JPH0814762A - Molten metal retaining device - Google Patents

Abstract

PURPOSE:To provide a molten metal retaining device which can reduce the interior flow of the molten metal to stably retain the molten metal. CONSTITUTION:In a molten metal retaining device wherein, at the lower end part of a molten metal 7 to be retained, an alternating magnetic flux is produced in a horizontal direction using an exciting coil 2 and the molten metal 7 is retained in the air by the electromagnetic force 11, a circuit 3 is added to apply superimposed DC current to the exciting coil 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for holding molten metal in the air. In addition, it can be applied to a molten metal electromagnetic valve, a molten metal plating device, a high melting point metal levitation / melting device, or a high-purity metal melting / levitation device.

[0002]

2. Description of the Related Art A conventional molten metal holding device is shown in FIG.
As shown in the figure, an exciting coil 2 is wound around the iron core 1, and an alternating current is supplied to the exciting coil 2 from an alternating current power source 3, so that an alternating magnetic flux is generated between the two magnetic poles 4 and 5 of the iron core 1. 9 occurs in the x direction, which is the horizontal direction in the figure. Between the magnetic poles 4 and 5, the lower end of the upper and lower opening container 6 which is opened at the top and bottom is located. The upper and lower open containers 6
It is made of a heat-resistant insulator, and the molten metal 7 is arranged inside the insulator.

Therefore, an induced current 10 is generated in the molten metal 7 by the alternating magnetic flux 9 in the y-axis direction, which is the direction perpendicular to the paper surface of the figure, and the interaction between the induced current 10 and the alternating magnetic flux 9 pushes up. The electromagnetic force 11 acts in the z-axis direction, which is the upper side in the figure, according to Fleming's left-hand rule. Thereby, the molten metal 7 is held in the air.

[0004]

In the conventional molten metal holding device shown in FIG. 6, for example, when an induced current 10 in the molten metal 7 flows in the positive direction of the y-axis which is the front side in the direction perpendicular to the paper surface in the figure. The alternating magnetic flux 9 flowing in the positive direction of the x axis, which is the right direction in the figure, is curved downward in the z axis. Therefore, the pushing-up electromagnetic force 11 inclines from the positive direction of the z-axis, which is the upper side in the figure, and a compressive force 13, which is a component force in the horizontal direction of the x-axis, is generated.

As a result, the molten metal 7 which has received the compressive force 13
Flows to the front side or the back side, which is the direction perpendicular to the paper surface of the figure,
The molten metal holding surface became wavy in the y-axis direction and became unstable, and holding of the molten metal 7 was incomplete. The present invention has been made in view of the above prior art, and an object of the present invention is to provide a molten metal holding device capable of reducing the flow inside the molten metal and stably holding the molten metal.

[0006]

The structure of the present invention which achieves such an object is to generate an alternating magnetic flux in the horizontal direction by using an exciting coil at the lower end portion of the molten metal to be held, and to generate the above-mentioned electromagnetic force. In a molten metal holding device for holding molten metal in the air, a circuit for superimposing a DC current on the exciting coil is attached, or a device for applying a DC magnetic flux to the molten metal is attached. And

[0007]

As shown in FIG. 1, when an alternating current is applied to the exciting coil 2 and a direct current is applied from the direct current power supply 17, the excitation of the waveform in which the direct current is superimposed on the alternating current as shown in FIG. A current 18 flows through the exciting coil 2. When such an exciting current 18 flows through the exciting coil 2, an alternating magnetic flux 9 having a waveform including a DC component 19 as shown in FIG. 3 is generated between the magnetic poles 4 and 5.

Since the alternating current component of the alternating magnetic flux 9 is attenuated in the surface layer of the molten metal 7, the direct current component 19 acts strongly inside the molten metal 7. Therefore, the molten metal 7 which is a conductor
Flows in a direction traversing the magnetic flux 9, that is, in the y-axis direction or the z-axis direction, an induced current 10 flows in the molten metal 7, and the interaction force between the induced current 10 and the DC component 19 of the alternating magnetic flux 9 suppresses the flow. The molten metal 7 is stably held because the molten metal 7 works in the direction.

