KR101470906B1 - Metal strip stabilizer and method for manufacturing hot-dip coated metal strip - Google Patents

Abstract

A stabilizer for a metal band capable of avoiding deterioration of a vibration suppressing ability due to an induced current between a vibration suppressing coil and a position correcting coil. A stabilizing device for a metal band according to the present invention comprises a non-contact displacement sensor for measuring a displacement of a metal band (2) during on-line travel, and a control part for inputting a signal from a non-contact displacement sensor and outputting a vibration suppression signal and a position calibration signal A vibration suppressing coil 7a for generating a magnetic force in accordance with the vibration suppression signal outputted from the control unit 5 and a vibration suppressing coil 7b for generating a magnetic force in accordance with the position correcting signal outputted from the control unit 5, A position correcting coil 7b having a number of turns larger than that of the coil 7a is wound in a concentric manner with the vibration suppressing coil 7a and the position correcting coil 7b, A core 6 for guiding the magnetic force generated by the position correcting coil 7b to the metal band 2 and an induction current countermeasure provided in series with the electric circuit for feeding the position correcting coil 7b And a use coil 13a.

Description

TECHNICAL FIELD [0001] The present invention relates to a stabilizing device for a metal band and a manufacturing method of a hot-

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stabilizer for a metal strip, a method for manufacturing a plated metal band using the same, and a metal band manufactured using the metal strip.

Stabilization of the pass line of the metal band by suppressing the vibration or bending of the metal band in the line for manufacturing the metal band not only improves the quality of the metal band but also contributes to improvement of the efficiency of the production line.

For example, in a manufacturing line of a hot-dip metal band, there is a process of attaching a molten metal to a surface of a metal band by dipping a metal band in a hot-dip metal bath while passing through a plate. In this process, excess molten metal adhered to the metal band is shaken off by the wiping gas ejected from the gas wipers installed after the molten metal bath, in order to suppress the occurrence of unevenness in the deposition amount of the molten metal, Is adjusted.

In this adjustment of the molten metal, it is necessary to eject the wiping gas from the gas wipers so that pressure is uniformly applied to the front and back of the metal band in the plate width direction. Therefore, when the distance between the gas wiper and the metal band is not constant, for example, when the metal band is vibrating, when the metal band is warped, or when the pass line of the metal band is shifted somewhere on the front and back sides, And is not uniform in the direction of the passage plate. As a result, there arises a problem that unevenness of molten metal adheres to the surface of the metal band, the width direction of the plate, and the direction of the through plate.

As a method for solving such a problem, there has been known a technique for stabilizing a pass line of a metal band by suppressing bending or vibration of a metal band in a noncontact manner by using an electromagnet. For example, a method in which a pair of electromagnets are arranged so as to oppose each other with respect to a pass line to which a metal band is to be moved, and a method in which the attracting force of each electromagnet is switched to each other while acting on a metal band in accordance with a signal from a separately provided position detector (See Patent Document 1).

In order to suppress the vibration of the metal band using the electromagnet as described above, the responsiveness of the electromagnet is required, and the attracting force of the electromagnet is required for the bending correction and the pass line calibration. Hereinafter, the sum of the bending correction and the pass line correction is referred to as a position correction. In other words, in order to realize vibration suppression and position correction at the same time, it is necessary to have the conflicting properties of response and attraction force. If the number of turns of the coil is increased to increase the attracting force of the electromagnet, the responsiveness of the electromagnet is deteriorated. On the other hand, if the number of turns is decreased in order to improve the responsiveness of the electromagnet, the attractive force of the electromagnet becomes small.

To solve this problem, a metal-to-noncontact control technique using an electromagnet having two independent coils for vibration suppression and position calibration has been proposed (refer to Patent Document 2). According to this technique, it is possible to carry out the vibration control by the vibration suppressing coil having a small number of windings and perform the bending correction and the pass line correction by the position correcting coils having a large number of windings. So that the control can be performed.

