KR20150076415A

KR20150076415A - Die casting device and die casting method using molten metal comprising magnesium-based materials

Info

Publication number: KR20150076415A
Application number: KR1020130164532A
Authority: KR
Inventors: 박대규
Original assignee: 재단법인 포항산업과학연구원
Priority date: 2013-12-26
Filing date: 2013-12-26
Publication date: 2015-07-07

Abstract

A die casting apparatus using a molten metal containing a magnesium-based material according to an embodiment of the present invention includes a stationary mold having a first core and a second core coupled to the first core to form a cavity into which a molten metal containing a magnesium- An ejecting part for separating the molded article formed by the cavity from the first core and a housing provided on the fixed mold for forming a moving space of the ejecting part, A pressurizing unit for injecting the molten metal into the cavity, a vacuum pump for reducing the pressure in the cavity and the housing, and a heating unit for heating the first core and the second core.

Description

TECHNICAL FIELD [0001] The present invention relates to a die casting apparatus and a die casting method using a melt containing a magnesium-based material, and a die casting method and a die casting method using a melt containing a magnesium-

The present invention relates to a die casting apparatus and a die casting method using a melt containing a magnesium-based material.

Generally, a die casting apparatus is a precision casting apparatus that injects molten metal (molten metal) into a cavity of a mold that has been processed into a desired shape to produce the same product as the cavity of the mold. The die casting apparatus is equipped with a fixed mold and a movable mold. When the fixed mold and the movable mold are combined, a cavity forming the shape of the product is formed, and a molten metal is injected into the cavity to form a product. Related prior arts are Korean Patent Laid-Open Publication No. 1995-0016992 (published on July 20, 1995, entitled " Magnesium Casting Production Apparatus "). However, such conventional die casting technology has a problem in that when the die casting is carried out, the thickness of the product becomes thick and the finished product becomes poor.

The present invention relates to a magnesium-based material capable of producing a thin-walled thin-walled product, preventing oxidation of the magnesium-based material, and improving the quality of the product when casting die casting using a magnesium- And a die-casting method using the molten metal.

The die casting apparatus using the molten metal containing magnesium based material according to the embodiment of the present invention interrupts the heating temperature of the heat generating unit so that the first core and the second core have a predetermined first temperature range, And a temperature controller for controlling the melting temperature of the molten metal so as to have the predetermined second temperature range.

The pressurization unit may further include a speed control unit for interrupting the movement speed of the molten metal so that the molten metal has a predetermined injection rate range.

The fixed mold and the movable mold may further include a cooler for cooling the molten metal injected into the cavity so that the molded product is molded.

A sealing member may be provided between the first core and the second core to seal the cavity.

The ejecting portion may include a lift portion movably provided inside the housing, an ejecting shaft portion provided in the lift portion to pass through the second core, and an elevation driving portion moving the elevation portion.

A sealing member may be provided between the housing and the elevating unit to seal the inside of the housing.

The cavity is divided into a plurality of main flow paths for branching the molten metal injected through the pressurizing unit and a plurality of main flow paths which are communicated with each other with a thickness equal to or smaller than that of the main flow path, A plurality of injection gates having a thickness smaller than that of the auxiliary transfer path and for branching the molten metal in the auxiliary transfer path; and a heater having a thickness larger than that of the injection gate and smaller than or equal to the thickness of the auxiliary transfer path, And a plurality of vacuum gates branched from the molding part and connected to the vacuum pump, wherein the ejecting part includes a plurality of vacuum gates, And may be protruded from at least one of the vacuum gates.

The predetermined first temperature range is 200 ° C to 250 ° C, the predetermined second temperature range is 650 ° C to 700 ° C, and the predetermined infusion rate range may be 2m / s to 4m / s.

The die casting method using a molten metal containing a magnesium-based material according to an embodiment of the present invention is a method of combining a first core of a stationary mold and a second core of a movable mold so as to form a cavity into which molten metal containing a magnesium- A core heating step of heating the first core and the second core so as to have a predetermined first temperature range; a molten metal heating step of heating the molten metal to have a predetermined second temperature range; A vacuum step including a first vacuum step of reducing the pressure of the cavity and a second vacuum step of depressurizing the interior of the housing provided in the stationary mold; and a step of applying a vacuum to the cavity, And a molten metal injection step of injecting the heated molten metal.

