JP4011966B2 - Printing position inspection method and apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention belongs to the technical field of inspecting the relative positions of printing and processing on paper such as forms and emails.
[0002]
[Prior art]
When printing the same pattern (fixed information), image the positional relationship between the feature points of the printed pattern (for example, position indication marks) and the feature points on the pre-formed paper (for example, processing traces such as feed holes) A technique for making a determination based on an image is known. Further, when printing many different patterns (variable information), if the margin information exists on the paper and the position display mark to be printed on the margin portion can be included in the variable information, the positional relationship is determined by the same technique. be able to.
[0003]
[Problems to be solved by the invention]
However, when the position display mark does not exist independently in a sufficiently wide margin portion, that is, when not only the position display mark but other other marks are adjacent to each other, the position display mark or It is difficult to specify the corresponding feature point (processing trace) on the paper in the captured image. In particular, when different contents (variable information) are printed depending on the page, and other marks are also variable information, it becomes more difficult. Under such circumstances, there is no conventional technique that can be used with high reliability.
[0004]
The present invention has been made to solve such a problem, and the purpose thereof is not only when the position display mark but other marks are adjacent to each other and the other marks are variable information. Even so, it is an object of the present invention to provide a printing position inspection method and apparatus that can obtain high reliability and can be used practically.
[0005]
[Means for Solving the Problems]
The above problems are solved by the present invention described below. That is, in the printing position inspection method according to claim 1 of the present invention, the position indication mark and the other indication mark other than that are printed in an arrangement in the transfer direction, and the position indication mark on the paper having the processed trace is present. A printing position inspection method for inspecting a relative position with respect to the processing trace, wherein a mark detection process of detecting a leading position of the other mark or the position display mark and outputting a trigger signal, and inputting the trigger signal Then, an imaging process of imaging the other mark and the position display mark and outputting an imaging signal, an A / D conversion of the imaging signal and A / D conversion to generate a captured image, and the other mark in the captured image determine included in a predetermined region 3 or included in a predetermined region 1, and the processing trace and the position indication mark in a predetermined region 2 when it is included in the region 1 Calculating a pair positions are those as consisting of process of calculating the relative position between the machining trace and the position indication mark in a predetermined region 4 when contained in the region 3.
[0006]
According to the present invention, in the mark detection process, the start position of another mark or position display mark is detected and a trigger signal is output, and in the imaging process, the trigger signal is input and the other mark and the position display mark are imaged and imaged. In the processing process, the captured image signal is input and A / D converted to generate a captured image, and whether another mark is included in the predetermined region 1 or the predetermined region 3 in the captured image is determined. When it is included in the region 1, the relative position between the position display mark and the processing trace is calculated in the predetermined region 2, and when included in the region 3, the relative position between the position display mark and the processing trace is calculated in the predetermined region 4. The correct position is calculated. In other words, even if the detection in the mark detection process is unstable, if any head position of another mark or position display mark is detected, the position display is performed in a predetermined area corresponding to each of the captured images triggered by the detected position. A relative position between the mark and the processing trace is calculated. Therefore, not only the position display mark but also other marks are adjacent to each other, and even when the other mark is variable information, a printing position inspection method that can obtain high reliability and can be provided is provided. .
[0007]
According to a second aspect of the present invention, there is provided the printing position inspection apparatus according to the second aspect of the present invention, wherein the position indication mark and other marks are printed in an arrangement in the transport direction, and the position indication mark on the paper having a processed trace is present, A printing position inspection apparatus for inspecting a relative position with respect to a processing trace, comprising a mark detection means, an imaging means, and a processing means, wherein the mark detection means is a head position of the other mark or the position display mark. , And outputs a trigger signal. The imaging means inputs the trigger signal, images the other mark and the position display mark, outputs an imaging signal, and the processing means outputs the imaging signal. input a / D converter to generate a captured image, to determine whether the other mark is included in a predetermined region 3 or included in a predetermined region 1 in the captured image, is included in the region 1 In this case, the relative position between the position display mark and the machining trace is calculated in the predetermined area 2, and when included in the area 3, the relative position between the position display mark and the machining trace is calculated in the predetermined area 4. The correct position is calculated.
