JP3882013B2 - Casting water heater - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a water heater of the die casting machine and machine casting machine, and particularly relates to a new water heater capable of preventing the entrainment air generated during hot water supply.
[0002]
[Prior art]
The pouring system in the current die casting machine and mechanical casting machine will be described with reference to FIGS.
FIG. 5 is a diagram for explaining a pouring system using a handwork and a general automatic water heater. The casting apparatus main body includes a fixed die 3 attached to the fixed die plate 1 and a movable die 4 attached to the movable die plate 2. A sleeve 5 and a mold sleeve 6 are formed through the fixed die plate 1 and the fixed mold 3 in order to supply molten metal to the cavity 7 formed on the opposed surfaces of the fixed mold 3 and the movable mold 4. It communicates with the cavity 7 through 6a and the runner 6b. Hot water is supplied to the sleeve 5 by a ladle 9 which is a ladle portion of an apparatus called an automatic water heater, and a molten metal is drawn from a melting furnace (not shown) and is supplied from a hot water outlet 5 a formed in the sleeve 5. The ladle 9 is provided with a ladle at the tip of the robot arm, and is controlled by a control device (not shown) to perform a hot water supply operation into the sleeve. The tip 8 is a piston for pushing the molten metal 10 supplied in the sleeve into the cavity 7.
[0003]
Next, the operation will be explained. The ladle 9 fills the sleeve 5 with about 30% of the molten metal 10, and then pushes the tip 8 to rectify the current with the current divider 6 a and push the molten metal into the cavity 7 from the runner 6 b. The movable die 4 is pressed against the fixed die 3 from the movable die plate 2 side and clamped, and when the metal in the cavity is solidified, the movable die is retracted, and the cast product is taken out.
[0004]
FIG. 6 is a view for explaining an electromagnetic induction pump type pouring system, and the same reference numerals as those in FIG. 5 indicate the same contents.
In this example, hot water is supplied into the sleeve 5 using the electromagnetic induction pump 11. For this purpose, the stalk (pipe) 13 is extended from the sleeve to the holding furnace 12 containing molten metal, and the molten metal is pumped by the electromagnetic induction pump 11. Metal is fed into the sleeve. Then, in the process in which the molten metal in the sleeve is pushed out by the tip 8 and poured into the cavity, when the opening portion of the stalk 13 to the sleeve is closed, the electromagnetic induction pump is turned off and the molten metal in the stalk 13 is removed. It is made to drop into the holding furnace 12. Other configurations are the same as those in FIG.
[0005]
FIG. 7 is a diagram for explaining the in-furnace pressurized pouring system, and the basic configuration is the same as in FIG.
In this example, the inside of the furnace 12 is pressurized from the pressurized gas tank 14, and the molten metal is supplied into the sleeve through the stalk 13 at this pressure. In the process of extruding the molten metal in the sleeve by the tip 8, the pressurization is stopped when the tip opening of the stalk is closed, and the molten metal in the stalk is dropped into the holding furnace 12.
[0006]
[Problems to be solved by the invention]
In such a conventional pouring system, the sleeve to be poured is already filled with air, and in order to fill the molten metal there, the air is entrained with the molten metal and enters the cavity. This phenomenon cannot be prevented, and this causes a defect in a molded product (cast product). If the inside of the sleeve is filled with molten metal so as not to entrain air, the resistance when the molten metal is pushed in by the tip becomes too large, so that pouring takes time, the metal starts to solidify, and the molten metal overflows. At present, the filling rate in the sleeve is at most about 30%. Furthermore, in the conventional pouring system, a high pressure is required to supply the molten metal into the sleeve, and it takes time to push the tip over the entire length of the sleeve, so that the molten metal does not solidify by cooling, High speed operation was necessary.
[0007]
The present invention is for solving the above-mentioned problems, and creates a state in which there is no air or other gas in the sleeve, eliminates entrainment of gas which is a cause of defective casting, and casts at low temperature, low pressure and low speed. It aims to make possible.
