 1a, 1b, 1c, 1d, 1e
Is the first form printing machine to print five colors on continuous paper 2.
To a fifth printing unit, each of which comprises a plate cylinder 3 and an impression cylinder 4. Each of the cylinders 3 and 4 of each printing unit is connected to a drive source (not shown), rotates in synchronization with the running speed of the continuous paper 2, and the pattern of the printing plate mounted on each plate cylinder 3 is changed to each color. Is printed. Each plate cylinder 3 of each of the printing units 1a to 1e has a print register adjuster 5a, 5b, 5c, 5d,
In 5e, it is possible to move in the rotation direction and the axial direction.

A speed detector 6 for detecting a running speed of the continuous paper 2, a line camera 7 having an entire width of the continuous paper 2 as an imaging area, and a width direction of the continuous paper 2 downstream of the printing units 1 a to 1 e. , For example, the area camera 8 having an image pickup area on one side and outside the vertical perforation is connected to the continuous paper 2.
It is arranged to face. Reference numeral 9 denotes illumination for brightening the imaging surfaces of the cameras 7 and 8. Reference numeral 10 denotes a register adjustment control device, which includes a signal input circuit 10a, a comparison operation processing circuit 10b, a cpu 10c, and the like.

FIG. 3 shows the first to fifth printing sections 1a to 1a.
e, the first, second, third, fourth, and fifth register marks 11a, 11b, 11c, 11d, and 11e, of which the first to fourth register marks 11a to 11d are provided.
Has a dumbbell shape with circles at both ends of a straight line, and the fifth register mark 11e has a square shape. The first register mark 11a is, for example, horizontal (in the width direction of the continuous paper 2),
The second register mark 11b is vertical (the running direction of the continuous paper 2), the third register mark 11c is inclined to one side, and the fourth register mark 11d is inclined to the other side.

In each of the register marks 11a to 11e, the first to fourth register marks 11a to 11d are such that the first register mark 11a and the second register mark 11b are longer than the third register mark 11c. , The third register mark 11
The length of c is longer than the fourth mark 11d. The size of the fifth register mark 11e is larger than the circles provided at both ends of each straight line of the first to fourth register marks 11a to 11d.

Each of the register marks 11a to 11e
Is printed at a predetermined position with respect to the pattern printed by each of the printing units 1a to 1e, and when the respective register marks 11a to 11e are printed with their centroids coincident as shown in FIG. Each of the printing units 11a to 11e is in a state in which the register of the picture is aligned. Each register mark 11a
5 to 11e, for example, as shown in FIG. 5, is printed on one side in the width direction of the continuous paper 2 and outside the vertical perforations 2a, and the area camera 8 is opposed to this portion.
In addition, the line camera 7 scans over the entire width of the continuous paper 2 on the upstream side, thereby performing the registration marks 11a to 11c.
11e is detected.

Next, an automatic register adjustment method using the automatic register adjustment device having the above configuration will be described.

When five colors are printed on the continuous paper 2 by the printing units 1a to 1e, the register marks 11a to 11e are printed for each pattern of each color. At this time, if the respective patterns do not match, for example, they are slightly shifted sequentially in the running direction (and slightly shifted in the width direction of the continuous paper 2).
Then, the register marks 11a to 11e at this time are printed as shown in FIG. Each register mark 1 at this time
It is assumed that the printing areas 1a to 11e are larger than the imaging area of the area camera 8.

In this state, each of the register marks 11a to 11e
Is imaged by the line camera 7. Each register mark imaged by the line camera 7 is registered in the register adjustment control device 10.
And is recognized as position information in the running direction (and width direction) of the continuous paper 2 for each register mark. The running speed of the continuous paper 2 at this time is detected by the speed detector 6.

After the register adjustment control device 10 recognizes the shape and position information of each of the register marks 11a to 11e based on the input signal from the line camera, the centroids of the register marks 11a to 11e coincide with the printing reference position. Is calculated. At this time, for example, the first register mark 1
1a may be used as a reference.