The die casting method using a molten metal containing a magnesium-based material according to an embodiment of the present invention may further include a core cooling step of cooling the first core and the second core to coagulate the molten metal injected into the cavity have.

The die casting method using a molten metal containing a magnesium-based material according to an embodiment of the present invention is characterized in that, when the molten metal solidifies, a mold is separated from the stationary mold so that the first core and the second core are separated from each other. And a step of separating the molded article from the first core in accordance with the solidification of the molten metal.

The thickness of the product produced through the molded article may be from 1.5 mm to 5 mm.

The vacuum pump can maintain the pressure of the cavity at 10 mbar to 50 mbar.

According to the embodiment of the present invention, it is possible to manufacture a thin-walled thin-walled product when casting die casting using a magnesium-containing material, prevent oxidation of the magnesium-based material, .

1 is a view schematically showing a die casting apparatus according to an embodiment of the present invention.
2 is a view schematically showing an open state of a die casting apparatus according to an embodiment of the present invention.
3 is a plan view schematically showing the shape of a cavity in a die casting apparatus according to an embodiment of the present invention.
4 is a cross-sectional view schematically showing a shape of a cavity in a die casting apparatus according to an embodiment of the present invention.
5 is a photograph showing a product cast according to an embodiment of the present invention.
6 is a flowchart showing a die casting method according to an embodiment of the present invention.
FIG. 7 is a view showing an injection state of a molten metal over time in a die casting apparatus according to an embodiment of the present invention. FIG.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, which will be readily apparent to those skilled in the art to which the present invention pertains. The present invention may be embodied in many different forms and is not limited to the embodiments described herein.

In addition, in the various embodiments, elements having the same configuration are denoted by the same reference numerals, and only other configurations will be described in the other embodiments.

The drawings are schematic and illustrate that they are not drawn to scale. The relative dimensions and ratios of the parts in the figures are shown exaggerated or reduced in size for clarity and convenience in the figures, and any dimensions are merely illustrative and not restrictive. Also, to the same structure, element, or component appearing in more than one of the figures, the same reference numerals are used to denote similar features. When referring to a portion as being "on" or "on" another portion, it may be directly on the other portion or may be accompanied by another portion therebetween.

The embodiments of the present invention specifically illustrate one embodiment of the present invention. As a result, various variations of the illustration are expected. Thus, the embodiment is not limited to any particular form of the depicted area, but includes modifications of the form, for example, by manufacture.

Hereinafter, a die casting apparatus and a die casting method using a melt containing a magnesium-based material according to an embodiment of the present invention will be described with reference to the accompanying drawings.

In the present invention, the molten metal is a molten material containing a magnesium-based material, and includes a material containing magnesium or a magnesium alloy in a molten state.

In the present invention, the cavity C refers to a space to which the molten metal is transferred by the engagement of the first core 13 and the second core 23, and the molded product M is a space in which the molten metal injected into the cavity C is solidified Refers to a state in which an unnecessary portion is removed from the molded product M and the product is a portion where the molten metal solidifies in the molded portion C4 of the cavity C. [

FIG. 1 is a view schematically showing a die casting apparatus according to an embodiment of the present invention, FIG. 2 is a view schematically showing an open state of a die casting apparatus according to an embodiment of the present invention, and FIG. FIG. 4 is a cross-sectional view schematically showing the shape of a cavity in a die casting apparatus according to an embodiment of the present invention, and FIG. 5 is a cross-sectional view schematically showing the shape of a cavity Fig.

1 to 5, a die casting apparatus according to an embodiment of the present invention prevents oxidation of a magnesium-based material when casting die casting using a melt containing a magnesium-based material, , And thin-walled thin-walled products can be manufactured.

The die casting apparatus according to an embodiment of the present invention includes a stationary mold 10, a movable mold 20, an ejector 30, a pressing unit 40, a vacuum pump 50, a heat generating unit 60, And a temperature control unit (80).

The stationary mold 10 is coupled with the movable mold 20 to form a cavity C. The first core 13 is provided inside.

The stationary mold 10 can be divided into a stationary main body 11 and a first core 13 provided inside the stationary main body 11. The first core 13 is detachably attached to the fixed body 11 according to the shape of the cavity C.