Japanese Unexamined Patent Publication No. 2-62355 Japanese Laid-Open Patent Publication No. 2004-124191

However, in the metal-to-contactless control technique using the electromagnet having two independent coils, mutual induction between the vibration suppressing coil and the position correcting coil causes the current change of the vibration suppressing coil to change from position- The current of the position correcting coil affects the current of the coil. Conversely, the current change of the position correcting coil affects the current of the vibration suppressing coil. As a result, there is a problem in that the control technique generates a suction force different from the suction force required by the control signal. In other words, the stabilization device of the metal band using the electromagnets having the two independent coils for vibration suppression and position calibration can control both the vibration suppression capability and the position correction capability at the same time. However, There is a problem that the mutual induction between the coil and the coil lowers the vibration suppressing ability.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a metal band stabilizing device capable of avoiding a decrease in vibration suppressing ability due to an induced current between a vibration suppressing coil and a position correcting coil, And to provide a method for manufacturing a molten plated metal band.

In order to solve the above problems and to achieve the object, a stabilizing device for a metal band according to the present invention includes: a non-contact displacement sensor for measuring a displacement of a metal band during on-line travel; A control unit for outputting a vibration suppression signal for suppressing vibration and a position correction signal for calibrating a position of the metal band; a first coil for generating a magnetic force in accordance with the vibration suppression signal outputted from the control unit; A second coil having a winding number larger than that of the first coil and generating a magnetic force in accordance with a position calibration signal output from the first coil and the second coil, wherein the first coil and the second coil are coaxially wound, A core for guiding the magnetic force generated by the second coil to the metal; a third coil connected in series to the electric circuit for feeding the second coil; It characterized in that it comprises.

According to the stabilizing device of the metal band and the method of manufacturing the molten metal band in accordance with the present invention, it is possible to avoid the deterioration of the vibration suppressing ability due to the induced current between the vibration suppressing coil and the position correcting coil.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view showing a configuration of a stabilizer for a metal band according to an embodiment of the present invention; FIG.
2 is a schematic diagram showing an example of an electromagnet used in a stabilizing device for a metal band according to an embodiment of the present invention.
3 is a block diagram showing the configuration of a control unit in a metal band stabilizing apparatus according to an embodiment of the present invention.
4 is a block diagram for explaining a configuration example of the manipulated variable computing device.
5 is a schematic view showing an electric circuit of an electromagnet in a metal band stabilizer according to an embodiment of the present invention.
6 is a schematic view showing a part of a production line of a general hot-dip coated metal band.
7 is an enlarged view of the vicinity of the gas wiper in the production line of the molten plated metal band.
8 is a graph showing measurement data by a stabilizing device of a metal band of a comparative example.
9 is a graph showing measured data by a stabilizing device for a metal band according to an embodiment of the present invention.
FIG. 10 is a graph for comparing the measured data shown in FIG. 8 with the noise included in the measured data shown in FIG.

(Mode for carrying out the invention)

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a stabilizing device for a metal band according to an embodiment of the present invention will be described with reference to the drawings.

Fig. 1 is a schematic view showing a configuration of a stabilizing device 1 for a metal band according to an embodiment of the present invention. Fig. 1, a metal band stabilizer 1 according to an embodiment of the present invention includes a pair of electromagnets (not shown) provided so as to face each other with a metal band 2 running in the direction of arrow A Contact displacement sensor 4 disposed in the vicinity of the electromagnets 3a and 3b and a control unit 5 for controlling the electromagnets 3a and 3b on the basis of the input from the non- Respectively.

2 is a schematic view showing an example of an electromagnet 3a used in a stabilizing device 1 for a metal band according to an embodiment of the present invention. Although only the electromagnet 3a for the surface of the metal table 2 is described here, the following description is also applicable to the electromagnet 3b for the back surface of the metal table 2. The electromagnet 3a shown in Fig. 2 is constituted by a concentric coil composed of a coil 7a and a coil 7b formed by concentrically winding two coils on one core 6. The two coils 7a and 7b are constituted by changing the number of windings. The coil having the small number of turns of the two coils 7a and 7b is the vibration suppressing coil 7a, For example.

The vibration suppressing coil 7a is required to have such a high responsiveness as to be able to sufficiently follow the vibration frequency of the metal base 2 to be subjected (usually the natural frequency such as bending or twisting of the metal band) In order to suppress the vibration of the natural frequency, a large suction force is not required. Therefore, the number of turns of the vibration suppressing coil 7a is smaller than that of the position correcting coil 7b.

On the other hand, the position correcting coil 7b is not required to have high responsiveness, but is preferably capable of generating a large attractive force with a small current. Therefore, the number of windings of the position correcting coil 7b is preferably as large as the range in which the size of the electromagnet 3a and the value of the electric resistance do not become too large.

