JPH1128560A - Molten metal supplying device and molten metal supplying method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ladle for supplying molten metal which prevents the generation of oxide in the inner part of the ladle without leakage from the ladle on the way of transporting, in the ladle for supplying the molten metal and pouring the molten metal into a molten metal receiving hole in an injection sleeve. SOLUTION: The ladle 110 for supplying the molten metal is formed with a molten metal storing chamber 112 for storing the molten metal and a guide tube 140 having the inner diameter smaller than the inner diameter of the molten metal storing chamber 112. At least one of through-hole 140a is bored on the side surface at the lower end part of the guide tube 140 and also, a closing plate closing the opening hole part at the lower end part of the guide tube and having the side wall higher than the height position of the rough-holes 140a. Further, a cover plate 114 for coating the upper opening hole part of the molten metal storing chamber 112 through a seal material and is provided also, a suction pipe 120 penetrating the cover plate 114 and sucking gas in the molten metal storing chamber 112, is connected with the molten metal storing chamber 112. Then, an inert gas supplying pipe 170 connected with an inert gas supplying device on the way of suction, is connected with the suction pipe 120 and a wt. detecting means for measuring the wt. of the ladle 110 for supplying the molten metal, is provided between the ladle 110 for supplying the molten metal and a tilting and transporting means.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hot water supply apparatus having a hot water supply ladle for supplying molten metal such as an aluminum alloy or a magnesium alloy to an injection sleeve of a die casting machine or the like, and a hot water supply method using the hot water supply ladle. In particular, it is an object of the present invention to provide a hot water supply ladder and a hot water supply method that can supply clean molten metal free from oxide contamination to an injection sleeve in a short time and with high accuracy.

[0002]

2. Description of the Related Art Conventionally, when a molten metal of a light alloy such as an aluminum alloy or a magnesium alloy is supplied to an injection sleeve such as a die casting machine, for example, a dedicated holding furnace is installed near the die casting machine. A method in which a certain amount of molten metal is drawn from a holding furnace by a ladle (ladle), and is weighed, transported, and poured is the mainstream of practical use, and is described in, for example, Japanese Patent Publication No. 60-25220. .

However, the hot water supply method using a ladle as described above has the following disadvantages. (1) During weighing, transport, and pouring, the molten metal is exposed to the outside air, which causes oxidation to proceed and lowers the temperature of the molten metal. (2) Since the molten metal is poured from the upper opening of the injection sleeve, air is entrapped due to the falling distance of the molten metal, bubbles are generated, and the cleanliness of the molten metal is reduced. Also,
A large-capacity holding furnace is installed near the die-casting machine with the top open, and the hot water supply work is performed intermittently, resulting in large heat dissipation to the surroundings, which not only deteriorates the work environment but also lowers thermal efficiency. Was. For this reason, various attempts have been made to develop a molten metal hot water supply apparatus that can supply a constant amount of hot water to the injection sleeve efficiently with a small amount of heat dissipation in a closed type.

For example, as shown in FIG. 4 to FIG. 6, an inlet / outlet of molten metal is provided at the bottom of a ladle whose upper part is sealed, and the inside of the ladle is communicated with the atmosphere or a vacuum device via an on-off valve. After the molten metal is immersed in the molten metal, the molten metal is taken into the ladle, the on-off valve is closed to shut off the outside air, and when the molten metal in the ladle is discharged, the on-off valve is opened and dropped from the entrance on the bottom (actual As shown in FIG. 7 and FIG. 7, the molten metal in the ladle that can be opened and closed at the lower end is taken in, and the lower part of the ladle is inserted into the injection sleeve with the molten metal port closed. And start discharging,
After the upper surface of the molten metal discharged from the ladle and transferred into the injection sleeve is higher than the ladle molten metal port, start raising the ladle, raise the ladle corresponding to the discharge state of the molten metal, and the molten metal port is always molten in the injection sleeve. (Japanese Patent Publication No. 2-54183).

[0005]

However, such a hot water supply method has the following problems. About the hot water supply method of (1), a. Since the length of the suction port at the bottom of the ladle is short, when pouring into the vertical injection type vertical injection sleeve, it will be poured from the upper part of the injection sleeve and the drop height is high, so that oxide generation and The entrainment of air into the molten metal is caused, and an unclean molten metal containing impurities is supplied into the mold cavity. b. In the case where the entrance and exit of the molten metal are narrowed as shown in FIG. 4 (FIG. 1 attached to the specification), the molten metal is prevented from flowing out of the ladle by the surface tension, but the surface tension is limited and the hole diameter is reduced. Since it cannot be made large, it takes time to inhale and discharge the molten metal. c. The structure in which the perforated plate is provided at the entrance and exit of the molten metal as shown in FIG. 5 (FIG. 2 attached to the specification) and FIG. 6 (FIG. 3 attached to the specification) can cope with a large-diameter entrance, In order to withstand the tension and prevent the molten metal from flowing out, it is necessary to form a considerably fine hole. When the molten metal is poured, the fine hole becomes a passage resistance and a. Similarly, the molten metal cannot be discharged in a short time.

