JPS6391252A - Registering method of offset printer and its device - Google Patents

Abstract

PURPOSE:To enable correct registering by comparing the related positions between registering marks of a trial print and a proof using a computer to obtain a deflection value and actuating a registering adjustment device based on the deflection value. CONSTITUTION:A proof is placed on a table 2 and the related positions between the centers of registering marks are input to a computer 21. Then a trial sheet is placed on the table 12, and the related positions between the centers of registering marks are input to the computer 21. After this, by comparison with the related positions between the centers of the registering marks of the proof, the computer 21 calculates a deflection value, and outputs a signal based on the deflection value to a registering adjustment device 22 of a printer for its actuation and registering operation. Consequently, no optical sensor for reading registering marks which calls for high-precision installation positioning is required in contrast to a conventional method in which such an optical sensor is required, and correct registering operating can be performed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention This invention relates to a method and apparatus for registering an offset printing press.

Conventional technology In modern offset printing, it is desired to shorten the setup time as the number of print runs decreases, and this setup time includes tasks such as plate changes, registration, and one-color matching. .

Various methods have been proposed in the past to shorten the registration time in these operations, but the typical one is the one shown in Figure WJ6, and we will provide an overview of this method. .

In this method, the printing plate 3 mounted on the first plate cylinder 30, 31
2. Burn registration marks 34°35 into 33 in advance,
The position of this mark 34, 35 is read by optical sensors 36, 37 during low-speed rotation before printing, and the top, bottom, left and right, and twist adjustment of the plate cylinder is adjusted by the nosol motor 39, 40 via the register adjustment device 38 of the first plate cylinder 32. This is what we are trying to do. Note that 41, 42, and 48 indicate proximity switches.

However, in such a method, the sensor 36,
The accuracy of the mounting position of 37 must be made to be suitably high, and to date, no satisfactory one has been provided.

The present invention eliminates the disadvantages of the conventional registration method as described above, and eliminates the need for an optical sensor for reading registration marks that can be used to accurately determine the mounting position.
It is an object of the present invention to provide a registration method and device that can achieve accurate registration.

Means for Solving Interset Points In order to achieve the above-mentioned object, the present invention writes register marks for each color in positions that do not overlap with each other on each color printing plate, and prints a proof print using these printing plates on a table. Place the test print on the table, store the center position of each register mark in the computer, remove the proof print, then place the test print on this table, find the center position of the register mark, and calculate the position between the centers. A computer compares the relationship with a previously stored positional relationship between the centers of the register marks to obtain a deviation value, and the computer operates a register adjustment device to correct this deviation value. be.

Furthermore, this invention achieves the above objects,
The registration device includes a table and a machine base having an image input camera installed horizontally movably above the table, a registration adjustment device for a printing press, and a computer, and the computer receives input from the camera. The center position information of each color register mark on the proof print is stored, and the center position information of each color register mark on the test print inputted from the same camera is compared with this stored information, the deviation value is calculated, and this deviation value information is stored. According to the present invention, the register adjustment device is operated to correct the deviation value.

Embodiment FIG. 1 shows an outline of an embodiment of the present invention, and in this embodiment, a pair of guide rails 8 are provided on both sides of the upright portion 3 on one machine l in a direction perpendicular to it. A support member 9 having both ends movable on the rail 8 in the Y-axis direction is provided above the table 2, and a pair of image input cameras Is#
-i It is previously installed on this support member 9 so as to be movable in the X-axis direction.

The support member 9 is provided with a pair of first pulse motors 6 for individually moving the camera 5 in the X-axis direction, and a second armature motor 7 for moving the support member 9 in the Y-axis direction. is set up.

In the computer 21 shown in FIG. 1, 23 is an information processing unit from the camera 5, and 24 is an information processing unit that inputs information from the processing unit 23, and based on the input information, register adjustment device 22
A storage unit that operates.

A control section consisting of a comparison section and a calculation section is shown, and 25 is a monitor television that monitors control operations.

The register adjustment device 22 may be completely similar to the conventional adjustment device 38, so detailed explanation thereof will be omitted.

