JPH04246133A - Apparatus for stabilizing tension in continuous treating line - Google Patents

Abstract

PURPOSE:To restrain variation of tension in a strip in an annealing furnace and to obtain stable operation in a line, in the continuous annealing line, etc. CONSTITUTION:When the variation of tensions in looper 8 at outlet side of the furnace propagates in the furnace 6, at the time of sensing this with control mechanism 3 for roll working through a detector 2 at outlet side of the furnace, a damper roll 1 is immediately worked, and by making this absorbed with damper action of this roll 1, the propagation of the above variation of tension in the furnace is prevented. Further, at the time of sensing the variation of tension developed in the looper 8 at outlet side with speed regulation mechanism 5 through a detector 4 at inlet side of the looper, by immediately controlling speed of a bridle roll 7b at outlet side of the looper 8, the variation of tension in the outlet side looper 8 is restrained. The variation of tension of the strip in the annealing furnace in the continuous annealing line, etc., is restrained, and meandering in the furnace and drawing in the furnace are restrained, and stable operation in the line can be executed.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an annealing furnace and a tension stabilizing device in a continuous metal strip processing line provided with a looper near the furnace.

0002

[Prior Art] Continuous processing lines that continuously apply hot-dip plating, electroplating, painting, etc. to metal bands such as strips, including continuous annealing lines, use annealing furnaces that continuously anneal the metal bands midway through the line. There are some that have the following. In such a line, stable running of the metal strip in the annealing furnace is essential for stable line operation.

0003

[Problems to be solved by the invention] In a line equipped with such an annealing furnace, one of the causes is the tension fluctuation of the furnace outlet looper that occurs due to the following reasons (1) and (2). propagates into the annealing furnace, causing meandering and throttling in the furnace due to fluctuations in the tension in the furnace, resulting in the stable operation of the line being inhibited.

(1) Conventionally, when the looper carriage goes up and down, there is a mechanical loss inside the looper (generally, this is a mechanical loss in the looper that occurs due to frictional force when the looper carriage goes up and down, but even when the carriage stops, the carriage moves up and down. Since there is slight movement in the direction, mechanical loss will occur in this case as well)
In order to compensate for this, a mechanical loss compensation current was added to the looper drive motor. However, when the furnace exit speed and the furnace speed were synchronized, the mechanical loss amount became uncontrollable, causing tension fluctuations in the exit looper.

(2) When the roll in the looper is idle during acceleration/deceleration on the exit side of the furnace, the acceleration/deceleration torque of the roll appears as a fluctuation in the tension of the looper. As a countermeasure to this problem, a configuration in which the roll in the looper is driven has been adopted, but it has not been possible to completely prevent tension fluctuations.

[0006] Therefore, in order to prevent the tension fluctuations generated in the exit looper from propagating into the annealing furnace, a vertical torque motor-driven dancer roll has been adopted. However, since it is vertical, a counterweight is required, and the drive device is heavy and has large inertia, so it is not possible to completely prevent tension fluctuations from propagating into the furnace, and the torque motor drive system has a large mechanical loss, making it difficult to control. The problem was that it was bad.

The present invention was devised in view of the above-mentioned problems of the prior art, and includes a new configuration for preventing tension fluctuations in the furnace outlet side looper from propagating inside the furnace, and a structure for preventing tension fluctuations in the looper. It is an object of the present invention to provide a continuous processing line tension stabilizing device.

[0008]

[Means for Solving the Problems] Therefore, the tension stabilizing device of the present invention is provided between the annealing furnace and the exit looper as a structure for preventing the tension fluctuation of the furnace exit looper from propagating inside the furnace, and is provided between the annealing furnace and the exit looper. A winding gas fluid damper roll, a furnace exit side detector installed on the furnace exit side to detect the tension of the metal band, and a fluctuation in the tension of the metal band detected by the furnace exit side detector. At times, a roll operation control mechanism is provided to control the operation of the damper roll and prevent tension fluctuations from propagating within the furnace, and as a structure for preventing tension fluctuations within the looper, the tension of the metal band on the input side of the looper is detected. and a speed adjustment mechanism that controls the speed of the bridle roll on the looper exit side to suppress fluctuations in looper tension when the tension of the metal strip detected by the looper entrance detector changes. has been established.

