JP4494868B2 - Non-ferrous metal casting feeder - Google Patents

Description

  The present invention relates to a feeder device provided as a means for preventing shrinkage in a casting apparatus using a sand mold or the like, and more specifically, a feeder for nonferrous metal casting used in an apparatus for casting nonferrous metals such as aluminum, zinc, and magnesium. It relates to a hot water apparatus.

The feeder technology is indispensable as a means to prevent shrinkage in principle and to secure a high yield of good products, but on the other hand, it costs casting costs even to the feeder part cut off after casting. There was also a disadvantage.
In the inventions described in Patent Documents 1 and 2, a cylindrical hot-water feeder housing portion made of a thin non-metallic refractory material is arranged to form the hot-water feeder portion, and an induction coil ( A technology that allows the molten metal in the hot water container to be maintained at a stable temperature by an internal heating method that directly heats the molten metal in the hot water container with an inductor), so that the hot water function is fulfilled while being slim. It is about.

  In this technique, the hot metal container is made of a non-metallic refractory and does not use a metal material, and the peripheral wall is magnetic flux permeable. Can be implemented without receiving interruption of magnetic flux by the feeder housing portion. In addition, the material of the above-described feeder housing portion is sufficiently durable without melting damage to a high-temperature molten metal of 1500 ° C. class such as cast iron. Of course, it can withstand 1000 ° C class and several 100 ° C class non-ferrous metals such as copper, aluminum and zinc.

  That is, there is no restriction | limiting regarding the material of a cast metal in the feeder technique described in the said patent document. In the above-mentioned patent documents, as the refractory hot water container housing portion, a double structure, a reverse V-shaped punch taper, or conductivity (however, several orders of magnitude smaller than metal) are used. A graphite-based refractory product is disclosed. Further, as a method for controlling the molten metal temperature, a method is also disclosed in which the temperature of the top surface of the molten metal is measured with a radiation thermometer and this is fed back to the power feeding system.

JP 9-314310 A JP-A-11-33678

  In such a conventional non-ferrous metal casting feeder, the amount and removal man-hours of the feeder are reduced by an order of magnitude (for example, 300 kg → 9 kg), resulting in a significant cost reduction and environmental improvement in the casting operation. With the expansion of the use of non-ferrous metal cast members such as aluminum, further improvements are required. In other words, when the metal to be cast has a large electric resistance (volume specific resistance) such as cast iron or copper alloy and a large Joule heat generation due to induction current, direct induction heating of the molten metal can be performed efficiently. However, there is little waste of high-frequency energization, and a relatively small and inexpensive power supply system consisting of a high-frequency power source, high-frequency output water-cooled cable, and cooling water circulation device is sufficient, whereas the cast metal is made of molten metal such as an aluminum alloy. In the case of a non-ferrous metal having a small electric resistance, direct induction heating of the molten metal cannot be efficiently performed for the reverse reason, and a large power supply system must be used.

Therefore, an improved technique is required that can efficiently heat the non-ferrous metal feeder using induction heating with excellent control response. Indirect induction heating comes to mind, such as adopting an iron-based metal and inductively heating it to transfer the heat to the internal feeder.
However, such indirect induction heating using heat transfer is incompatible with a feedback-type molten metal temperature control method in which the top surface temperature of the hot metal is measured with a radiation thermometer and fed back. This is because it is theoretically possible to accurately measure the temperature of the top surface of the hot water that is displaced up and down without being confused with the hot water container that is hotter than the hot water through the hollow of the slender cylindrical hot water container. Because it is difficult.

Therefore, as a technique for performing induction heating of the feeder with a small and inexpensive power supply system, even when the cast metal is a non-ferrous metal, even with indirect induction heating using heat transfer, An open control method in which the temperature itself does not need to be measured, for example, a molten metal temperature control method using a magnetic transformation point (A ₂ point) is conceivable. That is, as a ferromagnetic metal (steel material, etc.) constituting the feeder housing part, a material whose magnetic transformation point is adjusted to a control target temperature is used, so that the temperature rises to a target temperature or higher. It is a technique of suppressing the above.

However, there are a wide variety of non-ferrous metals to be cast, and accordingly, an appropriate value of the molten metal temperature of the hot metal is not determined. For this reason, in order to open-control the hot metal temperature based on the magnetic transformation point, it is necessary to prepare other types of steel materials and the like whose composition is changed so that the magnetic transformation point is gradually different. However, most of the steel materials with such a desired composition, except for some, are custom-made products that are not commercially available / distributable. Is too expensive. That is, if the hot water temperature open control method using the magnetic transformation point is simply adopted, the cost merit of indirect induction heating is lost.
Therefore, even if the metal to be cast is a non-ferrous metal, the cylindrical feeder unit and the inductor are connected to the heat transfer type so that induction heating of the feeder can be performed with a small and inexpensive power supply system as in the case of iron type. In addition to providing the technology, it is necessary to provide a technology that can take advantage of the cost merit of indirect induction heating using heat transfer and accurately control the hot water temperature.

