JPH0578440B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for monitoring irregular pages that occurs during the bookbinding process.

[Prior art] Conventional misprint monitoring devices print marks such as spines on the backs of folded pages, detect the marks with optical sensors, and identify whether the folded pages are normal or not. .

[Problems to be Solved by the Invention] However, with this conventional device, the spine must be printed on the signature, and the position of the spine varies depending on the printed matter, so it may vary depending on the printed matter being handled. I had to adjust the installation position of the backbone detector.

In addition, since all printing paper is folded by machine, compared to the traditional hand-folding process, folding may be uneven or misaligned, and the spine may be folded in and disappear, causing the machine to malfunction or stop. I did it.

SUMMARY OF THE INVENTION An object of the present invention is to overcome the drawbacks of the prior art described above and to provide a method for monitoring irregular pages that can detect and eliminate irregular pages regardless of the type of printed matter or the presence or absence of a backing label.

[Means for Solving the Problems] The present invention illuminates a plurality of measuring points on the monitoring paper surface and the standard paper surface, respectively, and receives the reflected light with an optical sensor, in order to monitor the misprints that occur during the bookbinding process. Convert it to an electrical signal, set a defective level to the electrical signal obtained from the standard paper, and compare the number of measurement points where the electrical signal obtained from the monitoring paper exceeded the defective level with the number of all measurement points. In this method, a correction level is added or subtracted from the electrical signal of the monitoring paper in advance, taking into account changes in the intensity of reflected light from the monitoring paper, and the monitoring paper is adjusted based on the correction level. The gist of the present invention is a method for monitoring irregular pages, which is characterized by monitoring irregular pages by comparing quality at each measurement point.

[Example] The method for monitoring irregular pages of the present invention includes first storing a signal of the lowest page of a standard signature in a memory, then storing a signal of the lowest page of a monitored signature in another memory, Compare the two to determine whether the pages are different.

In the method for monitoring irregular pages of the present invention, a plurality of points on a sheet of paper are used as measurement points. For this reason, the sensor section of the misprint monitoring device according to the present invention includes a plurality of optical sensors.

However, this comparison could simply be made as E ₁ −E ₁ ′=0 (E ₁ is the signal of the standard paper measured by one optical sensor, and E ₁ ′ is the signal of the monitoring paper). There is a risk that any irregularities in the paper surface, measurement errors, positional deviations, etc. will be judged as defective. Therefore, we set E ₁ −E ₁ ′<±M, and let M be the defect level that is expected to occur when measuring the amount of reflected light at the same position.
It is determined that the signals are not the same beyond this point.

However, microscopic differences often occur even on the same page due to a single spot of dirt or small print irregularities. For this reason, when two paper surfaces are measured and the individual measurement points are compared, there may be some points that do not give the same signal depending on their positions. Therefore, in the present invention, the points that are defective by comparing the same positions with each other are totaled, and the ratio of the number of defective points to the number of all measurement points is set in advance, and the defective points are determined in this ratio. When the number of pages exceeds , it is determined that the paper being monitored is of a different type.

The principle explained above is illustrated in FIG. 1.

The vertical axis indicates the amount of light reflected from the paper surface. Axis A indicates the level of the pure white paper surface, and axis B indicates the level of the pure black paper surface. Also, A, B, C, etc. indicate the measurement position, that is, the position of the optical sensor. Therefore,
In this example, seven optical sensors are provided in the sensor section.

Signal 100 indicates a standard paper signal; signal 10
0a is a signal obtained by adding the defective level M to the signal 100, and signal 100b is a signal obtained by subtracting the defective level M from the signal 100. If the monitored paper surface is measured and a predetermined number or more of measurement points are found between the signal 100a and the signal 100b, the measured paper surface is determined to be the same type of paper surface.

