JP7172263B2 - Melting equipment - Google Patents

Description

TECHNICAL FIELD The present invention relates to a melting apparatus, and more particularly to a melting apparatus provided with a heating coil portion into which raw material to be melted is inserted.

Conventionally, there has been known a melting apparatus provided with a heating coil portion into which raw material to be melted is inserted (see, for example, Patent Document 1).

The aforementioned Patent Document 1 discloses a melting apparatus comprising a melting furnace into which an aluminum ingot is inserted and melted. Specifically, the melting furnace includes a cylindrical furnace body made of a refractory material and a cold material charging guide disposed above the furnace body. An induction coil for heating and melting an aluminum ingot inserted into the furnace body is provided on the outer peripheral side of the furnace body. Also, the cold material charging guide is provided to guide the aluminum ingot into the melting furnace (furnace body). In addition, an outflow port is provided at the bottom of the cylindrical melting furnace through which the melted aluminum flows out.

In addition, in the above-described melting apparatus, when the ingot inside the furnace body is melted, the upper end of the ingot reaches the central position in the central axis direction of the induction coil provided in the melting furnace. It is configured such that an aluminum ingot to be melted after the ingot being melted (hereinafter referred to as an ingot to be melted next time) is inserted into the furnace body through a cold material charging guide. That is, the next ingot to be melted is inserted after the currently melted ingot is melted and reduced to a predetermined size. As a result, the aluminum ingot to be melted next time is inserted into the furnace through the cold material feeding guide and immediately inserted to the position where the melting efficiency is highest (center position in the direction of the center axis of the induction coil). , is not placed (held) in the cold material input guide in a cold state. As a result, even if the melted ingot does not flow out from the outlet because the outlet is clogged and the melted ingot scatters in the furnace, the ingot to be melted next time is not cold (because it is heated), so it can be melted next time. Even if the scattered ingot adheres to the ingot, the adhered ingot is immediately melted.

Japanese Patent No. 2819711

However, in the melting apparatus described in Patent Document 1, the ingot to be melted next time is loaded after the currently melted ingot is melted and reduced to a predetermined size, so the ingot to be melted next time is loaded. Inconveniently, the load of the induction heating by the induction coil (the size of the ingot to be heated) suddenly increases at the instant of time. Therefore, there is a problem that the control of the induction heating by the induction coil becomes unstable, making it difficult to continuously and stably melt the ingots.

The present invention has been made to solve the above-described problems, and one object of the present invention is to provide a method for dissolving a currently dissolved raw material and a molten raw material to be dissolved after the currently melted raw material. To provide a dissolving apparatus capable of stably and continuously dissolving .

In order to achieve the above object, a melting apparatus according to one aspect of the present invention includes a heating coil section into which a first raw material to be melted is inserted, a through hole through which the first melted raw material flows and falls, A support part that supports the lower end of the first molten raw material from below at a position above the lower end of the heating coil, and a second molten raw material that is melted after the first molten raw material is melted are in contact with the first molten raw material. a guide part for guiding the second molten raw material to be inserted into the heating coil part in a state in which the second molten raw material is stacked in the above-described manner, and the support part extends the length of the heating coil part in the vertical direction from the lower end of the heating coil part. It includes a raw material support surface portion that supports the lower end of the first molten raw material at an upper position by 18% or more of the height, and the lower end of the through hole is arranged below the lower end of the heating coil portion .

In the melting apparatus according to one aspect of the present invention, as described above, the support section supports the lower end of the first molten raw material from below at a position above the lower end of the heating coil section. As a result, the lower end of the first molten raw material is positioned above the lower end of the heating coil portion, so that the magnetic flux from the heating coil portion sufficiently reaches the lower end of the first molten raw material and portions in the vicinity of the lower end. . As a result, the lower end of the first molten raw material and the portion in the vicinity of the lower end can be rapidly melted, so that clogging of the through-holes by the unmelted residue at the lower end of the first molten raw material can be suppressed. As a result, the first molten raw material can be smoothly discharged from the through hole, and the scattering of the first molten raw material can be suppressed. As a result, it is possible to prevent the scattered first molten raw material from adhering to the second molten raw material. Here, when the second molten raw material is inserted into the heating coil in a state where the second molten raw material is stacked so as to be in contact with the first molten raw material, the magnetic flux from the heating coil does not reach the second molten raw material, The second melted raw material may be in a cold state. However, even in this case, since scattering of the first molten raw material is suppressed, adhesion of the scattered first molten raw material to the second molten raw material is suppressed. 1 can be suppressed from being hindered by the melted raw material. Thus, in order to bring the second molten raw material into a heated state when the second molten raw material is inserted, the second molten raw material is inserted after the first molten raw material melts and becomes smaller to a predetermined size. You don't have to control the timing like this. That is, even when the second molten raw material is stacked on the first molten raw material using the guide portion and inserted into the heating coil portion before the first molten raw material is melted and reduced to a predetermined size, the second molten raw material can be smoothly inserted into the heating coil. As a result, the size of the object to be heated by the heating coil can be made substantially constant. Thereby, the load applied to the heating coil portion can be made substantially constant. As a result, the first molten raw material and the second molten raw material can be stably and continuously melted.

