JPH058916A - Rewinder control device - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a rewinder control device capable of suppressing tension fluctuation due to the influence of an intermediate roll, without depending on process conditions. [Structure] Torque calculation means 33 and 34 for calculating acceleration / deceleration torque and mechanical loss torque of the intermediate roll 6 by using a speed reference or an actual speed signal, and both torques calculated by the torque calculation means and the intermediate roll are driven. A rewinder control device comprising: drooping amount adjusting means 37 for adjusting the drooping characteristic amount of the electric motor so that the generated torque of the electric motor 9 becomes equal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an unwinder on which a sheet material is wound and a rotation speed of an intermediate roll provided between a winder for winding the sheet material wound on the unwinder and a winding speed of the winder. The present invention relates to a rewinder control device that controls speed according to a speed standard corresponding to.

[0002]

2. Description of the Related Art As shown in FIG. 2, a rewinder device is a device for winding a sheet material 1 rewound from an unwinder 2 on a winding roll 3. The winding roll 3 is surface-driven by the rear drum 4 and the front drum 5. An intermediate roll 6 and a tension detecting roll 7 are provided between the unwinder 2 and the winding roll 3. The unwinder 2 is driven by the electric motor 8, and the intermediate roll 6
Is driven by the electric motor 9, and the rear drum 4 is driven by the electric motor 1.
0, and the front drum 5 is driven by the electric motor 11. The winding tension of the sheet material 1 is detected by the tension detector 12 in cooperation with the tension detection roll 7,
The tension detection signal T is output. The electric motor 8 has a control circuit 13
The electric motor 9 is controlled by the control circuit 14, and the electric motors 10 and 11 are controlled by the control circuit 15.

The control circuit 13 includes a tension setting device 16 for setting a tension reference, an inertia compensation circuit 17 for compensating for a tension error due to the inertia of the unwinder 2 itself, a set tension signal from the tension setting device 16, and a tension detector 12. A tension control circuit (TC) 18 that forms a tension control signal based on the tension feedback signal T obtained by the above and the output signal of the inertia compensation circuit 17, and based on the tension control signal output from the tension control circuit 18. It is composed of a current control circuit (CC) 19 that forms a current control signal, and a power converter 20 that supplies a predetermined current to the electric motor 8 according to the current control signal output from the current control circuit 19.

The control circuit 15 determines the deviation between the speed reference circuit 21 for instructing the winding speed reference and the speed reference from the speed reference circuit 21 and the actual speed detected by the speed detector 22 attached to the electric motor 10. A speed control circuit (SC) 23 that forms a speed control signal based on the current control circuit 24, a current control circuit (CC) 24 that forms a current control signal on the rear drum 4 side based on the speed control signal from the speed control circuit 23, and a current control circuit 24. Motor 1 according to the current control signal formed by
0, a power converter 25 for supplying a current, and a speed control circuit 2
A current control circuit (CC) 26 that forms a current control signal on the front drum 5 side based on the speed control signal from No. 3, and a power converter that supplies a current to the electric motor 11 according to the current control signal formed by the current control circuit 26. And 27.

The control circuit 14 uses the speed reference from the speed reference circuit 21 minus the amount corresponding to the amount of droop set by the droop amount setting device 28 as the speed reference of the intermediate roll 6, and detects the speed attached to the electric motor 9. Speed control circuit (SC) 30 that forms a speed control signal based on the deviation from the actual speed detected by the device 29, and a current control circuit (CC) that forms a current control signal based on the speed control signal from the speed control circuit 30. ) 31 and a power converter 32 that supplies current to the electric motor 9 according to the current control signal generated by the current control circuit 31.

In the rewinder controller constructed as described above, the control circuit 14 calculates the deviation between the speed reference set by the speed reference circuit 21 and the actual speed signal detected by the speed detector 22 to control the speed. The circuit 23 forms a speed control signal for making the actual speed equal to the speed reference, and the currents of the electric motors 10 and 11 are controlled via the current control circuits 24 and 26 and the power converters 25 and 27. As a result, the winding of the sheet material 1 at a constant speed is achieved.

The speed reference of the intermediate roll 6 is obtained by subtracting the output signal of the droop amount setting unit 28, that is, the speed corresponding to the droop amount from the speed reference set by the speed reference circuit 21. The droop amount setter 28 is configured to divide the output signal of the speed control circuit 30 and perform an appropriate level conversion. When the speed control signal output from the speed control circuit 30, that is, the load on the intermediate roll 6 increases, the droop amount setter 28 droops. The output of the quantity setter 28 also increases and decreases the speed reference of the intermediate roll 6. That is, the so-called drooping characteristic is realized in which the speed of the electric motor 9 is reduced in accordance with an increase in the load of the electric motor 9. The reason for providing such characteristics is to try to adjust the speed of the intermediate roll 6 appropriately when there is a difference in speed between the intermediate roll 6 and the sheet material 1. For example, when the speed of the intermediate roll 6 is faster than the speed of the sheet material 1, the load of the electric motor increases, so that the speed of the intermediate roll 6 is reduced and balanced with the speed of the sheet material 1.

