JP2609421B2 - Automatic mold matching method and apparatus in automatic screen printing machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for automatic adjustment of pattern matching in multicolor printing of an automatic screen printing machine.
According to this, the mold matching is automatically adjusted with high precision.

[0002]

2. Description of the Related Art In a conventional automatic screen printing machine, the operator adjusts the pattern by manual operation for each screen according to the state while monitoring the state of the pattern after printing. It is carried out. The pattern matching operation must be performed in the repeat direction (the direction in which the cloth to be printed advances), at right angles to the direction, and in the direction of rotation. As multicolor printing requires more time and skill, the productivity and quality are improved. It is hindering.

[0003] For these reasons, the present inventor has filed Japanese Patent Application No.
No. 38784, a matching adjustment device is provided, and simple and reliable matching adjustment is performed by operating a monitor television and a switch. However, in the present invention, further, from the monitoring of the matching state to the adjustment of the matching. It measures automation.

[0004]

That is, an object of the present invention is to completely automate the adjustment of pattern matching in multicolor printing of an automatic screen printing machine, and to detect the pattern condition during printing by image processing. The present invention provides a method and an apparatus for automatically and accurately adjusting a mold according to the following.

[0005]

According to the present invention, prior to the printing operation, the same number of register marks as the predetermined number of colors of the printing pattern are printed on the cloth to be printed via the mother screen, and the printing is performed. A preparatory step of taking the registered register mark as basic image data into the image processing apparatus and storing the same, and performing printing using a pattern screen on which the register mark is made in the same position as the register mark on the mother screen, and printing each screen. Each register mark is taken into the image processing device as image data, the displacement value of the position between this image data and the stored basic image data is detected as the number of dots, and the number of dots of the above displacement value is converted into an actual adjustment amount. This is output to a screen adjustment mechanism provided for each printing unit, and the printing process for adjusting the pattern matching is performed. Die matching method in an automatic screen printing machine is provided, characterized in that.

According to the present invention, the same number of register marks as the predetermined number of colors are printed on both sides in the width direction in correspondence with each color of the printed pattern. A mother screen for pre-printing only a few minutes of register marks; a main pattern printing screen in which each register mark is made in the same position as a predetermined color register mark of the mother screen; provided behind the printing area; A plurality of CCD cameras that take in printed register marks as images; register cameras preliminarily printed on the mother screen are stored as image basic data, and are printed on the main pattern screen for printing.
Position of the image data of the workpiece and the stored basic image data
Displaces the respective printing units in accordance with and the number of the pulse; computer into a number of pulses striking the actual screen adjustment amount to the number of dots of the displacement value; detecting the displacement value as the number of dots, the image processing apparatus for outputting A mold matching device for an automatic screen printing machine, comprising a screen adjusting mechanism for adjusting the mold matching is provided.

[0007]

The pattern printing method of the present invention is roughly divided into a preparation process for capturing and storing basic image data and a main process for capturing and printing actual image data, and comparing these data with each other. Is performed by image processing, that is, digital image processing.

First, in a preparatory step, the same number of register marks as a predetermined number of colors of a printed pattern are printed on a cloth to be printed through a mother screen, and the printed register marks are used as basic image data in an image processing apparatus. Capture and store.

In this preparation step, not only can basic image data with high accuracy be obtained, but also this image data does not change regardless of the frequency of use or aging.
As long as the same screen is used, this is constantly referred to and provides excellent comparative base data.

[0010] In the pattern printing step, printing is performed using a design screen in which register marks are made at the same positions as the register marks on the mother screen. This makes it possible to compare the basic image data with the image data actually printed at the time of the register mark.

For this comparison, register marks for each screen after printing are taken into an image processing apparatus as image data. Next, the displacement value of the position between the image data and the stored image basic data is detected as the number of dots,
Output this.

The number of dots of the displacement value is converted into an actual adjustment amount of the screen, and this is output to a screen adjustment mechanism provided for each printing unit to perform a type adjustment.

According to the present invention, by combining the above-mentioned preparation step and the pattern printing step through image processing, both the detection of the state of the pattern matching and the adjustment of the pattern matching can be performed automatically without any human intervention. Doing so can save labor and increase productivity.

The detection of the matching state by image processing is extremely accurate compared to the naked eye, and has no effect of fatigue like the naked eye. Gives the advantage of gaining.

In general, image processing requires an extremely large-capacity storage device and a high-speed arithmetic device, but it is difficult.
In the present invention, since this processing is limited to a register mark having a very small area, there is an advantage that the matching state can be quickly detected even with a small-capacity storage device and a relatively low-speed arithmetic device.