The melting apparatus according to the above aspect preferably further comprises a melting furnace around which the heating coil portion is wound, into which the first raw material to be melted is inserted, and to which the guide portion is attached, wherein the melting furnace and the support portion are separated from each other. is provided. With this configuration, each of the melting furnace and the support can be replaced individually, thereby facilitating the replacement work of each of the melting furnace and the support. In addition, since the size (height) of the support portion can be changed by exchanging the support portion, the melting characteristics (dissolution rate, etc.) of the first melting raw material can be easily adjusted.

In this case, preferably, the supporting portion is provided so as to be surrounded by the inner peripheral surface of the melting furnace. With this configuration, the movement of the supporting portion is restricted by the inner peripheral surface of the melting furnace, so that it is possible to suppress the position of the supporting portion from being displaced.

In the dissolving device according to the above aspect, each of the support portion and the guide portion is preferably made of a non-magnetic material. With this configuration, the magnetic flux from the heating coil can be suppressed from being affected by the support and the guide, so that the first melting raw material can be stably melted by the heating coil. .

The melting apparatus according to the above aspect preferably further includes a high-frequency power source that supplies power to the heating coil, and a control device that controls the operation of the high-frequency power source. In a state where the power is set substantially constant, the melting time of the first melting raw material by the heating coil unit is determined based on the preset relationship between the amount of the first melting raw material to be melted and the amount of power supplied from the high-frequency power source. and the controller is configured to control the high-frequency power source to melt the raw material for the determined first melting time . With this configuration, the required amount of the first melting raw material can be dissolved without detecting the amount of melting by a weight sensor or the like. As a result, the number of parts for melting the first melting raw material can be reduced. Moreover, the control for melting the first raw material can be simplified compared to the case where the power of the high-frequency power source is controlled (feedback control) based on the melting amount.

In addition, since the amount of power supplied from the high-frequency power source is substantially constant, the control load for determining the melting time of the first melting raw material can be reduced compared to the case where the amount of power supplied fluctuates. Moreover, the dissolution time can be calculated more accurately and quickly than when the user manually calculates (determines) the dissolution time.

In the melting apparatus according to the above aspect, the raw material support surface portion is preferably configured to support the central portion of the lower end of the first raw material to be melted in plan view. Here, when the first molten raw material is heated by the magnetic flux of the heating coil, the surface of the first molten raw material is mainly heated by the skin effect. As a result, melting starts from the outer surface of the first raw material to be melted, and the central portion of the raw material to be melted is melted at a relatively late stage. That is, the melting progresses gradually from the outer surface of the first raw material toward the center. Furthermore, since the magnetic flux concentrates on the lower end (corner) of the first raw material to be melted, the rate of progress of melting on the lower end side is rapid. As a result, the first molten raw material has a shape that tapers downward. Therefore, by configuring the raw material support surface portion to support the central portion of the lower end of the first molten raw material, the tapered tip (lower end) side of the first molten raw material can be supported in a stable state.

In this case, preferably, a plurality of through-holes are provided, and the raw material support surface portion is formed by a portion between the plurality of through-holes in the support portion. According to this structure, a plurality of through holes are provided so as to be adjacent to the raw material supporting surface portion. Since the first molten raw material melted from the first molten raw material flows toward the tip end side of the tapered first molten raw material (the portion in contact with the raw material supporting surface portion), the first molten raw material thus melted flows. , the raw material can be dropped more smoothly from the plurality of through-holes adjacent to the raw material supporting surface portion.

According to the present invention, as described above, the raw material that is currently being dissolved and the raw material that is to be dissolved after the raw material that is currently being dissolved can be stably and continuously melted.

1 is a schematic diagram showing the overall configuration of a melting device according to a first embodiment; FIG. FIG. 4 is a perspective view of a support of the dissolving device according to the first and second embodiments; FIG. 4 is a top view of the support of the dissolving device according to the first and second embodiments; FIG. 4 is a side view of the support of the dissolving device according to the first and second embodiments; FIG. 4 is a diagram showing the distribution of magnetic flux density in the vicinity of the heating coil obtained by simulation (the lower end of the heating coil and the lower end of the raw material to be melted are substantially flush with each other). FIG. 4 is a diagram showing the distribution of magnetic flux density in the vicinity of the heating coil obtained by simulation (the lower end of the raw material to be melted is located above the lower end of the heating coil). FIG. 5 is a diagram showing the distribution of Joule heat density near the heating coil section obtained by simulation. FIG. 4 is a diagram for explaining a state in which the raw material is dissolved; FIG. 4 is a diagram for explaining the relationship between time and electric power when a plurality of raw materials to be melted are continuously melted; FIG. 5 is a schematic diagram showing the overall configuration of a dissolving device according to a second embodiment; FIG. 4 is a schematic diagram showing the overall configuration of a dissolving device according to a first modified example of the first and second embodiments; FIG. 11 is a perspective view of a support portion of a dissolving device according to a first modification of the first and second embodiments; FIG. 11 is a perspective view of a support portion of a dissolving device according to a second modification of the first and second embodiments;

Embodiments embodying the present invention will be described below with reference to the drawings.

