JP2636536B2 - Strip tension controller for continuous processing line - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for controlling strip tension in a continuous strip metal (hereinafter referred to as "strip") processing line provided with a looper such as a loop car or a loop tower.

[0002]

2. Description of the Related Art In general, in a continuous processing line for pickling or heat-treating a strip, the end of the next strip is connected to the rear end of one strip by welding or the like, and a plurality of strips are sequentially connected. The processing is performed. By the way, in a processing apparatus that performs pickling or heat treatment in such a continuous processing line, it is necessary to maintain a constant strip tension in order to make deformations such as thermal expansion and width reduction uniform . By the way , the strips must be temporarily stopped on the inlet side of the processing apparatus to sequentially weld and connect the strips, and on the outlet side of the processing apparatus to cut the strips into fixed lengths.
For this reason, a looper such as a loop car or a loop tower is installed as a buffer for storing a strip length corresponding to the strip length conveyed during the time required for connection and cutting. The looper is moved in the direction of increasing the amount of storage of the strip or in the direction of decreasing the amount of storage of the strip depending on the situation on the upstream side or the downstream side . But like this
In order to maintain a constant strip tension even while the looper is moving, a configuration in which a looper driving torque or a driving current is controlled by using a tension meter is generally adopted, and the input of the processing device is generally performed. welding at the side or the exit side, after the completion of the cutting operation, looper position to adjust the entry side or exit side of the bridle roll speed it is necessary to return the looper to the original position to return the looper in place A control device is installed.

FIG. 5A is a block diagram showing a tension control system using a looper in a conventional apparatus, and FIG. 5B is a block diagram showing a position control system. In the tension control system shown in FIG. 5 (a), the tension deviation between the reference of the strip tension and the tension feedback value from a tension meter or the like is input to the proportional-integral element 13, and the tension reference is determined by the tension / current conversion circuit 12
, And adds the output of the proportional-integral element 13 and the output of the compensation circuit 15 for mechanical loss, inertia, etc.
The current is input to the current control device 14 of the looper drive motor as a current reference, and the looper drive motor 6 is controlled.

On the other hand, in FIG. 5B , the position deviation between the position reference of the looper and the position feedback value is input to the position control device 21 and the switching control unit 30. The output of the position control device 21 is input to the speed control device 23 of the entrance bridle roll via the relay contact 22, and controls the drive motor 7 of the entrance bridle roll. The relay contact 22 is a switching control unit.
Based on the output of 30, the looper is turned on when the position deviation of the looper is outside a predetermined range, and is turned off when the position deviation is within the predetermined range.

[0005]

However, in order to increase the storage amount of the strip in the looper and to secure the working time on the entrance side or the exit side, the length of the looper is increased or the number of strands is increased. there is a need, but usually from constraints on the space is often to increase the number of strands. However, in this case, the looper equipment is large, the weight is large, and its inertia and friction are inevitably increased. In such a facility, once the looper is stopped, a large torque is required for the looper drive motor 6 when it starts to move due to its large inertia and static friction resistance.

Therefore, when the torque of the looper drive motor is slightly changed, the looper does not move while stopped, and the strip tension does not change. As a result, the proportional-integral output is saturated. There is a risk that excessive (or under) tension will occur in the strip due to inertia. As a countermeasure, a speed control loop is provided as a minor loop of a current control system for the looper drive motor in order to prevent a transient tension fluctuation caused by a difference between static friction resistance and dynamic friction resistance at the time of starting the looper. There has been proposed a technique for correcting a difference in strip speed between the entrance side and the exit side in a speed control loop (JP-A-55-77919).

[0007] However, in this device, the tension fluctuation at the time of starting the looper can be suppressed, but the tension control at the time of stopping the looper is only the current control by the looper drive motor, so that accurate tension control cannot be performed due to the influence of the static frictional resistance. When the looper is slightly moved, the tension control and the position control interfere with each other, and the looper position and the strip tension fluctuate periodically. There was a problem.

The present invention has been made in view of the above circumstances, and an object of the present invention is to stabilize the strip tension and maintain a reference even when the looper is stopped as well as during the movement of the looper. It is an object of the present invention to provide a strip tension control device for a continuous processing line which can be controlled in a continuous manner.

