JPH0315554A - Detection for registration in printing machine and its apparatus - Google Patents

Abstract

PURPOSE:To enable relative deviated amount among respective plate cylinders to be automatically detected by a method wherein an image data expressing a register mark is formed from a mark aggregate to be obtained by printing marks which are formed by shifting relatively positions on respective printing plates. CONSTITUTION:A register mark 1 which is an aggregate of marks M1 to M4 are printed on paper 2 by a series of printing processes. After printing, it is fixedly put on a sample stand 3 by an operator. A camera 4 being an imaging means is fixed to the sample stand 3 via a fixing angle 5 so as to image the register mark 1 on the paper 2 from its upside, and sends an image signal being the image data expressing the image register mark 1. A register deviation arithmetic part 6 inputs the image signal and calculates respectively distances (H1-H2, H1-H3, H1-H4, V1-V2, V1-V3, V1-V4) of other marks M2 to M4 to sides H1, V1 of the reference mark M1. At the same time, the register deviation arithmetic part 6 compares each calculated result with regular data, and calculates relative deviation of each mark M2 to M4 to the mark M1.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a register detecting device in a printing press, and is particularly useful when applied to registration work of each plate cylinder of a multicolor printing press.

BACKGROUND ART FIG. 3 is an explanatory diagram conceptually showing a six-color offset sheet-fed printing press. As shown in the figure, this printing machine 010 includes a paper feeding device 020, six stages of printing units 031, 082,
033, 034, 035, 036 and a paper ejection device 040. Each of the printing units 031 to 036 is equipped with a printing plate for printing, and includes a lithographic cylinder RH, and a rubber cylinder R, which is in contact with the plate cylinder RH and onto which images on the printing plates are transferred. And this rubber body R. and an impression cylinder RA that applies printing pressure in opposition to the cylinder RA.

The paper 050 sent out from the paper feeder 020 is transferred to the blanket cylinder R. and the impression cylinder RA to be printed and transfer cylinder Rl.
1 to the adjacent printing units 032 to 036. The paper 050 that has passed through the final printing unit 036 and has been printed in six colors is transferred to the paper discharge device 040 and stacked thereon.

In this series of printing steps, each printing unit 031 to 03
In step 6, a cross-shaped reference mark (register mark), for example, is printed on the paper 050 along with the picture, and each printing unit 03
It is used for the registration work of each plate cylinder RH of 1 to 036.

Registration work according to the prior art using the reference marks was performed in the following manner.

In other words, paper 05 on which six colors of printing have been completed in a series of printing processes.
An operator magnified and visually checked the reference marks printed over 0 using a magnifying glass, etc., and visually detected the relative deviation amount of each reference mark -3 -4-? , adjust each plate cylinder until these deviations are eliminated. Such misregistration can be adjusted for each of the printing units 031 to 086 by manually operating the registration device attached to each of the printing units 031 to 036, or by remotely operating the registration device using a remote control device. It is supposed to be done. Incidentally, if the registration is correct, each printing unit 031
The reference marks printed at ~036 completely overlap.

Problems to be Solved by the Invention> As described above, registration in the prior art involves adjusting the registration device based on the operator's intuition based on the amount of deviation observed by the operator visually checking the reference mark on the test-printed paper 050. Since each plate cylinder R was adjusted by operation, it was not possible to accurately detect the amount of deviation, and correction work was performed several times by trial and error until the register was perfectly aligned. For this reason, not only does the registration work take a lot of time, but also a lot of wasted paper is generated because test printing is performed every time correction is made. Also,
Since the registration work itself is a troublesome work of visually observing minute misregistrations, there is also the problem of causing great fatigue to the workers.

In view of the problems of the prior art described above, the present invention provides a method and device for detecting register in a printing press that can automatically detect the relative deviation amount of each plate cylinder of a printing press that performs multicolor printing. With the goal.