[0009]

[Function] When there is a tension fluctuation in the exit side looper, the metal strip tension detected by the furnace exit side detector also changes, and as soon as the roll operation control mechanism senses this fluctuation, the mechanism immediately controls the gas fluid damper. The pressure of the gas fluid in the roll is adjusted to absorb this tension fluctuation just before it propagates into the furnace, and the tension is adjusted to a predetermined tension.

On the other hand, such a structure for preventing tension fluctuations from propagating in the furnace only copes with temporary tension fluctuations, and is insufficient to prevent continuous tension fluctuations. Therefore, the tension of the metal band on the looper input side is detected by the looper input side detector,
The speed adjustment mechanism senses tension fluctuations occurring within the looper. Then, the mechanism controls the speed of the bridle roll on the exit side of the looper to suppress fluctuations in the tension of the looper and stabilize the tension of the entire line.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows an embodiment of a line tension stabilizing device according to the present invention, which is provided between the exit side of an annealing furnace 6 and a tension reel 9 in a continuous annealing line for strips X.

An in-furnace propagation prevention structure is provided at the outlet side of the annealing furnace 6 and at a position before and after the outlet looper 8 installed immediately after the annealing furnace 6 to prevent tension fluctuations generated in the looper 8 from propagating into the furnace 6. The present embodiment is provided with a tension variation prevention structure that prevents tension variation within the looper 8.

That is, a gas fluid damper roll 1 wound around the strip X on the exit side of the furnace 6, and a furnace exit side detector 2 consisting of a tension meter also provided on the exit side of the furnace 6 and detecting the tension of the strip X. The roll operation control mechanism 3 that controls the operation of each damper roll 1, the configuration of which is shown in FIG. The looper entrance side detector 4 and the speed adjustment mechanism 5 that controls the speed of the fourth bridle roll 7b on the exit side of the looper 8 are configured to prevent tension fluctuations and are applied to the continuous annealing line.

As the damper roll 1, a horizontal lightweight pneumatic type having a structure as shown in FIG. 3 is used. That is, the frame 11 holding the roll 10 on which the strip
The guide rail 13a is expanded and contracted by the cylinder rod 2b.
, 13b, and by sliding the frame 11 in response to the tension fluctuation of the strip X, the strip X generated due to this tension fluctuation can be removed.
The air spring acts as a damper to absorb and attenuate slack and tension.

The roll operation control mechanism 3 also inputs the detected tension value of the strip a comparator 30 for calculating the difference, a pressure converter 31 for converting the deviation into pressure, a pressure monitor 32 for detecting the air pressure of the air cylinders 12a and 12b of the damper roll 1,
The detected value of the monitor 32 is inputted, and the deviation from the pressure set value of the damper roll 1 outputted from the pressure converter 31 is determined to control the servo valve 33 which adjusts the air pressure supplied to the air cylinders 12a, 12b. It has a pressure controller 34 for controlling. In this embodiment, a position sensor (not shown) is attached to the frame 11 of the damper roll 1, and the third bridle roll 7a located between the outlet looper 8 and the annealing furnace 6
The detected position value is input to the constant speed control device 70 of the third bridle roll 7.
By controlling the speed of the damper roll 1, the position of the damper roll 1 is controlled so that the damper roll 1 is normally positioned approximately at the center of the guide rails 13a and 13b.