[0006] Regarding the hot water supply method of (2), a. When introducing the molten metal into the ladle, raise the valve rod to open the inlet, sink the ladle in the molten metal of the holding furnace, and when the desired amount of hot water is supplied, lower the valve rod, close the inlet, and transfer the ladle. However, since the ladle has been immersed in the holding furnace, oxides are generated in the molten metal attached to the outer peripheral surface of the ladle. This oxide falls into the injection sleeve and reduces the cleanliness of the molten metal. b. If the sealing property between the valve stem and the valve seat surface of the ladle is incomplete during the transportation of the ladle, the molten metal will drop, contaminating the working environment and making the supply of hot water inaccurate.

An object of the present invention is to eliminate such disadvantages and to provide a hot water supply apparatus and a hot water supply method having a hot water supply ladle which can supply an accurate and accurate amount of hot water in a short time.

[0008]

In order to solve the above problems, a hot water supply apparatus of the present invention is a hot water supply apparatus for supplying molten metal to an injection sleeve for injecting molten metal into a mold cavity of a mold apparatus. There is a hot water supply ladle for the hot water supply device,
A hot-water storage chamber for storing the molten metal, and a conduit connected to the lower surface of the hot-water storage chamber and hanging downward from the hot-water storage chamber and having an inner diameter smaller than the inner diameter of the hot-water storage chamber; And at least one through hole for introducing the molten metal is provided, and a closing plate having a side wall higher than a height position of the through hole is provided by closing an opening at a lower end of the conduit, and an upper portion of the hot water storage chamber is provided. A lid plate for covering the opening with a sealing material is provided, and a suction pipe that penetrates the lid plate and sucks gas in the hot water storage chamber is connected to the hot water storage chamber, and is connected to the suction pipe. A vacuum suction device is provided, and an inert gas supply pipe connected to the inert gas supply device is connected during the suction,
In addition to the tilting / transferring means for the hot water supply ladder, a weight detecting means for measuring the weight of the hot water supply ladder is provided between the hot water supply ladder and the tilting / transferring means.

In the second invention, the weight detecting means in the first invention is a load cell or a magnecell.

Further, the hot water supply method according to the third invention is characterized in that
In the hot water supply apparatus according to the first or second invention, the hot water supply ladle is transferred and immersed in the holding furnace such that the upper end of the weir plate is lower than the molten liquid level of the holding furnace, and the vacuum suction device is driven to drive the conduit. Vacuum suction of the molten metal in the holding furnace into the hot water storage chamber through the through hole of
When the measured value of the weight detecting means reaches a predetermined weight, the vacuum suction operation is stopped and the hot water supply ladle is transferred to the injection sleeve installation position while maintaining the state, and the conduit is fed into the tilted injection sleeve. Then, an inert gas was injected into the hot water supply ladle and pressurized to discharge the molten metal in the hot water supply ladle to the injection sleeve.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS According to a first aspect of the present invention, there is provided a hot water supply apparatus for supplying molten metal to an injection sleeve for injecting molten metal into a mold cavity of a mold apparatus. A hot-water storage chamber for storing the molten metal, and a conduit connected to the lower surface of the hot-water storage chamber and hanging downward from the hot-water storage chamber and having an inner diameter smaller than the inner diameter of the hot-water storage chamber; At least one through hole for introducing molten metal is provided, and a closing plate having a side wall higher than a height position of the through hole is provided to close an opening at a lower end of the conduit, and an upper portion of the hot water storage chamber is provided. A lid plate for covering the opening with a sealing material is provided, and a suction pipe that penetrates the lid plate and sucks gas in the hot water storage chamber is connected to the hot water storage chamber, and is connected to the suction pipe. A vacuum suction device is provided, and an inert gas supply An inert gas supply pipe connected to the apparatus is connected, and a tilting / transporting means for a hot water supply ladder is provided, and a weight for measuring the weight of the hot water supply ladder between the hot water supply ladder and the tilting / transporting means. Since the detection means is provided, the amount of the molten metal taken into the hot water supply ladle can be accurately controlled by the weight detection means. After the molten metal is taken in, the pipe is moved to the position of the injection sleeve when the molten metal is taken up. Atmospheric pressure acts on the molten metal accumulated in the ladle, and the molten metal in the ladle does not leak from the ladle on the way. Also,
Because the inside diameter of the conduit can be larger than that of the prior art,
Can be poured into the injection sleeve in a short time. Also, only the lower end of the conduit is immersed in the molten metal of the holding furnace and the ladle body (hot water storage room)
It is not necessary to immerse the molten metal in the molten metal, so that the molten metal does not adhere to the outer peripheral surface of the ladle body (hot water storage chamber) and the oxide of the molten metal can be minimized. Is high. Discharge of the molten metal in the hot water supply ladle to the injection sleeve is performed by injecting and pressurizing an inert gas, so that oxidation of the molten metal in the hot water storage chamber is prevented, and a clean molten metal containing no oxide can be supplied.

