JPH0461773B2 - - Google Patents

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 the 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 shipping important and large volumes of bound books, those with unclear printing or blank pages as described above are considered to lack marketability, so we do not take back the printed materials or books. This placed a heavy financial burden on suppliers. Additionally, it was a great time and financial burden to travel to customers in remote locations to inspect products.

For this reason, methods of visually checking the finished state of printed matter are widely used today. However, in this case, skill is required, the accuracy of inspection tends to vary from person to person, and when the amount of inspection is large, the problem is that it becomes extremely tiring. In particular, in today's world where printed matter can be produced in large quantities at high speeds, the above-mentioned visual inspection has become a serious drawback in 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. To provide a printed matter inspection system capable of quickly making a judgment and separating and removing printed matter in poor condition as necessary.

In order to achieve the above object, the configuration of the present invention is to
a sheet feeding means for sucking up sheets one by one and delivering them onto a belt conveyor; a horizontal support plate provided on one side of the frame so as to stand up parallel to the belt conveyor; and a single sheet feed sensor provided above the belt conveyor; a horizontal support belt conveyor that is provided diagonally with respect to the traveling direction of the belt conveyor and that supports the printed matter together with the belt conveyor and abuts the horizontal support plate; A vacuum belt conveyor that transports the printed matter on the conveyor while adsorbing it; a discharge belt conveyor and a paper collection section provided on the frame; and a gate means provided in a freely undulating manner between the vacuum belt conveyor and the discharge belt conveyor. , a diagonal belt conveyor provided below and adjacent to the gate means; a camera disposed on the vacuum belt conveyor to take pictures while scanning the printed matter; and a cue detection means for determining the timing at which the printed matter is scanned by the camera. The printed matter to be inspected placed one by one on a belt conveyor by a paper feeding means is positioned by a horizontal support belt and a horizontal support plate, and the head of this positioned printed matter is detected by a cue detection means. Based on the detection signal of this detection means, the camera decomposes and images the figures on the printed matter in high density, and each imaged pattern is combined with a reference figure pattern stored in memory in advance and an arithmetic unit. When it is determined that the two patterns are different based on the result of the calculation, the printed matter to be inspected is transferred to an oblique belt conveyor in a direction different from the discharge belt by means of a gate means. It is characterized by being designed to be discharged.

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

1 and 2 are a front view and a plan view of an apparatus embodying a printed matter inspection system. In the figure, reference numeral 1 denotes a frame of the main body of the apparatus assembled with an iron frame or the like, and a storage space for a large number of printed materials 2 is provided on the right side of this frame 1, and a loader that moves up and down within this storage space is provided. The above printed matter 2 is placed on the stand
is placed. Further, a paper suction pipe 3a of a vacuum type paper suction device 3 serving as a paper feeding means is provided on the frame 1 facing the top of the printed matter 2.
It is arranged so that the sheets are sucked up one by one from the top and introduced onto the next belt conveyor 4.

This belt conveyor 4 has a pair of wheels 5 arranged horizontally on the upper part of the frame 1, and a plurality of endless belts 6 stretched between these wheels 5.
, a guide roller 7 that contacts the belt 6 on one side of the wheel 5, and a motor (not shown) that drives the wheel 5. Move the printed matter held between the two.

Further, a pair of wheels 9 are arranged on the upper part of the frame 1 and are shifted by a predetermined angle from the wheels 5,
A side belt 10 is stretched over the wheel 9 and runs at a predetermined angle to the side of the frame 1 with respect to the running direction of the belt 6. These belts are also driven by a motor (not shown) to convey the side belt conveyor. It consists of 11. This horizontal support belt conveyor 11 moves the side edge of the printed matter carried along with the belt conveyor 4 so that it can be lightly pressed against a horizontal support plate 12, which is a positioning means, and stands up on the side of the frame 1. In this way, the lateral positioning of the printed matter 2 is ensured, and the finished state of the same portion of each printed matter 2 can be monitored.