The hot water feeder for non-ferrous metal casting according to the present invention (initial claim 1) has been devised to solve such a problem, and is erected in communication with a mold to melt a molten metal of a cast metal. In a non-ferrous metal casting hot-water device comprising a cylindrical hot-water container accommodating portion that can be freely positioned and a molten metal heating mechanism for inputting heat into the molten metal in the hot-water container portion, A composite cylindrical body provided with a heat transfer adjusting layer made of a non-metallic refractory material is arranged on the inner peripheral surface of the ferromagnetic metal mother cylinder, and the molten metal heating mechanism is arranged on the outer periphery of the composite cylindrical body. It is characterized by comprising a mother cylinder induction heating mechanism provided with an inductor arranged on the side for induction heating of the mother cylinder and a power feeding system for applying high frequency current to the inductor.
Here, as the ferromagnetic metal, an iron-based metal that is most advantageous in terms of cost and availability is preferable, but a nickel (magnetic transformation point≈360 ° C.) system or a cobalt (magnetic transformation point≈1130 ° C.) system, that is, Other iron group element-based metals can be used as needed.

Further, a feeder for casting non-ferrous metal according to the present invention (initial claim 2) is the feeder for casting non-ferrous metal according to claim 1 described above, and the heat transfer adjusting layer further comprises this layer. The material and thickness are set so that the temperature drop in heat transfer in the penetrating direction is 50 to 250 ° C.
Furthermore, a feeder for casting nonferrous metal according to the present invention (initial claim 3) is the feeder for casting nonferrous metal according to the first and second claims, wherein the heat transfer adjusting layer is non- It is characterized by being coated with a refractory thick film paint mainly composed of metal-based refractory material fibers or particles.

Further, a feeder for casting non-ferrous metal according to the present invention (initial claim 4) is the feeder for casting non-ferrous metal according to claims 1 to 3, further comprising a thickness of the heat transfer adjusting layer. Is set to 2 to 20 mm.
Further, the feeder for casting non-ferrous metal of the present invention (initial claim 5) is the feeder for casting non-ferrous metal according to the first to fourth aspects of the present invention, and the cooling means for the inductor further comprises: It is characterized by cooling or blowing cooling under a configuration in which a heat insulating layer is interposed between the inductor and the composite cylinder to insulate from the composite cylinder.
Further, the feeder for casting non-ferrous metal according to the present invention (initial claim 6) is the feeder for casting non-ferrous metal according to the above-mentioned initial claims 1-5, and further, A plurality of the composite cylinders are densely arranged in a forested area at one place of the hot water storage part.

A non-ferrous metal casting feeder according to the present invention (initial claim 7) is the non-ferrous metal casting feeder according to the above-mentioned initial claim 6, and the inductor is composed of the plurality of composites. It is wound in a form that comprehensively surrounds the cylinder.
Further, a feeder for casting non-ferrous metal according to the present invention (initial claim 8) is the feeder for casting non-ferrous metal according to claims 1 to 7 above, and the inductor further comprises the feeder. A partial section extending over the lower end of the housing portion is installed at a position in the vertical direction that is a non-heating target section.
A feeder for casting non-ferrous metal according to the present invention (initial claim 9) is the feeder for casting non-ferrous metal according to claims 1 to 8, wherein the inductor is further positioned in the vertical direction. It is possible to adjust the section length of the non-heating target section by making the variable.

  In such a feeder for casting non-ferrous metal according to the present invention (initial claim 1), the feeder housing portion is composed of a composite cylinder, and the ferromagnetic metal mother cylinder is disposed on the outer peripheral side. By inductive heating with the inductor of Joule heat generation, and by transferring the heat to the melt inside through the heat transfer adjustment layer, by the property of the induction heating of the ferromagnetic metal efficiently, Even if the metal to be cast is a non-ferrous metal, it is possible to obtain a merit that a heat generation level in the feeder section is secured at a high level with a small and inexpensive power feeding system as in the case of iron. In addition, a heat transfer adjusting layer made of a non-metallic refractory material is provided on the inner peripheral surface of the mother cylinder so as to be interposed between the inner molten metal and the interior of the feeder housing part. Thus, a heat transfer system is formed in which the heat resistance provided by the heat transfer adjustment layer is added in series to the heat resistance of the molten metal.

