KR20060116374A - The automatic control method of register controller of prints equipment - Google Patents

Abstract

A method for controlling register error of multicolor gravure printing using scanning head and CCD camera is provided to find and correct register errors automatically, to detect the errors of light color printing in pixel units through CCD camera, to allow precise printing of multicolor and various patterns through the known method using scanning head, and to allow examining printing quality during printing process. The method for controlling register error of multicolor gravure printing on opaque film or aluminum foil includes: setting rotation roll(printing roll) of printer(job preset step); starting printing process; setting a standard value of register mark in a main control device(10); printing the first color by number 1 printing unit; detecting errors against the standard value of register mark by scanning head and/or CCD camera; correcting the detected errors by controlling motor through main control device; printing the second color by number 2 printing unit; repeating steps of detecting and correcting errors for necessary number of colors; and completing printing process.

Description

The automatic control method of register controller of prints equipment

1 is an exemplary view for explaining a method of measuring a register error through a conventional registration,

2 is an exemplary view for explaining a method of measuring a register error using a conventional register mark;

3 is a view schematically showing an apparatus for detecting an error using a scanning head of a conventional register mark;

4 is a flowchart illustrating an error control method of sequentially performing printing by reducing an error of printing using a register mark in the present invention;

5 is a flowchart showing a procedure for determining a reference value which is a standard of a register mark in the present invention;

6 is a flowchart showing a procedure of detecting an error caused by a CCD in the present invention;

7 is a flowchart illustrating a procedure of detecting an error caused by the scanning head in the present invention.

<Brief description of the major symbols in the drawing shown>

10; Specifying Reference Values for Register Marks

20; Detecting the error by CCD

30; Detecting errors caused by the scanning head

The present invention relates to a method for automatically controlling the register error of printed matters, and in particular, by detecting the error of a register generated in the process of printing a pattern on a printing film by painting a color and color performed in a multicolor gravure printing process. A method of controlling a register error of multi-color gravure printing that can be corrected by using a CCD camera or a scanning head and a CCD camera and a scanning head simultaneously to automatically detect and correct a register error of a printed material. will be.

In general, when printing a variety of patterns, symbols, characters, etc. on the tubular film used for various printed materials, such as confectionery bags and wrapping paper, a variety of colors through the gravure printing process.

However, even if the film fabric supplied to the printing apparatus is normally supplied in the printing process, the position of the film fabric is separated from the set position in the printing process, thereby causing a problem in that print quality is deteriorated.

That is, in the case of printing 8 degrees on the film fabric while the film fabric of one roller is supplied for the gravure printing process, one unit (printer) per 1 degree is required so that 8 units operate.

At this time, the film fabric supplied to each unit for printing is printed in the color set in the unit.

Therefore, the film fabric automatically supplied to each unit must be exactly matched to the set position to complete printing of 8 degree color normally in each unit.

By the way, the material of the film fabric supplied and printed in the printing process is a kind of synthetic resin, mainly made of soft PVC, PP, and PE, and may be caused by stress or the like applied from the supply roller in the process of supplying each unit. The film fabric is partially stretched, resulting in a register error.

That is, since a plurality of guide rolls and dryers pass through, shrinkage and expansion of the printed matter occur, and a slight change in the length of the printed matter occurs due to slips generated in the guide roll and the pressure and the tension change between each plate.

However, if these small changes are constant and driven by the same prime mover and the copper plates operate in perfect synchronization, the error of the register is not a problem, but if the length of the printed material changes until reaching the unit after printing in one unit, Since an error occurs, the error of the register must be detected and corrected.

Many methods of correcting the error of the register have been developed, one of which is a method of detecting and correcting the error using the registration shown in FIG.

That is, referring to FIG. 1, when a user wants to detect a register error, a register mark called normal registration (1) (2), which is difficult to visually identify, is put in each color and compared with each other. Review and identify the error.

The dome beam 1 is a dome beam shown at 1 degree in the printing process, and the dome beam 2 is determined as a dome beam shown at 2 degrees. When the dome beam 1 and the dome 2 are fitted together, printing is performed. It should be regarded as a perfect match.

In other words, when the dome and the dome match, the printed cookies bags are printed without being twisted, and thus, the patterns of figures or pictures to be printed may be regarded as accurately printed without overlapping each other.

Of course, as shown in FIG. 1, if the dome 1 and the dome 2 do not coincide with each other, an error occurs.

In other words, the amount of error in the horizontal line is the error amount in the longitudinal direction, and the amount of error in the vertical line is the error amount in the horizontal direction.

