JPS61286023A - Tension control device of band-shaped body in looper - Google Patents

Abstract

PURPOSE:To improve the quality of a band-shaped body by providing a linear body tension detecting means and inputting its detected value to a tension control device, and subsequently, bringing a motor of a winding drum to a driving control, based on a comparison with a reference value. CONSTITUTION:A tension detecting means 11a is provided on a linear body rope 6 of an adjacent position of a winding drum 7. The tension detecting means 11a has a sensor roller 14a and a load cell 15a, and outputs a tension detecting signal corresponding to only a tension of the rope 6. This tension detecting signal is inputted to an adder 16, and an adding signal SA is inputted to a tension control circuit 17. To the control circuit 17, a reference tension signal SK is supplied in advance from a reference value setting circuit 18, and a tension control signal CT for setting a difference of both of them to zero is outputted. According to this method, an armature current of a driving motor 23 is controlled and a tension of the rope 6 is maintained correctly. Accordingly, a tension of a strip 5 is maintained so as to be constant, and its quality is improved.

Description

[Detailed Description of the Invention] C. Industrial Application Field] The present invention is directed to a belt-shaped body such as a metal strip provided on the inlet or outlet side of a continuous pickling line, cold rolling process line (surface treatment), etc. The present invention relates to a tension control device for a band-shaped body in a looper that controls the tension of a band-shaped body stored in a louver to an appropriate value.

[Conventional technology]

In general, a belt tension control device in a looper uses a DC motor to drive a winding drum that winds a moving roll in the looper via a loop car or carriage and lobes connected to the looper. By adjusting the slave current, the tension of the metal strip inserted into the louver is controlled. Tension control in this case is performed, for example, by accelerating or decelerating the moving speed of the loop car or carriage in accordance with the processing conditions, but during such acceleration or deceleration, there is a loss of torque in the DC motor. There is a problem in that the speed fluctuation causes mechanical vibration of the metal strip and the rope, which causes the tension of the metal strip to fluctuate.

In order to solve this problem, the following three tension control methods have been proposed.

■ Detect the speed difference between the metal strip speed Vf on the entrance side of the louver and the metal strip speed vb on the exit side, differentiate the speed difference, estimate the acceleration/deceleration α of a loop car, and calculate the acceleration/deceleration based on this acceleration/deceleration α. Torque loss TA required for
A tension control method (first conventional example) in which the armature current of a DC motor is adjusted accordingly.

■ Calculate the rotational speed of the DC motor that moves the loop car based on the speed difference (Vf - Vb) between the metal strip speed Vf on the entrance side of the louver and the speed vb of the metal strip on the exit side, and use the calculated value as the actually measured DC A tension control method (second conventional example) that compares the rotational speed of an electric motor and corrects the armature current of a DC motor to suppress mechanical system vibration when the difference between the two exceeds an allowable setting range.

■ A tension control method (third conventional example) in which a load cell for detecting the tension of a metal strip is provided on a fixed roll in the louver, and the tension detection value of this load cell is used as a control signal for the armature current of a DC motor.

[Problem that the invention seeks to solve]

However, in the first conventional example described above, since the torque loss Ta required for acceleration and deceleration of the loop car is predicted, it is difficult to accurately calculate the value of the armature current to cancel the torque loss TA. Moreover, there is the problem that the timing of acceleration/deceleration compensation is delayed, and there is also the serious problem of being completely powerless against vibrations in the mechanical system, and it is impossible to completely prevent tension fluctuations in the metal strip. It was impossible.

In addition, in the second conventional example, although the fluctuation in the tension of the metal strip is somewhat reduced, the tension of the metal strip inside the louver is indirectly controlled based on the speed difference between the metal strip on the entrance and exit sides of the louver. However, there was still a problem that tension fluctuations still existed.

Furthermore, in the third conventional example, since there is a large phase lag between the load cell that detects the tension of the metal strip and the winding drum driven by the DC motor, the tension of the metal strip at high frequencies The problem was that it could not deal with fluctuations.

As described above, in each of the conventional examples described above, it has been impossible to effectively prevent fluctuations in the tension of the metal strip when accelerating or decelerating the moving speed of the loop car or carriage that moves the moving roll in the louver.

Therefore, the present invention detects the moving speed of a loop car or carriage that moves a moving roll by detecting the tension of a linear body provided between this and a winding drum,
An object of the present invention is to provide a tension control device for a strip in a louver that can prevent tension fluctuations in the strip within the louver by controlling the drive current of a DC motor that drives a winding drum based on this. It is said that

[Means for solving problems]

In order to achieve the above object, the present invention alternately spans a band-like body between a required number of fixed rolls and a required number of moving rolls, and connects a moving body that moves the moving rolls via a linear body. The looper is configured to control the tension of the strip by being pulled by a winding drum, and the looper includes a wire tension detecting means disposed in the vicinity of the winding drum of the wire; a tension control means for outputting a tension control signal by comparing a tension detection signal of the means with a predetermined reference signal; and controlling a drive current of the electric motor for driving the winding drum based on the tension control signal from the tension control means. The present invention is characterized by comprising a drive current control means.

