JP2812987B2 - Method and apparatus for detecting register amount in printing press - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a register amount detecting device for a printing press, and is particularly useful when applied to a register operation of each plate cylinder of a multicolor printing press.

<Prior Art> FIG. 3 is an explanatory view conceptually showing a six-color offset sheet-fed printing press. As shown in the figure, the printing press 010 includes a paper feeder 020 and six printing units 031,032,033,034,03.
5,036 and a paper discharging device 040 are provided. Each printing unit 03
Each of 1 to 036 has a plate cylinder _RH on which a printing plate is mounted, and a blanket cylinder _RG to which an image on the plate is transferred in contact with the plate cylinder _RH .
When, and a圧銅R _A applying printing pressure contact against the blanket cylinder R _G.

Paper 050 fed from the sheet feeding device 020 is transferred to the printing units 032 to 036 of adjacent the transfer cylinder R _W are printed by passing between the blanket cylinder R _G and the impression cylinder R _A. The paper 050 that has passed through the printing unit 036 of the last stage and has finished printing in six colors is transferred to the paper discharging device 040 and stacked.

In such a series of print steps, in each of the printing units 031 to 036, registration combined operations of each plate cylinder R _H of each printing unit and printed with a pattern example cruciform reference mark (register marks) on a sheet 050 031-036 To serve.

The registration operation according to the prior art using the reference mark has been performed in the following manner.

That is, a sheet 05 on which printing of six colors has been completed in a series of printing steps.
The operator enlarges and visually recognizes the fiducial marks overprinted with 0 with a loupe or the like, and visually detects the relative deviation amount of each fiducial mark, and then adjusts each plate cylinder until these deviations disappear. Such misregistration adjustment can be performed for each of the printing units 031 to 036 by manually or manually operating a register device attached to each of the printing units 031 to 036 using a remote control device. It is supposed to do it.
However, when the registration is made, the reference marks printed by the printing units 031 to 036 completely overlap.

<Problems to be Solved by the Invention> As described above, the registration in the prior art is based on the amount of deviation observed and observed by the operator on the fiducial mark of the test-printed paper 050, and the registration device is intuitively perceived by the operator. Since each plate cylinder _RH was adjusted by the operation, the amount of displacement could not be accurately detected, and a correction operation several times was performed by trial and error until the register was perfectly matched. For this reason, not only a great deal of time is required for the registering operation, but also test printing is performed for each correction, so that a large number of waste sheets are generated. Further, since the registering operation itself is a troublesome operation of visually observing a slight misregistration, there is also a problem that a great deal of fatigue of the operator is caused.

The present invention has been made in view of the above-described problems of the related art, and provides a method and apparatus for detecting a register amount in a printing press capable of automatically detecting a relative displacement amount of each plate cylinder of a printing press performing multicolor printing. With the goal.

<Means for Solving the Problems> The configuration of the present invention that achieves the above object has the following features.

(1) Each printing plate of a printing unit having a plurality of printing units, each having two vertical sides extending in a horizontal direction which is a direction in which paper is transferred in a printing press and a horizontal direction which is a direction perpendicular to the vertical direction. A register mark, which is a set of marks obtained by printing a mark formed by shifting the position on each printing plate relatively on one sheet of paper, is formed by imaging means to form video data representing the register mark. Then, based on the video data, the distance between the same two sides of the other mark with respect to the two sides extending in the vertical and horizontal directions of the reference mark is calculated, and the relative displacement between the respective printing plates is zero. By comparing the distance between the two sides of the other mark with respect to the two sides of the reference mark in the case and the calculation result, the relative shift amount between the respective printing plates in the horizontal direction and the vertical direction is calculated, and each shift amount is represented. Day Data, and based on the data representing the relative displacement amount of each printing unit and the current position data of the plate cylinder for each printing unit, both data are added for each printing unit, and the added data (S ₁ , S ₂ , ..., S _n ), and the largest one (S ₁ , S ₂ , ..., S _n ) of the added data (S ₁ , S ₂ , ..., S _n )
_max ) and the smallest one (S _min ) are extracted, and a center value S _mid is calculated by the following equation. Further, each addition data (S ₁ , S ₂ ,..., S _n ) and the center value S _mid are added, and the position of the plate cylinder is adjusted based on the data thus obtained.