In the present invention, corresponding to each color of the printed pattern,
The same number of register marks as the predetermined number of colors are engraved on both sides in the width direction, and the mother screen for pre-printing only the register marks of the predetermined number of colors on the cloth to be printed prior to the printing operation; Is used as a set, with a register mark of a predetermined color and a pattern printing screen having respective register marks made in the same position.

The image data is preferably taken in through a plurality of CCD cameras provided behind the printing area and taking in the printed register marks as images.

The image processing apparatus stores the register mark preliminarily printed on the mother screen as basic image data, and stores the stored basic image data and the pattern matching print.
Position of register mark printed in process with image data
The displacement value of the displacement is detected as the number of dots, and based on the detected value, the computer converts the number of dots of the displacement value into the number of pulses corresponding to an actual screen adjustment amount, and according to the number of pulses, An adjusting mechanism displaces each printing unit and performs a matching adjustment.

In the apparatus according to the present invention, there is obtained an advantage that the above-mentioned respective mechanisms are organically related to enable automatic mold matching during the printing process without any loss time.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The automatic pattern matching method of the present invention uses (1) a mother screen in which only register marks of the same number as a predetermined number of colors are made on both sides in the width direction for each printed pattern prior to the printing operation. Then, only the register marks for a predetermined number of colors are printed on the cloth to be printed. (2) The printed register marks are detected by two CCD cameras provided behind the printing area, and the positions thereof are measured and measured. Confirm the position data and store it in the image processing device as basic data, and store it. (3) In the printing operation, the register marks on the mother screen should be accurately printed at the same positions. (4) The CCD camera detects the register mark position of each screen after printing, and the mother data, which is the basic data described above. Detects the displacement value from the position of the clean register mark as the number of dots, outputs it to the matching control panel, and instructs it. (5) The computer in the matching control panel converts the number of dots of the displacement value into an actual adjustment amount. And
This is output to a screen adjustment mechanism provided for each printing unit to perform pattern adjustment.

Thus, the operator does not need to be involved in the mold adjusting operation, and the automatic mold adjusting operation is always performed with high accuracy in a short time.

FIG. 1 shows a schematic plane and an outline of control of an automatic screen printing machine using the automatic mold matching method according to the present invention.

A front roller 2 and a rear roller 3 are provided on the front and rear portions of the machine base 1, and an endless belt 4 is stretched around the front roller 2 and the rear roller 3.
It is intermittently driven every time.

On the surface of the endless belt 4, a cloth 5 to be printed is provided.
Is attached, and multicolor printing is performed via the screen 7 by the plurality of printing units 6-1 to 6-5. In this embodiment, the number of printings is five in each of the following description and each drawing, but the number is not limited to this.

Behind the final printing unit 6-5, two CCD cameras 10A and 10B are provided on both sides in the width direction of the cloth 5 to be printed, at positions where the register marks on both sides can be detected. Through the image processing device 11 and the matching control panel 13, automatic matching adjustment is performed as described above and in detail later.

FIG. 2 shows details of the screen 7 used in the present invention.

Normally, the screen 7 is provided with a pattern 7D, but in the present invention, in addition to the normal screen, there is no pattern 7D as described above, and the same number of register marks 7A and 7B as the predetermined number of colors are provided. A mother screen 7M on which only 7B is made is used.

The mother screen 7M has the same number as the number of prints.
Number register mark pairs 7A 1-5 and 7B 1-5
Only is defined from one side ee of the outer dimension of the screen frame 7F
Separated by dimensions a and b, at equal intervals d, and on another side f
Specified dimension l from -f_TwoAnd l ₁ Plate is in the position of
You.

The register marks 7A and 7B are both C
Although double circles are used in the embodiment to facilitate measurement and detection by the CD cameras 10A and 10B, single circles or other shapes may be used.

The normal printing screen 7 has a repeat length R from one side ee of the screen frame 7F with a prescribed dimension r of the same color for all colors, and a prescribed dimension w ₂ from the other side ff. design 7D to w ₁ at a is the plate-making.
Further, W including the register marks 7A and 7B is the printing width.

On each screen 7 for printing, register marks 7A and 7B are made in the same position as that of the mother screen 7M at the same time as the pattern 7D. In this case, the register marks 7A and 7B are used in order to confirm the displacement value with respect to the mother screen 7M by the CCD cameras 10A and 10B described later and to determine any one of the printing units 6-1 to 6-5. It is assumed that there is only one out of ５5.