[0008]
According to the present invention, the mark detection means detects the start position of another mark or the position display mark and outputs a trigger signal, and the image pickup means receives the trigger signal and images the other mark and the position display mark. A signal is output, and the image pickup signal is input and A / D converted by the processing means to generate a picked-up image, and it is determined whether another mark is included in the predetermined region 1 or the predetermined region 3 in the picked-up image. When it is included in the region 1, the relative position between the position display mark and the processing trace is calculated in the predetermined region 2, and when included in the region 3, the relative position between the position display mark and the processing trace is calculated in the predetermined region 4. The correct position is calculated. In other words, even if the detection by the mark detection means is unstable, when the head position of either another mark or position display mark is detected, the position display is performed in a predetermined area corresponding to each of the captured images triggered by the detected position. A relative position between the mark and the processing trace is calculated. Therefore, not only the position display mark but also other marks are adjacent to each other, and even if the other mark is variable information, a high-reliability print position inspection apparatus that can be obtained and used is provided. .
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described. An example of the configuration of the printing position inspection apparatus of the present invention is shown in FIG. In FIG. 1, 1 is a camera, 2 is an optical sensor, 3 is a data processing unit, 4 is a PLL, 5 is a warning light, 6 is an alarm, and 100 is paper (web).
The camera 1 is an imaging means for capturing a captured image by capturing an area (mark area) where a position display mark and other marks are printed on the paper 100. As the camera 1, an area sensor camera or a line sensor camera having an image sensor such as a CCD (charge coupled device) type or a MOS (metal oxide semiconductor) type and an imaging optical system (lens), a driving / amplifying circuit, etc. Can be used. When the line sensor camera is used, a two-dimensional image is picked up by the main scanning and the sub-scanning by transferring the printed material 100.
[0010]
The photoelectric sensor 2 is a sensor for detecting a characteristic part (pattern outline, mark, etc.) of the paper 100 to be transferred. The detection signal of the photoelectric sensor 2 gives the timing of imaging by the camera 1. That is, the photoelectric sensor 2 detects the leading position of another mark or position display mark and outputs a trigger signal (details will be described later).
[0011]
The data processing unit 3 controls the operation in the printing position inspection apparatus, processes for extracting printing position marks and processing traces, processes for calculating those positions, and processes for determining the quality of the paper 100 from the calculated relative positions. , Etc. (details will be described later). The data processing unit 3 can be realized by hardware and software of a data processing device such as a personal computer or an image processing device.
[0012]
A programmable logic controller (PLC) 4 is a programmable sequence controller with a built-in microcomputer. The PLC 4 performs a process such as operating the warning lamp 5 and the alarm buzzer 6 by comprehensively determining whether or not there is a character blur defect output from each of the data processing units 3a, 3b,. .
[0013]
The warning lamp 5 is a warning lamp for informing the operator by lighting the lamp when it is determined by the PLC 4 that the printed matter 100 is defective.
The alarm buzzer 6 is an alarm buzzer for emitting an alarm sound to notify an operator when the printed material 100 is determined to be defective by the PLC 4. The operator can grasp the situation and take necessary measures when the warning light comes into eyes and the warning sound enters the ear.
[0014]
In the above configuration, the operation of the printing position inspection apparatus of the present invention will be described with reference to FIGS. FIG. 2 is a flowchart showing an operation process in the printing position inspection apparatus of the present invention. FIG. 3 is a diagram showing a position indication mark on the paper 100 and a feed hole which is a processing trace. FIG. 4 is a diagram illustrating the arrangement of the detection points of the photoelectric sensor 2, the paper 100, the regions 1 to 4, and the like in the imaging region (field of view) of the camera 1. FIG. 5 is a diagram showing a captured image when the photoelectric sensor 2 detects the head of the type mark. FIG. 6 is a diagram showing a captured image when the photoelectric sensor 2 detects the head of the position display mark.
[0015]
First, as a specific example for explaining the operation, a position display mark, another mark, and a processing trace on the sheet 100 to be inspected will be described with reference to FIG. FIG. 3 shows pages 107 to 110 of the paper 100. Each page has a position display mark 11, a type mark 12, a page mark 13, and a feed hole 14. In contrast to the position display mark 11, the type mark 12 and the page mark 13 are other marks.
The position display mark 11 is a mark indicating the position of a number of different pictures (variable information), and is a rectangular mark positioned at the beginning of nine rectangular marks arranged in a line as shown in FIG.
[0016]
The type mark 12 is a mark indicating the type of many different patterns (variable information), for example, the type of cover, contents, retrofitting, etc. As shown in FIG. The type is indicated by the number.
The page mark 13 is a mark indicating a page in binary, and as shown in FIG. 3, the page mark 13 is a rectangular mark located in the second to eighth of nine rectangular marks arranged in a line. The second to eighth rectangular marks indicate the eighth to first digits in the binary number. The black rectangle represents 1 and the white rectangle represents 0.
[0017]
The feed hole 14 is a processing trace that has been processed to transfer the paper 100 by the pin tractor. As shown in FIG. 3, the feed holes 14 are a series of circular holes formed at equal intervals in the transport direction on both sides of the paper 100.