(2) Each plate of a printing unit having a plurality of printing units, each having two vertical sides extending in a horizontal direction which is a direction in which paper is transported in the printing press and a horizontal direction which is a direction perpendicular to the vertical direction. A register mark, which is a set of marks obtained by printing a mark formed by shifting the position on each printing plate relatively on one sheet, and video data representing the register mark by imaging the register mark. Based on the imaging means to be formed and the video data, the distance between the same two sides of the other mark with respect to the two sides extending in the vertical and horizontal directions of the reference mark is calculated, and the relative displacement between the respective printing plates is calculated. By comparing the distance between the two sides of the other mark with respect to the two sides of the reference mark in the case of zero and the above calculation result, the relative shift amount between the respective printing plates in the horizontal direction and the vertical direction is calculated. A register shift amount calculating section for sending data representing the print position, and data indicating the relative shift amount for each print unit and the current position data of the plate cylinder for each print unit. Add and add data (S ₁ , S ₂ ,…, S
_n ), and the maximum (S _max ) and the minimum (S _min ) of the added data (S ₁ , S ₂ ,..., S _n ) are extracted, and the central value S is calculated by the following equation. calculate _mid , Further, a control unit that adds each of the addition data (S ₁ , S ₂ ,..., S _n ) and the center value S _mid and controls the register device based on the data thus obtained to adjust the position of the plate cylinder. And having

<Operation> According to the present invention having the above configuration, the relative displacement of each printing plate in the paper flow direction (the direction in which the paper is transported in the printing press; hereinafter, referred to as the top-to-bottom direction) and the left-right direction (the direction perpendicular to the top-to-bottom direction). The amount is the amount of deviation between the marks printed by each printing unit in the register mark printed on the paper on which a series of printing has been completed, that is, the left and right of the reference mark and the left and right of each other mark with respect to one side in the vertical direction, and It is visualized as the amount of displacement of one side in the vertical direction.

The image pickup means picks up the image of the register mark and sends the image data to the register shift amount calculating section. As a result, the register shift amount calculating section calculates the relative shift amount based on the video data of the register mark, and sends out data representing each shift amount.

<Embodiment> An embodiment of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is an explanatory diagram showing a register mark. As shown in the figure, this register mark 1 is a plurality of square marks (four in the present embodiment, which is a case of four-color printing).
It is printed as an aggregate of M ₁ , M ₂ , M ₃ , and M ₄ in the upper right margin of the printed paper.

Mark M ₁ ~M _4, for example FIG. 3 in the printing machine and the same type of offset four-color sheet-fed printing press showing like, multi-color printing press each one at successively printed in four printing units independent for each color Is done. That is, each printing plate of each printing unit is marked
Marks corresponding to M ₁ ~M ₄ is is formed. At this time, the marks formed on each printing plate are formed so that the positions on each printing plate are relatively shifted by a predetermined amount. As a result, in each printing unit, the printing plate, that is, the plate cylinder occupies the normal position. If it is, the relative positional relationship between the mark M ₁ ~M ₄ which are sequentially printed in each printing unit is always in a constant relationship (hereinafter, thus printing plate and plate cylinder and Uranaii the normal position in normal position that you are also referred to as the mark M ₁ ~M ₄ regular position mark M ₁ ~M ₄ in this case).

Mark M ₁ ~M H _{1 ~H 4} a side extending in the lateral direction of _4, if for these H ₁ to H ₄ one side extending perpendicular vertical direction is V ₁ ~V _4, sides H _1, V ₁ mark M ₂ ~M ₄ of the normal position in this embodiment relative to the have the relationship in the following table 1. Incidentally, in the table X the length of one side of the mark M ₁ ~M _4, alpha is the gap between the mark M ₁ ~M ₄ adjacent.

