JP2526862B2 - Printing paper tension control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention is intended to improve and stabilize print quality by keeping the tension of running paper in a printing section in an optimum state during operation of a take-up printing machine. The present invention relates to a printing paper tension control device.

[Prior art and its problems]

In a take-up printing machine that has a plurality of printing units and a web-shaped printing paper (hereinafter referred to as running paper) is subjected to multicolor printing by passing through each printing unit, the running paper in operation is It behaves as shown in FIG. FIG. 3 is a schematic explanatory view of a cross section of one printing unit of the take-up rotary press, in which (301a) and (301b) are plate cylinders and (302a).
(302b) is a blanket cylinder, (303) is a printing portion for actually transferring ink to the running paper, (304) is a regular route of the running paper, and (305) is an actual position of the running paper. The running paper is pulled on the blanket cylinder by the tack of the ink even after the ink has been transferred at the printing pressure section (303). When the running paper leaves the blanket cylinder, the blanket cylinder is aligned with the running paper route (304), Depending on the conditions such as the difference in the amount of pattern (ink) on the front and back of the printing pressure part (303) and the presence of the notch (306) for rolling up the blanket cylinder, it is pulled by either the upper or lower blanket cylinder, It shows a behavior that the vehicle deviates from the route (304) and travels at a position like (305) shown in the figure.

In this example, since the blanket cylinder (302a) is located downstream of the blanket cylinder (302b), the running paper is pulled toward the blanket cylinder (302a).

Further, since the elongation rate of the running paper due to tension differs from about 0.7% to 2.5% depending on the type of printing paper, the amount by which the running paper leaves the regular route (304) varies depending on the paper even with the same tensile rate. However, the regular route (30
If the tension of the running paper is extremely increased in order to make the distance from 4) extremely small, problems such as breakage of the running paper and wrinkles occur.

Therefore, the tension often has to be adjusted to an appropriate value, but the conventional tension adjustment of the printing unit visually confirms the behavior such as a state where a person separates from the blanket cylinder of the running paper in the printing unit, and the running paper is A person adjusts the tension by manipulating an adjustment dial, a handle, etc. of a tension setting section provided in the paper feeding section installed immediately before entering. The tension setting unit detects the tension of the running paper with the tension detecting unit of the sending unit, and increases or decreases the speed of sending the running paper with the acceleration / deceleration device of the drive unit to maintain the set tension force. It is a mechanism to do. However, even if a constant tensile force is applied to the running paper, it is not possible to control the behavior of the running paper to an optimum state because the position where the actual running paper flows changes when the various printing conditions described above change. .

 The problems in the above-mentioned conventional technique are as follows.

Since the behavior of the running paper cannot be controlled with the conventional tension setting device of the feeding section, humans often have to adjust the tension setting value, resulting in poor print quality reproducibility due to variations in the tension setting value, and loss of work time. Etc. occur.

When the proper value of the tension cannot be obtained, the position where the running paper flows changes, so that the distance of the running paper between the printing portions of the respective colors also changes, resulting in deterioration of print quality such as double color and misregistration between colors.

The amount of pulling of the running paper differs depending on the amount of the pattern (ink) of each printing unit, and unless the tension is adjusted with reference to the printing unit with the large amount of pulling, the effect of tension adjustment cannot be obtained.

[Object of the Invention]

The present invention has been devised to solve the above problems, and detects the behavior of running paper that changes depending on conditions such as various paper qualities, print patterns, and inks, and automatically controls the tension set value. By adjusting the tension,
It is an object of the present invention to provide a printing paper tension control device that further stabilizes it.

[Outline of Invention]

The present invention made to achieve the above object is a printing paper tension control device for a take-up printing machine, which has a plurality of printing units and performs multicolor printing on a web-shaped printing paper, and immediately after printing in each printing unit. A plurality of detecting means for detecting the behavior of the printing paper, a displacement amount calculating means for obtaining a displacement amount based on signals from the plurality of detecting means, and a tension correction signal for comparing the obtained displacement amount with a reference value. Is a printing paper tension control device comprising: a correction signal generating means for generating the above value; and an adjusting means for adjusting the tension value based on the correction signal.

[Constitution and operation of invention]

A first embodiment of the printing paper tension control device of the present invention
This will be described below with reference to FIGS.

FIG. 1 is a schematic diagram showing the installation positions of a sensor head for detecting the behavior of running paper in each printing unit and a tension adjusting unit in the printing paper tension control device of the present invention.

The tension control device of the present invention detects the actual position (103) of the running paper, which is indicated by being pulled by the blanket cylinder (101a), immediately after the running paper has passed through the blanket cylinder (201a). ), The control main body (104) detects and processes the displacement amount (106) from the regular route (105) to the position (103) of the running paper, and the tension adjusting unit (107) of the take-up feeding unit is detected. ) In the motor (1
The displacement amount (106) is controlled by rotating (08) and changing the tension setting value. The sensor heads (202) (203) (20
4) is installed, these sensor heads are connected to the control body, and the same processing as the above is performed.

Generally, when the tension value is increased, the displacement (10
6) decreases, and the amount of displacement (10
6) will increase.

Next, the configuration and operation of the control body (104) in the tension control device of the present invention will be described with reference to the block diagram of FIG.