13 is a vacuum belt conveyor installed adjacent to the belt conveyor 4, and a pair of wheels 14
, a plurality of belts 16 having suction holes 15 stretched over the wheels 14, and a guide member 18 that supports the belts 16 and has a vacuum introduction path 17 for introducing vacuum pressure into the inside. The structure of this guide member 18 is shown in FIG. This belt 16 runs in the same direction as the belt 6 described above.

The vacuum belt conveyor 13 receives the printed matter positioned and sent from the belt conveyor 4 as described above, and acts to convey it in close contact with the belt 16 by vacuum pressure.

Reference numeral 19 denotes a drum provided adjacent to the downstream end of the belt 16 of the vacuum belt conveyor 13, which is connected to a drive section (not shown), over which the printed matter passes in the same direction as above.

Reference numeral 20 denotes a paper discharge belt conveyor adjacent to the drum 19, which consists of a pair of wheels 21 and a belt 22 stretched between them. A paper collecting section 23 is provided at the left end of the sheet.

Reference numeral 24 denotes a diagonal belt conveyor provided adjacent to the drum 19, one end of which is in slight contact with the drum 19 and rotates in the same direction.

Reference numeral 25 denotes an arcuate gate plate, which is a gate means and is provided in an undulating manner near the end of the vacuum belt conveyor 13, and when it is determined by the monitor output of a camera (described later) that the print quality is poor, the gate plate 25 protrudes into the path of the printed material and prevents the printed material from being removed. It is inserted between the drum 19 and the belt conveyor 24 and delivered to the waste paper receiver 26. In addition,
This gate plate 25 meets a link 25a and is driven by a solenoid 25b.

A camera box 27 is attached to the top of the frame 1 so as to face the vacuum belt conveyor 13, and the camera box 27 houses an image sensing camera 28 such as a video camera and a light source 29 such as a fluorescent lamp. has been done. The camera box 27 is long in a direction perpendicular to the traveling direction of the belt 16, and the camera 28 scans and images the printed image (or characters) on the belt 16 in the perpendicular direction.

Reference numeral 30 denotes a cueing sensor which is a cueing detection means for detecting the head of the printed matter 2 installed on the right side of the camera box 27, and electrical, mechanical, electrostatic or magnetic detection means are used. This cue sensor 30
Detects the beginning of paper printing and outputs a signal that determines the scanning start timing and end point of the camera 28.

Reference numeral 31 indicates a single-sheet feed sensor that outputs a signal each time a print is fed, and 32 sets the timing for time-division scanning by the camera 28 after the output of the signal from the cue sensor 30 (after a set time). This is an encoder that inputs image data at each timing to a calculation device.

33 is a motor installed at the bottom of the frame 1, and is used to drive the wheels 5, 14, drum 19, wheel 20, etc.; 34 is a vacuum blower, which drives the intake pipe 3 and the guide member 18;
It is used to introduce vacuum pressure into the vacuum introduction path 17 of the vacuum pump.

Further, on the front side of the frame 1, a keyboard 35 for inputting external conditions such as the paper size and thickness of the printed matter 2, the feed speed, the measurement range and accuracy of the pattern, and an operation panel 36 equipped with a power switch and a display section are provided. A computer 37 is provided which has an arithmetic device for inputting and outputting memory data such as a floppy disk, and for calculating and determining the quality of printed matter. 38 is a CRT display that displays various controls.

FIG. 4 is a block connection diagram of the print inspection system. 31, the printed matter 2 is transferred to the belt conveyor 4
The single sheet feeding sensor detects that two or more printed materials 2 are fed at the same time, and for example, leaves one sheet and excludes the others from the belt conveyor 4. Activate the system (not shown). The head sensor 30 detects the head of the printed matter conveyed by the belt conveyor 4. Upon this detection, a pulse generator in the arithmetic circuit generates a pulse, and a predetermined number of pulses ( For example, 30 pulses) After counting, the above camera 3
8 position and imaging is started. Further, the timing, speed, and number of images are determined by the pulses, and can be input into the arithmetic device in advance.

