KR20200028606A - Bimetal hollow pipe for hollow channel manufacturing and method of hollow channel manufacturing with gravity casting - Google Patents

Abstract

The present invention relates to a bimetal hollow pipe for blow molding applied to gravity casting, a blow molding mold apparatus using the bimetal hollow pipe, and a blow molding method. Provided is the molding apparatus for manufacturing a hollow molded product, which includes: a first mold in which a first cavity is formed; a second mold in which a second cavity is formed, and which can be closed with the first mold so that the first and second cavities form one cavity; and a pipe which is disposed between the first and second molds so that a hollow is formed inside the molded product formed by injection of melt after closing, and wherein the inside is filled with a predetermined support material. The pipe includes: a first pipe; and a second pipe provided inside the first pipe and having a melting point higher than the melting point of the melt.

Description

Bimetal hollow pipe and blow molding method for blow molding applied to gravity casting {BIMETAL HOLLOW PIPE FOR HOLLOW CHANNEL MANUFACTURING AND METHOD OF HOLLOW CHANNEL MANUFACTURING WITH GRAVITY CASTING}

The present invention relates to a blow molding mold apparatus and a blow molding method using a bimetal hollow pipe and a bimetal hollow pipe for blow molding applied to gravity casting. The present invention relates to a bimetallic hollow tube for blow molding that can be used for forming hollow blows, and a hollow molding mold apparatus and a blow molding method using a bimetallic hollow tube.

In general, in order to manufacture a hollow molded product in which a hollow is formed by GRAVITY CASTING, upper and lower products having hollows are formed, and then the formed upper and lower products are adhered using adhesive means. However, in this case, due to the rigidity problem of the adhesive portion, there is a problem that it is difficult to manufacture a robust product.

To solve this problem, a long tube having a hollow is seated in a mold for manufacturing a product, and after closing the mold, the molten material is melted into the mold to supply a molten metal, that is, a melt, to mold the product. However, even in this case, there is a problem in that the rigidity of the long tube is limited, so that hollow is deformed or destroyed during casting. Therefore, after filling a certain material in the inside of a long tube with a hollow, a technique of removing the product after molding is used.

However, in the past, after forming a hollow product, there is a problem in that it is not easy to remove the material for forming the hollow. In the past, since the hollow forming mechanism used in the tool or device had to be removed after the hollow product was made using a specific tool or device, there was a problem in that the hollow product was complicated and a specific tool or facility was required.

In order to solve the above problems, a hollow product manufacturing method has been disclosed through Korean Patent Publication No. 10-2017-0118309. However, when manufacturing a hollow product, there was a problem that the pipe material melts due to the high temperature of the molten raw material, that is, the melt, and the support material causes indentation on the inner wall of the pipe due to injection pressure.

The present invention is to provide a mold apparatus for manufacturing a hollow molded article and a manufacturing method for preventing a pipe from being damaged by high temperature of a molten stock solution during gravity casting through an embodiment.

The present invention is to provide a mold apparatus for manufacturing a hollow molded article and a manufacturing method for preventing a support material filled in a pipe by an injection pressure of a molten stock solution from generating indentations in a pipe inner wall through an embodiment.

The present invention is to provide a mold apparatus and a manufacturing method for manufacturing a hollow molded article having a high bonding strength between a cooled molten material and a pipe by cooling after being cooled after a part of the outer layer of the pipe is melted by a high temperature of the molten stock solution through an embodiment.

The present invention to solve the above problems, the first mold is formed with a first cavity; A second cavity is formed, and the first mold and the second mold capable of closing the mold so that the first and second cavities form one cavity; And a pipe which is disposed between the first and second molds so that a hollow is formed inside a molded article formed by injection of the melt after the mold closing, and the inside is filled with a predetermined supporting material. ; And a second pipe provided inside the first pipe and having a melting point higher than a melting point of the melt.

The second pipe may have a higher melting point than the melting point of the first pipe.

The first pipe may have a melting point equal to the temperature of the melt so as to be meltable by the melt.

The second pipe may be filled with a predetermined support material inside to prevent deformation of the first pipe due to the pressure of the melt.

The second pipe may have a hardness equal to or greater than the hardness of the support material so that indentation caused by the support material is prevented.

