JP2906838B2 - Tension control device for winding / unwinding machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tension control device for conveying a material by a constant tension control in a winding / unwinding machine.

[0002]

2. Description of the Related Art In a winding / unwinding machine, when winding and unwinding a material under constant tension control, a torque (motor torque) to be output by a motor as a driving source is a tension torque and a mechanical loss compensation torque. In order to calculate the torque corresponding to the tension, the winding diameter of the material on the winding / unwinding roll or the like is required. This winding diameter is usually calculated by the line speed, which is the material conveying speed, and the rotation speed of the winding / unwinding roll drive motor. Here, the line speed is detected by operating a speed detector such as a speed generator using a line speed detection roll that rotates in contact with the conveyed material.

However, if a slip occurs between the material and the roll for detecting the speed, the detected value of the line speed becomes inaccurate, and the winding diameter becomes inaccurate, resulting in an error in the calculation of the torque corresponding to the motor tension. Will happen. In such a case,
Conventionally, without correcting the winding diameter in which an error has occurred due to the slip, only the tension deviation of the material (the deviation between the set tension value and the detected tension value) is adjusted by a PI (proportional integral) controller. Constant control was performed.

[0004]

However, since the conventional method is not a method of correcting the winding diameter itself, the calculated torque of the motor tension still includes an error, and as a result, an accurate tension is obtained. There was a problem that constant control could not be performed. The present invention has been made to solve the above problems, and an object of the present invention is to correct an accurate tension by correcting a winding diameter itself in which an error has occurred due to a slip between a material and a speed detecting roll. An object of the present invention is to provide a tension control device for a winding / unwinding machine capable of performing constant control.

[0005]

In order to achieve the above-mentioned object, the present invention provides a method for driving the winding / unwinding roll so as to keep the tension of the material conveyed by the winding / unwinding roll constant. While controlling the motor torque, the motor torque is calculated by the sum of the tension component torque and the mechanical loss compensation torque, and the tension component torque is calculated based on the winding diameter and the tension set value of the winding / unwinding roll. Means for detecting a tension deviation caused by a slip generated between a roll for detecting the winding diameter and a line speed detecting material, and a tension deviation exceeding a set value. Means for correcting the winding diameter by adding a correction amount to the detected value of the winding diameter at the time of occurrence.

[0006]

According to the present invention, when a slip occurs between the line speed detecting roll and the material, the detected line speed decreases, and the detected value of the winding diameter of the winding / unwinding roll also decreases. At the same time, the tension detection value also decreases, so when the tension deviation exceeds a certain value, a preset winding diameter correction amount is added to the winding diameter detection value to correct the winding diameter. As a result, a decrease in the winding diameter detection value due to the slip is compensated, and an accurate winding diameter detection value is obtained. Performs constant tension control.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of the tension control device according to this embodiment. Although this embodiment relates to the operation at the time of unwinding the material, the present invention can be similarly applied to the winding of the material. In the figure, 1
Reference numeral 2 denotes an unwinding roll, and a roll 1 for line speed detection and a roll 4 for tension detection are in contact with the material 1. A speed generator 5 is connected to the speed detection roll 3, and a tension detector 6 is connected to the tension detection roll 4. Reference numeral 7 denotes an unwinding motor for driving the unwinding roll 2, and a speed generator 8 for detecting the number of revolutions is attached to the motor 7.

The rotation speed N of the motor 7, which is the output of the speed generator 8, is input to a divider 9, and by dividing the line speed V input from the speed generator 5, The winding diameter D is detected. This winding diameter D is input to one input terminal of the adder 10.

On the other hand, reference numeral 11 denotes a tension setter, and a tension set value T ^* by the setter 11 is applied to one input terminal of each of adders 12 and 13. The tension T of the material 1 detected by the tension detector 6 is input to the other input terminal of the adder 12. The tension deviation ΔT (= T ^* −T) output from the adder 12 is determined by the PI controller 1
4, the output of the PI adjuster 14 is applied to the other input terminal of the adder 13, and the output of the adder 13 is applied as tension T to one input terminal of a multiplier 18 described later. I have.

[0010] The tension deviation ΔT is also input to a comparator 15 where the tension deviation ΔT is set to a set value K.
In this case, the comparison detection signal is sent to the subsequent comparison relay 16. 17 is comparison relay 1
6 when the comparison relay 16 is not operating, there is no input amount to the other input terminal of the adder 10 (input “zero”), and when the comparison relay 16 is operating, the winding diameter correction amount ΔD
Is controlled to be input to the adder 10.

With such a configuration, the output of the adder 10 is the detected value of the winding diameter D itself or a correction value (D + ΔD) obtained by adding the winding diameter correction amount ΔD.
Is multiplied by the tension T, and is output as a tension torque τ _T. The tension component torque τ _T is added to the mechanical loss compensation component torque τ _L by the adder 19 and is input to the unwinding motor 7 as a motor torque τ _M.

