JPH09226098A - Print check method, device therefor and monitoring device for print check device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To automatically determine a shift in the print position with high reliability by using ink color data printed initially as master data, based on one of the color imaging signals from a highlighted print part for detecting a shift in the print position, and comparing data on each of checked ink colors to master data. SOLUTION: A color imaging signal for a print registering mark imaged by a color television camera 28 is normalized by a gain correction circuit 41, so that a distinguishing process is performed for decomposition per ink color using a color conversion circuit in a print registration evaluation device 51. The ink color data is stored in master memory 53. This ink color data is temporarily stored in YMCK memory 54 at the time of checking, and data stored in these memory units 53, 54 is supplied to a comparison/calculation circuit 55. Then the shift size of the print position obtained from this circuit 55 is supplied as a registration evaluation signal to a color still image display device 37, and this color still image is displayed in a color TV set 40 for monitoring. Finally the shift in the print position is adjusted by a print controller.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a print inspection device that guarantees the print quality of a printed matter printed by a printing device such as a rotary printing machine or a sheet-fed printing machine that performs color printing with a plurality of color inks. The present invention relates to a print inspecting method and an apparatus therefor capable of automatically inspecting a deviation (color misregistration) of a printing position of each ink color, and a monitoring apparatus for the apparatus.

[0002]

2. Description of the Related Art Offset printers and gravure printers use Y (yellow) ink, M (magenta) ink, C
(Cyan) ink and K (black) ink are always used as basic ink colors to perform color printing.

The inspection of the printing position deviation of the printed matter produced by these printing apparatuses is carried out at the time of printing, by manually pulling out the printed matter by an operator, and one end in the width direction of the printed matter on the inspection table. Print position misalignment detection printing section attached only to the copy (in other words, it is a printing register mark, which is usually called a register mark, and is generally called a "ten" register that is printed in layers for each ink color. The mark is often used.) Is visually checked using a magnifying glass.

During the actual printing after such a printing inspection, a color television camera for monitoring installed on the delivery side of the printing line instantaneously takes an image of the register mark under stroboscopic light emission, and the color image is taken. The signal is visualized on a monitor color display, enlarged and displayed as a color still image, and the still image is visually checked to determine the quality of the print position deviation. Generally, if the printing position deviation (color deviation) is within 100 μm, it is permissible. If the color deviation is 100 μm or more, the contour of the print looks blurry, and the operator judges that the printing is defective. ing.

Further, the following printing monitoring device is known in order to know the quality of the printing at the time of actual printing, although it is not an inspection of the printing position deviation. This monitoring device uses a monitoring color TV camera installed on the delivery side of the printing line with a zoom mechanism, and this camera
It is attached so as to be movable along a traverse rail that extends in the width direction of the printed matter. Then, while manually moving the camera to an arbitrary traverse position, the zoom mechanism is set to a desired angle of view by remote control operation, the printing surface is instantaneously imaged under flash light emission, and the color image pickup signal is used as a monitor color image. It is visualized on the display and enlarged and displayed as a color still image. Therefore,
By visually checking this color still image, the operator is allowed to judge the quality of printing.

Similarly, a defect inspection device for displaying the detected defect in color is also known, although it is not an inspection of the print position deviation. This inspection device scans the printed matter in the width direction with a defect detection television camera, processes the defect image pickup signal from this camera with the defect detection device, and detects whether or not there is a defect in the printed matter, and detects the defect. It is measured at which position in the widthwise direction the printed defect is located. Then, the position information of the defect is given to the monitoring device arranged on the downstream side in the moving direction of the printed matter with respect to the defect detection TV camera, and the monitoring color TV camera with a zoom function of the monitoring device is traversed. The defect detected by the camera is moved to a predetermined position to pass through, the defect detected by the camera is momentarily imaged at the predetermined position under stroboscopic light emission, and the color image pickup signal is visualized on a monitor color display to color stop. The image is enlarged and displayed. Therefore, the operator can monitor and monitor the detected defect by visually checking the color still image.

[0007]

As described above, in the conventional inspection of the print position shift, the operator monitors the color still image displayed on the monitor color display even if the inspection is not a problem. The quality of the print position deviation is determined based on the operator's judgment. Further, the print monitoring device or the defect inspection device that traverses the color television camera in the width direction of the printed matter to monitor the defects that have been printed or detected as a color still image can change the traverse range of the color television camera. For example, it is conceivable that it is possible to capture an image of the print registration mark for detecting the print position deviation and display it as a color still image, but even in that case, the quality judgment of the print position deviation is left to the operator's judgment. There is no change.

However, in such a judgment, not only the influence of the sensitivity of the same operator is greatly reflected in the quality judgment which is regularly carried out even by the same operator, but also the displacement size of each ink color is not measured. As a result, it is not possible to accurately know the specific situation of the print position deviation, and therefore there is a problem that the reliability of the quality judgment of the print position deviation is low.

If it is assumed that the print monitoring device or the defect inspection device captures the print register mark, the color television cameras provided in these devices have zooming set immediately before capturing the print register mark. Since the print register mark is imaged in accordance with the enlargement ratio, it is very likely that the image will be taken at a different enlargement ratio each time the image is taken, and there is a marked difference in size between the defect and the print register mark. Therefore, it is necessary to change the enlargement ratio inevitably. However, when the size of the angle of view is different as described above, the standard cannot be secured when the print position deviation of each ink color is to be measured based on the color still image on the monitor color display.

Therefore, a first problem to be solved by the present invention is to provide a print inspection method and apparatus capable of automatically and reliably determining the quality of a print position deviation of a color printed matter.

Further, as described above, the conventional quality judgment of the print position deviation is made only by visually observing the print register mark provided only on one end portion in the width direction of the printed matter on the monitor color display. Therefore, since the quality judgment of the print position deviation on the other end side in the width direction of the printed matter is entrusted to the visual observation of the color still image of the printing obtained by the print monitoring device or the like, this judgment is not actually made. Are equal.

Therefore, as is often seen in gravure printing, the elongation at both ends of the rotary printing base paper is different, or the thickness of each part of the rotary printing base paper to be printed is not uniform and there is a thickness difference in the thickness direction. In some cases, if a printing misregistration defect occurs on the other end side, there is a high possibility that printing on the other end side half in the width direction of the printed matter that has been subjected to corner printing will be bad. Further, as described above, if there is a thickness difference, the printed matter is likely to skew, but there is a problem that such skew occurrence information cannot be obtained.

Therefore, a second problem to be solved by the present invention is to solve the first problem and to obtain print position deviation information effective for reducing the occurrence of print defects due to the print position deviation. In addition to the above, it is an object of the present invention to provide a print inspection device capable of obtaining skew occurrence information of a printed matter.

By the way, the conventional inspection of the printing position deviation is nothing but the monitoring device of the printing register mark as described above. In addition, the printing monitoring device that monitors only the printing unit,
It does not have the ability to detect and monitor defects. Further, the defect inspection device only monitors defects, and cannot monitor the print registration mark.

However, in performing color printing, it is important to determine whether the printing position is defective or not, and to determine whether the automatically detected defect is defective. To satisfy both of these, each device must be provided individually. Therefore, there is a problem that the burden on the equipment becomes large.

Therefore, a third problem to be solved by the present invention is to provide a print inspection device which can determine the quality of a defect which is automatically detected with a small equipment load while achieving the first problem. is there.

A fourth problem to be solved by the present invention is a monitor for a print inspection apparatus suitable for detecting monitor information for determining the quality of a print position deviation and the quality of an automatically detected defect. To provide a device.

