JP2951037B2 - Inspection method and apparatus for printed matter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for inspecting printed matter, and more particularly to a method for judging quality of a printed matter in a sheet-fed printing press, a rotary printing press, a rewinding machine, etc., and informing when a defect occurs. And equipment.

[0002]

2. Description of the Related Art Inspection of print quality during printing differs depending on the type of printing press. In the case of offset sheet-fed printing presses and offset rotary printing presses, the operator removes and visually inspects them.In the case of gravure rotary printing presses, the flash is fired in synchronization with the speed of the printed material and visual inspection is performed. I have. Further, after printing is completed, only the surface inspection of the printed matter is performed by the rewinding machine.

Attempts have been made to shift from such a visual inspection to an automatic inspection. For example, a laser light source scans the printing paper in the width direction and the reflected light is received by a photoelectric conversion device such as a photomultiplier for inspection. Inspection methods using image sensors such as image pickup tubes and CCD sensors have been provided.

[0004] In any case, only a good detection accuracy is obtained at the laboratory stage, and none of them can be put to practical use at the printing site.

For example, in the laser system, the adjustment of the optical system is complicated, and the positional accuracy is required. Therefore, the detection accuracy cannot be maintained in a violent environment near the printing press or in a bad environment with heat. Also, in the image scanner method, when performing full-width inspection of a wide material, an optical path length from an object to be inspected to an imaging unit is required.
The detection unit becomes large-scale. When inspecting printed materials that are flowing further, the accuracy of the transport system affects the detection performance,
In particular, displacements of the object to be inspected such as speed fluctuations in the flow direction, meandering in the width direction, and fluttering in the vertical direction cannot be inspected by these methods.

Accordingly, the applicant of the present invention has provided an inspection apparatus as disclosed in Japanese Patent Application Laid-Open No. 62-11152, which can cope with a positional shift of an inspection object. In this method, a non-defective product in a printed material actually printed is used as a reference printed material, and a pass / fail inspection is performed based on whether or not the printed material to be inspected is different from the reference printed material.

[0007]

According to this inspection method, a product showing a difference within a predetermined range with respect to a reference printed matter is determined as a non-defective product, and it is prevented that a defect is determined even if there is a slight displacement. be able to.

Here, when printing a large number of sheets,
A slight change in color tone and misalignment of the paper occur. In some cases, when compared with the reference printed matter, the printed matter has a difference exceeding a predetermined range due to the positional deviation, and a printed matter that is not particularly defective is determined to be defective.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object of the present invention is to provide a printed matter inspection apparatus capable of inspecting a printed matter running on a printing machine or a rewinding machine without being affected by positional deviation. Aim.

[0010]

According to the present invention, there is provided a light source for uniformly illuminating the surface of a printed material, and a light source having a luminous efficiency characteristic and having a field of view overlapping with each other in a direction perpendicular to a running direction of the printed material. Detecting means for arranging a plurality of light receiving elements arranged to form a signal for each pixel in accordance with the reflected light from the printed matter, extracting pixel data in a state where the pixels overlap each other from the running printed matter; Means for averaging pixel data taken out from a predetermined number of non-defective printed materials to form first reference data, and a first reference data memory for storing the first reference data And a data difference pixel extraction circuit for comparing image data taken out of two consecutive printed materials on a pixel-by-pixel basis to extract pixels having different data, and a data difference pixel extraction circuit An allowable value determining circuit for increasing a pass / fail judgment level for each pixel compared with other pixels, and comparing the inspection data taken out of the inspection target printed matter by the detection means with the contents stored in the first reference data memory. A subtraction circuit for extracting a difference by using the first subtraction circuit and a permissible value determined by the permissible value determination circuit;
A second reference data memory for storing pixel data taken out of the inspection target printed matter as the second reference data when the determination circuit determines that the print is non-defective; and storing the data stored in the second reference data memory in the first reference data memory. It is an object of the present invention to provide a printed matter inspection apparatus having a switching means for giving the subtraction circuit instead of the contents of the reference data memory.

[0011]

With the detection means, pixels for inspecting the printing paper are set so as to overlap each other, and a plurality of non-defective data are first taken in. An average of the plurality of non-defective data is averaged by a first reference data forming means, and is stored as a first reference data in a first reference data memory. Next, two consecutive pieces of data to be inspected are compared with each other by a data difference pixel extraction circuit by the detection means, and pixels having different data are extracted. With respect to the extracted pixels, a pass / fail judgment level larger than the other pixels is determined by the permissible value calculation circuit and stored in the permissible value memory. Using this pass / fail judgment level, the subtraction circuit extracts the difference between the newly-inspected data to be inspected and the storage content of the first reference data memory. This difference is compared with a value stored in an allowable value memory by a determination circuit to make a pass / fail determination.