Therefore, each of the five register marks 7A,
7B, the entire plate is prepressed on each screen 7, and the required No. 7B is used. May be masked with an adhesive tape or the like except for one of each. Only plate making may be performed.

In the present invention, printing is performed using the screen 7 described above. Prior to the printing operation, the register mark 7A is printed on the cloth 5 to be printed using only the mother screen 7M, for example, using the printing unit 6-5. And only 7B are printed. The printed register marks are sent intermittently to the measurement positions of the rear CCD cameras 10A and 10B.

FIG. 3 shows an image detection state of the CCD cameras 10A and 10B. The CCD cameras 10A and 10B are registered marks 7 printed on a mother screen 7M.
A and 7B are fixed and installed at positions within the field of view of the camera, and the position of the register marks 7A and 7B is measured as described below.

In the embodiment, as shown in FIG. 3, the CCD cameras 10A and 10B have a total field of view of 512 in both the X and Y directions.
It has a resolution of 0 dot / 1 dot = 0.02 mm. Therefore, the total field of view of the camera is 5120 × 0.02 = 1.
The size is 22.4 mm square.

In this field of view, the register mark 7
Reference line x in CCD camera for position measurement of A, 7B
a, xb and ya, yb are set, and this range is set to 5000 dots. That is, the range surrounded by the reference line is 500
0 × 0.02 = 100 mm square.

Register mark 7 printed on cloth to be printed
Each of the positions 1 to 5 of A is α from the reference line ya.₁ ~ Α_Five 
7B, the positions 1 to 5 are β from the reference line yb.₁ 
~ Β _Five And xb from γ₁ ~ Γ_Five It is measured as this
Each value is sent to the image processing device 11 as the number of dots,
Stored as basic data for each register mark position
You.

The installation position of the CCD cameras 10A and 10B does not require strict positional accuracy, and may be a position where each register mark substantially enters the center of the reference line range of the camera. Thus even above measured value alpha ₁ to? ₅ and β ₁ ~β ₅ is not central well, and gamma ₁ to? ₅ is the reference line ranges not be the same value. Since the distance l1 between the register marks 7A and 7B is a fixed value, one CCD camera 10
Γ _{1 to} γ ₅ may be measured only with B.

With the completion of the confirmation of the basic data of each position of the register mark printed on the mother screen 7M as described above, the printing operation on the normal screen 7 is started.

In printing, one of the register marks 7A and 7B is simultaneously printed along with the pattern 7D in accordance with the printing order. In the embodiment, the printing unit 6-1 has No. 6-
In No. 2, No. 2 and 6-5. 5 register marks are printed

The cloth to be printed 5 on which the corresponding register mark is printed together with the pattern is sequentially sent backward by intermittent feeding, and is temporarily stopped by the CCD cameras 10A and 10B.
The position of each printed register mark is measured.
This is compared with the basic data of the register mark position by the mother screen 7M, and the displacement is output as the number of dots.

FIG. 4 shows this state. The register marks 7A-1 and 7B-1 are those of the basic data by the mother screen 7M.
Is, for example, No. printed by the printing unit 6-1. One screen is shown. In FIG. 4, a positional error of .alpha.x on the 7A side in the X direction, .beta.x on the 7B side, and a .gamma.x in the Y direction are seen.

The printing units 6-1 to 6 are prepared by the above method.
The register mark positions of all the screens -5 are measured and detected every time the intermittent feed is stopped, and the displacement value compared with the basic data input to the image processing apparatus 11 is represented by the number of dots and the type matching control panel. 13 is output. Further, the state of displacement of each screen is selectively displayed on the monitor color television 12.

The displacement value αx or βx in FIG. 4 is an error in the X direction, that is, a repeat direction, γx is an error in the Y direction, and αx ± βx is detected as an error in the rotation direction θ. Then, the number of dots is converted into an actual adjustment amount and adjusted by a screen adjustment mechanism described later.

The measurement and comparison of the register mark of each screen described above may be performed every time the intermittent feed is stopped. In a state where the pattern matching is stable, the register mark is measured at an arbitrary number of feeds and at regular intervals. Is also good. These operations can be arbitrarily set in the image processing apparatus 11 in cooperation with the printing press control panel 14.

FIG. 5 shows the entire plane of the printing units 6-1 to 6-5 provided with a screen adjusting mechanism. Each printing unit has a screen adjustment mechanism (I) 20, (II) 30, and (I)
II) 40 are provided respectively, and these structures
It is known per se. For example, in the present embodiment,
JP-A-3-38784 (JP-A-7-171946)
No.) is exactly the same as that disclosed in
You.

