JPH08243698A - Device for controlling fluidity of molten metal - Google Patents

Abstract

PURPOSE: To improve the consumable electric power efficiency and to stabilize the thrust by restraining heat generation of an electric magnet core in a linear motor caused by current. CONSTITUTION: An electric coil is wound around the electric magnet core 10 inserting laminated sheets 10b-10k with stainless steel outer sheets 10a, 101. Two sets of the linear motors notching the slits s11-s22 in each part and forming the tapered part at the tip part of tooth t11-t17 between slots are arranged at the upper part of a mold opening part so as to become the axial symmetry to a molten steel pouring nozzle.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flow control device for adjusting the flow rate of molten metal in a mold.

[0002]

2. Description of the Related Art In continuous casting, for example, molten steel is poured into a mold from a tundish, and in the mold, the molten steel is drawn from the wall surface of the mold while being gradually cooled. If the temperatures on the wall surfaces of the mold having the same height are not uniform, surface cracks and shell breakages are likely to occur. In order to improve this, conventionally, a linear motor is used to drive the molten steel to flow along the wall surface of the mold in the mold (for example, JP-A 1-228645).

When inserting the electric coil into the slot of the electromagnet core, the electric coil may be wound around the electromagnet core. This is because the width of the linear motor (x direction orthogonal to the thrust direction y) is made smaller by making the coil end project to the back surface of the electromagnet core in the direction opposite to the molten steel, and the slot is deepened so that the electric coil is inserted at its bottom. Then, it is effective to bring the tip surfaces (pole end surfaces) of the teeth between the slots close to and face the upper surface of the molten steel so that a strong electromagnetic force directly acts on the molten steel. Although the power factor is reduced by winding the body, a high electromagnetic force can obtain a large electromagnetic force with a small power source capacity.

[0004]

However, when the electric coil is wound around the electromagnet core and the driving time of the linear motor becomes long, the bottom of the slot and the coil end of the electromagnet core (extending from the slot and extending in the z direction). (The part toward the back surface of the core) and the edge portion facing the core generate heat. this is,
By winding the electric coil around the electromagnet core, the coil end becomes parallel (parallel to z) to the flat plate surface (y, z plane) of the electromagnet core, and the current flowing in the coil end causes the coil end in the x direction orthogonal to the flat plate surface. An alternating magnetic flux is generated, and an eddy current induced by this magnetic flux is generated in the flat plate surface, and the eddy current value along the edge of the core is high, which causes relatively high heat generation. Since the magnetic characteristics of the electromagnet core deteriorate as the temperature increases, the molten steel driving thrust of the linear motor decreases. Further, the resistance value increases due to the temperature rise of the electric coil, and the power loss increases. Thrust fluctuations due to these factors also disturb the flow velocity control of the molten metal.

A first object of the present invention is to suppress a thrust force fluctuation of a body wound linear motor, a second object is to suppress heat generation of an electromagnet core, and a third object is to reduce eddy current loss. To aim.

[0006]

The flow control device of the present invention is provided with an electromagnet core (10/20) having a plurality of slots extending in the x direction and distributed in the y direction; / 20), a plurality of electric coils (1Aa, 1Ba, 1Ca, 2Aa, 2Ba, 2Ca / 4Ab, mounted on the electromagnet core around the base (CST) extending in the y direction with the slot bottom (SBT). 4Bb, 4C
b, 5Ab, 5Bb, 5Cb); and energizing means (20F1 / 20) for applying an AC voltage having a phase difference to each of the electric coils to give thrust to the molten metal (MM) along the slot arrangement direction y.
L2); and the electromagnet core (10/20) is obtained by laminating an outer plate having a low magnetic permeability and a low electric conductivity on a thin plate laminate.
Those having slits (S11 to S22 / S31 to S42) extending in the x direction, and / or a taper (P14, P24 / P34, P44) that reduces the tooth cross section closer to the tips of the teeth between the slots. Is the one that has.