In the case of a non-defective product, the data to be inspected are sequentially stored as new reference data in a second reference data memory, and are subsequently taken in based on the second reference data provided in place of the first reference data by the switching means. Inspection is performed on the data to be inspected. If the product is defective, the reference data is not updated.

In the inspection, the comparison is performed for each pixel, and then the addition data for the designated area is compared to detect a special defect such as a streak.

[0014]

As described above, according to the present invention, the quality of the subsequent data to be inspected is determined using the first reference data extracted from the average value of the data to be inspected, and the inspected data determined to be non-defective is determined. Since the data is used as the second reference data and the second reference data is sequentially updated as long as it is determined to be non-defective, it is improper even if the data to be inspected taken from the running printed matter has a positional deviation. Since erroneous determination of a non-defective product can be prevented, unnecessary waste of printed matter does not occur.

[0015]

FIG. 2 is an explanatory view showing a state where the inspection apparatus according to the present invention is installed in an offset rotary printing press. The web-shaped printing paper W running on the rotary printing press is continuously printed by each printing unit and discharged. In the case of a web-shaped printed matter, the data to be inspected is detected by the upper body detecting unit 10A and the lower body detecting unit 10B since the upper and lower cylinders print on both the upper and lower surfaces, and the detected data is transmitted to the determining unit via the relay unit. Transmitted. At the same time, the traveling signal of the printed matter is detected by the encoder unit 20, and the detected data to be inspected is transmitted to the determination unit.

FIG. 3 shows a pattern on a printed web, and the first and second sheets are printed continuously. Of course, there are many pictures before and after these two printed pictures, but they are not shown. Looking at these two pictures, the first and second pictures have a different mark portion at the upper left of the original picture portion even if the picture itself has no problem. Therefore, it is necessary to exclude this part from the determination target and determine the quality of only the picture part.

FIG. 4 shows an optical system structure of the signal detecting unit, which is installed in the width direction of the printing paper W as a light source so as to illuminate an inspection area extending in the width direction of the surface of the printing paper W. A single cylindrical fluorescent lamp 11 is provided, and a plurality of photodiodes PD (PD1, PD2, PD3,...) Of channels 1 to n arranged linearly in the width direction of the printing paper W.
PDn), a light source 11 and a photodiode
The light source 11 is positioned at an angle θ with respect to a perpendicular line from the photodiode PD to the surface of the printing paper W, and has a positional relationship in which direct light from the light source 11 does not hit the photodiode PD. , Θ = 45 °. Here the light source 11
It is desirable to use a white light source having a large amount of light and a long life. However, since the signal processing is performed at an extremely high speed, general fluorescent lamps or incandescent lamps whose light amount changes with a commercial power supply of 50/60 Hz cannot be used. It is necessary to use an incandescent lamp or the like that emits light by the DC power supply.
Passing only the reflected light from the inspection area on the surface of the printing paper W,
In order to block light other than the reflected light, for example, direct light from the light source 11, a light-shielding box 12 and a slit 13 are provided, so that the amount of light from the light source 11 can be used effectively, In order to shield light and the like, a reflection plate 14 and a light shielding plate 15 are provided. The reflected light from the inspection area on the surface of the printing paper W passes through the slit 13, is received by the photodiode PD, and is converted into an electric signal corresponding to the amount of received light. As the photodiode PD, one having luminosity characteristics as spectral sensitivity characteristics is used.