  The heat resistance of the molten metal is sufficiently small due to the high heat conductivity inherent to the metal and the heat transfer due to convection, whereas the heat resistance of the heat transfer adjustment layer is the low heat conductivity inherent to the nonmetallic refractory (metal As long as this heat transfer adjustment layer is not a thin layer of several hundred μm, it is much larger than the thermal resistance of the molten metal. As a result, the mother cylinder that is a heat generation source is in a state of functioning as a constant heat flow heat generation source for the molten metal that is a heat receiving body. This means that the temperature drop from the mother cylinder to the molten metal can be maintained at a constant value corresponding to the heat resistance of the heat transfer adjustment layer. In other words, since the initial movement of the temperature change of the molten metal and the initial movement of the temperature change of the mother cylinder are linked with a constant temperature difference, the temperature of the molten metal is constant if the temperature of the mother cylinder is kept constant. It is to be kept in.

That is, the temperature control of the molten metal in the feeder housing part can be performed by controlling the temperature of the mother cylinder which is easy to control. As a method for controlling the mother body temperature, open control using the magnetic transformation point (A ₂ point) is recommended. This is because in the device of the present invention, the conventional pinpoint setting of the magnetic transformation point for the open control is not necessary, and ordinary steel (magnetic transformation point ≈ 780 ° C.) that can be readily obtained at a low cost, Alternatively, if the mother cylinder is made of ferritic or martensitic stainless steel (magnetic transformation point is 730 to 600 ° C.) or the like according to this, an aluminum alloy (feeding temperature 600 to 650 ° C.) or a zinc alloy (pressing This is because open control management of the hot water temperature such as the hot water temperature (450 to 550 ° C.) can be performed.

Incidentally, the adjustment of the heat resistance value of the heat transfer adjustment layer for compensating for the temperature difference between the magnetic transformation point and the hot water temperature can be easily performed by experimentally selecting the material and thickness. Needless to say, the control of the mother cylinder temperature may be feedback control based on the mother cylinder temperature measurement data. In short, it is only necessary to control the temperature of the molten metal based on the temperature of the mother cylinder, which is easy to control, rather than the temperature of the molten metal itself.
As described above, according to the present invention, it is possible to realize a non-ferrous metal casting hot water supply device that can take advantage of the cost merit of indirect induction heating using heat transfer and finely control the hot water temperature.

  Moreover, in the hot water feeder for non-ferrous metal casting of the present invention (initial claim 2), the heat resistance of the heat transfer adjusting layer is set to be equal to or higher than a level that causes a temperature drop of 50 ° C., Ensuring that the mother cylinder functions as a constant heat flow heat source with respect to the molten metal, on the other hand, by making the thermal resistance below a level that causes a temperature drop of 250 ° C., the energy associated with this temperature drop It is possible to avoid an excessive loss and, in turn, a situation in which a request for enlargement of the power supply system is reoccurred, thereby eliminating a cost demerit factor.

  Furthermore, in the feeder for casting non-ferrous metal according to the present invention (initial claim 3), the heat transfer adjusting layer is formed by applying fibers or particles of non-metallic refractory material. In-situ construction of the heat transfer adjustment layer, in-situ removal after in-use wear and in-situ renewal construction, and further, thickness adjustment for providing the heat resistance with the desired value in the heat transfer adjustment layer becomes extremely easy. .

Moreover, in the hot water feeder for nonferrous metal casting of the present invention (initial claim 4), the thickness of the heat transfer adjustment layer is set to 2 to 20 mm, so that the temperature drop due to the heat transfer adjustment layer is reduced to 50%. It can be made into a suitable range that satisfies ˜250 ° C.
In addition, in the feeder for casting non-ferrous metal according to the present invention (initial claim 5), the cooling means for the inductor is allowed to cool or blown in combination with heat insulation from the mother cylinder that is the main heat source. By adopting (by an electric fan or the like), complicated and costly water cooling of the inductor is eliminated by a heat insulating treatment that does not require cost.

  Further, in the hot water feeder for non-ferrous metal casting according to the present invention (initial claims 6 and 7), the hot water container is configured by arranging a plurality of composite cylinders at one place of the hot water container. In addition, by reducing the cross-sectional area of the feeders related to various composite cylinders, in the casting that requires a large feeder cross-sectional area, cutting of the feeder part after solidification is sequentially cut off the small-diameter feeder part. It can be done efficiently. By the way, in the casting of non-ferrous metal, for example, in the casting of aluminum, there is a circumstance that a large feeder cross section is required due to the tendency to shrinkage due to a particularly large solidification shrinkage rate, or steel material Reducing the excision of the feeder has great cost merit, such as the fact that it is difficult to remove the feeder due to the combination of hard carbide fine particles to compensate for the weakness of being soft compared to become.

  In addition, induction heating of the feeder housing part is performed by an inductor wound in a form that comprehensively surrounds the plurality of pieces, so that induction is performed even though there are a plurality of composite cylinders. Since a set of the child and the power supply system is sufficient, the cost increase can be reduced. For this reason, a difference in cooling conditions is unlikely to occur between a plurality of densely arranged composite cylinders (especially in the case where a heat insulating layer is comprehensively interposed between inductors). The mother cylinder of the hot water storage section is substantially the same and equal. Furthermore, as will be described later, in the case where the mother body temperature is the open control using the magnetic transformation point, the above uniformity is ensured more precisely.