[First embodiment]
The configuration of the dissolving device 100 according to the first embodiment will be described with reference to FIGS. 1 to 9. FIG.

(Configuration of dissolving device)
As shown in FIG. 1, the melting apparatus 100 includes a high frequency power board 1. As shown in FIG. The high-frequency power panel 1 is configured to supply high-frequency (for example, 10 kHz) AC power to a heating coil section 11, which will be described later. In addition, the high frequency power supply board 1 is an example of the "high frequency power supply" of a claim. FIG. 1 is a schematic diagram, and members unnecessary for explanation are omitted from the illustration.

AC power is supplied from an AC power supply 101 to the high-frequency power panel 1 . The high-frequency power panel 1 also includes a rectifying section 1a that converts AC power from the AC power supply 101 into DC power. The high-frequency power panel 1 also includes a smoothing section 1b that smoothes the DC power converted by the rectifying section 1a. The high-frequency power panel 1 also includes an inverter section 1c that converts the DC power smoothed by the smoothing section 1b into AC power.

Further, the melting apparatus 100 is provided with a heating section 10 in which a heating coil section 11, which will be described later, is provided. The heating unit 10 is provided adjacent to the high frequency power panel 1 .

A heating section 10 of the melting apparatus 100 is provided with a heating coil section 11 into which the raw material to be melted 200 is inserted. Note that the raw material to be melted 200 is made of a non-magnetic material. For example, the molten raw material 200 is made of aluminum, zinc, copper, or the like. Further, the raw material to be melted 200 is configured as an ingot (a lump of refined metal). Moreover, the raw material to be melted 200 has a substantially prismatic shape (substantially cuboid shape). Further, the raw material to be melted 200 has a substantially rectangular parallelepiped shape when viewed from the direction in which the raw material to be melted 200 extends (the Z direction). Note that the melted raw material 200 is an example of the "first melted raw material" in the scope of claims.

The heating coil portion 11 is an induction heating type heating coil portion 11 . That is, magnetic flux (magnetic field) is generated from the heating coil portion 11 by the AC power supplied from the high frequency power supply board 1 . This magnetic flux generates a high-density eddy current (skin effect) in the vicinity of the surface of the melting raw material 200 inserted inside the heating coil portion 11 . The surface of the molten raw material 200 is heated by the Joule heat of this eddy current.

The melting apparatus 100 also includes a melting furnace 11 a provided in the heating section 10 . The heating coil portion 11 is wound around the melting furnace 11a, and the raw material to be melted 200 is inserted therein.

Further, the melted raw material 200 that has flowed through the through-holes 22 to be described later and dropped is held in the holding furnace 102 . By turning on the high-frequency power panel 1, the raw material to be melted 200 is started to be melted, and the raw material to be melted 200 is stored in the holding furnace . The melting of the raw material 200 is stopped by turning off the high-frequency power panel 1 at the moment when the required amount of raw material 200 is obtained.

The melting apparatus 100 includes a support section 20 arranged below the heating coil section 11 and supporting the lower end 200a of the raw material to be melted 200 from below. The support portion 20 supports the lower end 200a of the raw material to be melted 200 from below at a position above the lower end 11b of the heating coil portion 11 . Specifically, the support portion 20 includes a raw material support surface portion 21 that supports the lower end 200a of the molten raw material 200 at a position above (Z1 direction side) the lower end 11b of the heating coil portion 11 .

Specifically, the raw material supporting surface portion 21 is arranged above the lower end 11b of the heating coil portion 11 by a length L12 that is 18% or more of the length L11 of the heating coil portion 11 in the vertical direction. More preferably, the raw material supporting surface portion 21 is arranged above the lower end 11b of the heating coil portion 11 by a length L12 that is 25% or more of the length L11 of the heating coil portion 11 . As a result, the lower end 200a of the raw material to be melted 200 is positioned by the raw material supporting surface portion 21, so that the lower end 200a of the raw material to be melted 200 is positioned above the lower end 11b of the heating coil portion 11 by a distance L12.

Here, in the first embodiment, the melting furnace 11a and the support section 20 are provided separately from each other. Specifically, the support part 20 is inserted inside the melting furnace 11a. That is, the support part 20 is provided so as to be surrounded by the inner peripheral surface 11c of the melting furnace 11a. Specifically, the entire support portion 20 is surrounded by the inner peripheral surface 11c in the vicinity of the lower end portion 11d of the melting furnace 11a.

The dissolving device 100 includes a guide section 30 . The guide part 30 is attached to the melting furnace 11a. The guide part 30 inserts the molten raw material 201 into the heating coil part 11 (melting furnace 11a) in a state in which the molten raw material 201 to be melted after the molten raw material 200 is stacked so as to be in contact with the molten raw material 200. to guide you. Specifically, the guide portion 30 has a cylindrical shape. The movement (inclination) of the raw material to be melted 201 inserted into the guide portion 30 is regulated by the inner peripheral surface 31 of the guide portion 30 so as not to tilt obliquely. As the melting of the raw material 200 progresses, the raw material 201 held vertically by the guide portion 30 is guided by the guide portion 30 so as to be inserted into the melting furnace 11a while being held vertically. . The raw material to be melted 201 is inserted into the melting furnace 11 a by the guide portion 30 while being placed on the upper end surface 200 b of the raw material to be melted 200 . Also, the raw material to be melted 201 is an example of the "second raw material to be melted" in the claims.