One embodiment of the present invention is a mold comprising a pair of long sides (5F, 5L) extending in the y direction and facing each other and a pair of short sides (4R, 4L) extending in the x direction and facing each other. A thin plate laminate having a plurality of first set slots extending in the x direction and distributed along one pair of long sides (5F) and a first set of slits (S11 to S22) extending in the x direction. Is an electromagnet core in which outer plates with lower magnetic permeability and lower conductivity are laminated, and the tips of the teeth between the slots face the upper surface of the molten metal in the mold at a position near one of the pair of short sides (4R). The first electromagnet core (1
0); inserted into the first set of slots, the first electromagnet core (10)
Of the slot bottom (SBT) is attached to the first electromagnet core (10) with a body winding that wraps around the base (CST) extending in the y direction, and a part of it is located above the upper end surface of the one long side (5F). A plurality of electric coils of the first set (1Aa, 1Ba, 1Ca, 2Aa, 2Ba, 2C
a); first energizing means (20F1) for applying an AC voltage having a phase difference for applying a thrust along the array direction y of the first set of slots to the molten metal to each of the first set of electric coils; The thin plate laminate further has a plurality of second set slots extending in the x direction and a second set of slits (S31 to S42) distributed along the other (5L) of the long sides of the pair and extending in the x direction. An electromagnet core having a laminate of outer plates having low magnetic permeability and low conductivity,
The second electromagnet core (20); the second set of the second set, in which the tips of the teeth between the slots face the upper surface of the molten metal in the mold at a position close to the other (4L) of the pair of short sides and are in the mold opening. The second electromagnet core (20) is inserted into the slot, and is attached to the second electromagnet core (20) by a body winding that surrounds the base (CST) of the second electromagnet core (20) that extends in the y direction having the slot bottom (SBT), and a part of the other is attached to the other. A plurality of second sets of electric coils located above the upper end surface of the long side (5 L)
(4Ab, 4Bb, 4Cb, 5Ab, 5Bb, 5Cb); and an AC voltage having a phase difference for applying thrust to the molten metal along the arrangement direction y of the slots of the second set, to each of the electric coils of the second set. The second energizing means (20L2) for applying to the. The outer plate is a stainless plate, and the slits are tooth end slits (s11 to
s15 / s31 to s35), slot bottom slits (s16 to s19 / S36 to s39) extending from the bottom of the slot (SBT) in the z direction, and the back surface of the electromagnet core extending in the z direction from the back surface facing the bottom of the slot. It is a slit (s20-s22 / s40-s42).

In order to facilitate understanding, the symbols of the corresponding elements of the embodiment shown in the drawings and described later are given in parentheses.
It is added for reference.

[0009]

FIG. 1 shows the arrangement of a linear motor in a continuous casting mold according to an embodiment of the present invention. 5F and 5 in the figure
L is the first and second long pieces of the continuous casting mold, 6R and 6L are the first and second short pieces, and the molten steel is passed through the injection nozzle 30 into the space surrounded by them from the front side to the back side of FIG. (From top to bottom in the vertical direction z). Each side (5F, 5L, 6R, 6L) is a copper plate 1F,
1L, 3R, 3L, non-magnetic stainless steel plate 2F, 2L,
4R and 4L are backed. A stainless cover plate is placed on the upper end surface of each side of the mold as shown in FIG. 3, but the illustration is omitted in FIGS. 1 and 2.

In this embodiment, the molds (5F, 5L, 6
R, 6L), the first and second electromagnet cores 10 and 20 are arranged diagonally about the injection nozzle 30 so as to face the upper surface of the molten steel in the mold. . These are three-phase linear motors, and the first electromagnet core 10 drives the molten steel from the right to the left (in the direction from + y to -y) along the long piece 5F, and the second electromagnet core 20.
Drives the molten steel from left to right along the long piece 5F.

FIG. 2A shows an enlarged vertical section of the first electromagnet core 10 (enlarged section 2A-2A in FIG. 1).
FIG. 3B shows an enlarged vertical cross section of the second electromagnet core 10, and FIGS. 3A and 3B show enlarged horizontal cross sections of the electromagnet core 10 (lines 3A-3A and 3B-3B in FIG. 2). (Enlarged cross section)
Indicates. Dimension leader line (dashed line) in these drawings
Small numbers in between indicate dimensional values (mm). The first linear motor including the first electromagnet core 10 and the second linear motor including the second electromagnet core 20 have the same size and the same electric rating, and the nozzle 30 located at the center position of the mold opening. Are arranged symmetrically with respect to.

With reference to FIGS. 1 to 3, in this embodiment, the electromagnet core 10 is long in the y direction, and the longitudinal direction y
A large number of thin steel plates having a comb-shaped flat plate surface in which six notches for slots are formed at equal pitches (these group sections are 10b to 10k; hereinafter, one unit of the group section is referred to as a plate. ) Are laminated. On the outer surfaces of the thin steel plates 10b to 10k, outer plates (stainless steel plates) 10a and 10l, which are comb-shaped like the thin steel plates, are stacked, and the outer plates 10a and 10l sandwich the thin steel plates 10b to 10k. The thin steel plate (hereinafter, referred to as a laminated plate) is protected.