  Furthermore, in the feeder for casting non-ferrous metal of the present invention (initial claims 8 and 9), a part of the section over the lower end of the feeder housing portion is a non-heated section where the effect of the inductor does not reach. Thus, a temperature gradient is generated in this section in which the temperature decreases toward the lower end side. In addition, since this section occupies the downstream area of the constant heat flow heat transfer path that penetrates the heat transfer control layer, it is also a constant heat flow heat transfer path and has a non-negligible section length. As a result, if the molten metal temperature in the heating section above this section is kept constant by the basic construction technique of the present invention (initial claim 1), the molten metal temperature at the lower end of the section is also It is maintained almost constant.

In other words, it is possible to control the temperature of the molten metal at the lower end of the hot metal part that is in direct contact with the molten metal in the mold, which is a cast product, and to ensure high quality of the cast product (shape quality, solidification structure, etc.). It is.
In addition, the length of the non-heating section can be adjusted by making the vertical positioning of the inductor variable, so that the optimization of the molten metal temperature at the lower end of the hot metal part by optional selection of the above temperature difference has been studied experimentally. It will be realized after a while.

  A configuration of an embodiment of a feeder for casting nonferrous metal according to the present invention will be described with reference to the drawings. 1A is an external perspective view of the entire apparatus, FIG. 1B is a plan view of a fitting object between a cylindrical feeder housing part and an inductor, and FIG. d) is a cross-sectional view of the coil wire of the high-frequency coil.

  The non-ferrous metal casting feeder 10 (see FIG. 1A) includes a tubular feeder housing 20 and a molten metal heating mechanism 30 + 40. The hot-water container 20 is used while standing in communication with the mold, and in that state, the molten non-ferrous metal is accommodated in such a manner that the molten metal surface can be freely positioned. Further, in order to facilitate extraction for reuse, it is formed in an inverted V-shaped (tapered) cylindrical body having a thick lower end and a thin upper end. The molten metal heating mechanism 30 + 40 (master cylinder induction heating mechanism) is an inductor for induction heating the hot metal container 20 in order to perform heat input to the molten metal in the hot metal container 20 by indirect induction heating using heat transfer. 30 and a power feeding system 40 for energizing the inductor 30 with high frequency.

  The power feeding system 40 (see FIG. 1A) includes a high frequency power source 42 that combines a cooling water circulation device 43 and a high frequency output water cooling cable 41 that connects the inductor 30 and the inductor 30 so that power can be fed. In addition, high-frequency energization can be performed at a frequency of about 1 to 400 kHz. The output of the high frequency power source 42 is about 0.5 to 5 kW. The output control is open control without temperature feedback.

The inductor 30 and the cylindrical hot water container 20 (see FIGS. 1B and 1C) have an outer diameter of the hot water container 20 in order to enable a necessary fitting state during induction heating. It is formed to be slightly thinner than the inner diameter of the inductor 30, and the feeder 30 is covered with the inductor 30 and arranged concentrically.
The hot water container 20 itself is a composite cylinder, a mother metal body 21 made of a ferromagnetic metal is arranged on the outer peripheral side, and a heat transfer adjustment layer 22 made of a nonmetallic refractory material is provided on the inner peripheral side. It is arranged in. The size of the hot-water container 20 varies depending on the type of non-ferrous metal, the mold size, etc., but it cannot be said unconditionally, but typical examples include an inner diameter of 20 to 30 mm, an outer diameter of 30 to 40 mm, and a height. Is about 200 mm.

  The heat transfer adjusting layer 22 is formed by applying non-metallic refractory material fibers or granular materials to the inner peripheral surface of the mother cylinder 21 and the thickness thereof is selected in the range of 2 to 20 mm. The non-metallic refractory material may be known as long as it is suitable for coating (see, for example, the pipe materials in Patent Documents 1 and 2), but considering the suitability for thickening, high-temperature strength, and durability against non-ferrous metal to be cast A fire-resistant paint having glass fiber as a main component and solidified with an alumina-silica binder is suitable. In addition, it is good also as a structure which fitted the preformed cylinder (sleeve made from a fireproof cloth, etc.) rather than the above coating formats. In this case, it is preferable to achieve good heat transfer with the mother cylinder by applying the binder or the like to the meeting surface with the mother cylinder.

  The mother cylinder 21 is formed by processing a ferromagnetic metal into a tapered cylinder, and has a thickness of about 2 to 20 mm. The ferromagnetic metal constituting the mother cylinder 21 is commercially available at a low price from among iron group elemental metals (steel materials, etc.) having a magnetic transformation point 50 to 250 ° C. higher than the melting point of the non-ferrous metal to be cast. Is selected and adopted. Examples that are easy to use at present are carbon steel (ordinary steel) having a magnetic transformation point of about 780 ° C., 13Cr stainless steel (eg, martensitic SUS410) of about 700 ° C., 18 to about 630 ° C. to about 600 ° C. 19Cr stainless steel (for example, ferritic SUS430, SUS444) and the like.

