JP3179289B2 - Magnesium water heater - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnesium hot water supply apparatus, and more particularly to a magnesium hot water supply apparatus in which molten magnesium is prevented from being oxidized and burned during supply and discharge.

[0002]

2. Description of the Related Art Conventionally, an inert gas is supplied to a melting pot 2 of a melting furnace 3 as shown in FIG. By lowering the injection piston 6, a certain amount of molten magnesium M is supplied to the molten metal passage 8 inside the base plate 8.
A magnesium hot water supply apparatus 1 has been proposed in which the hot water is supplied into a die casting sleeve 20 of a die casting machine via a hot water supply pipe 10 and a.

[0003] That is, a magnesium hot water supply apparatus 1 is an upright cylindrical melting pot 2 housed inside a melting furnace 3 and provided with a lid (top plate) 4; A base plate 8 having a passage 8a, an injection sleeve 5 having an injection piston 6 erected perpendicularly to the upper surface of the base plate 8 and communicating with the melt passage 8a and having both ends opened and slidable therein; and an opening 8b at one end And a hot water supply pipe 10 connected to the molten metal passage 8a of the base plate 8 which is connected orthogonally to the lower end of the injection sleeve 5 and extends outside the furnace, and a molten magnesium (hereinafter referred to as molten metal) M to the molten metal passage 8a. And a check valve 19 in the middle of the molten metal passage 8 a of the base plate 8. Lid (top plate) 4
An injection cylinder 11 connected to the injection piston 6 via a piston rod 12, a hydraulic cylinder 16 connected to the suction valve 7 via a valve rod 17, and a hydraulic cylinder 19 A for a check valve 19 are mounted on the top of the cylinder. In addition to being fixed, an inert gas injection pipe 9 for enclosing the inert gas into the melting pot 2 is attached. The injection sleeve 5 forms a pressurized chamber for taking out the molten metal M in the melting pot 2 to the outside of the furnace. The injection valve 6 is opened and the check valve 19 is lowered (closed state). After ascending and sucking the molten metal M, the suction valve 7 is closed, the check valve 19 is raised (opened), and the injection piston 6 is lowered, so that the molten metal M filling the molten metal passage 8a is supplied. The die casting sleeve 20 is conveyed to the outside of the furnace via the pipe 10 and connected to the hot water supply pipe 10 via the pipe joint 30 via the hot water supply pipe 14 outside the furnace.
It is discharged into the mold and injected into a die of a die casting machine (not shown) by the advance of the die casting piston 21. By the way, the hot water supply pipe 14 following the hot water supply pipe 10
Is formed in a U-shape after rising at the tip, and the discharge port is directed downward. A heater 18 is mounted around the discharge port to prevent a temperature drop of the molten metal M out of the furnace. Water.

[0004]

However, in the hot water supply pipe having the above-described U-shaped curved discharge portion, the hot water supply to the injection sleeve after the completion of hot water supply to the injection sleeve is not good for each shot, and even after the hot water supply is completed. There is a problem that the molten metal adhering to the inner surface of the hot water supply pipe outside the furnace is dripped little by little, causing a malfunction of the injection piston in the injection sleeve in the horizontal casting die casting machine, and the injection sleeve in the vertical casting die casting machine. There has been a problem that the attachment to the mold becomes incomplete. Further, in each case, if the next operation is waited until the dropping is completely completed, the cycle time becomes longer and the productivity is lowered. Also, when the molten metal is supplied outside the furnace, the discharge pipe of the hot water supply pipe is not completely inserted into the die casting sleeve, so that the discharge section of the hot water pipe touches the outside air to cause oxidation and combustion, resulting in oxides and deteriorating product quality. There was a drawback.