[0018]

In order to solve the first problem, the invention method of claim 1 is to detect a print position deviation applied to each of the inks on a printed matter color-printed with a plurality of color inks. An image of the target printing part for the image is picked up by a color television camera for monitoring with a fixed angle of view, the color image pickup signal output from this camera is discriminated for each ink color, and at least the first printed ink among them is detected. Ink color data is used as master data, and then, the color image pickup signal obtained by the camera for the target printing section to be inspected is discriminated for each ink color to create inspected data for each ink color. It is characterized in that the data to be inspected is compared with the master data to obtain the print position deviation dimension for each ink color.

In the method according to the first aspect of the present invention, the color image pickup signal for the target printing portion to be inspected is discriminated for each ink color to obtain inspected data for each ink color, and these inspected data are obtained. Since it is compared with the master data, it is possible to detect the print position deviation with respect to the reference position for each ink color, and both data are obtained by processing the color image pickup signals picked up by the same color TV camera with a constant angle of view. The reference can be secured, and the print position deviation dimension for each ink color can be obtained.

Similarly, in order to solve the first problem,
The invention device according to claim 2 is a monitoring color television camera for picking up, at a constant angle of view, a target printing portion for printing position deviation detection, which is attached to each of the inks on a printed matter that is color-printed with a plurality of color inks. A color conversion unit for distinguishing the color image pickup signal of the camera for each ink color for the target print unit, a monitor color display for visualizing the color image pickup signal and displaying a still image, and the target print unit on the display. Master recording means for fetching and saving ink color data for each ink color discriminated by the color conversion means as master data when the color still image of (1) satisfies the reference condition; For each ink color obtained by discriminating by the color conversion means a color image pickup signal output from the color television camera that has imaged the target printing portion. Comparison for obtaining the print position deviation dimension for each ink color by comparing the master data for each ink color and the inspection data for each ink color with the YMCK recording means for fetching and temporarily storing the inspection data -It is equipped with a calculation means.

According to another aspect of the present invention, the surveillance color television camera captures an image of the printing portion of interest for detecting the printing position deviation attached to the color printed matter. This imaging is always performed at a constant angle of view, thereby ensuring the measurement reference in the comparison / calculation described later. In the target printing portion, a printing register mark printed on the end portion in the width direction of the printed material with each ink, or alternatively, a characteristic printing that is a part of the printing portion and is printed using all the ink Parts are used.

The color conversion means discriminates the color image pickup signal from the camera supplied thereto for each ink color.
In this discrimination, color separation is performed to discriminate which ink color the RGB image information of the print portion of interest is made of. The monitor color display visualizes the color image pickup signal from the camera and displays it on the screen as a color still image. The master recording means acquires ink color data for each color-separated ink color as master data when the color still image satisfies the reference condition, that is, when it is recognized that there is substantially no print position deviation. Save in a mix.

The YMCK recording means temporarily stores the inspected data for each ink color obtained by discriminating the color image pickup signal by the color conversion means, for example, until the next non-inspection data is supplied. The comparison / calculation means compares the master data for each ink color with the data to be inspected for each ink color individually corresponding to the master data, and performs calculation for measuring the print position deviation dimension for each ink color. .

Therefore, in this print inspection apparatus, the color image pickup signal of the printing portion of interest captured by the monitoring color television camera at a constant angle of view is displayed on the monitor color display as a color still image. By visually recognizing the image, it is possible to visually check whether or not there is a print position shift in the target print portion. on the other hand,
Since the color image pickup signal, in other words, the RGB image information, is also supplied to the color conversion unit, the target printing unit is separated for each ink color by the discrimination function of this conversion unit. Then, as a result of the visual check by the operator, if it satisfies the reference condition that can be evaluated as master data, along with the instruction operation by the operator, the color image pickup signal satisfying the reference condition is supplied for each ink color. Each ink color data obtained by the discrimination is taken in and stored in the master recording means as master data which becomes a reference for comparison which will be described later.

After the master data is stored at the time of such printing, the main printing is performed, whereby the printed image of the printed matter is picked up by the color television camera, and the color image pickup signal is discriminated by the color conversion means. Then, the data to be inspected for each ink color is formed. The data to be inspected for each ink color is recorded in the YMCK recording means,
It is temporarily stored until the next data to be inspected is supplied.

The data to be inspected and the master data are read by the comparison / calculation means. Here, comparison is made for each ink color, that is, the master data that is the basis of comparison and the corresponding ink color data are compared, and the ink color that is compared with the master data based on the comparison. The shift size of the print position of the data is calculated.

Therefore, in this print inspection apparatus, for each of a plurality of ink colors printed on the print portion of interest of the printed matter, in which direction and how much the ink is displaced with respect to the reference print position. Can be automatically determined.
The criterion in this determination does not change with each determination because the angle of view of the color television camera for obtaining the master data and each ink color data is constant.

In order to solve the second problem,
The invention device according to claim 3 is the monitoring color television camera, color conversion means, master recording means, YMCK recording means,
And the color television camera provided with the first and second print inspection systems provided with comparison / calculation means, of which the first print inspection system is provided, at the one end in the width direction of the printed matter. Place the printing unit in a position where you can image
The color television camera included in the second print inspection system is arranged at a position where the target print portion attached to the other widthwise end of the printed matter can be imaged.

The first and second print inspection systems according to the third aspect of the present invention respectively include a monitoring color television camera, a color conversion unit, a master recording unit, a YMCK recording unit, and a comparison / comparison unit.
The third aspect of the invention can also solve the first problem because the system inspection device is provided with a computing means and these system components have the same operation as the printing inspection apparatus of the second aspect of the invention. In addition, the first print inspection system inspects the target print portion attached to one end of the printed matter in the width direction, and the second print inspection system inspects the target print portion attached to the other end of the printed matter in the width direction. It is possible to determine whether or not the print position deviation is good for each ink color with respect to both widthwise end portions of the printed matter.

According to the quality judgment of the printing position deviation at the both widthwise end portions of the printed matter, when the elongation in the width direction of the rotary printing base paper is different, or the thickness of each portion of the rotary printing base paper to be printed is not uniform. In the case where there is a thickness difference in the thickness direction, a printing position deviation defect may occur on the other end side,
Since such information can be obtained when the printed matter is skewed based on the thickness difference, it is possible to take early measures to avoid the printing position shift and the skew of the printed matter by using the detected information. You can

In order to solve the third problem,
The invention apparatus according to claim 4 is arranged for defect detection, which is arranged with a defect detection position where a printed matter color-printed with a plurality of color inks is conveyed as a visual field, and which scans the printed matter conveyed to the defect detection position in the width direction. A television camera and a defect image pickup signal supplied from the television camera are processed to determine whether the printed matter is good or bad, and when it is determined that there is a defect, the position of the defect in the width direction of the printed matter is measured. The defect detection device and a defect monitoring position defined on the downstream side of the defect detection position in the conveying direction of the printed matter are arranged as a field of view, and move in the width direction of the printed matter over the entire width of the printed matter or more. The monitoring color television camera is provided freely, and the monitoring color television camera has the defect according to the defect position information supplied from the defect detection device. When the defect passes through the planned position, the predetermined area including the defect is enlarged and imaged by the camera, and the monitoring color television camera is periodically attached to the printed matter. The specified area including the noted printing section is moved to a position deviation detection scheduled position through which the noted printing section for printing position deviation detection passes, and when the noted printing section passes the positional deviation detection position by this camera. A monitoring device for enlarging and imaging, a color still image display device for visualizing a color imaging signal from the monitoring color television camera and displaying it on a monitor display as a color still image, and a color imaging signal for the target printing unit are processed. And a registration register evaluation device for measuring the deviation of the printing position, wherein the monitoring device includes a monitoring color television camera and the camera. At least one first lens fixed focus is combined look for imaging the disadvantages at high resolution, the second one fixed focus expanding imaging the target printing unit in combination with the color television camera
It is characterized in that it has a lens and a lens exchange mechanism for selecting these lenses.

