JPS637949B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an initial registration method performed prior to the start of printing in multicolor gravure printing.

By the way, the schematic structure of the gravure rotary press is as shown in FIG. In the figure, 10a,
b, c, and d are gravure cylinders corresponding to each color, for example, yellow, red, indigo, and black; 12 is an impression cylinder; 14 is a doctor blade; 16 is an ink pan; and 18 is printing paper. Further, 20a, b, c are compensator rollers, and 22a, b are compensator rollers 2 during printing.
This is a detector that obtains a signal for driving 0. The compensator roller is primarily used to perform registration operations after the start of printing.
For example, the detector 22a detects a yellow mark and a red mark, the detector 22b detects a red mark and an indigo mark, and so on. The compensator rollers 20a and 20b are moved up and down to compensate for registration.

Here, in gravure printing, the plate making is performed using the cylinder as a whole, so the cylinder 10 is detachable from the printing machine. The attachment/detachment mechanism for this purpose is shown in Figures 2 and 3.

In FIG. 2, 26 is the shaft of the cylinder 10, 28 is a coupling, 30 is a worm gear,
332 is a line shaft to which the worm 34 is fixed. Serrations are formed on the shaft 26 and the coupling ring 28 so as to be detachable. Third
The figure shows other mechanisms, including cylinder shaft 3.
6 and the coupling ring 38 are connected by tightening a screw 40 as shown in FIG.

As described above, in gravure printing, since the cylinder itself can be attached to and detached from the printing machine, an initial registration operation is required prior to starting printing. Initial registration refers to eliminating the phase difference between the cylinders that occurs when the cylinders are installed, and in the case of a printing press equipped with the attachment/detachment mechanism shown in the second figure, the phase between the cylinders is adjusted visually by the operator, and the installation After that, it is difficult to make fine adjustments due to the serration connection, so move the compensator roller 20 from the zero point position (intermediate position) to another position to adjust the phase difference between the cylinders to the running length of the printing paper between each cylinder. I try to get rid of it even with changes. However, the amount of movement of the compensator roller is extremely roughly determined; for example, the distance from the edge of the ink pan 16 to an appropriate reference position such as the register mark print area 24 or registration mark is measured using a ruler, and then the distance between each cylinder is determined. The compensator roller is moved based on the phase difference between the two.

Furthermore, in the case of a printing press equipped with the attachment/detachment mechanism shown in FIG. 3, the cylinder 10 can be rotated even after the cylinder is attached, so that the gauge 4 shown in FIG.
2 is used to match the phases between the cylinders. In the figure, 44 is a member of the printing press provided near each cylinder, 46 is a magnet, and 4
8 is a bar fixed to a magnet. This gauge 42 is applied to each cylinder, and the cylinder 10 is rotated so that the tip of the rod 48 matches the mark 24 on the cylinder.
The screws are tightened.

However, as is clear from the above explanation, in both the former and latter methods, the phase difference between each cylinder is determined based on the ink pan 16 or the frame member 44, etc., and these standards are Since the positions of the printing units are not mutually constant, large errors naturally occur in the measurement of the phase difference, and even if the initial position of the compensator roller 20 is adjusted, misregistration may occur at the beginning of printing. A lot of paper is produced. These misregistrations are gradually eliminated by the compensating device, but the present invention aims to further reduce the occurrence of paper waste before a good response from the compensating device can be obtained.

That is, in the present invention, in order to more accurately measure the phase difference between each cylinder, the reference position is selected on a horizontal plane that is unified among the cylinders, and the deviation from this reference position to the reference position of each cylinder is measured. Based on this, the initial position of the compensator roller is adjusted.

Hereinafter, embodiments of the present invention will be further described using FIGS. 6, 7, and 8.

FIGS. 6 and 7 show a phase measuring tool for each gravure cylinder. The measuring device consists of a curved member that conforms to the surface of the cylinder 10 and means for setting the curved member in a particular horizontal position. In this case, the curved member consists of a side plate 50 which is curved on one side and a transparent plate 52 fixed to the curved part. The lower ends of both side plates 50 are fixed by horizontal plates 54. If both side plates 50 can be firmly fixed with the horizontal plate 54, the transparent plate 52 may not be provided.

Further, the horizontal position setting means may include, for example, a spirit level 5.
It is 6. In this case, the spirit level 56 is fixed to the horizontal plate 54.

