KR102577055B1 - Error checking device for variable printing substrates - Google Patents

Abstract

The present invention is a variable printing method that implements the manual error inspection method, which used to inspect printouts for errors with the naked eye, as an automatic inspection method that converts an image acquired using a camera into a dot image and then more precisely determines whether an error has occurred. It relates to an error checking device for printed matter, comprising: an image acquisition unit that acquires a captured image by photographing a printed matter through variable printing; and an error inspection unit that checks the presence or absence of error characters in the captured image obtained by the image acquisition unit.

Description

Error checking device for variable printing substrates}

The present invention relates to an error inspection device for variable printed materials. More specifically, the present invention relates to an error inspection device for variable printed materials used in the manufacture of clothing distribution products in the fashion industry, using an image comparison solution to check whether printing defects occur, and to automatically detect the occurrence of printing defects in variable printed materials used in the manufacture of clothing distribution products in the fashion industry. This relates to an error inspection device for variable printed printed matter implemented so that work can be completed when the target quantity is completed without reissuing variable printed matter and setting up equipment.

In general, a line scan camera acquires image data of an object by precisely scanning it for each line of a certain width.

Because of their tight shooting style, line scan cameras are useful for inspecting long objects for defects.

Recently, research is being actively conducted on a print inspection system using a line scan camera to inspect print defects (ink splatter, smear, color error, etc.).

For example, the print inspection system acquires width line image data of the print using a plurality of LED groups of line scan lighting and a line scan camera, and displays the obtained width line image data of the print to determine if the print is defective. (Ink splattering, bleeding, color errors, etc.) were inspected.

Conventional barcode verifiers cost 5 to 12 million won for barcode & Q.R code verifiers for moving labels, and furthermore, there are no domestically produced products.

In addition, the variable manufacturing number defect processing technology such as the production serial number and expiration date of expensive products such as pharmaceutical companies and cosmetics is usually an automatic error number recognition technology through AI learning, which charges a fee every time the production lot number is changed, thus reducing the price. It has the disadvantage of being very high.

In addition, in the case of human inspection, there was a problem in that the printed barcode and alphanumeric contents had to be visually inspected, errors were treated as defects, and the equipment had to be restarted.

Meanwhile, the above-mentioned background technology is technical information that the inventor possessed for deriving the present invention or acquired in the process of deriving the present invention, and cannot necessarily be said to be known technology disclosed to the general public before filing the application for the present invention. .

Korean Patent No. 10-2228081 (announced on March 16, 2021)

One aspect of the present invention is to determine whether printing defects occur in variable printed materials such as 1-dimensional barcode and 2-dimensional QR Code label printing using thermal transfer and inkjet printing methods used in manufacturing clothing distribution products in the fashion industry. We provide an error inspection device for variable printed materials that is inspected using an image comparison solution and automatically reissues variable printed materials when printing defects occur, allowing work to be completed when the target quantity is completed without setting up equipment.

The technical problem of the present invention is not limited to the technical problem mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art from the description below.

An error inspection device for variable printing printed matter according to an embodiment of the present invention includes an image acquisition unit that acquires a captured image by photographing a printed matter through variable printing; and an error inspection unit that checks the presence or absence of error characters in the captured image obtained by the image acquisition unit.

In one embodiment, the error checker compares a first image generated by binarizing an original image of a variable printed matter with a second image generated by binarizing a captured image of an output printed matter obtained through the capturing camera, By reading the range of the area where white dots occur due to the difference in thickness between the original image and the output image, which indicates a printing defect, which is the result of comparing the first image and the second image, it is possible to determine whether the output print is defective. You can.

In one embodiment, the error inspection unit sets and stores the tolerance range of the area where white dots occur in order to read whether the output print is acceptable or not, and when the output print outside the tolerance range is generated, the error inspection unit sets and stores the tolerance range for the area where the white dots occur. The transport device can be controlled to eject printed matter outside the tolerance range from the transport device being transported.

In one embodiment, the error inspection device for variable printing printed matter according to an embodiment of the present invention is installed at a stage prior to the image acquisition unit to improve image quality when capturing an image by the image acquisition unit and is in motion. It may further include a foreign matter removal device that removes foreign matter attached to the printed matter by blowing wind in the same direction.