FIG. 5 shows a method of scanning a printed material. In the inspection of the printing paper surface using a photo diode as shown in FIG. 4, for example, a width of 1030 mm and a circumference of 625 mm
Of a rotary printing press having a plate cylinder size of 700 [rpm], that is, 7300 [mm / sec], in the printing paper width direction (see FIGS. 4B and 5).
Photodiodes PD (PD1, PD2, ...
As shown in FIG. 4 (B), 69 PDs 45 are linearly arranged, and the inspection surface (field of view, that is, one unit of data detection corresponding to a pixel to be described later) a _ij by one photo diode is obtained. FIG as shown in 5 becomes the inspection surface of 17.5 × 15 mm, the pitch of the light receiving element so as to be adjacent field (e.g., _{a i 1} and _{a i2)} overlap by a distance 2.5 mm 15
mm is determined, and the light-shielding box 12 and the slit 13 are provided. Further, since the printing paper W itself is transported by the printing machine, the surface of the printing paper W is sequentially inspected line by line as shown in FIG. Therefore, in the flow direction Z of the printing paper W, a processing circuit capable of inspecting the surface of the printing paper W line by line at a light receiving element pitch of 10 mm is used, and adjacent visual fields (for example, _ai'2 and _{ai '+ 2} ) are used. Is designed to allow inspection such that 5 mm overlap occurs in the Z direction, and inspects the entire surface of the printing paper W.

Here, the procedure for determining the size of the visual field will be described. In an offset rotary printing press, meandering of the running web, that is, displacement of the web in the printing width direction, and displacement of the printing machine in the web flow direction due to printing speed fluctuation and expansion and contraction of the web occur. Even in paper, the color tone fluctuates.

Therefore, assuming that the apparatus of the present invention is installed in an actual rotary offset printing press, a simulation test of the displacement of the web in the original paper, the color tone fluctuation, and the like was performed. The result was that the effect of positional deviation and color tone fluctuation was large. Therefore, based on the measured displacement data, the size of the field of view is determined so that the density variation in the sensor-field due to the displacement is several percent or less of the sensor output. , 17.5 × 15mm
It was ² of the size of the field of view.

FIG. 5 shows the amount of overlap between the visual fields. This is because when defects such as dripping, oil dripping, and ink dripping occur between the visual fields, only one part of the actual size defect is included in one visual field without overlapping the visual fields. The inspection performance obviously decreases. Therefore, in the device of the present invention,
The device structure is such that the print paper flow direction and the width direction visual field overlap, and the overlapping part of the visual field is about the size of a defect that can be detected in a single large visual field. It was 5 mm. As a result, the entire defect can be detected in each field of view. The surface of the printing paper W is divided into visual fields a _ij (one inspection area by light receiving elements) which are indicated by oblique lines and are inspected. The visual field a _ij and the visual field a _i2 are in the width direction of the printing paper W. The field of view _ai'2 and the field of view _{ai '+ 2} are overlapped by a distance b2 in the direction of the printing paper.
Wrapped, generally, each field overlaps with eight adjacent fields in the paper flow direction and width direction. Also, c1 indicates the light receiving element pitch, and c2 indicates the inspection pitch in the printing paper flow direction Z.

In this inspection using the photodiode, the inspection is performed line by line by timing with a timing pulse from the rotary encoder 20.

FIG. 6 shows the appearance of an embodiment of the present invention, in which the display panel is viewed from the front.
In this display panel, an operation panel is arranged on the right side, and an operation section and a determination section are provided vertically in two stages on the left side.

The operation panel has a liquid crystal display panel LCD arranged on the upper part, a numeric keypad including "NEXT", "ENT" and cursor operation keys on the lower left side, a mode selection switch SW15 and a permissible amount on the lower right side. A setting switch SW14 is provided, and a power switch SWp is provided at the lower right corner of the panel surface. The operation unit is provided with a reference value input display lamp L1 and an inspection display lamp L2, a reference value input switch SW11 and an inspection start / stop switch SW12, and the determination unit is provided with a failure occurrence display lamp L3 and a failure position display lamp L4. , L5, a fault display / output reset switch SW13, and an encoder rotation indicator L6 on the right side of the determination unit.

This apparatus advances the operation while observing the display contents on the operation panel, and the operation procedure is predetermined as the display contents.

FIG. 7 shows only the operation panel portion of the display panel shown in FIG. The liquid crystal display panel LCD can display 13 lines and 20 characters (or 40 half-width characters). While checking this display, the inspection work is advanced by operating the ten key TK, the mode selection switch SW15, and the allowable amount setting switch SW14.