In FIG. 5, the screen 7 is provided on one screen supporting member 50 and a screen receiving plate 50a integral with the screen supporting member 50 by a stopper 52 and an air cylinder 53 on the opposite side, and by positioning bolts 54 and a screen fixing mechanism 55. It is supported by positioning. The opposite screen support member 51 merely receives the screen 7. Therefore, one screen support member 50
Is adjusted in the X, Y, and θ directions in FIG.
Can be adjusted.

Both ends of the screen supporting member 50 are rotatably supported by the adjusting frames 34 and 44 on both sides via height adjusting screws 56 of the screen 7. The upper adjustment frame 44 in the figure is a screen adjustment mechanism (III) 4
With 0, the position is adjusted in the X direction in the figure and the structure is such that it can slide freely in the Y direction in the figure. The lower adjustment frame 34 has a cross structure that can be adjusted in the X direction in the figure by the screen adjustment mechanism (I) 20 and in the Y direction in the figure by the (II) 30.

The structure of each screen adjusting mechanism will be briefly described as follows. Screen adjustment mechanism (I) 20
Is attached to a guide rail extending in the printing width direction outside the screen support member 50, and includes an adjustment motor 21 (MI) and a pulse generator 23 (PGI). The drive shaft of the adjustment motor 21 is Reducer 22 (G
I), connected to the cross slider via a suitable gear mechanism, ball screw and slide bearing.
That is, the cross slider can be slid in the X direction in the figure by the forward / reverse rotation of the adjustment motor 21 (MI), and the displacement amount is detected by the pulse generator 23 (PGI). Screen adjustment mechanism (II) 30
Are mounted on the above-mentioned cross slider, and the adjusting motor 31 (MII) and the pulse generator 33 (PGI
I), the drive shaft of the adjusting motor 31 is connected to an adjusting frame 34 attached to the screen supporting member 50 via a speed reducer 32 (GII), a suitable gear mechanism, and a ball screw slide bearing. ing.
That is, the screen support member 50 is connected to the adjustment motor 31 (M
By the forward / reverse rotation of II), it is possible to slide in the Y direction in the figure, and the displacement amount is detected by the pulse generator 33 (PGII). Therefore, the screen support member 50 is moved by the screen adjusting mechanism (I) 20 described above.
The position is adjusted in the X direction via the cross slider, and the position is adjusted in the Y direction by the screen adjusting mechanism (II) 30. Further, the screen adjusting mechanism (III) 40 has basically the same structure as the screen adjusting mechanism (I) 20, and is attached to a guide rail extending in the printing width direction outside the screen supporting member 50, An adjustment motor 41 (MIII) and a pulse generator 43 (PGIII) are provided. The drive shaft of the adjustment motor 41 is connected to a speed reducer 42 (G
III), it is connected to the adjustment frame 44 attached to the screen support member 50 via a suitable gear mechanism and a ball screw / slide bearing, so that the position can be adjusted in the X direction. That is, the screen support member 50 is rotated by the adjustment motor 41 (MIII) in the normal and reverse directions.
In the figure, it is slidable in the X direction, and the displacement is detected by a pulse generator 43 (PGIII).

As described above, according to the displacement value between the basic data of the register mark of the mother screen and the measured value of the register mark of each textile printing screen, the matching control panel 13
Thus, the adjustment direction and the adjustment amount are instructed and output to the screen adjustment mechanisms 20, 30, and 40 of the printing units 6-1 to 6-5.

Of the respective screen adjustment mechanisms, (I) 2
0 and the (III) 40, the screen 7 moves in the X direction,
The screen 7 is adjusted in the Y direction by the (II) 30 and the screen adjusting mechanism (I) 20 or (III)
By the operation of 40, the rotation of the screen 7 in the θ direction can be adjusted. This operation is schematically illustrated in FIG.

These matching adjustments are performed by the matching control panel 13.
Is performed by a ball screw slide bearing (not shown) by forward / reverse rotation of each of the adjustment motors 21, 31, 41, and the respective adjustment amounts are determined by the pulse generators 23, 33, 43 provided. It is fed back to the control panel 13.

As described above and shown in FIG. 2, the positions of the register marks 7A and 7B and the positions of the patterns 7D of the mother screen 7M and the screens 7 for printing are all made in the same prescribed position. Therefore, by matching the register mark position of the mother screen 7M, that is, the register mark position of each screen with the basic data,
It is possible to obtain the pattern matching of the printed pattern.

