JPS6266089A - Crucible type induction furnace - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention [Technical Field to which the Invention Pertains] The present invention provides a fixed crucible arranged inside a cylindrical induction heating coil provided in a closed container, and heat treatment such as melting of metal in the crucible. After performing this, while the crucible is held in the closed container, the molten metal in the crucible is poured or injected outside through the nozzle through the opening formed at the bottom of the molten metal by means of pressure gas introduced from the outside. This article relates to a crucible-shaped induction furnace. In this type of visiting furnace, the M structure is such that the nozzle can be easily connected to or separated from the crucible when the crucible is installed in the closed container or when the crucible is replaced. In addition, it is required that the molten metal does not bleed or leak from the connection between the crucible and the noise.

[Prior art and intervening Zhao point]

Generally, as shown in FIG. 3, this type of crucible-shaped induction furnace houses a regular-shaped crucible 1 having an opening la at the bottom inside an induction heating coil 2 fixed therein, and gas is introduced into the vessel wall. The shaped crucible 1 is supported on the bottom 7C of a closed container 7 equipped with a gas introduction device 9 for introducing gas into the interior and a pressure regulating valve 10 for adjusting the pressure of the gas inside. A nozzle 5 having a nozzle hole 5a that communicates the provided opening 8 with the bottom opening 1a of the regular crucible l.
By providing a crucible support 4 for holding the metal and a nozzle hole opening/closing rod 6 for opening and closing the nozzle hole 5a from the top with the closed container 7 sealed, the metal can be heated in the atmosphere. After sealing the airtight container 7 or heat-treating the metal in a closed atmosphere of air or inert gas inside the airtight container 7, operate the nozzle hole opening/closing rod 6 to open the nozzle hole 5a and open the gas introduction device. It is known that the molten metal is poured or injected by the pressure of the gas introduced through the pipe 9.

However, in the induction furnace illustrated in Fig. 3, the shaped crucible l
The bottom opening la is simply fitted into the protrusion 5d of the head of the nozzle 5 held on the crucible support 4 via the heat insulating material 21, which protrudes from the upper end of the crucible support 4. Supported and wedged J#1b above 14
A structure 16 made of refractory material inside the closed container 7 via
When replacing the crucible, the crucible can be easily separated from the support base 4 and taken out of the closed container 7 by simply removing the wedge 14. On the other hand, when installing a new crucible 1, it is necessary to fit the bottom opening 1.3 of the crucible 1 into the projection 5d of the head of the nozzle 5 so that the vertical axis of the crucible 1 is aligned directly with the island heating coil 2. It is not easy to fix the upper edge 1b of the crucible l to the structure 1b via the wedge 14 so as to match the vertical axis, and the protrusions on the bottom m opening 1a of the crucible l and the head of the nozzle 5 are difficult to fix. This has the drawback that it is difficult to prevent the bath water in the crucible l from seeping out and leaking from the long gap in the fitting part with the crucible 5d.

On the other hand, as a nozzle connected to this type of regular crucible in order to overcome the above-mentioned drawbacks, a nozzle as illustrated in FIG. 4 is known. That is, a projection 5C is provided on the top surface of the head of the nozzle 5 which is fixed to the crucible support base 4 via the heat insulating material 21.
and supports the bottom surface of the crucible 1. The collar 5b is fitted into the hole 4a, and the support provided on the top surface of the crucible support base 4 is fitted into the hole 4a. 5b and the projection 5C, and a bonding layer 5 made of a heat-resistant adhesive is formed at the portion where the crucible 1 joins 5b and the projection 5C, thereby interconnecting the crucible 1 and the nozzle 5. I do what I do.

With the above-described structure, the gap between the joint between the bottom opening 1a of the crucible 1 and the nozzle 5 is completely filled with the joint layer 26 made of the adhesive, so that the molten metal in the crucible 1 can flow from the joint between the bottom opening 1a and the nozzle 5. There is no risk of leakage, and the connection between the crucible 1 and the nozzle 5 is made in a closed container 7.
The crucible 1 to which the nozzle 5 is connected can be inserted into the vertical through hole 4b of the crucible support 4.
By inserting the nozzle 5 as a guide, the crucible can be easily mounted on the crucible support 4, and the vertical axis of the heating coil 2 can be aligned with the vertical axis of the crucible 1, which makes the work extremely simple. In addition to this, the upper edge 1b
(Four vertical expansions due to heat of the crucible l fixed through the rust 14, the crucible is received by the crucible support 4U through the collar 5b of the nozzle 5, and the crucible is placed one place inside the heating coil 2. There is also the advantage that the retention of l is stable.