[Effect]

In this invention, the tension of the linear body stretched between the loop car or carriage that moves the moving roll of the looper and the winding drum is detected by a wire condition tension detector at a position near the winding drum. , a drive electric motor that supplies the detected value to the tension control means, compares it with a reference value, forms a tension control signal that makes the difference value zero, and drives the winding drum from the drive current control means based on the tension control signal. By controlling the drive current, the tension of the linear body near the winding drum can be maintained at a predetermined value at all times, and fluctuations in the tension of the strip within the louver during acceleration and deceleration can be reliably prevented.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is a schematic diagram showing an embodiment of the present invention.

In the figure, 1 is a fixed roll rotatably pivoted to a fixed part;
2a and 2b are moving rolls, which constitute a looping pit 3.

Each of the moving rolls 2a and 2b is rotatably attached to a mounting frame 4a formed on a loop car 4 as a moving body, and is moved forward and backward with respect to the fixed roll 1 as the loop car 4 moves.

Then, the metal strip 5 as a band-shaped body is transported from the input side of the looping pit 3 while alternately wrapping around the moving roll 2a, the fixed roll 1, and the moving roll 2b, and is sent out from the exit side.

On the other hand, the loop car 4 is connected to the winding drum 7 via a row 16 as a linear body, and moves forward and backward with respect to the fixed roll 1 according to the rotational direction of the winding drum 7. In this case, as shown in FIG. 2, one end 6a of the rope 6 is fixed to a fixed part, and the other end 6b is connected to a winding drum via guide rollers 8a and 8b pivotally connected to the rear end of the loop car 4. The loop car 4 is wound around a winding drum 7 and fixed to a fixed portion via guide rollers 9a and 9b pivotally attached to the front end of the loop car 4.

Further, a lifting prevention presser roll IO is connected to the outer peripheral surface of the winding drum 7, and this roll 10 prevents the rope 6 from lifting at the winding drum position.

Further, tension detection means 11a and 11b are provided on the ropes 6c and 6d near the winding drum 7. Each of the tension detection means 11a and 11b includes a rope 6c;
vibrating presser rolls 12a, 12b arranged at a predetermined interval so as to restrict upward movement of 6d;
12c, 12d, and a positioning roller 13a disposed outside these for regulating movement in the left and right direction.
13b, 13c, and 13d, which prevent mechanical vibration of the rope 6 and displacement of the winding position onto the winding drum 7.

The tension detecting means 11a and 11b also operate between the vibrating presser rollers 12a and 12b and between the vibrating presser rollers 12c and 12d.
It has sensor rollers 14a, 14b that roll into contact with the ropes 6c, 6d between them from below, and load cells 15a, 15b attached to these as tension detectors, and the tension of the ropes 6c, 6d is measured from these load cells 15a, 15b. A tension detection signal corresponding to only the tension is output.

These tension detection signals are supplied to an adder 16 and added, and the added signal SA is input to a tension control circuit 17. This tension control circuit 17 is supplied with a reference tension signal SK from a reference value setting circuit 18, and the tension that makes the difference between the two zero! Outputs IJ# signal CT.

This tension control signal CT is input to a current control circuit 19, and this current control device 19 adds or subtracts the tension control signal CT to a reference current signal sr from a reference current value setting circuit 20. armature current A
A current control signal CI for constant current control of the armature current DA is output based on a current feedback signal from a current detector 22 that detects I.

This current control signal CI is input to the motor drive circuit 21, and the armature current AI corresponding to the current control signal cr is transmitted from the motor drive circuit 21 to the motor 23 of the motor 23 for driving the winding drum 7, which is a DC motor. Output to child.

Next, the operation of the above embodiment will be explained. Now, the metal strip 5 is inserted into the looping pit 3, alternately covering the moving rolls 2a, 2b and the fixed roll 1, and being sent out to the outside of the looping bit 3. Assume that the speeds are equal. At this time, the rotational position of the winding drum 7 is at an appropriate position, the loop car 4 is pulled by a predetermined traction force via the row 16, and a predetermined tension is applied to the metal strip 5 by the moving rolls 2a and 2b. Then, the tension detection means 11a and the load cell 15a of llb.

The added tension detection signal SA obtained by adding the tension detection signals outputted from the adder 15b by the adder 16 becomes approximately equal to the reference tension setting signal SK outputted from the reference tension setting circuit 17. Therefore, the tension control circuit 17 outputs a tension control signal CT of approximately zero, and the current control circuit 19 outputs a current control signal CI that maintains the armature current value up to now, and the motor is driven accordingly. A predetermined value of armature current AI from circuit 21
is supplied to the drive motor 23. Therefore, the winding drum 7 is driven to maintain a predetermined torque, and the tension of the ropes 6c and 6d is also maintained at an appropriate value.

