KR102491053B1 - Shell For Mold, Method For Manufacturing The Shell For Mold, Mold, Manufacturing Method For The Mold And Method For Manufacturing Casting By using The Mold - Google Patents

Abstract

The present invention provides a shell for a mold, a method for manufacturing a shell for a mold, a mold, a mold manufacturing method, and a casting manufacturing method using a mold that reduce manufacturing time and manufacturing cost by manufacturing a high-quality mold through 3D printing.

Description

Shell For Mold, Method For Manufacturing The Shell For Mold, Mold, Manufacturing Method For The Mold And Method For Manufacturing Casting By using The Mold}

The present invention relates to a shell for a mold, a method for manufacturing a shell for a mold, a mold, a mold manufacturing method, and a casting manufacturing method using a mold, and more particularly, to a shell for a mold using 3D printing technology, a method for manufacturing a shell for a mold, a mold, a mold manufacturing method, and It relates to a casting manufacturing method using a mold.

Mold refers to metal materials and manufacturing technology for mass production of parts and products of the same size and exact shape.

Conventionally, machining was mainly used to manufacture molds, but when manufacturing molds by this cutting process, the size of the mold is In the case of a large or complex shape, not only the processing time and cost required for mold processing are excessively high, but also, when manual work is partially required, the precision and completeness of the mold vary depending on the skill level of the operator.

The method of manufacturing a mold by cutting process has a problem in that it is not possible to manufacture a mold of uniform quality because not only the time and cost required for manufacturing are excessive, but also manual work is required for model processing.

3D printing is an additive manufacturing process technology that freely creates a three-dimensional solid shape by stacking raw materials such as liquid or powder. After creating 3D data for a target object with a 3D design program, It is a technique of repeatedly stacking thin layers in the shape of Recently, 3D printing technology is expected to be a key technology that will bring innovation in manufacturing process technology by replacing or supplementing some of the existing cutting processes.

In particular, mold manufacturing technology using 3D printing is attracting attention as an environmentally friendly method that can reduce waste of materials compared to conventional methods. Furthermore, many studies are being conducted to develop molds having various structures using 3D printing.

Registered Patent No. 10-1784371 Registered Patent Publication

In order to solve the problems of the prior art described above, the present invention is a high-quality mold shell and mold including a cooling channel corresponding to the shape of the casting and a thermal deformation prevention unit of the mold to enable uniform cooling of the casting through 3D printing is intended to provide

In addition, an object of the present invention is to provide a method for manufacturing a shell for a mold and a method for manufacturing a mold that reduces the manufacturing time and manufacturing cost of the mold shell and mold through 3D printing.

In addition, it is an object of the present invention to provide a casting manufacturing method using a mold that reduces production time and manufacturing cost of a casting by using a mold shell and a mold manufactured through 3D printing.

In order to achieve the above object, a shell for a mold according to the present invention includes a contact portion provided to correspond to the shape of a casting and having a contact surface with the material of the casting; a side wall portion formed along an edge of the contact portion and extending downward; a bottom portion provided at a lower end of the side wall portion to form a lower surface; a plurality of support parts extending from the bottom part to the contact part; and a cooling channel formed adjacent to the contact portion to uniformly cool the material of the casting.

In addition, the mold shell further includes a thermal deformation preventing portion located on an inner surface of the contact portion and preventing deformation due to molten metal forming the metal portion.

In addition, the thermal deformation prevention unit includes a plurality of polygonal portions that are repeatedly formed by sharing one corner with each other, and the polygonal portion has a shape protruding from an inner surface of the contact portion.

In addition, the cross section of the cooling channel has a lower half-circle shape and an upper portion of a hat shape.

In addition, the cooling channel includes a plurality of grooves formed in a longitudinal direction on an inner surface of the cooling channel.

In addition, the bottom portion includes at least one through hole through which molten metal can be injected or a riser can be connected.

On the other hand, the mold according to the present invention, in the mold, the shell constituting the frame of the mold; and a metal part positioned in the inner space formed by the shell, wherein the shell is provided to correspond to the shape of the casting and has a contact portion having a contact surface with the material of the casting, and is formed along the edge of the contact portion to the lower part. an extending side wall portion, a bottom portion provided at a lower end of the side wall portion to form a bottom surface, and a plurality of support portions extending from the bottom portion to the contact portion; and a cooling channel formed adjacent to the contact portion to uniformly cool the material of the casting.