The relationship between the number of turns of the coil, the responsiveness of the electromagnet, and the attraction force will be described below.

The operation of the electromagnet is expressed by the equation (1).

e = Ldi / dt + Ri ... (One)

Here, e is the applied voltage, i is the current flowing through the coil, L is the inductance of the coil, and R is the resistance of the coil.

As shown by the equation (1), the current i flowing through the coil is a primary delay system with respect to the applied voltage e, and the time constant T thereof is expressed by equation (2).

T = L / R ... (2)

Here, the inductance L of the coil is proportional to the square of the number of turns N of the coil, and the resistance R of the coil is proportional to the number of turns N of the coil. Therefore, the time constant T is proportional to the number of turns of the coil N by the equation (2). This means that as the number of windings of the coil increases, the time constant increases and the film becomes less responsive.

On the other hand, the attracting force F of the electromagnet is proportional to the square of the number of turns N of the coil and the square of the current i flowing through the coil, as represented by equation (3).

F 留 N ² i ² ... (3)

Therefore, in order to obtain a large attractive force with the same current, it is advantageous to increase the number of turns N of the coil.

In summary, the number of turns (N) of the coil is preferably small in order to increase the responsiveness, but it is good that the attracting force is strong. Therefore, in the electromagnet 3a according to the embodiment of the present invention, the number of revolutions of the vibration suppressing coil 7a requiring no large suction force but requiring high responsiveness is made smaller than the number of turns of the position correcting coil 7b . On the other hand, the number of windings of the position correcting coil 7b requiring a large suction force is set larger than the number of windings of the vibration suppressing coil 7a though high response is unnecessary.

3 is a block diagram showing the configuration of the control section 5 in the stabilizing device 1 for a metal band according to the embodiment of the present invention. 3, the control unit 5 of the metal band stabilizer 1 according to the embodiment of the present invention includes an operation amount computing unit 8, front and back distributing units 9a and 9b, amplifiers 10a and 10b , 10c, and 10d, and inductors 11a and 11b.

The manipulated variable computing device 8 calculates the manipulated variable computing device 8 based on a deviation signal between the measured value of the displacement of the metal band by the non-contact displacement sensor 4 and the target value set by the input means 12, Performs PID control, and outputs a vibration suppression signal and a position correction signal. Fig. 4 is a block diagram for explaining a configuration example of the manipulated variable computing device 8; Fig.

4, the manipulated variable computing device 8 includes a vibration suppression PID control section 8a and a position correction PID control section 8b. The PID control unit 8a for vibration suppression is a calculation means for inputting a deviation signal between the measured value of the displacement of the metal band and the target value and outputting the vibration suppression signal. The PID control unit 8b for position calibration, And outputs a position calibration signal by inputting a deviation signal between the measured value of the displacement of the target and the target value.

Here, the calculation of the vibration suppression PID control section 8a is an operation with an emphasis on responsiveness, and the operation of the position correction PID control section 8b is an operation with an emphasis on a static attraction force. That is, the calculation of the PID controller 8a for vibration suppression is set such that the gain of the high-frequency component included in the input signal is increased, and the calculation of the position calibration PID controller 8b is performed on the basis of the low- Is set to be large. For example, the setting is realized by increasing the setting of the differential gain in the vibration suppression PID control section 8a and increasing the setting of the integral gain in the position correcting PID control section 8b.

Here, the high frequency and the low frequency referred to herein means a high level in comparison between the vibration suppressing PID control unit 8a and the position correcting PID control unit 8b. According to the above arrangement, the vibration suppression signal is a signal containing a large amount of high frequency components, and the position correction signal is a signal including a lot of low frequency components. However, this is because the average value of the frequency components of the vibration suppression signal is Means that there is an overlap between the frequency distribution of the vibration suppression signal and the frequency distribution of the position correction signal.

By constituting the manipulated variable computing device 8 as described above, the manipulated variable computing device 8 obtains, from the measured value of the displacement of the metal band by the non-contact displacement sensor 4, the components used for vibration suppression and the components used for position calibration And transmits the vibration suppression signal and the position correcting signal to the front surface distributor 9a for vibration suppression and the front surface distributor 9b for position correction, respectively.

