JPH09300578A - Method for adjustment of reference phase of plate cylinder and plate cylinder used therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the time required for the whole early registering process by using a plate cylinder with supporting shafts provided on both sides and a center of gravity deviated from the axial center position, then mounting the supporting shafts of the plate cylinder on the bearing part of a printer and further, rotating the supporting shafts in natural way so that the heavier one is located below the other to match the phase of each of the plate cylinders. SOLUTION: A plate cylinder 10 has an end face member 13 which blocks the end face of a tube-like cylindrical part 11 and fixes supporting shafts 12 to the cylindrical part 11, and a weight 14 is attached to the outside of the end face member 13 by a means such as a screw. In addition, the pictorial pattern of each of plate faces on each of the plate cylinders with a varying color is formed in its own direction of the center of gravity as a reference. A made-up gravure plate cylinder 10 is set in such a manner that the supporting shafts 12 on both sides are mounted on the bearing part of a printer respectively. In this case, she weight 14 is naturally rotated downward, if the weight 14 is not at right below porition, so that the part of the weight 14 comes directly below. Thus, the rotary position of each of the plate cylinders with a varying color is decided and consequently the phase of each of the plate cylinders 10 is matched to perform the reference position adjustment.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an initial register adjustment in a multicolor gravure printing machine, and more particularly to a method for adjusting a reference phase of a plate cylinder in the initial register adjustment and a gravure plate cylinder used in the method.

[0002]

2. Description of the Related Art In order to produce a printed matter by printing multicolor patterns by multicolor gravure printing, usually one color is overlaid to form one pattern. In this case, it is necessary to properly align the colors so that there is no misregistration such as overlapping printing of each color or a margin between the colors. Control adjustment means are provided.

Now, the register adjustment by the register adjusting device will be described with reference to FIGS. 4 to 6. FIG. 4 is an explanatory view showing a register adjustment mark and a plate cylinder on the running paper, FIG. 5 is an explanatory view showing a register adjustment method between two color printing units, and FIG. 6 is a registration between all units of a multicolor printing machine. It is explanatory drawing which provided the adjuster.

The register adjusting device is a register for four colors printed by the plate cylinders 30a to 30d (assuming a four-color machine here) at regular intervals for each color in the margin of the print pattern on the running paper 20. The adjustment marks 21a to 21d are set on the plate cylinders 30a to 30
Scanning heads 40a-4 provided downstream of 0d
0d, the register adjustment marks 21a to 21d for four colors are provided between the plate cylinders 30a to 30d so that the four color registration adjustment marks 21a to 21d are always printed at regular intervals during printing.
The positions of 5a to 25c are moved. Note that the register adjustment marks 21a to 21d on the running paper 20 correspond to the plate cylinders 30.
Register adjustment marks 31a to 31d formed on a to 30d
The register adjustment marks 21a are printed on the running paper 20 at a constant pitch (here, the plate cylinders 30a to 30d are provided with the register adjustment marks 31a to 31d, respectively). Therefore, they are sequentially printed with the circumferential length of the plate cylinder 30a).

As shown in FIG. 5, immediately after the second color plate cylinder 30b, the first and second color registration adjustment marks 2 of the running paper 20 are printed.
A scanning head 40a for detecting 1a and 21b is provided. Further, a compensator roller 25a is provided so that registration can be performed by changing the distance between the printing points of the running paper 20 between the first-color plate cylinder 30a and the second-color plate cylinder 30b. The scanning head 40a has mark detection elements 41a, 41a, 21a, 21b at the same intervals in the traveling direction of the running paper 20 as the registration adjustment marks 21a, 21b.
41b is arranged. Of these, the mark detection element 4
Reference numeral 1a is for detecting the first color register adjustment mark 21a, and mark detection element 41b is for detecting the second color register adjustment mark 21b.

[0006] Here, if the 1 and 2 colors are in register,
Since the first and second color register adjustment marks 21a and 21b are printed at the same intervals as the scanning head mark detecting elements 41a and 41b, the mark detecting elements 41a and 41b detect the register adjusting marks 21a and 21b at the same time. However, if the registrations are misaligned, there is a time difference between the mark detection elements 41a and 41b in detecting the registration adjustment marks 21a and 21b. Based on this time difference, the register adjuster main body 42
The movement amount of the compensator roller 25a is calculated. Then, the compensator roller 25a is moved so that the register adjustment marks 21a and 21b have a predetermined interval, and control is performed so as to match the register.