In the invention of claim 4, the defect detecting television camera scans the printed matter conveyed to the print defect detecting position in the width direction and supplies it to the defect detecting device as a defect image pickup signal. This detection device not only processes the defect image pickup signal to detect a defect during printing and determines whether the defect is good or bad, but also measures whether or not the defect is at a degree position in the width direction of the printed matter to detect the position of the defect. get information.

The color television camera for monitoring, which is movable in the width direction of the printed matter, picks up the defect detected by the defect detecting device through this lens when the first lens is selected by the lens exchange mechanism. In this imaging, the color television camera moves in advance to a position where the defect passes, according to the position information of the previously detected defect, and images the defect at that position, and the angle of view in the imaging has a high resolution. Is fixed with a fixed focus. However, when there are a plurality of first lenses, a high resolution can be selected according to each.

Further, the color television camera periodically selects the second lens by its lens exchange mechanism, moves in advance to a position where the target printing unit passes, and passes the second lens at that position through the second lens. Image. Since the angle of view in this imaging is predetermined with a fixed focus so as to obtain a required resolution, it is possible to secure the measurement reference in the later-described print evaluation. In the target printing portion, a printing register mark printed on the end portion in the width direction of the printed material with each ink, or alternatively, a characteristic printing that is a part of the printing portion and is printed using all the ink Parts are used.

The color still image display device displays the color image pickup signal supplied from the surveillance color television camera as a color still image on the monitor color display. Therefore, the color image of the defect is enlarged and displayed as a still image at a high resolution on the display of this device.

The print registration evaluation apparatus processes the color image pickup signal for the target print section supplied from the color television camera to measure the deviation of the print position. Therefore,
According to the fourth aspect of the present invention, the print portion of interest can be periodically imaged through the second lens of the monitoring device, and the color image pickup signal can be processed by the print register evaluation device to automatically measure the print position deviation. In addition, the defect image pickup signal obtained by the defect detection television camera is processed by the defect detection device to automatically detect the defect during the measurement of the print position deviation, and the defect is imaged through the first lens of the monitoring device. Since it is enlarged and displayed as a color still image on the monitor display with a high resolution by the color thread drawing display device, the color still image of the defect automatically detected on the display can be visually recognized.

As described above, according to the invention of claim 4, the same monitoring device and the color still image device can be shared so that the automatically detected defect can be visually recognized as a color still image, and the printing register mark and the like can be visually recognized. It is possible to monitor the printing portion of interest and measure the size of the printing position shift.

[0038] Similarly, in order to solve the third problem, in the invention device according to claim 5, the print register evaluation device outputs a color image pickup signal of the monitoring color television camera for the target print portion. Color conversion means for discriminating each ink color, and ink for each ink color discriminated by the color conversion means when the color still image of the noted printing section on the monitoring color display satisfies a reference condition. A master recording unit that captures and stores color data as master data, and a color image pickup signal that is output from the color television camera that has captured the target printing unit after storing the master data is obtained by discriminating by the color conversion unit. YMCK recording means for fetching and temporarily storing display data for each ink color, master data for each ink color, and each ink color It is characterized by comprising; and a comparison and calculation means for comparing the 披 inspection data obtaining the print position deviation size for each ink color.

The color conversion means, the master recording means, the master data, the YMCK recording means, and the comparison / calculation means, which are the respective constituent elements of the printing register evaluation apparatus of the fifth aspect, are all the same in the invention of the second aspect. Has the same effect as the name.

Therefore, the print position deviation measured by the print register evaluation apparatus according to the fifth aspect is the data to be inspected obtained by color-separating the color image pickup signal for the target print portion for each ink color as described above. Similarly, prior to that, the master image data obtained by color-separating the appropriate color image pickup signal for the target printing portion for each ink color and stored in the master recording unit are read into the comparison / calculation unit, Here, comparison is made for each ink color, that is, the reference master data and the corresponding ink color data are respectively compared, and printing of the ink color data compared to the master data based on the comparison is performed. The positional deviation dimension can be calculated.

Therefore, in the print inspection apparatus equipped with this print registration evaluation apparatus, for each of a plurality of ink colors forming the target print section, the position of each ink is displaced from the reference print position in what direction. Whether or not it can be automatically determined. As described above, the criterion in this determination does not change with each determination because the angle of view of the color television camera for obtaining the master data and each ink color data is constant.

In order to solve the fourth problem,
The invention apparatus according to claim 6 is a monitoring color television camera, and at least one fixed focus first camera which is used in combination with the color television camera to magnify a defect in a main print area attached to a printed material to be conveyed at a high resolution. It has one lens, one fixed-focus second lens that magnifies and images the noticeable printing portion for printing position deviation detection attached to the printed matter in combination with the color television camera, and a lens exchange mechanism that selects these lenses. A surveillance camera unit and a traverse rail having a length equal to or larger than the entire width of the printed matter and extending in the width direction of the printed matter and supporting the camera unit slidably are provided. A traverse mechanism for moving the camera unit,
The monitoring color television camera, the lens exchange mechanism, and the monitoring control unit for controlling the traverse mechanism are provided.

In a sixth aspect of the invention, the traverse mechanism has a surveillance camera unit supported by the traverse rail, which traverses the printed matter conveyed to the surveillance position along the width direction of the surveillance camera unit. Enables color imaging of printed matter with a color television camera. The monitor control unit controls the traverse mechanism to move the monitor camera unit to a position where the color TV camera can pick up the defect of the printed matter automatically detected, and the color TV camera periodically detects the print position deviation. The traversing movement is performed to a position where the target printing portion of can be imaged. Further, the monitoring control unit controls the lens replacement mechanism of the monitoring camera unit to replace the lens so that the first lens is combined with the color television camera when monitoring a defect, and when monitoring the target printing unit. The lens is exchanged so that the second lens is combined with the color television camera. Further, the monitoring controller controls the image capturing operation of the color television camera to magnify the image of the defect or the printing unit of interest at each traverse position.

Therefore, this monitoring device can pick up the defect of the printed matter which is automatically detected irregularly at regular intervals, can pick up the image of the printing part of interest periodically, and the focusing operation is unnecessary in these image pick-ups. Also, these can be magnified and imaged at magnification ratios adapted to different sizes of the target printing unit.

[0045]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS. In FIG. 1, reference numeral 1 denotes a printing apparatus that performs, for example, gravure rotary printing, which includes first to fourth printing units 2 to 5. These printing units 2-5
Is a plate cylinder 6 and a blanket cylinder 7 rolled on the plate cylinder 6,
The blanket cylinder 7 has an impression cylinder 8 rolled therein, and the printing paper S is passed between the blanket cylinder 7 and the impression cylinder 8 to perform color printing on the printing paper S. .

The printing paper S is the feeder section 1a of the printing apparatus 1.
The paper is fed from the paper feeding device 9 arranged at. By this paper feeding operation, the printing paper S is first passed through the first printing unit 2 and then sequentially passed through the second to fourth printing units 3 to 5,
Paper discharge machine 10 arranged in the delivery section 1b of the printing apparatus 1
It is then discharged to the outside and wound up, for example. Further, the print colors of the printing units 2 to 5 are shared by the first printing unit 2 using K (black) ink and the second printing unit 3 using C (cyan) ink, for example. Share the printing,
The third printing unit 4 shares printing with M (magenta) ink, and the fourth printing unit 5 shares printing with Y (yellow) ink.