Referring back to FIG. The front and rear distributor 9a and 9b distribute the vibration suppression signal and the position correcting signal computed by the manipulated variable computing device 8 to the electromagnet 3a for the surface of the metal table 2 and the electromagnet 3b for the back surface, . The amplifier 10a feeds the vibration suppressing coil of the electromagnet 3a in accordance with the vibration suppressing signal for the surface distributed by the front and rear distributor 9a and the amplifier 10b is supplied to the front and rear distributor 9b, To the position correcting coil of the electromagnet 3a in accordance with the position correcting signal for the surface distributed by the electromagnet 3a. On the other hand, the amplifier 10c supplies power to the vibration suppressing coil of the electromagnet 3b in accordance with the back-surface vibration suppression signal distributed by the front-back distributor 9a, and the amplifier 10d supplies the back- 9b in accordance with the position calibration signal for the back surface of the electromagnet 3b.

5 is a schematic diagram showing an electric circuit of the electromagnet 3a in the stabilizing device 1 for a metal band according to the embodiment of the present invention. Here, only the electric circuit for the surface of the electromagnet 3a for the surface of the metal base 2 is shown schematically for the sake of the ground.

As shown in Fig. 5, the vibration suppressing coil 7a and the position correcting coil 7b are connected to the vibration suppressing amplifier 10a and the position correcting amplifier 10b, respectively. The vibration suppressing amplifier 10a feeds the vibration suppressing coil 7a through an electric circuit in accordance with the inputted vibration suppressing signal. The position correcting amplifier 10b feeds the position correcting coil 7b through an electric circuit in accordance with the inputted position correcting signal.

The electric circuit including the position correcting coil 7b and the position correcting amplifier 10b includes a coil 13a as an inductor 11a in series. Hereinafter, this is referred to as an induction current countermeasure coil 13a. The example of the induction current countermeasure coil 13a shown in Fig. 5 shows an example of a coil in which the magnetic circuit 13b is constituted by a closed circuit. The coil in which the magnetic circuit 13b is constituted of a closed circuit is also called a toroidal coil. The magnetic circuit 13b of the inductive current countermeasure coils 13a can also be effected by an open circuit but the inductive current countermeasure coil 13a may be provided so as not to be influenced by environmental changes due to, It is preferable that the magnetic circuit 13b of Fig.

The induction current countermeasure coil 13a configured as described above functions as follows in the metal band stabilizer 1 according to the embodiment of the present invention.

A high frequency current flows in the vibration suppressing coil 7a in accordance with the vibration frequency of the metal band 2. [ Since the vibration suppressing coil 7a and the position correcting coil 7b are formed as concentric coils, a high frequency electromotive force is generated in the position correcting coil 7b by mutual induction.

In the conventional stabilizing device of the metal band, the current of the position correcting coil 7b fluctuates due to the mutual induction electromotive force, and the attracting force of the position correcting coil 7b fluctuates, adversely affecting the vibration control. However, in the metal band stabilizer 1 according to the embodiment of the present invention, since the induction current countermeasure coil 13a is connected to the electric circuit of the position correcting coil 7b, the induction current counter coils 13a The current change of the electric circuit of the position correcting coil 7b can be suppressed by the inductance of the position correcting coil 7b. Hereinafter, a structure for suppressing current fluctuation in the electric circuit of the position correcting coil 7b by the inductive current countermeasure coil 13a will be described.

The current flowing in for the vibration-suppression coils (7a) to i ₁ and, when the current flowing through the coil (7b) for position correction to i _2, the vibration-suppression induced electromotive force (e ₁₎ generated in the coil (7a) and And the induced electromotive force e ₂ generated in the position correcting coil 7b are expressed by the following expressions.

e ₁ = -Mdi ₂ / dt ... (4)

e ₂ = -Mdi ₁ / dt ... (5)

Here, M is a mutual inductance between the vibration suppressing coil 7a and the position correcting coil 7b, and is represented by the following equation.

M = k × (L ₁ × L ₂ ) (6)

Here, k is a coefficient determined by the shape and mutual position of the coil, L ₁ is the inductance of the vibration suppressing coil 7a, and L ₂ is the inductance of the position correcting coil 7b.

A static current for position calibration flows in the position correcting coil 7b, and the time variation di ₂ / dt of the current becomes almost zero. Therefore, as can be seen from the equation (4), almost no induced electromotive force e ₁ is generated in the vibration suppressing coil 7a. In other words, the position correcting current flowing through the position correcting coil 7b hardly influences the vibration suppressing control by the vibration suppressing coil 7a.