  For example, in the case where the desired melting temperature of the cast non-ferrous metal is in the range of 600 to 650 ° C. (aluminum alloy, magnesium alloy, etc.), the mother cylinder 21 is made of carbon steel (magnetic transformation point≈780 ° C.). The heat transfer adjustment layer is made thick (for example, 10 to 20 mm) after being used, or the heat transfer adjustment layer is made thin (for example, 2 to 20 mm) after using one made of 13Cr stainless steel (magnetic transformation point≈700 ° C.). 10 mm). Similarly, in a case where the desired molten metal temperature is in the range of 400 to 500 ° C. (such as zinc alloys), a mother cylinder made of 18 to 19 Cr stainless steel (magnetic transformation point≈630 to 600 ° C.) may be used. In cases where the desired molten metal temperature is 300 ° C. or lower (such as tin or lead), Ni-based metals are also useful as the parent cylinder material.

  The inductor 30 is mainly composed of a high-frequency coil 33, but also includes a fire-resistant coil support member 31 that stores and supports the coil 30, and a heat insulating material 32 that is attached to the entire inner peripheral surface of the inductor 30. The coil support member 31 is made of a hard electrical insulating material such as a bakelite-based resin material, but the heat insulating material 32 is made of, for example, a soft calcium silicate fiber-based mat material, and the thickness thereof is about 20 mm. It is thicker than the heat transfer adjustment layer 22. The heat insulating material 32 may be attached to the outer peripheral surface of the mother cylinder 21 by distributing approximately half of the heat insulating material 32. A heat-resistant electric wire is used for the high-frequency coil 33, and the high-frequency coil 33 is wound in a spiral / cylindrical shape, and both energization ends thereof are connected to the high-frequency output water-cooled cable 41. As the heat-resistant electric wire of the high-frequency coil 33 (see FIG. 1D), for example, a wire in which a large number of copper thin wires 34 are covered with a heat-resistant coating 35 such as polyimide or glass cloth is used. It can be easily done.

  About the hot-water supply apparatus for nonferrous metal casting of this embodiment, the use aspect and operation | movement are demonstrated referring drawings. 2A is an external perspective view of the mold 50 and the like, and FIGS. 2B to 5F are longitudinal sectional views of the mold 50 and the like. FIG. 2A and FIG. When the housing part 20 is erected, (c) is a case where the hot water container part 20 is covered with the inductor 30, (d) is a case where molten metal of the non-ferrous metal 60 to be cast is injected, and (e) is the inductor 30. When (f) is removed, (f) is a place where the hot water container 20 is also removed.

  The mold 50 (see FIGS. 2A and 2B) is composed of, for example, a lower mold 51 and an upper mold 52 of a sand mold. When the upper mold 52 is placed on the lower mold 51, a casting is formed inside the mold. A cavity 55 that defines the shape is enclosed. The upper mold 52 is formed with an injection port 54 communicating with the cavity 55, and at a place where a hot water is necessary (usually part of the upper wall of the cavity 55), the tubular hot water container 20. The hot water container 20 is erected in a state in which the hollow of this is communicated with the cavity 55. In order to make the hot water storage part standing part 53 thinner than the other part of the upper mold 52, it is preferable to reinforce it with a steel wire or a fireproof nonwoven fabric (see, for example, Patent Document 2). A known non-metallic refractory material such as shell mold sand can be used as the mold material (see, for example, Patent Documents 1 and 2). The weight of the casting determined by the size of the cavity 55 is 1 to 200 kg, but there are others, and a large one such as 500 to 1000 kg is not rare.

When the mold 50 is ready, the inductor 30 is set (see FIG. 2C). The inductor 30 is disposed on the outer peripheral side of the tubular feeder housing portion 20 so as to be covered from above. Further, a high-frequency output water-cooled cable 41 is connected to both energization ends of the high-frequency coil 33 of the inductor 30 so that high-frequency power can be supplied from the high-frequency power source 42.
And (refer FIG.2 (d)), if the preparation for casting is completed, ie, if the molten metal of the nonferrous metal 60 to be cast will be prepared, it will be poured into the cavity 55 from the inlet 54, and the electric power feeding system 40 will be operated.
As a result, the non-ferrous metal 60 to be cast, that is, the molten metal of the hot metal, enters the hollow space of the cylindrical hot water container 20, and the high frequency coil 33 inductively heats the mother cylinder 21 with the high frequency current, and the heat is transferred. The heat is transferred to the molten metal in the hollow, that is, the non-ferrous metal to be cast 60 through the heat adjustment layer 22.