Therefore, the distance to the sides H _1, V ₁ of each side _{H 2, V 2 ~H 4,} V 4 (H
₁ −H ₂ , H ₁ −H ₃ , H ₁ −H ₄ , V ₁ −V ₂ , V ₁ −V ₃ , V ₁ −V ₄ )
Be calculated distance (hereinafter this is referred to as normal data) and the relative amount of displacement circumferential direction and lateral direction of the mark M ₂ ~M ₄ relative to the mark M ₁ by comparing between the sides in the normal position it can.

The shape of the mark M ₁ ~M ₄ has been a square, not limited to this shape. Each mark M ₁ ~M ₄ is not limited as long as having two sides orthogonal to each other extending in the circumferential direction and lateral direction. Further, since the embodiment is a case of four-color printing, but the mark M ₁ ~M ₄ was four forms, this number is similar to the foregoing embodiment in accordance with the number of number of colors, i.e. independent plate cylinder There is no argument that it should be increased or decreased in any way.

FIG. 2 is a block diagram showing a register amount detecting device according to an embodiment of the present invention together with a register device and a control unit of the register device.

As shown in the figure, the sheet 2 is intended to register mark 1 is a set of marks M ₁ ~M ₄ by a series of printing steps have been printed, after the printing register marks 1, the sample stage by the operator 3 It is placed on. The camera 4 serving as an image pickup means is provided with a sample angle 3 via a fixed angle 5 so as to image the register mark 1 of the sheet 2 from above.
, And transmits a video signal which is video data representing the registered register mark 1.

The misregistration amount calculation unit 6 receives the video signal and inputs distances (H ₁ −H ₂ , H ₁ −H ₃₎ of the other marks M _{2 to} M _{4 from} the sides H ₁ , V ₁ of the reference mark M _1. , H ₁ −H ₄ , V ₁ −V ₂ , V ₁ −V ₃ , and V ₁ −V ₄ ), and each of the marks M _{2 to} M is obtained by comparing each operation result with normal data. it is intended for calculating the relative amount of deviation ₄ of the mark M _1. More specifically, the register shift amount calculation unit 6 includes a binarization processing unit 6a, a system controller 6b, a CRT 6c, a CRT controller 6d, a program memory 6
e, video data memory 6f, communication interface 6g, I / O
It has a controller 6h, an operation panel 6i, and a printer 6j.

Among these, the binarization processing unit 6a binarizes the video signal sent from the camera 4 using the gradation value preset by the operation panel 6i via the I / O controller 6h as a threshold value, Create data. The system CPU 6b temporarily stores the plane binary data in the video data memory 6f, reads the plane binary data from the video data memory 6f, and displays the plane binary data on the CRT 6c via the CRT controller 6d, as described above. calculates a relative amount of deviation from the normal position of the circumferential direction and lateral direction of each mark M ₂ ~M ₄ marks M ₁ of the register mark 1 as a reference. The relative displacement calculated in this manner is displayed on the CRT 6c, is output to the printer 6j, and is sent to the control unit 7 via the communication interface 6g. Operation panel 6i correspondence relationships of the printing unit and the mark M ₁ ~M _4, together with the setting of various data, and for operating the start and stop or the like of a series of processes of misregistration amount calculation unit 6. The program memory 6e stores a processing procedure in the register shift amount calculating section 6.