Further, in the second invention, since the weight detecting means in the first invention is a load cell or a magnecell, the weight of the molten metal can be controlled relatively easily and accurately.

Further, in the third invention, the hot water supply ladle is transferred and immersed in the holding furnace such that the upper end of the weir plate is lower than the molten metal level of the holding furnace, and the vacuum suction device is driven to drive the ladle. Vacuum suction of the molten metal in the holding furnace into the hot water storage chamber through the through hole,
When the measured value of the weight detecting means reaches a predetermined weight, the vacuum suction operation is stopped and the hot water supply ladle is transferred to the injection sleeve installation position while maintaining the state, and the conduit is fed into the tilted injection sleeve. After inserting the hot water, the inert gas is injected into the hot water supply ladle and pressurized to discharge the molten metal in the hot water supply ladle to the injection sleeve, thereby reducing the amount of molten metal adhering to the outside of the hot water supply ladle. Since the operation of supplying hot water to the injection sleeve is performed smoothly, it is possible to reduce the mixing ratio of oxides in the product, thereby realizing good product production.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be described below in detail with reference to the drawings. 1 to 3 relate to an embodiment of the present invention, FIG. 1 is an overall configuration diagram of a hot water supply ladle, FIG. 2 is an explanatory diagram showing steps of a hot water supply method, and FIG. 3 is an explanatory diagram showing control of a hot water supply amount. is there. 4 to 6 relate to an embodiment of the prior art, FIG. 4 is a longitudinal sectional view of a ladle, FIG. 5 is a longitudinal sectional view of a ladle showing another embodiment, FIG. 6 is a plan view of FIG. 7 is a longitudinal sectional view of a ladle according to another embodiment of the prior art.

As shown in FIG. 1, a hot water supply ladle 110 which is a main component of the hot water supply device 100 is roughly divided into a hot water storage chamber 112 formed in a container shape, and a hot water storage chamber having a diameter connected to the lower center of the hot water storage chamber 112. And a downwardly depending tubular conduit 140 having an inner diameter that is much smaller than the inner diameter of the tube.
At least one or more through-holes 140a are formed in the lower end of the conduit 140, and the opening at the lower end of the conduit 140 is
Disk or rectangular lid 150 larger than the diameter of
Around the sealing lid 150, a side wall 160 whose upper end is higher than the height of the through hole 140a is provided to form a weir plate.

On the other hand, the upper end of the hot water storage chamber 112 is covered with a cover plate 114 with a sealing material 116 interposed therebetween.
12 and a bolt-nut joint, and is joined to a transfer arm 200 for transferring or tilting the entire hot water supply ladle 110. Further, a suction port 114 a penetrating the cover plate 114 is provided on the cover plate 114, and a suction tube 120 connected to the vacuum suction device 130 for sucking gas in the hot water storage chamber 112 is connected. ,
An on-off valve 120a is provided. Further, the suction pipe 120 is branched on the way, and the inert gas supply pipe 170 and the on-off valve 17 are opened.
Oa is connected to the inert supply device 180. The transfer arm 200 is connected to an articulated robot (not shown).

At the distal end of the transfer arm 200, there is provided a weight detecting means 210 for measuring the total weight of the hot water supply ladle 110 (hot water storage chamber 112 and conduit 140) and the weight of the molten metal taken into the hot water supply ladle. . In addition, in order to eliminate the influence on the weight after the suction pipe 120 connected to the lid 114 at the top of the hot water storage chamber 112, the vicinity of the lid of the suction pipe 120 is a flexible telescopic tube 120A. As the weight detecting means 210, a commercially available sensor such as a load cell or a magnecell is used.