As for the timing of placing the raw material to be melted 201 on the upper end surface 200b of the raw material to be melted 200, the raw material to be melted 200 cannot be melted unless the load applied to the heating coil portion 11 changes rapidly as the raw material to be melted 201 is placed. It may be before or after starting. As a result, it is possible to continuously melt the raw material 200 and the raw material 201 while suppressing fluctuations in the load applied to the heating coil portion 11 . Moreover, it is possible to reduce the control load by complicated control compared to the case of adjusting the timing of charging the raw material to be dissolved 201 .

Each of the support portion 20 and the guide portion 30 is made of a non-magnetic material. Specifically, the support portion 20 and the guide portion 30 are made of a non-magnetic material that is not induction-heated by the heating coil portion 11 . For example, the support portion 20 and the guide portion 30 are made of refractory bricks, heat-resistant resin, ceramics, or the like. It is desirable that the guide part 30 is made of a material having higher mechanical strength and higher heat resistance than the raw material to be melted 200 (201).

As shown in FIGS. 2 to 4, the support part 20 has a shape (substantially rectangular parallelepiped shape) along the shape of the raw material to be melted 200 .

In the first embodiment, as shown in FIG. 2, the raw material supporting surface portion 21 is configured to support the central portion C (see FIG. 8) of the lower end 200a of the molten raw material 200 in plan view. Specifically, in the vicinity of the raw material supporting surface portion 21 of the supporting portion 20, a through hole 22 is provided through which the melted raw material 200 flows and drops. The through hole 22 extends in the vertical direction (Z direction). Also, a plurality of (two in the first embodiment) through holes 22 are provided. The raw material support surface portion 21 is configured by a portion (a portion between the through holes 22a and 22b) between the plurality (two) of the through holes 22 in the support portion 20. As shown in FIG. Specifically, the molten raw material 200 before being melted is supported on the upper surface of the support portion 20 except for the through holes 22 . Further, as the melting of the raw material 200 progresses, the raw material 200 becomes tapered downward (see FIG. 8). The leading end of the tapered molten raw material 200 is supported by the raw material supporting surface portion 21 formed by the portion between the plurality (two) of the through holes 22 .

Moreover, as shown in FIG. 3, the through hole 22 has a substantially circular shape in a plan view. The diameter r of the through-holes 22 is larger than the width W of the raw material supporting surface portion 21 in the direction (X direction) in which the plurality of through-holes 22 are adjacent to each other. The two through holes 22 have the same shape (same diameter). And, for example, the diameter r is twice the width W or more. Note that the diameter r of the through-hole 22 is adjusted so that the melted raw material 200 can smoothly drop downward through the through-hole 22 . In addition, the width W is adjusted so that the tapered molten material 200 (see FIG. 7) is stably supported.

Further, as shown in FIG. 4, the length L21 of the portion of the support portion 20 that is arranged inside the heating coil portion 11 is longer than the length L22 of the portion that is arranged outside the heating coil portion 11. . Note that the length L21 is adjusted depending on the position inside the heating coil portion 11 where the raw material supporting surface portion 21 is arranged. Therefore, length L21 may be smaller than length L22. Also, the length L21 of the portion arranged inside the heating coil portion 11 is adjusted to an optimum length according to the type of the raw material to be melted 200 .

(Analysis of magnetic flux density and Joule heat density)
Next, analysis (simulation) of magnetic flux density and Joule heat density generated from the heating coil portion 11 will be described.

First, as shown in FIG. 5, the case where the height position of the lower end 200a of the raw material to be melted 200 and the height position of the lower end 11b of the heating coil portion 11 are set to be the same (substantially flush) will be described. In this case, it was confirmed that the magnetic flux density (magnetic field) in the vicinity of the lower end 200a of the raw material to be melted 200 was relatively low and the raw material to be melted 200 could not be sufficiently melted. The reason for this is considered that the magnetism is blocked by the side surface 200c of the raw material to be melted 200 and the magnetic flux does not sufficiently reach the corner 200d of the lower end 200a of the raw material to be melted 200 . That is, no edge effect occurs at the corner portion 200d, so the magnetic flux is not concentrated. Therefore, it is considered that the dissolved raw material 200 is not sufficiently dissolved and remains as a solid.

On the other hand, as shown in FIG. 6, when the lower end 200a of the raw material to be melted 200 is arranged above the lower end 11b of the heating coil portion 11 by a length of about 18% to 25% of the length of the heating coil portion 11. , the magnetic flux density at the lower end 200a of the raw material to be melted 200 is relatively high. As a result, the magnetic flux sufficiently reaches the corner portion 200d of the lower end 200a of the raw material to be melted 200, and an edge effect occurs at the corner portion 200d. As a result, it was confirmed that all of the raw material to be melted 200 could be melted because the magnetic flux was concentrated on the corner 200d.

