JP2003117649A - Method for supplying fixed quantity of molten metal and pump for supplying molten metal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To supply a fixed quantity of molten metal, typically a magnesium having high combustibility without causing error as much as possible, into a mold, etc., and without exposing the metal to the atmosphere. SOLUTION: A closed vessel 2 forming a pressurized chamber 3 in a furnace 1 is disposed and the molten metal in the furnace 1 is taken into the pressurized chamber 3 by operating a suction valve 7 and opening a taking-in hole 4. Successively, the taking-in hole 4 is closed, and inert gas is poured into the pressurized chamber 3. In this way, when the pressure of the inert gas acting on the pressurized chamber 3 reaches to a setting value, an opening part at one end of an exhaust flow passage 5 is opened for a fixed time by operating an exhausting valve 8 while keeping the taking-in hole 4 closed. Then, while holding the pressure of the inert gas acting on the pressurized chamber 3 constant, the molten metal is pushed out into the exhaust flow passage 5 from the pressurized chamber 3 at the held constant pressure. Thus, the molten metal of the fixed quantity in the pressurized chamber 5 can be supplied into a molten metal supplying object D, such as the mold, through the exhaust flow passage 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for quantitatively supplying a molten metal, and in particular, a highly combustible molten magnesium is quantitatively compared with a mold or other molds with a minimum error. The present invention relates to a supply method and device.

[0002]

2. Description of the Related Art Generally, when metals are dissolved in the atmosphere, they are more or less contaminated by acidity, hydrogen, or water vapor,
The oxides and the like float as a film on the surface of the molten metal. Therefore, when the molten metal in the melting furnace is cast using a ladle, it is necessary to remove oxides floating on the molten metal surface to prevent the oxides from mixing. However, this kind of work is performed by human beings in a poor environment and is physically dangerous, and moreover, unless the divided molten metal is poured quickly, many oxides are generated on the surface. Not only will it burn, but magnesium, which has high flammability, will catch fire before being cast. For this reason, many technologies have been proposed and many have been put into practical use, in which the molten metal in the furnace can be cast without being exposed to the atmosphere.

For example, one of them is Japanese Patent Laid-Open No. 18736/1992.
No. 6 pump is known. The outline is shown in FIG. 13 and explained. R is a room having a predetermined volume, and this room is for supplying a fixed amount chamber R ₁ for storing a fixed amount of molten metal and an inert gas to the upper part thereof. is divided functions the compression chamber R _2, quantitative chamber introduction passage extends toward the furnace bottom from its upper end to the R ₁ E _i addition, the discharge path E _o that extends out of the furnace from the lower end is formed. Then, according to this pump, the molten metal in the furnace is taken into the metering chamber R ₁ through the introduction path E _i , and then the inert gas is injected into the pressurizing chamber R _{2 so} that the molten metal surface reaches the upper end of the metering chamber R ₁ . By lowering the gas pressure in the pressurizing chamber R ₂ and increasing the gas pressure in the pressurizing chamber R ₂ , all of the metal melt in the metering chamber R ₁ can be quantitatively supplied to an external device through the discharge passage E _o . However, in the pump as described above, when the molten metal level in the furnace is high and a large amount of molten metal flows into the pressurizing chamber, not only it takes time to lower the molten metal level to the upper end of the metering chamber R ₁ , but also In the process, the metal melt in the metering chamber R ₁ is discharged into the discharge path E _o.
There is a risk that it will flow out to the outside through, and since it takes time to raise the pressure chamber R ₂ to a predetermined pressure,
There is a problem that a fixed amount of molten metal cannot be supplied to the outside in a short time.