A printing plate (not shown) removably wound around the plate cylinder 6 of each of the printing units 2 to 5 prints a printing register mark (see a reference symbol M in FIG. 3) as a notable printing unit for detecting a printing position deviation. This has a marking part for
In this embodiment, the marking portions are provided at both end portions in the width direction apart from the main printing area. The left and right marking portions are provided with a slight shift in the transport direction of the printing paper S in accordance with the positional relationship of the traverse mechanism described later.

Therefore, in this printing apparatus 1,
As shown in FIG. 3, printing register marks M in the shape of, for example, "cross-shaped" are printed on both ends of the printing paper S in the width direction, and a predetermined printing ("A" in FIG. 3) is made in the main printing area between them. (Represented by letters.) Each of the printing units 2 to 5 prints the print register mark M with the respective ink. If there is no print position deviation, the print register mark M is printed at the same position in an overlapping manner. The print register mark M of another color ink, which is printed later, is displaced from the print register mark M of the color printed on the print sheet M in any of the front, rear, left, and right directions.

As shown in FIG. 1, the printing apparatus 1 has printing register sensors 11 to 14 corresponding to the printing units 2 to 5, respectively.
Is provided. These sensors 11 to 14 output a register sensor signal each time the print register mark M is printed on the corresponding printing unit 2 to 5, or each time the mark M is detected.

These sensor signals are supplied to the printing register evaluation device 51, which will be described later, to be used for obtaining position information (Y address) in the transport direction of the printing paper S, and also to the printing controller 15. . The printing press controller 15 controls the entire printing operation of the printing apparatus 1 and the like. Moreover, the controller 15 issues a control command for changing the rotation speed of each impression cylinder 8 when it is necessary to correct the print position deviation based on the signals of the print register sensors 11 to 14 supplied thereto. Therefore, the conveyance speed of the printing paper S is adjusted to reduce the print position deviation between the printing units.

The delivery unit 1b of the printing apparatus 1 is provided with a defect detecting television camera 21 provided in the printing inspection apparatus according to the first embodiment and a monitoring apparatus 24 described later. The print inspection device performs a print in-line inspection on a printed matter printed by the printing device.

The television camera 21 is arranged so as to face the printing surface of the printed matter Sa, with the defect detection position at which the printed sheet (printed matter Sa) on which all the printing has been carried being conveyed as a field of view. Sa is scanned along the width direction orthogonal to the carrying direction. In order to obtain a required resolution and to scan the entire width of the printed matter Sa, the cameras 21 are usually arranged in parallel in the width direction of the printed matter Sa. A one-dimensional CCD image sensor (also called a CCD line image sensor or a CCD linear array image sensor) is adopted as a light receiving portion of the television camera 21. The field of view of the television camera 21 is illuminated by an illumination device (not shown).

The light receiving portion of the camera 21 outputs, for example, a monochrome defect image pickup signal. This defect image pickup signal is supplied to the defect detection device 23 via the gain correction circuit 22,
It is processed by the electronic circuit of the device 23. The gain correction circuit 22 as the normalizing means performs processing for canceling the gain fluctuation of the imaging level and optimizing the level of the imaging signal.

The defect detecting device 23 determines whether the printing performed in the main printing area of the printed matter Sa is good or bad, and this determination makes a defect in the printing surface (represented by B and C in FIG. 3, represented by defect B). Is the ink that has bounced off, and defect C is a print defect.)
The position of a in the width direction is measured.

To this end, the detection device 23 includes, for example, a contour extraction circuit, first and second defect recognition sections, first and second defect determination circuits, and a defect position measurement circuit. . The contour extraction circuit takes in the gain-corrected image pickup signal, emphasizes a change in this signal, and thereby extracts a contour pattern of an image.

The first defect recognition unit is supplied with the contour pattern extracted for the printed matter relating to the non-defective product, and also stores the first contour pattern memory as a master pattern, and the contour extracted for the printed matter to be inspected. A first pattern enlarging circuit for forming a pattern to be inspected in which a pattern is supplied and the contour pattern is enlarged to absorb some errors in conveyance accuracy, and the master pattern and the pattern to be inspected are compared and collated. And a first pattern matching circuit that does. This recognition unit,
When the pattern to be inspected has a defect of chipping property as shown in C in FIG. 4, a part of the master pattern corresponding thereto protrudes from the pattern to be inspected,
That part is recognized as defect information. Then, the first defect judgment circuit to which the defect information thus obtained is supplied judges whether or not the defect information is the set defect.

Similarly, the second defect recognizing unit is supplied with the contour pattern extracted for the printed matter relating to the non-defective product, and enlarges the contour pattern to form a master pattern, and thus is obtained. A second master pattern memory for storing the master pattern and a second pattern matching circuit for supplying the contour pattern extracted for the printed matter to be inspected as an inspected pattern and for comparing and collating this with the master pattern are provided. doing. When the pattern to be inspected has a flying defect as shown by B in FIG. 4, this recognizing unit causes a part of the pattern to be inspected corresponding to the protrusion to the master pattern. , That part is recognized as defect information. The second defect determination circuit supplied with the defect information obtained in this way determines whether the defect information is the set defect.

Then, the output of both recognition sections, that is, the defect position measuring circuit to which the detected defect is supplied measures the position of the printed matter Sa in the width direction for the defect. The defect signal obtained by this measurement is transmitted to the print controller 1
5 and the printing register evaluation device.

In the present invention, the color printed matter Sa
If at least a part of the dot print area constituting the halftone is included and the quality of the print in that area is determined, the following configuration may be adopted as the defect detection device used therefor.

This detecting device includes a CCD color camera for enlarging and picking up an image of an arbitrary point of interest in the dot print area of a printed matter including at least a part of the dot print area, and a color image pickup signal from the CCD color camera for each of the points of interest. A color conversion circuit that discriminates dots for each ink color and a dot size calculation for each ink color discriminated by this circuit are performed on one or more dots to obtain data to be inspected, or the discrimination is performed. An inspected data forming circuit that obtains inspected data by performing an area calculation for each ink color on one or more dots, and a size calculated for the dots for each ink color in the noted point of the reference printed matter. Or, a master memory that stores the area as master data for each ink color, and the master data and the data to be inspected for each ink color A comparator for separately comparing, and a determination circuit for determining whether it is within an acceptable value for the comparison result. Such a defect detection device for halftone printed matter, when the result of the determination is out of the allowable value,
A defect signal is issued assuming that there is an abnormality in the size or density of the determined ink color dot (therefore, the print color tone is different from the predetermined color tone).

The output of the defect position measuring circuit provided in the defect detecting device 23 is supplied to the color still image display device 37. As shown in FIG. 4, the device 37 includes a color still image control circuit 38, an RGB memory 39, and a monitor color television 40 as a monitor color display.

The RGB memory 39 is supplied with a color image pick-up signal from the monitor color television camera 28 described later and normalized by the gain correction circuit 41 through the color still image control circuit 38. The memory 39 stores the RGB color signals of the supplied color image pickup signal. The color still image control circuit 38 is supplied with a defect signal having position information from the defect detection device 23, a register evaluation signal output by a print register evaluation device 51, which will be described later, and a color image pickup signal passed through the gain correction circuit 41. To be done.

This circuit 38 stores color still image information in the RGB memory 39, and also stores the RGB still image information in the RGB memory 3.
The image information for one screen saved in 9 is displayed on the monitor color television 40 as a color still image.
In this still image display, the color still image control circuit 38
When a defect signal is supplied thereto, image information including the defect is displayed on the television 40 as a color still image, and when a register evaluation signal is supplied, image information including the evaluated print register mark M is displayed. A color still image is displayed on the television 40, and at other times, the image information of the print surface taken at an arbitrary XY coordinate position designated as necessary is displayed on the television 40 as a color still image. .