The support material may be a water-soluble material.

The support material may be salt.

The support material may have a higher melting point than the melting point of each of the melt and the second pipe.

The support material may be one of ceramic, sand and metal balls.

Both ends of the pipe is provided on the outside of the cavity, the pipe is provided in the cavity parallel portion disposed parallel to each other; And a curved portion provided inside the cavity to communicate the parallel portions with each other.

The melt and the first pipe may be made of aluminum (Al), and the second pipe may be made of copper (Cu).

The pipe may be formed therein with a single path communicating both ends.

In addition, the present invention is a filling step in which a predetermined support material is filled in the pipe to prevent the pipe from being deformed by the pressure of the melt injected into the cavity of the mold that can be closed; A pipe seating step in which the filled pipe is seated in the cavity; A melt injection step in which the melt is injected into the cavity to surround the pipe; And a cooling and taking out step of cooling the injected melt and taking out the molded article, wherein the injection step is described above by providing a method for manufacturing a blow molded article characterized in that some outer layers of the pipe are melted by the melt. Solve the task.

The pipe may include a first pipe meltable by the melt; And a second pipe provided inside the first pipe and having a melting point higher than a melting point of the melt.

The pipe may include a first pipe meltable by the melt; And a second pipe having a hardness higher than that of the support material.

It may be performed after the cooling and taking out step, and removing step of removing the supporting material from the pipe;

The melt and the first pipe may be made of aluminum (Al), and the second pipe may be made of copper (Cu).

In addition, the present invention provides a hollow product manufacturing method in one aspect. The method for manufacturing a hollow molded article includes filling a support material inside the pipe so that the pipe can withstand the high temperature and high pressure of the molten metal during product molding; Introducing a pipe filled with the support material into a cavity inside a mold for forming the shape of the product; Forming a mold product surrounding the outer circumferential surface of the pipe by introducing molten metal into the cavity inside the mold; And removing the first support material from the inside of the pipe after the molding of the product is completed.

The support material consists of a water-soluble material that is soluble in water, after molding the product

It is configured to inject water into the inside of the pipe to melt the support material inside the pipe by the water to empty the pipe, and the pipe from which the support material is emptied is buried inside to form a hollow product therein. You can. For example, the support material is composed of salt, and when water is introduced into the pipe, the support material may be melted and removed by the water.

Another support material can be completely removed by filling the sand with gravity, removing the inlet and outlet caps, and then removing the pneumatically charged sand, followed by washing with water.

On the other hand, the support material is composed of a particulate material having a strength that the pipe can withstand at the pressure of the molten metal, and the hollow is formed inside the product by the pipe so that the support material is removed from the pipe It may be.

The method for manufacturing a blow molded article is coupled to caps at both ends of the pipe, keeping the support material filled in the pipe filled, and removing the cap during product molding to support the inside of the pipe It can be configured to remove material.

The pipe is formed of a double structure pipe (bimetal pipe) that is physically joined as shown in the figure, so that the pipe is made of aluminum of the same material as the molten metal on the outside, and the pipe can be molded integrally with the hollow molded product and the copper pipe inside. There is a structure that can withstand the high temperature and high pressure of the molten metal during gravity casting.

The pipe may be formed into a continuous continuous loop-type tube so that one end of the pipe is an inlet and the other end is an outlet, and the hollow inside the product can be formed as a single continuous path. The hollow inside the product generated by the pipe may include a plurality of parallel hollow portions parallel to each other and a plurality of connecting hollow portions connecting the parallel hollow portions parallel to each other.

On the other hand, the present invention provides a hollow molded article to which a dual structure pipe (bimetallic pipe) is physically bonded without melting damage and inner wall indentations even at high temperature and high pressure of the aluminum molten stock during aluminum gravity casting. This is a hollow molded article in which a hollow is formed inside, a filling material is filled in the pipe so that the pipe for forming the hollow can withstand the molten metal pressure during product molding, and the mold is formed to form the shape of the product. A pipe filled with the support material is introduced into a cavity of the mold, and molten metal is injected into the cavity inside the mold to form a molded product surrounding the outer circumferential surface of the pipe, and after the molding of the product is completed, the support material is placed inside the pipe. It can be prepared by a process to remove from.