This feed hole 14 is formed in the processing step of the paper 100. Further, the position display mark 11, the type mark 12, and the page mark 13 are printed as variable information in the subsequent printing process. Therefore, the relative positions of the two fluctuate, and whether or not they are included in the allowable range is inspected by the position inspection apparatus of the present invention.
[0018]
An operation process in the printing position inspection apparatus of the present invention will be described with reference to a flowchart shown in FIG.
First, in step S1 (mark head detection) in FIG. 2, the photoelectric sensor 2 detects the head position of the type mark 12 or the position display mark 11 printed on the paper 100 to be transferred and outputs a trigger signal.
Next, in step S <b> 2 (mark imaging), the data processing unit 3 inputs the trigger signal and outputs an imaging command to the camera 1. The camera 1 captures an image at that timing and outputs an image signal.
[0019]
Next, in step S3 (captured image generation), the data processing unit 3 inputs the captured image signal of the camera 1, performs A / D (analog-to-digital) conversion, generates a captured image, and stores it in the memory. The camera 1 is arranged in the transfer path of the paper 100 so that the detection point of the photoelectric sensor 2 and the paper 100 are arranged as shown in FIG. Further, the photoelectric sensor 2 is arranged in the transfer path of the paper 100 so that the detection point and the imaging region (field of view) of the camera 1 are arranged as shown in FIG.
[0020]
The imaging region (field of view) and the captured image have a correspondence relationship. Therefore, the captured image obtained by using the trigger signal as the timing as described above is an image including the position display mark 11 and the feed hole 14 as shown in FIGS. As described above, FIG. 5 is a diagram showing a captured image when the photoelectric sensor 2 detects the top of the type mark 12. FIG. 6 is a diagram showing a captured image when the photoelectric sensor 2 detects the head of the position display mark. Whether the photoelectric sensor 2 detects the top of the type mark 12 or the top of the position display mark 11 cannot be predicted in the type mark 12 composed of line segments as shown as an example. That is, the type mark 12 is individual information and has several types of marks having different shapes, and the detection point may or may not include a line segment due to misalignment in printing or transfer.
[0021]
Regions 1, 2, 3, and 4 are shown in the imaging region (field of view) of the camera 1 shown in FIGS. 4 to 5. These areas 1 to 4 are imaging areas (fields of view), that is, predetermined areas set in advance for the captured image. Among these areas, the area 1 is an area where the type mark 12 exists in the captured image when the photoelectric sensor 2 detects the head of the position display mark 11. When the type mark 12 exists in the area 1, there is no type mark in the area 3. Region 3 is a region where the type mark 12 exists in the captured image when the photoelectric sensor 2 detects the head of the type mark 12. When the type mark 12 exists in the area 3, the type mark 12 does not exist in the area 1. When such a captured image is generated in step S3, the process proceeds to step S4.
[0022]
Next, in step S4 (other mark position?), The data processing unit 3 determines whether the type mark (other mark) 12 exists in the area 1 or the area 3. When the type mark 12 is present in the area 1, the position indication mark 11 and the feed hole 14 are present in the area 2. At that time, the process proceeds to step S5. When the type mark 12 exists in the area 3, the position display mark 11 and the feed hole 14 exist in the area 4. At that time, the process proceeds to step S6.
[0023]
Next, in step S5 (extracting the mark of area 2), the data processing unit 3 extracts the position display mark 11 and the feed hole 14 existing in the area 2. Then, the process proceeds to step S7.
Further, in step S <b> 6 (extracting the mark of area 4), the data processing unit 3 extracts the position display mark 11 and the feed hole 14 existing in the area 4. Then, the process proceeds to step S7.
[0024]
Next, in step S7 (position calculation), the data processing unit 3 calculates the positions (X11, Y11) and (X14, Y14) of the extracted position display mark 11 and the feed hole 14. The position is calculated as, for example, a barycentric coordinate.
[0025]
Next, in step S8 (good / bad determination output), the data processing unit 3 calculates a relative position (X11−X14, Y11−Y14) = (ΔX, ΔY) from each position, and the relative position ( It is determined whether or not ΔX ≦ Δp and ΔY ≦ Yp within the allowable range (ΔX, ΔY), and a determination result is output.
[0026]
The operation has been described above. Although the case of single color printing has been described above, the case where the paper 100 is multicolor printed will be described with reference to FIG. Also in the case of multicolor printing shown in FIG. 7, the photoelectric sensor detects the head of the type mark or the head of the position display mark of the first color as described above. Imaging is performed by the camera at the detection timing. The imaging region (field of view) at that time includes a first color position display mark, a second color position display mark, and a target feed hole for calculating a relative position corresponding to each. FIG. 7 shows an example of the case of two-color printing, but it is easy to apply to the case of multiple colors of three or more colors from FIG. 7 and the description thereof.
