JPH0648630A - Emergency stopping device and method - Google Patents

Abstract

PURPOSE:To prevent paper feed stop at the time of an emergency stop of an offset rotary press and to apply suitable braking. CONSTITUTION:With a main switch 6 turned off, a tension controller 5 issues an emergency braking command corresponding to a diameter, which is measured by a diameter measuring device 15, and a speed. When a dancer roller 7 goes down because of the slack, the tension is given by this dancer roller 7. When the dancer roller 7 returns, a start level command is outputted from the tension controller 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an emergency stop apparatus and method for an offset rotary printing press, which prevents web breakage due to an emergency stop of a main machine.

[0002]

2. Description of the Related Art A rotary offset printing press generally includes a paper feed section, a printing unit, a drying / cooling section, and a cutting / cutting section.
It has a fold. In this case, in the cutting / folding section, attention is particularly paid to a paper jam of the folding machine with the recent increase in the speed of the machine, and a paper jam detecting device is provided. If a paper jam occurs, an emergency stop is applied before the machine is damaged. Also, if the web is scratched, so-called paper breakage may occur, and the broken paper may wind around the blanket in the printing unit, resulting in damage to the bearing. Therefore, an emergency stop is applied even when a paper shortage is detected.

On the other hand, the web roll of the paper feeding section is provided with a brake for controlling the tension of the web, and the control of the braking force controls the rotation of the web roll and thus the unwinding speed of the web. However, at the time of the emergency stop, the inertia of the web roll prevents the web roll from following the stoppage of the machine, and the web is unwound to cause slack. The generation of the tensionless web due to the occurrence of the slack causes wrinkles and meandering of the web, and the infeed roller and the guide roller existing in the next stage are caught or wrinkled, which leads to a paper break. Further, when a force is applied to the web and the web suddenly stops in a tensioned state, the web is once slackened, and then the tensioning operation is repeated.

Hitherto, there has been proposed a means for applying a braking force several times the normal braking force to stop the web roll at such an abrupt stop, and stopping the web roll as soon as possible. Even if a force is applied, it is conceivable that a large-diameter web roll will still sag due to its inertia and brake operation delay.

When the web is slackened due to an emergency stop, the slack is rewound on the web roll to be stored in the original roll. It cannot be said that sufficient measures are taken against paper breaks due to repeated loosening and tension, and even if the web roll is rewound after the slack is reduced by performing an early stop based on the above-mentioned conventional technique,
Even if a large braking force is uniformly applied to the web roll, it does not take into account the roll diameter of the web roll.Therefore, there is a difference in the stopped state between high speed with a large diameter roll and high speed with a small diameter roll. However, even in this respect, it cannot be said that sufficient measures have been taken against paper breaks.

In view of the above problems, the present invention applies a braking force suitable for the state at the time of an emergency stop, and does not make a tensionless state even if a slack occurs to prevent a paper break. The purpose of the present invention is to provide an emergency stop device and its method.

[0007]

The present invention which achieves the above-mentioned object comprises (1) means for detecting the current speed of the web drawn from the web roll and means for detecting the current diameter of the web roll, A tension controller that outputs an emergency brake command to the brake of the web roll based on the current speed and the current diameter by the detection means when the main switch is turned off.

(2) The speed of the web drawn from the web roll and the diameter of the web roll are detected, and when the main switch is turned off, the web roll is issued by an emergency braking command based on the speed and the diameter at that time. It is characterized by applying the brake of

(3) A dancer roller that descends due to the slack of the web is provided between the web roll and the infeed roller that draws the web from the web roll, and further,
A means for detecting the current speed of the web drawn from the web roll and a means for detecting the current diameter of the web roll are provided. A tension controller that outputs an emergency brake command to the brake and that changes the emergency brake command to a start level command when the dancer roller that descends due to the slack of the web based on the emergency brake of the web roll returns to the start level command is provided. And

(4) The speed of the web drawn from the web roll and the diameter of the web roll are detected, and when the main switch is turned off, the web roll is issued by an emergency braking command based on the speed and the diameter at that time. Is applied, and then the emergency brake command is changed to a start level command when the dancer roller descends based on the slack of the web.