As described above, the mold apparatus for manufacturing a hollow molded article according to the embodiment of the present invention and its manufacturing method have the following effects.

First, according to an embodiment of the present invention, it provides an effect of preventing the pipe from being damaged by the high temperature of the molten stock during gravity casting.

Second, according to an embodiment of the present invention, the support material filled in the pipe by the injection pressure of the molten stock solution provides an effect of preventing indentation on the inner wall of the pipe.

Third, according to an embodiment of the present invention, some of the outer layer of the pipe is melted and then cooled by the high temperature of the molten stock solution, thereby providing a high coupling force between the cooled molten material and the pipe.

1 is an exploded perspective view of a mold apparatus for manufacturing a hollow molded article according to an embodiment of the present invention.
2 is a side cross-sectional view showing a mold apparatus for manufacturing a hollow molded article shown in FIG. 1.
3 is a molded article provided with a hollow manufactured by a mold apparatus for manufacturing a hollow molded article shown in FIG. 1.
4 is a cross-sectional view of the molded article having a hollow shown in FIG. 3, and shows a state in which the support material is filled in the hollow.
5 is a cross-sectional view of a molded article having a hollow shown in FIG. 3, showing a state in which the supporting material is removed from the hollow.

It will be appreciated that the embodiments described below are illustratively shown to help understanding of the invention, and that the present invention can be implemented in various ways different from the embodiments described herein. However, in the description of the present invention, when it is determined that detailed descriptions of related known functions or components may unnecessarily obscure the subject matter of the present invention, detailed descriptions and specific illustrations will be omitted. In addition, the accompanying drawings may not be drawn to scale in order to aid the understanding of the invention, but the dimensions of some components may be exaggerated.

The first and second terms used in the present application may be used to describe various components, but the components should not be limited by the terms. The terms are used only to distinguish one component from other components.

In addition, the terms used in the present application are only used to describe specific embodiments, and are not intended to limit the scope of rights. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise," "consist of," or "consist of" are intended to indicate that a feature, number, step, operation, component, part, or combination thereof described in the specification exists, or It should be understood that it does not preclude the existence or addition possibility of other features or numbers, steps, actions, components, parts or combinations thereof.

Hereinafter, a mold apparatus for manufacturing a hollow molded article and a method of manufacturing the same will be described with reference to FIGS. 1 and 2. 1 is an exploded perspective view of a mold apparatus for manufacturing a hollow molded article according to an embodiment of the present invention, and FIG. 2 is a side sectional view showing a mold apparatus for manufacturing a hollow molded article shown in FIG. 1.

The hollow molded article described below includes a molded article in which a hollow is formed by the use of a mold apparatus using a bimetallic double structure pipe. In addition, a bimetal (bimetal) double structure pipe may be used in the mold apparatus for manufacturing a hollow molded article, and the method for manufacturing a hollow molded article is a method of manufacturing a molded article having a hollow formed therein using the above mold apparatus.

A mold apparatus according to an embodiment of the present invention is a device for manufacturing a molded article having a hollow formed therein. The hollow molded product, which is a molded product having a hollow formed therein, is produced by opening a mold of a mold apparatus and inserting a hollow pipe into a cavity formed inside the mold, followed by mold mold closing and melt injection. The hollow formed inside the molding is formed as the melt injected into the cavity is cooled without being injected into the inner hollow of the pipe 30.

The mold apparatus includes a mold 4 including a first mold 41 and a second mold 42 and a pipe 30 provided between the first mold 41 and the second mold 42.

The first mold 41 has a first cavity 44 formed therein, and a first through hole 45A is provided to allow the pipe 30 to be fitted to one side. The first through groove 45A communicates the outside with the first cavity 44.

The second mold 42 has a second cavity 43 formed therein, and the second cavity 43 has a first cavity 44 when the second mold 42 and the first mold 41 are closed. Together they form a cavity. The second mold 42 is provided with a second through groove 45B so that the pipe 30 can be fitted to one side. The second through groove 45B communicates the outside with the second cavity 43. In addition, the second through groove 45B forms one through groove 45 in which the pipe 30 is located together with the first through groove 45A.