[0008]
[Means for Solving the Problems]
The hot water supply device of the casting apparatus of the present invention guides the molten metal into the fixed die plate and the sleeve formed in the fixed mold through the stalk extending from the furnace in which the molten metal is stored, and is attached between the fixed die plate and the movable die plate. In the apparatus for supplying the molten metal into the cavity formed between the fixed mold and the movable mold and communicating with the sleeve,
An injection tip slidable in the sleeve;
A cylinder formed in the movable mold and aligned with the sleeve; an auxiliary tip slidable between the cylinder and the sleeve;
A vacuum device for evacuating the sleeve, cylinder, and cavity;
A servo control mechanism for synchronously operating the injection chip and the auxiliary chip,
The injection tip is a stalk joint port to the sleeve, the auxiliary tip is stopped by abutting the surfaces of both tips at positions where the sleeve and the communication port of the cavity are closed, and then the injection tip is retracted. The molten metal is sucked between the two chips by the negative pressure generated between the two chips when the stalk joint port is opened, and the auxiliary chip and the injection chip are moved to the movable mold side while keeping the molten metal sucked, and the auxiliary When the chip opens the communication port, the molten metal between the two chips is supplied into the cavity by pushing out the injection chip.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below.
FIG. 1 is a view for explaining a pouring system of the present invention, FIG. 2 is an overall view of the apparatus, FIG. 3 is a schematic view of a tip lubricating device, and FIG. 4 is a view for explaining the operation of the pouring system of the present invention. .
In FIG. 1, a sleeve 22 is formed through the fixed mold 20 so that an injection tip 24 driven by a plunger rod 23 can slide in the sleeve. A cylinder 25 is provided in the movable die 21 so as to align with the sleeve 22 and allow the in-die auxiliary tip 27 to slide over the sleeve 22, and an in-die auxiliary tip drive cylinder 26 is provided behind the cylinder 25. Can be driven. A cavity 28 formed between the fixed mold 20 and the movable mold 21 communicates with the sleeve 22 and the cylinder 25 through a runner 29.
[0010]
A stalk 32 extends from the furnace 30 in which a molten metal 31 such as an aluminum alloy, magnesium, zinc alloy, brass, or the like disposed below the mold is housed to the fixed mold 20, and the stalk 32 and the sleeve 22 are formed from an expandable bellows. It is jointed by the Stoke raising / lowering device 34 which becomes. The bellows is lowered when the mold is exchanged, when the stalk is exchanged, and when it is inspected, and is used when the furnace is taken out of the mechanical device. During pouring, the bellows acts as a seal holding with the sleeve. In addition, since it is necessary to perform stalk exchange or the like, the fixed mold 20 can be divided by a double structure to facilitate the exchange work. Since the molten metal passing through the stalk 32 requires a certain melting temperature, a space is formed so that hot air in the furnace 30 is transmitted to the tip, and the heat in the furnace is not used for solidification. Of course, an electric heater can be wound around the outer periphery of the stalk 32 to keep it warm. The joint between the stalk 32 and the sleeve 22 is sealed by a spacer 33. The spacer is made of silicon nitride or a titanium alloy material, and has a structure in which stalk is received by a spherical surface and sealed.
[0011]
As shown in FIG. 2, the drive mechanism of such a hot water supply system is transmitted power by a control panel and a power panel 40, and an injection tip and an in-mold auxiliary tip are driven by an injection mechanism 41, so The molten metal is sucked between the chips. In this state, both chips are moved in the sleeve, and when the space between the chips communicates with the runner 29, the molten metal sucked between the chips is sucked into the cavity by the vacuum in the cavity and the pushing operation of the injection chip 24. Is done. The molten metal poured into the cavity is cast between the molds 20, 21 by clamping the fixed die plate 18 and the movable die plate 19 by the mold clamping mechanism 42, and then the mold 20, by the mold clamping mechanism 42. After separating 21, a push pin (not shown) is operated by the push mechanism 43 to remove the product from the cavity. Further, in the present invention, a vacuum device and a tank 44 are provided, and the molten metal sucked between the injection tip 24 and the in-mold auxiliary tip 28 is further evacuated in the cavity 28, the sleeve 22, and the cylinder 25 during pouring, A slight pressure is applied to the furnace so that it does not fall into the furnace 30 during chip movement or due to other factors. In addition, a pressure increase generating device 45 is provided for applying a high driving force to the injection tip as required. The injection mechanism 41, the mold clamping mechanism 42, the push-out mechanism 43, and the like may be configured to be driven by servo control.