Reference numeral 41 denotes an arithmetic unit of the computer 37, to which is connected a memory 42, a camera 28, and an input device 43 for inputting data on print size, feed speed, image resolution accuracy, and pattern. Among these, the memory 42 stores in advance a highly accurate complete image pattern that serves as a reference for comparison calculations. It is stored through the arithmetic unit 41.

This arithmetic device 41 compares each image pattern of the inspection print imaged by the camera 28 with the reference image pattern in the memory 42 according to instruction input data such as the size of the print material in the input device 43. If even one of these corresponding patterns does not match, a signal indicating the mismatch, for example, a signal of "1" or "0" is output, and a drive device, for example, a solenoid 25b is actuated to drive the gate plate 25. The printed matter 2 determined to be non-conforming is separated and discharged along the gate plate 25 to a waste paper receptacle 26 outside the system. By using such a printed matter inspection system, it is possible to collect only well-printed materials and use them for bookbinding.

Next, this print inspection system will be described in more detail along with the operation of each part of the apparatus shown in FIGS. 1 and 2.

First, among the printed materials to be inspected, one is found that is perfectly printed and can be used as a reference printed material that meets the inspection standards even when checked visually, and is placed on top of the many printed materials 2 that have been stacked. and install them in the paper feed section of frame 1.

Here, the printed material inspection device is operated normally, and the paper suction pipe 3 of the vacuum paper suction device sucks up the reference printed material, holds it between the belt 6 of the belt conveyor 4 and the guide roller 7, and transfers it to the belt 6. Then, it is sent to the vacuum belt conveyor 13 side. During this time, the reference printed matter is horizontal belt 1
0 and receives a biasing force, its side edges are lightly pressed against the side support plate 12, and lateral positioning is performed.

The head of the reference printed matter thus positioned is detected by the cue sensor 30, and
It passes under the camera box 27. During this passage, after a predetermined time (very short time) after the cue sensor 30 detects the cue, the camera 28 in the camera box 27 repeatedly takes images in the scanning direction. Thus, this camera 28 separates and images the reference printed matter into, for example, 4000 image patterns, and each pattern data is stored in the memory 42 of the arithmetic unit. Further, the reference printed matter sent in this manner is sent to the paper collection section 23 via the drum 19 and the paper discharge belt conveyor 20.

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 30, after the same predetermined time as described above, the camera 28 takes an image of the decomposed pattern in the printed state, and for each decomposed pattern, each of the reference printed matter stored in the memory is A calculation device compares and calculates the corresponding pattern and the image (by detecting the amount of light, etc.), and when the memorized reference pattern and the pattern of the inspected printed material 2 match, the calculation device outputs a “0” signal and turns on the solenoid 25b. It is kept in a de-energized state and the gate plate 25 is kept in a prone state. Therefore, the printed matter 2 that has been imaged is guided onto the drum 19 and onto the belt 22 on the paper discharge belt conveyor 20, and further onto the paper collection section 2.
3 falls on top.

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

On the other hand, printed materials with poor print quality,
If a part of the decomposition pattern obtained by the similar evaluation by the camera 28 after being detected by the cueing sensor 20 is determined to be different from the reference pattern, a "1" signal is output. This causes an energizing current to flow through the solenoid 25b, and the gate 25 is erected via the link 25a. Therefore, the printed matter 2 after passing through the camera box 27 is turned downward by the gate 25, is held between the drum 19 and the belt conveyor 24, and is discharged and accumulated on the waste paper receiver 26.

It should be noted that while each of the printed matter 2 is passing through the lower part of the camera box 27, it is necessary to take a high-precision image of the same part as the reference printed material and at the same timing, so the position determined by the side support plate 12 is maintained with high precision. There is a need. In other words, it is necessary to prevent the printed matter 2 from swinging or rolling up at this position. In order to prevent this, in this embodiment, the paper printing material 2 is placed on the belt 16, and vacuum pressure (negative pressure) introduced into the suction hole 15 is applied to the belt 16.
It is becoming more and more common for the children to be sent in close contact with each other.