  The non-ferrous metal 60 to be cast is a non-ferrous metal having a small volume resistivity at the time of melting and is not suitable for direct induction heating, but is efficiently heated by heat conduction from the mother cylinder 21. The material and thickness of the mother cylinder 21 and the material and thickness of the heat transfer adjustment layer 22 are selected in advance according to the molten metal temperature (slightly higher than the melting point) of the non-ferrous metal 60 to be cast so that the heat transfer is appropriately performed. Therefore, even if the non-ferrous metal 60 to be cast in the cavity 55 is gradually solidified, the non-ferrous metal 60 to be cast in the hollow of the tubular feeder housing portion 20 maintains the molten state, and the cast of the cavity 55 is cast. When the non-ferrous metal 60 shrinks as it solidifies, a hot water supply that compensates for it is supplied to the cavity 55 from the hot water storage portion 20.

When solidification of the non-ferrous metal 60 to be cast progresses and there is no need to supply hot water, the inductor 30 is extracted and removed (see FIG. 2 (e)) and further cooled. After solidifying sufficiently, the hot-water container 20 is removed and removed while taking care not to damage it as much as possible (see FIG. 2 (f)). Unnecessary protrusions, which are the remains of hot water and injection paths, are cut and removed.
The removed inductor 30 is reused as a matter of course, but the feeder housing part 20 is also reused as it is if it is not damaged, and if the heat insulating material 32 is partially missing, only that repair coating is applied. If the heat insulating material 32 is totally damaged, the heat insulating material 32 is scraped off, and then the heat insulating material 32 is applied over the entire inner peripheral surface of the coil support member 31.

  In this way, casting with little shrinkage or no shrinkage is performed, but induction heating to maintain the molten metal in a molten state is also a combination of indirect heating using heat transfer and open control. As described above, what is appropriately performed on the non-ferrous metal 60 to be cast is performed.

  In such a case, even if the high-frequency power supply to the high-frequency coil 33 is open control, if the temperature of the mother cylinder 21 exceeds the magnetic transformation point, the amount of heat generated by the mother cylinder 21 decreases rapidly, and the temperature of the mother cylinder 21 When the temperature falls below the magnetic transformation point, the amount of heat generated in the mother cylinder 21 recovers quickly, so that the temperature of the mother cylinder 21 is kept substantially at the magnetic transformation point. A heat flow that is substantially proportional to the temperature drop in the thickness direction in the heat transfer adjusting layer 22 is transmitted from the mother cylinder 21 to the feeder, and this is balanced with the amount of heat that escapes from the feeder to the cavity 55 and the like. Maintained at melting temperature. Moreover, since the mother cylinder 21 is a ferromagnetic metal suitable for induction heating, the high-frequency power source 42 may have a maximum output of about 5 kW. Incidentally, the conventional direct induction heating of aluminum requires a power source of about 15 kW.

  The configuration of another embodiment of the feeder for casting nonferrous metal according to the present invention will be described with reference to the drawings. 3A and 3B are perspective views schematically showing a plurality of mounting states of the non-ferrous metal casting feeder 10 to the mold 50, where FIG. 3A is a parallel connection type, and FIG. Indicates a series connection type.

  It is necessary to provide hot water feeders at a plurality of locations such as when the mold 50 is large (in the illustrated example, four locations). Inductors 30 must be externally fitted to 20 and each inductor 30 must be energized with high frequency. In addition, since the degree of cooling of the feeder is different depending on the installation location, the temperature management of the feeder, that is, high-frequency energization control must be performed independently. Therefore, in the conventional direct induction heating method, the number of the feeders 20 is not limited to the number of inductors 30 but also the power feeding system 40 and the radiation thermometer are arranged in parallel, and must be connected in parallel and controlled independently. There wasn't.

On the other hand, if the feeder 10 for non-ferrous metal casting of the present invention is used, the power supply system 40 is not limited to a small size due to indirect induction heating using heat transfer, and it can be selected as a parallel connection type or a series connection type. Can be used, so the usability is expanded.
That is, when the parallel connection type is selected (see FIG. 3A), the power feeding system 40 is connected to each inductor 30 one by one. This type is suitable when working only with the small power supply system 40. Even in this case, since it is open control, a radiation thermometer is not required.

Further, when the series connection type is selected (see FIG. 3B), the inductors 30 are connected in a single circuit and connected together to one power supply system 40. This type is suitable when working with a large power supply system 40. Also in this case, since open control is performed, a radiation thermometer is not required, and the same current is applied to any inductor 30, but the feeder housing portion where the temperature of the mother cylinder exceeds the magnetic transformation point. In 20, the main cylinder inductance is suddenly reduced, and as a result, the coil inductance and the voltage across the coil are suddenly reduced. As a result, the master cylinder temperature is maintained in the vicinity of the magnetic transformation point. Since the heat flow to the molten metal at each of the 20 and the temperature drop between the molten metal in the master tube is constant, the molten metal temperature is kept almost constant, and any hot water is appropriate as with the parallel connection type and independent control type. Maintain a molten state.
Although illustration is omitted, the parallel connection type and the series connection type can be mixed.