These switchings are controlled by a controller for the entire print inspection apparatus (not shown), and the priority of the switching is the color still image display including the print register mark M is the first and the color still image display including the defect is the second. The last is a color still image display on a random printing surface. The color still image display on the random printing surface is performed according to a program pre-installed in the controller (not shown) or keyboard input. By such various screen displays, the status of print quality, the status of defects, and the status of print position deviation due to the print registration mark can be visually recognized by the operator.

Further, the delivery unit 1b of the printing apparatus 1 has a monitoring device 24 with a defect monitoring position defined on the downstream side of the defect detection position in the conveying direction of the printed material Sa as a visual field.
Is arranged. The surveillance device 24 includes a traverse mechanism 25 and a surveillance camera unit 2 which is moved by the traverse mechanism 25.
6 and the monitor control unit 27.

In the first embodiment, the print register marks M are provided at both ends in the width direction of the printed matter Sa, respectively.
A pair of traverse mechanisms 25 is used corresponding to each. These mechanisms 25, as shown in FIGS. 2 and 3, are used for the traverse rail 2 that is longer than the entire width of the printed material Sa.
5a and a drive unit 25b for moving the surveillance camera unit 26 along the rail 25a.

The traverse rail 25a is arranged so as to face the printing surface at the defect monitoring position so as to cross the width direction of the printed material Sa, and a drive portion 25b is provided at one end of the rail 25a. Due to the operation of the drive unit 25a, the monitoring camera unit 26 slidably supported on the traverse rail 25a in the axial direction thereof moves the printed matter S.
It is moved over the full width of a. The movement of the surveillance camera unit 26 by the drive unit 25a is performed according to the defect signal (position information indicating the width direction position of the defect on the printed material Sa) supplied to the monitoring control unit 27. As a result, the surveillance camera unit 26 is moved and arranged in advance at a position where the detected defect passes.

Then, for example, the one traverse mechanism 25 located on the downstream side in the conveying direction of the printed matter Sa (indicated by the arrow in FIG. 3) shares the print inspection for the left half in the width direction of the printed matter Sa in FIG. Surveillance camera unit 26
And the other traverse mechanism located on the upstream side in the transport direction shares the print inspection with respect to the right half of the printed matter Sa in the width direction and moves the unit 26.

As shown in FIGS. 2 to 4, the surveillance camera unit 26 includes a surveillance color television camera 28 supported by a traverse rail 25a, and the television camera 28.
A lens exchange mechanism 29 connected to, a first lens 30 for defect monitoring attached to the mechanism 29, a second lens 31 for monitoring a register mark attached to the mechanism, and a television camera 28. Strobe light emitting device 32
And

As the monitoring color television camera 28, one having a light receiving portion thereof composed of an area type color CCD image sensor or the like is adopted. The camera 28 converts the light incident on its light receiving portion into an RGB electrical signal according to the light intensity by a photoelectric conversion action, and outputs it as a digital RGB color image pickup signal. The color image pickup signal is subjected to multi-valued A / D conversion processing so that an image is expressed with, for example, 256 gradation levels.

The color television camera 28 is adapted to perform an image pickup operation in accordance with the register sensor signal (a signal representing the position in the longitudinal direction of the printed material Sa). The lens exchange mechanism 29 automatically causes the camera 28 to exchange lenses by selecting and using the first lens 30 or the second lens 31, and a mechanism base that supports the plurality of lenses 30 and 31. For example, the lens 29a is configured to be half-turned horizontally to perform lens selection.

For the first lens 30, for example, a fixed-focus narrow-angle lens capable of obtaining a high resolution of 5 m with an angle of view of 4 mm is used, and the second lens 31 has an angle of view of 4 mm.
A fixed-focus wide-angle lens capable of obtaining a high resolution of 50 m at 0 mm is used. The first lens 30 is not limited to one, and a plurality of first lenses 30 may be provided. In that case, those having different angles of view may be used. The strobe light emitter 32 is for instantaneously illuminating the field of view of the camera 28. In synchronization with this illumination, the camera 28 is
At a high speed of 500,000 seconds, a designated partial area of the printing surface is used as a monitoring field of view, and the area is instantaneously enlarged and imaged. Each of the lenses 30 and 31 is formed by combining a plurality of lens elements and is focused on the printing surface.

As shown in FIG. 4, the monitoring controller 27
It has an image pickup address delay circuit 33, a traverse address control circuit 34, an image pickup control circuit 35, and a lens exchange controller 36.

The image pickup address delay circuit 33 is supplied with a register sensor signal output from the print register sensor 14 for the final printing section 5, in other words, a signal representing the longitudinal position of the printed matter Sa. The delay circuit 33 delays the register sensor signal in accordance with the positional shift of the visual field position of the camera 28 with respect to the print register sensor 14 and performs a delay process for adjusting the signal timing.
The Y coordinate for the surveillance camera unit 26 is obtained, and this Y coordinate is supplied to the imaging control circuit 35.

In the traverse address control circuit 33, a defect signal output from the defect detection device 23, in other words,
Position information representing the widthwise position of the defect in the printed matter Sa is supplied. The control circuit 33 obtains the X coordinate that determines the traverse position of the surveillance camera unit 26 from the supplied defect position information, and this X coordinate is supplied to the imaging control circuit 35.

The image pickup control circuit 35 uses the traverse mechanism 2 so that the surveillance camera unit 26 is arranged at the X coordinate.
In addition to the control of No. 5, the monitoring color television camera 28 is controlled to perform an imaging operation according to the Y coordinate at this coordinate position, and the strobe light emitting device 32 is controlled to emit light at the time of this imaging. . Further, the control circuit 35 controls the lens exchange mechanism 29 so that the defect or the print register mark M can be selectively picked up at the XY coordinates. By this control, the second print is periodically (for example, every time the printed material Sa is conveyed by 100 m).
The lens 31 is selected to perform the printing position deviation monitoring operation, and in other cases, the first lens 30 is selected to perform the defect monitoring operation every time the defect signal is supplied to the traverse address control circuit 34. It has become. The printing position deviation monitoring operation has priority over the defect monitoring operation.

The color image pickup signal passing through the gain correction circuit 41 is supplied to the print register evaluation apparatus 51. This device 51 includes a color conversion circuit 52 as a color conversion unit, a master memory 53 as a master recording unit, a YMCK memory 54 as a YMCK recording unit, and a comparison / operation circuit 55 as a comparison / operation unit. ing.

The color conversion circuit 52 to which the normalized color image pickup signal is supplied in the printing position deviation monitoring operation is a process of separating the received RGB color image pickup signal for each ink color, in other words, each of the printing units 2 described above. Discrimination processing is performed to find out a difference for each ink color used in steps 5 to 5.

Such discrimination is possible by setting a certain conversion condition and converting the RGB color signals in accordance therewith. Therefore, in the first embodiment, the table shown in FIG. 5 is used. Is used. In this table, Y, M, C and K are basic ink colors, W is the ground color of the printing paper S, R, G and B are the three primary colors of light respectively, and the numerical values represent the above-mentioned 256 gradations. . An example of YMCK conversion (ink color separation) in the color conversion circuit 52 according to this table will be described. When the gradation values of each of the R, G, and B3 primary colors are 60 or more, the Y ink is used. It is intended to discriminate that it was printed in.

The ink color data discriminated by the color conversion circuit 52 is supplied to and stored in the master memory 53. This storage is performed for the standard master data. That is,
When the color still image of the print register mark M satisfies the reference condition (it is recognized that there is no print position shift), the color image pickup signal for each ink color discriminated by the color conversion circuit 52 is fetched as master data. It is something to save.

