JP2831376B2 - Immersion burner type low pressure casting furnace - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an immersion burner type low-pressure casting furnace for melting a casting material in a furnace chamber by an immersion burner and feeding a molten metal into a mold to cast a cast product.

[Prior Art] Conventionally, a crucible type casting furnace as shown in FIG. 4 has been used for gas-fired low-pressure casting, and a crucible r in a furnace chamber is heated by a gas burner b provided at a lower portion of a furnace body to form a crucible r. Was melted and the molten metal y was fed into the mold k through Stokes s to cast a casting.

[Problems to be Solved by the Invention] In the case of the above-mentioned crucible type casting furnace, there is a problem that the molten metal y is indirectly heated via the crucible r, so that the thermal efficiency is reduced.
When the crucible r is damaged and the molten metal leaks out, the leaked molten metal may damage the furnace wall and the gas burner, and the replacement of the crucible r may be complicated.

An object of the present invention is to solve the above problems.

[Means for Solving the Problems] The immersion burner type low-pressure casting furnace of the present invention has a heating section of an immersion burner immersed in a molten metal in order to heat the molten metal in a closed furnace chamber, and the molten metal in a mold. A stirrer connected to a mold for feeding the mold and a gas supply line controlled to be open / closed to feed a pressurized gas for pressurizing molten metal into the furnace chamber in the furnace chamber, Closing and opening the air supply line to discharge the pressurized gas and the combustion gas of the immersion burner from the furnace chamber when the air supply line is closed, and to seal the furnace room when the air supply line is opened. And an exhaust pipe whose opening and closing path is controlled in synchronization with the exhaust pipe.

[Operation] When the immersion burner is ignited and the molten metal in the furnace chamber is heated, the air supply line connected to the furnace chamber is closed to stop the supply of the pressurized gas into the furnace chamber, and is connected to the furnace chamber. The pressurized gas and the combustion gas of the immersion burner are exhausted from the furnace chamber by opening the exhaust pipe, and the feed pipe is opened and pressurized into the furnace chamber when the molten metal is fed into the mold. A gas is supplied, and the exhaust pipe is closed to close the furnace chamber, and the open and closed paths of the air supply pipe and the closed and open paths of the exhaust pipe are alternately and synchronously advanced. I do.

[Effects of the Invention] Since the present invention is configured as described above, the supply and exhaust of air into and out of the furnace chamber, the supply of molten metal to the mold, and the stop of the supply of the molten metal are synchronously and accurately performed. This has the effect that the casting can be efficiently performed and the casting can be efficiently cast, and at the same time, the melt leakage can be eliminated.

In addition, since the molten metal is directly heated by the immersion burner immersed in the molten metal, the thermal efficiency when heating the molten metal can be improved, and the combustion gas flowing into the furnace chamber by using the immersion burner can be discharged into and out of the furnace chamber. Discharge processing can be accurately performed in synchronization with supply and exhaust of pressurized gas.

Next, an embodiment of the present invention will be described with reference to FIGS.

In a immersion burner type low-pressure casting furnace applied to heat a casting material by an immersion burner and feed a molten metal into a mold to cast a casting, a molten metal 3 in which a casting material is melted is placed in a furnace body 1. A furnace chamber 2 for accommodating the molten metal 3 is formed in a closed shape, and is connected to a mold 4 near the left end of the upper wall 1a of the furnace body 1 in order to feed the molten metal 3 into a casting mold 4. Then, the stalk 5 charged into the furnace chamber 2 is attached vertically, and the lower part of the stalk 5 is immersed in the molten metal 3.

An immersion burner 6 attached downward to the center of the upper wall 1a of the furnace body 1 has a furnace chamber 2 for directly heating the molten metal 3.
A heating unit 6a is provided therein and is immersed in the molten metal 3. A heating portion 6a of the immersion burner 6 is formed of a ceramic material into a bottomed cylindrical shape and is immersed in the molten metal 3;
A cylindrical inner cylinder 8 inserted concentrically into the outer cylinder 7
A combustion gas passage 9 for flowing combustion gas is formed between the outer cylinder 7 and the inner cylinder 8, and the combustion gas is supplied to the upper part of the outer cylinder 7 from within the combustion gas passage 9. A discharge hole 10 for discharging into the furnace chamber 2 is provided. A fuel supply pipe 11 connected to a gas fuel supply pipe 12 having an on-off valve 13 is inserted into the inner cylinder 8, and an on-off valve is connected to an air supply port 16 communicated with the upper end of the inner cylinder 8. Air supply line with 15
14 is connected, and combustion air is supplied to the end of the fuel supply pipe 11 through the inner cylinder 8.

An air supply opening 20 opened near the right end of the upper wall 1a of the furnace body 1 in the drawing has an air supply line 17 provided with an on-off valve 18 and a pressure regulating valve 19.
Is connected to feed a pressurized gas for pressurizing the molten metal into the furnace chamber 2, and has an exhaust pipe 21 provided with an on-off valve 22 at an exhaust port 23 opened to the right of the air supply port 20. It is connected to discharge pressurized gas and exhaust gas from inside the furnace chamber 2,
Is pressurized by the pressurized gas sent into the furnace chamber 2 through the air supply line 17 and is fed into the mold 4 through the stalk 5.