Hot water supply ladle 110 thus constructed
, The molten metal (molten metal) M stored in the holding furnace F
For example, a hot water supply method for pouring a required amount of hot water into a vertical injection sleeve or a horizontal injection sleeve will be described below.

FIG. 2 illustrates the steps of the operation procedure of the hot water supply method. In the order from step (a) to step (k),
Work is performed sequentially. First, in the step (a), the lower part of the conduit 140 of the hot water supply ladle 110 is immersed in the liquid level of the holding furnace F. The immersion depth is such that the upper end of the side wall 160 is about 50 mm to 100 mm or less from the liquid level. Thereafter, the vacuum suction device 130 is driven to measure the weight by the weight detecting means 210, and the gas in the hot water supply ladle 110 is sucked until the weight of the molten metal taken into the hot water supply ladle 110 reaches a predetermined weight. , The molten metal of the holding furnace F through a through hole 140 a provided at the tip of the conduit 140.
Take it into 12.

After the specified amount of molten metal M is taken into the hot water supply ladle 110, the vacuum suction is stopped, and the hot water supply ladle 110 is pulled up from the holding furnace F while maintaining the state (step (b)), and tilted. (Step (c)), and a part of the molten metal stored in the molten metal reservoir below the conduit formed by the sealing lid 150 and the side wall 160 is discarded. It returns to the state (step (d)). Thereafter, the hot water supply ladle 100 is transferred to the position of the injection sleeve (step (e)).

Next, in the step (f), the injection sleeve is tilted according to the tilt angle of the tilted injection sleeve, and the conduit 140 is lowered into the injection sleeve (step (g)). Next, by driving the inert gas supply device, for example, an inert gas such as nitrogen gas is injected into the hot water storage chamber 112 via the inert gas supply pipe 170 and the suction pipe 120, and the hot water storage 112 The internal negative pressure is increased to the atmospheric pressure, or the pressure is increased to the atmospheric pressure or more, and the molten metal M in the hot water supply ladle 110 is discharged into the injection sleeve S (step (h)).

After the discharge of the molten metal M in the hot water supply ladle 110 is completed, the hot water supply ladle 110 is raised from the injection sleeve S (step (i)), and the hot water supply ladle 110 is changed from the tilted state to the vertical state. It is returned (step (j)). In this state, a small amount of molten metal remains in the molten metal reservoir below the conduit formed by the closed lid 150 and the side wall 160, and the inner surfaces of the hot water storage chamber 112 and the conduit 140 are isolated from the atmosphere. The oxidation of the molten metal is prevented from adhering. Thereafter, the hot water supply ladle 110 is again placed in the holding furnace F.
And the hot water supply operation is performed in preparation for the next shot (step (k)).

Although the process of FIG. 2 described above describes a method for supplying hot water to the vertical injection sleeve, it is also possible to supply hot water to the horizontal injection sleeve without being bound by this.

The above is a series of operation steps. As for the amount of molten metal taken into the hot water supply ladle 110, a predetermined amount of molten metal is taken into the hot water supply ladle 110 while measuring the weight using the weight detecting means 210. Next, control of the amount of molten metal poured into the injection sleeve will be described with reference to FIG.

FIG. 3 is an explanatory view showing the control of the amount of hot water supply, and FIG. 3 (1) shows a state in which the supply and tilting operation of the molten metal ladle 110 in the holding furnace F has been completed and corresponds to the step (d). I do. At this time, the amount of molten metal filling the hot water storage chamber and the conduit is A, and the amount of molten metal in the molten metal reservoir is B. FIG. 3B shows the state of the molten metal ladle 110 after the completion of hot water supply, and corresponds to step (i). Assuming that the amount of molten metal in the molten metal reservoir at this time is C, the amount W of hot water supplied at one time is A + BC.

The amounts of B and C have the same value if the tilt angle is constant in each of the steps (c) and (i), so that they are grasped in advance by measurement. On the other hand, the amount A is the amount of molten metal taken into the hot water storage chamber 112 and the conduit 140 by vacuum suction, and the level difference between the liquid level of the molten metal in the hot water storage chamber and the upper end surface of the side wall 160 of the hot water storage tank and the hot water storage chamber
(2) Since there is a constant relationship with the internal negative pressure, it is possible to control the amount A by controlling the negative pressure during suction, and to control the hot water supply amount W = A + BC to a desired value. Can be done.

