JPH07204829A - Core-less type device for supplying/discharging molten metal - Google Patents

Abstract

PURPOSE:To provide a core-less type molten metal supplying/discharging device, in which the constitution is simple and particularly, the supplying/discharging efficiency of molten nonferrous alloy can be improved and a problem of the oxidation of the molten non-ferrous alloy can be avoided and further, the constant quantity can be drawn up and the safe operation is executed. CONSTITUTION:This device is composed of a horizontally long molten metal feeding pipe body 1, a first to a third induction coils 2-4 wound in the same winding direction on the outer peripheral part of the molten metal feeding pipe body 1 and arranged in order along the length direction of this pipe body 1, secondary coils 5-7 for supplying the electric currents having the same phase order as the order of the induction coils 2-4, respectively and a power transformer 11 containing primary coils 8-10 for supplying each of the secondary coils 5-7 and applying a delta-connection.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to supplying a coreless molten metal for supplying and discharging a non-ferrous alloy such as a molten aluminum alloy or magnesium alloy from a furnace toward a mold part or a mold part. The present invention relates to a hot water discharge device.

[0002]

2. Description of the Related Art Conventionally, as means for supplying and discharging hot water of this type,
Generally, after the molten metal in the melting furnace is manually or remotely pumped up using a ladle with a handle, the ladle is poured into a predetermined sleeve or pouring port, Therefore, at the time of pumping or pouring, so-called entrainment phenomenon of air or gas occurs in the molten metal, and the molten metal is highly oxidized, and the pouring method is suitable especially for magnesium alloys that are difficult to oxidize. On the other hand, there is a problem that there is a large variation in the pouring amount at each pouring time, and when the pumping is done by hand, for example, the molten metal scatters and there is a problem in work safety. There's a problem.

In order to solve such a problem, for example, a core is inserted into a duct having a circular tubular shape, and a stator is provided on an outer peripheral portion of the duct so that a moving magnetic field is generated in the stator in the longitudinal direction of the duct. There is known an apparatus configured to pump molten metal poured between a duct and a core based on the operation principle of a three-phase induction motor or a so-called linear motor by sequentially arranging coils.

[0004]

However, in the structure of the above-mentioned prior art, it is necessary to form the core for the passage of the magnetic flux and the stator of the coil for forming the moving magnetic field by the iron material which is a ferromagnetic material. Therefore, the molten metal has a considerable weight and is expensive, and since the molten metal passes through a narrow gap formed between the duct and the core, there is a problem that the efficiency of supplying and discharging hot water is poor and the external shape becomes large.

[0005] In Japanese Utility Model Laid-Open No. 52-36717, a three-phase induction coil is connected in a molten metal passage portion that connects the furnace body and the tap hole in a siphon manner so that the two phases are opposite phases. It is disclosed that there is a structure in which the molten metal is discharged from the molten metal outlet by applying an electromagnetic force due to a steep inrush current when closing the molten metal to the molten metal in the molten metal passage portion. Since the siphon principle is applied and the inrush current is used, it is not possible to control the amount of hot water discharged in a stable manner.

The present invention has been made to solve the above-mentioned problems of the prior art, has a simple structure, and in particular, can improve the supply and discharge efficiency of molten non-ferrous alloys such as aluminum alloys and magnesium alloys. It is an object of the present invention to provide a molten metal supply / discharge apparatus capable of avoiding the problem of oxidation of a non-ferrous alloy molten metal, further capable of pumping in a fixed amount, and capable of performing a safe operation.

[0007]

In order to solve the above-mentioned problems of the prior art, the main constitution of the present invention is a horizontally long hot water pipe and an outer peripheral portion of the hot water pipe in the same winding direction. First to third induction coils that are mounted and are sequentially arranged along the length direction of the hot water pipe body, and three-phase currents of the same phase order as the arrangement order in each induction coil. And a power transformer that supplies an induction current to each of the secondary coils and that includes a primary coil that is delta-connected, and a three-phase alternating current with a variable output frequency to the primary coil of the power transformer. A power supply unit for supplying the molten metal is provided, and one end side in the length direction of the hot water feeding pipe body is made to face the supply part of the molten metal, and the other end side in the length direction is made to face the hot water supply and discharge part of the molten metal. It is characterized by

[0008]

When a three-phase alternating current is supplied to the primary coil of the power transformer from the power supply section, a large current flows in the secondary coil of the power transformer, and thus a large current also flows in the first to third induction coils, An eddy current based on the large current is generated in the molten metal in the molten metal body by the induction coil, so that the molten metal receives a force that moves in the longitudinal direction of the molten metal body according to Fleming's left-hand rule. In this case, the first to third induction coils are arranged along the length direction of the hot water pipe body, and the arrangement order corresponds to the order of the phase shift of the supplied three-phase alternating current.
The molten metal always receives a constant force in the length direction and moves. Further, since the power supply section is capable of varying the output frequency of the supplied three-phase alternating current, the moving speed is arbitrarily adjusted,
In other words, the molten metal discharge rate can be set to a desired value.