FIGS. 8 to 14 show the display contents of the liquid crystal display panel LCD in the edit mode. FIG.
Indicates the basic menu in the edit mode. The menus are “Printer Data”, “Paper Width Setting”, and “Permissible Value Level Setting”.
Includes “inspection condition setting”. Selection of a menu item is performed by moving the cursor up and down with the cursor operation keys of the ten keys TK and operating the enter key ENT. FIG.
Is a detailed menu of "Printer Data", which is used to input data on the printing press on which the inspection device is to be installed, and includes "Maximum Paper Width", "Maximum Plate Circumference", "Maximum Printing Speed", After selecting the parentheses of "Printer cylinder: Encoder rotation ratio" and "Printer type", use the numeric keypad TK
Enter a numerical value for the last printing press type, and use the cursor for left and right movement to select “Rotary press” or “Sheet-fed press”.
Make a selection. The initial setting is a rotary press. To operate a sheet-fed press, operate the “→” key. FIG. 10 shows a case where a paper width value frequently used in a target printing machine is input in advance, and five types of paper widths A to E are entered on the numeric keypad TK.
And confirm with ENT key operation.

FIGS. 11 and 12 show the setting of the pixel judgment allowable value level and the addition judgment allowable value level. There are two types of allowable values, a specified value and an arbitrary value, and the specified values are set in advance. No operation is required because a product is used.
First, the cursor in FIG.
To any of the parentheses. Then, the user operates the ENT key to alternately display the specified value and the arbitrary value. Next, when the “→” key is operated, the screen of FIG. 12 appears. On this screen, a character display indicating whether the allowable value level is a specified value or an arbitrary value, a pixel or an addition, and designation by coordinates where the horizontal axis is the density of the reference data and the vertical axis is the allowable level A curve connecting the points is displayed. 3 in these coordinates
By specifying the points a, b, and c, a desired allowable range can be set.

FIG. 13 shows the contents of the condition setting performed at the end of the edit mode. The minimum print speed at the start of inspection and the minimum number of prints at the start of inspection are set by operating the ten keys TK and the ENT key. The next paper edge inspection is a designation of whether or not to inspect the paper edge, and is switched on and off each time the “→” key is operated.

14 to 16 relate to the inspection mode. First, the paper width A already input according to FIG.
Selection of any of E to E or setting of an arbitrary paper width is performed by operating the “↑”, “↓” and ENT keys. With this setting, the display before the inspection is performed as shown in FIG.
Next, when the speed of the printing press and the number of printed sheets reach the inspection start condition, the inspection is performed. When a defective product occurs, a defective display is performed as shown in FIG.

FIG. 17 relates to a check mode. One of menu items is selected by "↑" and "↓", and the check item is confirmed by operating the ENT key.

FIG. 18 shows a state in which the sensor level is displayed off-line separately from the above-described modes, and the detection data of a printing plate in the case of a rotary press is displayed. In a rotary press, a two-stage display is used, but in a sheet-fed press, only an upper stage is displayed. With this display operation, the detection data of the detection unit can be checked.

FIGS. 19 to 21 correspond to FIGS.
Shows the contents of the operation of the device indicated by.
The apparatus is started by the start, and the paper width of the printing press data is input and set in step S1 as shown in FIG.
In step S2, an allowable value level is input and set.
In step S3, the mode is set to the reference value input mode. Subsequently, in step S4, a predetermined number of sheets are added, and in step S5, an average is calculated by calculating an average. The calculated first reference data is stored in step S6.

Thereafter, the first image data and the second image data are read and stored in the memory. By comparing these data, pixels having different data are extracted. Then, an allowable value setting calculation is performed in step S10. The set permissible value obtained by the calculation is stored in the permissible value memory in step S11.

Next, inspection is started in step S21. For this purpose, inspection data is input in step S22. In step S23, the inspection data is compared with the first reference data. If the inspection data is defective, the defect determination process is immediately performed in step S36. If it is a good product, step S24
Stores the inspection data in the second reference data memory as the second reference value. Then, in step S25, the next inspection data is input, and in step S26, it is compared with the second reference data to determine pass / fail. If defective, step S36
The inspection data is input to the second reference data memory in step S27 if it is a non-defective product. Next, inspection data is input in step S30, and the next step S3
In the case of 1, the quality is judged again by comparing with the second reference data again. If the product is defective, the defective product determination process is performed in step S36. If the product is non-defective, the inspection data is stored as new second reference data in step S32.

The inspection operation is repeated, and the inspection of the inspection data is performed using the second reference data until the second reference data is updated a predetermined number of times in step S33. When the predetermined number of times has been reached, the inspection data is input in step S34, and in step S35, the pass / fail judgment is made by comparing with the first reference data instead of the second reference data. The pass / fail judgment is performed on the basis of the first reference data one by one for some of the inspection data.