[0005]

According to the present invention, there is provided an injection piston which slides inside an injection sleeve fixed to a base plate suspended from a top plate in a melting furnace. In a magnesium hot water supply device for supplying molten magnesium contained in a melting furnace through a hot water supply pipe communicating with the outside through a molten magnesium passage formed in the base plate, a discharge portion of the hot water supply pipe is inclined. A vertical discharge pipe is joined to the rising hot water supply pipe, and a movable pipe that can move up and down in the vertical direction is joined to the discharge pipe. Further, in the invention according to claim 2, the movable tube is formed as a telescopic tube. Further, according to the third aspect of the present invention, a flameproof gas injection port is provided at the upper end of the discharge pipe so that the flameproof gas is blown into the discharge pipe.

[0006]

According to the present invention, a vertical discharge pipe is joined to a hot water supply pipe which rises obliquely upward at a discharge portion of the hot water supply pipe, and a movable pipe which can move up and down in the vertical direction is joined to this discharge pipe, or joined to the discharge pipe. When the movable pipe is made to be a telescopic pipe, the molten magnesium is supplied after the tip of the movable pipe is immersed inside the external molten metal discharge device such as a die casting sleeve at the time of hot water supply, so the molten magnesium fall distance is small, and The chance of contact with the outside air is small, and oxidation and combustion of the molten magnesium are prevented as much as possible. According to the third aspect of the present invention, a flameproof gas injection port is provided at the upper end of the discharge pipe so that the flameproof gas is blown into the discharge pipe and the die casting sleeve of the die casting machine. When the process is completed, the molten metal is formed at this junction with the surface of the molten metal stopped, and the molten metal adhered to the inner surface of the vertical discharge pipe is quickly discharged, so that the molten metal runs out and there is almost no dripping after the completion of hot water supply. In addition, the oxidizing and burning of the molten metal is prevented by purging the outside air by continuously flowing the flammable gas during the operation or by blowing the flammable gas into the discharge pipe during or for a while after the hot water is supplied. Therefore, it is possible to prevent the oxide from being mixed into the molten metal guided to the die casting machine.

[0007]

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 4 relate to an embodiment of the present invention,
1 is an overall vertical sectional view of a magnesium hot water supply apparatus, FIG. 2 is an enlarged vertical sectional view of a main part of a hot water supply pipe discharge section, and FIGS. 3 and 4 are enlarged vertical cross sectional views of a main part of a hot water supply pipe discharge section showing another embodiment. It is. As shown in FIGS. 1 and 2, in the magnesium hot water supply apparatus 1 of the present invention, the discharge portion 14 </ b> T of the out-of-furnace hot water supply pipe 14 connected to the hot water supply pipe 10 is configured to discharge vertically to the out-of-furnace hot water supply pipe 14 rising obliquely upward. The pipe 14A is joined, and the discharge pipe 14A
A movable pipe 14M slidable up and down on the outer circumference of the discharge pipe 14A is disposed below the lower end of the air pipe 50. The movable pipe 14M is vertically movable by a piston rod 50a of an air cylinder 50 fixed to a side surface of the discharge pipe 14A. Is done. At the center of the blind plate 14P screwed to the top of the discharge pipe 14A, an injection nozzle 40 that penetrates through the blind plate 14P and injects a flameproof gas downward inside the discharge pipe 14A is attached. It is configured such that the flameproof gas supplied by 42 can be injected into the discharge pipe 14A. In the present invention, after the external molten metal supply / discharge device, for example, the die casting sleeve 20 approaches the discharge portion 14T and stops immediately below the discharge tube 14A and the movable tube 14M, the movable tube 14M is driven by driving means such as an air cylinder 50. Then, the molten metal is supplied into the die casting sleeve 20 by lowering the injection piston 6 in the injection sleeve 5 of the magnesium water heater 1. During this supply operation, the supply and injection of the flameproof gas are constantly performed to prevent the molten metal being supplied from being oxidized or combusted by oxygen in the surrounding outside air. At this time, as the liquid level of the molten magnesium M in the die casting sleeve 20 rises, the discharge portion 14
It is desirable to raise the lower end of T. N2 (nitrogen) gas, Ar (argon) gas, SF6
(Sulfur hexafluoride) gas alone or CO 2
2 1 to 5 amount of SF6 per 100 amount of (carbonic acid) gas
A mixed gas to which (sulfur hexafluoride) is added is used. However, although SF6 has a very high effect as a fireproof gas, it is used alone by mixing it with the above-described ratio in carbon dioxide gas because the price alone is higher than the others. The discharge pipe 14A may be a steel pipe or a thin stainless steel pipe, or may be a graphite pipe with a good drainage of molten magnesium.