In this state, for example, if the exit speed of the metal strip 5 decreases relative to the entrance speed of the looping pit 3, the tension of the metal strip 5 in the looping bit 3 will decrease, causing the loop car 4 and the winding drum to decrease. The tension of the ropes 6c and 6d between the ropes 7 also tends to decrease. In this way, when the rope tension starts to decrease, the values of the detection signals of the tension detection means 11a and the load cells 15a, 15b of the workpiece 1b will decrease, so the value of the added tension signal SA output from the adder 16 will decrease. also decreases, and the reference tension setting signal SK
It becomes less than O value. In response, the tension control circuit 17 outputs a tension control signal CT having, for example, a positive predetermined value to restore the tension of the rope 6 to the proper state, and this is supplied to the current control circuit 19. The armature current A is increased by the amount ΔAl corresponding to the tension control signal CTO value.
A current control signal CI that increases I is output. Therefore, from the motor drive circuit 21, the previous armature current AIi
The armature current AII is the sum of ΔAl. .

is output to the drive motor 23. Accordingly, the winding torque of the winding drum 7 is increased to maintain the ropes 6c, 6d at appropriate tension. As a result, the tension in the metal strip 5 is maintained at an appropriate value.

Thereafter, when the exit speed of the looping bit 3 of the metal strip 5 returns to the normal speed, the tension of the metal strip 5 in the looping bit 3 tends to increase, contrary to the above, and the load cells of the tension detection means 11a and Ilb 15
Since the tension detection signals of a and 15b will increase,
The tension control circuit 17 outputs a tension control signal CT that decreases the lobe tension, and in response, the current control circuit 19 outputs a current control signal CI that decreases the armature current AI. The value of current AI is reduced. Therefore, the torque of the winding drum 7 is reduced, the tension of the ropes 6c and 6d is reduced, and the tension of the metal strip 5 is maintained at an appropriate value.

In this way, the ropes 6c, 6 near the winding drum 7
The tension of the ropes 6c and 6d is detected by the tension detection means 11a and 11b, and based on this, the armature current of the drive motor 23 of the winding drum 7 is controlled to maintain the tension of the ropes 6c and 6d in an appropriate state. Since the responsiveness of the strip 5 to tension fluctuations can be improved, the metal strip 5
It is possible to reliably suppress fluctuations in the tension of the metal strip 5, prevent galling of the side edges of the metal strip 5 due to meandering of the loop car 4, etc. due to fluctuations in the tension of the metal strip 5, and maintain the tension of the metal strip 5 constant. Therefore, the quality of the metal strip 5 can be improved.

In addition, in the above embodiment, the looping pit 3 is 1
Although a case has been described in which the roll is composed of one fixed roll 1 and two moving rolls 2a and 2b, the number of fixed rolls and moving rolls can be arbitrarily selected.

In addition, in the above embodiment, the case where the moving roll 2at2b is supported by the loop car 4 has been described, but
Of course, a carriage can be used instead of this.

Further, in the above embodiment, the case where the loop car 4 and the winding drum 7 are connected by a linear body made of the rope 6 has been described, but the connection may be made by using another linear body such as a wire. good.

Furthermore, in the embodiment described above, two sets of tension detection means for detecting the tension of the rope 6 between the loop car 4 and the winding drum 7 are provided, but one of them and the adder 15 may be omitted. Also,
The tension detector is not limited to a load cell, and a pressure detector such as a differential transformer can be used.

〔Effect of the invention〕

As explained above, according to the present invention, the tension of the linear body at a position near the winding drum that generates a traction force to the loop car or carriage via the linear body is detected by the linear body tension detection means. The detected tension value is supplied to the tension control device and compared with a reference value to obtain a tension control signal that makes the difference between the two zero, and based on this tension control signal, the drive motor that rotates the winding drum is driven. I tried to control it, so
Tension fluctuations in the linear body can be suppressed with high responsiveness, and this makes it possible to effectively absorb tension fluctuations in the strip passed between the fixed roll and the moving roll. It is possible to prevent galling of the side end of the strip due to meandering of the loop car due to fluctuations, etc., and the quality of the strip can be improved.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of the present invention, and FIG. 2 is a bottom view showing the main parts thereof. In the figure, 1 is a fixed roll, 2a, 2b are moving rolls, 3 is a looping pit, 4 is a loop car, 5 is a metal strip (band-shaped body), 6 is a rope (linear body), 7 is a winding drum, lla, llb is a tension detection means, 12a to 12d are vibrating press rollers, 13a to 13b are position regulating rollers, 15
a, 15b. Load cell, 16 is adder, 17 is tension control circuit, 18
19 is a reference tension setting circuit, 19 is a current control circuit, 20 is a reference current value setting circuit, 21 is a motor drive circuit, and 23 is a drive motor.

Claims (1)

[Claims] The belt-shaped body is wound alternately between a required number of fixed rolls and a required number of moving rolls, and a moving body that moves the moving roll is pulled by a winding drum via a linear body. In the looper, the tension of the linear body is controlled by a linear body tension detection means disposed near the winding drum of the linear body, and a tension detection signal of the tension detection means and a predetermined reference signal. It is characterized by comprising a tension control means for comparing and outputting a tension control signal, and a drive current control means for controlling the drive current of the motor for driving the winding drum based on the tension control signal from the tension control means. A belt tension control device for a looper.