JP2001225453A - Inspecting device for printed matter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inspecting device for printed matters which issues an alarm, with which an operator of a printing machine can immediately judge the kind of a defect in hearing the alarm, resulting in bringing no delay in dealing with the cause of inferiority. SOLUTION: The inspecting device for printed matters has a defect detecting means, which judges the existence of defects and their kinds so as to output a detection signal, and an alarming means for alarming the kind of the defect with a defect specifying sound on the basis of the detection signal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention belongs to the technical field of inspecting printed matter. In particular, determine the type of detected defect,
The present invention relates to a printed matter inspection device that warns with a sound corresponding to the type.

[0002]

2. Description of the Related Art In a conventional printed matter inspection apparatus, for example, when a defect is detected, an alarm is sounded, and a captured image of the printed matter in which the defect is detected or a defect image derived from the image is displayed on a display monitor. .
Upon hearing the alarm, the operator of the printing press looks at the image displayed on the display monitor, determines the type of defect, and takes action such as coping with the cause of the defect.

[0003]

That is, the operator of the printing press has to go to the image displayed on the display monitor in order to know what kind of defect has been detected. This operation can be an impossible operation when the operation of the printing press is busy, and is a heavy load if not impossible. In addition, since it takes a considerable amount of time to determine the type of defect, there is a problem in that measures for the cause of the defect are delayed, and waste paper (defective printed matter) increases.

The present invention has been made to solve such a problem, and an object of the present invention is to allow a printing press operator who has heard an alarm to immediately determine the type of defect and to cope with the cause of the defect. It is an object of the present invention to provide a printed matter inspection device that does not delay the printing.

[0005]

The above object is achieved by the present invention described below. That is, a printed matter inspection apparatus according to claim 1 of the present invention includes a defect detection unit that determines a type of a defect and the type of the defect and outputs a detection signal, and a defect identification unit that specifies the type of the defect based on the detection signal. And an alarm means for giving an alarm by sound. According to the present invention, the presence of a defect is determined by the defect detection unit and the type of the defect, and a detection signal is output, and the warning unit issues a warning with a defect specifying sound for specifying the type of the defect based on the detection signal. Therefore, the operator of the printing press that has heard the alarm can immediately determine the type of the defect, and a printed matter inspection apparatus that does not delay the handling of the cause of the defect is provided.

According to a second aspect of the present invention, there is provided the printed matter inspecting apparatus according to the first aspect, wherein the defect detecting means detects a raw material defect existing in the raw material, and the alarming means detects the raw material defect. An alarm is issued by the defect specifying sound for specifying an anti-defect. According to the present invention, the defect detecting means detects the raw material defect present in the raw material, and the warning means gives a warning with a defect specifying sound for specifying the raw material defect. Accordingly, the original defect can be distinguished from other defects by the alarm.

According to a third aspect of the present invention, there is provided the printed matter inspection apparatus according to the first or second aspect, wherein the defect detecting means detects a light stain defect existing in the printed matter, and the alarm means comprises An alarm is issued by the defect specifying sound for specifying a light stain defect. According to the present invention, the defect detection means detects a light stain defect existing in the printed matter, and the alarm means gives an alarm with a defect specifying sound for specifying the light stain defect. Therefore, a thin stain defect can be distinguished from other defects by an alarm.

The printed matter inspection apparatus according to a fourth aspect of the present invention is the printed matter inspection apparatus according to any one of the first to third aspects, wherein the defect detecting means detects a streak defect existing in the printed matter and outputs the alarm. The means is configured to give an alarm with a defect specifying sound for specifying the stripe stain defect. According to the present invention, the stripe detection defect existing in the printed matter is detected by the defect detection unit, and the warning is issued by the warning unit with a defect specifying sound for specifying the stripe contamination defect. Therefore, a streak stain defect can be distinguished from other defects by an alarm.

According to a fifth aspect of the present invention, there is provided the printed matter inspecting apparatus according to any one of the first to fourth aspects, wherein the defect detecting means detects a spot stain defect present in the printed matter and outputs the alarm. The means is configured to give an alarm with a defect specifying sound for specifying the point contamination defect. According to the present invention, the defect detection unit detects a spot stain defect existing in the printed matter, and the alarm unit issues an alarm with a defect specifying sound for identifying the spot stain defect. Therefore, the point stain defect can be distinguished from other defects by the alarm.

[0010]

Next, an embodiment of the present invention will be described. FIG. 1 shows an example of the configuration of the printed matter inspection apparatus of the present invention. In FIG. 1, 1 is a printing unit, 2
, A paper feed unit; and 3, a paper discharge unit. These are the parts that make up the printing press. Reference numerals 4 and 5 denote imaging means, 6 denotes a raw material inspection processing unit, 7 denotes a print inspection processing unit, and 8 denotes an output processing unit.
These are parts that constitute the printed matter inspection device. Also,
In the print inspection processing unit 7, reference numeral 11 denotes a light stain defect detection processing unit, reference numeral 12 denotes a stripe stain defect detection processing unit, and reference numeral 13 denotes a point stain defect detection processing unit. Also, 14, 15, 16, 17, 18
Is a speaker.

