JPS6373868A - Electromagnetic pump - Google Patents

Abstract

PURPOSE:To prevent cooling and solidification of a molten metal by making a conduit of a conductive refractory material and providing an induction heating means of said conduit. CONSTITUTION:In a molten-metal feeder using an electromagnetic pump, a crucible B containing a molten metal A is fitted with an electromagnetic pump C and the molten metal A is caused to flow little by little. At the lower end of the crucible B, a conduit 1 communicating into the inner part thereof is installed so that its axis extends vertically, and said conduit 1 is made of a conductive and refractory material. Further, a plurality of coils 2 wound in the manner of surrounding the conduit 1 is arranged in the outer part of said conduit 1. These coils 2 have two functions of generating a shifting magnetic field to induction-heat the conduit 1 and also generating another shifting field for causing the molten metal A to flow. Thus, not only the conduit 1 can be induction-heated beforehand but also cooling and solidification of the molten metal A can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an electromagnetic pump suitable for supplying a small amount of molten metal.

[Conventional technology] Generally, electromagnetic pumps use molten metal (hereinafter referred to as molten metal).

), by supplying polyphase AC power to the coil surrounding the conduit, a moving magnetic field is generated, which sends the molten metal in the conduit from one end to the other. be.

[Problems to be Solved by the Invention] By the way, the 'Qirli pump of the above configuration has a small problem. When flowing the molten metal R, since the flow of the molten metal is slow, there was a problem that the molten metal h<> solidified at the joints while flowing through the GPff, and as a result, the conduit gradually became clogged. This tendency was particularly noticeable when the diameter of the conduit was relatively small because the heat capacity of the molten metal was small.

[Object of the Invention] This invention was made in order to solve the two-legged problem, and therefore it is an object of the present invention to provide an electromagnetic pump that can flow at least 1 mol of molten 7J4 without clogging the inside of the conduit. target

[Means for Achieving the Object] In order to achieve the objectives of the present invention, a conduit is constructed of a conductive refractory material, and a conduit is constructed of a conductive refractory material. Shin Shout (To A To Ra ni 1)
r-j, -7 kite 6 In this case, the entire conduit may be formed of a conductive refractory material11. Alternatively, the conduit may have a multi-layer structure, with only one layer, for example the innermost layer, being made of a conductive refractory material.

[Operation] When an electric current is passed through the induction heating means, since the conduit is made of a conductive refractory material, an eddy current flows inside the conduit, and this eddy current heats the conduit, and as a result, the molten metal is heated. After the temperature of the conduit has reached the required temperature, the electromagnetic coil is subjected to normal pumping action.

[Embodiments] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows a molten metal supply device using an electromagnetic pump according to the present invention. In this molten metal supply device, an electromagnetic pump C according to the present invention is attached to a bottom B containing molten metal A.
Molten metal A is allowed to flow little by little. That is, a conduit I that communicates with the inside is attached to the lower end of the Ruppo B with its axis directed upward and downward. This conduit l is made of a material that is both electrically conductive and fire resistant, and graphite is used in this embodiment. Further, the diameter of the conduit I is formed to be relatively small in order to allow a small amount of molten metal A to flow therethrough. In particular, in this case, the diameter is set to such an extent that the frictional resistance between the molten metal A and the conduit 1 and the viscosity of the molten metal A can prevent the molten metal A from freely falling from the conduit 1. ing. In addition, each conduit 1 is external to the conduit 1.
A plurality of coils 2 are arranged along the conduit 1 so as to surround the conduit 1 . These coils 2 include a large Ti source (not shown) that flows a large current such that when a moving magnetic field is generated by the coils 2, the moving magnetic field can inductively heat the conduit l, and a Melted by magnetic field? n
It is switchably connected to a small power source (not shown) that supplies a small current sufficient to flow A. As is clear from this, in this embodiment, the coil 2 not only functions as a coil for flowing the melt, but also functions as an induction heating means.

Note that it is desirable to use a single-phase AC power source as a large power source and a small power source, but if efficiency is not taken into account, a multi-purpose AC power source with three or more phases may be used. , a multi-phase AC power supply with three or more phases may be used as a small power supply. In addition, in the case of a single-phase AC power supply, so that the magnetic field moves from the upper end of the conduit l toward the lower end,
Single-phase AC is passed sequentially from the coil 2 on the second end to the coil 2 on the bottom end, and in the case of a three-phase AC power supply, three-phase AC? The terminals of the U source are connected according to the phase order of the current.

Therefore, in the molten metal supply device of Yu Kizo-sei, first, power is supplied to the coil 2 from a large power source to generate a strong eddy current in the conduit 1, thereby efficiently heating the conduit 1 by induction. At this time, regardless of whether or not there is molten metal in the conduit l, sufficient power is supplied to accurately prevent the molten metal A from solidifying as the temperature decreases when the molten metal A passes through the conduit i. After the conduit l is heated as described above, a small current necessary for the discharge of the molten metal is supplied from the small power source to the coil 2, and the molten metal A is not sent out from the conduit l.

Furthermore, the molten metal A and the conduit I
The friction and viscous resistance and the weight of molten metal A are balanced,
Is it melted because it looks like this? A There is no flow from A or conduit l.

In addition, in this example, friction, viscous resistance, and melting resistance will be discussed. n By balancing the own weight of A, the melt ? n
We are trying to prevent the free flow of A, but Go Il 2
If the three-phase wiring is used to generate a strong moving magnetic field from the lower end coil 2 to the upper end coil 2, thereby preventing the melt Δ from freely flowing out, the melt/AA The molten metal 71A in the conduit 1 can be heated even when no molten metal is flowing, and the molten metal A in the conduit 1 can be constantly prevented from cooling and solidifying.

Next, other embodiments of the invention shown in FIGS. 2 and 3 will be described.

In the case shown in Fig. 2, an electromagnetic pump C according to this invention is mounted on the lower end of the circumferential surface of a crucible B with its conduit 1 facing in the horizontal direction, and the molten liquid flowing out from the conduit 1 is carefully mounted. ?
AA flows through l) J I) to reach other locations where molten metal is required.

In addition, as shown in Fig. 3, an electromagnetic pump C is attached to the lower end of the circumferential surface of the crucible B with its conduit 1 facing diagonally upward. The liquid is poured into another container or the like via a pouring device E attached to the tip of the conduit 1.

[Effects of the Invention] As explained above, according to the electromagnetic pump of the present invention, when the conduit is formed of a conductive refractory material, an induction heating means for the conduit is provided and the conduit is inductively heated in advance. Therefore, even if the number of claws of the molten metal flowing in the conduit is reduced, the molten metal can be prevented from cooling and solidifying.

[Brief explanation of the drawing]

1 to 3 are longitudinal sectional front views showing one embodiment of the present invention, respectively. C... Electromagnetic pump, l... Conduit, 2...
····coil.

Claims (2)

[Claims] (1) An electromagnetic pump consisting of a conduit through which molten metal flows, and a plurality of coils arranged outside the conduit along the conduit, characterized in that the conduit is made of a conductive refractory material. electromagnetic pump. (2) The electromagnetic pump according to claim 1, wherein the conductive refractory material is graphite.