JPH079610B2 - Tension control device for long materials - Google Patents

Description

Description: TECHNICAL FIELD [0001] The present invention relates to a tension control device for a long material, which controls the tension of a long material running between two sets of conveying devices to a predetermined value. .

[Prior art and its problems]

When a long material such as a strip of metal or paper that is in the form of a strip or a wire is transferred by a conveying means such as a bridle roll, it is necessary to control the tension of this long material in the middle of the bridle rolls to an appropriate value. is there.

FIG. 3 is a view showing a conventional example in which the tension of a long material running in the middle of two sets of conveying means is detected. The long material 2 has a velocity of V _C from the left side of FIG. Run in,
It runs rightward at a speed of V _D via a first bridle 3 as a first conveying means and a second bridle 4 as a second conveying means. First bridle 3 and second bridle 4
A looper 5 serving as a tension generating means is provided between the looper 5 and the looper 5 so that the looper 5 can move left and right in response to the speed difference between the running speed V _C and the running speed V _D of the long material 2. Thus, the required tension is applied to the long material 2 while absorbing the above-mentioned speed difference.

In order to keep the tension of the long material 2 in the middle between the first bridle 3 and the second bridle 4 constant, for example, there has conventionally been a method of controlling the armature current of the electric motor driving the looper 5 to a constant value. However, this method requires a compensating circuit in order to provide a precise control method that also considers the acceleration / deceleration torque when the motor is accelerated / decelerated, and the circuit configuration is complicated and expensive. Moreover, it has a drawback that it is impossible to effectively suppress the tension vibration generated when the traveling speed of the long material 2 changes, although the circuit is complicated and expensive.

Therefore, as shown in the conventional example of FIG. 3, a tension sensor such as a load cell designated by reference numeral 6 is provided in order to directly detect the tension of the long material 2 which is running between the bridles 3 and 4. A method is widely used in which the actual tension value signal obtained from the tension sensor 6 through the tension detection circuit 7 is applied to the armature current control system of the electric motor that drives the looper 5 to perform feedback control. However, in the case of the conventional example shown in FIG. 3, the tension sensor 6 is generally expensive and, in many cases, the installation location is restricted, making installation impossible or maintenance and inspection extremely difficult. Further, there is still a drawback that it is difficult to suppress the tension vibration generated when the traveling speed of the long material 2 changes.

[Object of the Invention]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a tension control device for a long material that can effectively suppress tension vibration by using an inexpensive tension detecting means that indirectly detects the tension of the long material.

[Main points of the invention]

According to the present invention, the tension applied to the long material is determined from the armature current and the rotation speed of the electric motor that drives the tension generating means that applies tension to the long material running between the two sets of conveying means. A tension estimated value calculating means for calculating an estimated value is provided, and an estimated tension value output from this is fed back to the tension adjusting means, and a speed difference signal between the speed at which the long material comes in and the speed at which it runs out. By inputting the output signal of the tension adjusting means and the speed control system as a minor loop of the tension control system, effective tension control is performed.

Example of Invention

FIG. 1 is a control block diagram showing an embodiment of the present invention.
The details of the present invention will be described below with reference to FIG.

In FIG. 1, the long material 2 is conveyed from the left side to the right side by the first bridle 3 as the first conveying means and the second bridle 4 as the second conveying means. Entry speed of V _C , second bridle 4
Is the traveling speed V _D , the speed difference between the traveling speed V _C and the traveling speed V _D is absorbed, and the length of the long material 2 intermediate between the first bridle 3 and the second bridle 4 is determined. The looper 5 as the tension generating means is provided to apply the above tension, as in the case of the conventional example described in FIG.

The first bridle motor 31 that uses a DC motor drives the first bridle 3, and the speed of the first bridle motor 31 is controlled by a speed setter 37, a speed controller 36, a current controller 35, and a current controller 35. Detector 34 and speed generator 32
This can be achieved by controlling the power converter 33 that converts the alternating current into the direct current by the speed control system configured by. Similarly, the speed control of the second bridle motor 41 for driving the second bridle 4 is also performed by the speed setter 47, the speed adjuster 46, the current adjuster 45,
This can be achieved by controlling the power converter 43 by a speed control system composed of the current detector 44 and the speed generator 42.