[0027]
FIG. 7A shows an area 24 including a position indication mark for the second color and a corresponding feed hole when the photoelectric sensor detects the head of the type mark, that is, when the type 3 is included in the area 3. Yes.
FIG. 7B shows an area including the position display mark of the second color and the corresponding feed hole when the photoelectric sensor detects the head of the position display mark of the first color, that is, when the type mark is included in the area 1. 22 is shown.
FIG. 7C shows a region 14 including a position indication mark of the first color and a corresponding feed hole when the photoelectric sensor detects the top of the type mark, that is, when the type 3 is included in the region 3. Yes.
FIG. 7B shows an area including the position display mark of the first color and the corresponding feed hole when the photoelectric sensor detects the head of the position display mark of the first color, that is, when the type mark is included in the area 1. 12 is shown.
[0028]
In summary, when the photoelectric sensor detects the head of the type mark, the print position of the first color is inspected in the area 14 and the print position of the second color is inspected in the area 24. In the case of multiple colors, an area 34 for inspecting the print position of the third color, an area 44 for inspecting the print position of the fourth color, etc. may be set.
On the other hand, when the photoelectric sensor detects the head of the position display mark for the first color, the print position of the first color is inspected in the area 12 and the print position of the second color is inspected in the area 22. In the case of multiple colors, an area 32 for inspecting the print position of the third color, an area 42 for inspecting the print position of the fourth color, and the like may be set.
[0029]
【The invention's effect】
According to the first aspect of the present invention, not only the position display mark but also other marks other than the mark are adjacent to each other, and even when the other mark is variable information, high reliability can be obtained and practically used. A printing position inspection method is provided.
According to the second aspect of the present invention, not only the position display mark but also other marks are adjacent to each other, and even when the other marks are variable information, high reliability can be obtained. A practical printing position inspection apparatus is provided.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating an example of a configuration in a printing position inspection apparatus of the present invention.
FIG. 2 is a diagram illustrating an example of an arrangement of a moving body and a line sensor camera when imaging the moving body.
FIG. 3 is a diagram illustrating a position indication mark and a feed hole that is a processing trace on a sheet.
FIG. 4 is a diagram illustrating an arrangement of detection points of a photoelectric sensor, paper, regions 1 to 4 and the like in an imaging region (field of view) of a camera.
FIG. 5 is a diagram illustrating a captured image when the photoelectric sensor 2 detects the top of a type mark.
FIG. 6 is a diagram illustrating a captured image when the photoelectric sensor detects the beginning of a position display mark.
FIG. 7 is a diagram illustrating a state where a sheet is printed in multiple colors and there are as many position display marks as the number of colors.
[Explanation of symbols]
1 Camera 2 Optical Sensor 3 Data Processing Unit 4 PLL
5 Warning light 6 Alarm 100 Paper (web)

Claims (2)

A printing position inspection method for inspecting a relative position between the position indication mark and the processing trace on a sheet on which a position indication mark and other marks other than the mark are printed in the transfer direction and a processed trace is present Because
A mark detection process for detecting a leading position of the other mark or the position display mark and outputting a trigger signal; inputting the trigger signal to image the other mark and the position display mark; and outputting an image pickup signal Imaging process;
The imaging signal is input and A / D converted to generate a captured image, and it is determined whether the other mark is included in the predetermined region 1 or the predetermined region 3 in the captured image. When included, the relative position between the position display mark and the processing trace is calculated in the predetermined area 2, and when included in the area 3, the relative position between the position display mark and the processing trace is calculated in the predetermined area 4. The process of calculating the correct position,
A printing position inspection method comprising: Print position inspection apparatus for inspecting the relative positions of the position display mark and the processing trace on a sheet on which a position display mark and other marks other than the above are printed in the transport direction and the processed trace is present The mark detection means includes a mark detection means, an imaging means, and a processing means, wherein the mark detection means detects a head position of the other mark or the position display mark and outputs a trigger signal. The trigger signal is input and the other mark and the position display mark are imaged and an imaging signal is output. The processing means inputs the imaging signal and performs A / D conversion to generate a captured image. determines whether other marks are included in a predetermined region 3 or included in a predetermined region 1 in the captured image, the position indication mark in a predetermined region 2 when it is included in the region 1 It calculates a relative position between the machining traces, calculates a relative position between the machining trace and the position indication mark in a predetermined region 4 when contained in the region 3,
A printing position inspection apparatus characterized by that.

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