JPH09206911A - Closed hot water supply device and hot water supply method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a closed type molten metal supplying apparatus, in which dripping of the molten metal during transporting a ladle is not developed and the supplying accuracy of the molten metal is high and the high quality molten metal without mixing oxide can continuously and stably be supplied. SOLUTION: In the apparatus for supplying the molten aluminum alloy into an injection sleeve, the ladle 20 dipped and suspended into a melting and holding furnace 10 for the molten metal and providing an opening/closing device composed of a sucking hole 20c arranged at the bottom side part and a valve rod 22 and a valve rod cylinder 24 at the outer part, a ladle suspension support elevating/lowering means 60, a guide pipe 28 inserted into the ladle at the one end and into the injection sleeve at the other end and a gas pouring means 30 for pressurizing the molten metal surface, are provided. Further, an oxide removal device for removing the oxide film on the molten metal stuck to the top end part 28a at the guide pipe discharging side, is provided, and the molten metal discharging side of the guide pipe is inclined downward and also, the elevating/lowering of the ladle is parallel inclined with the injection sleeve.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealed hot water supply device for supplying a molten metal such as an aluminum alloy or a magnesium alloy to an injection sleeve of a molding device such as a die casting machine, and a hot water supply method for the sealed hot water supply device, and more particularly, accuracy of hot water supply. The present invention relates to a sealed hot water supply device in consideration of the improvement of water temperature and measures against molten metal oxides.

[0002]

2. Description of the Related Art Conventionally, in order to supply a molten metal such as an aluminum alloy or a magnesium alloy to an injection sleeve of a die casting machine, conventionally, as shown in FIG.
Using a mechanical mechanism, the ladle 20 that has taken out the molten metal inside rises or moves laterally while drawing an arcuate locus to move to the position of the inclined injection sleeve 200, and then,
The ladle inversion method of pouring the molten metal in the ladle 20 into the injection sleeve has been adopted. Further, as shown in FIG. 7, a lid 20a is provided on the top and an opening (suction port 20c) is provided on the bottom, and an unsealed ladle 20 having an air vent 20d on the lid 20a is dipped into the melting and holding furnace 10 to form the bottom. Opening 2
After the molten metal has penetrated into the ladle 20 from 0c, the opening 2
After closing 0c, the ladle 20 is moved to the position of the inclined injection sleeve 200, and while the ladle 20 is inclined along the axis of the injection sleeve 200 while the bottom of the ladle is inserted into the injection sleeve 200, A method has also been employed in which the opening 20c is changed from the closed state to the open state, and the molten metal inside the ladle is naturally dropped and supplied (supplied with hot water) into the injection sleeve 200. This method is called the bottomed ladle method.

[0003]

However, in any of the above-mentioned ladle inversion method and bottomed-out ladle method, the pouring port (ladle discharge port) to the injection sleeve is the ladle body when pouring the molten metal into the ladle. Since the molten metal is immersed in the melting and holding furnace, the molten metal not only enters the inside of the ladle but also adheres to the outer periphery of the ladle, moves the ladle to the position of the injection sleeve, and adheres to the outer periphery of the ladle during the subsequent pouring operation. The molten metal reacts with oxygen in the air to produce oxides,
In addition, this drops during pouring and drops into the injection sleeve together with the molten metal inside the ladle. There is a problem in that the molten metal falling product forms an oxide upon contact with air, so that the oxide is mixed into a cast product after die casting, which causes deterioration in quality. Further, in the above-mentioned bottomed ladle system, when the opening (suction port 20c) is opened downward in the center of the bottom and the seal of the switchgear after the molten metal is taken into the ladle is incomplete. In addition, there is a problem that the molten metal is dripped when the ladle is transferred to the injection sleeve, which is not only dangerous but also significantly contaminates the working environment. Further, if the molten metal surface of the melting and holding furnace is different each time the molten metal is supplied, the amount of molten metal taken into the ladle 20 will be slightly different, resulting in variations in the amount of molten metal poured each time, and as a result, the amount of molten metal supplied to the injection sleeve. Since there are variations, the hot water supply accuracy is low and the quality of the cast product cannot be kept uniform. Further, in the above-mentioned ladle (the ladle 20 in FIG. 6 and the ladle 20 in FIG. 7), the height of the molten metal dropped into the injection sleeve at the initial stage of hot water supply is large,
At the time of a large drop height, it was feared that the surrounding air was engulfed and casting defects such as blowholes were generated in the cast product.