The pipe 30 has both ends provided on the outside of the cavity, and a hole for communicating the hollow and the outside of the pipe 30 is formed in each. A hole provided at one end of both ends may serve as an inlet through which fluid or support introduction described below is introduced, and a hole provided at the other end may serve as an outlet through which fluid or support introduction is discharged. The hole can be opened and closed by the cap 32.

Also, the pipe 30 includes a parallel portion 30A and a curved portion 30B interconnecting the parallel portion 30A, which are provided in the cavity and disposed parallel to each other as shown in FIGS. 1, 4, and 5. do. The parallel portion 30A and the curved portion 30B form one single path, and communicate with the outside through holes formed at each of both ends. Accordingly, the pipe 30 forms a continuous path to be continuously zigzag. However, the pipe 30 is not limited to a zigzag shape, and may be formed in various shapes such as a straight shape.

The pipe 30 is a bimetal (bimetal) double structure, the first pipe 10 forming the outer layer of the double structure and the second pipe located inside the first pipe 10 forming the inner layer of the double structure ( 20). The inner peripheral surface of the first pipe 10 and the outer peripheral surface of the second pipe 20 are joined to each other.

The first pipe 10 may be made of, for example, aluminum (Al) material. The molten raw material injected into the cavity, that is, the molten material used for the melt may be made of the same material as the first pipe 10 material, for example, aluminum. Therefore, when injecting a hot melt, the first pipe 10 may be partially or completely melted. In this case, the thickness of the first pipe 10 may be set in advance so that the entire first pipe 10 is not melted and only the outer portion is melted by injection of the melt.

The second pipe 20 has the same hardness as the support material 50 or higher than the hardness of the support material 50 so that indentation by the support material 50 described later is prevented. Indentation is generally caused when a high temperature melt is injected into a cavity, the pipe has ductility due to high temperature, and at the same time, an injection pressure by the melt is applied, and the inner surface of the pipe presses the support material inside the pipe.

The second pipe 20 may be made of a material having a higher melting point and hardness than the hardness and melting point of each of the molten material of the material and the melt of the first pipe 10. In this case, the first pipe 10 is made of a material having the same or lower hardness than the hardness of the support material 50. Many of the materials with high hardness and melting point have a high price, and many of the materials with low hardness and melting point have a low price. If the first pipe 10 is composed of the same material as the molten material, but composed of a material having a relatively low melting point and hardness, and a relatively inexpensive material, and the second pipe 20 is composed of a material having a relatively high melting point and hardness, As the manufacturing cost is lowered, the pipe 30 of desired performance can be obtained.

The second pipe 20 may be made of, for example, copper (Cu) material. Copper has a higher melting point than aluminum, so it is not damaged even when a molten material is aluminum. When the second pipe 20 is made of a copper material, the hardness of the second pipe 20 is higher than that of the support material 50. Therefore, indentation on the inner circumferential surface of the second pipe 20 due to external pressure is prevented while the inner circumferential surface of the second pipe 20 is in close contact with the support material 50.

Here, the external pressure refers to an injection pressure applied to the outside of the pipe 30 when the melt is injected. When a melt injection pressure is applied to the outer circumferential surface of the first pipe 10, the first pipe 10 and the second pipe 20 are finely compressed, and the inner circumferential surface of the second pipe 20 presses the supporting material 50 do. As described above, since the hardness of the second pipe 20 is higher than that of the support material 50, indentation does not occur on the inner peripheral surface of the second pipe 20.

Furthermore, since the second pipe 20 does not directly contact the melt, the degree of ductility by the high-temperature melt is low, which is advantageous in preventing indentation. This is because the second pipe 20 surrounded by the first pipe 10 in direct contact with the hot melt can be heated to a lower temperature than the first pipe 10 to maintain a unique hardness value at a considerable level.

On the other hand, deformation of the pipe 30 may occur due to the pressure of the melt when the melt is injected into the cavity. Therefore, the support material 50 is filled in the pipe 30 to prevent deformation of the pipe 30 by the pressure of the melt.