The ink color data discriminated by the color conversion circuit 52 is also supplied to the YMCK memory 54 at the time of inspection and temporarily stored. The YMCK memory 54 stores ink color data separately for each ink color. Therefore, four memories are used for the YMCK memory 54,
Alternatively, one memory is assigned an address for each ink color and divided into four memory areas, and each ink color data is temporarily stored in each memory (or memory area). The temporary storage of the ink color data in the YMCK memory 54 is performed for the print registration mark for which the print position deviation is to be detected. Therefore, the ink color data temporarily stored in the memory 54 is the data to be inspected.

The master data for each ink color stored in the master memory 53 and the inspected data for each ink color temporarily stored in the YMCK memory 54 are supplied in synchronization with each other at the same timing. The comparison / arithmetic circuit 55 has a comparison unit that compares the two data and determines the difference. Further, the circuit 55 has an arithmetic unit for obtaining the print position deviation dimension of the data to be inspected with respect to the master data for each ink color based on the comparison result.

The print position deviation dimension obtained by the processing in the comparison / arithmetic circuit 55 is supplied to the color still image display device 37 as a register evaluation signal and also to the print controller 15. The print controller 15 is configured to perform control for adjusting the print position deviation with respect to the printing unit having the print position deviation based on the register evaluation signal.

A monitoring device 24 having the monitoring color television camera 28 and a print register evaluation device 51 corresponding to the monitoring device 24.
In the first embodiment, a pair of print inspection systems including and are provided, and the first print inspection system among them is responsible for the print inspection of the left half of the printed matter Sa in the width direction. The second print inspection system shares the print inspection for the right half of the printed matter Sa in the width direction.

Next, the print inspection operation by the print inspection apparatus having the above-mentioned configuration will be described. The printing paper S fed from the feeder unit 1a of the printing apparatus 1 is sequentially printed with the respective color inks of K, C, M, and Y by sequentially passing through the first to fourth printing units 2 to 5 to obtain a printed matter Sa. Then, it is conveyed to the delivery section 1b and wound up. In this printing operation, the print register marks M are overprinted on both ends in the width direction of the printing paper S that is out of the main printing area, and the print register sensors 11 to 11 are printed according to the print register marks M for each ink color. 1
In accordance with a control command from the print controller 15 based on the register sensor signal output from the printer 3, the printing apparatus 1 makes an adjustment so that the print position shift does not occur.

However, it is known that it is not possible to expect complete misregistration prevention for a long period of time only by this adjustment, and printing misalignment occurs as printing continues. Such a print position shift is detected and corrected as follows.

First, since the monitor control device 37 first sets the master setting mode at the time of printing the color print to which various adjustments are made, the monitor device 24 is controlled by the image pickup control circuit 35 so that the monitor device 24 can obtain the print registration. The monitoring state of mark M is entered.

That is, the traverse mechanism 25 is operated by the control command of the image pickup control circuit 35, and the position where the monitoring camera unit 26 picks up the print register mark M, in other words, the position shift detection scheduled position where the print register mark passes. As the lens is moved, the lens exchange mechanism 29 is operated via the lens exchange controller 36 according to the control command of the imaging control circuit 35, and the second lens 31 having a wide angle of view is set in the monitoring color television camera 28. The lens is replaced.

Then, in response to the image pickup control command from the image pickup control circuit 35, the timing is adjusted with the arrival of the conveyed printed matter at the defect monitoring position with reference to the sensor signal output from the print register sensor 14 of the final printing unit 5. The area including the print register mark M located at the defect monitoring position when the strobe light emitter 32 emits light is the color television camera 2
The image is magnified and enlarged instantaneously by 8. Since the second lens 31 has a fixed focus in this image pickup, the print registration mark M thereafter is used.
The angle of view does not change in the regular imaging of.

The color image pickup signal of the print register mark M thus picked up is normalized by the gain correction circuit 41 and then supplied to the color still image display device 37 where it is visualized by this device 37. A color still image is displayed on the monitor color television 40. Therefore, the operator can visually check whether or not the print register mark M overprinted with each ink has a print position deviation by visually recognizing the color still image on the monitor color television 40. Then, as a result of the visual check of the color still image on the monitor color television 40, if it satisfies the reference condition that can be evaluated as the master data,
The operator gives an instruction operation to take in the master data.

In the printing register mark M formed by overprinting each ink, the mark M satisfying the reference condition has substantially no color misregistration of each ink. Mark configuration similar to black (Fig. 6)
See). Therefore, the normal print register mark M satisfying the reference condition has a black cross mark configuration in the first embodiment, which is the same as the first print unit 2
It is equivalent to adopting the print register mark M first printed in 1. as a reference.

On the other hand, at the same time when the image is displayed, the color image pickup signal, in other words, the RGB image information is also supplied to the print register evaluation device 51. Therefore, the RGB image information about the overprinted or print register mark M is The color conversion circuit 52 of the printing register evaluation apparatus 51 discriminates each ink color. In other words, which ink color the RGB image information of the print register mark M is made of is classified.

This ink color separation is performed according to the table of FIG. The data for each ink color decomposed in this way is fetched and stored in the master memory 53 as master data for each ink color in accordance with the fetching instruction operation. Since the normal print registration mark M is a black cross mark as described above, the master data is stored in a state where it is apparently not separated for each ink color.

After saving the master data, the printing apparatus 1 shifts to the final printing. During this final printing, the monitoring control unit 27
Is switched to register monitoring mode. As a result, the print registration mark M of the printed matter of the printed matter is also periodically imaged by the camera 28, and the color of the print registration mark M is supplied to the print registration evaluation device 51 to which the color image pickup signal is supplied. The conversion circuit 52 discriminates the color image pickup signal for each ink color to distinguish which ink color the RGB image information of the print register mark M to be inspected is made. The imaged data for each ink color discriminated in this way is used as inspected data, and this inspected data is temporarily stored in the YMCK memory 54 until the next inspected data is supplied.

Next, this inspected data is read from the YMCK memory 54 into the comparison / arithmetic circuit 55. Similarly, in synchronization with it, the comparison / operation circuit 55 has a master memory 53.
Master data is read from. And this comparison
In the arithmetic circuit 55, comparison is made for each ink color, that is, the master data which is the basis of comparison and the corresponding ink color data are respectively compared, and the comparison ink color with respect to the master ink color data is based on the comparison. The shift size of the print position of the data is calculated.
The two-dot chain line in FIG. 6 shows an image in which certain ink color data M ′ is displaced from the master data M, and E and F in FIG. 6 are measured as misalignment dimensions.

The monitoring camera unit 26 used for obtaining the master data and the data to be inspected in the detection of the printing position deviation in the printing inspection apparatus as described above is, as described above, the second lens having the fixed focus. Since the color image is picked up by switching to 31, the judgment criterion in the comparison / arithmetic circuit 55 does not change at each judgment. Then, through this comparison / calculation, for each of the plurality of ink colors on which the print register mark M of the printed matter Sa is printed, in what direction and how much is each ink displaced from the reference print position? That can be automatically determined.

Further, the print register mark M to be inspected has no color misregistration, and although the entire mark is formed as the inspected data of the black cross, the entire mark is in the master memory 53.
Even if the printing position is deviated with respect to the master data stored in, the deviation can be detected and the deviation dimension can be measured as described above. In other words, in the detection of the printing position deviation, if the printing in which the master data is taken is the reference plate, it is known that the printing plate in which the black cross deviates from this plate occurs. be able to.

