JPS60125545A - Printed matter checking system - Google Patents

Abstract

PURPOSE:To decide defectives quickly with a high precision by positioning and detecting printed matters to be checked which are placed on a conveyor and picking up a graphic or the like with a high density resolution on a basis of detection signals and comparing and calculating them with a reference graphic pattern. CONSTITUTION:Printed matters 2 to be checked are sucked up with a vacuum paper sucking device 3 one by one from the top and are introduced onto a belt conveyor 4, and the printed matter 2 is positioned by a horizontal pad plate 12 of a positioning means. It is detected by a leading sensor 30, and the pattern or the like of the printed matter is resolved with a high density and is picked up by a camera 28. Each picked-up graphic is compared and calculated with the reference graphic pattern preliminarily stored in a memory, and the printed matter is carried to a paper gathering part 23 of a regular route if it is good, but it is ejected to an unnecessary paper receiver 26 by a gate means 25 if it is defective. Thus, printed matters are decided to be good or not qucicly with a high precision, and defectives are separated and removed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a printed matter inspection system for inspecting the quality of printed matter.

Printing machines print the same print content on many sheets of paper one after another, but after this printing is finished, there are some sheets with unclear prints and blank sheets with no printing at all. If this book is subjected to bookbinding or the like as it is, it will impair its marketability as a book, which is undesirable. In particular, when it comes to important and large volumes of bound books that are to be shipped, those with unclear printing or blank pages as described above are considered to lack marketability, so we may take back the printed materials or books. This placed a heavy financial burden on the suppliers. In addition, it was a great time and financial burden to travel to customers in remote locations for product inspection.

For this reason, methods of visually checking the finished state of printed matter are widely used today. However, this requires skill, and inspection accuracy tends to vary from person to person.
When the amount is large, there is a problem of significant fatigue. In particular, in today's world where printed matter can be produced in large quantities at high speeds, the visual inspection described above has become a serious drawback in terms of improving product productivity.

The present invention has been made by focusing on these conventional problems, and allows a large number of printed materials to be run at high speed in a system that monitors the finished state of the printed material, and to check the quality of the printed material with high precision. In order to make a quick decision,
It is an object of the present invention to provide a printed matter inspection system that can separate and remove printed matter in poor condition as necessary.

In order to achieve this purpose, each printed matter placed on a belt conveyor by a paper feeding means is positioned by a positioning means, and the head of each positioned printed matter is detected by a cue detection means. Based on the detection signal, a camera captures a high-density decomposition of the figures, etc. on the printed matter, and a calculation means compares each imaged pattern with a reference figure pattern stored in memory in advance. When it is determined that the two patterns are different based on the above, the printed matter being sent on the belt conveyor is guided by a gate means to a route different from the regular route. It is.

Embodiments of the present invention will be specifically described below with reference to the drawings.

Fig. 1 and Fig. 2 are a front view and a plan view of an apparatus embodying a printed matter inspection system.

In the figure, (1) is the frame of the main body of the device assembled with an iron frame, etc. On the right side of this frame (1) is a storage space for a large number of printed materials (2). The printed material (2) is placed on a loading platform that moves up and down within the space. Also, on the frame (1) facing the top of the printed matter (2), there is a vacuum paper suction device (
3) is provided with a paper suction pipe (3a) that sucks up the printed matter (2) one by one from above and transfers it to the next belt conveyor (4).
It is designed to be introduced above.

This belt conveyor (4) has a pair of wheels (5) horizontally arranged on the top of the frame (1), and these wheels (
5) A plurality of endless belts (6) stretched between them, a guide roller (7) in contact with the belt (6) on one side of the wheel (5), and a diagram that drives the wheel (5). The belt (6), which is made up of a motor or the like that does not move, is moved by the rotation of a wheel (5), and the printed matter held between the belt (6) and a guide roller (7) is moved.

Furthermore, a pair of wheels (9) are disposed on the upper part of the frame (11) at a predetermined angle offset from the wheel (5), and the wheels (9) have a predetermined angle with respect to the running direction of the belt (6). A side belt (10) running with a corner shifted to the side of the frame (1) is stretched, and these belts are also driven by a motor (not shown) to form a side belt conveyor. This horizontal belt conveyor (formerly) is located on the side of the frame (1), which is the side edge of the printed matter carried along with the belt conveyor (4). Iyu 11QI br Story/
Move it like a field. If you do this, the printed matter (2
) can be reliably positioned laterally, and the finished state of the same portion of each printed matter (2) can be monitored.

03) is a vacuum belt conveyor installed adjacent to the belt conveyor (4), which includes a pair of wheel circles, a plurality of belts (161) having holes (151) stretched over the wheels (04), and this belt (04). 16) and a guide member α81 having a vacuum introduction path 07) for introducing vacuum pressure into the inside.This guide member 0
8) The structure of the tooth is shown in Figure 3. This belt 06) runs in the same direction as the belt 6).