However, on the other hand, in the nozzle 51 illustrated in FIG.
b, the shape is complicated, and there is a drawback that the processing pressure and number of parts are required to reduce the number of parts by machining, and the mold for forming the parts is a considerable economic burden if the number of parts is to be reduced by machining.

[Purpose of the invention]

Does the present invention involve heat treatment in a shaped crucible? In view of the above-mentioned drawbacks of conventional crucible induction furnaces in which molten metal is poured or injected through a nozzle,
It is an object of the present invention to provide an economically advantageous crucible-shaped induction furnace in which a nozzle having a simple shape and easy to manufacture by machining or molding is connected to the regular crucible.

[Key points of the invention]

In order to achieve the above object, the present invention provides the following induction furnace l.
The nozzle hole has a predetermined nozzle hole that coincides with the central axis of the crucible, one end of which has a shape suitable for being supported by the inner surface of the bottom of the crucible or the inner circumferential surface of the bottom opening, and the other end of which is formed into a shape suitable for supporting the molten metal. The one end of the cylindrical nozzle, each formed in a shape suitable for pouring or injection, is connected to the inner surface of the bottom of the crucible or the inner peripheral surface of the bottom opening through a bonding layer made of a suitable adhesive, and The nozzle is inserted into a vertical through hole of the crucible support, the other end is exposed to the outside through the bottom opening of the closed container, and the crucible is supported on the upper surface of the crucible support through a majority of the cushioning material. By doing so, after the crucible and the nozzle are connected outside the sealed container, the nozzle is inserted into the through hole of the crucible support base, and the crucible is housed in the sealed container. .

[Embodiments of the invention]

Next, the present invention will be explained in detail based on embodiments shown in the drawings.

In the crucible-shaped induction furnace of the present invention, in which a fixed-shaped crucible is housed in a closed container and heat-treated molten metal is poured or injected through a nozzle using pressurized gas, as shown in FIG. A gas introduction device 9 for introducing gas into the wall of the crucible housing a regular crucible 1 having an opening 1a at the bottom inside an induction heating coil 2 fixed therein.
A regular-shaped crucible 1 is supported on the bottom 7c of a sealed container 7, which is equipped with a pressure control valve 1o for adjusting the pressure of the gas inside. A crucible support 4 holding a nozzle 5 having a nozzle hole 5a that communicates with the bottom opening 1a is provided, and a nozzle hole opening/closing rod 6 is provided for opening and closing the nozzle hole 5a from above while the closed container 7 is sealed. Therefore, after heat-treating the metal in the atmosphere and then sealing the closed container, or after heat-treating the metal in a closed atmosphere of air or inert gas in the closed container 7, the nozzle hole opening/closing rod can be closed. 6 to open the nozzle hole 5a and pour out or inject the molten metal through the nozzle hole 5a using the pressure gas introduced through the gas introduction device 9, which has the same structure and function. However, in the crucible type induction furnace of the present invention, one end vl'i, that is, the lower end is used for pouring molten metal or The nozzle hole 5a' is formed to be suitable for injection and coincides with the central axis of the nozzle hole 5a'. As shown in FIG. 1 or 2, the nozzle 5 is inserted into the vertical through-hole 4b of the crucible support 4, which supports the foot-shaped crucible 1 through the material, through an appropriate heat insulating material 21. The one or lower end of the nozzle 5 is inserted through the bottom opening 8 of the closed container 7 so as to be exposed to the outside, while the loose end or upper end of the nozzle 5 is inserted into the cylindrical lower part of the regular crucible as shown in FIG. fN'1 at the upper end of the opening 1a of the crucible l
o) The bottom part (c) is formed in the shape of a lattice suitable for locking, and the nozzle 5 is shaped by a bonding layer made of a heat-resistant adhesive at the upper end including the lattice-shaped part. crucible l
It is glued and held on the inner surface of the bottom. At this time, an appropriate filler 4 is applied to fill the difference in level between the shell-shaped portion of the nozzle 5 and the inner surface of the bottom of the regular crucible 1 and smooth the inner surface of the bottom of the crucible 1. There is.

Alternatively, as another embodiment, as shown in FIG.
Similarly, the nozzle 5 having an upper end formed in a shape suitable for support by the opening 1a may be adhesively held on the inner circumferential surface of the opening 1a using a bonding layer made of adhesive. In this case, there is an advantage that there is no need for a light shield as in the embodiment shown in FIG.

In either of the embodiments shown in FIG. 1 or wI2, the bottom surface of the regular crucible l is supported on the upper surface of the crucible support base 4 via a suitable cushioning material 27, so that the nozzle 5
Due to the tension between the insertion of the crucible support 4 into the through hole 4b and the installation of the crucible 1 to the support 4, stress may be generated in the joint layer at the connection between the crucible 1 and the nozzle 5. can be prevented.