The movable mold 20 is movably coupled to the stationary mold 10 to form a cavity C and a second core 23 coupled to the first core 13 is provided therein.

The movable mold 20 can be divided into a moving body 21 and a second core 23 provided inside the moving body 21. The second core 23 is removably attached to the moving body 21 according to the shape of the cavity C.

The stationary mold 10 and the movable mold 20 may further include a cooler 70.

The cooler 70 cools the molten metal injected into the cavity C so that the molten metal solidifies to form the molded product M in the shape of the cavity C. The cooler 70 can cool the first core 13 and the second core 23 so that the molten metal injected into the cavity C can be uniformly solidified.

By using cooling oil when cooling the first core 13 and the second core 23 through the cooler 70, it is possible to prevent the explosion due to the exothermic reaction due to the contact between the molten metal containing the magnesium- can do.

Here, the stationary mold 10 and the movable mold 20 may be provided with a seventh band mold B for forming a seventh band portion C7.

The molten metal containing the magnesium-based material is stably injected and solidified into the cavity C formed by the combination of the first core 13 and the second core 23 through the seventh vent mold B, It is prevented from flowing into the pump 50, and a stable molded product M can be molded.

Here, a sealing member Sa is provided between the first core 13 and the second core 23. The sealing member Sa allows the cavity C formed by the first core 13 and the second core 23 to be sealed.

The provision of the sealing member Sa prevents external air from flowing between the first core 13 and the second core 23 and can stably maintain the reduced pressure state of the cavity C. [

Further, since the sealing member Sa is provided, it is possible to prevent the molten metal containing the magnesium-based material injected into the cavity C from being oxidized and oxidized.

Here, the cavity C includes a main moving path C1, a secondary moving path C2, an injection gate C3, a forming portion C4, and a vacuum gate C5.

The main passage (C1) branches the molten metal injected through the pressurizing unit (40) into a plurality of molten metal. In the embodiment of the present invention, the main travel path C1 is divided into four in the pressurizing unit 40. [

The auxiliary travel path C2 branches the molten metal that is moved through the main travel path C1 into a plurality of pieces. A plurality of branching auxiliary paths C2 are connected so that their ends are mutually communicated. The auxiliary travel path C2 has a thickness equal to or smaller than the main travel path C1.

The injection gate C3 branches the molten metal in the auxiliary transfer path C2. In one embodiment of the present invention, the injection gate C3 branches at twelve apart from each other in the auxiliary path C2.

The injection gate C3 has a smaller thickness than the auxiliary movement path C2.

The forming portion C4 is connected to the injection gate C3 so as to communicate with each other, and is formed apart from the auxiliary transfer path C2. As the molten metal to be injected solidifies in the molding part C4, the molding part C4 exhibits a shape.

The forming portion C4 is larger than the injection gate C3 and has a thickness equal to or smaller than the auxiliary movement path C2.

The vacuum gate C5 is branched into a plurality of parts in the molding part C4 so as to be connected to the vacuum pump 50. [ The vacuum gate C5 is capable of branching the molten metal injected into the molding section C4.

In one embodiment of the present invention, the vacuum gates C5 are branched from each other in the forming portion C4.

In addition, the cavity C may further include a suction path C6 and a seventh band portion C7.

The suction path C6 connects the vacuum gates C5 so as to communicate with each other, and a plurality of the vacuum gates C5 are branched toward each other toward the seventh band portion C7. The suction path C6 can branch the molten metal to be injected into the vacuum gate C5.

In an embodiment of the present invention, six suction paths C6 branch off from each other along the periphery of the forming portion C4.

The seventh band portion C7 is formed by the seventh band mold B with the combination of the fixed mold and the movable mold so that the suction path C6 and the vacuum pump 50 are communicated with each other.

The seventh band portion C7 prevents the molten metal injected into the suction path C6 from being transmitted to the vacuum pump 50. [ When the molten metal is injected into the seventh band portion C7, the molten metal is prevented from solidifying in the seventh band portion C7 and being transmitted to the vacuum pump 50. [

The ejector 30 separates the molded product M from the stationary mold 10. The ejector 30 includes an ejecting portion 31 and a housing 37.

The ejecting portion 31 separates the molded product M molded in the cavity C from the first core 13 and the housing 37 is fixed to the fixed mold 10 so as to form a moving space of the ejecting portion 31 Respectively.