The vacuum belt conveyor 03) accepts the printed matter positioned and sent as described above from the belt conveyor (4), and transfers it to the belt α6) by vacuum pressure.
It works so that it is conveyed in close contact with the

09) is a drum provided adjacent to the downstream end of the bell 10 of the vacuum belt conveyor α3), which is connected to a drive unit (not shown), over which the printed matter passes in the same direction as above.

(20J Hat' A sheet discharge belt conveyor adjacent to the ram α9, consisting of a pair of wheels c21) and a belt 4 stretched between these wheels, the wheel (21) is connected to a drive unit (not shown), and one wheel (21) part includes a frame (1
) is provided with a paper collection section (c) provided at the left end.

(24) is a diagonal belt conveyor installed adjacent to the drum brocade, one end of which is in slight contact with the drum (191),
are rotating in the same direction.

(251 is a vacuum belt conveyor (13+ is an arc-shaped gate plate that is a gate means provided in an undulating manner near the end,
If the output of the camera, which will be described later, shows that the print quality is poor, the printer may protrude into the path of the printed material and transfer the printed material to the drum (+
9) and the belt conveyor 041, and lead out to the waste paper receptacle (26). The inside of this gate plate is driven by a solenoid (25A) via a link (25α).

(271 is a camera box attached to the top of the frame (1) facing the vacuum belt conveyor (l), and inside this camera box Qη is an image sensing camera such as a video camera (281) and a fluorescent lamp etc. Light source (2
91 is accommodated. Please note that this camera box (
27) is long in the direction perpendicular to the traveling direction of the belt α6), and the camera (281) is long in the direction perpendicular to the traveling direction of the belt α6).
The image is taken while scanning the printed image (or characters) above.

Reference numeral 30 denotes a cue sensor which is a cue detection means for detecting the head of the printed matter (2) installed on the right side of the camera box (271), and uses electrical, mechanical, electrostatic or magnetic detection means. The beginning sensor GOI detects the beginning of the paper material and outputs a signal that determines the timing at which scanning by the camera (28) starts and ends.

(31) is a one-sheet feed sensor that outputs a signal every time a printed material is fed, and (32 is a timing for time-division scanning by the camera (28) after the signal is output from the cue sensor (29) (after a set time). This is an encoder that sets image data at each timing and inputs image data to the arithmetic unit.

c33) is a motor installed at the bottom of the frame (1)-, which connects the wheel f51041 and the drum (191,
It is used to drive wheel hubs, etc., and 04) is a vacuum blower, which is used to drive the intake pipe (3) and guide member (18).
It is used to introduce vacuum pressure into the positive vacuum introduction path (17).

In addition, on the front of the frame (1), there is a keyboard C351 for manually inputting external conditions such as the paper size, thickness or feed speed of the printed matter (2), and the measurement range and accuracy of the pattern.
, a turning board θG) equipped with a power switch and a display section, a computer C37) having an input/output of memory data such as a floppy disk, and an arithmetic device for calculating and determining the quality of printed matter. 08) is a 5-row CRT display that displays various control displays.

Figure 4 is a block connection diagram of the print inspection system.

01) is the single sheet feed sensor that detects that the printed matter (2) is fed one by one on the belt conveyor (4), and detects that two or more printed matter (2) are fed at the same time. For example, a system (not shown) is activated to remove all but one sheet from the belt conveyor (4). The above-mentioned head positioning sensor (support) detects the head of the printed matter conveyed by the belt conveyor (4), and upon this detection, a pulse is generated from the pulse generator in the arithmetic circuit.
After counting a predetermined number of pulses (for example, 30 pulses), the positioning and imaging of the camera (to) is started. Furthermore, the timing, speed, and number of images are determined by the pulses, and can be manually entered into the arithmetic device in advance.

(41) is an arithmetic unit of the computer 0η, to which is connected a memory +421, a camera (28+), and an input device (43) for inputting data on print size, feed speed, image resolution accuracy, and pattern. Among these, Memory (42
1 stores in advance a highly accurate complete image pattern that serves as a reference for comparison calculations. For example, a vacuum belt conveyor (131) runs under a camera (281), and the imaged pattern by this camera is transferred to a calculation device (281). 41).

This arithmetic device (4)) outputs each image pattern of the inspection print imaged by the power camera and the reference standard in the memory (421) according to instruction input data such as the size of the print material in the human-powered device (431). The image patterns are compared, and if even one of these corresponding patterns does not match, a signal indicating the mismatch, such as rlJ or signal (6), is output, and a drive device such as a solenoid (25h) is activated. It is activated to drive the gate plate (C), and the printed matter (2) determined to be inconsistent is separated and discharged along the gate plate (C) to the waste paper receiver (261) outside the system. By using the print inspection system, we can collect only those with good print quality and use them for bookbinding.

Next, this printed matter inspection system will be described in more detail along with the operations of the snowmaking parts shown in Figures 1 and 2.

First, among the printed materials to be inspected, find one that is perfectly printed and can be used as a standard printed material that meets the inspection standards even when visually checked, and place it on top of the stack of many printed materials (2). and place them on the paper feed section of the frame (11).