In one embodiment, the foreign matter removal device includes a conveyor unit that performs an endless orbital movement using a conveyor belt that is installed upwardly and spaced apart from a moving printed matter; Elevating units installed at the front and rear ends of the conveyor unit to lift and move the conveyor unit in an upward and downward direction to adjust the gap between the conveyor belt and the moving printed matter; and a plurality of blowing units installed at regular intervals along the conveyor belt, which move together as the conveyor belt moves and blow wind in the direction of the moving print.

In one embodiment, the blower includes an installation hole formed to penetrate the conveyor belt in a vertical direction; A vibration unit disposed in the installation hole; a unit through hole formed to penetrate the vibration unit in a vertical direction; It is installed to be rotatably driven in the unit through-hole, and when the conveyor belt rotates and the upper opening of the unit through-hole is disposed to face the moving printed matter, it is rotationally driven to open the unit through-hole so that wind is irradiated in the direction of the moving printed matter. A blowing fan that induces air flow through; a support spring installed at the front end of the unit through-hole to support the front end of the vibration unit disposed in the unit through-hole; and a unit support portion installed at the rear end of the unit through hole to support the rear end of the vibration unit.

In one embodiment, the vibration unit may be seated in a sliding guide groove extending in the front-back direction along one side and the other side of the installation hole, and may be provided with sliding guide protrusions on one side and the other side for moving in the front-back direction.

In one embodiment, the unit support unit includes a vibration induction motor installed upright at the rear end of the vibration unit with the drive shaft facing downward; A rotating disc formed in the form of a circular plate and installed by being axially coupled to the drive shaft of the vibration induction motor; an extension frame installed upright on one lower side of the rotating disk; a connection sphere formed in a circular sphere shape and installed on the lower side of the extension frame; and a mounting frame, one end of which is installed at the rear end of the unit through-hole, and the other end of which is connected to the connecting sphere so that it can rotate, to support the rear end of the vibration unit.

In one embodiment, the unit support unit rotates and drives the vibration induction motor together as the blowing fan is driven to vibrate the vibration unit, thereby causing the air discharged through the unit through hole to vibrate. .

According to one aspect of the present invention described above, the manual error checking method, which used to check errors in printed output with the naked eye, is converted into an automatic dot image using a camera to determine more precisely whether an error has occurred. It can be implemented using an inspection method.

In addition, even if some outputs are defective, a continuous printing process can be performed without setting up a printing machine or equipment, which can provide the effect of reducing labor costs.

The effects of the present invention are not limited to the effects mentioned above, and various effects may be included within the scope apparent to those skilled in the art from the contents described below.

1 is a diagram illustrating a schematic configuration of an error inspection device for variable printing materials according to an embodiment of the present invention.
FIG. 2 is a diagram showing the judgment of good quality of an output by the error inspection unit of FIG. 1.
Figure 3 is a diagram showing a comparative solution calculation process by an error inspection device for variable printing printed matter according to an embodiment of the present invention.
Figure 4 is a diagram showing the separation and discharge of defective output by the error inspection unit.
Figure 5 is a diagram illustrating a schematic configuration of an error inspection device for variable printing materials according to another embodiment of the present invention.
FIG. 6 is a diagram showing the foreign matter removal device of FIG. 7.
Figure 7 is a diagram showing the blowing unit of Figure 6.
Figure 8 is a view showing the unit support of Figure 7.

The detailed description of the present invention described below refers to the accompanying drawings, which show by way of example specific embodiments in which the present invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. It should be understood that the various embodiments of the present invention are different from one another but are not necessarily mutually exclusive. For example, specific shapes, structures and characteristics described herein may be implemented in one embodiment without departing from the spirit and scope of the invention. Additionally, it should be understood that the location or arrangement of individual components within each disclosed embodiment may be changed without departing from the spirit and scope of the invention. Accordingly, the detailed description that follows is not intended to be taken in a limiting sense, and the scope of the invention is limited only by the appended claims, together with all equivalents to what those claims assert, if properly described. Similar reference numbers in the drawings refer to identical or similar functions across various aspects.

Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the drawings.

1 is a diagram illustrating a schematic configuration of an error inspection device for variable printing materials according to an embodiment of the present invention.

Referring to FIG. 1, an error inspection device 10 for a variable printed matter according to an embodiment of the present invention includes an image acquisition unit 100 and an error inspection unit 200.

The image acquisition unit 100 acquires a capture image ((c) in FIG. 3) by photographing a printed matter (L) that is continuously output through variable printing in a thermal transfer type printing device (1) such as a label printer. It is then transmitted to the error checking unit 200.