The register adjuster provided between all units of the multicolor printing machine is shown in FIG. 6, where:
Scanning head 40a immediately after the second-color plate cylinder 30b
Detects the first and second color register adjustment marks 21a and 21b and controls the first compensator roller 25a. Also, the scanning head 4 immediately after the third-color plate cylinder 30c
0b detects the second and third color register adjustment marks and controls the second compensator roller 25b. That is, the scanning heads 40a, 40b, 40c detect the register adjustment mark, and the gates 43a, 43 are added to the detection signals.
A predetermined gate is applied from b and 43c to the register adjusting units 44a, 44b and 44c. Subsequently, in response to signals from the register adjusting units 44a, 44b, 44c, the compensator roller position controllers 45a, 45b, 45c are used to drive the compensator rollers 25a, 25b, 25c.
Is controlled.

In the above-described multicolor printing machine, the register adjustment marks 21a to 21d of each color are generally arranged at intervals of about 20 mm. In addition, each scanning head 40
a, 40b, 40c are not confused with other marks,
The signals from the scanning heads 40a, 40b, 40c are gated so that only predetermined register adjustment marks can be detected.

The register adjustment device automatically adjusts the register on the machine during printing. To perform the automatic register adjustment during the actual printing, the register adjustment is performed by performing the initial register adjustment described later. It is necessary to complete the setup of the device. Specifically, in a conventional gravure printing machine or the like, the pitch of the printed matter matches the length of the circumference of the plate cylinder used (hereinafter referred to as the plate cylinder circumference value), and the plate cylinder circumference value is Since the item changes every time the item is switched, that is, each time the plate cylinder of the next item is replaced, when the plate cylinder of each printing unit is replaced by a new plate cylinder of the next item, each scanning head 40a, It is necessary to adjust so that 40b and 40c can almost detect only the predetermined register marks printed by the new plate cylinder through the new pitch.

The initial register adjusting method will be described with reference to FIGS. 7 and 8. Here, for convenience, three colors will be described.

As shown in FIGS. 7 and 8, each plate cylinder 3 is previously prepared.
On the non-pattern surface of 0a, 30b, 30c, registration marks visual marks 32a, 32b, 32c are provided at the same position (which may be expressed as the same phase because they are cylindrical) with respect to the pattern to be printed.
(It is called a registration mark, but this time it is called a reference mark). Then, at the time of the switching work, after replacing with the new plate cylinders 30a, 30b, 30c of the next item, and by aligning the reference marks 32a, 32b, 32c of the plate cylinders with the same position for each printing unit, each printing is performed. Each plate cylinder 30a, 3 with respect to the drive shaft of the unit
0b and 30c are predetermined phases (hereinafter referred to as reference phases)
The so-called reference phase adjustment is performed according to. In FIG. 8, the reference marks 32a, 32b, 32c are shown on the plate cylinders 3 respectively.
0a, 30b, and 30c are drawn on the side surfaces to explain that the reference marks face the same phase. Actually, as shown in FIG. 7, the respective plate cylinders 30a and 30c.
It is provided on the non-pattern portion at the end on the circumferential surface side of b and 30c.

Next, the positions of the compen center rollers 25a and 25b are adjusted so that the patterns printed on the running paper 20 by the respective plate cylinders 30a, 30b and 30c are in register (meaning that the reference marks match). adjust. That is,
Since the reference phase adjustment of the plate cylinders 30a, 30b, 30c has been completed in advance, for example, the distance of the running paper 20 between the contact point (printing point) of the first color plate cylinder 30a and the impression cylinder 26a is Three
So-called paper path adjustment is performed to adjust the positions of the compensating center rollers 25a and 25b so as to be an integral multiple of the plate cylinder circumference value of 0a, 30b, and 30c.

Finally, the register adjuster 42 performs a so-called gate adjustment for applying a gate to the detection signal of the scanning head for each register adjustment mark of each color, completes the initial register adjustment, and completes the initial register adjustment. In this state, each scanning head can almost detect only a predetermined register mark.