[0004]

In order to solve the above problems, in the present invention (first invention), a closed type hot water supply for supplying molten metal of aluminum alloy or magnesium alloy into an injection sleeve of a die casting machine or the like. An apparatus, which is provided with a suction port for molten metal which is immersed and suspended in a melting and holding furnace for molten metal and which is provided so as to project to the side of the bottom and which is opened upward and which is capable of interrupting communication A ladle provided with an opening / closing device composed of a valve rod cylinder for raising and lowering a valve rod on the outside of the ladle body, the ladle suspension supporting elevating means, one end housed in the ladle and the other end projecting from the ladle and the injection. The conduit is inserted into the sleeve for pouring the molten metal in the ladle to the injection sleeve, and the means for injecting a pressurized gas for pressurizing the liquid surface of the molten metal in the ladle, and the conduit discharge The injection device is provided with an oxide removing device for removing an oxide film of the molten metal adhering to the tip end, wherein the molten metal discharge side of the conduit is inclined downward and the raising and lowering direction of the ladle suspension support elevating means is inclined. The structure is inclined parallel to the sleeve. A hot water supply method for a closed hot water supply device according to a second aspect of the present invention is the closed hot water supply device according to the first aspect of the present invention, which is a hot water supply method for a closed hot water supply device for supplying molten metal into an injection sleeve. After the tip is inserted near the bottom surface of the injection sleeve and stopped, hot water supply is started and the molten metal immersion depth at the tip of the conduit discharge side is increased by the rise of the melt liquid level in the injection sleeve as the hot water supply progresses. When the predetermined value is reached, the molten metal is supplied while raising the ladle integrally with the conduit at the same speed as the rising of the molten metal liquid level so as to keep the predetermined molten metal immersion depth constant.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The closed hot water supply apparatus of the present invention is a closed hot water supply apparatus for supplying molten metal of aluminum alloy or magnesium alloy into an injection sleeve of a die casting machine or the like, which is provided in a melting and holding furnace for molten metal. Opening and closing is provided with a molten metal suction port that is soaked and suspended, and that protrudes to the side of the bottom and that is open upwards and that can freely block communication, and that shuts off the communication port and a valve rod cylinder for lifting and lowering the valve rod. A ladle provided with a device outside the ladle body, the ladle suspension supporting elevating means, one end housed in the ladle and the other end protruding from the ladle and inserted into the injection sleeve, and the molten metal in the ladle is A conduit for pouring molten metal into the injection sleeve and means for injecting pressurized gas for pressurizing the surface of the molten metal in the ladle are provided, and an oxide film of the molten metal attached to the tip of the conduit on the discharge side. Comprising an oxide removing device for removing molten metal discharge side of the conduit, with tilting downward, it is constituted that is inclined parallel to the said injection sleeve inclined lifting direction of the ladle suspended with lifting means. Therefore, it is necessary to immerse the ladle in the melting and holding furnace containing the molten metal, suck the molten metal into the ladle through the molten metal inlet of the upper opening projecting to the side of the bottom of the ladle, take it in, and then pass through the ladle body. Instead, the intake port is closed by an opening / closing device consisting of a valve rod that can move up and down the side of the ladle body in the vertical direction and a valve rod cylinder for raising and lowering the valve rod. In the bottomed ladle system provided with a sealing lid for sealing, a gas seal between the sealing lid and the valve rod is required, but in the present invention, since the valve rod does not have a structure that penetrates the sealing lid, There is no need to consider gas sealing with the ladle sealing lid. After the molten metal has been taken up into the ladle, operate the ladle suspension support elevating means to transfer the ladle and insert the tip of the conduit discharge side connected to the ladle to near the top surface of the plunger tip at the bottom of the injection sleeve and pressurize gas. Is blown into the ladle, and the molten metal in the ladle is supplied to the injection sleeve through the conduit by this pressing force. Further, in the second invention, the molten metal adhering to the outer periphery of the tip of the conduit discharge side comes into contact with the air to form molten oxide, which is deposited and developed, and falls off due to gravity or vibration during hot water supply and mixes into the injection sleeve. Then, the outer periphery of the tip of the conduit discharge side is cleaned with an oxide removing device at an appropriate frequency so as not to deteriorate the quality of the molded product. When supplying molten metal from the ladle to the injection sleeve, insert the tip of the conduit on the discharge side up to the bottom surface of the injection sleeve and stand still, then start the hot water supply and the molten metal in the injection sleeve as the hot water supply progresses. When the molten metal immersion depth at the tip of the discharge side of the conduit reaches a predetermined value due to the rise of the liquid level, it is integrated with the conduit at the same speed as the rise of the molten metal liquid level so as to keep the predetermined molten metal immersion depth constant. If the hot water is supplied while raising the ladle, it is possible to prevent splashing and splashing that occur when the molten metal falls, so that air entrapment in the molten metal is prevented, and the depth of immersion of the molten conduit in the injection sleeve is prevented. Because the hot water supply proceeds in a constant shallow condition,
The amount of molten metal adhering to the outside of the conduit is a constant minute amount, and it is also possible to remove the oxide by cleaning the outside every time. Therefore, in the closed-type hot water supply apparatus of the present invention, the hot water supply conditions are made uniform every time as compared with the prior art, so that the hot water supply accuracy is high, less molten metal is dropped during ladle transfer, and less molten oxide is mixed. Therefore, the quality of the cast product can be kept good.