Further, as shown in FIG. 7, it was confirmed that the Joule heat density (temperature) at the corner portion 200d is relatively high because the magnetic flux concentrates at the corner portion 200d. It should be noted that FIG. 7 shows the results of the simulation in the case where the molten raw material 200 is divided into quarters and the molten raw material 200 has a tapered shape. From FIG. 7, it was confirmed that the Joule heat density (temperature) increases as the distance from the heating coil section 11 decreases in the raw material to be melted 200 . It was confirmed that in the tapered molten material 200, the tip (corner 200d) has a large distance from the heating coil 11, but the Joule heat density (temperature) increases due to the edge effect. As a result, it was confirmed that the raw material to be melted 200 was melted from the corner 200d of the raw material to be melted 200 .

(Experiment on placement position of raw material supporting surface)
Next, an experiment conducted to confirm the state of melting of the raw material 200 with respect to the arrangement position of the raw material supporting surface portion 21 inside the heating coil portion 11 will be described.

The raw material support surface portion 21 is moved to the lower end 11b of the heating coil portion 11 by less than 18% (0%, 5%, 10%, 15%, etc.) of the length L11 (see FIG. 1) of the heating coil portion 11 in the vertical direction. It has been confirmed that when it is arranged at a position above , the raw material to be dissolved 200 cannot be sufficiently dissolved and solid raw material to be dissolved 200 remains. On the other hand, when the raw material supporting surface portion 21 is arranged at a position that is 18% or more of the length L11 of the heating coil portion 11 in the vertical direction and is above the lower end 11b of the heating coil portion 11, the raw material to be melted 200 can be sufficiently melted. confirmed.

(Experiment on Continuous Melting of Melting Raw Materials)
FIG. 9 shows an experiment conducted to confirm power fluctuations when seven melted raw materials 200 were continuously melted.

As shown in FIG. 9, when the melting raw material 200 to be melted was switched, the electric power fluctuated to some extent, but it was confirmed that the electric power was stably controlled thereafter. In particular, it was confirmed that the electric power was controlled more stably in the third and subsequent melted raw materials 200 . A possible reason for this is that the electric elements and the like included in the melting apparatus 100 begin to thermally stabilize around the time when the melting of the third melting raw material 200 is started.

Moreover, it was confirmed that the melting time required for melting one melted raw material 200 was substantially the same for all seven melted raw materials 200 . It was also confirmed that the electric power increased relatively quickly after the high-frequency power panel 1 was operated, and that the melting of the first raw material to be melted 200 started relatively quickly. Moreover, it was confirmed that the electric power decreased relatively quickly after the high-frequency power panel 1 was stopped, and the melting of the seventh raw material to be melted 200 was completed relatively quickly.

As a result, the high-frequency power panel 1 is operated at an arbitrary timing to start melting the raw material to be melted 200, and the high-frequency power panel 1 is stopped instantaneously when the required amount of raw material to be melted 200 is obtained. It becomes easy to melt the raw material 200 to be melted in the required amount at the required time and to take it out from the melting device 100 . As a result, it is not necessary to hold and keep warm a large amount of raw material 200 to be melted in the holding furnace 102 . This makes it possible to make the size of the holding furnace 102 relatively small. Further, it is possible to directly supply the molten raw material 200 from the melting apparatus 100 to a die casting machine (not shown) without providing the holding furnace 102 .

(Operation of melting device)
Next, operation of the dissolving device 100 will be described.

First, the breaker (not shown) of the high frequency power panel 1 (see FIG. 1) is turned on. This prepares for operation. Heating by the heating coil portion 11 is started by operating an operation portion (not shown) provided on the high-frequency power supply board 1 .

Then, as shown in FIG. 8(a), the melting starts from the outer surface of the raw material 200 due to the skin effect. The molten raw material 200 that has been melted falls downward (outside the heating coil section 11 ) through the through holes 22 of the support section 20 . Also, due to the skin effect, the central portion C of the molten raw material 200 melts slower than the outer surface of the molten raw material 200 . Accordingly, as the melting of the raw material 200 progresses, the raw material 200 becomes tapered downward. Then, the tapered leading end portion of the raw material 200 is supported by the raw material supporting surface portion 21 .

As the melting progresses further, the edge effect (see FIG. 7) causes the magnetic flux to concentrate at the tip of the tapered melting raw material 200 . As a result, the tip of the raw material to be melted 200 is melted. As a result, as shown in FIG. 8B, the melted raw material 200 descends due to its own weight. In addition, since the lowered molten raw material 200 is supported by the raw material support surface portion 21 of the support portion 20, the lowered molten raw material 200 is stopped. By continuing to supply the high-frequency current to the heating coil portion 11, the state shown in FIG. 8A and the state shown in FIG. 8B are alternately repeated. Thereby, the raw material to be melted 200 is continuously melted.