In this regard, the method for manufacturing a hollow molded article of the present invention comprises filling the support material 50 inside the pipe 30 and blocking the inlet of the pipe 30 filled with the support material 50 with a cap 32 Giving and inserting the pipe 30 into a cavity inside the mold 4 for injecting a melt (for example, an aluminum raw material liquid), and injecting a melt into the cavity of the mold 4, and the pipe It includes the step of removing the support material from the inside of the pipe 30 after the molded article having a hollow formed therein is molded by (30).

The support material 50 may be a water-soluble material. In this case, when water is injected into the pipe 30 after production of the molded article 40 as shown in FIGS. 3 to 5, the support material 50 inside the pipe 30 is melted by water to pipe (30) is emptied and the support material (50) is buried inside the emptied pipe (30) to form a hollow product therein.

The water-soluble material can be composed of salt. Salt can be removed by melting by the water introduced into the interior of the pipe (30). The melting point of salt is higher than that of aluminum. If the pipe 30 is made of aluminum and the molten material is also aluminum, a part of the pipe 30 is melted and integrally formed with the melt, while the shape of the salt can be maintained. Therefore, the pipe 30 can withstand the injection pressure of the melt. The pipe 30 is prevented from being crushed by the injection pressure of the melt. When the pipe 30 is supported by the salt, the melt and the pipe 30 are integrated, and at the same time, a molded article having a hollow inside can be molded by the pipe 30.

When the pipe 30 is supported by the salt, the melt is injected and the molded article 40 is molded, and then the caps 32 attached to both ends of the pipe 30 are removed, and water is supplied to the pipe 30. If the salt is melted by injection, the salt may be removed from the pipe 30.

Hereinafter, in the method of manufacturing a hollow article formed of the present invention 40, after the molding of the article 40 is completed, the following method to effectively remove the soluble material remaining inside the pipe 30 buried in the product use.

After filling the salt in the interior of the pipe 30, the molten metal is injected into the cavity of the mold 4 at a constant pressure while the pipe 30 is put into the cavity of the mold 4 so that the pipe 30 and the melt are The integrated preform 40 is molded. A cavity for molding the molded article 40 is formed inside the mold 4 in a state where the first mold 41 and the second mold 42 are closed.

Filling a salt (salt) inside the pipe (30) and injecting the melt into the cavity of the mold (4) while filling the pipe (30) into the cavity inside the mold (4) for product molding to create the appearance of the product will be. Next, when water of a certain pressure is injected into the pipe in the direction of the arrow shown in FIG. 5 into the interior of the pipe 30, since the water melts the salt, the salt is removed, and when the salt is removed, the pipe 30 is inside It can be buried to form a molded article 40 having a hollow inside by an empty pipe 30.

On the other hand, according to another embodiment of the present invention, the support material 50 may be composed of a particulate material having a strength that the pipe 30 can withstand at the injection pressure of the melt, the interior of the product by the pipe 30 After the hollow is formed in the support material 50 may be removed from the pipe (30). At this time, the particulate material may be composed of a material having a higher melting point than the melting point of the pipe 30 and the high temperature of the melt, such as ceramic, sand, and balls (metal balls, that is, steel balls).

As described above, when the pipe 30 is aluminum and the melt is also a high temperature aluminum melt stock, the melting point of the particulate support material 50 (particulate material) made of ceramic or steel balls is higher than that of aluminum, and thus the pipe 30 While a part of it is melted and formed integrally with the melt, the particulate support material 50 is maintained in its shape so that the pipe 30 can withstand the injection pressure of the melt. The pipe 30 is prevented from being crushed by the injection pressure of the melt. In the state in which the pipe 30 is supported by the support material 50, the melt and the pipe 30 are integrated, and at the same time, the molded product 40 having a hollow inside may be molded by the pipe 30.

After the pipe 30 is supported by the particulate support material 50, the melt is injected and the molded article is molded, then the cap 32 coupled to the inlet of the pipe 30 is taken out, and then the particulate support material 50 ) By blowing air at one end of the pipe 30 in the direction of the arrow shown in FIG. 5 to elute and remove the other end. If necessary, pressure water having a constant pressure is injected into the pipe 30 to remove the particulate support material 50 by the injection pressure of water.