The sheet material tension detected by the tension detecting circuit 12 is matched with the tension set by the tension setting circuit 16 so that the deviation between them is made zero, that is, the actual tension becomes equal to the set tension. The electric current of the electric motor 8 is controlled.

[0009]

The conventional rewinder control device described above has a problem that the tension fluctuation is large when the winding roll 3 is accelerated or decelerated. This will be described below.

Assuming that the speed difference between the intermediate roll 6 and the take-up roll 3 is Δv and the Young's modulus of the sheet material 1 is Y, the tension error ΔT caused by the speed difference Δv is

[Equation 1] Therefore, a tension error ΔT occurs between the unwinder tension T _u and the winder tension T _w . While the tension error ΔT is small, the equation (1) is followed, but when the tension error ΔT becomes larger than the frictional force between the intermediate roll 6 and the sheet material 1, the sheet material 1 starts to slide on the intermediate roll 6. The tension error at this time is ΔT ′, the speed difference between the intermediate roll 6 and the sheet material 1 is Δv ′, the dynamic friction coefficient is μ, and the sheet material 1 is the intermediate roll 6
If the area in contact with is A, then ΔT ′ = Δv ′ · μ · A (2)

On the other hand, the intermediate roll 6 and the take-up roll 3
An error occurs in the speed of 1 due to a control error and a difference in speed response. Especially during acceleration / deceleration, the speed difference becomes large due to the difference in speed response between the two. The open loop open loop transfer function G of the speed control system of the winding roll 3 has a Laplace operator S, a gain constant K, a speed control circuit time constant T ₁ , a current control system time constant T ₂ , and a winding G = (K (1+ (1 / T ₁ ) S)) / (JS ² (1+ (1 / T ₂ ) S)) (3) where J is the total moment of inertia of the roll 3 and its drive motor. expressed. The moment of inertia of the take-up roll 3 increases as the roll diameter increases. For this reason, the gain of the open loop transfer function G of the equation (3) decreases as the roll diameter increases, and the velocity response becomes slow. Further, the moment of inertia of the take-up roll 3 also changes depending on the density and width dimension of the sheet material 1, so the speed response also changes depending on the product type. On the other hand, since the moment of inertia of the intermediate roll 6 is always constant, the speed response does not change. Therefore, the speed response of the intermediate roll 6 and the take-up roll 3 is different due to the difference in coil diameter or the kind of the take-up roll 3. Therefore, when the speed reference is changed, the intermediate roll 6
There is a difference in the time required for the take-up roll 3 and each of the take-up rolls 3 to reach the target speed, resulting in a speed difference between the two. When this speed difference occurs, the tension error first increases according to the equation (1), and when it reaches the maximum point and exceeds the frictional force, slippage begins to occur between the sheet material 1 and the winding roll 3, The tension error decreases to a value according to the equation (2). Therefore, it is an important problem to reduce the tension error in the region of the equation (1).

In the conventional rewinder control device, if a speed difference occurs between the intermediate roll 6 and the winding roll 3, (1)
A tension error occurs according to the formula, and the load on the intermediate roll 6 increases or decreases by this amount. However, since the intermediate roll 6 is speed-controlled, the load increase / decrease depends on the increase / decrease of the speed control signal output from the speed control circuit 30, that is, the increase / decrease of the current control signal output from the current control circuit 31. By adjusting the amount, the speed of the intermediate roll 6 is compensated so as to match the speed of the take-up roll 3.

However, as can be seen from the equation (1), since the tension error ΔT is proportional to the integral value of the speed difference Δv, the level of the speed difference differs depending on the process situation even under the same tension error. Moreover, since the Young's modulus Y differs depending on the type of sheet material, the relationship between the tension error ΔT and the speed difference Δv is not constant. In other words, since the optimum value of the drooping amount depends on the process conditions, conventionally, even if the optimum drooping amount is adjusted under certain conditions, if the conditions change, it will deviate from the optimum value and a large tension fluctuation will occur. There was an inconvenience that it would end up.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a rewinder control device capable of suppressing the tension fluctuation due to the influence of the intermediate roll without being affected by the process conditions.

[0015]

In order to achieve the above object, the rewinder control device of the present invention calculates the acceleration / deceleration torque and the mechanical loss torque of the intermediate roll by using the speed reference or the actual speed of the intermediate roll. Means, and drooping amount adjusting means for adjusting the drooping characteristic amount of the electric motor so that the both torques calculated by the torque calculating means and the generated torque of the electric motor driving the intermediate roll become equal. ..

[0016]

[Function] Ideally, the intermediate roll should ideally be driven so as not to affect the running of the sheet material. For that purpose, the intermediate roll has a total value of its own mechanical loss torque and acceleration / deceleration torque. It is sufficient to control the output torque of the drive motor as described above. The present invention is made in view of this point, and calculates the acceleration / deceleration torque and the mechanical loss torque of the intermediate roll by using the speed signal of the winding roll, and adds the two signals to obtain the intermediate value. The torque of the roll drive motor is used as a reference, and the actual torque of the intermediate roll drive motor is controlled by adjusting the amount of sag of the intermediate roll according to the deviation between the torque reference and the actual torque. By doing so, the intermediate roll does not affect the traveling of the sheet material, and it is possible to eliminate the tension fluctuation that has been conventionally caused due to the speed difference between the intermediate roll and the winding roll.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in more detail below with reference to the drawings.