[0011]

With the above configuration, when applying the braking force to the web roll during an emergency stop, the braking force of the web roll is applied in consideration of the diameter of the web roll and the speed of the web at that time. The appropriate braking force can be obtained to reduce paper breakage, and even if the web sags, the dancer roller applies the web tension and the emergency braking force starts when the web roller stops. By changing the brake to the above, it is possible to reliably prevent the web from breaking.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Now, an embodiment of the present invention will be described with reference to FIGS. FIG. 1 mainly shows the configuration of the paper feed unit, and the description will be given on the premise that the paper feed unit includes a flying type automatic paper splicing device. In FIG. 1, 1 is a web roll provided on a reel stand (not shown), a shaft end brake (not shown) for tension control and an emergency stop provided on the web roll 1, 3 is the web roll 1 and an infeed A tension detector 4 for detecting the tension of the web 2 between the roller 13 and the electro-pneumatic converter (electric signal-pneumatic converter) 5 for controlling the shaft end brake based on the tension detected by the tension detector 3 is an electro-pneumatic converter. It is a tension controller that sends a command to the empty converter 4. Such a structure forms a tension control feedback loop, and the tension of the web 2 at the paper feed portion is determined by the pulling force of the infeed roller 13, the weight of the web roll 1 and the shaft end braking force, and is detected by the tension detector 3. A command is output from the tension controller 5 to control the electropneumatic converter 4 so that the tension becomes the target tension during the normal high-speed steady operation, and the braking force according to the winding diameter is applied to the web roll 1.

Web roll 1 and infeed roller 13
On the web path between them, and in FIG. 1 between the web roll 1 and the tension detector 3, the dancer roller 7
Are arranged. The dancer roller 7 is capable of swinging up and down, and is provided with a pressurizing means for applying an air pressure against the tension of the web 2 and a vertical swing position detecting means 12 of the dancer roller 7. There is.

The pressurizing means provided in the dancer roller 7 includes a piston rod 9 connected to the dancer roller 7, an air cylinder 8 for moving the piston rod 9, and an air cylinder 8 for instructing the air cylinder 8 based on a command from the tension controller 5. It has an electropneumatic converter 10 for feeding pressure.
The air pressure applied to the dancer roller 7 is slightly lower than the pressure corresponding to the tension when the web 2 is pulled by the infeed roller 13 from the web roll 1. Therefore, in the state of the tensile tension (target tension) during the normal high-speed operation by the infeed roller 13, in other words, in the steady state, the dancer roller 7 is fixed to the upper end position by this target tension, and functions similarly to the fixed roller. . In the state where the web 2 is slackened at the time of emergency stop, the dancer roller 7 is pushed down by this air pressure, and the web 2 functions to be stretched without tension.

The air cylinder 8 relieves the shock of the dancer roller 7 generated when the slack of the web 2 is removed by pulling the infeed roller 13,
A damper 11 such as a spring is provided. The damper 11 such as the spring may be provided at the fixed (end) position of the dancer roller 7.

As means for detecting the vertical swing position of the dancer roller 7, there is provided a potentiometer 12 whose resistance value changes according to the vertical position of the dancer roller 7. The detection signal of the potentiometer 12 is input to the tension controller 5. It That is, the vertical position of the dancer roller 7 can be input to the tension controller 5 as an electric signal.

An infeed roller 13 is provided downstream of the tension detector 3 shown in FIG. The infeed roller 13 is provided with a major encoder 14 that detects the length (feed amount) of the web 2 that has passed through the roller 13, and the measurement value of the major encoder 14 is input to the diameter measuring device 15. It On the other hand, a sensor 16 for detecting one revolution of the web roll 1 is provided, and the output of this sensor 16 is input to the diameter measuring device 15. In the diameter measuring device 15, the traveling amount of the web 2 per constant time is obtained to obtain the speed of the web 2, and the circumferential length of the web roll 1 is obtained from the traveling amount of the web 2 per one revolution of the web roll 1. Web roll 1 by multiplying it by (1 / π)
Seeking the current diameter of. Then, the speed of the web 2 and the current diameter of the web roll 1 are determined by the tension controller 5
Entered in. In the steady running printing state, the speed and the current diameter are parameters for calculating the braking force.

Further, an ultrasonic sensor 17 for measuring the outer diameter of the web roll 1 is provided near the web roll 1. Although this ultrasonic sensor 17 is not as accurate as the current diameter measured by the diameter measuring device 15, the outer diameter of the web roll 1 can be obtained with the web roll 1 placed on the reel stand even when the web 2 is not being unwound. It is used to calculate the start level. Here, the start level is a braking force that is loosely applied by the roll diameter even when the web roll 1 is stopped, and prevents roll rotation due to roll eccentricity. This ultrasonic sensor 1
The value measured by 7 is also input to the tension controller 5.