The control unit 7 inputs data representing the relative shift amount calculated by the register shift amount calculating unit 6 and performs predetermined processing.
The position of each plate cylinder of each printing unit is adjusted via the register device 8 so that the relative displacement amount becomes zero. The control unit 7 of this embodiment uses a PQC (printing quality control) device. This PQC device has a dampening water controller 7h, a fountain controller 7j, an ink feed controller 7k, etc. in addition to the register controller 7i for directly controlling each register device 8, and is not directly related to registration. Wet water, fountain and ink feed, which have a significant effect on print quality, are each controlled. In FIG. 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 the data representing each printing unit via the communication interface 7b, converts the relative deviation amount into actual control data, and controls the register device 8 to thereby control each printing unit. The phase of each plate cylinder is adjusted (correction of a shift in the vertical direction), and the phase of each plate cylinder in the axial direction of the cylinder is adjusted (correction of a shift in the left-right direction).

The control unit 7 according to the present embodiment has data indicating where the adjustment position of each register device 8 is currently located, and compares the current position data with data representing the relative deviation amount to obtain the most promptly and for each plate. The main CPU 7a calculates the adjustment amount closest to the center of the torso cylinder, and controls each register device 8 through the register controller 7i.

That is, the relative shift amount of each printing unit is supplied to the controller 7 from the misregistration amount calculation unit 6 in D _1, D _2, D _3, D ₄ (subscript D is the number of the printing unit, the mark M ₁ ~ corresponds to M _4), also when detected by the position detector of each printing unit by the control unit 7 has the current position data of the cylinder of each printing unit and _{P 1, P 2, P 3} , P 4 First, data S ₁ (= D ₁ + P ₁ ), S ₂ (= D ₂ + P ₂ ),
Find S ₃ (= D ₃ + P ₃ ) and S ₄ (= D ₄ + P ₄ ).

Then extract the maximum value S _max and a minimum value S _min in the data S ₁ to S _4, it calculates a central value S _mid.

S _{1 to} S ₄ are added to S _mid to calculate SX ₁ , SX ₂ , SX ₃ , and SX ₄ .

SX ₁ = S ₁ + S _mid , SX ₂ = S ₂ + S _mid , SX ₃ = S ₃ + S _mid , SX ₄ = S ₄ + S _mid The calculations above are performed by the main CPU 7a, and these data S
The X ₁ ~SX ₄ sends to the register controller 7i. As a result,
Register controller 7i converts the data SX ₁ ~SX ₄ to the actual control data, for adjusting the position of each plate cylinder via a respective register device 8.

The operation of the present embodiment will be described together with a series of registration operations.

First inputs whether the mark M ₁ ~M ₄ by operating the operation panel 6i is printed by any printing unit in association. Next, a sample sheet 2 on which a register mark 1 as an aggregate of marks M _{1 to} M ₄ is printed is placed on a sample table 3.
The video signal representing the register mark 1 captured by the camera 4 from the sheet 2 in such a state is reproduced on the CRT 6c via the binarization processing unit 6a and the CRT controller 6d. The position of the paper 2 is adjusted so that the mark 1 occupies substantially the center of the screen of the CRT 6c.

After the position adjustment of the sheet 2 is completed, the following operation is executed by the register shift amount calculating section 6 by operating the "start" button on the operation panel 6i. That is, in response to a command from the system CPU 6b, the binarization processing unit 6a binarizes the video signal based on a threshold set in advance on the operation panel 6i, and forms plane binary data. The plane binarized data is temporarily stored in the video data memory 6f by the system CPU 6b and sent to the CRT 6c via the CRT controller 6d. As a result, the CRT
In step 6c, the binary data is displayed instead of the register mark 1. Next, the system CPU6b is based on planar binary data stored in the video data memory 6f, according to the algorithm described above based on Figure 1, top and bottom and the mark M ₂ ~M ₄ relative to the mark M ₁ Calculate the relative displacement in the left-right direction. Thereafter, the system CPU 6b issues a data communication request to the control device 7 via the communication interface 6g, and sends out the relative deviation amount and the data of the printing unit corresponding to the relative deviation amount.

The control unit 7, which has received the relative shift amount and the data of the printing unit corresponding thereto, operates the register device 8 to adjust the register shift of the plate cylinder between the printing units.