Meanwhile, the cap 32 coupled to the pipe 30 is disposed outside the cavity. The pipe 30 is introduced into a cavity inside the mold 4, and then a melt is injected into the cavity of the mold 4 to mold a molded article. Then, since the cap 32 is exposed to the outside of the molded product, the cap 32 can be removed from the pipe 30. After the cap 32 is removed from the pipe 30, when the salt is filled inside the pipe 30, water is injected to melt the salt to remove it, and the corrugated interior is filled with particulate support materials such as ceramic, sand or steel balls. If present, when the cap 32 is removed and air is blown inside one end of the pipe 30, particulate matter is eluted toward the other end and is removed.

As described above, although the present invention has been described by limited embodiments and drawings, the present invention is not limited by this, and the technical spirit of the present invention and the following will be described by those skilled in the art to which the present invention pertains. Of course, various modifications and variations can be made within the scope of the equivalent claims.

4: mold 10: first pipe
20: second pipe 30: pipe
32: cap (32) 41: first mold
42: second mold 45: through hole

Claims (17)

A first mold in which a first cavity is formed;
A second cavity is formed, and the first mold and the second mold capable of closing the mold so that the first and second cavities form one cavity; And
The pipe is disposed between the first and second molds so that a hollow is formed inside the molded article formed by injection of the melt after the mold closing, and the inside is filled with a predetermined support material.
The pipe
A first pipe; And a second pipe provided inside the first pipe and having a melting point higher than a melting point of the melt. According to claim 1,
The second pipe has a melting point higher than the melting point of the first pipe, characterized in that the mold apparatus for manufacturing a hollow molded article. According to claim 1,
The first pipe has a melting point equal to the temperature of the melt so that it can be melted by the melt. According to claim 1,
The second pipe is molded device for manufacturing a hollow molded article, characterized in that the inside is filled with a predetermined support material to prevent deformation of the first pipe due to the pressure of the melt. According to claim 4,
The second pipe has a mold equal to the hardness of the support material or a hardness higher than the hardness of the support material so as to prevent indentation caused by the support material when the melt is injected. According to claim 4,
The support material is a mold apparatus for manufacturing a hollow molded article, characterized in that it is a water-soluble material. The method of claim 6
The support material is a mold apparatus for manufacturing a hollow molded article, characterized in that the salt. According to claim 4,
The supporting material has a melting point higher than the melting point of each of the melt and the first pipe, characterized in that the molding apparatus for manufacturing a hollow molded article. The method of claim 8
The support material is a mold device for manufacturing a hollow molded article, characterized in that one of ceramic, sand and metal balls. According to claim 1,
Both ends of the pipe are provided on the outside of the cavity,
The pipe is provided in the cavity, the parallel portion disposed parallel to each other; And a curved portion provided in the cavity to communicate the parallel portions with each other. According to claim 1,
The melt and the first pipe are made of aluminum (Al),
The second pipe is a mold apparatus for manufacturing a hollow molded article, characterized in that it is made of copper (Cu). According to claim 1,
The pipe is a mold device for manufacturing a hollow molded article, characterized in that a single path communicating between both ends is formed therein. A filling step in which a predetermined supporting material is filled in the pipe to prevent the pipe from being deformed by the pressure of the molten metal injected into the cavity of the mold that can be molded;
A pipe seating step in which the filled pipe is seated in the cavity;
A melt injection step in which the melt is injected into the cavity to surround the pipe; And
It includes; cooling and taking out steps to cool the injected melt and take out the molded article,
The injection step is a method for manufacturing a hollow molded article, characterized in that some outer layers of the pipe are melted by the melt. The method of claim 13,
The pipe
A first pipe meltable by the melt; And a second pipe provided inside the first pipe and having a melting point higher than a melting point of the melt. The method of claim 13,
The pipe
A first pipe meltable by the melt; And a second pipe having a hardness higher than that of the support material. The method of claim 13,
A method of manufacturing a blow-molded article, which is performed after the cooling and taking-out steps, and further includes removing the support material from the pipe. The method of claim 13,
The melt and the first pipe are made of aluminum (Al),
The second pipe is a mold apparatus for manufacturing a hollow molded article, characterized in that it is made of copper (Cu).

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