The second reference is provided for the purpose of updating the reference value so that the inspection object can be inspected without misjudgment due to the positional deviation even if the inspection object has a meandering or positional deviation in the running direction. This is because it is effective to make a comparison with the initial first reference data in order to prevent the detection from becoming undetectable when the density gradually changes.

The comparison with the first reference data is performed by setting the allowable value to the second reference data.
The value is set to be larger than when compared with the reference data.

FIG. 1 shows the internal circuit configuration of the printed matter inspection apparatus described with reference to FIGS.
This circuit includes the photodiode PD described with reference to FIG.
Detection signal and the rotary encoder 2 shown in FIG.
The inspection operation is performed using the generated pulse of 0. In the photodiode PD of FIG. 1, PDs not shown in FIG.
Are added to detect fluctuations in the amount of light.

A light quantity signal corresponding to the print pattern of the printed matter detected by the photodiodes PD1 to PDn is supplied to a light quantity signal processing circuit having a multiplexer 201, a light quantity correction circuit 202, a sample hold circuit 203 and an A / D conversion circuit 204. Can be The light amount signal processing circuit is sequentially switched by the multiplexer 201 and provided to the light amount correction circuit 202. After being corrected for the light amount fluctuation corresponding to the detected light amount of the photodiode PDs, the light amount signal processing circuit is provided to the sample and hold circuit 203, where the peak value is obtained. The digital output corresponding to the peak light amount is taken out to the A / D conversion circuit 204, and is taken out to the switch SW1.

In the light quantity signal correction circuit, a pulse signal from the rotary encoder 20 is given to a phase detection circuit 301, and the multiplexer switching timing generation circuit 302, the sample hold timing generation circuit 303, and the A / D Conversion timing generation circuit 304 produces an output. At this time, the phase detection circuit 3
01 is output from the operation control circuit 401 in the multiplexer 201 and is compared with a command value stored in the internal latch.
3 is used for the timing control of the peak value detection operation and the conversion operation of the A / D conversion circuit 204. The pulse signal from the rotary encoder 20 is also supplied to an inspection start speed confirmation circuit 501, which is used to determine whether the printing speed of the printing press has reached a predetermined value, and is also supplied to an inspection timing generation circuit 502. Inspection start speed confirmation circuit 50
When a confirmation signal indicating that the predetermined printing speed has been reached from 1 is issued, it is used to generate operation timing signals for various circuits described below.

The switch SW1 switches between taking in a digital output from the light quantity signal processing circuit as a reference input or treating it as an inspection input in accordance with a control signal from the operation control circuit 401.

When taking in as a reference input, the switch SW1 is switched to the A side and a digital output is given to the switch SW2. The switch SW2 switches which of A and B should be supplied with a signal in accordance with the timing signal from the inspection timing generation circuit 502. If the printed matter is an odd-numbered picture, it is switched to A side, and if it is an even-numbered picture, it is switched to B side.
If the number is an odd number, the average value calculation circuit 601 determines whether the light amount signal from the switch SW2 and the inspection timing generation circuit 5
The average density of each pixel of the printed matter is appropriately calculated according to the timing signal from 02 and output to the memory 602. The same operation is performed even if the switch SW2 is switched to the B side at the even number, and the average value calculation circuit 603 calculates the average density and outputs it to the memory 604.

The outputs of these memories 602 and 604 are supplied to a data difference pixel extraction circuit 605 and an average value circuit 6.
06. The data difference pixel extraction circuit 605
A permissible value calculation circuit 607 for extracting a pattern called an image portion and a portion called a non-image portion between the patterns and forming a signal for making the allowable value different between the image portion and the non-image portion.
To give output. This is the case when the blanket cylinder is a double cylinder, that is, when the circumference of the blanket cylinder is two times the circumference of the plate cylinder.
In the case of double, two pictures are transferred to the blanket cylinder, but the two pictures are not exactly the same but are partially different, so different tolerances are set for this different part. It is. Average value circuit 6
In step 06, the average density of the image portions of the odd-numbered and even-numbered sheets is calculated and output to the first reference data memory 608. The permissible value calculation circuit 607 calculates permissible values for the image portion and the non-image portion with respect to the reference value from the first reference value memory 608 based on the instruction from the permissible value setting circuit 504 and outputs the permissible value to the permissible value memory 609. give. The setting of the permissible value is performed on a pixel-by-pixel basis so that the inspection performance does not differ between a pixel having a high print density and a pixel having a low print density. The first reference allowable value memory 609 stores an output of the allowable value calculating circuit 607 so as to correspond to a print surface area determined by a mask signal from the mask setting circuit 610. The value stored in the allowable value memory 609 is given to the determination circuit 704 via the switch SW4, and is used as an allowable value in a later inspection.