The on-off valve 18 of the supply line 17, the on-off valve 22 of the exhaust line 21, the on-off valve 13 of the gas fuel supply line 12, and the on-off valve 15 of the air supply line 14 are temperature sensors for detecting the temperature of the molten metal 3, And mold 4
The operation is controlled synchronously based on the output signal of a timer that sets the molten metal feeding time, and each of the on-off valves 18, 22, 13, 15 closes the exhaust line 21 when the air supply line 17 is opened. And the fuel gas supply line 12 and the air supply line 14 are closed respectively, while the exhaust line 21 is closed when the air supply line 17 is closed.
Is open and the gas fuel supply line 12 and the air supply line 14
Are alternately switched so that each of them is opened.

Then, while the required amount of molten metal 3 raised to the prescribed temperature is fed into the mold 4, pressurized gas is fed into the furnace chamber 2 in which the air supply pipe 17 is opened, and The supply of gaseous fuel and combustion air is stopped, the immersion burner 6 is extinguished, the furnace chamber 2 is closed, and the molten metal 3 is pressurized by the pressurized gas, while the molten metal 3 is supplied to the mold 4. Is completed, the air supply line 17 is closed, the supply of pressurized gas into the furnace chamber 2 is stopped, gas fuel and combustion air are supplied to the immersion burner 6, the immersion burner 6 is ignited, and the furnace The pressurized gas and the combustion gas are discharged from the chamber 2 through the exhaust pipe 21 and the molten metal 3
Is heated by the immersion burner 6.

Next, the operation and effect of the embodiment having the above configuration will be described.

In the present embodiment, a heating section 6a of an immersion burner 6 immersed in the molten metal 3 to heat the molten metal 3 in the closed furnace chamber 2;
In order to feed the molten metal 3 into the mold 4 and a Stoke 5 connected to the mold 4, and to feed a pressurized gas for pressurizing the molten metal 3 into the furnace chamber 2 into the furnace chamber 2. A gas supply line 17 whose opening and closing path is controlled, and the pressurized gas and the combustion gas of the immersion burner 6 are discharged from the furnace chamber 2 when the gas supply line 17 is closed, and the furnace chamber is opened when the gas supply line 17 is opened. 2 is connected to an exhaust line 21 whose opening and closing path is controlled in synchronism with the closing and opening of the air supply line 17 in order to seal the inside of the gas supply line 17. Further, the gas fuel supply line 12 connected to the immersion burner 6 and the air The supply line 14 is configured to open and close in synchronization with the closing and opening of the air supply line 17.

Therefore, the supply and exhaust of air into and out of the furnace chamber 2, the supply and stop of the supply of the molten metal 3 to the mold 4, and the extinguishing and ignition of the immersion burner 6 are synchronously and accurately performed. This has the effect of efficiently casting a cast product and eliminating molten metal leakage and troubles associated with molten metal leakage.

Further, since the molten metal 3 is directly heated by the immersion burner 6 immersed in the molten metal 3, the thermal efficiency when heating the molten metal 3 can be improved, and the combustion flowing out into the furnace chamber 2 by using the immersion burner 6. The gas can be discharged properly in synchronization with the supply and exhaust of the pressurized gas into and out of the furnace chamber 2.

[Brief description of the drawings]

1 to 3 show one embodiment of the present invention.
The figure is a vertical sectional view of a immersion burner type low pressure casting furnace showing a molten metal pressurized state, FIG. 2 is a vertical sectional view showing the same molten metal heating state, FIG. 3 is a time chart, and FIG. It is a longitudinal cross-sectional view. 2 furnace chamber 3 molten metal 4 mold 6 immersion burner 17 air supply line 21 exhaust line

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shigeo Takahashi 19-18 Sakuradacho, Atsuta-ku, Nagoya-shi, Aichi Toho Gas Co., Ltd. (56) References JP-A-1-300104 (JP, A) JP-A 1-287228 (JP, A) (58) Field surveyed (Int. Cl. ⁶ , DB name) B22D 18/04 F27B 3/00-3/28

Claims (1)

(57) [Claims] In a closed furnace chamber, a heating section of an immersion burner immersed in the molten metal to heat the molten metal, and a stalk connected to the mold to feed the molten metal into the mold. And a gas supply line controlled to be opened and closed to feed a pressurized gas for pressurizing the molten metal into the furnace chamber, and the pressurized gas from the furnace chamber when the gas supply line is closed. And an exhaust line controlled to open and close in synchronization with the closing and opening of the air supply line to discharge gas and combustion gas of the immersion burner and to seal the furnace chamber when the air supply line is opened. An immersion burner type low pressure casting furnace characterized by being connected.