FIG. 1 shows an embodiment of the present invention. 1, the same parts as those in FIG. 2 are designated by the same reference numerals, and the description of those parts will be omitted.

The rewinder control device shown in FIG. 1 is based on the control device shown in FIG. 2 and further includes an inertia compensation circuit 33 for calculating the acceleration / deceleration torque of the intermediate roll and a mechanical loss compensation circuit for calculating the mechanical loss torque of the intermediate roll. 34, an inertia compensating circuit 33, and a mechanical loss torque calculating circuit 34, output signals of the adder 35, which calculates the torque reference of the intermediate roll, and a current detector 3 which detects the actual current of the intermediate roll drive motor 9.
6, and a drooping amount control circuit 37 that outputs a drooping amount correction signal from the deviation between the intermediate roll torque reference output from the adder 35 and the actual torque obtained based on the actual current detected by the current detector 36 is added. Has been done. In addition, in order to calculate the acceleration / deceleration torque and the mechanical loss torque of the intermediate roll by the inertia compensation circuit 33 and the mechanical loss compensation circuit 34,
In the above embodiment, the one using the speed reference given from the speed reference circuit 21 is shown, but this is characterized in that a stable torque value in a feedforward manner can be obtained. Depending on the case, the actual speed obtained via the speed detector 29 attached to the electric motor 9 may be used. However, in this case, it is necessary to consider that the fluctuation amount of the actual speed may act in a disturbance manner.

The torque of the intermediate roll 6 is controlled by adjusting the amount of droop of the intermediate roll drive motor 9 by the rewinder control device constructed as described above.

In the inertia compensation circuit 33, the speed reference signal of the winding roll is differentiated, and the acceleration / deceleration torque is calculated by multiplying the value by the inertia moment of the intermediate roll 6.
Since the mechanical loss of the intermediate roll is generally a function of the roll rotation speed, the mechanical loss compensation circuit 34 includes a function generator,
The mechanical loss torque is calculated based on the take-up roll speed reference signal, and a signal representing it is output. The output signals of the inertia compensation circuit 33 and the mechanical loss compensation circuit 34 are added together to calculate the torque reference signal of the intermediate roll 6. On the other hand, when the intermediate roll drive motor 9 is a DC machine, its output torque is proportional to the armature current, so the current detector 36 detects the armature current of the motor and calculates the actual torque based on the detected current. To do. A deviation between the signal representing the actual torque and the torque reference signal output from the adder 35 is arithmetically amplified by the drooping amount control circuit 37 to generate a drooping amount correction signal. By correcting the output signal of the drooping amount setting device 28 with this drooping amount correction signal, the torque generated by the drive motor 9 for the intermediate roll 6 is controlled via the speed control circuit 30, the current control circuit 31, and the power converter 32. To do.

In this way, the inertia compensation torque and the mechanical loss torque reference of the intermediate roll 6 are calculated, and by comparing them with the actual torque to adjust the drooping amount characteristic, the torque of the intermediate roll 6 is always driven by its own roll. Since it is possible to control the torque value required for the above, the tension fluctuation can be suppressed without affecting the traveling of the sheet material 1.

[0023]

According to the present invention, since the driving torque of the intermediate roll can be controlled to the torque value required for driving the own roll, it does not affect the running of the sheet material, and the conventional intermediate roll is used. It is possible to realize a rewinder control device capable of removing the tension fluctuation that has occurred due to the speed difference between the winding roll and the winding roll.

[Brief description of drawings]

FIG. 1 is a block diagram of a rewinder control device according to an embodiment of the present invention.

FIG. 2 is a block diagram of a conventional rewinder control device.

[Explanation of symbols]

 2 Unwinder 3 Winding roll 6 Intermediate roll 9 Motor 14 Control circuit 21 Speed reference circuit 28 Droop amount setting device 29 Speed detector 31 Current control circuit 32 Power converter 33 Inertial compensation circuit 34 Mechanical loss compensation circuit 36 Current detector 37 Drooping Quantity control circuit

Claims (1)

Claim: What is claimed is: 1. An unwinder on which a sheet material is wound, and a winder for winding the sheet material wound on the unwinder. In a rewinder control device that controls a speed according to a speed reference corresponding to a speed, a torque calculation unit that calculates the acceleration / deceleration torque and the mechanical loss torque of the intermediate roll by using the speed reference or the actual speed of the intermediate roll, and the torque calculation. A rewinder control device comprising: drooping amount adjusting means for adjusting the drooping characteristic amount of the electric motor so that both torques calculated by the means and the torque generated by the electric motor for driving the intermediate roll become equal.