On the other hand, in Japanese Unexamined Patent Publication No. 1-96856, FIG.
Pumps such as those shown in are proposed. This pump has a bottom chamber B immersed in molten metal in the furnace, and an inlet E _i opened and closed by a suction valve V ₁ and a discharge port opened and closed by a discharge valve mechanism V ₂ in the bottom chamber B. E _o and are formed.
Further, a cylinder tube S rising upward is connected to the bottom chamber B, and an intake valve V ₁ and a discharge valve mechanism V _{2 are provided} inside thereof.
Is provided with a piston P that moves up and down in conjunction with. And
This pump takes in an appropriate amount of molten metal in the furnace from the inlet E _i to the bottom chamber B by raising the piston P, then closes the inlet E _i , and then lowers the piston P while opening the outlet E _o. Thus, the molten metal in the bottom chamber B can be supplied to the external device. However, since the metal oxide attached to the inner surface of the cylinder tube S hinders the movement of the piston P, it is difficult to maintain the device performance for a long period of time, and the supply amount of the molten metal depends on the movement operation amount of the piston P. Since it changes, it is extremely difficult to quantitatively supply the molten metal.

Therefore, Japanese Patent Laid-Open No. 3-264155 proposes a pump as shown in FIG. This pump mainly comprises a tank T capable of filling gas,
A pipe K for forming a molten metal suction portion E _i in the tank T
₁ and a pipe K ₂ forming a molten metal extraction part E _o are connected to each other, and a suction part E _i and an extraction part E _o are respectively inserted in these pipes.
It is configured by arranging check valves F ₁ and F ₂ of a float type for opening and closing. Further, according to this pump, by supplying and discharging the inert gas to and from the tank T, the suction part E _i and the extraction part E _o are alternately opened and closed to supply the molten metal to the outside of the furnace, and further, the molten metal comes into contact with the molten metal. Since the movable parts are only the check valves F ₁ and F ₂ , the durability of the device can be improved.

[0006]

However, according to the pump as shown in FIG. 15, it takes time to change the inside of the tank from the depressurized state in which the suction portion opens to the pressurized state in which the takeout portion opens. It is difficult to quantitatively supply the molten metal to an external device because the opening and closing time of the take-out part greatly changes depending on the viscosity of the molten metal caused by the type of metal used and the temperature. The temperature of the melt must be controlled very accurately.

The present invention has been made in view of the above circumstances, and an object thereof is to prevent a metal melt such as magnesium having high combustibility from being exposed to the atmosphere without causing an error in a mold or the like. It is to be able to supply a fixed amount.

[0008]

In order to achieve the above object, the present invention takes in molten metal in a furnace into a pressurizing chamber whose pressure can be adjusted, closes the intake port, and then operates a discharge valve. A method of supplying the molten metal taken into the pressurizing chamber to a hot water supply object such as a mold through opening the discharge flow path that can be opened and closed by means of opening the discharge flow path. While the inlet is closed in advance, an inert gas is injected into the pressure chamber to pressurize the pressure chamber, and after the pressure reaches a set value, the discharge valve is operated to keep the discharge flow path constant. Provided is a method for quantitatively supplying a molten metal, which is characterized by opening for a period of time.

Further, in the method according to the second aspect, the metal melt in the furnace is taken into a pressurizing chamber whose pressure can be adjusted through an intake port opened in the metal melt stored in the furnace, The inlet was closed by operating the suction valve, and then the pressurized chamber was pressurized by injecting an inert gas into the pressurized chamber, and after the pressure reached a set value, the inlet was closed. While maintaining the pressure of the inert gas acting on the pressure chamber constant, the discharge flow path connected to the pressure chamber is opened for a certain period of time by operating the discharge valve, so that the discharge flow from the pressure chamber is increased. It is characterized by controlling the flow rate of the molten metal sent to a hot water supply target such as a mold through a passage.

On the other hand, according to a third aspect of the present invention, a heat-resistant closed container forming a pressure-adjustable pressurizing chamber having an inlet for taking in the molten metal in the furnace, and the inlet are provided. A suction valve that opens and closes, a discharge flow path for guiding the molten metal taken into the pressurizing chamber to a hot water supply target such as a mold, a discharge valve that opens and closes the discharge flow path, the intake port and the discharge flow path. And an operating system for operating the intake valve and the exhaust valve to open alternately, and before injecting an inert gas into the pressurizing chamber before opening the exhaust flow path by operating the exhaust valve by this operating system, A pressure adjusting means for controlling pressurization of the pressurizing chamber, and the operating system is configured to open the discharge passage for a certain period of time after the pressure of the inert gas acting on the pressurizing chamber reaches a set value. Provided is a molten metal supply pump characterized in that a control unit for operating a discharge valve is provided. Is shall.

