Metal melting furnace vortex chamber body and metal melting furnace using the same

A metal melting furnace vortex chamber body having a vortex chamber capable of communicating with a storage space of a furnace body having the storage space storing molten metal. The metal melting furnace vortex chamber body has a drop weir part which switches a communication state and an interruption state between the storage space and the vortex chamber. The drop weir part includes a blind drop weir and an opening type drop weir which are formed as separate members. At least the blind drop weir is movable up and down with respect to the vortex chamber body and is selectively positioned at an upward movement position and a downward movement position so as to switch the communication state and the interruption state.

BACKGROUND

1. Field of the Invention

The present invention relates to a metal melting furnace vortex chamber body and a metal melting furnace using the same. For example, the present invention relates to a vortex chamber body which is used in a metal melting furnace for conductors (conductive materials) such as Al, Cu, and Zn, alloy of at least two of Al, Cu, and Zn, or Mg-alloy, and a metal melting furnace using the same.

2. Description of Related Art

Hitherto, there have been known methods of generating a vortex inside a vortex chamber body by disposing an electromagnetic coil on the outer circumference of the vortex chamber body or disposing a permanent magnet type shifting magnetic field generator below the vortex chamber body. The vortex chamber body and a furnace body may be integrated with each other or may be connected to each other by flange joints.

Even in any of these methods, the vortex chamber body and the furnace body are connected to each other by a molten metal inlet and a molten metal outlet bored in a furnace wall of the furnace body. Since molten metal rapidly rotates inside the vortex chamber body and a non-melted material rapidly rotates therein, an inner wall of the vortex chamber body is intensively abraded. For this reason, when the management is not sufficiently performed, a molten metal leakage accident occurs in some cases.

This is because the vortex is generated by a molten metal outer circumferential driving method, hence the vortex chamber wall thickness may not be increased. The molten metal leakage accident directly leads to an accident in which the molten metal of the furnace body leaks. In this case, a large amount of the molten metal comes out of the furnace, so that a very dangerous severe accident occurs.

Therefore, it is considered that the vortex chamber needs to be naturally replaced when the durable years expire. Accordingly, there has been expected a rapid melting furnace vortex chamber capable of safely stopping a work even when the molten metal leakage accident occurs during the operation of the rapid melting furnace.

SUMMARY OF THE INVENTION

Technical Problem

The present invention is made to solve the above problems. It is an object of the present invention to provide a metal melting furnace vortex chamber body which is able to prevent accident, be easily maintained and be simple structure, and a metal melting furnace using the same.

Solution to Problem

The present invention provides a metal melting furnace vortex chamber body with a vortex chamber capable of communicating with a storage space of a furnace body having the storage space storing molten metal, the metal melting furnace vortex chamber body comprising:

a drop weir part which switches a communication state and an interruption state between the storage space and the vortex chamber,

wherein the drop weir part includes a blind drop weir and an opening type drop weir which are formed as separate members,

wherein at least the blind drop weir is movable up and down with respect to the vortex chamber body and is selectively positioned at an upward movement position and a downward movement position so as to switch the communication state and the interruption state, and

wherein the opening type drop weir includes notches which communicate the vortex chamber and the storage space with each other in the communication state.

The present invention provides a metal melting furnace comprising:

a furnace body which includes a storage space storing molten metal;

a vortex chamber body which includes a vortex chamber capable of communicating with the storage space of the furnace body; and

a drop weir part which changes a communication state and an interruption state between the storage space and the vortex chamber,

wherein the drop weir part includes a blind drop weir and an opening type drop weir which are formed as separate members,

wherein at least the blind drop weir is movable up and down with respect to the vortex chamber body and is selectively positioned at an upward movement position and a downward movement position so as to switch the communication state and the interruption state, and

wherein the opening type drop weir includes notches which communicate the vortex chamber and the storage space with each other in the communication state.

DETAILED DESCRIPTION OF THE INVENTION

Referring toFIGS. 1 to 7, a non-ferrous metal melting furnace of an embodiment of the present invention will be described.

The non-ferrous metal melting furnace of the embodiment of the present invention is where arbitrary metal or non-ferrous metal of a conductor (conductive material), for example, Al, Cu, and Zn, alloy of at least two of Al, Cu, and Zn, or Mg-alloy or the like is charged and heated with a burner or the like so as to be melted.

In this embodiment, as understood particularly fromFIG. 1, a furnace body1and a vortex chamber body2are formed as separate members, and these members are mechanically coupled to each other by an attachment tool5so as to communicate with each other through an opening1B bored in a side wall1A of the furnace body1.

The furnace body1has, for example, a capacity of several tons to several tens of tons and heats and melts an ingot or the like of non-ferrous metal or the like with a burner so as to make a molten metal M of the non-ferrous metal or the like. The furnace body1includes a storage space1C which stores the molten metal M.