When such a register error occurs, the user corrects the amount of error immediately generated.

In order to correct such a register error, the user makes a correction while looking at the pulse displayed on the oscilloscope. Since the pulse displayed on the oscilloscope is displayed while moving continuously, it is difficult to set the gate address of the system while viewing the continuously moving pulse.

In addition, when operating a small number of units based on the unit in a limited space to block the front of the empty unit, if more than eight units need to add a main body, there is a problem that the unit is difficult to add or subtract.

In addition, when correcting a resistor error while looking at the pulse displayed on the oscilloscope, the electrical contact of the switches causes contact failure due to contamination of dust, etc., resulting in inconvenient operation of the system. .

Therefore, a method developed to solve this problem is to read a register mark that is printed in the same color as the pattern or figure to be printed on one end of a cookie bag, etc., and compare it with a reference value.

In other words, as shown in Figs. 2 and 3, the register marks 5 are arranged in the longitudinal direction so as to be 1 degree, 2 degrees in the vertical direction with respect to the advancing direction of the printed matter (fabric). The n mark register marks 5 are printed at 20 mm intervals.

At this time, when the register mark 5 is regarded as no error when there is a 20 mm gap, if the gap of the register mark 5 changes to 19.5 mm or 20.5 mm, it is detected that a register error of ± 0.5 mm has occurred.

In addition, if an error occurs to the left or right from the vertical line of the register mark 5 printed in the left and right direction, the interval between the inclined portions of the register mark is changed, so that this change is detected and becomes a register error in the left and right direction.

The scanning head and the pulse generator are responsible for detecting the register error from the register mark 5.

3 is a diagram schematically illustrating an apparatus for detecting an error of the register.

That is, referring to FIG. 3, the scanning head S / H performs a function of detecting a register mark, and is installed near the bottom of the dryer so as to be detected immediately after printing of each unit.

Only one pulse generator (P / G) is installed in one printing press, and performs a function of distinguishing a printed register mark from another printing, and the scanning head (S / H) and the pulse generator (P / G) In combination, the register error is detected and only the register mark is applied to the central control control 10.

The scanning head S / H includes two lenses and a photodiode (not shown) with respect to one light source lamp (not shown), and a reflecting plate installed at a position opposite to the scanning head S / H. R / P) to focus and receive it on each of the two photodiodes.

When each register mark 5 passes through the two focal planes, a change of light appears in each photodiode, and the change of light is converted into a current pulse and applied to the controller 11.

When the current pulse is generated in two photodiodes at the same time, the resistor error in the up-down direction and the left-right direction becomes zero.

On the contrary, when there is a time difference between the up edges of the current pulses, an error in the up and down directions occurs. When a time difference occurs in the down edges, a resistor error occurs in the left and right directions.

Therefore, the error between the register marks 5 is measured in this way, and accordingly, the error is adjusted by rotating a motor capable of interlocking the rotary rolls from side to side.

By the way, many problems have been derived.

That is, in the case of gravure printing, printing is performed on paper such as a bag of confectionery, opaque film, aluminum foil, and the like. In the case of light colors (eg yellow), the scanning head has its register mark 5 due to diffused reflection of light. It is difficult to detect errors because of errors.

In addition, if the color to be printed is the same color as the light source lamp bladder in the scanning head, or if the color is similar to the detection ability is poor.

In addition, when the application amount of the ink spreads around the register mark 5, there is a problem that it is difficult to measure the distance of the printing focus.

These problems, of course, result in a problem that the printed pattern is actually distorted and overlaps with each other, resulting in deterioration of the quality of the product.

The present invention, which solves the above problems, by correcting the error by automatically detecting the error of the register generated in the process of printing a pattern on the printing film by painting the color and color carried out in the multi-color gravure printing process, the means By using a CCD camera or a scanning head and a CCD camera and a scanning head at the same time to provide a method for controlling the register error of the multi-color gravure printing to achieve a more accurate printing by automatically detecting and correcting the register error of the printed material.

In addition, the present invention is the JOB PRESET step of setting the rotary roll (print roll, etc.) of the printing press, the step of starting printing by starting the printing press, the step of specifying the reference value of the register mark in the central control unit, the first printing unit Printing the first color by detecting the error, and detecting an error of a reference value through the CCD camera or the scanning head, or the CCD camera and the scanning head in detecting the error of the first register mark; Adjusting the motor through the device to correct the error, printing the second color by the second printing unit, detecting the error according to the fourth step, and correcting the error according to the fifth step. It is composed of the steps of performing the required number of colors and the steps of completing the printing to make clearer printing on the surface of opaque film, aluminum foil, etc. To provide a register error control method.