Further, in the above-mentioned pump, a porous nozzle plate is provided at the tip of the discharge passage to prevent the molten metal from leaking from the tip of the discharge passage when the discharge valve is closed. And

Furthermore, the discharge valve is a rod-shaped heat-resistant seal plate having a flexible flange-like shape that is provided so as to be able to move up and down on one end opening of the discharge flow path that opens at the bottom of the pressurizing chamber. Is fixed, and the upper part of the closed container is projected onto the molten metal surface of the molten metal stored in the furnace as a guide cylinder for passing the discharge valve into the pressurizing chamber, and the heat-resistant seal plate is provided at the upper end opening edge thereof. It is characterized in that the peripheral portion is fastened with airtightness.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, application examples of the present invention will be described in detail with reference to the drawings. First, the outline of the present invention will be described with reference to FIG. Reference numeral 1 is a furnace for melting a metal such as magnesium, and a heating source (not shown) such as a burner is attached to the outer peripheral portion of the furnace. Reference numeral 2 is a heat-resistant closed container that is immersed in the molten metal in the furnace, and the inside of which forms a pressurizing chamber 3 whose pressure can be adjusted. The pressurizing chamber 3 is provided with an intake port 4 that opens into the molten metal in the furnace 1, and one end of an exhaust flow path 5 is connected to the bottom of the intake port 4. The discharge flow path 5 projects upward from the bottom of the pressurizing chamber 3 through the molten metal in the furnace 1 and extends obliquely upward from the upper part of the furnace 1, and its tip is stored in the furnace 1. Surface L of molten metal
It opens downward at a higher position. The discharge flow path 5
A nozzle plate 6 which will be described later is provided at the tip of the nozzle, and the molten metal is discharged from the nozzle plate 6 to a hot water supply target D such as a mold.

On the other hand, 7 is a suction valve that opens and closes the intake port, and 8 is a discharge valve that opens and closes the discharge flow path. The suction valve 7 and the discharge valve 8 are rod-shaped valve bodies having a predetermined length. It is said that
Of these, the discharge valve 8 is provided so as to be able to move up and down on one end of the discharge flow path that is opened at the bottom of the pressure chamber 3 and forms a discharge port 9 for discharging the molten metal in the pressure chamber to the outside. To be It should be noted that the guide cylinder 1 through which the discharge valve 8 is passed over the closed container 2.
0 is provided, and the lower end of the guide cylinder 10 is continuous with the pressurizing chamber 3 and the upper part thereof is projected onto the molten metal surface L of the molten metal stored in the furnace 1. In particular, the upper end opening of the guide tube 10 is sealed by a heat resistant seal plate 11 described later,
Thus, the airtightness of the pressurizing chamber 3 can be maintained.

Reference numeral 12 is an operating system for operating the intake valve and the exhaust valve. This operating system 12 is composed of an air pressure circuit using an air compressor 13 as a power source in this embodiment, and the intake valve 7 and the exhaust valve are provided. Air cylinders 14 and 15 are connected to 8 as actuators driven by compressed air supplied from an air compressor 13, respectively. Solenoid valves 16 and 17 are interposed in the air supply systems for supplying compressed air as working fluid from the air compressor 13 to the air cylinders 14 and 15, respectively, and the solenoid valves 16 and 17 are not shown. The control unit is connected to the control circuit to control the driving of the air cylinders 14 and 15.