Here, the ejecting portion 31 includes a lifting portion 34, an ejecting shaft portion 32, and a lifting and driving portion 36.

The elevating portion (34) is provided movably inside the housing (37).

The tenter shaft portion 32 is provided in the elevation portion 34 so as to pass through the second core 23. The cavity C and the inside of the housing 37 are communicated with each other as the ejecting shaft portion 32 is formed.

The lifting drive part 36 moves the lifting part 34 and the lifting drive part 36 includes the lifting piston 39 and the lifting cylinder 38. [

The lifting piston 39 is coupled to the lifting portion 34 through the housing 37. The lifting piston 39 is supported by the housing 37 and is movable in the longitudinal direction of the ejecting shaft portion 32.

The lifting cylinder 38 reciprocates the lifting piston 39 by an applied power source.

When the power is applied to the lifting cylinder 38 in the ejecting portion 31, the lifting piston 39 is reciprocated by the lifting cylinder 38, so that the lifting portion 34 is moved in the housing 37 Is moved in the longitudinal direction of the ejecting shaft portion (32), and the end portion of the ejecting shaft portion (32) can protrude from the cavity (C). Accordingly, the molded product M supported at the end of the ejecting shaft portion 32 can be separated from the first core 13.

In particular, the end of the ejecting shaft portion 32 of the ejecting portion 31 can protrude from at least one of the injection gate C3 and the vacuum gate C5. The molded product M to be molded in the cavity C can be stably separated from the stationary mold 10 and the end trace of the ejecting shaft portion 32 can be prevented from appearing on the outer surface of the product. In addition, it smoothes the outer surface of the product, makes the appearance of the product look good, and simplifies the surface treatment of the product.

Here, the ejector 30 is provided with the sealing member Sb. The sealing member Sb closes the interior of the housing 37 between the housing 37 and the elevation portion 34. The sealing member Sb is provided to prevent the outside air from flowing into the space between the housing 37 and the elevation portion 34. [

Since the inside of the housing 37 is communicated with the cavity C by the ejecting shaft portion 32, the inside of the housing 37 through the sealing member Sb is sealed, whereby the decompressed state of the cavity C can be stably .

In addition, it is possible to prevent the molten metal containing the magnesium-based material injected into the cavity C from being combined with oxygen and being corroded.

At this time, in order to improve the sealing force between the housing 37 and the elevation part 34, the housing 37 may be provided with a protrusion 37a. The contact protrusion 37a protrudes from the housing 37 to support the lifting piston 39 and a sealing member Sb is provided between the contact protrusion 37a and the lifting part 34. [

The pressurizing unit (40) injects molten metal into the cavity (C). The pressurizing unit 40 includes a pressurizing drive unit 41, a plunger 43, a speed control unit 45, and an injection path 47.

The pressurizing driving unit 41 generates a pressing force for injecting the molten metal.

The plunger 43 moves the molten metal to the cavity C by the pressing force of the pressure driver 41.

The speed control unit 45 interrupts the movement speed of the molten metal so that the molten metal has a predetermined injection rate range. The movement speed of the molten metal can be controlled through the movement speed of the plunger 43. [

The injection path 47 forms a path of movement of the plunger 43 and the molten metal injected into the cavity C. The plunger 43 is inserted into the injection path 47 so that the plunger 43 moves the molten metal injected into the moving mold surface injection path 47 along the injection path 47 stably by the pressing force of the pressure drive section 41. [ ㈎ Can be injected. Here, the predetermined injection rate range is set to 2 m / s to 4 m / s or less.

More specifically, the predetermined injection rate range is set to 2 m / s or more and 2 m / s or less when the speed is low. The predetermined injection rate range is set to 3.5 m / s or more and 4 m / s or less when the speed is high. The predetermined injection rate range is set to be 2.5 m / s or more and 3.5 m / s or less.

As described above, in the predetermined injection rate range, the molten metal injected into the cavity C through the injection path 47 is stably injected into the thinner injection gate C3 and the molding portion C4, It is possible to prevent the product from being solidified or deformed to take out the product, or to prevent the product from being defective.

However, when the molten metal is smaller than the lower limit value in the above-described injection speed range, the molten metal may solidify in the cavity C before reaching the thin injection gate C3 or the molding portion C4, It can be caused.