Here, the print inspection device is operated normally, and the paper suction pipe (3) of the vacuum paper suction device sucks up the reference print, and the paper between the belt (6) of the belt conveyor (4) and the guide roller (force The reference printed material is conveyed to the vacuum belt conveyor (13) by the belt (6). During this time, the reference printed matter is also on the side support belt a and receives a biasing force, and the side edge of this is placed on the side support plate (12+). The lateral position is determined by lightly pressing the

The head of the reference printed matter thus positioned is detected by the cue sensor ■, and the camera box (
It passes through the lower part of 2η. During this passage, a predetermined time (very short time) after the cue sensor (30) detects the cue
After that, imaging by the camera in the camera hook is repeated in the scanning direction. In this way, this camera (to) separates the reference printed matter into, for example, 4000 image patterns and captures the images, and each pattern data is stored in the memory (421) of the arithmetic unit. The printed matter is sent to the paper collecting section via the drum α9 and the paper discharge belt conveyor ■.

Next, the printed matter (2) other than the reference printed matter is sucked up one by one by the paper suction pipe (3) and moved on the belt (6) in the same manner as described above. Then, after the beginning of the printed matter reaches the beginning sensor (to), the camera (to) takes an image of the decomposed pattern in the printed state after the same predetermined time as above, and the image of the decomposed pattern in the printed state is taken for each decomposed pattern. A computing device compares each corresponding pattern of the reference printed material with the image (by light intensity detection, etc.), and when the memorized reference pattern matches the pattern of the inspected printed material (2), the computing device outputs a "0" signal. The solenoid (25A) is kept in a de-energized state, and the gate plate 4 is kept in a prone state. For this reason, the printed matter that has been imaged (2)
is guided onto the drum a9 and the belt (2z) above the paper ejection belt conveyor, and further falls onto the paper collection section (c).

In this way, the quality of the printed matter (2) is determined one after another, and only good quality products can be stacked in the paper collecting section.

On the other hand, after a printed material with poor print quality is detected by the above-mentioned cue sensor (a), a similar camera (a)
If a part of the decomposition pattern obtained by the assessment using 281 is determined to be different from the above reference pattern, “1
" signal is output, which causes the above solenoid (25
An energizing current is passed through A) and the gate (29) is erected via the tag link (25α).

Therefore, the printed matter (2) after passing through the camera box (27) is turned downward by the gate (251) and is held between the drum (191 and the belt conveyor (241) and placed on the waste paper tray (26). is discharged and accumulated.

In addition, while each of the printed matter (2) is passing under the camera box 0η, it is necessary to take a high-precision image of the same part as the reference printed matter at the same timing. It is necessary to maintain high precision.In other words, it is necessary to prevent the printed matter (2) from swinging or curling up in this position.In order to prevent this, in this embodiment, the paper printed matter (2) is By vacuum pressure (negative pressure) introduced into the eye hole (151) on the aO,
It is designed to be fed in close contact with this belt (161).

As described above, according to this embodiment, it is possible to detect not only blank paper or torn paper but also the adhesion of dust on the image, discoloration due to this dust, misregistration, and even color shift, which are usually problems that result in poor print quality. It is possible to automatically detect everything and separate printed matter into good and bad parts.

Although not shown in the drawing, a sensor for detecting the color difference between the printing color of the printed matter and the paper is also provided, and it is possible to arbitrarily discharge non-conforming printed matter based on the above calculation result. can.

As described above, according to the present invention, the image pattern of the reference printed matter stored in the memory in advance and the highly resolved image pattern of the inspected printed material are input to the arithmetic unit based on the instruction conditions inputted by the input device. By employing a system that performs comparison calculations in the process, it is possible to determine the quality of printed products and to classify them at high speed and with high precision.

In this way, well-printed products can be distributed as-is as products, or they can be bound and shipped, eliminating the need to collect printed materials after shipping, and eliminating the financial burden on suppliers.

[Brief explanation of drawings]

Figure 1 is a front view showing a specific device in the printed matter inspection system of the present invention, Figure 2 is a plan view, and Figure 13 is a sectional view taken along line 1-1I of Figure 2, and Figure 4 is the printed matter inspection system. FIG. (3) Paper feeding means, (4) Fist... Belt conveyor, l
... positioning means, (29... gate means, (to)
...Camera, ■...Cutting detection means, (4I)...
・Arithmetic device, (4) memory, (4) life input device. Representative patent attorney Izumi Ohno

Claims (2)

[Claims] (1) The printed matter to be inspected placed one by one on the belt conveyor by the paper feeding means is positioned by the positioning means, the head of the positioned printed matter is detected by the cue detection means, and the detection signal of the detection means is detected. Based on this, a camera decomposes and images the figures, etc. on the printed matter with high density, and each imaged pattern is compared with a reference figure pattern stored in a memory in advance in an arithmetic unit,
When it is determined that the two patterns are different based on the calculation result, the printed material to be inspected is discharged in a direction different from the regular route by means of a gate means. Inspection system. (2) The comparison operation in the arithmetic device is based on the instruction data π from the input device.
The printed matter inspection system described in section.