A registration method performed by the above-mentioned registration device will be explained.

Figure 5 shows the method used for this registration method in a four-color machine.
An example of the register mark is shown, and 26.27° and 28.29 are those printed on the corner plate, the center plate, the peni plate, and the set plate, respectively, and when printed on printed matter, they become double paulownia. There are 6 different positions to ensure that nothing happens.

A proof sheet printed by the four printing plates for each color on which the register marks 26, 27, 28, 29 are printed is placed on the table 2, and the register marks 26, 27, 28 are printed on the table 2.
．． The movement of the support member 9 on the guide rail 8 and the X-axis or Y-axis of the camera 5 along the support member 9 so that 29 is in the field of view.
Due to the axial movement, the register marks 26, 27, 28 .
29 is read, its center position is determined, and this is processed by the processing unit 23.
and any selected one, for example, the center of the register mark 26 and the other register marks 27, 28, .
29 is stored in the control unit 24.

Then remove the proof from table 2.

Instead, place the test print on the table 2 and manually drive the Nors motor so that the register marks 26', 27', 28', and 29' (not shown) are in the field of view of the camera 5. Move the print. In this way, the center positions of the register marks 26', 27', 2 B', and 2G' are determined using the camera 5, and the following register marks 26, 27, 28°29
The same process as for register mark 26 is performed.
' center and the other register mark 27'.

The positional relationship between the centers of 28' and 29' is input to the control unit 24, and the control unit 24 compares this with the previously stored positional relationship between the register marks 26, 27, 28, and 29. , the amount of deviation between the two is determined.

The deviation value signal obtained in this manner is output from the control section 24 to the register adjustment device 22.
Based on this signal, the plate cylinder is adjusted vertically, horizontally, and torsionally in the same manner as in the conventional system.

Effects of the Invention This invention is as described above, in which a proof print is placed on a table, the relative position between the centers of each registration mark is recorded on a computer, and then a test print is placed on the same table. , input the relative position between the centers of each register mark on this test print into a computer, compare it with the relative position between the centers of the register marks on the proof print, and calculate the amount of deviation. A signal based on the deviation value calculated by Nt is input from the computer to the register adjustment device of the printing press, which is activated to perform registration. This has the effect of allowing extremely accurate registration, compared to the conventional method in which accurate registration was difficult due to the need to provide a senna and the difficulty in accurately positioning the senna.

[Brief explanation of the drawing]

#I1 is a schematic diagram of an embodiment of the invention, Figure 2 is a slope view of the machine base of the same as above, Figure 3 is a plan view of the same as above, Figure 4 is a front view of the same as above, and Figure 5 is a register mark. FIG. 6 is a perspective view of a conventional registration device. l...Machine 2...Table 5...Camera for image input 21...Computer 22...Register 1tui device 26.27.28.29...Register mark on proof sheet Patent applicant Sumitomo Heavy Industries Ltd. Figure 3, 3 Figure 4

Claims (1)

[Scope of Claims] 1. In multicolor printed matter, registration marks for each color are written on printing plates for each color so that the registration marks do not overlap each other, and proofs are printed using these printing plates. Place the print on the table, store the center position of each register mark in the computer, remove the proof print, then place the test print on the table and check the position of each color register mark on the test print. The position of the center is determined, and the computer compares the positional relationship between the centers of the register marks with the positional relationship between the centers of the corresponding register marks stored in the computer to determine the deviation value. A registration method for an offset printing press, characterized in that a computer outputs a correction signal to a registration adjustment device of the printing press so as to correct the registration. 2. A machine base having a table for placing printed matter on its surface and having an image input camera installed above the table so as to be movable in the horizontal direction, a registration adjustment device for the printing machine, and a computer; The computer includes a storage unit that stores information on the center position of each color register mark on the proof print input from the camera, and compares the center position information of each color register mark on the test print input from the same camera with the stored information to determine the deviation thereof. a comparison calculation unit that outputs a value signal, and the register adjustment device inputs the deviation value signal to adjust the position of the plate cylinder. Device.