If the molten metal is larger than the upper limit in the above-described injection speed range, it is difficult to intermittently control the temperature of the molten metal to be injected, and the molten metal is not stably injected into the cavity C, Or may cause deformation of the product or deterioration of the product.

At this time, a blast furnace (90) for supplying molten metal is connected to the pressurizing unit (40). The molten metal is stored in the furnace 90 and supplies the molten metal to the pressurizing unit 40. The supply path 91 purchased in the blast furnace 90 is connected to the injection path 47 of the pressurizing unit 40 to transfer the molten metal stored in the blast furnace 90 to the injection path 47 of the pressurizing unit 40 Thereby forming a transport path. At this time, by interrupting the temperature of the molten metal transferred to the injection path 47 of the pressurizing unit 40, the molten metal is stably injected into the cavity C.

The vacuum pump 50 reduces the pressure inside the cavity 50 and the housing 50. Since the sealing member Sa and the sealing member Sb are provided to prevent the external air from flowing into the cavity C when the cavity C is depressurized and the reduced pressure state of the cavity C can be stably maintained .

Particularly, the pressure of the cavity C, which is reduced through the vacuum pump 50, is made to be 50 mbar or less. More specifically, the pressure of the cavity (C) is reduced to 35 mbar or less.

As described above, the pressure of the depressurized cavity C can smoothly transfer the material to be injected into the cavity C, and bubbles can be prevented from being generated in the molten metal to be injected.

However, when the pressure of the cavity C is larger than the upper limit, it is difficult to control the injection rate of the molten metal through the pressurizing unit 40, and the molten metal reaches the injection gate C3 or the molding portion C4 Before being solidified in the cavity (C). This may result in unformed products, deformation of products, or defective products.

The heat generating unit 60 is provided in the stationary mold 10 and the movable mold 20 to heat the first core 13 and the second core 23. The heating unit heats the first core 13 and the second core 23 so that the molten metal can be stably charged in the cavity C.

The temperature control unit 80 interrupts the heating temperature at which the heat generating unit 60 heats the first core 13 and the second core 23 and interrupts the melting temperature of the molten metal.

First, the temperature control unit 80 controls the heating temperature of the heat generating unit 60 so that the first core 13 and the second core 23 have a predetermined first temperature range. Here, the predetermined first temperature range is set to be not less than 200 degrees Celsius and not more than 250 degrees Celsius.

More specifically, the predetermined first temperature range is at least 200 degrees Celsius and not more than 230 degrees Celsius. Also, the predetermined first temperature range is set to be 220 deg. C or more and 250 deg. C or less. Also, the predetermined first temperature range is set to be 220 deg. C or more and 230 deg. C or less.

Further, the temperature control unit 80 controls the melting temperature of the molten metal so that the molten metal has a predetermined second temperature range. Here, the predetermined second temperature range is set to be not less than 650 degrees Celsius and not more than 700 degrees Celsius.

More specifically, the predetermined second temperature range is at least 650 degrees Celsius and less than 690 degrees Celsius. In addition, the predetermined second temperature range is set to be not less than 670 degrees centigrade and not more than 700 degrees centigrade. In addition, the predetermined first temperature range is set to be 670 degrees centigrade or more and 690 degrees centigrade or less.

The molten metal can be stably charged in the cavity C in a predetermined first temperature range and a predetermined second temperature range as described above.

The molten metal injected into the cavity C through the injection path 47 is stably injected into the thin injection gate C3 and the molding part C4 and is prevented from solidifying during the injection process, It is possible to prevent unformed or deformation of the product or defective product.

However, if the molten metal is smaller than the lower limit in the first temperature range and the second temperature range, the molten metal may solidify in the cavity C before reaching the thin injection gate C3 or the forming portion C4, Which may cause the molding of the product.

If the temperature is higher than the upper limit in the first temperature range and the second temperature range, it is difficult to control the temperature of the molten metal to be injected, and since the molten metal is not stably injected into the cavity C, Bubbles may be generated, resulting in unformed products, deformation of products, or defective products.

Hereinafter, a die casting method according to an embodiment of the present invention will be described.

FIG. 6 is a flowchart showing a die casting method according to an embodiment of the present invention, and FIG. 7 is a view showing a state of injection of molten metal with time in a die casting apparatus according to an embodiment of the present invention.