In addition, the shell, located on the inner surface of the contact portion, to prevent deformation due to the molten metal forming the metal portion; further includes.

On the other hand, in the method for manufacturing a shell for a mold according to the present invention, in the method for manufacturing a shell for a mold constituting a frame of a mold, preparing 3D printing data containing structural information of the shell; preparing metal powder used as a material for the shell; and melting and hardening the metal powder, wherein the shell is provided to correspond to the shape of the casting and has a contact portion having a contact surface with the material of the casting, and a side wall portion formed along an edge of the contact portion and extending downward. , A bottom portion provided at the lower end of the side wall portion to form a bottom, a plurality of support portions extending from the bottom portion to the contact portion, and a cooling channel formed adjacent to the contact portion to uniformly cool the material of the casting. and, according to the 3D printing data, a process of preparing the metal powder and a process of melting and curing the metal powder are repeatedly performed.

In addition, the shell, located on the inner surface of the contact portion, to prevent deformation due to the molten metal forming the metal portion; further includes.

In addition, the cross section of the cooling channel has a lower half-circle shape and an upper portion of a hat shape.

On the other hand, in the mold manufacturing method according to the present invention, in the mold manufacturing method having a mold shell according to claim 1, the step of preparing the shell; injecting molten metal into the inner space formed by the shell; and cooling the molten metal injected into the inner space.

On the other hand, the method of manufacturing a casting using a mold according to the present invention, the step of preparing a first mold having a contact portion corresponding to the shape of one side of the casting; Preparing a second mold having a contact portion corresponding to the shape of the other side of the casting; forming a cavity by bringing the first mold and the second mold into contact with each other; injecting the casting material into the cavity; cooling the material of the casting; And separating the casting obtained in the cooling process from the first mold and the second mold; including, but the first mold and the second mold are molds according to any one of claims 7 or 8 characterized by

In addition, in the cooling process, the temperature of the material of the casting is lowered by passing cooling water through the cooling channel.

The present invention can reduce the manufacturing cost, manufacturing time, etc. of a mold by manufacturing a shell for a mold through 3D printing.

In the present invention, by manufacturing a shell for a mold through 3D printing, the contact portion can be easily deformed only by designing simple 3D data.

The present invention can minimize thermal deformation of the shell when the molten metal is filled in the inner space of the shell by forming a plurality of support portions extending from the bottom portion to the contact portion.

According to the present invention, a shape-adaptive cooling channel may be formed, and the cooling channel may be provided along the inner surface of the contact portion that changes according to the shape of the casting.

According to the present invention, thermal deformation of the shell can be minimized when the molten metal is filled in the inner space of the shell by providing the thermal deformation preventing portion on the inner surface of the contact portion.

The thermal deformation preventing unit of the present invention includes a plurality of polygonal portions to more firmly support the contact portion, thereby minimizing thermal deformation of the shell when filling the inner space of the shell with molten metal.

In the present invention, by adopting the shape of a water droplet with a lower half circle shape at the cross section of the cooling channel and a hatchet shape at the upper part of the cross section of the cooling channel, a space for a solid and large amount of cooling water to flow without collapsing the shape even though it is a layered method by 3D printing. This wide cooling channel can be formed.

The present invention can save casting time and manufacturing cost by manufacturing a casting using a first mold and a second mold manufactured through 3D printing.

1 shows a cross section of a mold according to an embodiment of the present invention.
2 shows a thermal deformation prevention unit according to an embodiment of the present invention.
3 shows the overall shape of a shell for a mold according to an embodiment of the present invention.
Figure 4 compares the case where the cross section is formed in the shape of a circle and a water droplet when manufacturing a cooling channel.
5 shows a longitudinal section of a cooling channel according to an embodiment of the present invention.
6 shows a sequence of a method for manufacturing a shell for a mold according to an embodiment of the present invention.
7 shows a shell manufacturing method according to an embodiment of the present invention.
8 shows a sequence of a mold manufacturing method according to an embodiment of the present invention.
9 shows a mold manufacturing method according to an embodiment of the present invention.
10 shows a sequence of a casting manufacturing method using a mold according to an embodiment of the present invention.
11 shows a state in which a cavity is formed according to an embodiment of the present invention.
12 shows a state in which a casting is separated from a mold according to an embodiment of the present invention.