[0009]

FIG. 1 shows a schematic configuration of one embodiment of the present invention. A molten metal supply / discharge apparatus for molten metal according to this embodiment is
The horizontally long hot water pipe 1 and the outer peripheral portion of the hot water pipe 1 are mounted in the same winding direction and are arranged in sequence along the lengthwise direction of the hot water pipe 1. 1 to 3 induction coils 2 to
4 and secondary coils 5 to 7, which supply currents to the induction coils 2 to 4 in the same phase order (U, V, W order) as the order of the arrangement, and the respective secondary coils 5 to 5. 7 and a power transformer 11 including primary coils 8 to 10 connected in a delta connection.

A power supply section (not shown) connected to the primary coils 8 to 10 of the power transformer 11 inputs a three-phase alternating current of a commercial frequency and outputs a variable three-phase output section and a predetermined frequency. It comprises an inverter having a single-phase output.

2 to 4 show a more detailed configuration diagram of the present embodiment, in which the whole of the main components are the casing 12.
The hot water feeding pipe 1 is provided so as to penetrate through the first to third induction coils 2 to 4, respectively, and both ends in the length direction thereof are fixed to the upper part of the casing 12, respectively. It is supported by a supporting member 12A that is mounted, is fixed by pressing flanges 13 and 14 attached to the outside, and is detachable via bolts 13a and 14a, respectively. The housing 12 is formed of a non-magnetic heat resistant plate having a predetermined thickness.

The hot water feeding pipe 1 includes the induction coils 2 to 4
A protective pipe 15 is fitted in a portion corresponding to the portion covered with the heat insulating material 1 on the outer peripheral portion of the protective pipe 15.
6 is installed. The molten metal is made of a non-metallic material when the molten metal is an aluminum alloy, and is made of a metallic material when the molten metal is a magnesium or zinc alloy. When it is an alloy, the protection pipe 15 and the hot water pipe body 1
The heating assisting sheet 17 is interposed between and.

More specifically, the portion where the pressing flange 13 (the same applies to the other pressing flange 14) supports both ends of the hot water feeding pipe body 1 will be described. The heat insulating material 1 is inserted into the mounting collar 18 and between the mounting collar 18 and the pressing flange 13.
9 are intervening.

Both ends of the hot water feeding pipe body 1 are respectively provided with a casing 12.
A heat insulating spacer 20 is interposed so that a portion protruding to the outside of the housing and the inside of the housing 12 are thermally separated. On the other hand, the induction coils 2 to 4 and the secondary coils 5 to 7 are formed of copper pipes capable of passing cold water, and both ends thereof are cooling water inlets 21, 23, 25 and cooling water outlets 22, 24, respectively. 26
Is projected from the housing 12.

Further, in the power transformer 11, a yoke 11A is fixed in the housing 12, and the yoke 11A is fixed.
The primary coils 8 to 10 and the secondary coils 5 to 7 are wound around A. A terminal plate 27 for a three-phase input terminal of the primary coils 8 to 10 connected in a delta connection is provided outside the housing 12.
And the induction coil 2 is provided inside the housing 12.
Two cooling fans 28 and 29 are arranged so as to face the cooling fan 4.

FIG. 5 and FIG. 6 show a concrete example of mounting the hot water supply / exhaust device constructed as described above. One end of the hot water feeding pipe 1 in the length direction is the hot water feeding unit of the relay section. It faces the inside of the hot water feeding pipe part 31 which is the supply part of the molten metal via the material 30, and the other end side in the length direction faces the fixed surface furnace 32 which is the supply and discharge part of the molten metal. There is. As can be understood from FIG. 5, the length of the hot water feeding pipe body 1 is inclined with respect to the horizontal direction, and the angle θ of the inclination is about 5 degrees in the present embodiment. The side is set higher than the other side.

A housing 12 is provided at one end of the hot water pipe 1.
The portion protruding from is covered with a protective pipe 33, the outer peripheral portion of the protective pipe 33 is covered with a heating coil 35 via a heating auxiliary sheet 34, and the outer peripheral portion of the heating coil 35 is covered with a heat insulating material 36. Is covered. On the other hand, a portion of the other end of the hot water feeding pipe 1 protruding from the housing 12 is covered with a heat insulating material 37. The heating coil 35 is supplied with a single-phase output of an inverter (not shown) that constitutes the power supply unit.