As described above, in the conventional gravure printing machine or the like, each time the printing item changes and is replaced with a new plate cylinder of the next item, the initial register adjustment, that is, the reference phase adjustment of the plate cylinder and the inter-print unit are performed. It is necessary to adjust the web path and the gate of the register adjuster.For the web path adjustment between the printing units among these operations, enter the plate cylinder circumference value to calculate the proper position of the compensating center roller. The current printer has a mechanism that automatically adjusts the position, and the register adjuster automatically adjusts the gate position for the gate adjustment of the register adjuster. However, at present, the worker is manually performing the reference phase adjustment of the plate cylinder.

The reference phase adjustment of this plate cylinder is performed in the following procedure. First, the plate cylinder is placed on the bearing portion of the printing unit. Next, the operator manually rotates the plate cylinder to stop the reference mark provided on the peripheral surface of the plate cylinder so that the reference mark is located at a predetermined position using a level or a laser pointer as an auxiliary tool. Next, the internal clutch is operated to connect with the driving shaft of the printing press. This manual work is carried out individually by each worker for all printing units.

FIG. 9 is a schematic view showing an example of the reference mark of the plate cylinder mounted on the printing unit after adjusting the reference phase. In FIG. 9, 50 is a plate cylinder (gravure plate cylinder),
Reference numeral 51 is a reference mark, 52 is a coupling clutch, and 53 is an internal clutch, and the reference mark faces the front side (horizontal direction of the plate cylinder center). Further, FIG. 10 shows a laser pointer (a side of A) used as an auxiliary tool for alignment.
It is a figure showing the level and the level (the side of B), and in the figure,
61 is a laser pointer, 62 is a level, and 63 is a line shaft (driving shaft).

[0017]

According to the method for adjusting the reference phase of the plate cylinder by such means, since the alignment is performed by the operator, the accuracy of the phase adjustment is poor, and the work requires an operator and cannot be automated. There was a problem.

The present invention has been made in view of the above problems, and an object thereof is to adjust the reference phase of the plate cylinder in the initial register adjustment and to mount the plate cylinder on the printing machine. It is an object of the present invention to provide a method for adjusting a reference phase of a plate cylinder, which is performed only by performing it without manpower or machine operation, and a plate cylinder used for the method.

[0019]

In order to achieve the above object, the method for adjusting the reference phase of a plate cylinder according to the present invention adjusts the plate cylinder to the reference phase with respect to the driving shaft in the initial register adjustment of the gravure printing machine. A phase adjustment method, in which a plate cylinder having support shafts on both sides and a center of gravity deviated from the axial center position is used, the support shafts on both sides of the plate cylinder are respectively placed on the bearings of the printing machine. It is characterized in that the respective plate cylinders are phase-aligned by rotating them naturally so as to face downward.

That is, by using a plate cylinder having support shafts on both sides and having a center of gravity deviated from the axial center position in a predetermined direction, the reference phase of the plate cylinder can be utilized by utilizing universal gravitational force without manpower or machine operation. Adjustment can be done naturally

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an example of a plate cylinder used in the present invention. FIG.
(B) is a side view.

The plate cylinder 10 shown in this example is provided with an end face member 13 which serves to close the end face of the cylindrical body portion 11 and to fix the support shaft 12 to the body portion 11. A weight 14 made of a metal plate is attached to the outside by means such as screwing. Therefore, the center of gravity of the plate cylinder 10 is not in the axial center position and is displaced in the direction of the weight 14.

The unbalanced plate cylinder 10 is used in each printing unit of the gravure printing machine. In the plate cylinder 10 of each color, the pattern on the plate surface is formed with the direction of the center of gravity as a reference. Specifically, when the unbalanced plate cylinder 10 is made into a plate-made gravure plate cylinder (printing plate), the phase reference in the axial rotation direction of the pattern is performed in the direction of the center of gravity. For all gravure plate cylinders used in multicolor printing, the same direction of the center of gravity is used as the phase reference. When the gravure plate cylinder is attached to the plate making device, the gravure plate cylinder is naturally rotated so that the heavier side is the same as the case where the gravure plate cylinder is attached to the printing unit. Alternatively, a reference mark is provided in advance on the circumferential surface of the gravure plate cylinder with reference to the direction of the center of gravity,
After mounting the gravure plate cylinder on the plate making apparatus, plate making is performed by using the mark as a phase reference. The gravure plate cylinder thus plate-made is usually stored in a warehouse and is carried out to a printing machine according to a printing plan. The gravure plate cylinder is carried out by a plate cylinder carrier. Further, the gravure plate cylinder 10 of the plate cylinder carrier is set so that the support shafts 12 on both sides are respectively mounted on the bearings of the printing machine by a transfer means such as an automatic mounting device or a manually operated crane. . At this time, as shown in FIG. 2 (a), if the weight 14 is not directly below when placed on the pair of bearings 15 in the printing machine, the heavier one naturally rotates so that the heavier one is downward due to the law of universal gravitation. As shown in FIG. 2B, one with the weight 14 is located directly below and settles down. By thus determining the rotational position of the plate cylinder 10 for each color, the phases of the plate cylinders 10 are matched and the reference phase adjustment is performed.