In the above embodiment, the data representing the relative displacement calculated and detected by the register displacement calculator 6 is stored in the controller 7.
And the register is automatically registered via the register device 8. However, based on the data indicating the relative shift amount detected by the register shift amount calculating section 6 and projected on the printer 6j, the operator can directly perform PQC. The registration may be performed remotely by operating a control device such as a device, or by the operator directly operating the registration device.

<Effects of the Invention> As described above in detail 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 has been conventionally performed visually, is automatically and absolutely determined. Since the data can be represented as simple data, the registration operation of the plate cylinder in the vertical and horizontal directions can be performed quickly and accurately.

[Brief description of the drawings]

FIG. 1 is an explanatory view for explaining a register mark and a principle of detecting a register shift amount using the register mark according to the embodiment of the present invention. FIG. 2 is a block diagram showing an embodiment of the present invention.
The figure is an explanatory view conceptually showing a six-color offset sheet-fed printing press. In the drawings, 1 is a register mark, 2 is a sheet, 4 is a camera, 6 is a register shift amount calculation unit, and M ₁ , M ₂ , M ₃ , and M ₄ are marks.

Claims (2)

(57) [Claims] 1. A printing unit having a plurality of printing units each having two vertical sides extending in a horizontal direction which is a direction in which paper is transported in a printing press and a horizontal direction which is a direction perpendicular to the vertical direction. Image data representing a register mark, which is a set of marks obtained by printing, on a single sheet, a mark formed on a printing plate by displacing the position of each printing plate relative to each other by an image pickup means. Then, based on the video data, the distance between the same two sides of the other mark with respect to the two sides extending in the vertical and horizontal directions of the reference mark is calculated, and the relative displacement between the respective printing plates is zero. By comparing the distance between the two sides of the other mark with respect to the two sides of the reference mark and the above calculation result, the relative shift amount between the respective printing plates in the horizontal direction and the vertical direction is calculated, and each shift amount is calculated. Represents It sends out the data, current position data and the added data by adding two data for each printing unit based on the (S ₁ of the plate cylinder for each data and each printing unit representing the relative shift amount of each printing unit, S ₂ ,..., S _n ), and the maximum (S _max ) and the minimum (S _min ) of the added data (S ₁ , S ₂ ,..., S _n ) are extracted. Calculate the center value S _mid by the formula, Further, each addition data (S ₁ , S ₂ ,..., S _n ) is added to the center value S _mid, and the position of the plate cylinder is adjusted based on the data thus obtained. A method for detecting the register amount in a printing press. 2. A printing unit having a plurality of printing units, each having two vertical sides extending in a vertical direction which is a direction in which a sheet is transported in a printing machine and a left and right direction which is a direction perpendicular to the vertical direction. A register mark, which is a set of marks obtained by printing on a single sheet a mark formed on a printing plate by displacing the position on each printing plate relatively, and an image representing the register mark by imaging the register mark Based on the imaging means for forming the data, and based on the video data, the distance between the same two sides of the other mark with respect to the two sides extending in the vertical and horizontal directions of the reference mark is calculated, and the relative displacement between the respective printing plates is calculated. When the amount is zero, the distance between the two sides of the other mark with respect to the two sides of the reference mark and the above calculation result are compared with each other to calculate the relative shift amount in the horizontal direction and the vertical direction between the printing plates, A register shift amount calculating unit for sending data indicating the shift amount, and a register shift amount calculating unit for each printing unit based on the data indicating the relative shift amount for each printing unit and the current position data of the plate cylinder for each printing unit. Add data and add data (S ₁ , S ₂ ,…,
S _n ), and the maximum (S _max ) and the minimum (S _min ) of the added data (S ₁ , S ₂ ,..., S _n ) are extracted,
Calculate the center value S _mid by the following formula, Further, a control unit that adds each of the addition data (S ₁ , S ₂ ,..., S _n ) and the center value S _mid and controls the register device based on the data thus obtained to adjust the position of the plate cylinder. And a register amount detecting device for a printing press.