6 and 7, a die casting method according to an embodiment of the present invention includes a mold closing step S1, a core heating step S2, a molten metal heating step S3, a vacuum step S4, , And a molten metal injection step (S5).

The mold closing step S1 is a step of pressing the first core 13 of the stationary mold 10 and the second core 23 of the movable mold 20 so as to form the cavity C into which the molten metal containing the magnesium- .

The core heating step S2 heats the first core 13 and the second core 23 to have a predetermined first temperature range. In the core heating step S2, the first core 13 and the second core 23 are heated through the heat generating unit 60, and the temperature of the first core 13 and the temperature of the second core 13, (23) to a predetermined first temperature range. Here, the predetermined first temperature range is not less than 200 degrees Celsius and not more than 250 degrees Celsius.

Further, the temperature control unit 80 controls the melting temperature of the molten metal so that the molten metal has a predetermined second temperature range. Here, the predetermined second temperature range is set to be not more than 700 degrees Celsius above 650 degrees Celsius.

If the temperature is higher than the upper limit in the first temperature range and the second temperature range, it is difficult to control the temperature of the molten metal to be injected, and the molten metal is not stably injected into the cavity C, Or bubbles may be generated in the product, or the product may be deformed or deformed.

The vacuum step S4 depressurizes the interior of the cavity C and the housing 37 to stably maintain the depressurized state of the cavity C. [

The vacuum step S4 includes a first vacuum step S4-1 for reducing the pressure of the cavity C and a second vacuum step S4-2 for reducing the pressure of the interior of the housing 37 provided in the stationary mold 10, .

Particularly, the pressure of the depressurized cavity C through the vacuum step S4 is made to be 50 mbar or less. More specifically, the pressure of the cavity (C) is reduced to 35 mbar or less.

As described above, the pressure of the depressurized cavity C makes it possible to smoothly transfer the molten metal injected into the cavity C, and to prevent bubbles from being generated in the molten metal being injected.

However, when the pressure of the cavity C is larger than the upper limit, it is difficult to control the injection rate of the molten metal through the pressurizing unit 40, and the molten metal reaches the injection gate C3 or the molding portion C4 Before being solidified in the cavity (C). As a result, the product may be unformed, dehydrated, or defective.

The molten metal injection step S5 injects the heated molten metal into the depressurized cavity C through a vacuum step S4 so as to have a predetermined injection rate range.

The molten metal injection step S5 injects the molten metal in the injection path 47 into the cavity C through the pressurizing unit 40. [ The molten metal injection step S5 injects the molten metal in the injection path 47 into the cavity C through the pressurizing unit 40. [

More specifically, the predetermined injection rate range is set to 2 m / s or more and 2.5 m / s or less when the speed is low. The predetermined injection rate range is set to 3.5 m / s or more and 4 m / s or less when the speed is high. The predetermined injection rate range is set to be 2.5 m / s or more and 3.5 m / s or less.

As described above, the molten metal injected into the cavity C through the injection path 47 is stably injected into the thinner injection gate C3 and the molding part C4 at a predetermined injection speed range, It is possible to prevent solidification of the product, prevent deformation of the product, dehydration of the product, or defective product.

However, if the molten metal is smaller than the lower limit value in the above-described injection speed range, the molten metal may solidify in the cavity C before reaching the thin injection gate C3 or the molding portion C4, It can be a cause.

If the molten metal is larger than the upper limit in the above-described injection speed range, it is difficult to intermittently control the temperature of the molten metal to be injected, and the molten metal is not stably injected into the cavity C, And may cause deformation of the product or deformation of the product.

As shown in FIG. 7, the temperature of the molten metal injected into the cavity C with time elapses in the molten metal injecting step (S5), the temperature of the molten metal becomes lower toward the red color on the basis of the green part, The temperature of the molten metal increases.

The molten metal supplied from the pressurizing unit 40 is branched to the main moving path c1 as the time t1 elapses. The ladle branched to the main travel path C1 branches to a part of the auxiliary travel path C2 as the time t2 elapses. As the time of t3 elapses, the molten metal is branched into the entire auxiliary traveling path C2 and a part of the injection gate C3.

As described above, it can be seen that the molten metal supplied through the pressurizing unit 40 is evenly distributed to the entirety of the auxiliary traveling path C2 as the time t3 elapses under the above-described conditions, whereby the molten metal is stably injected into the cavity C. .