At this time, the printed matter (L) is attached with a label (P) output by the printing device (1), is continuously transferred from the printing device (1) to the label winding device (2), and is placed on the feeding roller (R). It can be moved through the upper side of the shelf 3 installed below the image acquisition unit 100 for photography by the image acquisition unit 100.

Here, the variable print form or type is the product serial number or product number, which may include a Label Tag, Care Label, or Paper Sheet Tag.

The error inspection unit 200 checks the presence or absence of an error character in the captured image obtained by the image acquisition unit 100, and when an error character occurs, it notifies the printing device 1 of this and requests reprinting of the character. .

In one embodiment, the error checker 200 uses the first image ((b) of FIG. 3) generated by binarizing the original image ((a) of FIG. 3) of the variable printed matter and the capturing camera 100. Compare the second image ((d) of FIG. 3) generated by binarizing the captured image ((c) of FIG. 3) of the obtained output printed matter (P), and the first image ((b) of FIG. 3). Reading the range of the area where white dots occur due to the difference in thickness between the original image and the output image, which indicates a printing defect, which is the result of comparison between the and the second image ((d) in Figure 3 ((e in Figure 3) ), (f)), it is possible to read whether the output print (P) is defective.

That is, the error check unit 200 reads a higher defect rate as there are more white dots, as shown in (e) of FIG. 3, and the lower the defect rate as there are no white dots, as shown in (f) of FIG. 3. It will be read.

In one embodiment, the error inspection unit 200 sets the tolerance range (for example, setting the tolerance range to 70%, etc.) of the area where the white dots occur in order to read whether the output printed matter P is acceptable or not. is set and stored, and as shown in FIG. 4, when an output print (P') outside the tolerance range is generated, an output outside the tolerance range is received from the transfer device (3) transporting the output print (P'). The transfer device can be controlled to discharge the printed matter (P').

Accordingly, as shown in FIG. 2, the error inspection unit 200 reads P1 as a good product as the comparison result value is 0.78 (i.e., 78%), and in the case of P2, printing is biased toward the upper side. Accordingly, the comparison result is 0.19 (i.e., 19%), which is interpreted as a defective product. As the printing of P3 is biased toward the upper side, the comparison result is 0.03 (i.e., 3%), which is interpreted as a defective product. You can.

The error inspection device 10 for variable printed matter according to an embodiment of the present invention having the above-described configuration uses an image acquired using a camera to replace the conventional manual error inspection method of output, which had no choice but to inspect errors with the naked eye. After converting to a dot image, it can be implemented as an automatic inspection method that can determine more precisely whether an error has occurred.

Through this, the error inspection device 10 for variable printing printed matter according to an embodiment of the present invention having the above-described configuration allows a continuous printing process to be performed without setting up a printing machine or equipment even if some outputs are defective. , it can provide the effect of reducing labor costs.

FIG. 2 is a diagram showing the error checking unit of FIG. 1.

Referring to FIG. 2 , the error inspection unit 200 includes a capture image processing unit 210, an original image processing unit 220, an image comparison unit 230, and a defect determination unit 240.

The capture image processing unit 210 performs perspective correction, camera lens distortion correction, image area extraction, and an original image corresponding to the original of the printed matter (FIG. 3(c)) obtained from the image acquisition unit 100. The process of adjusting the size to the same size as (a) in Figure 3 and converting the size-adjusted image into the first image ((d) of Figure 3), which is a dot image, is sequentially performed.

The original image processing unit 220 generates a second image by converting an image indicating a place where dots should not be placed in the original image ((a) of FIG. 3) into a dot image, and simultaneously generates a second image by converting the original image ((a) of FIG. 3) into a dot image. In a)), a third image is created by converting the image indicating the place where the dot should be placed into a dot image.

The image comparison unit 230 generates a twelfth image by “ANDing” the first image ((d) of FIG. 3) and the second image, and then performs an “XOR operation” on the twelfth image and the second image to create the twelfth image. 122 images are generated, the 13th image is generated by “ANDing” the first image ((d) of FIG. 3) and the third image, and then the 133rd image is generated by “XORing” the 13th image and the third image. is generated, and the final image ((b) in FIG. 3) is generated by performing an “OR operation” on the 122nd image and the 133rd image.

The defect determination unit 240 expresses the different portions between the captured image ((c) of FIG. 3) and the original image ((a) of FIG. 3) in white in the final image ((b) of FIG. 3), Defectiveness is determined based on the number of white dots (for example, 10 or more white dots), or defectiveness is determined based on the presence or absence of white dots at a specific location.