The calculated numerical values of the corrected coordinates of the register marks 11a to 11e are output as movement signals (data communication or the like) to the print register adjusters 5a to 5e of the printing units 1a to 1e. As a result, the phase in the rotation direction and width direction of each plate cylinder 3 in each printing unit is moved in a direction converging toward a predetermined position with respect to the printing reference position, and is roughly adjusted. At this time, the registration accuracy becomes rough due to the resolution of the line camera 7.

Next, the area cameras 8 take images of the register marks 11a to 11e which have been moved to predetermined positions with respect to the printing reference position by the coarse adjustment. Each register mark imaged by the area camera 8 is input to the register adjustment controller 10 and recognized as position information for matching the centroid of each register mark.

After recognizing the shape and position information of each of the register marks 11a to 11e, the register adjustment controller 10 calculates corrected coordinates of each of the register marks 11a to 11e with respect to the printing reference position. And each of the calculated register marks 11
The numerical values of the corrected coordinates of a to 11e are sent to the print register adjusters 5a to 5e of the printing units 1a to 1e by moving signals (data communication and the like).
And the plate cylinders 3 of the printing units 1a to 1e are moved, and the register marks 11a to 11e are finely adjusted so that their centroids coincide as shown in FIG. At this time, since the resolution of the area camera 8 is higher than that of the line camera 7, precise adjustment is performed.

The register marks used in the method of the present invention are formed by using register marks 11a to 11d having circles at both ends of a straight line and a square register mark 11e, for example, as shown in FIG. Even in the case where the marks 11a to 11e overlap, the register adjustment can be performed in the resolution processing of the next imaging by the area camera 8.

[0024]

According to the present invention, the register adjustment in the multicolor printing is automatically performed, whereby the registration in the multicolor printing can be completely automated. The number of workers for the printing can be reduced, the printing preparation time can be shortened, and the waste paper can be reduced, and the production efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing an example of a conventional register mark.

FIG. 2 is a schematic structural explanatory view of an apparatus for carrying out the method of the present invention.

FIGS. 3 (a), (b), (c), (d) and (e) are register marks used in the method of the present invention.

FIG. 4 is an explanatory diagram showing a state in which the centroids of the register marks coincide with each other.

FIG. 5 is an explanatory diagram showing a state in which each register mark is printed on a continuous paper while being shifted.

FIG. 6 is an explanatory diagram showing an example of a state of a register mark roughly adjusted.

[Explanation of symbols]

1a, 1b, 1c, 1d, 1e: printing unit, 2: continuous paper,
3 ... plate cylinder, 4 ... impression cylinder, 5a, 5b, 5c, 5d, 5e ...
Print register adjuster, 6: speed detector, 7: line camera,
8 area camera, 9 illumination, 10 register control device, 11a, 11b, 11c, 11d, 11e register mark.

Claims (3)

[Claims] An image of a register mark of each pattern to be multicolored printed on continuous paper is taken by a camera, and based on the image pickup signal,
In the automatic register adjustment method in the multicolor printing press, in which the control unit registers each print unit through the print register adjustment unit of each color print unit, a register camera of each pattern is imaged by a line camera, and the image is taken. The centroid position of each register mark is determined by a signal, the centroids of the respective register marks are matched, and the register mark is moved to a predetermined position with respect to the printing reference point to perform a coarse adjustment. In a multi-color printing press, wherein an image is picked up by an area camera, and fine adjustment is performed by the image pickup signal so that the centroid position of each register mark completely matches. 2. A registration mark of each picture, which is formed in a dumbbell shape with circles at both ends of a straight line, and is printed in different orientations such as horizontal, vertical, right inclined, left inclined, etc. for each color. The automatic register adjustment method for a multicolor printing press according to claim 1, wherein: 3. Of the register marks of each pattern, each of the register marks of the first to fourth colors is formed in a dumbbell shape with circles at both ends of a straight line, and is horizontal for each color. ,
2. The automatic register adjustment method for a multi-color printing press according to claim 1, wherein printing is performed with the posture changed to vertical, right inclined, left inclined, etc., and the register mark of the fifth color pattern is made square.