Here, when the supply of the high-frequency current to the heating coil portion 11 is stopped, the heating of the raw material to be melted 200 is immediately stopped (within several seconds). As a result, the descent of the melted raw material 200 is stopped instantaneously. Further, when the supply of the high-frequency current to the heating coil portion 11 is resumed while the raw material to be melted 200 is at a relatively high temperature, melting immediately begins, and the melted raw material to be melted 200 resumes falling. By controlling the supply time of the high-frequency current to the heating coil portion 11 in this way, it is possible to control the amount of the raw material 200 to be melted.

Further, unlike the first embodiment, when the raw material to be melted 200 is melted by directly applying the flame of the burner to the raw material to be melted 200, the raw material to be melted 200 is oxidized by the gas (oxygen, hydrogen) contained in the flame. (oxidation loss). As a result, the yield of melting deteriorates. Furthermore, additional energy is required to keep the melted raw material 200 (molten metal) in a liquid state, and personnel are also required to monitor the state of the molten metal. Therefore, in the first embodiment, the melting raw material 200 is not oxidized by melting the raw material 200 by the heating coil section 11 supplied with the high-frequency current, so that the yield of melting is improved (the quality is maintained). ) becomes possible. Also, it is possible to reduce the energy required to keep the molten metal in a liquid state.

Further, unlike the first embodiment, when the raw material to be melted 200 is melted by directly applying the flame of the burner to the crucible containing the raw material to be melted 200, the flame of the burner can uniformly heat the surface of the crucible. Have difficulty. As a result, the temperature distribution of the crucible is biased. As a result, the crucible is partially worn, requiring maintenance of the crucible. In addition, since the raw material to be melted 200 is indirectly heated through the crucible, the consumption of gas, oil, etc., which is the raw material for the flame of the burner, increases. Therefore, in the first embodiment, the raw material to be melted 200 can be directly heated by melting the raw material to be melted 200 by the heating coil section 11 to which the high-frequency current is supplied, thereby suppressing an increase in energy consumption. it becomes possible to

[Effect of the first embodiment]
The following effects can be obtained in the first embodiment.

In the first embodiment, as described above, the through hole 22 through which the melted raw material 200 flows and drops is included, and the lower end 200a of the raw material 200 is positioned above the lower end 11b of the heating coil section 11. and a guide portion 30 for guiding the molten raw material 201 to be inserted into the heating coil portion 11 in a state where the molten raw material 201 is stacked so as to be in contact with the molten raw material 200. , the dissolving device 100 is configured. As a result, since the lower end 200a of the raw material to be melted 200 is positioned above the lower end 11b of the heating coil portion 11, the magnetic flux from the heating coil portion 11 is applied to the lower end 200a of the raw material to be melted 200 and the portion near the lower end 200a. enough to reach. As a result, the lower end 200a of the raw material to be melted 200 and the portion in the vicinity of the lower end 200a can be rapidly melted, so that clogging of the through hole 22 by the unmelted residue of the lower end 200a of the raw material to be melted 200 can be suppressed. As a result, the melted raw material 200 can smoothly flow out from the through hole 22, and the melted raw material 200 can be prevented from scattering. As a result, it is possible to prevent the scattering raw material 200 from adhering to the raw material 201 . Here, when the raw material to be melted 201 is inserted into the heating coil portion 11 in a state where the raw material to be melted 201 is stacked so as to be in contact with the raw material to be melted 200, the magnetic flux from the heating coil portion 11 does not reach the raw material to be melted 201, and the raw material to be melted does not reach the raw material to be melted. 201 may be cold. However, even in this case, since scattering of raw material 200 is suppressed, adhesion of scattered raw material 200 to raw material 201 is suppressed. You can avoid getting in the way. As a result, in order to bring the raw material to be melted 201 into a heated state when the raw material to be melted 201 is inserted, the timing is set so that the raw material to be melted 201 is melted and reduced to a predetermined size before the raw material to be melted 201 is inserted. No need to control. That is, even when the raw material to be melted 201 is stacked on the raw material to be melted 200 using the guide portion 30 and inserted into the heating coil portion 11 before the raw material to be melted 200 is melted and reduced to a predetermined size, the raw material to be melted 201 can be melted smoothly. can be inserted into the heating coil portion 11 at any time. As a result, the size of the object to be heated by the heating coil portion 11 can be made substantially constant. As a result, the load applied to the heating coil portion 11 can be kept substantially constant. As a result, the raw material to be melted 200 and the raw material to be melted 201 can be stably and continuously melted.

Further, in the first embodiment, as described above, the melting apparatus 100 is configured such that the melting furnace 11a and the support section 20 are provided separately from each other. Thereby, each of the melting furnace 11a and the support part 20 can be individually replaced, so maintenance of each of the melting furnace 11a and the support part 20 can be facilitated. Moreover, since the size (height) of the support part 20 can be changed by exchanging the support part 20, the melting characteristics (dissolution rate, etc.) of the raw material 200 can be easily adjusted.

In addition, in the first embodiment, as described above, the melting apparatus 100 is configured so that the support portion 20 is provided so as to be surrounded by the inner peripheral surface 11c of the melting furnace 11a. As a result, the movement of the support portion 20 is restricted by the inner peripheral surface 11c of the melting furnace 11a, so that the position of the support portion 20 can be suppressed from shifting.