[0009]

SUMMARY OF THE INVENTION A strip tension controller for a continuous processing line according to the present invention comprises a loop tensioner capable of moving in a direction to increase and decrease a storage amount of a strip. A detector for detecting the speed and position of the looper in the control device;
A control system for controlling the torque of the looper drive motor in response to the tension deviation between the strip tension reference and tension detection value, the strip conveying roll drive motor at the entry side or delivery side of the looper according to the <br/> tension deviation A control system for controlling the speed, a control system for controlling the speed of the strip-conveying-roller drive motor in accordance with the positional deviation between the looper position reference and the position detection value, and a detection system for detecting the speed and position of the looper
The looper is moving or stopped based on the detector detection value
And whether the positional deviation exceeds a predetermined value.
If the position deviation of the looper exceeds a predetermined value,
Control system for controlling torque of looper drive motor and strike
Looper that controls the speed of the lip transport roll drive motor
Operate the position control system respectively, while the position deviation is within the specified value
And if the looper is moving, the tension deviation
Control system to control the torque of the looper drive motor according to
And if the position deviation is within the specified value and the
If the lock is stopped, the storage
Activates the control system that controls the speed of the
And switching means for causing the operation to be performed.

[0010]

According to the apparatus of the present invention, it is possible to precisely control the tension not only in the state where the looper is stopped but also in the transition state where the looper is shifted from the stopped state to the moving state.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below with reference to the drawings showing the embodiments. FIG. 1 is a schematic diagram showing a strip tension control device for a continuous processing line according to the present invention.
Denotes a strip, 1 denotes a processing device such as an pickling tank or an annealing furnace, 2 denotes an inlet bridle roll, 3 denotes an outlet bridle roll, 4 denotes a looper, and 10 denotes a strip tension control device. As shown by the arrow, the strip S is supplied from the upstream side to the processing device 1 through the entrance bridle roll 2, the looper 4, and the bridle roll 5, and after being subjected to a predetermined process, passes through the exit bridle roll 3, Thereafter, it is sent to a shear or the like via a looper (not shown).

The looper 4 is composed of a plurality of fixed rolls 4a, a loop car 4c having a plurality of rolls 4b, and the like. The strip passing through the entrance bridle roll 2 is formed of the roll 4b of the loop car 4c and the fixed roll 4a. Wrapped around,
After the loop, it enters the bridle roll 5. A wire 4e is stretched between the loop car 4c and the drum 4d, and a looper drive motor 6 is connected to the drum 4d.

Reference numeral 7 denotes a drive motor for the entrance bridle roll 2, 8 a strip tension detector, and 9 a looper 4 (specifically, a loop car 4c) comprising a pulse generator attached to the looper drive motor 6. It is a speed and position detector.

The strip tension control device 10 fetches the detection signals of the tension detector 8, the speed and position detector 9, and outputs them to a separately inputted looper tension reference (tension detector 8).
The looper drive motor 6 and the entrance bridle roll drive motor 7 are controlled based on a tension reference at the installation position) and a looper position reference.

FIG. 2 is a block diagram showing a tension and position control system provided in the strip tension controller 10. As shown in FIG. A tension deviation between the looper tension reference and the tension feedback value detected by the tension detector 8 is input to the proportional integral element 13 and the proportional element 18 through the contacts 11 and 17. The tension reference is input to a tension / current conversion circuit 12 and converted into a current value, and this current value, the output of the proportional-integral element 13,
The output of the compensation circuit 15 for mechanical loss, inertia, and the like is added, and the sum is input to the current control device 14 as a current reference to drive and control the looper drive motor 6. Reference numeral 16 denotes an integration amount reset circuit which gradually approaches the integration amount of the proportional integration element 13 to zero.

On the other hand, the position deviation between the looper position reference and the position feedback value detected by the speed / position detector 9 is input to the position control device 21 and the switching control unit 30. The output of the position control device 21 is added to the output of the proportional element 18 via the contact 22 and is input to the speed control device 23 to control the drive motor 7 of the entrance bridle roll 2.

The switching controller 30 receives the position deviation and speed between the position reference and the position feedback value, and the looper speed feedback value detected by the position detector 9, and based on these inputs, the contacts 11, 17, and 22. Is controlled to switch the control mode. The control mode switching pattern is as shown in Table 1.

[0018]

[Table 1]

As is clear from Table 1, when the positional deviation between the position reference and the position feedback value exceeds a certain value, the contacts 11, 22 are closed and the contact 17 is opened, so that the looper 4 stops as in the conventional case. Tension control and position control are performed irrespective of whether they are moving or moving, torque control is performed on the looper drive motor 6 in accordance with the tension deviation between the tension reference and the tension feedback value, and the entrance bridle is controlled. Speed control is performed on the drive motor 7 of the roll 2 in accordance with the position deviation between the looper position reference and the position feedback value. When the position deviation is within a certain value, the contact point 22 opens, and the position control of the looper is not performed.