Further, as the time of t4 elapses, the molten metal is stably injected into the forming portion C4 through the injection gate C3.

Then, as time passes t5, the molten metal is injected into the suction path C6 via the vacuum gate C5, and the temperature of the molten metal is lowered. In one embodiment of the present invention, the time t5 is about 0.07 seconds.

The die casting method according to an embodiment of the present invention further includes a core cooling step (S6).

The core cooling step S6 cools the first core 13 and the second core 23 so that the molten metal injected into the cavity C solidifies. The core cooling step S6 can cool the first core 13 and the second core 23 through the cooler 70 provided in the stationary mold 10 and the movable mold 20. [

The die casting method according to an embodiment of the present invention further includes a mold separating step S7 and a molded article separating step S8.

In the mold separation step S7, when the molten metal solidifies through the core cooling step S6, the movable mold 20 is separated from the process mold 10 such that the first core 13 and the second core 23 are separated from each other .

The molded article separation step (S8) separates the molded article (M) molded from the first core (13) in accordance with solidification of the molten metal.

In the molded article separating step S8, the end portion of the ejecting shaft portion 32 protrudes from at least one of the injection gate C3 and the vacuum gate C5 so that the molded article M can be stably separated from the process mold 10 have.

Further, it is possible to prevent the appearance of the end portion of the ejecting shaft portion 32 from appearing on the outer surface of the product, to smooth the appearance of the product, to make the appearance of the product look good, and to simplify the surface treatment of the product.

As the molten metal injected into the cavity C solidifies, the molded product M is produced. The molded product (M) solidified in the molding part (C4) becomes a product. The product to be molded here is manufactured to a thickness of more than 1.5 mm and less than 5 mm.

More specifically, the product to be molded is manufactured to a thickness of more than 1.5 mm and less than 3 mm. In addition, the product to be molded is manufactured to a thickness of 2 mm or more and 5 mm or less. In addition, the product to be molded is manufactured to a thickness of 5 mm or more and 3 mm or less.

Thus, it is possible to stably produce a thin-walled product having the above-described thickness through a predetermined first temperature range, a predetermined second temperature range and a predetermined infusion rate range.

However, when the thickness of the product is smaller than the lower limit, the molten metal injected into the cavity C can be solidified in the cavity C before reaching the thin injection gate C3 or the molding portion C4, It may cause the molding of the product.

When the thickness of the product is larger than the upper limit of the thickness of the product, the molten metal is not stably injected into the cavity (C), so that bubbles are generated in the molten metal injected into the cavity (C) . &Lt; / RTI >

Although the die casting apparatus and the die casting method according to the embodiment of the present invention have been described by taking the automotive window molding as an example, the present invention is not limited thereto and can be applied to thin-walled thin products.

As described above, according to the embodiment of the present invention, when die casting is performed using a molten metal containing a magnesium-based material, it is possible to manufacture a thin-walled thin product, prevent oxidation of the magnesium- The perfection can be improved.

Further, when the molten metal is injected, by controlling the temperature of the molten metal, the temperature of the stationary mold, the temperature of the movable mold, and the injection speed of the molten metal, it is possible to prevent the molten metal from being solidified during the injection process, It is possible to prevent deformation.

While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made therein without departing from the spirit and scope of the following claims. Those who are engaged in the technology field will understand easily. Accordingly, the true scope of protection of the present invention should be defined by the claims.

10: stationary mold 11: fixed body
13: first core 20: moving mold
21: moving body 23: second core
30: ejector 31: ejecting portion
32: ejecting shaft portion 34: elevating portion
36: a coaxial drive unit 37: a housing
37a: tight contact portion 38: lift cylinder
39: lifting piston 40: pressure unit
41: pressure drive unit 43: plunger
45: Speed control unit 47:
50: Vacuum pump 60: Heating unit
70: cooler 80: temperature controller
90: furnace 91: supply path
Sa: sealing member Sb: sealing member
B: Seven-band mold C: Cavity
C1: main travel route C2: auxiliary travel route
C3: Injection gate C4: Molded part
C5: Vacuum gate C6:
C7: Chip band M: Molded product
S1: mold adhesion step S2: core heating step
S3: heating the molten metal S4: vacuum stage
S4-1: first oscillation step S4-2: second vacuum step
S5: Molten metal injection step S6: Core cooling step
S7: mold separation step S8: molded article separation step
R: Roller