As described above, according to this embodiment, it is possible to detect not only blank paper and waste paper, but also dust adhesion on the image.
It is possible to automatically detect all of the problems that normally occur with poor print quality, such as color fading, misregistration, and even color shift due to this dust, and to separate printed matter into good and bad prints.

Although not shown in the drawing, a sensor for detecting the color difference between the printing color of the printing unit and the paper is also provided, so that non-conforming printed matter can be arbitrarily discharged based on the above calculation results. I can do it.

According to the present invention, there are the following effects.

By adopting a system that compares and calculates the image pattern of the reference printed matter stored in memory in advance and the highly resolved image pattern of the inspected printed matter in the arithmetic unit based on the instruction conditions inputted with the input device. As a result, it is possible to judge whether or not the finished print is good or bad and to classify it at high speed and with high precision. In this way, in addition to being able to distribute well-printed products as they are, they can also be bound and shipped, eliminating the need to collect printed materials after shipping, and eliminating the financial burden on suppliers.

Since a diagonal horizontal belt conveyor and a horizontal support plate standing parallel to the belt conveyor are provided, the lateral positioning of each printed matter is ensured, and the printed state of the same part of each printed matter can be accurately monitored. be able to.

Since a single-sheet feeding sensor is provided, it is possible to automatically detect that printed matter is fed one sheet at a time.

Since the beginning sensor is provided, the beginning timing and end of scanning by the camera can be determined by detecting the beginning of the printed material.

Since the gate is provided to be able to rise and fall freely, if the print quality is poor, the gate can catch the poor printed material and discharge it diagonally toward the conveyor.

Since the printed matter is fed in one direction by the vacuum belt conveyor, the printed matter is suctioned and prevented from swinging or rolling up.

[Brief explanation of drawings]

FIG. 1 is a front view showing a specific device in the print inspection system of the present invention, FIG. 2 is a plan view,
3 is a sectional view taken along the line -- in FIG. 2, and FIG. 4 is a block connection diagram of the print inspection system. 3... Paper feeding means, 4... Belt conveyor, 12
...Positioning means, 25...Gating means, 28...
... Camera, 30 ... Cue detection means, 41 ... Arithmetic device, 42 ... Memory, 43 ... Input device.

Claims (1)

[Claims] 1. A paper feeding means for sucking up a large number of superimposed printed matter one by one from the top from one side of the frame and delivering it onto a belt conveyor; a horizontal support plate provided on one side of the frame so as to stand up parallel to the belt conveyor; a single-sheet feed sensor provided above the belt conveyor; a side belt conveyor that is provided diagonally with respect to the traveling direction of the belt conveyor and that supports the printed material together with the belt conveyor and brings it into contact with the side support plate; A vacuum belt conveyor that is disposed adjacent to the belt conveyor and transports the printed matter on the belt conveyor while adsorbing it; a discharge belt conveyor and a paper collection section provided on the frame; A gate means provided in a freely undulating manner between the belt conveyors, an oblique belt conveyor provided adjacently below the gate means, and a camera disposed on the vacuum belt conveyor to scan and photograph printed matter; It consists of a cue detection means that determines the scanning timing of the printed matter by the camera, and positions each printed matter to be inspected placed on the belt conveyor by the paper feeding means by a horizontal support belt and a horizontal support plate; The head of the positioned printed matter is detected by a cue detection means, and based on the detection signal of this detection means, the figure etc. on the printed matter is highly decomposed and imaged by a camera, and
Each imaged pattern is compared with a reference figure pattern stored in memory in advance in a calculation device, and when it is determined that the two patterns are different based on the calculation result, the above-mentioned printed matter to be inspected A printed matter inspection system characterized in that the printed matter is discharged by a gate means to an oblique belt conveyor in a direction different from that of the discharge belt.