[0012]
As shown in FIG. 3, the lubrication device for the lubrication device for the sleeve and the tip, which is constantly at a high temperature, has a lubricating oil hole 23a formed in the plunger rod 23 to which the tip 24 is attached, and is attached to the rear end of the tip. Lubricating oil is blown out from the hole formed in the ring 24a into the sleeve before the tip moves backward. Similarly, a lubricating oil hole 26a is also formed in the cylinder rod on the side of the in-mold auxiliary tip 27 so that the lubricating oil is blown out from the rear end portion of the tip. In addition, when the mold is opened, the chip and the auxiliary chip may be advanced to the outside of the mold so that the rear end of the chip is positioned on the mold surface, and the lubricating oil is sprayed to retract the chip. . The tips 24 and 27 are cooled by introducing cooling water through cooling passages 23b and 26b formed through rods, respectively.
[0013]
Next, the operation of the system of the present invention will be described with reference to FIG.
When the open fixed mold and the movable mold are combined, the tips of the in-mold auxiliary chip 27 and the injection chip 24 are projected from the mold surface to the outside, and the surfaces of both chips are butted together when the mold is clamped. As shown in FIG. 4 (a), the auxiliary tip 27 at the tip of the in-mold auxiliary tip drive cylinder 25 is advanced into the sleeve 22, and the injection tip is retracted as a synchronous operation, and both the injection tips are closed at a predetermined position where the runner opening is closed. Stop the tip. This stop position is the hot water supply start position.
[0014]
As shown in FIG. 4B, when the hot water supply is started, the inside of the sleeve 22, the cylinder 25, and the cavity 28 are evacuated by the vacuum device 44. In some cases, an inert gas or the like is added to prevent oxidation of the aluminum metal as necessary. Next, when the injection tip 24 is slowly retracted, the space in the sleeve formed between the in-mold auxiliary tip and the injection tip becomes a vacuum, and when the injection tip 24 is retracted to open the joint port of the stalk 32, The molten metal in the furnace is sucked into the space between both chips through the stalk due to the negative pressure, and the hot water supply operation is instantaneously performed. The reverse stroke of the injection tip 24 is set according to the hot water supply amount. While holding the molten metal filled between the auxiliary tip 27 and the injection tip 24, the injection tip 24 moves forward, and the auxiliary tip 27 moves backward as a synchronizing operation. These tuning operations are driven and controlled by the injection mechanism 41. At this time, the inside of the furnace is slightly pressurized to the tank 44 until the injection chip 24 closes the joint port of the stalk 32 so that the molten metal held in the space between the two chips does not flow back into the furnace 30. When both chips move toward the movable mold 21, the evacuation in the cavity, sleeve, and cylinder stops.
[0015]
Next, as shown in FIG. 4C, when the in-mold auxiliary tip 27 comes to the end of the runner, it is stopped and driven by the vacuum in the cavity 28 by driving the injection tip 24 and held between the two tips. The molten metal is sucked into the cavity. At this time, the movement of the injection tip 24 may be accelerated in order to speed up pouring into the cavity. After the pouring is completed, the molds 20 and 21 are opened after being molded and cooled. At this time, the injection tip 24 is moved to push the solidified metal into the sleeve, and then stopped. The auxiliary chip and the injection chip are preferably driven in synchronism by electric servo or hydraulic servo control, but general hydraulic control is also possible.
[0016]
As described above, the molten metal in the furnace is sucked into the vacuum space formed between the chips using the auxiliary chip and the injection chip, so that the pouring operation can be completed without involving any air. In addition, since the molten metal is not poured through a long sleeve as in the prior art, the temperature of the molten metal does not decrease, and the high-speed and high-pressure operation that has been required in conventional casting machines is unnecessary. Casting is possible, and it is possible to cast parts that could only be produced by special machines that were previously impossible. For example, in the case of aluminum or the like, it is conventionally heated to about 700 ° C., and at this temperature, it is easily oxidized and the mold is damaged. Casting can be performed at a temperature of, for example, about 580 ° C. in which aluminum exhibits a liquid phase, there is no reaction with iron, and the mold is not damaged, so that the mold life can be extended. The chip operation of the present invention can be performed at a low speed and has a basic operation of about 0.01 m / s to 1.0 m / s, but other than this, generally performed is about 0.3 m / s to 2 m / s. But it is possible. That is, in the present invention, low speed and low pressure are possible, as well as high speed and high pressure.
