JPS62287110A - Pitch measuring instrument for printing mark - Google Patents

Abstract

PURPOSE:To accurately measure mark pitch and to prevent a defect in pitch by counting pulses that a rotary encoder coupled directly with a guide roll shaft outputs and detecting the angle of rotation of the guide roll between printing marks. CONSTITUTION:The output of a photoelectric converter 5 for reading printing marks is amplified by a circuit 8, a mark signal digitized by a converting circuit 9 is inputted to a gate circuit 10, and the gate signal from one mark 2 to another mark 2 is inputted to a counter circuit 11. Output pulses from the rotary encoder 7 coupled directly with the guide roller 6 are inputted to and counted by the circuit 11, whose counted value is latched by a circuit 12 and stored until a next mark pitch is counted; and the stored value is inputted to comparing circuits 13 and 13'. The upper- and lower-limit values of desired printing mark pitch data set by the circuits 14 and 14' are inputted to the circuits 13 and 13' and when a measured value varies beyond the set value range, the circuits 13 or 13' generate an output to increase or decrease the tension of a printing machine.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention [Technical Field of the Invention] The present invention relates to a printing mark (2) on a printing material (1) printed by gravure printing or the like as shown in FIG. Pi + (d
1 to d5).

[Technical background of the invention and its problems]

The pinch of printing marks on a roll-up printing material printed by gravure printing etc. may not be printed at the specified pitch due to the expansion and contraction of the printing material. ``There is no means to measure the flatness, so we have to manually measure it with a scale, etc.''
Ta. However, since the measurement is carried out manually, there are inconveniences such as variations in measurement values depending on the measurer and inaccurate measurement values.

The present invention was devised to compensate for these drawbacks.
To provide a means for automatically measuring the pinch of a printed mark without human intervention.

In addition, manual measurements cannot keep up with the printing speed, and it is impossible to determine fi11 between the printing machine and online.
I was reluctant to know immediately that the mark pinch was defective.

[Purpose of the invention]

The present invention has been made based on the above-mentioned circumstances, and its purpose is to accurately measure the pitch of printed marks on a printing press and online with the printing press, while being simple and simple. It is an object of the present invention to provide a pitch measuring device for printed marks that can immediately detect pitch defects.

[Summary of the invention]

In order to determine this, the printed marks are read at a fixed point on the printing press from the printing substrate that advances one after another using a photoelectric converter. On the other hand, a rotary encoder is directly connected to the guide roll shaft on which the above-mentioned printing material runs, and by counting the number of pulses output from the rotary encoder between the above-mentioned print mark and the next above-mentioned print mark, the print mark and the print mark are The number of rotations or the rotation angle of the guide roll between is obtained.

Next, even if the rotation speed or rotation angle between the printing marks obtained in this way is determined, this rotation speed or rotation angle is corrected by the outer circumference length of the guide roller of the printing machine, and the rotation speed or rotation angle of the reference outer circumference length is corrected. Find the angle.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 3 shows an external view of a printing mark pitch measuring device mounted on a printing press. (1) is a running reel-type printing material, (2) is a printing mark, (3) is a transmission illumination light source, (4) is a reflection illumination light source, (5) is a photoelectric converter, (
6) indicates a guide roller for the traveling film or paper, and (7) indicates a rotary encoder directly connected to the axis of the guide roller.

The number of pulses per rotation of the rotary encoder (7) is arbitrarily selected according to the outer circumference length of the guide roller (6), and in this example, the outer circumference length to the guide roller (6) is 100 mm. , rotary encoder (
The number of pulses per rotation in 7) is 1000 pulses. Therefore, one pulse signal is output from the rotary encoder (7) every time the printing material (1) advances by 01 mm. Of course, pulses such as 2000.3000 may also be used. In addition, the running printing material (1) includes:
In addition, a meandering prevention device and a flapping prevention device (not shown) are incorporated to prevent lateral meandering or vertical flapping.

Next, the printed mark pitch determination device according to the present invention will be explained in more detail with reference to the block diagram shown in FIG. It is digitized by the A/D conversion circuit (9). The digitized mark signal is input to a gate circuit (10). A gate signal from mark to mark is generated in the gate circuit (10) and input to the next counter circuit (11). On the other hand, the output pulses from the rotary encoder (7) are input to the counter circuit (11). As a result, the gate circuit (
Count the number of rotary encoder pulses input to the counter circuit (11) while the gate signal is being output from the counter circuit (10). The count data is stored in the latch circuit (
12), the count data is stored until the next mark pitch is counted, and input to the next comparison circuit (13) and (13)'.
In addition, setting data is input from data setting circuits (14) and (14'). The data set by the data setting circuit (14) is the upper limit value of the desired print mark pitch data, and the data set by (14') is the lower limit value. As a result, comparison circuit (13) and Q3
From 1), if the measured value of the print mark pitch does not exceed the set value range, no output signal is output, and if it exceeds the set value range, an output signal is output. Note that the output signals from the comparison circuits (13) and (13) are directly used to control the tension of the printing press.In other words, the output signals from the comparison circuit (13) are used to control the tension to weaken, and vice versa. The output signal from the circuit (13) is controlled to increase the tension.

In this embodiment, the guide roller (6) shown in FIG. 3 has an outer circumferential length of 100 mm, and the rotary encoder (7) has a
I used one with 1000 rotation pulses, but the outer circumference length of the guide roller of the printing press is of various sizes, so the relationship between the output pulse number of the guide roller and the rotary encoder is always 1 pulse/Q, 1 mm. Not exclusively. Therefore, as shown in Fig. 1, the latch circuit (1
A data correction circuit (15) is provided between 2) and the comparison circuit ω) and (14) to correct the relationship between the outer circumferential length of the guide roller and the number of output pulses of the rotary encoder.

That is, if the circumferential length of the guide roller is 250 mm, 1
Pulse/U, 25mm, data correction circuit (15)
Now, the latch data output from the latch circuit (12) should be multiplied by 2.5. It is preferable that this data correction circuit (15) is configured by a microprocessor and can freely perform arbitrary corrections.

〔Effect of the invention〕

It is now possible to instantly measure the pitch of printing marks on the printing material online on the printing press, corrected to accurate data. Therefore, this makes it possible to immediately determine the pitch defects of printed marks, and by using this data, it is possible to prevent pitch defects of printed marks.

[Brief explanation of drawings]

FIG. 1 is a block diagram of the apparatus of the present invention, FIG. 2 is an external view of printing marks printed on a printing substrate, and FIG. 3 is a diagram of a printing mark pitch measuring device installed on a printing press. The external view and FIG. 4 are block diagrams. (1) Printing substrate (2) Printing mark (3) Transmission illumination light source (4) Reflection illumination light source (5) Photoelectric converter (6) Guide roller (7) Rotary encoder (8) Amplification circuit (91A/D conversion Circuit (]0) Gate circuit (11) Counter circuit
(12) Latch circuit 03 comparison circuit (
14) Q4 redata setting circuit (15) Data correction circuit

Claims (1)

[Claims] a photoelectric converter that reads printing marks provided at regular intervals in advance on a rolled-up printing material; and an A/D conversion circuit that digitizes a signal output from the photoelectric converter; A rotary encoder provided on a guide roll shaft on which the printing material runs, a pulse count circuit that counts output pulses from the rotary encoder, and a pre-obtained correction for pitch measurement data obtained based on the count results. A printing mark pitch measuring device equipped with a correction circuit that corrects by value.