The nozzle 5 described above has a cylindrical shape with simple processing on both ends, so it is extremely easy to cut it from the material by machining, and when it is actually manufactured by molding, it can also be molded. It has the advantage that a simple mold is sufficient.

Furthermore, when connecting the nozzle 5 to the regular crucible 1, it is only necessary to insert the nozzle from the upper opening into the bottom opening 1a of the crucible and connect them with adhesive. It is easy to connect or separate them, and it is also easy to install them on the support base 4. In this case, the upper edge 1
The shaped crucible 1 is held by the structure 1b inside the closed container 7 via the wedge 14.

Its axial expansion due to heat, John 27fj! : Since the crucible 1 is supported by the upper surface 4C of the crucible support 4 through
The presence of fJ26 is effective in preventing seepage and leakage of the molten metal at the connection between the crucible 1 and the nozzle 5. In this case, it is extremely important that the connecting portion between the regular shaped collar l and the nozzle 5 shown in FIGS. It's advantageous.

〔Effect of the invention〕

As explained above, the present invention arranges a shaped crucible inside a cylindrical induction heating coil provided in a closed container,
After performing heat treatment such as melting the metal in the crucible,
A crucible-shaped induction device in which, while the crucible is held in the container (vine), the molten metal in the crucible is poured or injected from an opening formed at the bottom of the crucible to the outside through a nozzle by means of pressurized gas introduced from the outside. The furnace has a predetermined nozzle hole that coincides with the central axis of the furnace, one end of which is shaped to be supported by the inner surface of the bottom of the crucible or the inner peripheral surface of the bottom opening, and the other end of which is shaped so as to be supported by the inner surface of the bottom of the crucible or the inner peripheral surface of the bottom opening. The one end of the cylindrical nozzle, each formed in a shape suitable for extraction or injection, is connected to the inner surface of the bottom of the crucible or the inner peripheral surface of the bottom opening through a bond I- made of a suitable adhesive, and Insert the nozzle into the vertical through-hole of the crucible support, let the other end peek out from the bottom opening of the closed container, and properly glue the crucible on the upper surface of the support with a sheet of material. By doing this, a nozzle having a connection part and a spout for a simple shaped crucible at both ends of a simple cylinder is connected to the shaped crucible with an adhesive outside the sealed container, and then inserted into the container. By storing the crucible, it is possible to stably hold the crucible inside the induction heating coil, and the shape of the connecting portion, together with the use of the adhesive, is not only extremely effective in preventing seepage and leakage of molten metal. Machining when cutting the nozzle is extremely easy, and when manufacturing by molding, a simple mold is sufficient, which is extremely advantageous economically.

[Brief explanation of drawings]

1 and 2 are longitudinal sectional views illustrating a method of connecting a forming crucible and a nozzle related to the crucible induction furnace of the present invention, and FIG. 3 is a crucible induction furnace including the crucible induction furnace of the present invention. FIG. 4 is a vertical cross-sectional view showing the general configuration, and FIG. 4 is a vertical cross-sectional view illustrating a method of connecting a regular crucible and a nozzle of a conventional crucible induction furnace. l...shaped crucible! &... Bottom opening of regular crucible, 2... Induction heating coil, 4... Crucible support stand, 4
b... Through hole of crucible support base, 4C... Crucible support surface, 5... Nozzle, 5a... Nozzle hole, 7... Sealed container, 7C-... Bottom of sealed container, 8... - Bottom opening of airtight container, 9... gas introduction device, 10... pressure regulating valve,... bonding layer, n... ri, john. Figure 3 Figure 4

Claims (1)

[Claims] 1) A regular crucible is placed inside a cylindrical induction heating coil provided in a closed container, and after heat treatment such as melting of metal is performed in the crucible, the crucible is held in the closed container. In a crucible-type induction furnace in which the molten metal in the crucible is poured or injected to the outside through a nozzle from an opening formed at the bottom of the crucible by means of pressurized gas introduced from the outside, It has a nozzle hole, one end is formed in a shape suitable for being supported by the inner surface of the bottom or the inner peripheral surface of the bottom opening of the regular crucible, and the other end is formed in a shape suitable for pouring or injecting the molten metal. The one end of the cylindrical nozzle is connected to the inner surface of the bottom of the crucible or the inner peripheral surface of the bottom opening through a bonding layer made of a suitable adhesive, and the nozzle is connected to the vertical through hole of the crucible support. A crucible-shaped induction furnace characterized in that the crucible is inserted so that the other end thereof is exposed to the outside through a bottom opening of the closed container, and the crucible is supported on the upper surface of the support table via a suitable cushioning material.