Here, the intake port 4 and the discharge flow path 5 are alternately opened by the operation of the intake valve 7 and the discharge valve 8 by the operation system 12, but they are not shown in the control circuit constituting the above-mentioned control section. A built-in timer is incorporated, and the opening time of the intake port 4 and the discharge flow path 5 can be adjusted by the setting thereof. That is, the suction valve 7 is first operated while the discharge flow path 5 is closed by the time setting by the timer to open the intake port 4 for a certain time, whereby the molten metal in the furnace 1 is taken into the pressurizing chamber 3, After closing the intake port 4, the discharge valve 8 is operated with the intake port 4 closed to open one end of the discharge flow path 5 (discharge port 9).
Is controlled to open for a certain period of time. Further, according to the present invention, when the discharge flow path 5 is opened, the molten metal taken into the pressurizing chamber 3 is pushed out by the pressure of the inert gas which has acted in advance on the molten metal surface, which is discharged. It is designed to be quantitatively supplied to the hot water supply target D through.

Reference numeral 18 denotes a gas supply system for injecting an inert gas necessary for pushing out the molten metal into the pressurizing chamber. The gas supply system 18 controls the pressure of the inert gas acting on the pressurizing chamber 3. A pressure adjusting means for controlling the pressurization so as to keep the pressure constant is configured. In this example, the gas supply system 18 uses a gas cylinder 19 filled with an inert gas as a supply source, and connects the gas cylinder 19 and the upper side surface of the guide cylinder 10 to each other.
0, a pressure control valve 21 (regulator with relief), a pressure gauge 22, a solenoid valve 23, etc. are interposed. Further, according to the gas supply system 18 which constitutes the pressure adjusting means, the inert gas in the gas cylinder 19 is supplied from the gas pipe 20 through the guide cylinder 10 to the molten metal surface in the pressurizing chamber 3 to thereby pressurize the gas. When the pressure of the inert gas acting on the chamber 3 reaches a set value, the pressure control valve 21 releases the inert gas having a pressure equal to or higher than the set pressure into the atmosphere, so that the pressure of the inert gas acting on the pressurizing chamber 3 is increased. Can be kept constant. In particular, the pressure of the inert gas acting on the pressurizing chamber 3 can be adjusted by setting the operating pressure of the pressure control valve 21, but the pressure gauge 22 and the solenoid valve 23 are provided on the secondary side of the pressure control valve 21.
In addition, a pressure switch (not shown) is provided, and when the pressure switch detects that the pressure of the inert gas acting on the pressurizing chamber 3 has reached a set value, the detection signal outputs a detection signal. The discharge flow path 5 can be opened by operating the discharge valve 8.

Further, the gas pipe 20 has a branch pipe 24 connecting from the primary side of the pressure control valve 21 to the tip of the discharge flow passage 5,
A pressure control valve 25 and a pressure gauge 26 are also interposed in the branch pipe 24, and an inert gas adjusted to a predetermined pressure by the pressure control valve 25 is discharged from the tip of the discharge flow path 5 through the branch pipe 24. It is designed to be sprayed toward the molten metal. In addition to argon, helium, nitrogen, xenon, or the like is used as the inert gas.

Next, the construction of each part of the above molten metal supply pump will be described in more detail with reference to FIGS. First, FIG. 2 shows a partial cross section of a closed container forming a pressurizing chamber. As is clear from this figure, the closed container 2 has a cylindrical intermediate ring 29 sandwiched between a bottom plate 27 and a canopy 28, and a wedge 3 which is press-fitted in the coupling pin 30 and in a direction perpendicular to its axis.
It is configured by fastening with 1. Of these, the connection port 32 for connecting the lower end of the guide tube 10 to the center of the canopy 28.
Is formed. On the other hand, an outflow passage 33 that communicates from the inside of the pressurizing chamber 3 to the outside thereof is formed in the bottom plate 27 as a part of the discharge flow passage, and one end opening portion inside thereof is provided as an upward discharge outlet 9 facing the guide cylinder 10. It is opened at the bottom of the pressure chamber 3.
Here, the discharge flow path 5 is the above-mentioned outflow path 3 which constitutes the upstream part thereof.
3, a joint pipe 34 connected to the upper end thereof, and an extension pipe 35 connected to the upper end thereof. The pressure chamber 3
A wall body 36 surrounding the discharge port 9 formed by the one end opening of the discharge flow path 5 is formed at the bottom of the discharge flow path 5, and the wall body 36 prevents the shaft of the discharge valve 8 from swinging so that the tip head portion thereof is set to the discharge port 9. It is designed so that it can be guided accurately. Further, an inflow path 37 communicating from the inside of the pressurizing chamber 3 to the outside thereof is formed in the bottom plate 27 of the hermetic container, and one end opening portion on the outside thereof is opened upward in the molten metal in the furnace 1 as the intake port 4. I am doing it.