3A and 3B show another example of the plate cylinder used in the present invention. FIG. 3A is an end view thereof, and FIG. 3B is a sectional view of the vicinity of the end.

The plate cylinder 10 shown in this example is provided with the end face member 13 that serves to close the end face of the cylindrical body portion 11 and fix the support shaft 12 to the body portion 11 as described above. Same as, but with different weight attachment. That is, in the plate cylinder 10 of this example, a hole is formed in the end surface member 13, and a weight 16 made of a piece having a large specific gravity is provided in the hole.
Are integrally fixed by welding or shrink fitting.
In the case of this plate cylinder 10 as well, the center of gravity is displaced in the direction of the weight 16 as described above, and when the support shafts 12 on both sides are placed on the bearings of the printing machine, the heavier side will be the lower side. It turns to the bottom, and the one with the weight 16 is directly below and settles down.

The imbalance of the plate cylinder has only to occur when the plate cylinder is mounted on the printing machine, and thus the weight as described above may be removable from the plate cylinder. Further, if an imbalance occurs in the plate cylinder, it is also possible to adopt a means such as partially increasing the wall thickness of the drum portion without attaching a weight.

[0027]

As described above, according to the present invention,
Since it is possible to adjust the reference phase of each plate cylinder naturally without manual work or machine operation when mounting the plate cylinder, it is possible to reduce the time required for the entire initial registration and to require skilled technology. . Further, since it is not necessary to use an auxiliary tool for plate phase alignment and only a slight additional work is required for the conventional plate cylinder, the process can be performed easily and inexpensively. Further, by automating the transfer of the plate cylinder to the printing unit, not only the plate cylinder exchange in the switching work but also the initial register adjustment can be automated.

[Brief description of drawings]

FIG. 1 shows an example of a plate cylinder used in the present invention,
(A) is a perspective view of the edge part vicinity, (b) is an end view.

FIG. 2 is an explanatory diagram showing a state of phase matching when the plate cylinder shown in FIG. 1 is used.

3A and 3B show another example of the plate cylinder used in the present invention, in which FIG. 3A is a perspective view of an end portion thereof and FIG. 3B is an end view thereof.

FIG. 4 is an explanatory view showing a register adjustment mark and a plate cylinder on a running paper.

FIG. 5 is an explanatory diagram showing a register adjustment method between two-color printing units.

FIG. 6 is an explanatory diagram in which a register adjuster is provided between all units of a multicolor printing machine.

FIG. 7 is an explanatory view showing a plate cylinder having a registration misalignment visual check mark (reference mark) and a running paper.

FIG. 8 is an explanatory diagram showing a state in which reference phase adjustment is performed.

FIG. 9 is a schematic diagram showing an example of a reference mark on a plate cylinder that is mounted on a printing unit through reference phase adjustment.

FIG. 10 is an explanatory view showing an auxiliary tool for alignment in its usage state.

[Explanation of symbols]

 10 Plate cylinder 11 Body part 12 Support shaft 13 End surface member 14 Weight 15 Bearing 16 Weight

Claims (2)

[Claims] 1. A phase adjusting method for adjusting a plate cylinder to a reference phase with respect to a driving shaft in initial register adjustment of a gravure printing machine, the plate cylinder having support shafts on both sides and having a center of gravity displaced from an axial center position. It is characterized in that the support shafts on both sides of this plate cylinder are placed on the bearings of the printing machine, respectively, and the plate cylinders are naturally rotated so that the heavier one is on the lower side, and the phase of each plate cylinder is adjusted. Method of adjusting the reference phase of the plate cylinder. 2. A plate cylinder for a gravure printing machine, which has support shafts on both sides and has a center of gravity deviated in a predetermined direction from an axial center position.