The present invention also provides a method of designating a reference value of the register mark of the second step, wherein the CCD camera recognizes the first register mark in units of pixels during the first printing. Storing the X and Y axis positions of the register mark recognized in units in the central control unit; recognizing the register mark in pixels on a second basis when the second register mark is printed secondly; Determining whether there is an error between the second register marks, adjusting the error if there is an error, specifying the state as a reference value if there is an error, determining whether there is the error by the number of chromaticities required, and a reference value. The register of multicolor gravure printing consisting of the steps of setting the reference value by repeating the step of specifying To provide a control method for error.

In addition, the present invention is a step of detecting an error with respect to the reference value by the CCD camera of the fourth step, the step of reading the X, Y axis position of the register mark in the pixel unit at printing, and comparing with the specified reference value of the register mark, By comparison, if there is an error, the motor is controlled to adjust the error to start the next printing, and if there is no error, the present invention is to provide a register error control method of multicolor gravure printing.

The present invention is similar to the conventional printing method in that it is a register error control method of multicolor gravure printing for printing on the surface of an opaque film, aluminum foil, or the like.

However, the present invention has a CCD camera on each printing roll and inspects and controls the register mark pixels of the image taken by the camera, so that the scanning head can accurately measure colors that are difficult to read. It will be described in detail in conjunction with the drawings shown because there is a great feature that can be controlled more precise printing, thereby resulting in a significant improvement in the quality level of the printed matter to be printed.

As shown in Figure 4, the present invention begins with a JOB PRESET step of setting a rotating roll (print roll, etc.) of the printer, as shown in the flow chart of FIG.

That is, structural setting of the initial printing units is performed to start printing.

There are many types of prints for gravure printing, so if you want to print one bag (example) and print the next bag, you have to set the structural printing rolls and rolling rolls.

The reason is that the size of the cookie bag cannot all be the same, and the pattern of the pattern is different.

Therefore, printing a small cookie bag and then sticking to the position of the rotary roll and the printing roll arranged for the cookie bag and printing a large cookie bag has a large error range.

This error range is so large that it is likely to deviate from the correction limit of the error through the CCD camera and the scanning head to be described later.

Eventually, this JOB PRESET step is set by moving the rotating roll and the printing roll up and down through the motor so that an error can be generated within the error measuring range of the register mark where the CCD camera and the scanning head, which will be described later, can measure the error. To do.

Next, the second step: start the printing machine to start printing.

In other words, the film in the state that the confectionery bag, etc., which is required to be printed, is passed through the inside of the printing machine, and printing is started.

However, if the basic principle of printing is explained here, only one color is printed in one printing unit.

Therefore, if a multi-colored color exists in printed matter such as a bag of cookies, the printing unit is set according to the number of colors and each printing unit prints only the color that is correct.

Therefore, in the state in which all the colors are printed, one pattern shape and the background are combined and printed.

Next, a third step: a step 10 of designating a reference value of the register mark 5 in the central controller.

In other words, in this step, a reference value, which is a reference mark of a register mark, is designated so that a shape such as a pattern or a shape printed on a cookie bag can be printed well.

If the pattern or shape to be printed is printed on one printing unit, one color is painted, which simultaneously prints a register mark on the end of the film.

Later, in the next print job, another color is printed on another printing unit, wherein the printing is performed on the film by judging whether it is correctly printed perpendicularly to the distance difference between the first printed register mark and the immediately following register mark. Judgment is made by judging whether the shape of the pattern or the like is well printed.

Here, the reference value is the X and Y axis coordinates of the register mark, which is the reference for this determination.

However, the present invention may alternately use a method of determining a reference value through a CCD and a method of setting a reference value through a scanning head in determining the reference value, or both.

Here, first, the method of specifying the reference value of the register mark through the CCD camera will be described.

That is, as shown in FIG. 5, the CCD camera recognizes the first register mark printed at the same time in pixels by printing a pattern such as a pattern through the first color.

That is, it recognizes the coordinates of the X and Y axes, which are the phases of the first register mark printed past the first printing unit.

Of course, in order for the CCD camera to recognize the coordinates of the X and Y axes, the camera is moved through the traverse to the proper position of each printing unit, and the focus, brightness and zoom of the CCD camera are adjusted. Should be taken in one condition.

Next, the X and Y axis positions (reference values) of the register mark recognized in pixel units are stored in the central controller.