The electromagnet core 10 has six slots, and the electric coils 1Aa to 2Ca are inserted into the respective slots, and these electric coils 1Aa to 2Ca circulate around the base portion CST of the electromagnet core 10. That is, the electric coil is a body winding. Although the electromagnet core 10 and the electric coils 1Aa to 2Ca are cooled and covered with a heat-resistant cover, the cooling structure and the cover are not shown. The electromagnet core 10 has a comb shape having a slot extending in the x direction on the lower surface, an electric coil is inserted into each slot, and the lower end surfaces of the teeth t11 to t17 between the slots are magnetic pole end surfaces, and the continuous casting mold (5F, 5L , 6R, 6L) to face the upper surface of the molten steel, and the tips of the teeth t11 to t17 suppress the disturbance of the magnetic field due to the edge (sharpness) (which causes eddy currents and heat generation). , Taper inclined with respect to x-axis and z-axis (P14, P24: FIG. 3)
Has become. Due to the presence of the tapers (P14, P24), the magnetic field is concentrated in the center of the tip surfaces of the teeth t11 to t17, the magnetic field is less disturbed, and heat generation is less.

The electromagnet core 10 also includes tooth end slits s11 to s15 extending in the z direction from the tip surfaces of the teeth t11 to t17 between the slots, slot bottom slits s16 to s19 extending in the z direction from the bottom SBT of the slot, and Back slits s20 to s22 extending in the z direction from the back surface of the electromagnet core facing the bottom SBT of the slot are cut. These slits are for blocking eddy currents that flow in a ring shape on the y and z planes (planes orthogonal to the x axis), and are both substantially parallel to the x axis and the y axis. The stainless steel outer plates 10a and 10l and the laminate plates 10b to 10k between them are entirely traversed.

Two sides (coil ends) of the electric coils 1Aa to 2Ca inserted into the respective slots of the electromagnet core 10.
Extends in the z direction in the outer space of the outer plates 10a and 10l and faces the upper plane of the electromagnet core 10 (the rear surface with respect to the plane in which the slots are cut). That is, the electric coils 1Aa to 2C
“A” is “wrapped around” the electromagnet core 10. Since the coil ends extend in the outer space of the outer plates 10a and 10l in the z direction, a circular alternating magnetic flux centered on the coil ends (z axis) is generated around each coil end according to the right-handed screw law, and this alternating The magnetic flux enters the electromagnet core 10 substantially perpendicularly to the outer surfaces of the stainless steel outer plates 10a and 10l. The stainless steel outer plates 10a and 10l of the electromagnet core 10 and the laminar plates 10b to 10k between them are centered on the alternating magnetic flux (x axis) and extend along the plate surface of each plate (on the plate surface). -Circulating alternating current (eddy current) is induced,
Due to the jule heat, each plate generates heat. In order to efficiently generate thrust, the linear motor has 1
A high frequency current of 0 Hz or more, for example 50 Hz is applied, but the eddy current value is large at the edge of the core due to the high frequency skin effect,
Edges easily generate heat. The above-mentioned tooth end slits s11 to s
15, the slot bottom slits s16 to s19, and the back surface slits s20 to s22 are all cut from the edge (end face) toward the inside of the core, so that the eddy current at the edge portion is suppressed or cut off. Heat generation is reduced.

FIG. 2B shows an enlarged vertical section of the second electromagnet core 20 (enlarged section taken along line 2B-2B in FIG. 1). The electromagnet core 20 also has a structure similar to that of 10, and is positioned with respect to the long side 5L and the short side 6L, similar to the positional relationship of the first electromagnet core 10 with respect to the long side 5F and the short side 6R.

FIG. 8A shows a computer simulation result of the temperature distribution of the electromagnet core 10 when the linear motor is driven without slits (comparative example), and FIG. The computer simulation result of the temperature distribution of the electromagnet core 10 when the linear motor is driven in a state where the end slits s11 to s15 and the slot bottom slits s16 to s19 are inserted is shown. This is shown in FIG.
It is a sectional view corresponding to. From FIG. 8, when the linear motor is driven without slits, the temperature rises at the bottom SBT of the slot and the back surface of the core.
It is presumed that this temperature rise deteriorates the magnetic characteristics of the core and increases the resistance value of the electric coil, and thus lowers the power efficiency of the coil body winding linear motor. However, FIG.
As shown in (b), by inserting the tooth end slits s11 to s15 and the slot bottom slits s16 to s19, the surface temperature of the core edge portion is lowered. Since the eddy current bypasses the slit, heat is concentrated at the bottom of the slit. However, since the bypass loop is long and its resistance value is high, the amount of heat generated is small and the energy loss is small as a whole.