As shown in FIG. 3, the bottom plate 27 has an intake port 4
A pair of columns 38 are erected across the two, and an intake port 4 is provided between them.
A suction valve 7 forming a valve body for opening and closing is provided so as to be able to move up and down. The air cylinder 14 is connected to the upper end of the intake valve 7 as an ascending / descending actuator, and the air cylinder 14 is fixed to a mounting plate 39 installed between columns 38. Therefore, by driving the air cylinder 14, the intake valve 7 moves up and down along its axial direction, and the intake port 4 is closed by the downward movement thereof, and the intake port 4 is closed when the intake valve 7 is raised.
Is opened. As shown in FIG. 4, a large-diameter hole 40 is formed around the intake port 4 to prevent the run-out of the suction valve 7, and a part of the hole 40 is further enlarged to the open intake port 4. The sprue 41 for promoting the inflow of the metal hot water is formed.

Next, FIG. 5 shows a partially cutaway upper portion of the closed container. As is clear from this figure, a pair of upper and lower flanges 42A and 42B are provided at the upper end of the guide cylinder 10,
A pair of columns 43 are erected on the upper flange 42B with the central portion of the guide cylinder 10 interposed therebetween. Then, a mounting plate 44 is installed on the upper end of the column 43, and an air cylinder 15 for raising and lowering the discharge valve 8 is fixed to the mounting plate 44.
On the other hand, a flexible flange-shaped heat resistant seal plate 11 is fixed to the upper portion of the discharge valve 8. In this example, heat-resistant seal plate 1
1 is a circular thin metal plate (SUS304) with a thickness of 0.2 mm. A mounting hole 45 for fixing to the discharge valve is formed at the center of the metal plate as shown in FIG. A fixing hole 46 through which the bolt is inserted is formed. As shown in FIG. 5, the heat-resistant seal plate 11 has a mounting hole 45 at the center thereof.
While being sandwiched between the upper end surface of the discharge valve 8 and the airtightly fixed by a screw part 47 inserted into the guide tube 10, a peripheral edge of the guide tube 10 is fixed by a bolt 48 inserted into the fixing hole 46.
Is fastened with airtightness between a pair of flanges 42A and 42B forming the upper end opening edge.

Here, the heat-resistant seal plate 11 maintains the airtightness of the pressurizing chamber 3 to prevent the inert gas injected into the pressurizing chamber 3 from leaking to the outside from the guide cylinder 11, and the exhaust valve 8 During operation, the central portion flexes and deforms up and down by several millimeters in conjunction with the discharge valve 8 while maintaining airtightness. Therefore, a space 49 is formed between the pair of flanges 42A and 42B to allow the flexible deformation of the heat resistant seal plate 11, and the discharge valve 8 is provided.
The ascending / descending stroke of is limited within the bending deformation limit of the heat resistant seal plate 11. Since the intake valve 7 is of a type in which the intake port 4 is opened and closed from the outside of the pressure chamber 3, it is not necessary to provide the heat-resistant seal plate as described above on the intake valve 7 side, but the inside of the pressure chamber 3 is not required. The inlet port 4 may be opened and closed to form a suction valve, and the heat resistant seal plate 11 as described above may be installed in the suction valve.