On the other hand, when the position deviation is within a certain value and the looper is stopped, the contacts 11, 22 are opened and the contact 17 is closed, so that only the output of the proportional element 18 is sent to the speed controller 23. The speed is controlled according to the tension deviation between the tension reference and the tension feedback value for the drive motor 7 of the input side bridle roll 2 that is input, and the strip tension is controlled. In other cases, that is, during the movement of the looper , the contact point 11 is closed and the contacts 17 and 22 are opened, so that the looper drive motor
6, the strip tension is controlled. When the contact 17 is closed and the contact 11 is opened, the differential amount reset circuit 16 operates, the integration amount of the proportional integration element 13 gradually approaches 0, and when the contact 11 is closed, that is, the looper operates again. Care is taken so that the strip tension does not change abruptly when it starts.

As described above, in the present invention, even when the looper is stopped, when the positional deviation of the looper is within a predetermined value, the contact 17 is closed to drive the entrance-side bridle roll 2. Due to the speed control on the motor 7, the position deviation of the looper is not
Is closed and the position control system is operating, the contact 11 is closed, the strip tension is controlled by the torque control on the looper drive motor 6, and the strip tension can be maintained stably.

Next, the results of a comparison test between the device of the present invention and the conventional device are shown. FIG. 3 shows the results for the apparatus of the present invention shown in FIGS. 1 and 2, and FIG. 4 shows the results for the conventional apparatus shown in FIG. 3 and 4, (a) is the looper position, (b) is the looper speed, (c) is the entrance bridle roll speed, (d) is the looper current reference (or current value), (e)
Indicates a change in strip tension. According to the comparison between FIGS. 3 and 4, when the looper is stopped and immediately after the start of the looper, around points g and h, the conventional device lacks tension (point j).
Alternatively, it can be seen that while the excessive tension (k point) is generated, the tension fluctuation is greatly reduced in the apparatus of the present invention.

In the above-described embodiment, the tension control by the looper 4 disposed on the input side of the processing apparatus 1 has been described. However, the drive motor of the looper 4 disposed on the output side of the processing apparatus 1 and the tension motor disposed on the output side thereof. Needless to say, the present invention is also applicable to the bridle roll drive motor provided. In the above-described embodiment, the configuration applied to the looper drive motor 6 and the entrance bridle roll drive motor 7 has been described. However, the present invention is not limited to this, and the looper drive motor 6 and the strip transport roll drive motor in the continuous processing line may be used. May be applied.

[0024]

As described above, according to the apparatus of the present invention ,
If the position deviation of the par exceeds the specified value,
Control system for controlling torque of dynamic motor and strip transfer
Looper position control system that controls the speed of the roll drive motor
Has a large effect on the strip tension.
The position of the looper can be controlled without giving
If the position deviation of the looper is within the specified value,
If moving, looper drive according to the tension deviation
Activates the control system that controls the motor torque, and
Looper stops when par deviation is within the specified value
If there is a
Operating the control system that controls the speed of the motor
It has replacement means, so when the looper is stopped
Tension control considering the effect of static friction resistance
-Even when the robot is moving slightly, tension control and position control
Without interference, looper position, strip tension
Can be prevented from occurring.

[Brief description of the drawings]

FIG. 1 is a schematic view of the device of the present invention.

FIG. 2 is a block diagram of a control system in the apparatus of the present invention.

FIG. 3 is a graph showing test results of the device of the present invention.

FIG. 4 is a graph showing test results of a conventional device.

FIG. 5 is a block diagram showing a control system of the conventional device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Processing apparatus 2 Inlet bridle roll 3 Outlet bridle roll 4 Looper 5 Bridle roll 6 Looper drive motor 7 Inlet bridle roll drive motor 8 Tension detector 9 Speed and position detector 12 Tension / current conversion circuit 13 Proportional integration element 14 Current controller 21 Position controller 22 Relay contact 23 Speed controller 30 Switching controller

Claims (1)

(57) [Claims] 1. A strip tension control device for a continuous processing line having a looper movable in a direction to increase and decrease a storage amount of a strip, a detector for detecting a speed and a position of the looper, and a strip tension. a control system for controlling the torque of the looper drive motor in response to the tension deviation between the reference and the tension detected value, control system for controlling the speed of the strip conveying roll drive motor at the entry side or delivery side of the looper in accordance with the tension deviation When the control system and the Lou controlling the speed of the strip conveying roll drive motor in accordance with the position deviation between the position detection value and the looper position reference
Based on the values detected by the detector that detects the speed and position of the par.
Is moving or stopped, and the position deviation is
It is determined whether each value exceeds a predetermined value.
If the difference exceeds a predetermined value, the looper drive motor
Control system for controlling the torque
Operate the looper position control system that controls the speed of the motive.
On the other hand, if the position deviation is within the
If it is moving, the looper drive power is
Activate the control system that controls the torque of the motive, and
When the difference is within the specified value and the looper is stopped
In accordance with the tension deviation, the strip transport roll drive
Switching means for operating a control system for controlling the speed of the machine;
Strip tension control device of the continuous processing line, characterized in that it comprises a.