Further, FIG. 9 shows an outer plate 10a and a laminated plate 10 when stainless plates are used for the outer plates 10a and 10l.
b and 10c, the temperature distributions of the outer plates 10a and 10b and the laminate plate 10c when a Cu plate is used as the outer plate (Comparative Example 1) are shown in FIG. Outer plates 10a and 10b when a Cu plate is used (Comparative Example 2)
And the temperature distribution of the laminate 10c (both simulation results by computer). By stacking an outer plate (stainless steel) with low permeability and low conductivity on the surface of the electromagnet core, magnetic flux in the direction perpendicular to the outer plate surface is suppressed from entering the core, and the inside of the teeth between the slots is suppressed. The eddy current is suppressed and the temperature of the tooth is lowered. This is shown in FIG. 9 (c). That is, when a laminated body made of only a Fe laminate plate (for example, an electromagnetic steel plate) is used as an electromagnet core, or when a good conductor outer plate is applied (Figs. 1 and 1).
It is possible to prevent an increase in temperature as compared with (c) of 1).
According to this finding, in the above-mentioned embodiment, the outer plates 10a, 10
A stainless plate is used for l.

As shown in FIGS. 9 to 11 (b) and (c), in the laminate plates (10b, 10c), the temperature rises greatly at the tips of the teeth between the slots. The tooth end slits s11 to s15 of the above-described embodiment are provided to suppress this temperature rise, and suppress or block the eddy current at the tip of the tooth between the slots, so that heat generation at the tooth tip is reduced. .

FIG. 4 shows the connection of the electric coils 1Aa to 2Ca and 4Ab to 5Cb shown in FIGS. 2A and 2B and the connection with the power supply circuit. This connection has two poles, and three-phase alternating current is applied to the electric coil. For example, the electric coils 1Aa to 2Ca have u, V, and
It is represented as w, U, v, W. And "U" is the positive phase energization of the U phase of the three-phase AC (as it is), and "u" is U
Represents the reverse phase energization (phase energization 180 degrees from the U phase), and the U phase is applied to the winding start end of the electric coil "U", while the winding is wound on the electric coil "u". This means that the U phase is applied at the end. Similarly, "V" is 3
Phase alternating current V phase positive phase energization, "v" is V phase reverse phase energization, "W" is three phase AC W phase positive phase energization, and "w" is W
Indicates the reverse phase energization of a phase. Terminals U11 and V11 shown in FIG.
And W11 are power supply connection terminals of the electric coils 1Aa to 2Ca, and terminals U12, V12 and W12 are power supply connection terminals of the electric coils 4Ab to 5Cb.

FIG. 5 shows a power supply circuit 20F1 for supplying a three-phase alternating current to the electric coils 1Aa to 2Ca. 3-phase AC power supply (3
Phase power line) 21 is a thyristor bridge 2 for DC rectification
2A1 is connected, and its output (pulsating current) is smoothed by the inductor 25A1 and the capacitor 26A1. The smoothed DC voltage is applied to the power transistor bridge 27A1 for forming a three-phase AC, and the U-phase of the three-phase AC output from the power-transistor bridge 27A1 is supplied to the power connection terminal U11 shown in FIG. , And W phase is the power supply connection terminal W11
Is applied to

A coil voltage command value VdcA1 for generating thrust for causing the electric coils 1Aa to 2Ca to generate a circulating flow along the long side of the continuous casting mold is given to the phase angle α calculator 24A1 and the phase angle α calculator 24A1. However, the conduction phase angle α corresponding to the command value VdcA1 (50 Hz in the Siris embodiment)
, A constant voltage three-phase AC signal is generated and given to the comparator 29A1. The comparator 29A1 also includes a triangular wave generator 30A.
1 gives a constant voltage triangular wave of 3 KHz. Comparator 29A
1 is a high level H (transistor on) when the U-phase signal is at a positive level and is higher than the triangular wave level provided by the triangular wave generator 30A1, and a low level L (transistor off) when the U-phase signal is less than the triangular wave level. To the positive section of the U phase (to the U phase positive voltage output transistor).
When the U-phase signal is at a negative level, it is a high level H when it is below the level of the triangular wave provided by the triangular wave generator 30A1, and a low level L signal when it exceeds the level of the triangular wave. Gate driver 28A to the negative section (to the U-phase negative voltage output transistor)
Output to 1. The same applies to the V-phase signal and the W-phase signal. The gate driver 28A1 is provided for each phase, positive,
Transistor bridge 27 corresponding to the signal to the negative section
Each transistor of A1 is energized on and off.