Next, FIG. 7 shows the tip of the discharge channel. As is clear from this figure, the extension pipe 3 forming the discharge flow path 5
A cylindrical male screw 50 is attached to the tip of 5, and a ring-shaped upper frame 51 is attached to the male screw 50. Further, a ring-shaped fixing plate 52, a receiving seat 53, and a lower frame 54 are sequentially provided under the upper frame 51, and these are fastened with bolts 55 and nuts 56. this house,
The receiving seat 53 is provided with a lateral hole 57 that opens inside and outside thereof.
The end of the branch pipe 24 for supplying the inert gas is connected to the lateral hole 57. Therefore, the molten metal discharged from the tip of the discharge flow path 5 (extension pipe 35) can be exposed to the inert gas to prevent its oxidation. Further, between the fixed plate 52 and the seat 53, a porous nozzle plate 6 for discharging the molten metal sent through the discharge channel 5 as described above.
Is sandwiched. The nozzle plate 6 is formed of a heat-resistant member having a predetermined thickness as a base, and a plurality of minute hot water holes 6A having a predetermined flow path resistance and having a diameter of several millimeters are bored therein. In particular, the nozzle plate 6 allows the molten metal to pass therethrough under the pressure of the inert gas, and the metal melt remaining in the discharge passage due to the discharge valve 8 closing the discharge passage 5 becomes impermeable due to its surface tension. As described above, the cross-sectional area and the number of perforations of each hot water passage 6A are set. Then, according to the nozzle plate 6, the flow of the molten metal is stopped at the same time when the discharge flow path 5 is closed, and the molten metal leaks from the tip of the discharge flow path 5 until the discharge flow path 5 is restarted. Can be prevented. It should be noted that the nozzle surface of that kind is not provided and the tip of the discharge flow path 5 is simply bent into a hook shape as shown in FIG. You may do it.

The operation of the pump constructed as described above and the method for quantitatively supplying the molten metal by the pump will be described below. First, in using the pump of the present application, the closed container 2 is placed in the furnace 1 as shown in FIG. 9, and is fixed in a state in which the molten metal is soaked. Further, the molten metal surface L is filled with, for example, sulfur hexafluoride having a larger specific gravity than air, thereby shielding the molten metal from the atmosphere and preventing its oxidation.
However, since the molten metal near the surface of the molten metal and near the bottom of the furnace often contains impurities, it is preferable to immerse the closed container 2 in the vicinity of the middle of the molten metal. can do.

In order to supply the molten metal to the hot water supply target, first, as shown in FIG. 10, while the inert gas in the pressurizing chamber 3 is being discharged through the gas pipe 20, the suction valve 7 is raised to keep the intake port 4 constant. It is opened for a period of time, so that an appropriate amount of molten metal can be made to flow into the pressurizing chamber 3 from the inlet 4. Then, after a lapse of a certain time, the intake valve 7 is lowered to close the intake port 4 as shown in FIG. 11, while the inert gas is introduced from the gas pipe 20 through the guide cylinder 10 onto the molten metal surface in the pressurizing chamber 3. Is injected, and the inside of the pressurizing chamber 3 is pressurized thereby. Thus, the pressure of the inert gas acting on the pressurizing chamber 3 is a set value (for example, 800 to 1500 mmHg≈
After reaching 100 to 200 kPa), the discharge valve 8 is operated upward as shown in FIG. 12 while keeping the intake port 4 closed to open the one end opening (discharge port 9) of the discharge flow path for a certain period of time.

The gas pipe 20 may be closed when the pressure of the inert gas acting on the pressurizing chamber 3 reaches a set value, and the discharge flow path 5 may be opened for a certain period of time in that state. However, preferably, in order to prevent the pressure drop due to the extrusion of the molten metal in the pressurizing chamber 3, the inert gas is continuously injected into the pressurizing chamber 3 even while the discharge flow path 5 is open, and The pressure of the acting inert gas is maintained at the initial set pressure.
As a result, the molten metal in the pressurizing chamber 3 is pushed out of the pressurizing chamber 3 at a substantially constant flow rate under a constant pressure of the inert gas, and is supplied to the hot water supply target from the discharge port 9 through the discharge passage 5. Supplied. Then, after a lapse of a certain period of time, the discharge flow path 5 is closed, the inert gas filling the pressure chamber 3 is discharged from the gas pipe 20 to the outside of the pressure chamber 3, and the intake port 4 is opened for a certain period of time. Hot water is repeatedly supplied to the hot water supply target. According to this, the molten metal taken into the pressurizing chamber 3 is quantitatively supplied to the hot water supply target by setting the pressure of the inert gas and the opening time of the discharge flow path 5. can do.