The position (reference value) of this register mark is stored in the central control unit because it is to be compared with the phase (position) of the register mark to be printed later.

Next, when the second register mark is printed second, the register mark is recognized by a separate CCD camera in pixel units.

That is, the second register mark printed together when the second color immediately after printing the first color is also recognized by a separate CCD camera attached to the printing unit in pixel units.

Therefore, thereafter, a step of determining whether there is an error between the first and second register marks is performed.

In addition, through the above steps, if there is an error, the error is adjusted, and if there is no error, the state is designated as a reference value.

Thereafter, the step of determining whether there is an error by the number of chromaticities (colors) required to be printed and the step of specifying the reference value are repeated, and the reference value of each printing unit is determined.

The important thing here is that the register mark is printed by the number of colors. The first register mark (the phase is compared with the reference value) is the second printed register mark, and the second register mark (the phase is the reference value) is compared. The register mark to be printed is the third printed register mark.

Of course, the register marks to be printed later become the reference value compared to the previous register mark (the phase is the reference value).

The question mark (?) Shown in FIG. 5 is displayed in determining the reference value because the shape of the printed pattern or the shape of the printed matter may vary depending on several index printed matter.

And when the reference value is determined, all of them are stored and used in the central control unit.

That is, for example, about 100 sheets of films, such as a confectionery bag having the same pattern, are printed to print 100 sheets, for example, the reference values inputted to the central control unit.

In addition, for another cookie bag to be printed in the form of a different pattern, such as is stored in the central control unit through the steps of specifying the above-mentioned reference value, the error is detected by using the reference value.

And the method of determining the error detection reference value through the latter scanning head is a known state as described in the prior art.

In brief, the reference mark is also determined by reading a register mark printed on one end of a film or the like through scanning and comparing the read phase with that of a previously printed register mark.

In the present invention, the fourth step is to print the first color by the first printing unit.

That is, the first color to be printed is printed on the film with a register mark, and the actual printed matter (product) is printed.

Of course, the first color printing by the printing unit No. 1 of the fourth step will be a register mark having the same color as that of the first printed pattern after the reference value is determined.

Thereafter, the fifth step: detecting an error of the first register mark is performed by detecting an error with respect to a reference value through the CCD camera or the scanning head or the CCD camera and the scanning head.

That is, in the present invention, in detecting the error of the register mark, the error may be detected only through the CCD camera mounted in each of the above-described printing units, and only by using the scanning heads mounted in each of the two printing units. May be detected, and an error with respect to the reference value may be detected by using the set CCD camera and the scanning head at the same time.

This situation is necessary because each error measuring device has advantages and disadvantages. In the case of the scanning head, as described in the related art, it is possible to print on paper such as a printed bag, opaque film, aluminum foil, or the like. In the case of light colors (e.g. yellow), it is difficult for the scanning head to read the register mark due to the diffuse reflection of light, making it difficult to detect an error (error).

Therefore, in this case, that is, if the color to be printed is a light color (yellow, etc.), an error may be detected 20 by a pixel through a CCD camera, and in other cases, the error may be detected 30 through a scanning head.

In any case, if some of the printing units of the present invention detect an error with respect to the reference value by the CCD camera, the order is as follows.

That is, as shown in FIG. 6, the register mark is read at the X and Y axis positions in pixels, and compared with the phase of the previous stage register mark, that is, the input (stored) reference value.

If there is an error in comparison, the motor is controlled to adjust the error to start the next printing, and if there is no error, the printing is started and the error is detected and controlled.

In addition, in some printing units of the present invention, if the error of the reference value through the scanning head 30 is detected, the order is as follows.

That is, as shown in Fig. 7, the register mark is read by the scanning head during printing, and a step of comparing the pulse difference with a specified reference value of the register mark is performed.

In the comparison, if there is an error, the motor is adjusted to adjust the error to start the next printing, and if there is no error, the printing is started and the error is detected and controlled.

For reference, the biggest difference between the method of detecting an error through the scanning head and the method of detecting an error through the CCD camera is related to time in the case of the scanning head, and the error measured by the CCD camera is related to time. Irrespective of the data displayed on the screen, the position of the data measured by the CCD becomes an accurate error detection unit.

Finally, a method of detecting an error with respect to the reference value by combining both the CCD camera and the scanning head is as follows.

That is, in a printing unit that prints a normal (not light) color, an error is detected by reading a register mark at the time of printing with a scanning head and comparing the pulse difference with a specified reference value of the register mark.

The CCD camera attached to the printing unit moves through the traverse to photograph the printed pattern and shape, not the register mark.