On the other hand, in the vibration suppressing coil 7a, a dynamic current for vibration suppression flows, and the time change di ₁ / dt of the current is large. Therefore, as can be seen from the formula (5), a large induced electromotive force e ₂ is generated in the position correcting coil 7b.

However, in the metal band stabilizer 1 according to the embodiment of the present invention, since the induction current countermeasure coil 13a is connected to the electric circuit of the position correcting coil 7b, the current generated by the induced electromotive force Is suppressed by the combined inductance of the position correcting coil 7b and the induction current countermeasure coil 13a.

5, since the position correcting coil 7b and the induction current countermeasure coil 13a are connected in series, the position correcting coil 7b, the induction current countermeasure coil 13a, The composite inductance L is expressed by the following equation.

L = L ₂ + L ₃ ... (7)

Here, L ₂ and L ₃ are inductances of the position correcting coil 7b and the induction current countermeasure coil 13a, respectively.

However, the reactance of the alternating current flowing through the coil is proportional to the frequency and the inductance of the alternating current. On the other hand, as described above, the vibration suppression signal is a signal containing a large amount of high frequency components, and the position correction signal is a signal including a lot of low frequency components. Therefore, the current induced from the vibration suppressing coil 7a to the position correcting coil 7b is a current including a large amount of high frequency components, which is greatly affected by the magnitude of the composite inductance L. On the other hand, the current flowing in the position correcting coil 7b is not greatly affected by the size of the composite inductance L. Moreover, as can be seen from the equation (7), even if the induction current countermeasure coil 13a is connected and the inductance L is large, the size of the inductance L ₂ of the position correcting coil 7b is The characteristics as an electromagnet by the position correcting coil 7b do not change.

The operation of the electromagnet becomes a first-order delay system as described above, and the time constant is given by equation (2). Therefore, the larger the composite inductance L is, the larger the time constant is and the current fluctuation can be suppressed. On the other hand, by increasing the number of turns of the induction current countermeasure coil 13a, the composite inductance L can be increased. However, when the number of turns is large, the size of the inductor coils 13a for induction current countermeasure becomes large, And the resistance of the entire circuit is increased, so that the load of the amplifier is increased.

Therefore, it is necessary to determine the inductance of the coil for the induction current control in consideration of the vibration control performance and the above disadvantages. According to the demonstration experiment of the effects of the embodiment of the present invention described later, the time series number of the series combination of the position correcting coil 7b and the induction current countermeasure coil 13a is set to be four to It is preferable to set it within the range of 10 times. The metal band stabilizer 1 according to the embodiment of the present invention is provided with the vibration suppressing coil 7a, the position correcting coil 7b, It is preferable that the coil 13a is designed to have the following range.

4L ₂ / R ₂ <(L ₂ + L ₃ ) / (R ₂ + R ₃ ) <10L ₂ / R ₂ (8)

L ₂ and L ₃ are inductances of the position correcting coil 7b and the inductive current countermeasure coil 13a respectively and R ₂ and R ₃ are inductance of the position correcting coil 7b and inductive current countermeasure And the resistance of the coil 13a.

Further, the provision of the induction current countermeasure coil 13a intentionally deteriorates the responsiveness of the position correcting coil 7b. However, as described above, since the position correcting coil 7b is not required to have responsiveness, there is no influence on the positional correction of the metal band. As a result, the mutual induced current between the vibration suppressing coil 7a and the position correcting coil 7b is suppressed to avoid an adverse influence on the vibration control, and the responsiveness of the vibration suppressing coil 7a, (7b) can be made compatible with each other.

Next, a configuration example in which the stabilizing device 1 for a metal band according to the embodiment of the present invention is arranged on a line for manufacturing a plated metal band will be described.

Fig. 6 is a schematic view showing a part of a production line of a general hot-dip coated metal band; Fig. In the production line of the hot-dip coated metal band shown in Fig. 6, the metal band 2 is conveyed from a previous step such as a cold rolling process, and is passed through an annealing furnace 14 maintained in an oxidizing or reducing atmosphere, The molten metal is cooled to about the same temperature as the temperature of the molten metal and is introduced into the molten metal bath 15.