Specific structural or functional descriptions of the embodiments according to the concept of the present invention disclosed in this specification are only illustrated for the purpose of explaining the embodiments according to the concept of the present invention, and the embodiments according to the concept of the present invention It can be embodied in various forms and is not limited to the embodiments described herein.

Embodiments according to the concept of the present invention can apply various changes and have various forms, so the embodiments are illustrated in the drawings and described in detail in this specification. However, this is not intended to limit the embodiments according to the concept of the present invention to specific disclosure forms, and includes all changes, equivalents, or substitutes included in the spirit and technical scope of the present invention.

All terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the technology disclosed in this specification belongs, unless otherwise specifically defined herein. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and unless explicitly defined in this specification, it should not be interpreted in an ideal or excessively formal meaning. Should not be.

Hereinafter, a mold shell, a mold, a mold shell manufacturing method, a mold manufacturing method, and a casting manufacturing method using a mold according to an embodiment of the present invention will be described.

First, a look at the most basic shell for a mold according to an embodiment of the present invention.

1 shows a cross section of a mold according to an embodiment of the present invention.

Referring to Figure 1, the mold shell according to an embodiment of the present invention is provided to correspond to the shape of the casting 40, the contact portion 100 having a contact surface with the material of the casting 40; a sidewall portion 200 formed along an edge of the contact portion 100 and extending downward; a bottom portion 300 provided at a lower end of the side wall portion 200 to form a lower surface; a plurality of support parts 400 extending from the bottom part 300 to the contact part 100; and a cooling channel 500 formed adjacent to the contact portion 100 to uniformly cool the material of the casting 40 .

A shell for a mold according to an embodiment of the present invention may include a contact portion 100 . The contact portion 100 may be provided to correspond to the shape of the casting 40 . In addition, it may have a contact surface with the material of the casting 40.

The contact part 100 may be provided in various shapes according to the casting 40 . The shape of the contact portion 100 may be determined by 3D printing data. The contact portion 100 may be formed to be curved in various shapes, thereby determining the shape of the casting 40 to be produced.

Finally, the mold according to the present invention can manufacture the casting 40 through two or more molds. The first mold 10 corresponding to one side of the casting 40 may be manufactured, and the second mold 20 corresponding to the other side of the casting 40 may be manufactured. The contact portion 100 of the first mold 10 and the second mold 20 may be provided to correspond to the shape of the casting 40 .

The contact portion 100 may form a cavity 30 . The cavity 30 is a part in which the shape of the casting 40 is formed, and means a part in the form of a sedimentation. Also, the contact portion 100 may form a core. The contact portion 100 may form a cavity 30 or a core according to a shape.

A shell for a mold according to an embodiment of the present invention may include a side wall portion 200 . The side wall portion 200 may be formed along an edge of the contact portion 100 and extend downward. The side wall portion 200 may form a side frame of a shell and a mold to be finally manufactured by forming a side surface.

A shell for a mold according to an embodiment of the present invention may include a bottom portion 300 . The bottom part 300 may be provided at a lower end of the side wall part 200 to form a lower surface. The bottom part 300 may be positioned to face the contact part 100 . The bottom portion 300 may form a bottom surface to form a shell for a mold finally manufactured and a bottom surface skeleton of a mold.

The contact portion 100, the side wall portion 200, and the bottom portion 300 form the exterior of the mold shell, and the molten metal 70 may be injected into the formed mold shell.

A shell for a mold according to an embodiment of the present invention may include a support part 400 . The support part 400 may be formed to extend from the bottom part 300 to the contact part 100 . The support part 400 may be provided in plurality.

Referring to FIG. 1 , the bottom portion 300 may be positioned below the shell for a mold and the contact portion 100 may be positioned at the top. The support part 400 is formed to extend from the bottom part 300 to the contact part 100, and can support the mold shell from the inside. Specifically, some of the plurality of support parts 400 may directly support the contact surface. Also, some of the plurality of support parts 400 may support the cooling channel. In addition, some of the plurality of support parts 400 may start from the cooling channel to support the contact surface.