The error checking unit 200 having the above-described configuration reads that an error has occurred when a white dot is generated as shown in (e) of FIG. 3, and reads that an error has occurred when a white dot is not generated as shown in (f) of FIG. 3. By reading that an error will not occur, the manual error checking method, which used to inspect printed output with the naked eye, is converted into an automatic dot image using a camera to determine more precisely whether an error has occurred. It can be implemented using an inspection method.

Figure 5 is a diagram illustrating a schematic configuration of an error inspection device for variable printing materials according to another embodiment of the present invention.

Referring to FIG. 5 , an error inspection device 20 for variable printed matter according to another embodiment of the present invention includes an image acquisition unit 100, an error inspection unit 200, and a foreign matter removal device 300.

Here, since the image acquisition unit 100 and the error checking unit 200 are the same as the components in FIG. 1, their description will be omitted to avoid duplication of explanation.

The foreign matter removal device 300 is installed in the previous stage of the image acquisition unit 100 to improve image quality when capturing images by the image acquisition unit 100, and blows wind in the direction of the moving print (L). Remove dust and foreign substances attached to the printed matter (L).

The error inspection device 20 for variable printing printed matter according to another embodiment of the present invention having the above-described configuration removes dust, etc. attached to the printed matter L, thereby providing a clearer image by the foreign matter removal device 300. Not only can images be acquired, but print quality can also be improved by producing cleaner prints (L).

Figure 6 is a diagram showing the foreign matter removal device of Figure 5.

Referring to FIG. 6 , the foreign matter removal device 300 includes a conveyor unit 310, an elevating unit 320, and a blowing unit 330.

The conveyor unit 310 performs endless orbital movement using a conveyor belt 311 installed upwardly and spaced apart from the moving printed matter.

The lifting unit 320 is installed at the front end 320-1 and the rear end 320-2 of the conveyor unit 310, respectively, and lifts and moves the conveyor unit 310 in the vertical direction to move it with the conveyor belt 311. Adjust the gap between prints.

A plurality of blowing units 330 are installed at regular intervals along the conveyor belt 311, and move together as the conveyor belt 311 moves and blow wind in the direction of the moving print.

The foreign matter removal device 300 having the above-described configuration blows high-pressure wind in the direction of the printed matter L to remove dust attached to the printed matter L, thereby creating a clearer image by the foreign matter removal device 300. In addition to being able to obtain a cleaner print (L), the print quality can also be improved.

Figure 7 is a diagram showing the blowing unit of Figure 6.

Referring to FIG. 7, the blower 330 includes an installation hole 331, a vibration unit 332, a unit through-hole 333, a blower fan 334, a support spring 335, and a unit support portion 400. Includes.

The installation hole 331 is formed to penetrate the conveyor belt 311 in the vertical direction so that the vibration unit 332 can be placed.

The vibration unit 332 is supported by the support spring 335 and the unit support part 400 and is disposed in the installation hole 331, and a blowing fan 334 is installed inside.

In one embodiment, the vibration unit 332 is seated in a sliding guide groove 331a extending in the front-back direction along one side and the other side of the installation hole 331 and includes a sliding guide protrusion 332a for moving in the front-back direction. Can be provided on one side and the other side.

The unit through-hole 333 is formed to penetrate the vibration unit 332 in the vertical direction, and a blowing fan 334 is installed.

The blowing fan 334 is installed to be rotatably driven in the unit through-hole 333, and when the conveyor belt 311 rotates and the upper opening of the unit through-hole 333 is disposed to face the moving printed matter (L). It is driven in rotation to guide the air flow through the unit penetration hole 333 so that the wind is irradiated in the direction of the moving printed matter (L).

The support spring 335 is installed at the front end of the unit through hole 333 and supports the front end of the vibration unit 332 disposed in the unit through hole 333.

The unit support portion 400 is installed at the rear end of the unit through hole 333 and supports the rear end of the vibration unit 332.

The blower 330 having the above-described configuration removes dust, etc. attached to the printed matter L using compressed air discharged from the vibrating vibration unit 332, and removes dust, etc. from the printed matter L by using the foreign matter removal device 300. Not only can a clearer image be obtained, but the print quality can also be improved by producing a clearer print (L).

Figure 8 is a view showing the unit support of Figure 7.

Referring to FIG. 8, the unit support unit 400 includes a vibration induction motor 410, a rotating disk 420, an extension frame 430, a connecting sphere 440, and a mounting frame 450.