In addition, in the first embodiment, as described above, the melting apparatus 100 is configured so that each of the support portion 20 and the guide portion 30 is made of a material that is non-magnetic and is not induction-heated by the heating coil portion 11. configure. As a result, the magnetic flux from the heating coil portion 11 can be suppressed from being affected by the support portion 20 and the guide portion 30, so that the raw material to be melted 200 can be stably melted by the heating coil portion 11.

Further, in the first embodiment, as described above, the melting apparatus 100 is configured such that the raw material supporting surface portion 21 supports the central portion C of the lower end 200a of the raw material to be melted 200 in plan view. Here, when the molten raw material 200 is heated by the magnetic flux of the heating coil portion 11, the surface of the molten raw material 200 is mainly heated by the skin effect. As a result, melting starts from the outer surface of the raw material to be melted 200, and the central portion C of the raw material to be melted 200 is melted at a relatively late stage. In other words, melting progresses gradually from the outer surface of the raw material 200 toward the center. Furthermore, since the magnetic flux concentrates on the lower end 200a (corner portion 200d) of the raw material to be melted 200, the degree of progress of melting on the lower end 200a side is rapid. As a result, the melted raw material 200 has a shape that tapers downward. Therefore, by configuring the raw material support surface portion 21 so as to support the central portion C of the lower end 200a of the molten raw material 200, the tapered front end (lower end 200a) side of the molten raw material 200 can be supported in a stable state. .

Further, in the first embodiment, as described above, the melting device 100 is configured such that the raw material support surface portion 21 is configured by the portion between the plurality of through holes 22 in the support portion 20 . Thereby, a plurality of through holes 22 are provided so as to be adjacent to the raw material supporting surface portion 21 . Since the molten raw material 200 melted from the molten raw material 200 flows toward the tip side of the tapered molten raw material 200 (the portion in contact with the raw material support surface portion 21), the molten raw material 200 is supported by the raw material support. It can be dropped more smoothly from the plurality of through holes 22 adjacent to the surface portion 21.例文帳に追加

[Second embodiment]
Next, with reference to FIG. 10, the configuration of the dissolving device 300 according to the second embodiment will be described. In the melting apparatus 300 of the second embodiment, unlike the first embodiment in which the high-frequency power panel 1 is manually turned on and off, the high-frequency power panel 1 is automatically turned on and off. In addition, the structure similar to the said 1st Embodiment attaches|subjects the same code|symbol as 1st Embodiment, and abbreviate|omits description while it is illustrated.

As shown in FIG. 10 , the melting device 300 includes a control device 40 that controls the operation of the high frequency power panel 1 .

(Determination of dissolution time of raw material to be dissolved)
Next, the control when determining the melting time T of the raw material to be melted 200 will be described.

In the second embodiment, the melting apparatus 100 (control device 40) is configured such that the power supplied from the high-frequency power panel 1 to the heating coil section 11 is set to be substantially constant, and the preset melting amount of the raw material 200 is determined. and the amount of power supplied from the high-frequency power panel 1, the melting time T of the raw material 200 to be melted by the heating coil section 11 is determined.

Specifically, the melting time T (s) is defined by A (kg) as the melting amount of the melting raw material 200 set in advance, and B (kg/ s), it is calculated by the following formula (1).

Then, melting of the raw material to be melted 200 is automatically executed (feedforward control) for the calculated melting time T. Specifically, the dissolution start time t1 is programmed in advance, and the dissolution is automatically stopped at time t2 (t1+T) after the dissolution time T from the dissolution start time t1.

Other configurations of the second embodiment are the same as those of the first embodiment.

(Effect of Second Embodiment)
The following effects can be obtained in the second embodiment.

In the second embodiment, as described above, while the power supplied from the high-frequency power panel 1 to the heating coil unit 11 is set substantially constant, the preset melting amount of the raw material 200 and the high-frequency power panel 1 The melting apparatus 100 is configured so as to determine the melting time T of the raw material 200 to be melted by the heating coil section 11 based on the relationship with the amount of power supplied from the heating coil section 11 . As a result, the required amount of the raw material 200 to be dissolved can be dissolved without detecting the amount of dissolution by a weight sensor or the like. As a result, the number of parts for melting the raw material 200 can be reduced. Moreover, the control for melting the raw material 200 can be simplified as compared with the case where the power of the high-frequency power panel 1 is controlled (feedback control) based on the melting amount.

Further, since the amount of power supplied from the high-frequency power panel 1 is substantially constant, the control load for determining the melting time T of the raw material to be melted 200 can be reduced compared to the case where the amount of power supplied fluctuates. . In addition, the dissolution time T can be calculated more accurately and quickly than when the user manually calculates (determines) the dissolution time T.

Other effects of the second embodiment are the same as those of the first embodiment.

[Modification]
It should be noted that the embodiments disclosed this time should be considered as examples and not restrictive in all respects. The scope of the present invention is indicated by the scope of the claims rather than the description of the above-described embodiments, and includes all modifications (modifications) within the meaning and scope equivalent to the scope of the claims.

Moreover, although the support part 20 showed the example which has the two through-holes 22 in the said 1st and 2nd embodiment, this invention is not limited to this. The support portion 20 may be provided with one through-hole 22 or three or more through-holes 22 .