Means for Solving the Problems> The structure of the present invention that achieves the above object is as follows: A straight line extending in the vertical direction, which is the direction in which paper is transported in a printing press, and in the left-right direction, which is a direction perpendicular to this vertical direction. It is a set of marks obtained by printing marks on each printing plate of a multi-stage printing unit by relatively shifting the inscriptions on each printing plate on a single sheet of paper. A register mark is imaged by an imaging means to form video data representing the register mark, and then, based on the video data, distances between two similar sides of other marks with respect to two sides extending in the vertical and horizontal directions of the reference mark are determined. In addition to calculating the relative deviation between each printing plate, the distance between the two sides of the reference mark and the two sides of the other marks is compared with the above calculation result to calculate the difference between each printing plate. The relative deviation amount in the left-right direction and the vertical direction is calculated, and data representing each deviation amount is sent. It has two linear sides each extending in a certain left and right direction, and is printed on a single sheet of paper with marks formed on each printing plate of a multi-stage printing unit by relatively shifting the positions on each printing plate. A register mark that is a collection of marks to be obtained; an imaging means that images the register mark to form video data representing the register mark; Calculate the distances between two similar sides of other marks, and calculate the distances between the two sides of the other marks and the calculation results when the relative deviation between each printing plate is zero. The present invention is characterized by comprising a misregistration amount calculation section that calculates relative misalignment amounts in the horizontal and vertical directions between the printing plates by comparing the values, and sends out data representing each misalignment amount.

<Operation> According to the present invention having the above configuration, the paper flow direction of each printing plate (the direction in which paper is transported in a printing machine; referred to as the vertical direction) and the horizontal direction (direction perpendicular to the vertical direction) The relative deviation amount is the deviation amount between the marks printed by each printing unit in the register marks printed on the paper after a series of printing, that is, the deviation amount of each other mark with respect to one side of the reference mark in the horizontal and vertical directions. It is visualized as the amount of deviation of one side in the horizontal and vertical directions.

The imaging means takes an image of the register mark, and sends the video data to the misregistration amount calculating section. As a result, the misregistration amount calculating section calculates the relative misregistration amount based on the image data of the register mark, and sends out data representing each misregistration amount.

<Example> Embodiments of the present invention will be described in detail below based on the drawings.

FIG. 1 is an explanatory diagram showing register marks. As shown in the figure, this register mark 1 consists of a plurality of square marks M (four in this embodiment since four-color printing is performed).
, , M2, M3, and M4 are printed in the upper right margin of the printed paper.

Marks M and -M4 are printed one by one by four independent printing units for each color in a multicolor printing press, such as an offset four-color sheet-fed printing press similar to the printing press shown in Fig. 3, for example. Ru. That is, marks corresponding to the marks M1 to M4 are formed on each printing plate of each printing unit.

At this time, the marks formed on each printing plate are formed by relatively shifting the position on each printing plate by a predetermined amount, and as a result, the printing plate, that is, the plate cylinder, is in the correct position in each printing unit. In this case, the relative positions of the marks M, ~M4 printed sequentially by each printing unit are always constant (hereinafter, when the printing plate and plate cylinder are in the normal position, The mark M1 to M4 in this case is called the mark M1 to M4 in the normal position.
.

One side extending in the left-right direction of marks M1 to M4 is H, to H4.
, when a side extending in the vertical direction perpendicular to these H, ~H4 is v1 ~ V4, the marks M2 ~ M4 at the normal position in this example with the side H1V1 as a reference have the relationship shown in Table 1 below. There is.

In addition, in the same table, the length of one side of the XP marks M1 to M4 and α are the gaps between adjacent marks M1 to M4.

Table 1〉 Sokote, each side H2, V2~H,, V4 (7) side H,
, V, distance (H, -H2, H, -H,, H
, -H4, V1-V,, V, -V3, V, -V4)
! By calculating the relative deviation amounts in the vertical and horizontal directions of the marks M2 to M4 with respect to the mark M, by calculating the distance # between each side at the normal position (hereinafter referred to as normal data). I can do it.

Note that the shapes of the marks M1 to M4 are square, but
It is not limited to this shape.

Each of the marks M1 to M4 may have two mutually orthogonal sides extending in the vertical and horizontal directions. Also,
Since the above embodiment is a case of four-color printing, the marks M, -
Although four M are formed, it is obvious that this number can be increased or decreased in accordance with the number of colors, that is, the number of independent plate cylinders, in the same manner as in the previous embodiment.

FIG. 2 is a block diagram showing a target amount detection device according to an embodiment of the present invention together with a target device and a control section of the target device.

As shown in the figure, the paper 2 has a register mark 1, which is a collection of marks M1 to M4, printed on it through a series of printing processes. It was placed there. A camera 4, which is an imaging means, is fixed to the sample stand 3 via a fixed angle 5 so as to take an image of the register mark 1 on the paper 2 from above, and outputs a video signal which is video data representing the imaged register mark 1. Send out.