Here, as an example of electrical specifications of the power source section, a three-phase alternating current at a commercial frequency is 200 [V] 75
[A], that is, using a capacity of 15 [kVA],
In the inverter, the three-phase output unit has an output of 15 [kW] and the variable range of the output frequency is 0 to 360 [Hz], and the single-phase output unit has an output of 5 [kW] and an output frequency of 30 [kHz].
Is used. In the power transformer 11, the rated input voltage of the primary coil is 200 [V] and the rated output voltage of the secondary coil is 50 [V].
A device having a capacity of [kVA] is used.

The material of the hot water pipe 1 is appropriately selected depending on the type of non-ferrous alloy. For example, when the non-ferrous alloy is an aluminum alloy, a ceramic material is used, and when the non-ferrous alloy other than the aluminum alloy is used, a stainless material is used.

Next, regarding the operation of the present embodiment configured as described above, referring to FIG. 1 and the graphs of Table 1 and FIG. 7 as an example of pumping a non-ferrous alloy molten aluminum alloy. While explaining.

First, as shown in FIG. 1, when three-phase alternating current is supplied from the power source section to the primary coils 8 to 9 of the power transformer 11, the secondary coils 5 to 7 of the power transformer 11 are supplied with a low voltage large current. Flow and therefore the first to third induction coils 2
A large current also flows through to 4 in the order of their arrangement. When a large current flows through the induction coil, an eddy current Ie based on the large current flows in the molten metal P in the hot water feeding pipe body 1 along the inner circumferential direction of the hot water feeding pipe body 1 and on the inner surface thereof. It occurs so that it becomes larger as it gets closer. Therefore, due to the eddy current Ie and the magnetic flux generated by the induction coils 2 to 4, the molten metal P is subjected to a force having a moving direction Q along the length direction of the molten metal feeding tube according to Fleming's left-hand rule. .

In this case, the first to third induction coils 2 to 4
Are arranged along the length direction of the hot water feed pipe 1, and the order of arrangement corresponds to the order of the phase shift of the supplied three-phase alternating current, so that the molten metal P has a constant force in the length direction at all times. It will be moved in response to this. Further, since the power supply unit can change the output frequency of the three-phase output of the inverter continuously, the moving speed of the molten metal P can be adjusted arbitrarily and accurately.

In FIG. 7, the amount of molten metal discharged from the hot water feeding pipe body 1 (unit: [g]) is set as a parameter (0.2 [second], 0.5 [second] for the energization time (operating time) to the power transformer 11. Seconds],
0.8 [sec]) is shown to show how it fluctuates in each trial (10 times in total).

Table 1 shows the variation range (accuracy) of the discharged hot water amount more clearly based on FIG. According to this, any operation time is extremely short, and the accuracy obtained from the maximum value and the minimum value of the amount of hot water discharged may have a substantially constant value within a range that practically causes no problem at any operation time. It can be understood.

[0025]

[Table 1]

Since one end of the hot water feed pipe body 1 directly faces the molten metal supply portion and the other end directly faces the hot water supply / discharge water portion, at least when the hot water is fed, the molten metal and the outside air are directly exposed. There is no room for contact with. That is, oxidation of the molten metal during pumping can be completely avoided.

Further, since the hot water feeding pipe body 1 is attached to the pressing flanges 13 and 14 in a simple fitting state, it can be easily replaced according to the specifications and the like, and the inside thereof is in a hollow state. In addition, since it has an inclination in the length direction, the passage time of the molten metal can be shortened.
It can be done in [seconds]), and the state of remaining hot water after use can be completely avoided.

Since the secondary coil of the power transformer 11 is in a positional relationship capable of performing induction heating with respect to the hot water feeding pipe body 1, it has the effect of keeping the hot water feeding pipe body 1 warm.

[0029]

According to the first aspect of the present invention, the horizontally long hot water pipe and the outer peripheral portion of the hot water pipe are respectively wound in the same winding direction, and the hot water pipe is First to third induction coils sequentially arranged along the length direction, a secondary coil for supplying each induction coil with a three-phase current in the same phase order as the arrangement order, and each secondary coil The hot water supply pipe is provided with a power transformer that supplies an induction current to the coil and includes a delta-connected primary coil, and a power supply unit that supplies a three-phase alternating current with an output frequency variable to the primary coil of the power transformer. It is characterized in that one end side in the length direction of the body is made to face the molten metal supply portion and the other end side in the length direction is made to face the molten metal supply and discharge portion. The restriction factors of miniaturization such as stator and core are eliminated, and at least mechanical and structural While it is easy to form, the efficiency of supplying and discharging molten metal can be improved, and the state of direct contact with the outside air can be avoided, so safe operation can be performed and the problem of oxidation of non-ferrous alloy molten metal can be avoided. Can use a simple-shaped hot water supply pipe and a power source whose output frequency can be controlled to pump up a fixed amount of hot water.