The vortex chamber body2has, for example, a capacity capable of storing several hundreds of kilograms of the molten metal M, and is generally used to melt non-ferrous metal as a raw material which is light like aluminum chips or the like to float on the surface of the molten metal M and is not easily melted. In the vortex chamber body2, the molten metal M is rapidly rotated as a vortex while being heated with a burner or the like inside the furnace body so that the temperature of the molten metal increases, and chips or the like of the non-ferrous metal as a raw material are attracted into the vortex so as to be melted. The vortex chamber body2includes a vortex chamber2C which stores the molten metal M.

The vortex chamber body2is formed as a channel shape of which one end is formed as a released end and the other end is formed as a blocked end, and the released end communicates with the storage space1C.

The furnace body1and the vortex chamber body2communicate with each other, and the molten metal M of the non-ferrous metal circulates therebetween so that the liquid surface levels thereof match each other.

The attachment tool5may be of any type as long as the vortex chamber body2may be stably attached to the furnace body1. In the embodiment, as understood particularly fromFIGS. 7(a), 7(b), and 7(c), the attachment tool is formed as a channel shape of which one end is formed as a released end and the other end is formed as a blocked end as the vortex chamber body2. More specifically, an attachment tool4includes a so-called channel-shaped attachment tool body4A, a blocking plate4B which blocks the channel, and a flange4C which folds back the attachment tool body4A outward at the released side, and a vortex chamber body support space4D is formed by these members. Further, the attachment tool body4A is provided with an opening4E as understood particularly fromFIG. 1.

Further, the released end side becomes the flange4C which is used for the attachment to the furnace body1. That is, the attachment tool4includes the vortex chamber body support space4D which inevitably has a so-called channel shape. When the vortex chamber body2is stored in the vortex chamber body support space4D of the attachment tool4and the flange4A is fastened to the furnace body1with bolts5,5. . . in this state, the vortex chamber body2is fixed to the furnace body1. In this state, as described above, the vortex chamber2C of the vortex chamber body2communicates with the storage space1C of the furnace body1through the opening1B as understood particularly fromFIG. 1.

In addition, the vortex chamber body2includes a drain tap2D which is used to drain the molten metal M in a case of, for example, emergency as understood particularly fromFIG. 1. The opening4E which communicates with the drain tap2D is bored in the attachment tool4.

Further, the vortex chamber body2is provided with a drop weir part6. The drop weir part6includes a blind drop weir7and an opening type drop weir8as two weir plates, and these drop weirs are inserted into a vertical groove2B formed inside a side wall2A of the vortex chamber body2so as to be individually movable up and down. That is, the blind drop weir7is disposed at the side of the furnace body1, and the opening type drop weir8is disposed at the opposite side to the furnace body1.

These weirs7and8are assembled so that they may not only move up and down but also be completely taken out of the vortex chamber body2. In this way, the weirs7and8may be separated from the vortex chamber body2, so that the maintenance of the furnace body1and the vortex chamber body2may be performed in an extremely easy way. That is, it is hard to avoid a state where so-called sludges such as oxides are inevitably accumulated with the operation in the furnace body1and the vortex chamber body2. However, since both the weirs7and8may be separated, there is an advantage that the weirs may be easily cleaned.

The blind drop weir7and the opening type drop weir8are respectively illustrated inFIGS. 5 and 6.

As shown inFIG. 5, the blind drop weir7is formed as a single plate shape, and a handle7A is attached to the top portion thereof. As shown inFIG. 6, the opening type drop weir8includes an inlet opening8B and an outlet opening8C as notches formed at the left and right sides of the lower portion of one plate. That is, the outlet opening8C and the inlet opening8B are formed with a predetermined distance therebetween at the lower end side of a plate-like weir body8aof the opening type drop weir8. A handle8A is provided.

As understood particularly fromFIG. 3, the blind drop weir7and the opening type drop weir8are adapted to independently slide up and down and to stably take a downward movement position and an upward movement position. For example, the vortex chamber body2and the furnace body1are interrupted from each other in the state ofFIG. 3, and the vortex chamber body2and the furnace body1communicate with each other through the inlet opening8B and the outlet opening8C in the state ofFIG. 4.

As a mechanism of driving the two drop weirs, that is, the blind drop weir7and the opening type drop weir8, in the up and down direction, various types such as a chain type, a screw type, a manual type and an electric type may be supposed. However, since the weirs7and8are extremely light in weight, a driving mechanism of any type is very simple. Here, a specific description thereof will be omitted. Further, the blind drop weir7and the opening type drop weir8may be formed of any material such as a fire-resisting material which has corrosion resistance with respect to the non-ferrous metal or the like and has a high thermal conductivity. A cheap fire-resisting material which is sold in the market is enough.

As understood particularly fromFIG. 2, a permanent magnet type shifting magnetic field generator10is provided at the lower position outside the vortex chamber body2. The shifting magnetic field generator10may be of an electromagnetic type. For example, the shifting magnetic field generator10shown inFIGS. 8(a) and 8(b)may be used. InFIGS. 8(a) and 8(b), a configuration may be employed in which a rotation magnet body52is provided inside a non-magnetic casing51. In the rotation magnet body52, a motor53is provided inside the casing54, a shaft53aof the motor53is supported by a bearing54a, and a disk-like magnet base55is rotatable by the motor53. A plurality of permanent magnets56,56. . . are fixed onto the magnet base55at the interval of 90°. The upper and lower surfaces of the permanent magnets56,56. . . are formed as magnetic poles. Furthermore, as understood fromFIG. 8B, the adjacent permanent magnets56,56. . . are magnetized so as to have different polarities. The permanent magnets56,56. . . are covered by a non-magnetic cover57.