As described above, according to the present invention, since the amount of hot water supplied to the hot water supply target is controlled by the pressure of the inert gas and the opening time of the discharge passage 5, the flow rate of the molten metal taken into the pressurizing chamber 3 is controlled. It does not require control, and it suffices to load the molten metal into the pressurizing chamber 3 as much as necessary for the amount of hot water supplied at one time, but the volume of the molten metal taken into the pressurizing chamber 3 is large each time. If they are different, the pressure chamber 3 will differ due to the difference in the head pressure.
The flow rates of the molten metal extruded from the two are different, which causes an error in the amount of hot water supplied. Therefore, the molten metal surface position in the furnace 1 is kept within a certain range (about ± 50 mm), and when the molten metal surface L falls below the lower limit position, the metal to be melted is replenished in the furnace 1 and preferably as described above. The opening time of the inlet 4 is controlled to adjust the flow rate of the molten metal taken into the pressurizing chamber 3.

By controlling the flow rate of the inert gas discharged from the pressurizing chamber 3, the pressurizing chamber 3 is maintained at a predetermined pressure,
By opening the intake port 4 in this state, the flow rate of the molten metal taken into the pressurizing chamber 3 can be adjusted.
Even if the amount of the molten metal taken into the pressurizing chamber 3 is not constant, by setting the pressure of the inert gas to the head pressure as large as possible, the head pressure of the molten metal in the pressurizing chamber 3 may be different. The error of the hot water supply amount can be reduced to zero.

Although the present invention has been described above, the present invention is not limited to the above-described structure, and for example, a hydraulic cylinder or an electromagnetic solenoid is used as an actuator for operating the intake valve or the discharge valve, or a cam mechanism is used. The suction valve and the discharge valve may be operated by utilizing them. Further, the present invention can be applied to supply of molten aluminum as well as magnesium as the molten metal.

[0030]

As is apparent from the above description, according to the present invention, the pressurizing chamber containing the molten metal is pre-pressurized by injecting the inert gas, and after the pressurizing force reaches the set value, Since the discharge passage is opened for a certain period of time, the molten metal in the pressurizing chamber can be quantitatively supplied to the hot water supply target such as the mold without error through the discharge passage while the metal melt is shielded from the atmosphere. For this reason, molding defects due to insufficient hot water supply do not occur, and ignition of hot water due to excessive hot water supply does not occur, and high quality die castings can be efficiently produced with a low defect rate.

In particular, instead of opening and closing the discharge flow path by adjusting the pressure of the inert gas, the discharge flow path is operated by operating the discharge valve after the pressure of the inert gas that has acted on the pressurizing chamber has reached the set value. Since it is opened, the opening time of the discharge passage does not change due to the property of the molten metal in the pressurizing chamber and the head pressure.

Further, since a porous nozzle plate is provided at the tip of the discharge passage to prevent the molten metal from leaking from the tip when the discharge passage is closed, the metal in the discharge passage is prevented. It is possible to minimize an error in supplying the molten metal due to the molten metal, and further possible to prevent the oxidation of the molten metal due to the outside air entering the discharge passage during standby.

Further, since the flange-shaped heat-resistant seal plate is fixed to the upper part of the discharge valve to seal the pressurizing chamber, the pressure of the inert gas acting on the pressurizing chamber is properly controlled. In addition, since the heat-resistant seal plate is flexible, the discharge valve can be operated while maintaining the airtightness within the limit range of the bending amount.

[Brief description of drawings]

FIG. 1 is a schematic view showing a pump according to the present invention.

FIG. 2 is a vertical sectional view of an airtight container that constitutes the pump.

FIG. 3 is a partial cross-sectional view showing an example of a suction valve device.

FIG. 4 is a cross-sectional view of the closed container.

FIG. 5 is a partial cross-sectional view showing the upper part of the closed container.