As described above, by performing the supply, the distance between the lower end of the discharge portion 14T and the liquid surface in the die casting sleeve 20 is greatly reduced, and the discharge portion 1
By covering the lower end of the 4T with the die casting sleeve 20, the contact between the supplied molten magnesium and the outside air is reduced, and the oxidation and combustion are significantly reduced. As described above, by blowing the flameproof gas into the discharge pipe 14A or the movable pipe 14M while supplying the molten magnesium to the die casting sleeve 20, not only the inside of the discharge pipe 14 or the movable pipe 14M but also the inside of the die casting sleeve 20 or The mold cavity is filled with a fireproof gas, and the contact between the supplied molten magnesium and oxygen in the outside air is cut off, so that oxidation and combustion are greatly reduced.

FIG. 3 shows another embodiment of the discharge section 14T, and only the points different from FIGS. 1 and 2 are described. In the short discharge pipe 14A, a longer thin discharge pipe 14B is provided.
The discharge pipe 14B and the movable pipe 14M are thin stainless steel pipes, and a reversible motor (preferably a micromotor) is used to slide the movable pipe 14M in the axial direction (vertical direction) with respect to the discharge pipe 14B. The movable tube 14M is moved up and down by winding or unwinding the cord 64 around the winding drum 62 by driving the 60. Since both the discharge pipe 14B and the movable pipe 14M are thin stainless steel pipes having a thickness of 0.2 to 1 mm, the molten metal M flows immediately after the hot water supply is started, as well as good drainage of hot water and small heat capacity. Temperature rises close to the molten metal temperature,
When the passage of the molten metal is interrupted after the hot water supply is completed, the temperature drops rapidly,
Since the temperature drops rapidly from the molten metal temperature of 50 to 700 ° C. to near normal temperature, the magnesium rapidly passes through the combustion temperature range (temperature range) of magnesium in 1 to 2 seconds, and as a result, the discharge pipe 14B
Oxidation of magnesium adhering to the inner surface of the movable tube 14M is more and less likely to occur.

[0010] The thickness of the stainless steel pipe is 0.2 to 1 mm
The lower limit of 0.2 m
If it is less than m, the pipe itself becomes weak in strength, easily deformed, and the setting such as the height and position with the die-casting sleeve 20 may be out of order.
If the thickness exceeds m, the heat capacity becomes large when the molten metal M passes, and the discharge pipe 14A and the movable pipe 14M do not gradually rise in temperature but must be preheated immediately before hot water supply.

The embodiment shown in FIG. 4 is an embodiment in which the movable tube 14M is not a slide tube as shown in FIGS. 2 and 3, but is a telescopic tube. Select a bellows shape or a material that can be easily bent and the lower end position can move up and down. For the expansion and contraction of the movable tube 14M and the change of the lower end position, the above-described air cylinder and motor can be used, or other power means can be adopted.

As described above, in the magnesium hot water supply apparatus 1 of the present invention, the movable pipe 1 is located below the discharge portion 14T of the hot water supply pipe 10 (specifically, the hot water supply pipe 14 outside the furnace).
Since 4M is provided and the molten metal is discharged after the movable tube 14M is inserted into the inside of the die casting sleeve 20 or the like at the time of supply, oxidation and combustion of molten magnesium can be prevented. Further, in the magnesium hot water supply apparatus provided with the hot water supply pipe of the present invention, the hot water is drained better than in the conventional structure, the dripping after the hot water supply is completed is less, the operation of the die casting piston in the die casting sleeve is insufficient, and the metal of the die casting sleeve is less. Poor mounting on the mold can be prevented. In addition, the injection and combustion of the flame-retardant gas can prevent oxidation and combustion of the molten metal, and the inside of the die-cast sleeve of the die-casting machine is made to have a flame-retardant gas atmosphere.