[0006]

Embodiments of the present invention will be described below in detail with reference to the drawings. 1 to 5 are all related to an embodiment of the present invention, FIG. 1 is an overall configuration diagram of a closed type hot water supply device, FIG. 2 is an enlarged vertical sectional view of a main part of the closed type hot water supply device (during hot water supply), and FIG. FIG. 4 is a front view of the non-working oxide removing device showing an AA view of FIG. 2, and FIG. 5 is B of FIG. FIG. 6 is an enlarged vertical cross-sectional view of a main part of the closed-type hot water supply device showing the position state of the oxide removing device during the work viewed from the position B.

As shown in FIG. 1, a hermetically sealed hot water supply apparatus 1 according to a first aspect of the present invention is a ladle suspension-supporting lifting cylinder in which an upright cylindrical ladle 20 is inclined and fixed to a building (or structure) 50. The piston 60 is connected to the tip of a piston rod 60a and suspended, and is held so that most of it is immersed in the melting and holding furnace 10. The upper end of the ladle 20 is bolted by a canopy 20a and a sealing lid 20b, respectively. An opening (suction port 20c) that is joined and sealed via a nut and that is provided so as to project to the side of the bottom and that allows the molten metal M in the melting and holding furnace 10 to be sucked into the ladle 20 (suction port 20c)
And a valve rod cylinder for connecting and disconnecting the inlet 20c and the melting and holding furnace 10, and a valve rod cylinder that is a means for raising and lowering the valve rod 22 fixedly mounted on the support 24a attached to the canopy 20a. An opening / closing device 40 composed of 24 is provided.

On the other hand, the canopy 20a and the sealing lid 20b have one end penetrating downward into the ladle 20 and the other end curved to incline the inclined axis X of the injection sleeve 200 of the die casting machine.
A conduit 28 that is inclined and descends along −X is attached, and an inert gas supplied from an inert gas supply device 70 such as N ₂ gas, Ar gas, or CO ₂ gas is injected into the ladle 20. An active gas pipe 30 is provided.
Ladle support 2 attached to the top of the sealing lid 20a
As described above, 6 is connected to the tip of the piston rod 60a of the ladle suspension support elevating / lowering cylinder 60.
Is movable up and down along an integrally inclined axis X-X.

As the pressurized gas, in addition to the inert gas, waste gas in the factory, combustion gas, or normal air can be used, but in order to prevent the oxidation of the molten metal, the gas containing no oxygen is used. Active gas (N ₂ gas, Ar gas, CO ₂ gas, etc.) is desirable. The inert gas pipe 30 is configured so as to pass through the temperature adjusting device 90 and be heated to a desired temperature after exiting the inert gas supply device 70. The supply time can be controlled arbitrarily. Further, the three hydraulic cylinders, which are the ladle suspension support lifting cylinder 60, the valve rod cylinder 24, and the cleaning tool lifting cylinder 11 of the oxide removing apparatus 100 described later.
The hydraulic pipes of 0 are independently connected to a hydraulic unit (not shown), and the hydraulic unit is connected to a programmable controller (not shown) to receive an operation command from the programmable controller and operate.