As a result, the power supply connection terminal U11 has three terminals.
A U-phase voltage of phase alternating current is output, a similar V-phase voltage is output to the power supply connection terminal V11, and a similar W-phase voltage is output to the power supply connection terminal W11. The inter-curve level is determined by the coil voltage command value VdcA1.
The frequency of the three-phase voltage is the frequency command value F in this embodiment.
It is 50 Hz by dc. That is, the peak voltage value (thrust) specified by the coil voltage command value VdcA1 is 50 Hz.
The three-phase AC voltage of the electric coil 1A shown in FIGS.
a to 2Ca.

FIG. 6 shows a power supply circuit 20L2 for supplying a three-phase alternating current to the electric coils 4Ab to 5Cb. This power circuit 20
The configuration of L2 is the same as that of 20F1 described above, but the coil voltage command value (VdcB2) is different.

That is, the coil voltage command value VdcB2 for generating the thrust that causes the electric coils 4Ab to 5Cb to cause the circulating flow along the long side of the continuous casting mold is the phase angle α calculator 2.
Given to 4B. These coil voltage command values VdcA1
(FIG. 5) and the coil voltage command value VdcB2 (FIG. 6)
The computer 43 shown in FIG. 7 supplies each of the power supply circuits 20F1 and 20L2.

FIG. 7 shows the mold short pieces 6L and 6 shown in FIG.
The back of R is shown. In these short pieces 6L, 6R, thermocouples S31 to S3n and S41 to S4n are arranged at equal intervals in one row in the slab drawing direction (height direction z; vertical direction), and each thermocouple is The temperature of the inside of the copper plate (on the surface that contacts molten steel) is detected by penetrating the backing stainless steel plate. The signal processing circuits 41A and 41B generate an analog signal (detection signal) representing the temperature detected by the thermocouple and apply it to the analog gate 42.

The computer 43 is an analog gate 42.
To control thermocouples S31 to S3n and S41 to S4.
n detection signals are sequentially selected, A / D converted and read,
By the high temperature value extraction process 44, the highest temperature value Tm1L1 and the next highest temperature value Tm2L1 among the detection temperatures of the thermocouples S31 to S3n are extracted, and the highest temperature value Tm1R1 of the detection temperatures of the thermocouples S41 to S4n. And the next highest temperature value Tm2R1. Then, the representative temperature (Tm1L1-Tm2L1) × 0.7 + TM2L1 of the short piece 6L is calculated, the representative temperature (Tm1R1-Tm2R1) × 0.7 + TM2R1 of the short piece 6R is calculated, and the difference between them, that is, the representative between the short pieces 6L and 6R. Temperature difference (Tm1L1-Tm2L1) × 0.7 + TM2L1-(Tm1R1-Tm2R1) × 0.7-T
When M2R1 is calculated and is a positive value (0 or more) (the temperature of the short piece 6R is higher), VdcA1 = representative temperature difference ×
A (A is a coefficient) is calculated, and VdcB2 = B-VdcA
Calculate 1. When the representative temperature difference is a negative value (the temperature of the short piece 15L is higher), VdcB2 = −representative temperature difference ×
A is calculated, and VdcA1 = B−VdcB2 is calculated.

VdcA1 is an electric coil 1A on the short piece 6R side.
a to 2Ca (FIG. 4) is a current level (thrust) command value, and VdcB2 is an electric coil 4Ab to 5B on the short piece 6L side.
It is a current level (thrust) with respect to Cb (FIG. 4). When the representative temperature difference is a positive value (the temperature of the short piece 6R is higher), these command values increase the three-phase AC current level flowing in the electric coils of the electric coils 1Aa to 2Ca to increase the strong thrust (dotted line arrow in FIG. 1). ) To reduce the phase AC current level flowing in the electric coils 4Ab to 5Cb to weaken the thrust, and conversely,
When the representative temperature difference is a negative value (the temperature of the short piece 6L is higher), the three-phase AC current level flowing in the electric coils 4Ab to 5Cb is increased to apply a strong thrust to the electric coils 1Aa to 2A.
This means that the three-phase AC current level flowing Ca is reduced to weaken the thrust.