From the first reference allowable value, a predetermined value indicating circuit 6
13 is subtracted by a subtraction circuit 611 from a predetermined value given by
These allowable values, which are obtained and stored in the second reference allowable value memory 612, are determined according to the reference data.
Is switched using. The comparison with the first reference data is an intermittent inspection for every predetermined number of sheets, and is mainly for the purpose of inspecting a large change in density, so that the allowable value is increased.

Next, the switch SW1 is set to B to perform the inspection.
When switching to the side, the digital signal from the light amount signal processing circuit is supplied to the second reference data memory 701 and the detection value adding circuit 802. Second reference data memory 70
1 stores the digital signal from the switch SW1 when the timing signal from the inspection timing generation circuit 502 is given. When the non-defective product output is given from the judgment circuit 704, the stored value is output to the second reference data memory 702 and stored as a reference value. The second reference value of the second reference value memory 702 is stored in the switch SW
3 is used by switching to the reference value of the first reference data memory 608. The switch SW3 switches to the A side at the print rising stage in response to a signal from the inspection number counting circuit 503 based on the output of the inspection timing generation circuit 502, and supplies the stored value of the first reference data memory 608 to the pixel data subtraction circuit 703. Then, after the print rising stage, the mode is switched to the B side, and the value stored in the second reference data memory 702 is given to the pixel data subtraction circuit 703. The output of the pixel data subtraction circuit 703 is provided to the determination circuit 704, and the pass / fail determination is performed according to the relation of the inspection data to the first or second reference data, and the determination result is output. The non-defective product output is stored in the second reference data memory n7.
01 and (n-1) 702, and the second reference data is sequentially updated with new non-defective inspection data.
Based on the updated second reference data, the quality of the printed matter is determined for each pixel. The judgment result is displayed on the display control circuit 40.
2, the set value determination result is displayed on the display 403, and is also supplied to the failure determination output contact 901 and the panel failure determination display LED 902.

In this inspection apparatus, in addition to the quality judgment on a pixel-by-pixel basis, quality judgment on a designated area is also performed. The designated area refers to, for example, an area for detecting a streak-like print defect, and handles data of the area designated by the designated area designating circuit 801. The designated area designating circuit 801 designates, as a fixed value, the area around the plate cylinder in the flow direction of the printed matter, for example, with one pixel in FIGS. 4 and 5 as one unit.
As the reference data, the output added by the designated area addition circuit 802 from the storage data of the first reference data memory 608 is given to the designated area addition value reference data memory 804 and stored, and the storage value is subtracted by the addition data subtraction. Circuit 805 and addition allowable value calculation circuit 806. On the other hand, the inspection data is stored in the designated area detection value addition circuit 803.
Is given to the addition data subtraction circuit 805, the difference from the value of the command area addition value reference memory 804 is obtained, and the difference is given to the judgment circuit 808. The addition allowable value calculation circuit 806 calculates an addition allowable value from the reference value of the designated area addition value reference memory 804 according to the set value of the allowable value setting circuit 504, and gives the result to the addition allowable value memory 807. The addition allowable value memory 807 is also supplied with a mask signal from a mask setting circuit 809 for performing a mask setting according to the set value of the paper width setting circuit 505. The mask signal and the addition allowable value from the addition allowable value calculation circuit 806 are also stored. Is stored in accordance with. Additive memory 8
The stored value of 07 is given to the determination circuit 808, and the quality of the specified area is determined. The determination result is given to the display control circuit 402, and the set value determination result is displayed on the display 40.
3 and is given to a failure determination output contact 901 and a panel failure determination display LED 902.

Each of the above-described circuit elements generates a control signal in accordance with a control signal from the operation control circuit 401. The inspection start speed confirmation circuit 501, the allowable value setting circuit 504, and the paper width setting circuit 505 are provided by the operation control circuit 401. Is given. The operation control circuit 401 includes a power switch SW
p, reference input switch SW11, inspection start / stop command switch SW12, failure display reset switch SW13, allowable value setting command switch SW14, mode setting switch S
W15 and the numeric keypad TK are connected to supply necessary signals to each circuit element. Necessary signals include a signal given to the inspection start speed confirmation circuit 501 at the time of mode switching, an allowable value setting circuit 504, and a paper width setting circuit 505.
And a signal for instructing a content for changing the setting or the content of the instruction.