The support part 400 may have a thin pillar shape. A plurality of support parts 400 may be provided to form a skeleton of a shell for a mold. Therefore, the molten metal 70 can be injected into the shell for a mold having an internal skeleton formed thereon.

In addition, the support 400 may minimize thermal deformation of the mold shell when the molten metal 70 is injected into the mold shell. Materials expand when heated and contract when cooled. At this time, if the temperature of the material is not uniform, deformation may occur.

Since the molten metal 70 has a high temperature, heat can be transferred to the mold shell. When the molten metal 70 is injected into the shell for the mold, the shell for the mold is heated and a temperature difference may occur in each part and deformation due to heat may occur. In particular, the contact part 100 is related to the shape of the casting 40 and is the most sensitive part to thermal deformation. In this case, the support portion 400 is formed from the bottom portion 300 and extends to the contact portion 100, thereby minimizing thermal deformation caused by the molten metal 70.

A shell for a mold according to an embodiment of the present invention may include a cooling channel 500 . The cooling channel 500 may be formed adjacent to the contact portion 100 . The cooling channel 500 may cool the material of the casting 40 .

In casting technology through a mold, the cooling channel 500 has the greatest influence on the dimensional precision and deformation of the casting 40 and consumes the greatest amount of time in the casting process. According to an embodiment of the present invention, the shell for a mold is made by an additive manufacturing process in which a product is manufactured by stacking one layer at a time, unlike the conventional cutting process method, and may be provided with a conformal cooling channel 500.

When the cooling channel 500 is provided in a shape-adaptive type, the complexity of the cooling channel 500 may be increased and designed to closely adhere to the outer shape of the casting 40 . This is possible by following the additive manufacturing method through 3D printing, which can speed up the production of castings.

The cooling channel 500 is designed to be in close contact with the outer shape of the casting 40, that is, the contact part 100, and can uniformly cool the entire contact part 100. As a result, the outer appearance of the casting 40 can be uniformly cooled, and each part of the casting 40 can be maintained at a uniform temperature, thereby reducing the cooling time and greatly affecting product quality improvement.

Since the existing cooling channel 500 increases complexity and is difficult to form along the contact portion 100, the casting 40 cannot maintain a uniform temperature in each part. As a result, each part of the casting has a different cooling time, which increases the overall cooling time and causes thermal deformation, which may adversely affect product quality.

Such a structure can be obtained when manufacturing a shell for a mold by 3D printing. The shape of the contact portion 100 corresponding to the shape of the casting 40 may be introduced into the 3D printing data, and the position and shape of the cooling channel 500 may be adjusted so as to be adjacent to the contact portion 100 along the shape of the contact portion 100. can be introduced

A shell for a mold according to an embodiment of the present invention may be manufactured through 3D printing. The contact portion 100 can be easily formed to correspond to the shape of the casting 40 only by designing 3D printing data. In addition, the cooling channel 500 may be formed adjacent to the contact portion 100 along the contact portion 100 . As a result, manufacturing time and manufacturing cost can be reduced.

Next, look at the thermal deformation prevention part 600 included in the mold shell.

2 shows a thermal deformation prevention unit 600 according to an embodiment of the present invention.

Referring to FIG. 2 , the mold shell according to the embodiment of the present invention is located on the inner surface of the contact part 100 and prevents deformation by the molten metal 70 forming the metal part 700. A prevention unit 600 may be further included.

The mold shell may include a thermal deformation prevention unit 600 . The thermal deformation prevention part 600 may be located on the inner surface of the contact part 100 . The thermal deformation prevention unit 600 may prevent deformation due to the molten metal 70 .

The contact part 100 may be provided to correspond to the shape of the casting 40, and the thermal deformation prevention part 600 may be provided according to the shape of the contact part 100 corresponding to the shape of the casting 40. The thermal deformation prevention part 600 may be formed along the curve of the contact part 100 .

The thermal deformation prevention unit 600 may minimize thermal deformation of the mold shell by the molten metal 70 . Since the molten metal 70 has a high temperature, it may cause thermal deformation of the mold shell and thermal deformation of the contact portion 100 in the mold shell.