Claims

A stationary die provided with a first core;
A movable mold having a second core coupled with the first core to form a cavity into which a molten metal containing a magnesium-based material is injected;
An ejector including an ejecting portion for separating the molded article formed by the cavity from the first core, and a housing provided in the stationary mold to form a moving space of the ejecting portion;
A pressing unit for injecting the molten metal into the cavity;
A vacuum pump for reducing the pressure in the cavity and the inside of the housing; And
And a heat generating unit for heating the first core and the second core.

The method of claim 1,
A temperature controller for interrupting the heating temperature of the heating unit so that the first core and the second core have a predetermined first temperature range and for interrupting the melting temperature of the molten metal so that the molten metal has a predetermined second temperature range Further comprising a molten metal containing a magnesium-based material.

3. The method of claim 2,
Wherein the pressurizing unit further comprises a speed control unit for interrupting a moving speed of the molten metal so that the molten metal has a predetermined injection rate range.

4. The method of claim 3,
Wherein the stationary mold and the movable mold are provided,
Further comprising a cooler for cooling the molten metal injected into the cavity so that the molded product is molded.

4. The method of claim 3,
Between the first core and the second core,
Wherein the sealing member is provided to seal the cavity.

4. The method of claim 3,
Wherein the ejecting portion includes:
A lifting unit movably provided inside the housing;
An ejecting shaft portion provided at the elevating portion to pass through the second core; And
And a lifting and driving part for moving the lifting part.

The method of claim 6,
Between the housing and the elevating portion,
And a sealing member is provided to seal the interior of the housing.

8. The method according to any one of claims 1 to 7,
The cavity
A plurality of main flow paths for branching the molten metal injected through the pressurizing unit;
An auxiliary traveling path which has a thickness equal to or smaller than that of the main traveling path and which communicates with the main traveling path to branch the molten metal traveling through the main traveling path;
A plurality of injection gates having a smaller thickness than the auxiliary transfer path and branching the molten metal in the auxiliary transfer path;
A forming part having a thickness larger than the injection gate and equal to or less than the thickness of the auxiliary transfer path and spaced around the auxiliary transfer path so that the injection gate is mutually communicated; And
And a plurality of vacuum gates branched from the molding part and connected to the vacuum pump,
Wherein the ejecting portion is protrudable from at least one of the injection gate and the vacuum gate.

8. The method according to any one of claims 1 to 7,
The predetermined first temperature range is 200 ° C to 250 ° C,
The predetermined second temperature range is 650 ° C to 700 ° C,
Wherein the predetermined injection rate range is from 2 m / s to 4 m / s.

A mold closing step of moving the first core of the stationary mold and the second core of the movable mold to each other to form a cavity into which the molten metal containing the magnesium-based material is injected;
A core heating step of heating the first core and the second core so as to have a predetermined first temperature range;
A molten metal heating step of heating the molten metal so as to have a predetermined second temperature range;
A vacuum step including a first vacuum step of reducing the pressure of the cavity and a second vacuum step of reducing the pressure of the interior of the housing provided in the stationary mold; And
And a molten metal injection step of injecting the heated molten metal into the depressurized cavity through the vacuum step so as to have a predetermined injection rate range.

11. The method of claim 10,
Further comprising a core cooling step of cooling the first core and the second core to coagulate the molten metal injected into the cavity.

12. The method of claim 11,
A mold separating step of separating the movable mold from the stationary mold so that the first core and the second core are spaced apart when the molten metal solidifies; And
Further comprising a step of separating the molded article from the first core in accordance with solidification of the molten metal.

The method of claim 12,
The thickness of the product, which is produced through the molded product,
A method of die casting using a molten metal containing a magnesium-based material having a thickness of 1.5 mm to 5 mm.

The method according to any one of claims 10 to 13,
The predetermined first temperature range is 200 ° C to 250 ° C,
The predetermined second temperature range is 650 ° C to 700 ° C,
Wherein the predetermined injection rate range is from 2 m / s to 4 m / s.

The method according to any one of claims 10 to 13,
Wherein the vacuum pump maintains the pressure of the cavity at 10 mbar to 50 mbar.