In FIG. 1, the sensor level check circuit 506 displays the detection level of each photodiode PD on the display 403 in a bar graph or the like.

A reference input contact S indicated by a dashed line
W11 ', an inspection start / stop input contact SW12', and a failure display reset input contact SW13 'are equivalent to a reference input switch, an inspection start / stop switch, and a failure reset switch for the operation control circuit 401. The inspection interruption input contact SW16 is for stopping the inspection operation at the time of splicing.

Although these inspection devices can perform their functions satisfactorily by themselves, they can be connected to peripheral devices and transmit / receive data to realize a system and realize quality assurance and stabilization of the quality of the entire process. An application example is shown below.

First, as data used in the printing process, specification data of a printing item is sent from the management computer 220 of the host to the printing press availability meter 221. The printing press operation rate meter 221 and the inspection data presetting device 22
5 and picks up data necessary for the inspection device from the item specification data, and transfers the data to the printed material inspection device 23.
Send to 4. The printed matter inspection apparatus 224 sets inspection conditions based on this data and can automatically perform the inspection. Conversely, it is also possible to send the finalized data when the set value is changed from the inspection device to the inspection data preset device 225 so as to always have the latest data.

Next, when the inspection device detects a defective portion of the printed matter, the inspection device outputs a defect signal, and the timing control device 226 activates a marker, an instruction labeler, and a jector based on the signal to detect a defective position. Can be notified to an operator or the like, and a failure signal is output to a failure monitor (defective image storage and display) 233 and displayed as an image. It will be easier.

Further, by connecting the inspection apparatus and the printer 227, it is possible to create a quality card such as the content, position, and quantity of a defect, and to easily search later.

Further, by sending a failure signal to the printing press operation rate meter, the management of the number of non-defective products becomes easy.

The inspection apparatus can automatically start and stop the inspection by receiving the operation signal splicing signal and the rotation speed signal from the printing press 222, and can eliminate the switch operation by the operator. Erroneous operation due to mistake is eliminated.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention.

FIG. 2 is a diagram showing a state where the present invention is applied to a rotary press.

FIG. 3 is a diagram showing a method of handling a non-image area of a printed matter according to the present invention.

FIG. 4 is a diagram illustrating a configuration of an optical system of a signal detection unit according to an embodiment of the present invention.

FIG. 5 is a diagram showing a method of scanning a printed material according to the present invention.

FIG. 6 is a diagram showing an external configuration of an embodiment of the present invention.

FIG. 7 is a diagram showing only an operation panel portion in the display panel shown in FIG. 6;

FIG. 8 is a view showing display contents of a liquid crystal display panel LCD in an edit mode.

FIG. 9 is a view showing display contents of a liquid crystal display panel LCD in an edit mode.

FIG. 10 is a view showing display contents of a liquid crystal display panel LCD in an edit mode.

FIG. 11 is a view showing display contents of a liquid crystal display panel LCD in an edit mode.

FIG. 12 is a view showing display contents of a liquid crystal display panel LCD in an edit mode.

FIG. 13 is a view showing display contents of a liquid crystal display panel LCD in an edit mode.

FIG. 14 is a view showing display contents of a liquid crystal display panel LCD in an inspection mode.

FIG. 15 is a diagram showing display contents of a liquid crystal display panel LCD in an inspection mode.

FIG. 16 is a diagram showing display contents of a liquid crystal display panel LCD in an inspection mode.

FIG. 17 shows a liquid crystal display panel LC in a check mode.
The figure which shows the display content of D.

FIG. 18 is a diagram showing display contents of a liquid crystal display panel LCD displaying a sensor level offline.

FIG. 19 is a flowchart illustrating the operation of the device according to the present invention.

FIG. 20 is a flowchart illustrating the operation of the device according to the present invention.

FIG. 21 is a flowchart illustrating an operation of the device according to the present invention.

FIG. 22 is a diagram showing an entire system according to the present invention.