In the molten metal bath 15, the metal bar 2 is passed through while immersing the molten metal, and molten metal adheres to the surface of the molten metal. Thereafter, the excess metal molten metal is smoothened by the gas ejected from the gas wiper 16 in the metal strip 2 drawn out from the molten metal bath 15, and the molten metal adhering amount is adjusted.

In the following process, for example, when the metal band 2 is used as an automotive outer plate, the alloy band 17 is used to reheat the metal band to form a homogeneous alloy layer The alloying treatment may be carried out. After passing through the cooling stand 18, the metal base 2 is subjected to special rustproofing and corrosion treatment in the chemical conversion treatment unit 19, wound by a coil, and shipped.

7 is an enlarged view of the vicinity of the gas wiper (broken line region in Fig. 6) of the production line of the molten plated metal band. 7, in the vicinity of the gas wiper 16 in the production line of the hot-dip coated metal band, the draw-in roller 20 draws the metal band 2 into the molten metal bath 15, And the pulling roller 21 pulls the metal band 2 out of the molten metal bath 15. The gas wiper 16 is disposed in the path line on the way that the pulling roller 21 lifts the metal band 2 and adjusts the deposition amount of the molten metal by eliminating the excess molten metal adhered to the metal band 2 do.

The electromagnets 3a and 3b and the non-contact displacement sensor 4 of the metal band stabilizer 1 according to the embodiment of the present invention are disposed in the pass line directly above the gas wiper 16, . By this arrangement, the distance between the gas wiper 16 and the metal base 2 becomes constant, and as a result, the pressure of the wiping gas becomes uniform, and the unevenness of the amount of the molten metal adhered to the metal base 2 can be suppressed .

Finally, a verification test of the effect of the stabilizing device 1 of the metal band according to the embodiment of the present invention will be described. Fig. 8 is a graph showing measured data by a stabilizing device for a metal band of a comparative example, and Fig. 9 is a graph showing measured data by a stabilizing device 1 for a metal band according to an embodiment of the present invention. 10 is a graph for comparing the magnitude of the noise included in the measurement data shown in FIG. 8 and the measurement data shown in FIG.

The graph shown in Fig. 8 is a graph showing the relationship between the vibration suppressing coil 7a and the vibration suppressing coil 7a when a vibration control command of a current 3A and a frequency of 10 Hz is given to the vibration suppressing coil 7a in the metal band stabilizer without using the inductive- And plotted current actual values when a control command of a constant current of 0 A is applied to the coil 7b. The current value of the vibration control command is also described in the graph shown in Fig.

As understood from the graph shown in Fig. 8, in the comparative example, a constant current of 0 A current flows in the position correcting coil 7b, but the actual value is detected as the actual value. The current flowing in the position correcting coil 7b is an induced current generated in the position correcting coil 7b by electromagnetic induction in which the fluctuation of the current for vibration control flowing in the vibration suppressing coil 7a is induced. 8, the induced current flowing in the position correcting coil 7b fluctuates, so that an induced current also flows on the side of the coil 7a for vibration suppression, and the disturbance .

The graph shown in Fig. 9 is a graph showing the relationship between the vibration control coil (7a) and the position correction coil (7a) by giving a vibration control command of current 3A and a frequency of 10 Hz to the vibration suppressing coil (7a) in the metal band stabilizer (1) 7b are given a control command of a constant current of 0A. The inductance of the induction current countermeasure coil 13a in this verification experiment is determined by the time constant of series combination of the position correcting coil 7b and the induction current countermeasure coil 13a, ). &Lt; / RTI &gt;

9, in the vibration suppressing coil 7a and the position correcting coil 7b according to the embodiment of the present invention, there is almost no influence by the induced current, Control is realized. As can be seen by comparing the graphs shown in Figs. 8 and 9, in the vibration suppressing coil 7a and the position correcting coil 7b in the comparative example, the position correcting coil 7b is induced The vibration suppressing coil 7a and the position correcting coil 7b according to the embodiment of the present invention are arranged such that the vibration suppressing coil 7a and There is no vicious cycle. As can be understood from the graph shown in Fig. 10, according to the metal band stabilizer 1 according to the embodiment of the present invention, it is possible to reduce the induction current which interferes with the vibration control to 1/11 times. That is, the metal band stabilizer 1 according to the embodiment of the present invention can avoid a reduction in the vibration suppressing ability due to the induced current between the vibration suppressing coil and the position correcting coil.