When the molten steel flow flowing from the nozzle 30 into the mold is substantially symmetrical with respect to the nozzle 30, the short pieces 6R and 6L are formed.
Are substantially the same and the surface layer flow is symmetrical with respect to the nozzle 30, and in this case, VdcA1 = VdcB2, and the electric coils 1Aa to 2Ca and the short piece 6R on the short piece 6R side.
The energization levels of the L-side electric coils 4Ab to 5Cb are substantially equal, and the first electromagnet core 10 and the second electromagnet core 20 are
As shown by the dotted arrows in FIG. 1, thrusts of substantially equal strength but opposite directions are given to the molten steel. As a result, the actual superficial flow of the molten steel is such that the superficial flow due to the projecting flow from the nozzle 30, which is in the same direction as the circulating flow, is enlarged, and the superficial flow in the opposite direction to the circulating flow is canceled, Creates a circulating flow on the surface of molten steel. As a result, the floating of the bubbles is promoted, the powder is not caught in the molten steel, the inner surface of the mold near the surface layer is wiped clean, and the molten steel does not stay.
Uniform temperature distribution of molten steel in the mold.

In order to obtain a product of stable quality, it is necessary to stabilize the thrust of the linear motor in order to stably induce the circulating flow as described above. The decrease in thrust due to temperature rise becomes a problem.

Since the linear motor is of a "body-wound" type, it is easy to install it on the upper part of the mold, especially on the upper part of the mold with a narrow upper opening width, and as described above, a circulating flow is induced in the molten steel. can do.

The electromagnet cores 10 and 20 are made of a stainless steel outer plate having a low magnetic permeability and a low electric conductivity so as to suppress a magnetic flux entering from the outside of the core to the inside of the core perpendicular to the flat plate surface of the laminating plate. Since the plates are sandwiched, the lamination plate is mechanically protected, and the internal heat generation of the teeth between the slots is reduced (FIG. 9 (c)), whereby the core (especially the magnetic pole) is formed. Deterioration of the magnetic characteristics of the teeth is suppressed, and the power consumption efficiency of the linear motor is improved. Especially, the effect is high when the linear motor is driven at a high frequency.

The tooth end slit S is formed on the electromagnet cores 10 and 20.
11 to S15, S31 to S35, slot bottom slit S
16-S19, S36-S39 and back slit S2
Since 0 to S22 and S40 to S42 are cut, eddy currents at the tips of the teeth between the slots, the bottom of the slots and the back surface of the core are suppressed, and the heat generation of the respective parts is reduced, thereby reducing the resistance value of the electric coil. The increase and the deterioration of the core magnetic characteristics are suppressed, and the power consumption efficiency of the linear motor is improved. Especially, the effect is high when the linear motor is driven at a high frequency.

Teeth t between the slots of the electromagnet cores 10 and 20.
Tapers P14, P24 / which reduce the horizontal tooth cross section toward the tip of 11 to t17 and t21 to t27
Since P34 and P44 are formed, the magnetic field is generated by the teeth t11 to t11.
Concentrated at the center of the tip surface of t17, t21 to t27, the disturbance of the electric field near the tooth tip edge portion is small, the eddy current due to the disturbance is suppressed, and the heat generation at the tooth tip is reduced.

[Brief description of drawings]

FIG. 1 is a plan view showing an arrangement of electromagnet cores and electric coils above a surface of molten steel of a continuous casting mold according to an embodiment of the present invention.

FIG. 2 is an enlarged vertical sectional view of electromagnet cores 10 and 20 shown in FIG.

3 is an enlarged cross-sectional view of the electromagnet cores 10 and 20 shown in FIG.

4 is an electric circuit diagram showing a connection mode of the electric coil shown in FIG. 2 and a connection with a power supply circuit.

FIG. 5 shows electric coils 1Aa to 2C shown in FIG.
It is an electric circuit diagram which shows the power supply circuit which applies a three-phase alternating current voltage to a.

FIG. 6 shows electric coils 4Ab to 5C shown in FIG.
It is an electric circuit diagram which shows the power supply circuit which applies three-phase alternating current to b.

7 is a block diagram showing the electric circuits connected to the backs of the short pieces 6L and 6R of the casting mold shown in FIG. 1 and the thermocouples provided therein.