On the other hand, the speed adjustment mechanism 5 controls the speed of the strip X on the input side of the looper 8 detected by the looper input side detector 4.
Input the detected tension value, find the difference from the preset looper inlet tension setting value, convert the deviation to a speed difference,
It is composed of an arithmetic circuit 50 that inputs the converted value to the constant speed control device (ASR) 71 of the fourth bridle roll 7b on the output side of the looper 8, and the constant speed that inputs the speed converted value from this circuit 50 A control device 71 controls the speed of the fourth bridle roll 7b.

In this embodiment, the tension is set by the constant current circuit 80 of the output side looper 8, and the looper position is controlled by the speeds of the input and output sides of the looper.

The operation of this embodiment having the above configuration will be explained.

If there is a sudden change in the tension of the strip
0 immediately senses this and communicates it to the pressure controller 34 via the pressure transducer 31. Then, the pressure controller 34 controls the servo valve 33 in response to this fluctuation, and the air cylinders 12a, 12 of the damper roll 1
The air in b is compressed and expanded, and the slack and tension in the strip X caused by tension fluctuations generated and propagated in the exit looper 8 are absorbed and attenuated by the damper action of the damper roll 1. Therefore, the tension fluctuation of the strip X generated in the outlet looper 8 does not propagate into the annealing furnace 6.

Furthermore, in the exit side looper 8, when the looper carriage is stationary (when the exit speed and the furnace speed are approximately constant), the looper inlet tension increases or decreases due to the influence of mechanical loss within the looper. Furthermore, when the looper carriage is moving (when the exit side accelerates or decelerates), the tension at the looper inlet may increase or decrease due to the acceleration/deceleration torque of the roll inside the looper or due to fluctuations in mechanical loss inside the looper. do. Such tension fluctuations are detected by the arithmetic circuit 50 of the speed adjustment mechanism 5 via the looper entrance side detector 4, and the deviation from the looper tension setting value is detected by the arithmetic circuit 50.
is input to the constant speed control device 71 of the fourth bridle roll 7b to change the speed of the fourth bridle roll 7b and control the slack and tension of the strip X in the looper 8 to a predetermined tension. As a result, tension fluctuations in the output looper 8 are eliminated.

[0022]

[Effects of the Invention] According to the apparatus of the present invention described in detail above, tension fluctuations occurring in the furnace exit looper, which is one of the causes of tension fluctuations in the annealing furnace in the line, are prevented from propagating into the furnace. It is also possible to prevent tension fluctuations in the outlet looper, which has a remarkable effect on preventing tension fluctuations in the furnace, suppressing the occurrence of meandering and throttling in the furnace, and improving line performance. Stable operation becomes possible.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing a line configuration on the furnace exit side of a continuous annealing line to which an apparatus according to an embodiment of the present invention is applied.

FIG. 2 is an explanatory diagram showing the configuration of a roll operation control mechanism in this embodiment.

FIG. 3 is a perspective view showing the configuration of a gas fluid damper roll used in this example.

[Explanation of symbols] 1 Gas fluid damper roll 2 Furnace exit side detector 3 Roll operation control mechanism 4 Looper entrance side detector 5 Speed adjustment mechanism 6 Annealing furnace 7a, 7b Bridle roll 8 Furnace outlet side looper X Strip

Claims (1)

[Claims] Claim 1: A gas fluid damper roll provided between an annealing furnace and an exit side looper of a continuous processing line and wound around a metal band, and a furnace provided on the furnace exit side to detect the tension of the metal band. an exit side detector; and a roll operation control mechanism that controls the operation of the damper roll to prevent tension fluctuations from propagating within the furnace when a fluctuation occurs in the tension of the metal strip detected by the furnace exit side detector. and a looper entry side detector that detects the tension of the metal strip on the looper entry side, and when a fluctuation occurs in the tension of the metal strip detected by this looper entry side detector, the speed of the bridle roll on the looper exit side is adjusted. A continuous processing line tension stabilizing device characterized by having a speed adjustment mechanism that controls and suppresses fluctuations in looper tension.