According to the invention of claim 2, the position of the one end side of the hot water feeding pipe body is higher than the position of the other end side thereof, and the length direction thereof is approximately 5 with respect to the horizontal direction. Since it is characterized by having an inclination angle of 10 degrees, it is possible to remarkably improve the efficiency of supply and discharge of molten metal, and particularly to solve the problem of residual hot water.

According to the third aspect of the present invention, since the hot water pipe body is made of a non-metallic material, it is useful when applied to the pumping of a high melting point non-ferrous alloy molten metal such as an aluminum alloy. .

According to the invention of claim 4, since the hot water pipe body is made of a metal material, it is useful when applied to hot and cold hot water of low melting point non-ferrous alloys excluding aluminum alloys.

According to a fifth aspect of the present invention, the hot water feeding pipe body is detachably fitted and inserted so as to penetrate the first to third induction coils. Depending on the situation, it becomes easy to replace the hot water pipe.

According to the invention of claim 6, the induction coil and the secondary coil are each formed of a copper pipe having a pipe line for supplying cold water. The situation of can be avoided.

According to the invention of claim 7, the hot water pipe body,
The first to third induction coils, the secondary coil, and the primary coil are arranged in the same housing, and the housing is provided with an air cooling means for exhausting heat inside the housing. Therefore, in combination with the effect of claim 6, an unexpected situation due to an overheated state in the housing can be avoided in advance.

According to the invention of claim 8, the power source section is
Since a three-phase AC of commercial frequency is input, and a control device capable of outputting three-phase AC of continuously variable output frequency via an inverter is attached,
The amount of hot water supplied and discharged can be controlled easily and accurately.

According to the invention of claim 9, since the molten metal is a non-ferrous alloy molten metal, it is very suitable for application of the apparatus according to the present invention.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing a main part of a hot water supply / exhaust device according to the present invention.

FIG. 2 is a partially cutaway plan view showing a main part of an apparatus according to the present invention.

FIG. 3 is a side view seen from the XX direction in FIG.

FIG. 4 is a front view seen from the YY direction in FIG.

FIG. 5 is a front view showing an example of a mounted state of the hot and cold water supply device according to the present invention.

FIG. 6 is a partially cutaway plan view seen from the ZZ direction in FIG.

FIG. 7 is a graph showing an example of experimental data of one operation example of the apparatus according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hot water supply pipe body, 2-4 4th 1st-3rd induction coil, 5-7 Secondary coil, 8-10 Primary coil, 11 Power transformer, P Molten metal.

Claims (9)

[Claims] 1. A horizontally long hot water pipe and an outer peripheral portion of the hot water pipe are mounted in the same winding direction and are sequentially arranged along the length direction of the hot water pipe. First to third induction coils, a secondary coil for supplying each induction coil with a three-phase current in the same phase order as the arrangement sequence, and an induction current for each secondary coil, and A power transformer including a delta-connected primary coil, and a power supply unit that supplies a three-phase alternating current with a variable output frequency to the primary coil of the power transformer. A coreless molten metal supply / discharge apparatus, characterized in that it faces a molten metal supply part and the other end side in the length direction faces a molten metal supply / discharge part. 2. The hot water pipe has a position on the one end side higher than a position on the other end side, and a length direction thereof has an inclination angle of about 5 degrees with respect to the horizontal direction. The coreless molten metal supply / discharge device according to claim 1. 3. The coreless molten metal supply / discharge device according to claim 1, wherein the hot water feeding pipe body is made of a non-metallic material. 4. The coreless molten metal supply / exhaust device according to claim 1, wherein the hot water feeding pipe body is made of a metal material. 5. The hot water feeding pipe body is detachably fitted and inserted so as to penetrate the first to third induction coils. 1
Item 2. A coreless molten metal supply and discharge device for molten metal. 6. The induction coil and the secondary coil are each formed of a copper pipe having a pipe line for supplying cold water. The coreless molten metal supply / exhaust device according to 1. 7. The hot water feeding pipe body, the first to third induction coils, the secondary coil, and the primary coil are arranged in the same housing, and the housing is provided with the inside of the housing. An air-cooling means for exhausting heat is additionally provided.
7. The coreless molten metal supply / discharge apparatus according to any one of claims 1 to 6. 8. The power supply unit is provided with a control device capable of inputting a three-phase alternating current having a commercial frequency and outputting a three-phase alternating current having a continuously variable output frequency via an inverter. The coreless molten metal supply / exhaust device according to any one of claims 1 to 7. 9. The molten metal according to claim 1, wherein the molten metal is a non-ferrous alloy molten metal.
Item 2. A coreless molten metal supply and discharge device for molten metal.