8 (a) is a plan view showing a temperature distribution of the outer plate 10a shown in FIG. 2 when the linear motor is driven without slits in the electromagnet core 10, and FIG. 8 (b) is an electromagnet core. 3 is a plan view showing a temperature distribution of an outer plate 10a shown in FIG. 2 when a linear motor is driven in a state where slits are provided in 10.

FIG. 9A is a plan view showing a temperature distribution of the outer plate 10a when a stainless plate is used for the outer plate 10a,
(B) is a plan view showing a temperature distribution of the laminated plate 10b when a stainless plate is used as the outer plate 10a, (c).
FIG. 6 is a plan view showing a temperature distribution of a laminate plate 10c when a stainless plate is used for the outer plate 10a.

10A is a plan view showing a temperature distribution of the outer plate 10a when a Cu plate is used for the outer plate 10a, and FIG. 10B is a laminated plate 10b when a Cu plate is used for the outer plate 10a.
3C is a plan view showing the temperature distribution of FIG. 3C, and FIG. 6C is a plan view showing the temperature distribution of the laminate plate 10c when a Cu plate is used as the outer plate 10a.

FIG. 11A is a plan view showing a temperature distribution of the outer plate 10a when a B (brass) plate is used for the outer plate 10a,
(B) is a plan view showing a temperature distribution of the laminated plate 10b when a B (brass) plate is used as the outer plate 10a, (c).
[Fig. 4] is a plan view showing a temperature distribution of a laminate plate 10c when a B (brass) plate is used for the outer plate 10a.

[Explanation of symbols]

1F, 1L, 3R, 3L: Copper plate 2F, 2L, 4R, 4L: Non-magnetic stainless steel plate 5F, 5L: Long piece 6R, 6L: Short piece 10, 20: Electromagnetic core 10a, 10l:
Outer plate 10b-k: Laminate plate 20b-l: Laminate plate 30: Injection nozzle 20F1, 20L
2: Power supply circuit MM: Molten steel PW: Powder SBT: Slot bottom CST: Core base t11 to t17, t21 to t27: Tooth s11 to s22, s31 to s42: Slit P14, P24, P34, P44: Tape 1Aa, 1Ba, 1Ca, 2Aa, 2Ba, 2Ca: Electric coil 4Ab, 4Bb, 4Cb, 5Ab, 5Bb, 5Cb: Electric coil U11, V11, W11 / U12, V12, W12: Power supply connection terminal

Claims (12)