The vibration induction motor 410 is installed upright at the rear end of the vibration unit 332 with the drive shaft facing downward, and drives the rotating disk 420 to rotate.

The rotating disk 420 is formed in the form of a circular plate and is installed by being axially coupled to the drive shaft of the vibration induction motor 410, and rotates the extension frame 430.

The extension frame 430 is installed upright on one lower side of the rotating disk 420, and a connection sphere 440 is installed on the lower side.

The connection sphere 440 is formed in a circular sphere shape and is installed on the lower side of the extension frame 430.

One end of the mounting frame 450 is installed at the rear end of the unit through hole 333, and the other end is connected to a connection sphere 440 so as to be rotatable to support the rear end of the vibration unit 332.

In one embodiment, the unit support unit 400 rotates with the vibration induction motor 410 as the blowing fan 334 is driven to vibrate the vibration unit 332, thereby causing discharge through the unit through hole 333. It can induce the air to vibrate.

The unit support unit 400 having the above-described configuration can not only effectively vibrate the vibration unit 332, but also can rotate the conveyor belt 311 not only when the conveyor belt 311 is placed horizontally. Even when the vibration unit 332 is bent round, the vibration unit 332 can be stably supported and the vibration unit 332 can be prevented from being separated from the installation hole 331.

The above-described embodiments are for illustrative purposes, and those skilled in the art will recognize that the above-described embodiments can be easily modified into other specific forms without changing the technical idea or essential features of the above-described embodiments. You will understand. Therefore, the above-described embodiments should be understood in all respects as illustrative and not restrictive. For example, each component described as unitary may be implemented in a distributed manner, and similarly, components described as distributed may also be implemented in a combined form.

The scope sought to be protected through this specification is indicated by the patent claims described later rather than the detailed description above, and should be interpreted to include the meaning and scope of the claims and all changes or modified forms derived from the equivalent concept. .

10, 20: Error checking device for variable printing printed matter
100: error checking unit
200: error checking unit
300: Foreign matter removal device

Claims (2)

An image acquisition unit that acquires a captured image by photographing a printed matter through variable printing; and
It includes an error checking unit that checks the presence or absence of error characters in the captured image obtained by the image acquisition unit,
It further includes a foreign matter removal device installed in a previous step of the image acquisition unit to remove foreign substances attached to the printed matter by blowing wind in the direction of the moving printed matter to improve image quality when capturing images by the image acquiring unit. And
The foreign matter removal device,
A conveyor unit that performs endless orbital movement using a conveyor belt installed upwardly from the moving printed matter;
Elevating units installed at the front and rear ends of the conveyor unit to lift and move the conveyor unit in an upward and downward direction to adjust the gap between the conveyor belt and the moving printed matter; and
It includes a plurality of blowing units installed at regular intervals along the conveyor belt, which move together as the conveyor belt moves and blow wind in the direction of the moving print,
The blower unit,
An installation hole formed to penetrate the conveyor belt in the vertical direction;
A vibration unit disposed in the installation hole;
a unit through hole formed to penetrate the vibration unit in a vertical direction;
It is installed to be rotatably driven in the unit through-hole, and when the conveyor belt rotates and the upper opening of the unit through-hole is disposed to face the moving printed matter, it is rotationally driven to open the unit through-hole so that wind is irradiated in the direction of the moving printed matter. A blowing fan that induces air flow through;
a support spring installed at the front end of the unit through-hole to support the front end of the vibration unit disposed in the unit through-hole; and
It includes a unit support part installed at the rear end of the unit through hole to support the rear end of the vibration unit,
The vibration unit is,
A sliding guide protrusion is provided on one side and the other side of the installation hole to be seated in a sliding guide groove extending in the front-back direction along one side and the other side of the installation hole and to move in the front-back direction,
The unit support part,
A vibration induction motor installed upright at the rear end of the vibration unit with the drive shaft facing downward;
A rotating disc formed in the form of a circular plate and installed by being axially coupled to the drive shaft of the vibration induction motor;
an extension frame installed upright on one lower side of the rotating disk;
a connection sphere formed in a circular sphere shape and installed on the lower side of the extension frame; and
An error inspection device for a variable printed matter comprising; a mounting frame, one end of which is installed at the rear end of the unit through-hole, and the other end of which is connected to the connecting sphere to be rotatable, and which supports the rear end of the vibration unit.
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