[0013]

As described above, in the present invention,
Not only can oxidation and combustion of the molten magnesium supplied and discharged be prevented, but also the hot water supply pipe can be desirably drained after the completion of the hot water supply, thereby preventing run-off problems.

[Brief description of the drawings]

FIG. 1 is an overall vertical sectional view of a magnesium water heater according to an embodiment of the present invention.

FIG. 2 is an enlarged longitudinal sectional view of a main part of a hot water supply pipe discharge section according to the embodiment of the present invention.

FIG. 3 is an enlarged longitudinal sectional view of a main part of a hot water supply pipe discharge section according to another embodiment of the present invention.

FIG. 4 is an enlarged vertical sectional view of a main part of a hot water supply pipe discharge section according to another embodiment of the present invention.

FIG. 5 is an overall vertical sectional view of a conventional magnesium water heater.

[Explanation of symbols]

 Reference Signs List 1 magnesium hot water supply device 2 melting pot 2A melting pot flange 3 melting furnace 4 lid (top plate) 5 injection sleeve 6 injection piston 7 suction valve 8 base plate 8a melt passage 8b opening 9 inert gas injection pipe 10 hot water supply pipe 11 injection Cylinder 11a Piston rod 12 Piston rod 13 Shaft coupling 14 Outside hot water supply pipe 14A Discharge pipe 14B Discharge pipe 14M Movable pipe 14P Blind plate 14T Discharge part 15 Stand 16 Hydraulic cylinder 17 Valve rod 18 Heater 19 Check valve 19A Hydraulic cylinder 20 Die-cast sleeve Reference Signs List 21 Die-cast piston 30 Pipe joint 40 Injection nozzle 42 Flameproof gas supply pipe 50 Air cylinder 50a Piston rod 60 Motor 62 Roller cylinder 64 Code M Molten magnesium (molten metal)

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-7-246455 (JP, A) JP-A-7-314111 (JP, A) JP-A-7-16737 (JP, A) 210427 (JP, A) JP-A-5-8017 (JP, A) JP-A-50-133930 (JP, A) JP-A-8-25013 (JP, A) JP-A 8-19848 (JP, A) JP-A-8-10925 (JP, A) JP-A-7-40026 (JP, A) JP-A-5-261512 (JP, A) JP-A-5-33760 (JP, A) JP-A-8-19849 (JP, A) JP-A-7-323358 (JP, A) JP-A-7-314112 (JP, A) JP-A-7-303952 (JP, A) JP-A-7-214271 (JP, A) Kaihei 7-47456 (JP, A) Japanese Utility Model Showa 49-53013 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) B22D 35/00 B22D 1 7/02 B22D 17/30 B22D 39/02

Claims (3)

(57) [Claims] 1. A passage for molten magnesium perforated in a base of a melting furnace, wherein the molten magnesium contained in the melting furnace is pierced in the base by an injection piston sliding inside an injection sleeve fixed to a base plate suspended from a top plate in the melting furnace. In a magnesium hot water supply device that supplies a hot water supply pipe through a hot water supply pipe that communicates with the outside via a hot water supply pipe, a vertical discharge pipe is joined to the hot water supply pipe that rises in an inclined manner, and the discharge pipe is vertically connected to the discharge pipe. A magnesium water heater characterized by joining a movable pipe that can move up and down. 2. The magnesium hot water supply apparatus according to claim 1, wherein the movable pipe is a telescopic pipe. 3. The magnesium hot water supply apparatus according to claim 1, wherein an injection port of a flameproof gas for preventing oxidation and combustion of the molten magnesium flowing down in the discharge pipe is provided at an upper end of the discharge pipe.