Also, as shown in FIGS.
An oxide removing device 100 for removing and cleaning the molten metal and the molten oxide adhering to the outer periphery of the discharge portion tip 28a is disposed on the conduit discharge side of the support 26. As shown in FIGS. 4 to 5, the oxide removing apparatus 100 includes a cleaning tool opening / closing cylinder 120 and a cleaning tool opening / closing cylinder 120 that includes a pair of left and right cleaning tools 122 that grip the outer periphery of the conduit 28 and slide in the conduit axial direction. The cleaning tool lifting cylinder 110 is configured to move the cylinder 120 up and down in the axial direction of the conduit, and the cleaning tool opening and closing cylinder 120 is retracted upward as shown in FIG. 2 while the molten metal is being supplied. As shown in FIG.
The cleaning tool 122 is slid up and down on a to remove the molten metal and molten oxide adhering to the outer circumference of the conduit. The cleaning tool lifting cylinder 110 and the cleaning tool opening / closing cylinder 120 may be air cylinders instead of hydraulic cylinders.

The operation of the sealed hot water supply apparatus 1 of the present invention having the above-described structure will be described. First, in the ladle 20 held in the state as shown in FIG.
4 is operated to raise the valve rod 22 and open the suction port 20c to discharge the gas in the ladle 20 while melting and holding the furnace 10.
The molten metal M is naturally sucked into the ladle 20. Ladle 20
The amount of molten metal sucked in is adjusted by the height of the ladle 20 buried in the melting and holding furnace 10 or is adjusted by a molten metal level detection rod (not shown) arranged outside the ladle 20, but in this case, As shown in FIG. 2, the molten metal liquid level in 20 is
It is desirable that the amount of the inert gas sealed in the ladle 20 is made as small as possible by contacting with the lower surface of the sealing lid 20b or keeping the sealing lid 20b in a state in which it is sliding. After this,
Inert gas supply device 7 via inert supply control device 80
When 0, the inert gas is supplied into the ladle through the inert gas pipe 30. In addition, the inert gas is used in the temperature control device 9
A value close to the molten metal temperature due to 0, for example, 250 to 70
It is desirable to heat and supply to a constant temperature state within the range of 0 ° C.

Next, after the valve rod 22 is lowered to close the suction port 20c and the suction of the specified amount of the molten metal into the ladle 20 is completed, the ladle suspension supporting lift cylinder 60 is operated to operate the conduit 2
The tip of the discharge part of No. 8 is lowered to adjust the discharge part tip 28a of the conduit 28 close to the upper surface of the plunger tip 200a in the injection sleeve 200, and a low pressure of about 1.2 kg / cm ^{2 is applied in} advance. When the pressurized inert gas is injected into the ladle 20, the molten metal surface inside the ladle 20 is pressurized and flows through the conduit 28 to drop from the tip 28a of the discharge portion 28a of the conduit 28 to start pouring into the injection sleeve 200. When the pouring work is started, the injection sleeve 20
Since the liquid level of the molten metal entering 0 starts to rise gradually, conduit 2
After the tip 28a of the discharge portion 8 of No. 8 is immersed in the melt surface by about 20 mm, the conduit 28 is moved at the same speed as the rising speed of the melt surface.
Radle 20 so that By doing so, hot water is supplied into the injection sleeve 200 while maintaining the molten metal immersion depth of the discharge portion tip 28a at the above-mentioned constant value of about 20 mm. This immersion depth is usually 20 mm
Within the range of up to 50 mm, it is preferable that the amount is as small as possible, because the amount of molten metal that adheres to the outer circumference of the conduit discharge side tip portion can be reduced.
The amount of hot water supplied to the injection sleeve 200 is, for example, lower than or equal to the lower end of the molten metal level detecting rod 150a immersed in the ladle at a certain depth due to the molten metal liquid level in the ladle being lowered, The supply of the inert gas is stopped at the time when the flowing current is in the non-conducting state, so that the molten metal reaches a predetermined amount. In this way, a specified amount of molten metal is supplied from the ladle 20 into the injection sleeve 200 by supplying the inert gas for a specified time. The above-described series of working procedures (immersing the ladle 20 in the melting and holding furnace, the valve rod 2
Intake work by raising 2 and suction port 20c by lowering the valve rod
A sequence start / stop program of closing, inserting the tip of the conduit discharge part 28a into the injection sleeve, injecting an inert gas into the ladle, raising the conduit during hot water supply, stopping inactive gas injection, etc. is input to the programmable controller in advance, and this program is entered. The work can be automatically continued according to the above. Then, every time the hot water is supplied every time, the oxide removing device 1 is regularly used.
00 is used to clean the outer circumference of the conduit discharge side tip portion 28a to remove the generated molten oxide.