The metal band stabilizing device 1 according to the embodiment of the present invention is provided with the non-contact displacement sensor 4 for measuring the displacement of the metal band 2 during on-line travel, and the non- (5) for outputting a vibration suppression signal for suppressing the vibration of the metal band (2) and a position calibration signal for calibrating the position of the metal band (2) A position correcting coil 7b having a larger number of turns than the vibration suppressing coil 7a for generating a magnetic force in response to the position calibration signal outputted from the control unit 5, The vibration suppressing coil 7a and the position correcting coil 7b are wound concentrically and the magnetic force generated by the vibration suppressing coil 7a and the position correcting coil 7b is applied to the metal base 2 A core 6 for guiding the position correcting coil 7b, a core 6 for guiding the position correcting coil 7b, Since the induced current having a countermeasure coil (13a) for installation in, it is possible to avoid the degradation of the vibration-suppression capability by the induced currents between the coils for the vibration-suppression (7a) and a position correction coil (7b) for.

Here, the control unit 5 of the stabilizing device 1 for a metal band according to the embodiment of the present invention is configured such that the high-frequency component (the high-frequency component) is higher than the position calibration signal with respect to the deviation signal between the signal input from the non-contact displacement sensor 4 and the target value. And the position correction signal is outputted by performing an operation such that the gain of the low frequency component becomes larger than that of the vibration suppression signal. Therefore, it is possible to appropriately use the displacement correction amount for vibration suppression It is possible to distribute signals and appropriate signals used for position calibration. The control section 5 of the metal band stabilizing device 1 according to the embodiment of the present invention is configured such that the deviation signal of the signal inputted from the non-contact displacement sensor 4 and the target value It is preferable to output the position correction signal by outputting the vibration suppression signal by performing the PID control calculation with a larger setting and performing the PID control calculation with the setting of the integral gain larger than the vibration suppression signal.

The time constant of the series combination of the position correcting coil 7b and the induction current countermeasure coil 13a of the stabilizing device 1 of the metal band according to the embodiment of the present invention is the same as that of the position correcting coil 7b It is preferable that the thickness is designed to be in the range of 4 to 10 times. Alternatively, it is preferable that the position correcting coil 7b and the induction current countermeasure coil 13a of the metal band stabilizer 1 according to the embodiment of the present invention satisfy the following equation.

4L ₂ / R ₂ <(L ₂ + L ₃ ) / (R ₂ + R ₃ ) <10L ₂ / R ₂

L ₂ and L ₃ are inductances of the position correcting coil 7b and the inductive current countermeasure coil 13a respectively and R ₂ and R ₃ are inductance of the position correcting coil 7b and inductive current countermeasure And the resistance of the coil 13a.

The metal band stabilizing device 1 according to the embodiment of the present invention is a metal band stabilizing device 1 in which the vibration suppressing coil 7a, the position correcting coil 7b, The surface vibration suppressing coil 7a, the position correcting coil 7b and the core 6 and the backside vibration suppressing coil 7a, the position correcting coil 7b, (6), vibration and displacement to the front surface side and the back surface side of the metal base (2) can be suppressed.

The control unit 5 of the metal band stabilizing device 1 according to the embodiment of the present invention receives a signal from the non-contact displacement sensor 4 and outputs a vibration suppression signal for suppressing the vibration of the metal band 2, (8) for outputting a position correcting signal for calibrating the position of the pedestal (2), and a vibration suppressing signal outputted from the manipulated variable computing device (8) by a surface vibration suppressing coil (7a) And a position correcting signal output from the manipulated variable computing device 8 is supplied to the position correcting coil 7b for the surface and the position correcting coil 7a for the back surface, (10a) for supplying power to the surface-side vibration suppressing coil (7a) in accordance with the vibration suppressing signal for the surface distributed by the front-surface distributor (9a) And a position correcting signal for the surface distributed by the front and back distributor 9b, An amplifier 10b that feeds power to the position correcting coil 7b for the backside vibration suppressing coil 7a for power supply to the backside vibration suppressing coil 7a in accordance with the backside vibration suppression signal distributed by the front- The amplifier 10c is provided with an amplifier 10d that feeds power to the backside position correcting coil 7b in accordance with the backside position correcting signal distributed by the front and back distributor 9b, The coil 13a is connected to each of the electric circuits between the amplifier 10b and the surface position correcting coil 7b and between the amplifier 10d and the back position correcting coil 7b It is possible to suppress vibration and displacement to the front surface side and the back surface side of the metal table 2, respectively.