The misregistration amount calculation unit 6 inputs the video signal -11 and calculates the distance 113 m (}l, -H2, H,
-H,,H,-H4, V,-V2, V,-V,,
V, -V4) By performing G calculations and comparing the results of each calculation with normal data, each mark M2 to M
This is to calculate the amount of relative deviation of mark M1 of No. 4. More specifically, the misregistration amount calculation section 6 includes a binarization processing section 6a, a system controller 6b, and a CRT 6c.
, CRT controller 6d, program memory 6e,
Video data memory 〇f, communication interface 6gp
It has a 1/O controller 6h, an operation panel 61, and a printer 6j.

Among these, the binarization processing unit 6al binarizes the video signal sent from the camera 4 using the t gradation value set in advance by the operation panel 61 via the I/O controller 6h as a threshold, and Create value data. System CP
The U6b temporarily stores the plane binary data in the video data memory 61, reads out the plane binary data from the video data memory 6f, and displays it on the CRT 6c via the CRT controller 6d. As described above, the relative deviation amount of each of the marks M2 to M4 from the normal position in the vertical and horizontal directions is calculated using the mark M of the register mark 1 as a reference.

The relative shift amount calculated in this manner is displayed on the CRT 6c, printed on the printer 6j, and simultaneously sent to the control unit 7 via the communication interface 6g. The operation panel 6i is used to set various data such as the correspondence between printing units and marks M1 to M4, and to perform operations such as starting and stopping a series of processes of the misregistration amount calculating section 6. In addition, program memory 6
8 stores the processing procedure in the misregistration amount calculation unit 6.

The control unit 7 inputs data representing the relative deviation calculated by the registration deviation calculation unit 6 and performs predetermined processing, and then controls each printing unit via the registration device 8 so that the relative deviation amount becomes zero. Adjust the position of each plate cylinder. The control unit 7 of this embodiment has PQC (printing quali
ty control) equipment is used. Otsu's PQ
In addition to the register controller 7l that directly controls each register device 8, the C device has a dampening water controller 7h, a pressure point controller 7j, an ink feed controller 7k, etc., and although it is not directly related to register, it is used for printing. Wet water, pressure points, and ink feed, which have a significant impact on the quality of the ink, are controlled. In addition, in Figure 2, 7a is the main CPU
, 7b is a communication interface, 7c is a system interface, 7d is a memory, 7f is an operation panel, and 7g is a system interface.

The control unit 7 inputs each relative deviation amount corresponding to data representing each printing unit via the communication interface 7b, converts it into actual am data, and controls the registration device 8, thereby adjusting the amount of each printing unit. The phase of each plate cylinder is adjusted (correction of vertical deviation), and the phase of each plate cylinder in the axial direction of the cylinder is adjusted (correction of horizontal deviation).

The control unit 7 according to this embodiment has data on where the adjustment position of each registration device 8 is currently located, and collates this current position with data representing the relative deviation amount to determine the position as quickly as possible. , and the adjustment amount that is the closest to the center of the cylinder of each plate cylinder is calculated by the main CPU 7a, and each register device 8 is controlled via the register controller 7l.

That is, the relative misalignment amount of each printing unit supplied from the misregistration amount calculation section 6 to the control section 7 is calculated as D, D. , D,, D4
(The suffix D is the number of the printing unit, and the marks M, ~M4
), and if the current position data of the cylinders of each printing unit detected by the position detector of each printing unit that the control unit 7 has is P1"QI P3, P4, first add both data. Therefore, the data S, (=
D, 10P,), S2 (102+P2), S
Find 315-(=I)3,000P3), S, (1I)4,000F'4).

Next, the maximum value S mix and the minimum value Sml. , and the central value S. 1, is calculated.

S -S S =S --↓L11en2mld may 2S1~S4 and S
, nld, and SX,, SX2, Sx3, Sx4
The calculation is done.

sx,1s,+s,,d, SX2=82+S,,,,
sx3=s3+s,..., sx,=s4+s,,d The above calculations are performed by the main CPU 7a, and these data Sx1 to SX4 are sent to the target controller 7i. As a result, the register controller 7l outputs the data Sx1 to Sx1.
x4 is converted into actual control data, and the position of each plate cylinder is adjusted via each registration device 8.

The operation of this embodiment will be explained together with aspects of a series of registration operations.

First, by operating the operation panel 6l, the user inputs which printing unit the marks M, to M4 are to be printed in association with each other.

Next, the sample paper 2 on which the register mark 1, which is a collection of marks M1 to M4, is printed is placed on the sample stand 3.