Therefore, by bringing the curved member into contact with the surface of the cylinder 10 as shown in FIG. 8, and moving the entire measuring tool up and down while watching the level 56, the curved member can be placed at a specific horizontal position in relation to the cylinder surface. Can be set.

In addition to a level, the horizontal position setting means can be
A mark is provided on the straight line extending from the curved member, for example, on the side edge 58 of the horizontal plate 54, and a string with a weight attached is suspended from the side plate 50. When the string matches the mark, the horizontal plate 5
4 can also be made horizontal.

As described above, when the phase measuring tool is held horizontally, a desired point of the measuring tool is set as the reference position, and from there, a common reference position on each cylinder surface, such as the easily distinguishable drawing area, the register mark printing area 24 , the deviation to the registration mark mark area, etc. is determined. The deviation can be expressed in terms of length, angle, etc., and in order to read them, a transparent scale plate 60 is provided as shown in FIGS. 6 and 7. The scale plate 60 is a structure 6 provided on the side plate 50.
2 and is slidable along the side plate 50. Therefore, even if the specific horizontal position of the measuring instrument is far away from the reference position of the cylinder, it is possible to measure the deviation by pulling out the scale plate 60.

In addition, if there is no such problem, the scale plate 6
0 can also be replaced by the transparent plate 52. Furthermore, the side plate 50 can also be used instead.

Further, the reference position of the measuring tool can also be set using a cursor 64 as shown in FIGS. 6 and 7. The cursor 64 is also provided so as to be able to slide within a groove 66 provided in the side plate 50. In this case, the operator first determines the deviation between the horizontal position and the reference position of the measuring tool for the yellow cylinder 10a, slides the cursor 64 to the reference position 24a on the cylinder side and fixes it there as the reference position, Then red, indigo,
The horizontal positions of the black cylinders 10b, c, and d are set in the same manner, and the reference position 24 of each color cylinder is set.
The difference between b, c, and d and the reference position at which the cursor 64 stops is determined.

The initial position of the compensator roller 20 is adjusted based on the thus measured deviation, thereby changing the traveling path length of the paper 18 between the gravure cylinders of each color and eliminating the phase difference between the gravure cylinders of each color. become.

As described above, the present invention provides a phase measuring device having a curved member that matches the surface of the gravure cylinder and a means for setting the curved member at a specific horizontal position, to each color of the gravure cylinder installed in the printing press. The measuring tool is applied and held at a specific horizontal position, the deviation from the reference position of the measuring tool to the reference position of each cylinder surface is determined, and the initial position of the compensator roller is adjusted based on this deviation.

Therefore, according to the present invention, it is possible to accurately grasp the phase difference between the gravure cylinders of each color, so the initial position of the compensator roller can be set quite strictly and the length of the printing paper running path between the cylinders of each color can be adjusted. Therefore, the cylinder phase difference can be virtually eliminated. Then, it is possible to obtain a printed matter that is properly registered to some extent from the start of printing, and it is possible to reduce the occurrence of paper waste that occurs until a response from the compensating device is obtained.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a gravure rotary press.
FIG. 2 is a front view of an example of a gravure cylinder attachment/detachment mechanism, FIG. 3 is a front view of another example, and FIG. 4 is a sectional view taken along the line -- in FIG. FIG. 5 shows a conventional gauge used in cylinder phasing operations. FIG. 6 is a perspective view of an example of the phase measuring device used in the method of the present invention, and FIG.
FIG. FIG. 8 is a perspective explanatory view during phase measurement. 10... Gravure cylinder, 16... Ink pan, 18... Printing paper, 20... Copensator roller, 24... Printing area for register mark printing, 50...
Side plate, 52...Transparent plate, 54...Horizontal plate, 56...
...Level, 60...Scale plate, 64...Cursor.

Claims (1)

[Claims] 1. An initial registration method in gravure printing comprising the following items. a) A phase measuring device having a curved member that matches the surface of the gravure cylinder and means for setting the curved member at a specific horizontal position is applied to the gravure cylinder of each color installed in the printing machine and set at the above specific horizontal position. (b) Adjust the initial position of the compensator roller based on the above deviation to eliminate the phase difference between the gravure cylinders of each color; (2) The horizontal 2. A method according to claim 1, wherein the position setting means is a spirit level. 3. The method according to claim 1, wherein the horizontal position setting means is a straight line mark provided on the curved member and a string attached with a weight. 4. The method according to claim 1, wherein the deviation is determined from a scale carved on the curved portion.