[0017]
In addition, since the gate and the gate area, which have been fixed in the past, can change the retracted position of the auxiliary tip, the sectional area can be changed, and the gate speed can be freely changed. Therefore, even if the mold changes and the volume of the cavity changes, the position of the in-mold auxiliary chip can be changed freely. In addition, it is possible to eliminate the runner that has been conventionally required for the product, or to make the layout sufficiently shorter than before.
[0018]
【The invention's effect】
As described above, the pouring system of the present invention can completely eliminate factors caused by air or gas in the sleeve, such as gas entrainment, which is a cause of defective castings, which has been a problem in the past, and can reduce the defect rate. Can be realized. Conventionally, since the gas in the sleeve cannot be removed by any method, various methods such as vacuum pouring, local pressurization GF method, and other pouring methods have been studied, but a gas-free space is created as in the present invention. There is no pouring system. In addition, pouring and casting are the basic operations at low speed, but it is possible to form products with much better quality than conventional low-speed casting methods, and it is possible to eliminate the need for a pressure booster that has been essential in the past. / Hydraulic servo control enables more reliable hot water supply and molding control. Moreover, it is possible to pour alloys such as magnesium, which has been considered difficult for hot water supply. In addition, the working environment of the conventional die casting foundries has been improved, making it possible to create a clean foundry, making it possible to supply hot water that was impossible with molten metal, and the product range will be significantly higher than the current market. . In addition, since molding at high pressure is not required, the mold clamping mechanism is greatly reduced, and a doubled size (with a castable area) is possible from a cast product of the current machine size. As a result, seizure, which is one of the causes of troubles in the mold, is reduced, and the mold life can be extended.
[Brief description of the drawings]
FIG. 1 is a diagram for explaining a pouring device of the present invention.
FIG. 2 is an overall view of the apparatus.
FIG. 3 is a schematic view of a chip lubricating device.
FIG. 4 is a diagram for explaining the operation of the pouring device of the present invention.
FIG. 5 is a diagram for explaining a conventional pouring device .
FIG. 6 is a diagram for explaining a conventional pouring device .
FIG. 7 is a diagram for explaining a conventional pouring device .
[Explanation of symbols]
18 ... fixed die plate, 19 ... movable die plate, 20 ... fixed mold, 21 ... movable mold, 22 ... sleeve, 23 ... plunger rod, 24 ... injection tip, 25 ... cylinder, 26 ... in-mold auxiliary tip drive cylinder, 27 ... In-mold auxiliary chip, 28 ... Cavity, 29 ... Runner, 30 ... Furnace, 32 ... Stoke, 33 ... Spacer, 34 ... Stoke lifting device, 40 ... Control panel and power panel, 41 ... Injection mechanism, 42 ... Clamping Mechanism 43 ... Extrusion mechanism 44 ... Vacuum device and tank 45 ... Pressure increase generator

Claims (4)

The molten metal is introduced into the fixed die plate and the sleeve formed in the fixed die through the stalk extending from the furnace in which the molten metal is stored, and is formed between the fixed die and the movable die attached between the fixed die plate and the movable die plate. an apparatus for supplying hot water to the molten metal in the cavity communicating with the sleeve,
An injection tip slidable in the sleeve;
A cylinder formed in the movable mold and aligned with the sleeve; an auxiliary tip slidable between the cylinder and the sleeve;
A vacuum device for evacuating the sleeve, cylinder, and cavity;
A servo control mechanism for synchronously operating the injection chip and the auxiliary chip,
The injection tip is a stalk joint port to the sleeve, and the auxiliary tip is stopped by abutting the surfaces of both tips at positions where the sleeve and the communication port of the cavity are closed, and then the injection tip is retracted. When the stalk joint port is opened, the molten metal is sucked between the two chips by the negative pressure generated between the two chips, and the auxiliary chip and the injection chip are moved to the movable mold side while keeping the molten metal sucked, and the auxiliary tip when opening the communication port, the water heater of the casting apparatus, characterized in that the hot water supply of molten metal between the two chips in the cavity by the push-out operation of the injection tip. The hot water supply apparatus for a casting apparatus according to claim 1, wherein a space communicating with a furnace for transmitting hot air in the furnace is provided around the stalk. The hot water supply apparatus for a casting apparatus according to claim 1, further comprising a pressurizing means for pressurizing the inside of the furnace. The hot water supply apparatus for a casting apparatus according to claim 1, wherein the retreat stroke of the injection tip is set according to the amount of hot water supply.

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