For such a situation w. The video signal representing the register mark 1 captured by the camera 4 from 2 is sent to the binarization processing unit 6a and the CR.
Since the image is reproduced on the CRTBc via the T-controller 6d, the operator adjusts the position of the paper 2 so that the register mark 1 is approximately at the center of the screen of the CRT 6c while viewing the image on the CRT 6c.

After the position adjustment of the paper 2 is completed, by operating the "start" button on the operation panel 61, the following operations are executed in the misregistration amount calculating section 6.

That is, the binarization processing section 6 receives a command from the system CPU 6b.
a binarizes the video signal based on a threshold value preset on the operation panel 6i to form plane binarized data. The plane binarized data is temporarily stored in the video data memory 61 by the system CPU 6b, and is sent to the CRT 6c via the CRT controller 6d. As a result,
On CRT6c, plane 2 is displayed instead of register mark 1.
Display digitized data. Next, the system CPU 6b uses the algorithm described above based on FIG. 1 based on the plane binary data stored in the video data memory 6f.
The relative deviation amounts in the vertical and horizontal directions of the marks κ to M4 with respect to the mark M are calculated. Then the system CPU
6b issues a data communication request to the control device 7 via the communication interface 6g, and sends the relative deviation amount and the data of the printing unit to which this corresponds.

The control section 7, which has received the data on the amount of relative deviation and the printing unit to which it corresponds, operates the register w8 to adjust the misregistration of the plate cylinders between the printing units.

In the above embodiment, the data representing the amount of relative deviation computed and detected by the misregistration amount calculation unit 6 is sent to the control unit 7, and registration is automatically performed via the registration device w8. Based on the data representing the relative deviation amount detected by the deviation amount calculation unit 6 and printed out on the printer 6j, the operator can directly operate a control device such as a PQC device remotely, or the operator can directly operate the registration device. It is also possible to perform registration on site.

<Effects of the Invention> As specifically explained above in conjunction with the embodiments, according to the present invention, the amount of misregistration in the vertical and horizontal directions of the plate cylinder of each printing unit, which was conventionally checked visually, can be automatically and absolutely determined. Since it can be expressed as data, it is possible to quickly and accurately register the plate cylinder in the vertical and horizontal directions.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram for explaining a register mark according to an embodiment of the present invention and the principle of detecting the amount of misregistration using the register mark, FIG. 2 is a block diagram showing an embodiment of the present invention, and FIG. 1 is an explanatory diagram conceptually showing a six-color offset sheet-fed printing press. In the drawings 19-201, 1 is a register mark, 2 is a sheet of paper, 4 is a camera 1, 6 is a misregistration amount calculation unit, and M, M2, M3, and M4 are marks.

Claims (2)

[Claims] (1) Each printing plate of a multi-stage printing unit has two linear sides extending in the vertical direction, which is the direction in which paper is transported in a printing press, and in the left-right direction, which is a direction perpendicular to this vertical direction. A register mark, which is a collection of marks obtained by printing marks formed by relatively shifting the positions on each printing plate on a single sheet of paper, is imaged by an imaging means to form video data representing the register mark. Then, based on the video data, the distances between the two sides of the reference mark extending in the vertical and horizontal directions and the similar two sides of other marks are calculated, and the relative deviation amount between each printing plate is zero. By comparing the distances between the two sides of the reference mark and the two sides of the other marks with the above calculation results, the relative deviation amounts in the horizontal and vertical directions between each printing plate are calculated, and each deviation amount is expressed. A method for detecting an amount of stock in a printing press, characterized in that data is sent out. (2) Each printing plate of a multi-stage printing unit has two linear sides extending in the vertical direction, which is the direction in which paper is transported in a printing press, and in the left-right direction, which is a direction perpendicular to this vertical direction. A register mark is a collection of marks obtained by printing marks on a single sheet of paper by relatively shifting the positions on each printing plate, and a register mark is imaged and image data representing this register mark is generated. Based on the imaging means that forms the image and the video data, the distances between the two sides of the reference mark extending in the vertical and horizontal directions and the similar two sides of other marks are calculated, and the relative deviation between each printing plate is calculated. By comparing the distance between the two sides of the reference mark and the two sides of the other mark when the distance is zero with the above calculation result, calculate the relative deviation amount in the horizontal and vertical directions between each printing plate, and calculate each deviation. 1. A misregistration detection device for a printing press, comprising a misregistration amount calculation unit configured to send data representing the amount.