The looper 5 as a tension generating means installed to give a tension T to the long material 2 running between the first bridle 3 and the second bridle 4 is a looper electric motor 51.
The actual value I of the armature current, which is converted into direct current by the power converter 53 and flows through the looper electric motor 51, is detected by the current detector 54, and the speed generator connected to the looper electric motor 51 is driven. The actual rotational speed value N is detected by 52.

The estimated tension value calculation circuit 57 receives the estimated current value signal I and the actual velocity value signal N described above to calculate the estimated tension value signal T.
^* Is calculated and given to the tension adjuster 58. The estimated tension value signal T ^* and the desired tension value signal output from the tension setter 59 are input to the tension adjuster 58, and the tension adjuster 58 outputs a speed signal that makes the deviation between the two input signals zero. Is output.

V from the speed generator 32 corresponds to the running speed of the long material 2.
_A velocity signal _C is output, and similarly, a velocity signal V _D corresponding to the running velocity of the long material 2 is obtained from the velocity generator 42. Therefore, the velocity deviation V _C between these bridles 3 and 4 is V _C.
-V _D and the speed signal output from the tension adjuster 58 are input to the speed adjuster 56 to output a current target value signal that makes the deviation between both input signals zero. Further, the deviation between the current target value signal and the actual current value signal I detected by the current detector 54 is input to the current controller 55, and a control signal for making this input deviation zero is given to the power converter 53, and Power converter 53
The looper electric motor 51 is operated at a desired speed by controlling the output DC voltage of. Therefore, the tension of the long material 2 located between the bridles 3 and 4 can be controlled to a predetermined value T.

FIG. 2 is a block diagram showing a configuration of a tension estimated value calculation circuit in the embodiment circuit shown in FIG. This second
In the figure, the looper motor 51, the speed generator 52, the power converter 53, the current detector 54, the current controller 55, the speed controller 56, the tension controller 58 and the tension setter 59 have already been described in FIG. Therefore, these explanations are omitted. The code
51F is the field of the looper electric motor 51.

The estimated tension value calculation circuit 57 includes a magnetic flux calculator 61, a multiplier 62, a function generator 63, a divider 64, integration circuits 65 and 67, and a proportional circuit 66.
And 68, and the long material 2 as shown below.
The estimated tension value T ^* is calculated (a value with a symbol * indicates the estimated value).

By giving the actual speed value signal N from the speed generator 52 to the magnetic flux calculator 61, the field magnetic flux Φ of the looper motor 51 is calculated, and the actual magnetic flux value Φ and the actual current value signal I obtained from the current detector 54 are calculated. The electric motor torque actual value T _M is calculated by multiplying and by a multiplier 62, and the electric motor load torque estimated value T _L ^* is simulated by the electric motor torque actual value T _M and the electric motor speed actual value signal N. To That is, the difference between the actual motor torque value T _M and the simulated estimated motor load torque value T _L ^* is calculated by the integration circuit 65.
The simulated motor speed estimated value N ^* is output by inputting the value to J. The value J, which is included in the integration circuit 65, represents the integration time corresponding to the change in the actual motor speed from the change in the motor torque. By inputting the difference between the simulated motor speed estimated value N ^* and the simulated motor speed actual value signal N into the integration circuit 67, the simulated motor load torque estimated value T _L ^*
This estimated load torque value T _L ^* detects only the torque component with respect to the electric motor load, and does not include the electric motor acceleration / deceleration torque included in the actual electric motor load torque value. Since this motor acceleration / deceleration torque cannot be easily detected, it is possible to easily estimate the torque amount applied to the load by obtaining the load torque estimated value T _L ^* . The integrating circuit 67 is the velocity difference that is input is zero, i.e. N = N ^* and the motor load torque estimated value is output until T _L ^* continues to change, N = N ^* and the electric motor load torque estimated when it The value T _L ^* is the same value as the motor load torque actual value T _L.