  The configuration of another embodiment of the feeder for casting nonferrous metal according to the present invention will be described with reference to the drawings. FIG. 4 is a perspective view schematically showing a plurality of mounting states of the hot metal apparatus 10 for casting non-ferrous metal to the mold 50.

This non-ferrous metal casting feeder 10 is obtained by dividing each feeder assembly 20 into four composite cylinders 23. That is, a plurality of the composite cylinders 23 are arranged in a densely packed manner in the hot water storage unit 20 at one location of the hot water storage unit 20.
The inductor 30 (only the high-frequency coil 33 shown in the figure) is wound in a form that comprehensively surrounds the four composite cylinders 23 for each feeder housing portion 20.
The connection of the inductor 30 is illustrated as a series connection type, but may be a parallel connection type or a combination thereof.

In this case, the hot water storage unit 20 is configured by arranging a plurality of composite cylinders 23 per one hot water storage unit 20, and the cross-sectional area of the hot water supply relating to various composite cylinders can be reduced. In casting or the like that requires a large feeder cross-sectional area, cutting of the feeder portion after solidification can be efficiently performed by sequentially removing the feeder portion having a small diameter.
Moreover, since the induction heating of the hot-water container 23 is performed by the high-frequency coil 33 (inductor) wound in a form that comprehensively surrounds a plurality of the hot-water containers 23, the composite cylinder 23 is in spite of the plurality. In addition, since the inductor 30 and the power supply system 40 are only one set, the cost increase is small.

  The structure of another embodiment of the feeder for casting nonferrous metal according to the present invention will be described with reference to the drawings. FIG. 5 is a vertical cross-sectional view schematically showing a plurality of mounting states of the hot metal apparatus 10 for casting non-ferrous metal to the mold 50.

In this non-ferrous metal casting feeder 10, the inductor 30 is shorter than the feeder housing 20, and the coil position adjustment spacer 70 is pushed by the coil 30 before the inductor 30 is fitted into the feeder housing 20. The hot water storage part 20 is fitted. Thereby, a partial section over the lower end of the hot water container 20 becomes a non-heating target section, and the inductor 30 is installed in such a vertical position.
Further, if the number of coil position adjusting spacers 70, that is, the number of stacked stages is increased or decreased, the vertical positioning of the inductor 30 can be varied, so that the section length of the non-heating target section can be adjusted.

A feeder 10 for casting a nonferrous metal according to the present invention was made as a prototype, and an aluminum cast product was produced under the following conditions.
Material name: AC4A (specific gravity 2.7 g / cm ³ )
Product weight: 500kg
Feeding hotspot: Melting point provided with five hot water containing parts 20 composed of four composite cylinders 23: 595 ° C. (liquidus 595 ° C., solidus 560 ° C.)
Hot water weight: 45kg
Outer diameter of feeder: φ51mm
Heat transfer adjustment layer thickness: 20mm
Tube height: 400 mm (100 mm inside mold, 300 mm outside mold)
Hot water closing amount: 200 mm (high height 350 mm immediately after pouring, 150 mm after solidification)
Metal cylinder: Carbon steel pipe (magnetic transformation point 780 ° C)
High-frequency power supply: 5 kW / feeding water frequency: 20 kHz
Input power: 5 kW when temperature rises 1 kW after transformation
Coagulation time: 120 minutes

In contrast, the main differences between the conventional methods are as follows.
Presser diameter: φ90mm (average)
Number of hot water: 20 places Hot water height: Approximately 450mm (including the hot water after pouring)
Hot water weight: 150kg
When these are compared, the amount of hot water is reduced to 1/3 or less from 150 kg to 45 kg.

About one embodiment of the present invention, it shows the structure of a feeder for casting non-ferrous metal, (a) is a perspective view of the overall appearance, (b) is a plan view of the fitting between the feeder housing portion and the inductor, (C) is the AA cross-sectional arrow figure, (d) is a cross-sectional view of the coil wire of a high frequency coil. The usage aspect of the hot water feeder for non-ferrous metal casting is shown, (a) is an external perspective view of a mold or the like, and (b) to (f) are all longitudinal sectional views of the mold or the like. About other embodiment of this invention, (a), (b) is a perspective view which shows typically the mounting state of the hot-water supply apparatus for non-ferrous metal casting to a casting_mold | template. It is a perspective view which shows typically the mounting state of the hot water apparatus for nonferrous metal casting to a casting_mold | template about other embodiment of this invention. It is a longitudinal cross-sectional view which shows typically the mounting state of the hot water apparatus for non-ferrous metal casting to the casting_mold | template about other embodiment of this invention.