Therefore, while using a conventionally known method of correcting the specified reference value of the register mark and the pulse difference by reading with the scanning head, the pattern such as a pattern photographed by the CCD camera can be visually observed by the printer through the monitor under the control of the central controller. It could be.

Obviously, even through such visual observation, if the form of the color or pattern is printed well, it will produce a higher quality print.

If the error is detected and the register error control method shown in FIG. 4 is continued, the sixth step: if an error is detected, the motor is adjusted through the central controller to correct the error.

If the continuous printing is performed without correction in the state where the error is detected, the printing will be printed in a more distorted and overlapping state due to the stress caused by the open and rotating roll generated in the printing press.

Therefore, since the error of the reference value was detected through the CCD camera or the scanning head and the CCD camera and the scanning head, the detected central controller transfers the rotating roll precisely to the left and right by winding the motor by adjusting the motor. It is to adjust the angle and position of the rotating film.

Therefore, this angle and position are adjusted to the same value as the reference value to control the error.

Next, the seventh step: printing the second color by the second printing unit.

In addition, the eighth step: through the above-described methods, i.e., detecting the error according to the fifth step and correcting the error according to the sixth step is repeatedly performed as many times as necessary.

Thereafter, the ninth step is to complete the printing, and the method of controlling the register error of the multi-color gravure printing of the present invention ends.

As described above, the present invention can detect the error on a pixel-by-pixel basis through the CCD camera, thereby effectively controlling the error that may occur when printing light colors.

In addition, the present invention can detect the printing error through a well-known scanning head as well as a CCD camera, it is possible to print a pattern such as a pattern shape having a variety of colors without error, the color and printing of the printed matter printed through the camera during printing It is a useful invention that can examine the precision of the.

In addition, the present invention can control the error according to the register error control method of the multi-color gravure printing, and the printed confectionery bag is an excellent invention that can save the dignity of the product to be manufactured with excellent printing quality.

Claims (5)

Register error control method of multicolor gravure printing in the following order for printing on the surface of opaque film, aluminum foil, etc. First step: JOB PRESET step to set the rotary roll (print roll, etc.) of the printing press Step 2: start printing by starting press Step 3: Assigning a Reference Value of the Register Mark to the Central Controller (10) Step 4: printing the first color by the first print unit Step 5: detecting an error of a reference value through the CCD camera or the scanning head or the CCD camera and the scanning head in detecting the error of the first register mark. Step 6: If errors are detected, correct the errors by adjusting the motor through the central controller. Step 7: printing the second color by the second printing unit Eighth step: detecting an error according to the fourth step and correcting the error according to the fifth step as many times as necessary Step 9: finish printing The method of claim 1, The method of designating the reference value of the register mark of the third step, Specifying the reference value of the register mark through the CCD camera and recognizing, by the CCD camera, the first register mark in pixels for the first printing; Storing the X and Y axis positions of the register mark recognized in pixel units in a central controller; Recognizing the register mark in pixel units when the second register mark is printed secondly; Determining whether there is an error between the first and second register marks; If there is an error, adjust the error, and if there is no error, specify the state as a reference value A method for controlling the register error of multicolor gravure printing, comprising the steps of determining whether there is an error by the number of chromaticities to be printed and setting the reference value by repeating the step of specifying the reference value. The method of claim 1, Detecting the error with respect to the reference value by the CCD camera of the fifth step (20), Reading the register marks in pixel units on the X, Y axis position, and comparing them with the specified reference value of the register mark; In comparison, if there is an error, by adjusting the motor to adjust the error to start the next printing, if there is no error, the printing method of the register error control method of multi-color gravure printing, characterized in that consisting of steps. The method of claim 1, Detecting an error with respect to a reference value through the scanning head of the fifth step (30), Reading the register mark with the scanning head when printing and comparing the difference between the specified reference value of the register mark and its pulse; In the comparison, if there is an error, by adjusting the motor to adjust the error to start the next printing, if there is no error, the printing method of the register error control method of the multi-color gravure printing, characterized in that consisting of steps. The method of claim 1, Detecting the error of the reference value through the CCD camera and the scanning head of the fifth step, Reading the register mark with the scanning head during printing and comparing the difference between the specified reference value of the register mark and its pulse, the CCD camera photographing a printed pattern that is not a register mark; Multi-color gravure, comprising the steps of reading by the scanning head to correct the specified reference value of the register mark and the pulse difference, and visually observe the pattern shot by the CCD camera on the monitor under the control of the central control unit. How to control register error in printing.

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