In the metal band stabilizing device 1 according to the embodiment of the present invention, since the magnetic circuit 13b of the inductive current countermeasure coil 13a is constituted as a closed circuit, it's difficult.

Further, a method of manufacturing a molten metal band according to an embodiment of the present invention includes a step of adhering a molten metal to a metal band 2 in a production line run, a step of removing excess molten metal adhering to the metal band 2 And the control step of controlling the vibration and the position of the metal band 2 by the stabilizing device 1 of the metal band in a noncontact manner, The pressure of the wiping gas becomes uniform, and it is possible to suppress the unevenness of the amount of the molten metal adhering to the metal base 2.

In addition, since the metal frame according to the embodiment of the present invention is manufactured by the above-described manufacturing method, it is possible to suppress the unevenness of the amount of deposited molten metal.

Although the present invention has been described based on the embodiments, the present invention is not limited to the description and drawings constituting a part of the present invention according to the present embodiment.

The present invention is useful for a line for producing a metal band, and is particularly suitable for a production line of a molten metal band.

1: Stabilizer of metal band
2: metal band
3a, 3b: Electromagnet
4: Non-contact displacement sensor
5:
6: Core
7a: Vibration suppressing coil
7b: position correcting coil
8:
9a, 9b: front and rear distributor
10a to 10d: Amplifier
11a and 11b:
12: input means
13a: coil for induction current countermeasure
13b: magnetic circuit
14: Annealing furnace
15: Molten metal bath
16: Gas wiper
17: Alloying furnace
18: Cooling zone
19: Mars processing unit
20: drawing roller
21: impression roller

Claims (8)

A non-contact displacement sensor for measuring the displacement of the metal band during on-
A controller for inputting a signal from the non-contact displacement sensor and outputting a vibration suppression signal for suppressing vibration of the metal band and a position calibration signal for calibrating a position of the metal band,
A first coil for generating a magnetic force in accordance with a vibration suppression signal outputted from the control unit,
A second coil generating a magnetic force in accordance with a position calibration signal output from the control unit, the second coil having a larger number of windings than the first coil,
A core wound around the first coil and the second coil concentrically and guiding a magnetic force generated by the first coil and the second coil to the metal,
And a third coil provided in series as an inductor in an electric circuit for feeding the second coil,
Wherein a current generated in the second coil is suppressed by induced electromotive force by the first coil due to a combined inductance of the second coil and the third coil. The method according to claim 1,
Wherein the control unit outputs the vibration suppression signal by performing an operation such that a gain of a high frequency component becomes larger than a deviation signal between the signal input from the non-contact displacement sensor and the target value, And the position calibration signal is outputted by performing an operation such that the gain of the low frequency component is larger than the suppression signal. The method according to claim 1,
Wherein the control section outputs the vibration suppression signal by performing a PID control calculation in which a differential gain between the signal input from the non-contact displacement sensor and the target value is greater than the position correction signal, And the position correction signal is output by performing a PID control calculation with an increase in the integral gain setting more than the vibration suppression signal. The method according to claim 1,
And the time constant of series combination of the second coil and the third coil is designed to be in the range of four times to ten times the time constant of the second coil. Device. The method according to claim 1,
The second coil, and the third coil satisfy the following equations.
4L ₂ / R ₂ <(L ₂ + L ₃ ) / (R ₂ + R ₃ ) <10L ₂ / R ₂
Here, L ₂ and L ₃ are the inductances of the second coil and the third coil, respectively, and R ₂ and R ₃ are the resistances of the second coil and the third coil, respectively. The method according to claim 1,
And the magnetic circuit of the third coil is configured as a closed circuit. An adhering step of adhering a molten metal to a metal band in a production line passage plate,
An adjusting step of adjusting an amount of molten metal adhered by a gas wiper that wipes excess molten metal adhered to the metal band;
A method for manufacturing a hot-dip coated metal band characterized by having a control step of non-contact controlling the vibration and position of the metal band by the stabilizing device of the metal band according to any one of claims 1 to 6. delete

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