Explanation of symbols

10: Non-ferrous metal casting feeder
20 ... cylindrical hot water container (composite cylinder),
21 ... Mother cylinder (made of ferromagnetic metal), 22 ... Heat transfer adjustment layer (made of non-metallic refractory material),
30 ... Inductor (Master tube induction heating mechanism, molten metal heating mechanism),
31 ... Coil supporting member, 32 ... Insulating material,
33 ... high frequency coil (heat resistant wire), 34 ... copper fine wire, 35 ... heat resistant coating,
40 ... Power feeding system (mother cylinder induction heating mechanism, molten metal heating mechanism),
41 ... High frequency output water cooling cable, 42 ... High frequency power supply, 43 ... Cooling water circulation device,
50 ... mold,
51 ... Lower mold, 52 ... Upper mold, 53 ... Elevated hot water storage section standing part, 54 ... Inlet, 55 ... Cavity,
60 ... Casted non-ferrous metal

Claims (9)

A cylindrical feeder containing a molten metal of a cast metal that is erected in communication with the mold and freely accommodates the molten metal surface, and a molten metal heating mechanism for inputting heat into the molten metal in the feeder containing part. In the non-ferrous metal casting feeder, the feeder housing portion is provided with a composite cylinder having a non-metallic refractory heat transfer adjustment layer provided on the inner peripheral surface of a ferromagnetic metal mother cylinder. And the molten metal heating mechanism is provided on the outer peripheral side of the composite cylinder, and includes an inductor for induction heating the mother cylinder and a power feeding system for applying high-frequency current to the inductor. Tona is, the heat transfer adjustment layer, non-ferrous, wherein the temperature drop in which is set the material and thickness such that 50 to 250 ° C., it in the direction of heat transfer through the layer Metal feeder for metal casting. The hot water feeder for non-ferrous metal casting according to claim 1 , wherein the heat transfer adjusting layer has a thickness of 2 to 20 mm. The cooling means for the inductor is cooling or blowing cooling under a configuration in which a heat insulating layer is interposed between the inductor and the composite cylinder to insulate from the composite cylinder. The hot water feeder for non-ferrous metal casting described in claim 1 or solstice . Wherein the feeder head accommodating portion, the feeder housing portion one place, according to the plurality of the composite cylinder is bristled deployed in dense form, any of claims 1 to 3, characterized in that A non-ferrous metal casting feeder. The hot water feeder for non-ferrous metal casting according to claim 4 , wherein the inductor is wound in a form that comprehensively surrounds the plurality of composite cylinders. A cylindrical feeder containing a molten metal of a cast metal that is erected in communication with the mold and freely accommodates the molten metal surface, and a molten metal heating mechanism for inputting heat into the molten metal in the feeder containing part. In the non-ferrous metal casting feeder, the feeder housing portion is provided with a composite cylinder having a non-metallic refractory heat transfer adjustment layer provided on the inner peripheral surface of a ferromagnetic metal mother cylinder. And the molten metal heating mechanism is provided on the outer peripheral side of the composite cylinder, and includes an inductor for induction heating the mother cylinder and a power feeding system for applying high-frequency current to the inductor. Tona is, the heat transfer to the thickness of the heat control layer was 2 to 20 mm, nonferrous metal casting riser and wherein the. A cylindrical feeder containing a molten metal of a cast metal that is erected in communication with the mold and freely accommodates the molten metal surface, and a molten metal heating mechanism for inputting heat into the molten metal in the feeder containing part. In the non-ferrous metal casting feeder, the feeder housing portion is provided with a composite cylinder having a non-metallic refractory heat transfer adjustment layer provided on the inner peripheral surface of a ferromagnetic metal mother cylinder. And the molten metal heating mechanism is provided on the outer peripheral side of the composite cylinder, and includes an inductor for induction heating the mother cylinder and a power feeding system for applying high-frequency current to the inductor. Tona is, the cooling means of the inductor is a cooling or blast cooling under construction that is thermally insulated from the composite tubular body by interposing an insulating layer between the inductor the composite cylinder, A non-ferrous metal casting feeder. A cylindrical feeder containing a molten metal of a cast metal that is erected in communication with the mold and freely accommodates the molten metal surface, and a molten metal heating mechanism for inputting heat into the molten metal in the feeder containing part. In the non-ferrous metal casting feeder, the feeder housing portion is provided with a composite cylinder having a non-metallic refractory heat transfer adjustment layer provided on the inner peripheral surface of a ferromagnetic metal mother cylinder. And the molten metal heating mechanism is provided on the outer peripheral side of the composite cylinder, and includes an inductor for induction heating the mother cylinder and a power feeding system for applying high-frequency current to the inductor. Tona is, the feeder housing portion, for feeder housing portion one position, the plurality of composite cylinder is bristled deployed in dense form, nonferrous metal casting riser and wherein the. The non-ferrous metal casting feeder according to claim 8 , wherein the inductor is wound in a form that comprehensively surrounds the plurality of composite cylinders.

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