[Explanation of symbols]

 10A Upper Body Detector 10B Lower Body Detector 11 Light Source 12 Shield Box 13 Slit 14 Reflector 15 Shield 20 Encoder 301 Phase Detector 302 Multiplexer Switching Timing Generator 303 Sample & Hold Timing Generator 304 A / D Conversion Timing generation circuit 401 Operation control circuit 403 Set value judgment result display 501 Inspection start speed confirmation circuit 502 Inspection timing generation circuit 504 Allowable value setting circuit 505 Paper width setting circuit 506 Sensor level check circuit 601 Average value calculation circuit 602 Odd number average value memory 603 Average value calculation circuit 604 Even number average value memory 605 Data difference pixel extraction circuit 607 Permissible value calculation circuit 608 First reference data memory 609 First reference permissible value memory 610 Mask setting circuit 61 Subtraction circuit 612 Second reference allowable value memory 613 Predetermined value indication circuit 701 Second reference data memory n 702 Second reference data memory (n-1) 703 Pixel data subtraction circuit 704 Judgment circuit 801 Designated area indication circuit 802 Designated area addition circuit 803 Detection value addition circuit 804 Designated area addition value reference memory 805 Addition data subtraction circuit 807 Addition allowable value memory 808 Judgment circuit 809 Mask setting circuit PD Photodiode L lamp L4 Faulty position display lamp L5 Faulty position display lamp SW11 Reference value input switch SW12 Inspection start / stop switch SW13 Fault display / output reset switch SW14 Allowable amount setting switch SW15 Mode selection switch SWp Power switch LCD Liquid crystal display panel

Claims (5)

(57) [Claims] 1. A light source for uniformly illuminating the surface of a printed material, and each light source having a luminous efficiency characteristic and arranged in such a manner that the visual fields overlap each other in a direction perpendicular to a running direction of the printed material, and each pixel is arranged in accordance with light reflected from the printed material. Detecting means having a plurality of light receiving elements for forming signals and extracting pixel data in a state where pixels overlap each other from a running printed matter, and pixel data extracted from a predetermined number of non-defective printed matters by the detecting means. First reference data forming means for forming a first reference data by averaging the first reference data, and a first reference data storing the first reference data.
A data memory, a data difference pixel extraction circuit for comparing image data taken out of two consecutive printed materials on a pixel-by-pixel basis and extracting pixels having different data, and a pass / fail judgment level for the pixels extracted by the data difference pixel extraction circuit. A permissible value determining circuit for making the pixel larger than the other pixels; and a subtracting circuit for comparing the inspection data extracted from the inspection target printed matter by the detection means with the contents stored in the first reference data memory to extract a difference. And a determination circuit that compares the output of the subtraction circuit with the allowable value of the allowable value determination circuit to determine the acceptability.
A second reference data memory for storing pixel data taken out of the inspection target printed matter as the second reference data when the determination circuit determines that the print is non-defective; and storing the data stored in the second reference data memory in the first reference data memory. An inspection apparatus for printed matter, comprising: switching means for giving the subtraction circuit instead of the contents of the reference data memory. 2. A print area of a printed material according to claim 1, wherein a paper width setting circuit for setting a width of paper to be printed by a printing machine, and an allowable value by said allowable value determining circuit in accordance with a set value of said paper width setting circuit. And a mask circuit for providing a signal for determining a printed matter. 3. A counting circuit for counting the number of inspections of a printed matter according to claim 1, wherein said switching means is switched based on an output of said counting circuit to replace said first reference data memory with said first reference data memory. An inspection apparatus for printed matter, wherein the contents of a reference data memory are supplied to the subtraction circuit. 4. A detection value adding circuit according to claim 1, wherein a sum of a predetermined number of pixels on the same straight line along the running direction of the printed matter in the inspection data is obtained, and a reference value from the first reference data memory is provided. A reference value adding circuit for calculating the sum of a predetermined number of pixels on the same straight line along the running direction of the printed matter in the data; a reference adding value memory for storing an output of the reference value adding circuit; A subtraction circuit for calculating a difference between the output of the reference addition value memory and a storage value of the reference addition value memory; an operation circuit for calculating an allowable addition value based on the storage value of the reference addition value memory; An inspection apparatus for printed matter, comprising: an allowable value memory; and a determination circuit for comparing the storage value of the addition allowable value memory with the output of the subtraction circuit to determine acceptability. 5. A paper width setting circuit for setting a width of paper to be printed by a printing press, and an addition allowable value by said arithmetic circuit according to a set value of said paper width setting circuit in a print area of a printed material. A printed matter inspection apparatus having a mask circuit for providing a signal for corresponding determination.