For example, as shown in FIGS. 11 and 12, the dissolving device 400 has a support portion 120 having one through hole 122 . In this case, the molten raw material 200 is supported by the raw material supporting surface portion 121 (see FIG. 12) in the vicinity of the through hole 122 .

Also, a columnar portion may be provided near the center of one through hole. Specifically, as shown in FIG. 13 , support portion 220 includes through hole 222 and columnar portion 223 . The columnar portion 223 is provided near the center of the through hole 222 . The columnar portion 223 has a raw material supporting surface portion 221 that supports the lower end 200a (see FIG. 1) of the molten raw material 200. As shown in FIG. Also, the columnar portion 223 is connected to the inner peripheral surface 222a of the through hole 222 by a pair of beam portions 224 .

Moreover, although the guide part 30 showed the example which has a cylindrical shape in the said 1st and 2nd embodiment, this invention is not limited to this. As long as the raw material to be melted 201 (second raw material to be melted) is stacked so as to be in contact with the raw material to be melted 200 (first raw material to be melted), the guide portion 30 may have a shape other than a cylindrical shape.

Moreover, although the support part 20 showed the example comprised by the refractory brick in the said 1st and 2nd embodiment, this invention is not limited to this. For example, the support portion 20 may be made of ceramics.

Further, in the above-described second embodiment, the melting of the raw material to be melted 200 (the first raw material to be melted) is automatically performed (feedforward control) for the calculated melting time T, but the present invention is similar to this. is not limited to For example, the dissolution time T may be configured to be manually settable.

Further, in the above-described first and second embodiments, an example in which the melting apparatus of the present invention is used to melt the raw material to be melted 200 (first raw material to be melted) is shown, but the present invention is not limited to this. For example, by relatively reducing the amount of high-frequency current supplied, the melter of the present invention can be used as a preheating device for removing moisture and oil adhering to the surface of the melted raw material 200 (first melted raw material) or as a heating device for raw materials such as aluminum. A device can be used.

Further, in the above-described first and second embodiments, an example in which the raw material to be melted 200 (first raw material to be melted) has a substantially rectangular parallelepiped shape (prism shape) is shown, but the present invention is not limited to this. For example, the molten raw material 200 (first molten raw material) may have a substantially cylindrical shape. In this case, the heating coil portion 11 and the raw material to be melted 201 (second raw material to be melted) are also formed to have a substantially circular shape in plan view along the raw material to be melted 200 (first raw material to be melted) having a substantially cylindrical shape. be.

Further, in the above-described first and second embodiments, an example in which the through hole 22 provided in the support portion 20 has a substantially circular shape was shown, but the present invention is not limited to this. For example, the through-hole provided in the support may have a square shape.

1 High-frequency power panel (high-frequency power supply)
Reference Signs List 11 heating coil portion 11a melting furnace 11b lower end 11c inner peripheral surface 20 support portion 21, 221 raw material supporting surface portion 22, 122, 222 through hole 30 guide portion 100 melting device 200 raw material to be melted (first raw material to be melted)
200a lower end 201 raw material to be melted (second raw material to be melted)
C central part T dissolution time

Claims (7)

a heating coil section into which the first molten raw material is inserted;
a support portion that includes a through-hole through which the first melted raw material flows and drops, and that supports the lower end of the first molten raw material from below at a position above the lower end of the heating coil;
The second molten raw material, which is melted after the first molten raw material is melted, is stacked so as to be in contact with the first molten raw material, and the second molten raw material is inserted into the heating coil section. and a guide portion for guiding ,
The support part supports the lower end of the first molten raw material at a position above the lower end of the heating coil part by a length of 18% or more of the length of the heating coil part in the vertical direction. including
The melting device , wherein the lower end of the through hole is arranged below the lower end of the heating coil portion . further comprising a melting furnace in which the heating coil portion is wound, the first melting raw material is inserted, and the guide portion is attached;
2. The melting apparatus according to claim 1, wherein said melting furnace and said support are provided separately from each other. 3. The melting apparatus according to claim 2, wherein said support portion is provided so as to be surrounded by the inner peripheral surface of said melting furnace. The dissolving device according to any one of claims 1 to 3, wherein each of said support portion and said guide portion is made of a non-magnetic material. a high-frequency power source that supplies power to the heating coil ;
A control device that controls the operation of the high-frequency power supply ,
In a state in which the power supplied from the high-frequency power source to the heating coil unit is set substantially constant, based on the preset relationship between the melting amount of the first melting raw material and the power supply amount from the high-frequency power source is configured to determine the melting time of the first melting raw material by the heating coil portion,
5. The control device according to any one of claims 1 to 4 , wherein the control device is configured to control the high-frequency power source so as to melt the first raw material for the determined melting time. dissolution device. 6. The melting apparatus according to any one of claims 1 to 5, wherein the raw material supporting surface portion is configured to support a central portion of the lower end of the first molten raw material in plan view. A plurality of the through holes are provided,
7. The dissolving apparatus according to claim 6, wherein said raw material support surface portion is configured by a portion between said plurality of through holes in said support portion.

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