In addition to the above-mentioned overprinted print register marks, diamond-shaped print register marks are arranged at predetermined intervals along the moving direction or width direction of the printed matter Sa as shown in FIG. It may be installed side by side. Print registration marks MK, MC, MM, M for such array printing
When the print registration deviation is detected in the print registration evaluation measure 51 of FIG. 4 for the printed matter Sa on which Y is printed, the master data is stored in the master memory 53 individually for each ink color. The data to be inspected for each ink color is compared and calculated by the comparison / calculation circuit 55. Therefore, similarly to the inspection of the printed matter having the cross print registration mark, for each of a plurality of ink colors on which the print registration marks MK, MC, MM, and MY are printed, which ink is different from the reference print position? It is possible to automatically determine how much the position is displaced. Note that the two-dot chain line in FIG. 7 indicates the main printing area, and the arrow indicates the transport direction.

As described above, it is possible to judge the quality of the print position deviation for each ink color, and the judgment result is supplied to the print controller 15 as a register evaluation signal (control target value). Therefore, the controller 15 causes the printing apparatus 1 to perform the deviation adjustment for the printing unit, which requires the adjustment of the printing position deviation according to the supplied control target value. Instead of such automatic adjustment of the print position, the control target value is displayed on the monitor color television 40, and based on the visual confirmation, an instruction by a manual operation of the operator is given to the print controller 15 to perform the required printing. You may make it the printing apparatus 1 perform misalignment adjustment with respect to a set.

Moreover, in the print inspection apparatus according to the first embodiment, the inspection of the print position deviation as described above is performed by the monitoring device 24, the color still image display device 37, and the print register evaluation device 51. It is carried out in two printing inspection systems each equipped with. One of the inspection systems inspects the print register mark M attached to one end of the printed matter Sa in the width direction, and the other inspection system inspects the print register mark M attached to the other end of the printed matter Sa in the width direction. inspect. Therefore, it is possible to determine the quality of the print position deviation for each ink color at both widthwise end portions of the printed material Sa.

When the print position deviations at both widthwise end portions of the printed matter are judged to be good or bad, the elongation in the widthwise direction of the rotary printing base paper is different as is often seen in gravure printing, or
When the thickness of each part of the rotary printing base paper on which printing is performed is not uniform and there is a thickness difference in the thickness direction, a misalignment of the printing position occurs on the other end side, or the printed matter is skewed based on the thickness difference. If such occurs, such information can be obtained. Therefore, a measure for avoiding the print position shift and the skew of the printed matter by using the detected monitoring information (when the print position shift and the like can be adjusted, the above-mentioned automatic or manual adjustment cannot be performed, Will stop printing, etc.) can be picked up early.

Further, in the first embodiment,
It is also possible to automatically detect a defect and display the color image as a still image between the inspections of the print position deviation. That is,
In this defect inspection device, a defect detection television camera 21 arranged upstream of the monitoring device 24 scans the printed material Sa conveyed to the defect inspection position in the width direction to obtain defect detection information. Since the image pickup signal of the camera 21 is supplied to the defect detecting device 23, the defect during printing is detected by the processing of the image pickup signal by the detecting device 23, and the quality of the defect is judged. As a result, the defect is recognized. The position of the defect in the width direction of the printed material Sa is measured for the printed material.

Since the mode is switched to the defect monitoring mode in accordance with the detection of the defect, the monitor control unit 27 operates the lens exchange mechanism 29 via the lens exchange controller 36 according to the control command from the image pickup control circuit 35, and the image is displayed. First with narrow corners
The lens is exchanged so that the lens 29 is set on the surveillance color television camera 28. At the same time, the detected defect position information (Y direction coordinate information) is supplied to the traverse address control circuit 34. The image pickup address including the defect is grasped by the image pickup address delay circuit 33 to which the sensor signal (coordinate information in the X direction) of the print register sensor 14 is supplied.

Therefore, the image pickup control circuit 35 operates the traverse mechanism 25 to move the monitoring color television camera 28 with the first lens 30 selected in advance to a position where the defect passes according to the Y coordinate information. Let Next, when the detected defect is conveyed to the field of view of the camera 28 according to the X coordinate information, the imaging control circuit 35 causes the strobe light emitting device 32 to emit light at the same timing and includes the defect. The area is instantaneously enlarged and picked up by the color television camera 28.

Then, the color image pick-up signal from the color television camera camera 28 is sent to the color still image display device 37.
Is supplied to the monitor color television 40 as a color still image. As a result, a color image of the defect is enlarged and displayed on the television 40 with high resolution. The image display of such a defect is performed every time the defect is detected, and the operator can visually recognize the property of the defect on the monitor screen.

As described above, the print inspection apparatus according to the first embodiment regularly has the second lens 3 of the monitoring apparatus 24.
1, the print register mark M is imaged, the color image pickup signal is processed by the print register evaluation device 51 to automatically measure the print position deviation, and the imaged print register mark M is displayed on the color still image display device 37. Color TV 40 for monitors
It can be enlarged and displayed as a color still image.

On the other hand, the defect detection device 23 processes the defect detection information obtained by the defect detection TV camera 21 during the measurement of the printing position deviation, and the defect is automatically detected, and the defect is monitored by the monitoring device. An image is picked up through the first lens 30 of 24, and the image is displayed on the color television 40 for monitoring of the color still image display device 37 as a color still image in a high-resolution enlarged display, and the color of the defect automatically detected by the television 40 is displayed. A still image can be visually recognized.

Therefore, this print inspection apparatus shares the same monitoring device 24 and color still image device 37 so that the automatically detected defect can be visually recognized as a color still image, and the print register mark M can be monitored. Since it is possible to perform the color printing, it is not necessary to separately provide a device for performing the quality determination of the print position deviation and the quality determination of the automatically detected defect in performing color printing, and the quality determination of these can be performed with a small facility burden. It can be carried out.

The present invention is not limited to the first embodiment. For example, the mass data stored in the master memory 53 may be only the mark printed by the first printing unit 2 when the print registration mark is a cross mark. Of course, in this case as well, the overprinted printing register marks are separated into ink colors by the color conversion means, the address is obtained from the register sensor signal, and only the marks printed by the first printing unit 2 are master memory 53. You can capture it in and save it. In this case, it is better that there is a printing position shift, and therefore the reference can be taken in at an early stage when the adjustment image in the printing apparatus 1 is not completed.

Further, in the present invention, the printing portion which is enlarged and imaged to detect the printing position shift is not limited to the printing register mark, and attention is paid to any printing portion having a characteristic in the printing area, and the printing portion to be noticed. May be used.

The present invention can also be implemented by omitting one of the pair of print inspection systems provided in the first embodiment. In this case, the traverse mechanism 25 may move the surveillance camera unit 26 over the entire width of the printed material Sa.

[0112]

The present invention is embodied in the form described in detail above, and has the following effects. According to the print inspection method and apparatus of the first and second aspects of the invention, for each of a plurality of ink colors printed on the print portion of interest of the printed matter, the position of each ink in which direction with respect to the reference print position. It is possible to automatically measure the misalignment dimension as if it is misaligned, and the judgment criterion does not change with each judgment, and it is less affected by the sensitivity of the operator. Judgment can be performed automatically and with high reliability.

According to the printing inspection apparatus of the third aspect of the present invention, the first problem can be solved by the first and second printing inspection systems, and both of these printing inspection systems can be applied to both end portions in the width direction of the printed matter. Since the quality of the print misregistration is determined for each ink color, it is possible to obtain the print misregistration information that is effective in reducing the occurrence of print defects due to the print misregistration, and also to obtain the skew occurrence information of the printed matter. .