Now, even though the monitored paper surfaces are of the same type, the density of the ink may change over time, or the amount of reflected light may differ due to differences in the material of the paper surface, resulting in different types of paper. In order to avoid such discrimination errors, the correction level α is added or subtracted from E ₁ ′ and compared as E ₁ − (E ₁ ′±α)<±M, and the difference in the amount of reflected light is corrected for judgment. Try to lower it.

For example, when the ink on the monitoring paper is dark, the signal 101 (FIG. 1) of the monitoring paper approaches axis B as a whole. If the signal 101 is compared with the signal 100 as it is, it will be determined that the monitored paper is of a different type, so a correction level α is added to the signal 101 and the signal 101' is used for comparison.

Hereinafter, a preferred embodiment of the present invention will be described with reference to FIG.

FIG. 2 shows a block diagram of a misprint monitoring device that implements the method of the present invention.

The sensor unit 1 is connected to a folding stacking table (hereinafter referred to as
It is fixed to the collating machine (simply a frame) and monitors the bottom page of the signatures stacked on the collating machine frame. For example, if there are n frames, n sensor units 1 are also required. No.1...No.n indicates the frame number. The sensor section 1 is composed of a plurality of optical sensors. Therefore, the misprint monitoring device of the present invention uses a plurality of points as measurement points. The sensor unit 1 is made to reflect the light from a light source lamp onto the paper surface, and convert the reflected light into an analog quantity of electricity using an optical sensor. The output of the sensor section 1 is amplified by an amplifier 2. The amplifier 2 is preferably a buffer amplifier that performs impedance conversion in order to prevent noise and the like from entering.

The amplified signal is sent to multiplexer 79. The analog signal is time-divided by the multiplexer 79 and sent to the AD converter 13 one after another. In the AD converter 13, the analog signal is converted into a digital signal.

Through this operation, the analog signal is stored as a digital signal in the storage circuit 75 for each measurement point according to instructions from the memory controller 14.

The case where there is one frame will be described below. The same idea can be applied to the case where there are multiple frames.

The memory circuit 75 can be broadly divided into a standard memory 15 and a monitoring memory 16 based on their roles. There is no functional difference between the standard memory 15 and the monitoring memory 16. The memory 15 stores information on the standard paper, and the memory 16 stores information on the monitored paper. The operations of memory 15 and memory 16 are as follows.

The contents of the memory 16 are stored in the level failure detector 31.
The data is compared with the contents of the memory 15, and if there is a difference of more than a predetermined defect level M, it is detected as a defective point. In other words, the first standard page of the memory 15
Information on the th measurement point (hereinafter referred to as E ₁ ) is derived to the level failure detector 31 . Next, the monitoring paper in the memory 16 contains information on the first measurement point (hereinafter referred to as E ₁ ').
is guided to the level defect detector 31. Then, the level defect detector 31 determines whether E ₁ ' is a defective point by determining E ₁ −(E ₁ ′±α)<±M. The modification level α is arbitrarily set by the modification level setter 90. For example, when there is no change in the density of ink on the standard paper surface, the level α is set to 0. The defective level M is arbitrarily set by the defective level setter 32.

If E ₁ ' is a defect signal, one pulse is sent from the level defect detector 31 to the defect rate detector 51. The defect rate detector 51 counts the number of pulses. Next, the information on the second measurement point on the standard paper (E ₂ ) and the information on the second measurement point on the monitoring paper (E ₂ ′) are compared in the same way, and it is determined whether E ₂ ′ is a defective signal or not. Please be judged. This operation is performed for all measurement points.

When all measurement points are compared in this way, the number of defective signals is stored in the defective rate detector 51. Whether or not a signature is defective is determined based on the ratio of the number of defective signals to the total number of measurement points.

The defective rate setter 42 sets the proportion of defective signals to the total number of measurement points. For example, if the defective rate setting device 42 is set to 20%, all measurement points are set to 10%.
Two points is the limit for the number of defective signals. These two pieces of information are sent from the defective rate setter 42 to the defective rate detector 51. The number of defective signals is stored in the defective rate detector 51, and the number of defective signals is compared with the information sent from the defective rate setting device 42, and the signals indicating whether the monitored paper is of the same type or different types are continuously displayed. It is sent to the defect occurrence detector 61.