In the simulation operation by the circuit described above, it is necessary to consider that the estimated motor speed value N ^* can always stably follow the actual motor speed value N. Therefore, input value N-
A proportional circuit 66 having a gain of G _{1 with} respect to N ^* is installed on the input side of the integrating circuit 65, and a proportional circuit 68 having a gain of G ₂ is also installed on the input side of the integrating circuit 67 for feedback. . By properly selecting these feedback gains G ₁ and G ₂ , the estimated motor load torque value _TL
The response when getting ^* can be adjusted optimally.

When the estimated motor load torque value _TL ^* simulated as described above is input to the divider 64 and _TL ^* is divided by the roll diameter of the looper 5, the estimated tension value of the long material 2 is obtained. T ^* is obtained. Thus, by inputting the estimated tension value T ^* output from the estimated tension value calculation circuit 57 into the tension adjuster 58 together with the tension set value, the tension of the long material 2 running between the bridles 3 and 4 is tensioned. Can always be controlled to a desired tension set value.

〔The invention's effect〕

According to the present invention, the armature current and the rotation speed of the electric motor for driving the tension generating means for applying tension to the running long material in the middle of the two sets of carrying means for carrying the long material are detected. Provided with an estimated tension value calculation means for calculating an estimated tension value of the long material from the current and speed, and controlling the tension generation means so that the estimated tension value obtained from the estimated tension value matches the desired tension set value. I am trying. This circuit configuration eliminates the need for expensive mechanical tension detecting means such as a load cell that has been conventionally used and that has many restrictions on the mounting location. Therefore, the tension control device can be inexpensively constructed. Have. Furthermore, since the gain adjustment of the feedback circuit in the process of calculating the estimated tension value in the estimated tension value calculation means can be optimally set,
Since a quick and stable response can be obtained, it is possible to suppress the occurrence of tension vibration even when the traveling speed of the long material changes, and it is possible to exert an effect that there is no possibility of degrading the quality of the long material.

[Brief description of drawings]

FIG. 1 is a control block diagram showing an embodiment of the present invention.
FIG. 2 is a block diagram showing a configuration of a tension estimated value calculation circuit in the embodiment circuit shown in FIG. FIG. 3 is a diagram showing a conventional example in which the tension of a long material running in the middle of two sets of conveying means is detected. 2 ... Long material, 3 ... First bridle as first conveying means, 4 ... Second bridle as second conveying means,
5 ... Looper as tension generating means, 6 ... Tension sensor, 7 ... Tension detection circuit, 31 ... First bridle motor, 41 ... Second bridle motor, 51 ... Looper motor, 32, 42, 52 ...... Speed generator, 33,43,53 …… Power converter, 34,44,54 …… Current detector, 35,45,55 …… Current regulator, 36,46,56 …… Speed regulator, 37,47 ...... Speed setting device, 5
7 …… Tension estimated value calculation circuit, 58 …… Tension adjuster, 59 ……
Tension setting device, 61 ... Magnetic flux calculator, 62 ... Multiplier, 63 ... Function generator, 64 ... Divider, 65,67 ... Integrating circuit, 66, 68 ...
… Proportional circuit.

Claims (2)

[Claims] 1. A long strip provided with a first transporting means and a second transporting means for transporting a long strip of material, and a tension generating means for applying a predetermined tension to the long strip of material in between these two transporting means. In the material conveying device, the actual torque value of the electric motor is calculated from the actual electric current value and the actual speed value of the electric motor that drives the tension generating means, and the electric motor load torque is estimated from the actual electric motor torque value and the actual electric motor speed value. And a tension estimated value calculation means for simulating the value and calculating the tension estimated value applied to the long material from the motor load torque estimated value, and feeding back the tension estimated value to eliminate the deviation from the tension set value. And a tension adjusting means output signal, and a minor loop for inputting a speed deviation between the speed of the first conveying means driving motor and the speed of the second conveying means driving motor. Tension controller of the elongated material, characterized in that the degree control system provided in the tension generating unit drive motor. 2. The tension control device for a long material according to claim 1, wherein the estimated motor load torque value in the estimated tension value calculation means is simulated by an actual motor speed value and an estimated motor load torque value. And an integrator that outputs a simulated motor speed estimated value by inputting the difference between the motor speed actual value and the simulated motor speed estimated value by inputting the difference between the actual motor speed actual value and the simulated motor speed estimated value. A tension control device for a long material, which is performed by another integrating means that outputs a value.