When the motor 7 is accelerated or decelerated immediately after the unwinding of the material 1 or immediately before the unwinding, the motor torque τ _M is added to the tension torque τ _T in order to keep the tension constant. It is the sum of the deceleration torque τ _A and the mechanical loss compensation torque τ _L.
That is, τ _M = τ _T + τ _A + τ _L. Then, when acceleration and deceleration are completed and the speed becomes constant, τ _A = 0, so that τ _M = τ _T + τ _L.

The configuration shown in FIG. 1 is for realizing the state of τ _M = τ _T + τ _L , and its operation will be described below. If there is no slip between the line speed detection roll 3 and the material 1, the multiplier 18 turns the winding diameter value D and the tension T
Is multiplied to calculate the tension torque τ _T. Here, if the detected tension value T is equal to the set tension value T ^* , the tension deviation ΔT = 0, and the multiplier 18 calculates the tension torque τ _T by the product of the winding diameter value D and the set tension value T ^*. . This tension component torque τ _T is added to the mechanical loss compensation torque τ _L in the adder 19 and is input to the unwinding motor 7 as a motor torque τ _M. Thereby, the unwinding motor 7 is unrolled so that the material 1 is unwound with a constant tension equal to the tension set value T ^*.
Can be driven.

Next, when a slip occurs between the speed detection roll 3 and the material 1, the line speed detection value V becomes smaller than the original value, and accordingly, the winding diameter D, which is the output of the divider 9, is obtained. The detection value also becomes smaller. Tension min torque tau _T obtained by the multiplier 18, since the tension deviation ΔT is in the state of zero is the product of the tension setting value T ^* and the winding diameter D, even tension corresponding torque tau _T by reducing the winding diameter D decreases I do. As a result, the motor torque τ _M decreases, and the tension T detected by the tension detector 6 also decreases.

At this time, when the tension deviation ΔT (= T ^* −T) calculated by the adder 12 becomes equal to or more than the set value K of the comparator 15, the comparison relay 16 operates according to the comparison detection signal to switch the contact point 17. In operation, the winding diameter correction amount ΔD is applied to one input terminal of the adder 10. Accordingly, the detected value of the winding diameter D reduced by the slip is corrected by the winding diameter correction amount ΔD, and the correction value (D + Δ
D) is output. Therefore, the multiplier 18 multiplies the winding diameter correction value (D + ΔD) by the tension T to obtain a tension torque τ.
Calculate _T.

As described above, in the present embodiment, the winding diameter D reduced due to the slip generated between the speed detecting roll 3 and the material 1 is determined by the deviation between the tension set value T ^* and the detected tension value T. The correction is performed when ΔT becomes equal to or greater than the set value K to correct the tension torque τ _{T and,} consequently, the motor torque τ _M.
Therefore, even when a slip occurs, the motor torque τ _M can be maintained constant, and stable tension constant control can be performed.

According to this embodiment, the unwinding roll 2
Can be measured in a non-contact state, so that there is no inconvenience such as scratching the material 1 or changing the tension due to the contact with the unwinding roll 2. Further, in a system such as an unwinder that stops the line when the remaining amount of the winding diameter D of the unwinding roll 2 (the remaining length of the material 1) reaches a certain value, the winding diameter D and the known material thickness are used. Since the remaining length of the material 1 can be calculated accurately from the above, it is extremely useful in operation.

[0018]

As described above, according to the present invention, when a slip occurs between the line speed detecting roll and the material, when the tension deviation exceeds the set value, the winding diameter detection value is corrected and the tension component is corrected. This is to correct the torque. Therefore, in comparison with the conventional method in which the change in the detected winding diameter due to slip is ignored and the tension deviation is simply adjusted by PI, the accurate corrected detected winding diameter is used in calculating the torque corresponding to the tension. The required torque for the tension and the motor torque can be accurately calculated, and stable constant tension control can be performed.

Further, in the present invention, since the winding diameter can be accurately calculated in the control process, the present invention can be applied to, for example, remaining length stop control of a material.

[Brief description of the drawings]

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

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Material 2 Unwinding roll 3 Line speed detecting roll 4 Tension detecting roll 5,8 Speed generator 6 Tension detector 7 Unwinding motor 9 Divider 10,12,13,19 Adder 11 Tension setter 14 PI adjustment Unit 15 Comparator 16 Comparison relay 17 Contact 18 Multiplier

Claims (2)

(57) [Claims] The torque of a motor for driving the winding / unwinding roll is controlled so that the tension of the material conveyed by the winding / unwinding roll is kept constant, and the motor torque is reduced by a torque corresponding to the tension. And a tension control device that calculates the tension component torque based on a winding diameter and a tension set value of the winding / unwinding roll, and detects the winding diameter. Means for detecting a tension deviation caused by slip generated between the line speed detection roll and the material, and adding a correction amount to the winding diameter detection value when the tension deviation becomes equal to or greater than a set value. A tension control device for a winding / unwinding machine, comprising: 2. The winding and unwinding machine according to claim 1, wherein a winding diameter of the winding and unwinding roll is detected based on a rotation speed and a line speed of a motor for driving the winding and unwinding roll. Tension control device.