The continuous failure occurrence detector 61 issues a failure command to a command circuit (not shown) as a final failure only when the number of failure determinations reaches the number set by the continuous failure count setting device 62. If the consecutive defective count setting device 62 determines that even one sheet is defective, it can issue a defective command, but in the case of misprinted pages due to a loading error, about 50 to 100 sheets will be defective in a row, so it is possible to issue a defective command. If the number of times setter 62 is set to 3, for example, a defect command will be issued only when a defect is found three times in a row. The setting of the number of consecutive failures setter 62 can be set arbitrarily, and this number of consecutive failures setter 62 makes it possible to monitor only irregular pages due to loading errors. The final defect determination sent to the command circuit is notified to the operator by sounding a buzzer or stopping the collating machine.

It is also possible to automatically set the failure level M in the failure level setter 32 and the failure rate in the failure rate setter 42. FIG. 2 shows an embodiment in which the defective level M and the defective rate are automatically set.

When a standard sheet is placed on the folding table, the automatic discrimination level setting device 86 sets the defective level M and the defective rate by the following operation.

For example, if there are frames from No. 1 to No. 6, No.
The standard paper surfaces are compared in all 15 combinations, such as the No. 1 standard paper surface and the No. 2 standard paper surface, the No. 1 standard paper surface and the No. 3 standard paper surface, and so on.
At this time, the defective level M and the defective rate are set to appropriate values. Comparison between standard sheets is performed according to instructions from the memory controller 14. Since there are no two standard papers that are the same, if even one set of standard papers is determined to be of the same type, the set values for the defective level M and the defective rate are large. Therefore, the value of the defective level M or defective rate is automatically reduced by the automatic discrimination level setter 86. Conversely, if all the standard sheets are determined to be "different types", the values of the defective level M and the defective rate are sufficiently small. However, if the value of defective level M and defective rate are too small, "same type"
Since a discrimination error may occur in which the defective level M and defective rate are determined by the discrimination level automatic setter 8.
6 makes it slightly larger.

The automatic discrimination level setter 86 repeats the above operations and sets the highest defective level M and defective rate that can distinguish all standard sheets from each other in the defective level setter 32 and defective rate setter 42. be.

[Effects of the Invention] As described above, according to the present invention, the correction level α can be added or subtracted from the actual measurement value by the optical sensor for comparison. It is possible to accurately correct changes in the amount of reflected light due to differences in materials, etc.
Therefore, there are very few errors in determining whether the same type of paper is a different type of paper.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing the principle of the method for monitoring disordered pages of the present invention, and FIG. 2 is a block diagram showing an example of a disorderly pages monitoring apparatus that implements the method of the present invention. 1...Sensor section, 2...Amplifier, 13...
AD converter, 14...Memory controller, 15...Standard memory, 16...Monitoring memory, 31...Level defect detector, 32...Failure level setter, 42...Failure rate setter, 51...
Defective rate detector, 61...Continuous failure occurrence detector, 6
2...Continuous failure count setter, 86...Discrimination level automatic setter, 90...Correction level setter.

Claims (1)

[Claims] 1. To monitor irregular pages that occur during the binding process,
Light is applied to multiple measurement points on the monitoring paper and the standard paper, the reflected light is received by an optical sensor and converted into an electrical signal, and a defect level is set on the electrical signal obtained from the standard paper for monitoring. In the method of monitoring misprinting by comparing the number of measurement points where the electrical signal obtained from the paper surface exceeds the defective level with the number of all measurement points, changes in the intensity of reflected light from the monitoring paper surface are taken into consideration. A method for monitoring irregular pages, characterized in that a correction level is added to or subtracted from an electric signal of the monitored paper surface in advance, and the quality of the monitored paper surface is compared at each measurement point based on the correction level to monitor misprinted pages.