Further, as shown in FIG. 4, even when an exciter 20 for applying a DC magnetic flux to the molten metal 7 is attached instead of the circuit for superimposing a DC current on the exciting coil 2, the exciter 20 By supplying a DC current from the DC power supply 17 to the DC power supply 17, a DC component 19 is generated in the alternating magnetic flux 9. Therefore, even in such a configuration, the interaction force between the induced current 10 and the direct current component 19 of the alternating magnetic flux 9 works in the direction of suppressing the flow, and thus resists the compressive force 13 which is the component force in the x-axis direction. It is possible to reduce the liquid flow inside the molten metal, prevent the molten metal 7 from undulating, and stably hold the molten metal 7.

[0010]

Embodiments will be described in detail below with reference to the embodiments shown in the drawings. FIG. 1 shows a molten metal holding device according to an embodiment of the present invention. In this embodiment, a circuit for superimposing a direct current on the exciting coil 2 is additionally provided. That is, as shown in the figure, an exciting coil 2 is wound around the iron core 1, and an alternating current is supplied to the exciting coil 2 from an AC power source 3 via a transformer 14 and rectifying capacitors 8 and 22. ,
A direct current is supplied to the exciting coil 2 from a DC power supply 17 via a rectifying capacitor 15 and a rectifying reactor 16.

Therefore, an exciting current 18 having a waveform in which a direct current is superposed on an alternating current as shown in FIG. 2 flows in the exciting coil 2, and therefore the two magnetic poles 4 and 5 of the iron core 1 are made to flow. In between, as shown in FIG. 3, an alternating magnetic flux 9 on which a DC component 19 is superposed is generated in the x direction which is the horizontal direction in FIG. In FIG. 1, the rectifying capacitor 15
The reactor 16 is for preventing an alternating current component from flowing to the DC power supply 17.

Between the magnetic poles 4 and 5, the lower end of an upper and lower open container 6 which is opened at the top and bottom is located. The upper and lower open container 6 has a rectangular cross section and a rectangular tube shape, and is made of a heat-resistant insulating material such as ceramic. Inside the upper and lower open container 6, a molten metal 7 such as zinc, aluminum or other metals or alloys thereof is arranged. Therefore, as shown in FIG. 3, an alternating magnetic flux 9 on which the DC component 19 is superposed is generated in the molten metal 7 in the x direction which is the left-right direction in FIG. An induced current 10 is generated in the axial direction, and a push-up electromagnetic force 11 which is an interaction between the induced current 10 and the alternating magnetic flux 9 acts in the z-axis direction which is the upper side in FIG. .

Here, the DC current supplied from the DC power supply 17 causes a DC component 19 in the alternating magnetic flux 9 between the magnetic poles 4 and 5. The alternating current component of the alternating magnetic flux 9 is the molten metal 7
Is attenuated at the surface layer of. Therefore, the DC component 19 of the alternating magnetic flux 9 acts strongly inside the molten metal 7. Therefore, the interaction force between the induced current 10 and the direct current component 19 of the alternating magnetic flux 9 acts as a braking force in the direction of suppressing the flow, so that the liquid inside the molten metal resists the compression force 13 acting in the x-axis direction. It has the function of reducing flow. As described above, in this embodiment, since the DC current is supplied to the exciting coil 2, the DC component 19 is generated in the alternating magnetic flux 9 to prevent the molten metal 7 from waving and stably hold the molten metal 7. It becomes possible.

Specifically, the inductance of the electromagnet consisting of the iron core 1 and the exciting coil 2 is 70 μH and the resistance is 0.0.
1Ω, capacitor 15; 320μF, reactor 16;
At 5 mH, it is possible to energize AC component 500A (frequency 2kHz) and DC component 500A as exciting current,
As the x-direction magnetic flux density, an alternating magnetic flux having a direct current component of 0.3 (T) and an alternating current component of 0.3 (T) could be obtained. When wood metal was used as the molten metal by using this magnetic flux, the molten metal could be stably held.