The operation in the emergency stop state in the configuration shown in FIG. 1 as described above will be described. When an emergency stop is applied due to a paper jam or paper shortage, the main switch 6 of the main motor
Is turned off. When this off signal reaches the tension controller 5, the web roll diameter and the web speed at that time are fetched from the diameter measuring device 15, and an emergency braking force corresponding to the web speed and the roll diameter is commanded to the electropneumatic converter for braking 4. . The braking force at this time is given by the following formula.

[0020]

[Equation 1]

This emergency stop braking force is applied to the web roll 1
As a result, the web roll 1 suddenly stops, but due to the inertia of the web roll 1, the web 2 does not stop immediately and the web 2 sags. This slack is dancer roller 7
Therefore, even if the web 2 sags, it is decelerated while maintaining the minimum tension. When the deceleration operation of the web roll 1 is stopped, the dancer roller 7, which has descended due to the slack, moves up again and returns.
The output of the potentiometer 12 for reversing (returning) the dancer roller 7 at this time is detected every 100 msec, for example, and is detected by comparing the previous output with the present output, and the tension controller 5 starts based on the ultrasonic sensor 17. A brake command is given to the electropneumatic converter 4 by switching to a level braking force. As a result, even if the dancer roller 7 rises, the dancer roller 7 can be smoothly returned without giving a shock to the web 2.

In such an emergency stop state, the main switch 6 is turned off, the steady braking force of the sudden stop output of the braking force, the emergency braking force, the change of the start level, the dancer roller 7
FIG. 2 shows a time chart for detection of rising return of the. In addition,
In the case of an emergency stop, the tension control by the tension detector 3 and the brake control by the slack detection of the potentiometer 12 of the dancer roller 7 are not performed, and only the emergency braking command by the diameter and speed from the diameter measuring device 15 is output from the tension controller. The start level brake command is output only when the dancer returns.

In the above description, the speed and the diameter of the web were obtained by the sensor and the measure encoder 14. However, if the required accuracy is obtained, the diameter can be known by using the ultrasonic sensor or the laser displacement meter, Further, the braking force is not limited to air, and each of disc and powder brakes can be used.

[0024]

As described above, according to the present invention, an appropriate braking force is applied to the web roll even in the emergency stop state, and tension is applied even if the web roll is bent, so that the dancer roller is restored. Can be performed smoothly, no paper breaks occur, and re-driving can be performed smoothly.

[Brief description of drawings]

FIG. 1 is a simplified configuration diagram of an embodiment of the present invention.

FIG. 2 is a time chart of an emergency stop.

[Explanation of symbols]

 1 web roll 2 web 3 tension detector 4,10 electropneumatic converter 5 tension controller 6 main switch 7 dancer roller 8 cylinder 9 piston rod 11 damper 12 potentiometer 13 infeed roller 14 measure encoder 15 diameter measuring device 16 sensor (1 rotation) Detection) 17 Ultrasonic sensor

Claims (4)

[Claims] 1. A means for detecting a current speed of a web drawn from a web roll and a means for detecting a current diameter of the web roll, wherein the main switch is turned off to determine the current speed and the current diameter of the both detecting means. An emergency stop device equipped with a tension controller that outputs an emergency brake command to the brake of the web roll. 2. The speed of the web drawn from the web roll and the diameter of the web roll are detected, and when the main switch is turned off, an emergency braking command based on the speed and the diameter at that time is used to control the web roll. Apply an emergency stop method such as applying a brake. 3. A dancer roller that descends due to the slack of the web is provided between the web roll and an in-feed roller that draws the web from the web roll, and further, the current speed of the web drawn from the web roll is detected. Means and means for detecting the current diameter of the web roll, and when the main switch is turned off, an emergency braking command is output to the brake of the web roll based on the current speed and the current diameter by both detection means, and the web An emergency stop device equipped with a tension controller for changing the emergency brake command to a start level command when the dancer roller descends due to the slack of the web based on the emergency brake of the roll. 4. The speed of the web pulled out from the web roll and the diameter of the web roll are detected, and when the main switch is turned off, an emergency braking command based on the speed and the diameter at that time is used to control the web roll. An emergency stop method in which the emergency brake command is changed to a start level command when the brake is applied and then the dancer roller that descends based on the slack of the web returns to the rising position.