In the prior art, the diameter of the molten metal inlet / outlet 6 at the lower end of the ladle 3 shown in FIGS. 4 and 5 is limited to a maximum of about 5 mm to 10 mm in order to withstand surface tension and prevent the molten metal from flowing out. It takes a long time to flow into and out of the ladle, and there are drawbacks such as low efficiency and easy clogging of foreign matter. However, in the present invention, the conduit 14
Since a container-like molten metal reservoir having a closed lid 150 and a side wall 160 is provided at the lower end of the pipe 140, the diameter of the conduit 140 can be reduced to 30 at once.
mm to 50 mm or more, so that the above-described inflow and discharge of the molten metal is performed in a short time. The hot water supply ladle and hot water supply method of the present invention can be applied not only to the vertical injection die casting machine described above but also to a horizontal injection die casting machine.

[0028]

As described above, the present invention exerts the following excellent effects. (1) Due to the atmospheric pressure acting on the molten metal reservoir, the molten metal does not leak from the hot water supply ladle during the transfer after the molten metal is put into the hot water supply ladle. (2) Since the diameter of the conduit can be made several times as large as that of the prior art, the inflow and discharge of the molten metal in the hot water supply ladle can be performed in a short time, so that the efficiency is high. (3) This is a hot water supply method in which only the periphery of the lower end of the conduit is immersed in the holding furnace, and the molten metal does not adhere to the outer periphery of the hot water storage chamber. In addition, since there is molten metal remaining in the molten metal reservoir after pouring of the molten metal into the injection sleeve, it is possible to prevent the inside of the hot water storage chamber and the inside of the conduit from coming into contact with air, thereby preventing generation of unnecessary oxides. (4) Since the hot water supply ladle is provided with the weight detecting means, the weight of the molten metal can be easily and accurately controlled.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a hot water supply ladle according to an embodiment of the present invention.

FIG. 2 is an explanatory view showing steps of a hot water supply method according to an embodiment of the present invention.

FIG. 3 is an explanatory diagram illustrating control of a hot water supply amount according to the embodiment of the present invention.

FIG. 4 is a longitudinal sectional view of a conventional ladle.

FIG. 5 is a longitudinal sectional view of another conventional ladle.

FIG. 6 is a plan view of FIG. 5;

FIG. 7 is a longitudinal sectional view of a ladle according to another conventional example.

[Explanation of symbols]

 Reference Signs List 3 Ladle 6 Melt inlet / outlet 9 Perforated plate 100 Hot water supply device 110 Ladle for hot water supply 112 Hot water storage room 114 Cover plate 114a Suction port 116 Seal material 120 Suction pipe 120a Open / close valve 130 Vacuum suction device 140 Conduit 150 Sealing lid 160 Side wall (dam plate) 170 Non Active gas supply pipe 170a Open / close valve 180 Inert gas supply device 200 Transfer arm M Molten metal (molten metal) F Holding furnace

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Sadayuki Danura 1980, Kogushi-jiki-oki, Obe-shi, Ube-shi, Yamaguchi Ube Industries, Ltd. Machinery and Engineering Division

Claims (3)

[Claims] 1. A hot water supply device for supplying a molten metal to an injection sleeve for injecting a molten metal into a mold cavity of a mold device, wherein the hot water supply ladle includes a hot water storage chamber for storing the molten metal, A conduit having an inner diameter smaller than the inner diameter of the hot water storage chamber and connected to the lower surface of the hot water storage chamber and connected to the lower surface of the hot water storage chamber; And a closing plate having a side wall higher than the height position of the through hole, and a closing plate having a side wall higher than the height position of the through hole is provided. A cover plate for coating is provided, and a suction pipe that penetrates the cover plate and suctions gas in the hot water storage chamber is connected to the hot water storage chamber, and further includes a vacuum suction device connected to the suction pipe, Inactive connected to the inert gas supply device during the suction And a means for tilting / transferring the hot water supply ladle, and a weight detecting means for measuring the weight of the hot water supply ladle between the hot water supply ladle and the tilting / transferring means. A hot water supply device characterized by the following. 2. The hot water supply apparatus according to claim 1, wherein the weight detecting means is a load cell or a magnecell. 3. The hot water supply apparatus according to claim 1, wherein the hot water supply ladle is transferred into the holding furnace so that the upper end of the weir plate is lower than the liquid level of the molten metal in the holding furnace, and is immersed. The apparatus is driven to vacuum suck the molten metal in the holding furnace into the hot water storage chamber through the through hole of the conduit, and when the measured value of the weight detecting means reaches a predetermined weight, the vacuum suction operation is stopped to change the state. The hot water supply ladle is transferred to the injection sleeve installation position while being held, and a conduit is inserted into the tilted injection sleeve. Then, an inert gas is injected into the hot water supply ladle and pressurized so that the inside of the hot water supply ladle is pressurized. A hot water supply method for discharging molten metal to the injection sleeve.