Another embodiment of the present invention is shown in FIG. In this embodiment, a circuit (1
5, 16, 17), an exciting device 20 for applying a DC magnetic flux to the molten metal 7 is additionally provided.
That is, on both sides of the upper and lower open container 6, above the magnetic poles 4 and 5, the exciting devices 20 are arranged, and these exciting devices 20 are connected to the DC power supply 17. Therefore, a DC component 19 is generated in the alternating magnetic flux 9 by supplying a DC current from the DC power supply 17 to the exciter 20.

As described above, in this embodiment, as in the above-described embodiment, the DC component 19 is generated in the alternating magnetic flux 9, so that x
The liquid flow inside the molten metal is reduced against the compressive force 13 acting in the axial direction, the wavy state of the molten metal 7 is prevented, and the molten metal 7 can be stably held.

The molten metal holding device of the present invention can be applied as a steel plate plating device as shown in FIG.
That is, by passing the steel plate 30 passed through the drum 31 into the molten metal 7 and sealing the lower surface of the molten metal 7 in a non-contact manner, the plating apparatus can be made compact and the exchangeability of the plating solution can be improved. To be Further, by connecting this configuration in multiple stages, there is an advantage that the multi-layer plating process becomes easy.

[0018]

As described above in detail with reference to the embodiments, according to the present invention, the exciting coil is provided with a circuit for superimposing a DC current, or the DC magnetic flux is applied to the molten metal. Since a device to be operated is attached, a direct current component is generated in the alternating magnetic flux. Therefore, the interaction force between the induction current and the direct current component of the alternating magnetic flux acts in the direction of suppressing the flow of the molten metal, and the flow inside the molten metal is reduced,
The molten metal will be held stably.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a molten metal holding device according to a first embodiment of the present invention.

FIG. 2 is a graph showing an excitation coil current waveform of the molten metal holding device according to the first example of the present invention.

FIG. 3 is a graph showing a magnetic flux density waveform of the molten metal holding device according to the first example of the present invention.

FIG. 4 is a configuration diagram of a molten metal holding device according to a second embodiment of the present invention.

FIG. 5 is a configuration diagram of a molten metal holding device according to a third embodiment of the present invention.

FIG. 6 is a configuration diagram of a molten metal holding device according to a conventional technique.

[Explanation of symbols]

 1 Iron Core 2 Excitation Coil 3 AC Power Supply 4, 5 Magnetic Pole 6 Vertical Opening Container 7 Molten Metal 8 Matching Capacitor 9 Alternating Magnetic Field 10 Induced Current 11 Push Up Electromagnetic Force 13 Compressive Force 14 Transformer 15 Rectification Capacitor 16 Rectification Reactor 17 DC Power Supply 18 Exciting current 19 DC component of alternating magnetic flux 20 Exciting device 22 Rectifying capacitor 30 Steel plate 31 Drum

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kenichi Unoki Kenichi Unoki 4-6-22 Kannon Shinmachi, Nishi-ku, Hiroshima-shi, Hiroshima Mitsubishi Heavy Industries, Ltd. Hiroshima Research Institute (72) Inventor Motomi Nakajima Kannon, Nishi-ku, Hiroshima-shi, Hiroshima 4-6-22 Shinmachi Mitsubishi Heavy Industries Ltd. Hiroshima Research Institute (72) Inventor Kazumasa Mihara 4-6-22 Kannon Shinmachi Nishi-ku, Hiroshima City Hiroshima Prefecture Mitsubishi Heavy Industries Ltd. Hiroshima Works

Claims (2)

[Claims] 1. A molten metal holding device for holding an alternating magnetic flux in the horizontal direction using an exciting coil at the lower end of the molten metal to be held, and holding the molten metal in the air by an electromagnetic force, wherein the exciting coil is used. A molten metal holding device characterized in that a circuit for superimposing a DC current is attached to the molten metal holding device. 2. A molten metal holding device for holding an alternating magnetic flux in the horizontal direction using an exciting coil at the lower end of the molten metal to be held, and holding the molten metal in the air by electromagnetic force. 1. A molten metal holding device, characterized in that a device for applying a DC magnetic flux is attached to the molten metal holding device.