In the present invention, the preparatory step for taking in the basic image data of the pattern matching is performed according to the flowchart shown in FIG. 6A, and the step for the pattern printing is shown in FIG. 6B. Each is performed according to the flowchart.

[0055]

According to the present invention, a pattern printing process is performed in a preparation process for capturing and storing basic image data and a process for performing pattern printing in which actual image data is captured. By performing the comparison by image processing, both the detection of the matching state and the adjustment of the matching are automatically performed without requiring any manual operation, so that labor can be saved and productivity can be improved.

In the preparatory step, not only can basic image data of high accuracy be obtained, but also this image data does not change regardless of the frequency of use or aging.
As long as you use the same screen, you can refer to this constantly to provide a good basis for comparison

The detection of the matching state by image processing is extremely accurate compared to the naked eye, has no effect of fatigue like the naked eye, and performs a high-accuracy matching with good reproducibility and stable for a long time. Gives the advantage of gaining.

In the present invention, since the image processing is limited to the register mark having a very small area, there is an advantage that the matching state can be quickly detected even with a small-capacity storage device and a relatively low-speed arithmetic device. .

In the apparatus of the present invention, there is obtained an advantage that the above-mentioned respective mechanisms are organically related to enable automatic pattern matching during the printing process without any loss time.

[Brief description of the drawings]

FIG. 1 is a diagram showing a schematic plane and an outline of control of an automatic screen printing machine according to the present invention.

FIG. 2 is a detailed plan view of a screen used in the present invention.

FIG. 3 is an explanatory diagram of image detection by the CCD camera.

FIG. 4 is an explanatory diagram of a detection comparison and a registration operation of the register mark.

FIG. 5 is an overall plan view of the printing unit.

FIG. 6A is a flowchart of a preparation process of the present invention,
(B) is a flowchart of the pattern printing process.

[Explanation of symbols]

 Reference Signs List 1 machine base 2 front roller 3 rear roller 4 endless belt 5 cloth to be printed 6-1 to 6-5 printing unit 7 screen 7A register mark 7B register mark 7D pattern 7F screen frame 7M mother screen 10A CCD camera 10B CCD camera 11 image Processing device 12 Monitor color television 13 Type control panel 14 Printing machine control panel 20 Screen adjustment mechanism (I) 21 Adjustment motor (MI) 22 Reduction gear (GI) 23 Pulse generator (PGI) 30 Screen adjustment mechanism (II) 31 Adjustment Motor (MII) 32 Reduction gear (GII) 33 Pulse generator (PGII) 34 Adjustment frame 40 Screen adjustment mechanism (III) 41 Adjustment motor (MII) 42 Reduction gear (GIII) 43 Pulse generator (PGIII) 44 Adjustment frame 50 Screen Support member 50a screen receiving plate 51 screen support member 52 stopper 53 et yer cylinder 54 positioned bolt 55 screen fixing mechanism 56 Height adjustment screw

Claims (2)

(57) [Claims] 1. Prior to a printing operation, register marks of the same number as a predetermined number of colors of a printed pattern are printed on a cloth to be printed via a mother screen, and the printed register marks are used as image basic data for image processing. Preparatory process for loading into the device and storing it, and printing using a pattern screen with the register mark engraved at the same position as the register mark on the mother screen, image processing the register mark for each screen after printing as image data The displacement value of the position between the image data and the stored basic image data is detected as the number of dots, and the number of dots of the displacement value is converted into an actual adjustment amount, which is provided for each printing unit. A printing process in which the output is output to a screen adjusting mechanism and the die is adjusted. Mold matching method in a clean printing machine. 2. A register mark of the same number as a predetermined number of colors is formed on both sides in the width direction in correspondence with each color of the printing pattern, and the register marks of the predetermined number of colors are printed on the cloth to be printed prior to the printing operation. Mother screen for pre-printing only the main screen; Design printing screen for main printing in which each register mark is made in the same position as the register mark of the predetermined color on the mother screen; Registered mark provided behind the printing area CCs that capture images as images
D Camera: Register mark pre-printed on the mother screen is stored as basic image data, and this pattern is used for final printing
Register mark image data printed on the screen
An image processing device for detecting and outputting the displacement value of the position between the stored basic image data and the image as a dot number; a computer for converting the dot number of the displacement value into a pulse number corresponding to an actual screen adjustment amount; and the pulse number A screen adjusting mechanism for displacing each of the printing units in accordance with the condition and adjusting the pattern matching.