With the above-described configuration, as shown inFIG. 3, a magnetic flux (magnetic lines of force) MF from the permanent magnets56,56. . . penetrates the molten metal M inside the vortex chamber6, or the magnetic flux MF penetrating the molten metal M enters the permanent magnets56,56. . . . Since the permanent magnets56,56. . . rotate in this state, the magnetic flux MF also moves inside the molten metal M, so that the molten metal M also rotates by the electromagnetic force.

By the rotational driving of the shifting magnetic field generator10, the molten metal M inside the vortex chamber body2whirls by an eddy current and starts to rotate at a high speed, for example, 200 to 300 rpm. The molten metal M which rotates at a high speed is pressed in the outer circumferential direction inside the vortex chamber body2by the centrifugal force thereof. The force is strong at the lower side of the vortex chamber body2. As a result, the molten metal is discharged from the outlet opening8C of the opening type drop weir8, and enters the furnace body1. Further, the molten metal M inside the furnace body1returns from the inlet opening8B to the vortex chamber body2. When non-ferrous metal chips or the like are input into the vortex of the vortex chamber body2, the chips or the like are attracted into the vortex, and hence may be rapidly melted.

In addition, the furnace body1includes, for example, a shifting magnetic field generator different from that of the vortex chamber body2, and hence rotates the molten metal M at, for example, 20 to 30 rpm. Further, the molten metal M as a product may be derived from the furnace body1to the outside.

Next, a running operation of the above-described metal melting furnace will be described.

Before starting the operation of melting the molten metal M by the vortex chamber body2, the molten metal M inside the furnace body1and the molten metal M inside the vortex chamber body2have the same liquid surface level. By the shifting magnetic field generator10, the molten metal M inside the vortex chamber body2is rotated right as illustrated inFIG. 1.

In this state, chips or the like of non-ferrous metal as a raw material are input to the vortex chamber body2. The chips or the like are further rotated while being attracted into the vortex of the molten metal M inside the rapidly rotating vortex chamber body2so as to be efficiently melted. The molten metal M which rotates inside the vortex chamber body2flows from the outlet opening8C into the furnace body1.

Accordingly, the liquid surface level of the molten metal M of the furnace body1becomes higher than the liquid surface level of the molten metal M inside the vortex chamber body2. Thus, the molten metal M inside the furnace body1flows into the vortex chamber body2through the inlet opening8B so that the liquid surface levels become equal to each other. That is, a difference in level, that is, a head is normally generated between the level of the molten metal M of the furnace body1and the level of the molten metal M of the vortex chamber body2, so that the molten metal M circulates.

In this way, in the embodiment of the present invention, the molten metal M inside the vortex chamber body2is rotationally driven by the shifting magnetic field generator10, so that chips or the like as an input raw material may be efficiently melted while being attracted into the vortex.

Incidentally, the embodiment of the present invention also has a feature in handling emergency case. That is, in general, the molten metal M rapidly rotates inside the vortex chamber body2, and further a non-melted material as a raw material also rotates rapidly in this way. For this reason, it is hard to avoid a state where a non-melted raw material collides with the inner wall of the vortex chamber body2. As a result, the inner wall of the vortex chamber body2is noticeably abraded, and hence the wall is thinned eventually. In addition, a stress such as expansion and contraction by heat is repeatedly applied to the inner wall of the vortex chamber body2. Thus, the thinned inner wall of the vortex chamber body2is cracked by the stress, and hence the molten metal M inside the vortex chamber body2may leak to the outside. In this case, the molten metal M of the furnace body1is also leaks, and this case may cause a severe accident.

Incidentally, such an accident may be prevented according to the device of the embodiment of the present invention. That is, in a case where the vortex chamber body2is damaged, the blind drop weir7is promptly moved down so as to interrupt the communication between the vortex chamber body2and the furnace body1, and hence an outlet22for the large amount of the molten metal M inside the furnace body1may be blocked.

Furthermore, after the communication is interrupted by the blind drop weir7, the molten metal M which remains inside the vortex chamber body2may be promptly drained to the outside by the drain tap2D and the opening4E of the attachment tool4. Accordingly, it is possible to prevent a case where the molten metal M remains inside the vortex chamber body2and is cooled and solidified inside the vortex chamber body2. When the molten metal M is solidified inside the vortex chamber body2, a severe damage is caused in that the vortex chamber body2and the furnace body1may not be used again, but this problem may be prevented by the embodiment.

Furthermore, the shape of the vortex chamber body2is formed as a rectangular shape (box shape) when viewed from the upside in the embodiment, but it is needless to mention that the shape may be a circular shape, a semi-circular shape, or an oval shape.

Further, it is needless to mention that the present invention may be applied to not only the above-described non-ferrous metal melting furnace, but also other metal melting furnaces.