FIG. 6 is a plan view of the heat-resistant seal plate.

FIG. 7 is a partial cross-sectional view showing the tip of the discharge flow path.

FIG. 8 is a schematic cross-sectional view showing an example of changing the discharge flow path.

FIG. 9 is a partial cross-sectional view showing a usage state of the pump according to the present invention.

FIG. 10 is a schematic view showing a state where molten metal is taken into the pressurizing chamber.

FIG. 11 is a schematic view showing a state in which an inert gas is injected into the pressure chamber.

FIG. 12 is a schematic view showing a state in which molten metal is supplied from a pressurizing chamber to a hot water supply target.

FIG. 13 is a sectional view showing a conventional pump.

FIG. 14 is a sectional view showing another form of a conventional pump.

FIG. 15 is a sectional view showing another form of a conventional pump.

[Explanation of symbols]

1 furnace 2 closed container 3 pressure chamber 4 intake 5 discharge channels 6 nozzle plate 7 Inhalation valve 8 discharge valve 9 Discharge port (opening at one end of discharge flow path) 10 guide tube 11 Heat-resistant seal plate 12 Operation system 14 Air cylinder 15 Air cylinder 18 Gas supply system (pressure adjusting means) 20 gas pipes

Claims (5)

[Claims] 1. By taking in a molten metal in a furnace into a pressure-adjustable pressurizing chamber, closing the inlet, and then opening a discharge passage that can be opened and closed by operating a discharge valve. A method of supplying the molten metal taken in the pressurizing chamber to a hot water supply target such as a mold through an exhaust flow path, wherein the pressurizing chamber is not closed in the pressurizing chamber before the exhaust flow path is opened. A method for quantitatively supplying a molten metal, comprising injecting an active gas to pressurize the pressurizing chamber, and after the pressure reaches a set value, the discharge valve is operated to open the discharge channel for a certain period of time. . 2. After the metal melt in the furnace is taken into a pressurizing chamber whose pressure can be adjusted through the intake port opened in the metal melt stored in the furnace, the intake port is operated by operating a suction valve. Closed, then pressurized by injecting an inert gas into the pressure chamber, and after the pressure reaches a set value, acts on the pressure chamber with the inlet closed. While maintaining the pressure of the inert gas constant, the discharge flow path connected to the pressurization chamber is opened for a certain period of time by operating the discharge valve, so that the hot water supply target such as a mold is supplied from the pressurization chamber through the discharge flow path. A method for quantitatively supplying a molten metal, which comprises controlling the flow rate of the molten metal sent. 3. A heat-resistant closed container forming a pressure-adjustable pressurizing chamber having an inlet for taking in molten metal in the furnace, a suction valve for opening and closing the inlet, and the pressurizing. A discharge flow path for guiding the molten metal taken into the chamber to a hot water supply target such as a mold, a discharge valve for opening and closing the discharge flow path, and a suction valve for alternately opening the intake port and the discharge flow path. And an operation system for operating the discharge valve, and an inert gas is previously injected into the pressure chamber to control the pressure of the pressure chamber before opening the discharge passage by operating the discharge valve by the operation system. And a control unit for operating the discharge valve so as to open the discharge passage for a certain period of time after the pressure of the inert gas acting on the pressurizing chamber reaches a set value. A molten metal supply pump characterized by being used. 4. The molten metal according to claim 3, wherein a porous nozzle plate is provided at the tip of the discharge passage for preventing the molten metal from leaking from the tip of the discharge passage when the discharge valve is closed. Supply pump. 5. The discharge valve is a rod-shaped heat-resistant seal plate which is provided so as to be capable of moving up and down on one end opening of a discharge flow path which opens at the bottom of the pressurizing chamber, and has a flexible collar-shaped upper part thereof. Is fixed, and the upper part of the closed container is projected onto the molten metal surface of the molten metal stored in the furnace as a guide cylinder for passing the discharge valve into the pressurizing chamber, and the heat-resistant seal plate is provided at the upper end opening edge thereof. The peripheral portion is fastened with airtightness.
The molten metal supply pump described.