The signals from the sensor heads (201) (202) (203) (204) are input to the distance detection units (206) (207) (208) (209), which are detected by the timing control unit (205). A plurality of sampling data are output per one rotation of the plate cylinder based on the sampling timing signal.

The signal from the sensor head fluctuates according to the displacement of the running paper, and in this embodiment, the greater the displacement, the smaller the distance from the sensor, and therefore the number of light receiving portions of the sensor increases and the output signal increases. The distance detection unit converts the sensor output signal into distance (acceptance amount) data at the sampling timing described above, and outputs this.

Further, the timing control section (205) receives the pulse signal from the rotary encoder (215) attached to the plate cylinder or the blanket cylinder of the printing machine, and generates the above timing signal.

The distance detection units (206) (207) (208) (209) are connected to the calculation unit (218), and based on the displacement amount data from each distance detection unit in the calculation unit (218), for example, every one rotation of the plate cylinder. Calculate the maximum and average values. (210) is a maximum value comparison unit that compares the reference value for the maximum value preset by the reference value setting unit (212) with the maximum value data obtained by the calculation unit (218), Determine if tension adjustment is needed.

Further, (211) is an average value comparison unit, which compares the reference value for the average value preset by the reference value setting unit (219) with the average value data obtained by the calculation unit (218),
Determine if the run paper tension needs to be adjusted.

That is, the maximum value comparison unit (210) is an object of tension adjustment for the displacement amount of all sampling data from each printing unit, finds the maximum value from all the sampling data at regular intervals, and determines the maximum value. If the value is within a certain allowable range as a result of comparison with the reference value, the tension adjustment is not necessary, and if it exceeds the allowable range, the tension adjustment is necessary and a correction signal is output.
Further, the average value comparison unit (211) is provided to detect this and return to a normal state when the total amount of displacement increases even if there is no protruding displacement. As a result of comparison with the reference value, if the tension is within a certain allowable range, it is not necessary to adjust the tension, and if it exceeds the allowable range, it is necessary to adjust the tension and a correction signal is output.

(213) receives a tension correction signal from the maximum value comparing section (210) and the average value comparing section (211), and outputs a signal for driving the motor (108) of the tension adjusting section (107) by a predetermined amount. It is a tension operating part that changes the tension setting value as a result of the motor (108) being driven.
The position of the running paper, that is, the amount of displacement changes.

Further, by detecting the corrected displacement amount again and repeating the same processing, it is possible to obtain an appropriate tension of the running paper.

In addition, the maximum value comparison unit (210) and the average value comparison unit (2
11) is connected to an abnormality detection circuit (216), and the abnormality detection circuit (216) determines that there is a tension abnormality when receiving a tension correction signal from the maximum value comparison unit (210) and the average value comparison unit (211), An abnormal signal is sent to the notification unit (217) composed of a display, a buzzer, etc. to notify the operator that there is an abnormal tension.

As described above, the running paper can be maintained at an appropriate tension. However, in addition to the above-described embodiment, for example, the tension correction amount is set to the magnitude of the correction signal from the maximum value comparison unit and the average value comparison unit. It may be determined in association with each other, and the motor may be driven by the correction amount. Further, the sensor head may be installed on the opposite side to the traveling paper of this embodiment, and in this case, when the displacement is large, the output signal from the sensor is correspondingly small.

Further, the type of sensor is not particularly limited as long as the displacement state can be detected.

〔The invention's effect〕

As described above, according to the present invention, the detection unit, the control unit,
By controlling the tension value of the running paper in the take-up printing machine to an appropriate value with a simple device configuration and processing using an operation motor for tension adjustment, it is possible to improve the quality of printed matter, stabilize reproducibility, and even register between colors. By reducing the amount of fluctuation, there are excellent effects such as reducing print adjustment time and paper loss.

[Brief description of drawings]

FIG. 1 is a schematic external view showing a mounting position and the like of a printing paper tension control device of the present invention to a printing machine, FIG. 2 is a block diagram showing an overall configuration of the printing paper tension control device, and FIG. FIG. 4 is a schematic side sectional view showing the behavior of the running paper in the printing section of the take-up printing press. (201) (202) (203) (204) …… Main body of control (218) …… Calculation unit (210) …… Maximum value comparison unit (211) …… Average value comparison unit

Claims (3)

(57) [Claims] 1. A printing paper tension control device for a take-up printing press, comprising a plurality of printing units, for performing multi-color printing on a web-shaped printing paper by using inks. Ink of the printing paper immediately after printing in each printing unit. Detecting means for detecting the behavior in the direction of being pulled by the tack, displacement amount calculating means for obtaining a displacement amount based on a signal from the detecting means, and comparing the obtained displacement amount with a reference value to obtain a tension correction signal. A printing paper tension control device, comprising: a correction signal generating means for generating the tension; and an adjusting means for adjusting a tension value based on the correction signal. 2. The printing paper tension control device according to claim 1, wherein the displacement amount calculated by the displacement amount calculating means is a maximum displacement amount and an average displacement amount for each fixed period. 3. The printing paper tension control device according to claim 1, further comprising abnormality display means for displaying a tension abnormality when the displacement amount obtained by the displacement amount calculation means exceeds an allowable range. .