[Claims] 1. An electromagnet core having a plurality of slots extending in the x-direction and distributed in the y-direction, wherein an outer plate having a lower magnetic permeability and a lower electric conductivity is further laminated on a thin plate laminated body;
A plurality of electric coils mounted on the electromagnet core around the base of the electromagnet core extending in the y direction having the slot bottom; and a phase difference for giving thrust to the molten metal along the slot arrangement direction y. A flow control device for molten metal, comprising: an energizing means for applying a certain AC voltage to each of the electric coils. 2. An electromagnet core having a plurality of slots extending in the x-direction and distributed in the y-direction and slits extending in the x-direction; inserted into the slot and circling a base portion of the electromagnet core extending in the y-direction having a slot bottom. A plurality of electric coils mounted on the electromagnet core; and energizing means for applying an AC voltage having a phase difference for applying a thrust along the slot arrangement direction y to the molten metal to each of the electric coils. Molten metal flow control device. 3. A thin plate laminate having a plurality of slots extending in the x direction and distributed in the y direction, and having a taper at the tip of the teeth between the slots, the cross section of the tooth becoming smaller toward the tip surface. An electromagnet core; a plurality of electric coils that are inserted into the slots and are attached to the electromagnet core by orbiting the base of the electromagnet core that extends in the y direction having the slot bottom; and thrust force along the slot arrangement direction y. A flow control device for molten metal, comprising: an energizing means for applying an alternating voltage having a phase difference to the molten metal to each of the electric coils. 4. An electromagnet core comprising a plurality of slots extending in the x-direction and distributed in the y-direction and slits extending in the x-direction, and an outer plate having a low magnetic permeability and a low electrical conductivity laminated on a thin plate laminate; a slot. A plurality of electric coils that are inserted into the electromagnet core and are mounted on the electromagnet core around the base of the electromagnet core that extends in the y direction with the bottom of the slot; and to apply thrust to the molten metal along the arrangement direction y of the slots. A flow control device for molten metal, comprising: energizing means for applying an AC voltage having a phase difference to each of the electric coils. 5. A thin plate laminate having a plurality of slots extending in the x direction and distributed in the y direction, and having a taper at the tip of the teeth between the slots, the cross section of the tooth becoming smaller toward the tip surface. An electromagnet core further laminated with an outer plate having a low magnetic permeability and a low electric conductivity; a plurality of electromagnet cores that are inserted into the slots and are mounted on the electromagnet cores around the base of the electromagnet core that extends in the y direction with the slot bottom. A molten metal flow control device comprising: an electric coil; and an energizing means for applying an AC voltage having a phase difference for applying a thrust force along the slot arrangement direction y to the molten metal to each of the electric coils. 6. A taper having a plurality of slots extending in the x-direction and distributed in the y-direction and slits extending in the x-direction, with the tooth cross-sections being made smaller at the tips of the teeth between the slots as they are closer to the tips. An electromagnet core having: a plurality of electric coils inserted into the slot and mounted on the electromagnet core around a base of the electromagnet core extending in the y direction having a slot bottom;
And a flow control device for the molten metal, comprising: energizing means for applying an AC voltage having a phase difference for applying thrust to the molten metal along the slot arrangement direction y to each of the electric coils. 7. A taper having a plurality of slots extending in the x-direction and distributed in the y-direction and slits extending in the x-direction, and the tooth cross-sections are made smaller at the tips of the teeth between the slots as they are closer to the tips. An electromagnet core in which an outer plate having a low magnetic permeability and a low electrical conductivity is further laminated on a thin plate laminate having: a slotted bottom of the electromagnet core extending in the y direction and attached to the electromagnet core. Flow control of molten metal; a plurality of electric coils; and energizing means for applying an AC voltage having a phase difference for applying thrust to the molten metal along the array direction y of the slots to each of the electric coils apparatus. 8. A mold having a pair of long sides extending in the y direction and facing each other and a pair of short sides extending in the x direction and facing each other, and distributed along one of the pair of long sides in the x direction. What is claimed is: 1. An electromagnet core comprising a plurality of first set slots extending and a first set slit extending in the x direction, wherein an outer plate having a lower magnetic permeability and a lower electrical conductivity is further laminated on a thin plate laminate, A first electromagnet core having tooth tips facing the upper surface of the molten metal in the mold at a position close to one of the pair of short sides and within the mold opening;
The first electromagnet core is inserted into a pair of slots, and is attached to the first electromagnet core by a body winding that wraps around a base portion of the first electromagnet core that extends in the y direction and has a slot bottom. A part of the first electromagnet core is located above the upper end surface of the one long side. A plurality of first sets of electric coils; first
First energizing means for applying an AC voltage having a phase difference for applying thrust to the molten metal along the arrangement direction y of the pair of slots to each of the first set of electric coils; along the other of the pair of long sides An electromagnet core having a plurality of second sets of slots distributed in the x direction and a second set of slits extending in the x direction, and an outer plate having a lower magnetic permeability and a lower electric conductivity, which is further laminated on a thin plate laminate. And the tips of the teeth between the slots face the upper surface of the molten metal in the mold at a position close to the other of the pair of short sides and are in the mold opening; a second electromagnet core; inserted into a second set of slots A plurality of first electromagnet cores, which are attached to the second electromagnet core by a body winding that surrounds a base portion having a slot bottom and extending in the y direction, and a part of which is located above the upper end surface of the other long side. Two sets of electric coils; and a second set of slots Flow control device for molten metal, comprising: second energizing means for applying an AC voltage having a phase difference for applying a thrust force along the arrangement direction y to the molten metal to each of the second set of electric coils. 9. The molten metal flow control device according to claim 1, claim 4, claim 5, claim 7, or claim 8, wherein the outer plate is a stainless plate. 10. The molten metal of claim 2, claim 4, claim 6, claim 7 or claim 8, wherein the slit includes a tooth end slit extending in the z direction from the tip surface of the tooth between the slots. Flow control device. 11. The molten metal of claim 2, claim 4, claim 6, claim 7, claim 8 or claim 10, wherein the slit comprises a slot bottom slit extending in the z-direction from the bottom of the slot. Flow control device. 12. The slit includes a back slit extending in the z direction from a back surface of the electromagnet core facing the bottom of the slot, claim 2, claim 4, claim 6, claim 7, claim 8, and claim 9. The molten metal flow control device according to claim 10 or 11.