According to the print inspection apparatus of the fourth aspect, the same monitoring apparatus and color still image apparatus are shared,
The automatically detected defects can be visually recognized as a color still image, and the size of the print position deviation can be measured based on the monitoring of the target print area such as the print registration mark. Thus, it is not necessary to separately provide a device for performing the quality determination of the print position deviation and the quality determination of the automatically detected defect, and these quality determinations can be performed with a small equipment burden.

According to the print inspection apparatus of the fifth aspect of the present invention, when performing color printing as in the case of the fourth aspect of the present invention, the quality of the print position deviation and the quality of the automatically detected defect are determined. Since it is not necessary to provide a separate device, these quality judgments can be performed with a small facility burden, and the judgment criteria for the quality judgment of the printing position deviation do not change with each judgment, affecting the operator's sensitivity. Since it is less likely to occur, it is possible to automatically and highly reliably determine the quality of the print position deviation.

According to the monitoring device for a print inspection device of the invention of claim 6, it is possible to take an image of a defect of a printed matter which is automatically detected irregularly, and to take an image of a printing portion of interest periodically.
In addition, the focusing operation is not necessary in these image pickups, and the defects and the printing images can be magnified and imaged at magnifications that match the different sizes of the target printing portion. It is suitable for detecting monitoring information for quality judgment.

[Brief description of drawings]

FIG. 1 is a diagram schematically showing a configuration of a print inspection apparatus according to a first embodiment of the present invention, together with a printing apparatus.

FIG. 2 is a diagram showing a configuration of a monitoring device included in the print inspection apparatus according to the first embodiment, together with a printed matter, as viewed from a direction of an arrow ZZ in FIG.

FIG. 3 is a plan view showing the configuration of the monitoring device shown in FIG. 2 together with a printed matter.

FIG. 4 is a block diagram showing a circuit configuration of the print inspection device according to the first embodiment.

FIG. 5 is a diagram showing the contents of a table used as a reference for color separation in a color conversion circuit included in the print inspection apparatus according to the first embodiment.

FIG. 6 is a diagram showing an example of a print register mark detected by the print inspection apparatus according to the first embodiment.

FIG. 7 is a diagram showing another example of a print register mark detected by the print inspection apparatus according to the first embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Printing device, 21 ... Defect detection television camera, 23 ... Defect detection device, 24 ... Monitoring device, 25 ... Traverse mechanism, 26 ... Surveillance camera unit, 27 ... Monitoring control part, 28 ... Surveillance color television camera, 29 ... Lens exchange mechanism, 30 ... First lens, 31 ... Second lens, 37 ... Color still image display device, 40 ... Monitor color television (color display for monitor), 51 ... Print register evaluation device, 52 ... Color conversion circuit (Color conversion means), 53 ... Master memory (master recording means), 54 ... TMCK memory (YMCK recording means), 55 ... Comparison / arithmetic circuit (comparison / arithmetic means).

Claims (6)

[Claims] 1. A color television camera for monitoring, which has a constant angle of view, picks up an image of a print portion of interest for printing position shift detection, which is attached to each of the inks on a printed matter printed in color with a plurality of color inks. Discriminates the color image pickup signal output from each of the ink colors, uses at least the ink color data for the first printed ink as master data, and then uses the camera for the target printing unit to be inspected. The obtained color image pickup signal is discriminated for each ink color to produce inspection data for each ink color, and the inspection data is compared with the master data to obtain the print position deviation dimension for each ink color. A printing inspection method characterized by: 2. A monitoring color television camera for picking up, at a constant angle of view, a target print portion for detecting a print position deviation, which is attached to each of the inks on a printed matter color-printed with a plurality of color inks, and the target print. A color conversion means for discriminating the color image pickup signal of the camera for each ink color for each ink color, a monitor color display for visualizing the color image pickup signal and displaying a still image, and a color stillness of the noted print portion on the display. A master recording unit that captures and saves ink color data for each ink color discriminated by the color conversion unit as master data when the image satisfies a reference condition; and the target printing after the master data is stored. The display data for each ink color obtained by discriminating the color image pick-up signal output from the color television camera which has picked up the image by the color conversion means. A YMCK recording unit that captures and temporarily stores the data, and compares the master data for each ink color and the display inspection data for each ink color to obtain the print position deviation dimension for each ink color. A print inspection device comprising a calculation means. 3. A color television camera for monitoring, a color conversion unit, a master recording unit, a YMCK recording unit, and a comparison / comparison unit.
It is equipped with first and second print inspection systems equipped with arithmetic means,
The color television camera included in the first printing inspection system is arranged at a position where the target printing portion attached to one end in the width direction of the printed matter can be imaged, and the color television included in the second printing inspection system. The print inspection apparatus according to claim 2, wherein a camera is arranged at a position where an image of the target print portion attached to the other widthwise end of the printed matter can be captured. 4. A defect detection position where a printed matter printed by color printing with a plurality of color inks is conveyed is arranged as a visual field.
A defect detection television camera that scans the printed matter conveyed to the defect detection position in the width direction, and a defect image pickup signal supplied from the television camera is processed to determine whether the printed matter is good or bad. When it is determined that there is a defect detection device that measures the position of this defect in the width direction of the printed matter, and the defect monitoring position defined on the downstream side of the defect detection position in the conveyance direction of the printed matter is arranged as a visual field. A monitoring color television camera movably provided in the width direction of the printed matter over the entire width of the printed matter or more,
According to the defect position information supplied from the defect detection device, the surveillance color television camera is moved to a planned position where the defect passes, and when the defect passes the planned position by the camera, the defect is detected. While enlarging and imaging a predetermined area including, periodically moving the monitoring color television camera to a position deviation detection planned position through which a target printing portion for printing position deviation detection attached to the printed matter passes, and by this camera A monitoring device for enlarging and imaging a predetermined area including the target printing part when the target printing part passes the misregistration detection position, and a color image signal from the monitoring color television camera is visualized to monitor as a color still image. And a color still image display device for displaying on a display for color, And a print registration evaluation device for measuring this, wherein the monitoring device is a monitoring color television camera, and at least one fixed-focus first lens which is combined with the camera to image the defect at high resolution, A print inspection apparatus comprising: a second lens having a fixed focus, which is combined with the color television camera to magnify and image the target printing portion; and a lens exchange mechanism for selecting these lenses. 5. A color conversion unit for discriminating a color image pickup signal of the monitoring color television camera for the printing unit of interest for each ink color by the printing register evaluation apparatus, and the attention on the monitoring color display. A master recording unit that captures and saves ink color data for each ink color discriminated by the color conversion unit as master data when the color still image of the printing unit satisfies a reference condition; and saving the master data. YMCK recording means for later capturing and temporarily storing the display inspection data for each ink color obtained by discriminating the color image pickup signal outputted from the color television camera which has picked up the image of the noted printing portion by the color conversion means. The print position deviation dimension for each ink color is obtained by comparing the master data for each ink color and the display data for each ink color. 5. The print inspection apparatus according to claim 4, further comprising: a comparison / calculation unit. 6. A surveillance color television camera, at least one fixed-focus first lens for magnifying at high resolution, in combination with the color television camera, defects in a main print area of a printed material to be conveyed, A monitoring camera unit having one fixed-focus second lens for combining the color television camera and a magnified image of the printing portion for printing position deviation detection attached to the printed matter, and a lens exchange mechanism for selecting these lenses. And a traverse rail having a length equal to or greater than the entire width of the printed matter, extending in the width direction of the printed matter, and slidably supporting the camera unit, and the camera unit along the rail. A traverse mechanism for moving the camera, the color television camera for monitoring, the lens exchange mechanism, and the traverse machine Printing inspection apparatus for monitoring apparatus and a monitoring control unit that controls.