Further, when the hot water is supplied to the injection sleeve 200, since the immersion depth of the discharge-side tip end portion 28a of the conduit 28 is kept substantially constant, the molten metal falls into the injection sleeve 200 and is splashed. No splashes and little air entrapment. Further, the state of the molten metal that adheres to the outside of the discharge-side tip portion 28a is constant every time, the amount of the molten metal also decreases, and this is removed and cleaned every time, so that almost no molten oxide is mixed into the molded product. To be done. That is, for example, by using the oxide removing apparatus 100 shown in FIGS. 2 to 5 to clean the outside of the lower end of the conduit at an appropriate frequency as needed, it is possible to prevent the molten oxide from being mixed into the product. It

[0014]

As described above, in the sealed hot water supply apparatus of the present invention, there is almost no dripping during the transfer of the ladle,
In addition, the accuracy of hot water supply is improved, and hot water is supplied by the pressing force by blowing pressurized gas, and the outer circumference of the tip end of the conduit discharge side is cleaned as often as necessary, so there is almost no mixing of oxides, and during pouring. Since the entrainment of air is prevented as much as possible, it is possible to continuously and stably supply high-quality cast products without casting defects.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of a closed water heater according to an embodiment of the present invention.

FIG. 2 is an enlarged vertical cross-sectional view of a main part of the sealed hot water supply device (during hot water supply) according to the embodiment of the present invention.

FIG. 3 is an enlarged vertical cross-sectional view of a main part of the sealed hot water supply device (during oxide removal cleaning) according to the embodiment of the present invention.

FIG. 4 is a front view of the oxide removing apparatus in a non-working state, which is taken along the line AA of FIG. 2.

5 is an enlarged longitudinal cross-sectional view of a main part of the sealed hot water supply device showing the position state of the oxide removing device during the work as viewed from BB in FIG.

FIG. 6 is an explanatory diagram of a conventional hot water supply device.

FIG. 7 is an explanatory diagram of a conventional hot water supply device.

[Explanation of symbols]

 1 Closed Hot Water Supply Device 10 Melt Holding Furnace 10a Crucible 20 Ladle 20a Canopy 20b Closed Lid 20c Suction Port 22 Valve Bar 24 Valve Bar Cylinder 24a Support 26 Laddle Support 28 Conduit 28a Discharge Port Tip (Discharge Side Tip) 30 Inert Gas Pipe 40 Opening / closing device 50 Building (or structure) 60 Laddle suspension supporting lifting cylinder 60a Piston rod 70 Inert gas supply device 80 Inert gas supply control device 90 Temperature control device 100 Oxide removal device 102 Support 110 Cleaning tool lifting cylinder 120 Cleaning Tool open / close cylinder 122 Cleaning tool 200 Injection sleeve 200a Plunger tip

Claims (2)

[Claims] 1. A closed type hot water supply device for supplying a molten metal of an aluminum alloy or a magnesium alloy into an injection sleeve of a die casting machine or the like, which is soaked and suspended in a melting and holding furnace for molten metal so as to project to the side of the bottom. A ladle provided with an opening / closing device, which is provided outside the ladle body, having an opening / closing device having a suction port for molten metal which is opened upward and which is capable of blocking communication, and a valve rod and a valve rod cylinder for lifting and lowering the communication port, The ladle suspension support lifting means, the injection sleeve having one end housed in the ladle, the other end protruding from the ladle and inserted into the injection sleeve, and pouring the molten metal in the ladle to the injection sleeve; And a means for injecting a pressurized gas for pressurizing the surface of the molten metal in the ladle, and an oxide removing device for removing the oxide film of the molten metal adhering to the tip of the conduit discharge side. , The molten metal discharge side of the conduit, with tilting downward, closed type hot water supply device being characterized in that is inclined parallel to the said injection sleeve inclined lifting direction of the ladle suspended with lifting means. 2. A hot water supply method for a closed hot water supply device for supplying molten metal into an injection sleeve by using the closed hot water supply device according to claim 1, wherein the tip of the conduit on the discharge side is close to the bottom surface of the injection sleeve. After inserting and standing still, hot water supply is started, and when the molten metal immersion depth at the tip of the conduit discharge side reaches a predetermined value due to the rise of the molten metal liquid level in the injection sleeve with the progress of the hot water supply, The method for hot water supply in a hermetically sealed hot water supply device, comprising: raising the ladle integrally with the conduit at the same speed as raising the level of the molten metal so as to keep the molten metal immersion depth constant.