The printing press schematically shown in FIG. 1 shows a printing press such as an offset printing press, a gravure printing press, a flexographic printing press, etc., and the present invention is not limited by a printing method. In a part constituting the printing press, the printing unit 1
Are 4 to 6 in a typical multicolor printing press. FIG.
In the example shown in (1), the web unwound from the winding body in the paper feeding unit 2 is printed in the printing unit 1 and wound up in the paper discharging unit 3 to form a winding body. Paper feed unit 2
Is a raw material, that is, a roll of printing paper, plastic film, metal foil, or the like. Further, the winding body of the paper discharge unit 2 is a printed material having its surface printed.

The image pickup means 4 picks up an image of the surface of the web immediately before being unwound from the winding body in the paper feeding section 2 and fed to the printing unit 1. That is, it is an imaging means for imaging the surface of the raw material, and the raw material inspection is performed based on the captured image. The imaging unit 5 captures an image of the surface of the web immediately before being discharged from the printing unit 1 and wound up in the paper discharge unit 3 to become a winding body. That is, it is an image pickup unit that picks up an image of the surface of the printed matter, and print inspection is performed based on the picked-up image.

The raw material inspection processing section 6 inputs an image of the raw material (raw material image) captured by the imaging means 4. Then, data processing is performed on the input source image to extract defects existing in the source material. Although the form of data processing differs depending on whether the original is a solid raw with no pattern or an original with a pattern, the present invention is not limited by the form of data processing. In the case of an original having a picture, data processing in the print inspection processing unit 7 described below can be applied. Therefore, here, an example of data processing in the case of a plain fabric having no picture will be described.

Defects existing in the plain fabric include dirt,
Foreign matter, pinholes, etc. These defects have different light reflection characteristics from the normal part of the plain fabric. Therefore, a process of extracting a defect from the difference in the reflectance of light between the defective portion and the surrounding normal portion is performed. For example, a defect is extracted by performing data processing for binarizing the original image with a predetermined threshold value. Further, in order to perform defect extraction with higher sensitivity, as a process for eliminating the effects of illumination unevenness and sensitivity unevenness in the imaging system and for emphasizing a difference in light reflectance, a differential process with respect to the original film image is performed. After performing the data processing, the data processing for binarizing with a predetermined threshold value is performed to extract the defect.

The predetermined threshold is not limited to a fixed threshold. For example, a histogram of pixel values (corresponding to reflectance and brightness) in an original image can be obtained, and a pixel value whose cumulative distribution is a predetermined percentage can be used as a threshold. In addition, a histogram of pixel values in the original image is obtained, and if the histogram is bimodal, the pixel value of the valley can be used as the threshold. Further, the average value of the pixel values in a predetermined range in the original web image can be used as the threshold.

The print inspection processing section 7 inputs a picked-up image (printed image) of a printed matter picked up by the image pickup means 5.
Then, data processing is performed on the input print image to extract a defect existing in the printed matter. The print image is generally an image having a design. The data processing in this case is
Data processing for extracting a defect by comparing a captured image of a normal (non-defective) printed material as a reference image and comparing the reference image with an inspection target image which is a captured image of the inspection target printed material is performed. For example, after performing data processing for correcting a shift in the imaging position between the reference image and the inspection target image, a difference image is generated by calculating a difference in pixel value for each corresponding pixel. Then, data processing for extracting a defect existing in the printed matter is performed on the difference image.

The defects existing in the printed matter include color tone fluctuations, light-stain defects having low density, streak defects which are streaks extending in the transport direction of the web, and spot-flaw defects which are dot-like stains. , Etc. There is a form of data processing suitable for each defect characteristic, and data processing for extracting a defect is different.

A process for extracting a light stain defect will be described. The above-described difference image is subjected to an integration process for obtaining a sum of pixel values for each predetermined region to obtain an integrated value. If the integrated value falls within a predetermined allowable range, it is determined that there is no light stain defect, and if it is out of the allowable range, it is determined that there is a light stain defect.

A process for extracting a streak defect will be described. Differential processing is performed on the difference image in the width direction of the web (the direction orthogonal to the transport direction) to obtain a differential image.
Next, the differential image is subjected to integration processing for obtaining the sum of pixel values in the longitudinal direction (transfer direction) of the web, thereby obtaining an integrated value. If the integrated value falls within a predetermined allowable range, it is determined that there is no streak defect, and if it is outside the allowable range, it is determined that a streak defect exists.

The process of extracting a point-stain defect will be described. The above-described threshold value is calculated and obtained for each of the predetermined regions for the above-described difference image. The difference image is set to 2
Then, the number of pixels whose pixel value exceeds the threshold value is counted for each predetermined area to obtain a count value. If the counted value falls within a predetermined allowable range, it is determined that there is no point stain defect, and if it is out of the allowable range, it is determined that a point stain defect exists.

The output processing unit 8 inputs inspection data obtained as a result of processing the picked-up image and extracting defects by the raw material inspection processing unit 6 and the print inspection processing unit 7. That is, inspection data relating to the presence / absence of a source defect, a light stain defect, a stripe stain defect, and a spot stain defect, and the location of the defect in the printed matter are input. If the defect position of the inspection data output by the print inspection processing unit 7 matches the defect position of the inspection data output by the raw material inspection processing unit 6, the output processing unit 8 indicates that the defect is an original defect. Then, an alarm is issued from the speaker 18.

If the defect position of the inspection data output by the print inspection processing unit 7 does not match the defect position of the inspection data output by the raw material inspection processing unit 6, the output processing unit 8 outputs The type of the defect is determined. That is, it is determined whether each of the light stain defect, the stripe stain defect, and the spot stain defect is a single defect, or a combined defect in which two or more of the defects are combined. Then, the output processing unit 8 issues a warning from the speaker 14 in the case of a single defect including only a light stain defect. The output processing unit 8 issues a warning from the speaker 15 in the case of a single defect including only a stripe stain defect. Further, the output processing unit 8 issues a warning from the speaker 16 in the case of a single defect including only a spot dirt defect. Further, the output processing unit 8 issues an alarm from the speaker 17 when the composite defect is detected.

The loudspeaker 14 gives an alarm with a tone for specifying a light stain defect or a synthesized voice saying "light stain defect has occurred!". The loudspeaker 15 gives an alarm with a tone specifying the stripe stain defect or with a synthesized voice saying "string stain defect has occurred!" The loudspeaker 16 gives an alarm with a tone specifying the point dirt defect or with a synthesized voice saying "point dirt defect has occurred!" The loudspeaker 17 gives an alarm with a tone specifying the composite dirt defect, or with a synthetic voice saying "Complex dirt defect has occurred!" The loudspeaker 18 gives an alarm with a tone specifying the source material contamination defect or with a synthesized voice saying "Original material contamination defect has occurred!"

The above-mentioned alarm continues without interruption as long as the defect exists continuously. In the case of a transient defect, the alarm is automatically stopped after an alarm is given for a predetermined time. Note that all the inspection data is stored in a storage unit (not shown) of the printed matter inspection apparatus. The inspection data stored in the storage unit can be displayed on a display monitor. Therefore, even after the alarm stops, the operator can check the contents of the inspection data on the display monitor and take necessary measures.

[0025]

According to the printed matter inspection apparatus according to the first aspect of the present invention, the operator of the printing press that has heard the alarm can immediately determine the type of the defect, and does not delay the handling of the cause of the defect. A printed matter inspection device is provided. Further, according to the printed matter inspection apparatus according to the second aspect of the present invention, the original defect can be distinguished from other defects by the alarm. Further, according to the printed matter inspection apparatus according to the third aspect of the present invention, it is possible to discriminate a light stain defect from other defects by an alarm. Further, according to the printed matter inspection apparatus according to the fourth aspect of the present invention, a stripe stain defect can be distinguished from other defects by an alarm. Further, according to the printed matter inspection apparatus according to the fifth aspect of the present invention, a spot stain defect can be distinguished from other defects by an alarm.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an example of a configuration of a printed matter inspection apparatus according to the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 printing unit 2 paper feed unit 3 paper discharge unit 4, 5 imaging means 6 raw material inspection processing unit 7 print inspection processing unit 8 output processing unit 11 light stain defect detection processing unit 12 stripe stain defect detection processing unit 13 point stain defect detection Processing unit 14, 15, 16, 17, 18 Speaker

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hideto Sakata 1-1-1, Ichigaya-Kagacho, Shinjuku-ku, Tokyo Inside Dai Nippon Printing Co., Ltd. (72) Inventor Yasutaka Fujii 1-chome, Ichigaya-cho, Shinjuku-ku, Tokyo No. 1-1 F-term in Dai Nippon Printing Co., Ltd. (reference) 2C250 EA12 EB43 2G051 AA34 AB01 AB02 AB04 CA03 CA04 CA07 CB01 DA06 EA08 EA09 EA11 EA14 EB01 EB02 EC01 EC02 EC03 ED07 FA10 5B057 AA11 BA02 BA11 DA03 DC23 DB02

Claims (5)

[Claims] 1. A defect detecting means for judging the type of a defect together with the type of the defect and outputting a detection signal, and an alarming means for alarming with a defect specifying sound for specifying the type of the defect based on the detection signal. A printed matter inspection apparatus, characterized in that: 2. The printed matter inspection apparatus according to claim 1, wherein
The defect detection means detects a source defect present in the source,
The printed matter inspection apparatus according to claim 1, wherein the warning unit issues a warning with the defect specifying sound for specifying the material defect. 3. The printed matter inspection apparatus according to claim 1, wherein said defect detecting means detects a light stain defect existing in the printed matter, and said alarm means gives an alarm with said defect specifying sound for identifying said light stain defect. A printed matter inspection device. 4. A printed matter inspection apparatus according to claim 1, wherein said defect detecting means detects a streak defect present in the printed matter, and said alarm means specifies said streak stain defect. A printed matter inspection device characterized by sounding an alarm. 5. A printed matter inspecting apparatus according to claim 1, wherein said defect detecting means detects a spot stain defect existing in the printed matter, and said alarm means identifies said spot stain defect. A printed matter inspection device characterized by sounding an alarm.