The contact portion 100 is related to the shape of the casting 40 and corresponds to a configuration most sensitive to thermal deformation. In particular, the thermal deformation prevention unit 600 can minimize thermal deformation of the contact unit 100 . The thermal deformation prevention part 600 is not provided in a plate shape, but is formed in a form protruding from the contact part 100 . A detailed structure for this will be described below.

Next, look at the specific shape of the thermal deformation prevention unit 600.

With continued reference to FIG. 2, according to an embodiment of the present invention, the thermal deformation prevention unit 600,

It includes a plurality of polygonal parts 610 that are repeatedly formed by sharing one corner with each other, and the polygonal parts 610 may be formed in a shape protruding from the inner surface of the contact part 100 .

The thermal deformation prevention part 600 may include a plurality of polygonal parts 610 . The plurality of polygonal portions 610 may be repeatedly formed by sharing one corner with each other. The polygonal portion 610 may be formed in a shape protruding from the inner surface of the contact portion 100 .

Each polygonal portion 610 may have a polygonal column shape with an open bottom. Referring to FIG. 1 , the upper end of the polygonal part 610 may be closed by being connected to the contact part 100, the lower end of the polygonal part 610 may be opened, and the side surface of the polygonal part 610 may be the contacting part. It may be formed protruding from (100).

When viewing the inner surface of the contact portion 100 from the front according to FIG. 2 , the polygonal portion 610 may have a hexagonal shape. This is just one embodiment, and the polygonal portion 610 may be formed of a polygon such as a quadrangle or a triangle.

The plurality of polygonal parts 610 may share one edge with each other. The thermal deformation prevention unit 600 may minimize thermal deformation of the contact portion 100 caused by the molten metal 70 . At this time, since the thermal deformation prevention part 600 includes a plurality of polygonal parts 610 sharing one corner, the plurality of polygonal parts 610 can be more stably and firmly coupled to the contact part 100, and mutually It can be connected to minimize thermal deformation.

On the other hand, the polygonal portion 610 is not necessarily made of a polygon, but may be made of a circle. At this time, the plurality of polygonal parts 610 may be formed by sharing a point on the circumference of each other.

In addition, the polygonal portion 610 may have various shapes, but in particular, the hexagonal structure (honeycomb structure) of the polygonal portion 610 can be maintained as a stable structure despite changes in the external physical environment (force, heat). . The polygonal portion 610 can support the contact portion 100 more firmly while reducing consumption of the metal powder 90 , and can minimize thermal deformation of the contact portion 100 .

As described above, since the polygonal portion 610 has a structure that minimizes the volume, thermal deformation of the polygonal portion 610 itself can be minimized and the contact portion can be more firmly supported.

Next, the relationship between the cooling channel 500 and the support 400 will be examined.

3 shows the overall shape of a shell for a mold according to an embodiment of the present invention. FIG. 4 compares the case where the cooling channel 500 is manufactured in a circular cross section and a water drop shape.

Referring to FIGS. 1 and 3 , the cooling channel 500 according to the embodiment of the present invention may be located inside the mold shell. The cooling channel 500 may be formed in a tubular shape so as to be adjacent to the contact portion 100 . At this time, the plurality of support parts 400 may lift and support the cooling channel 500 . The cooling channel 500 may be formed on one or more support parts 400 .

Next, a cross section of the cooling channel 500 formed on the support part 400 will be described.

Referring to FIG. 4 , according to an embodiment of the present invention, the cross section of the cooling channel 500 may have a lower half-circle shape and an upper portion of a hat shape.

A cross section of the cooling channel 500 may have a lower half circular shape. Also, an upper portion of the cooling channel 500 may have a hat shape. Hereinafter, for convenience, it is referred to as a 'waterdrop shape'.

The cooling channel 500 may be formed in a layered manner by 3D printing. Since the bottom of the cooling channel 500 has a lower semicircular shape based on the cross section, there is no difficulty in the stacking process. On the other hand, when the upper portion is formed in a semicircular shape, that is, when the entire cross section of the cooling channel 500 is formed in a circular shape, the following problems may occur.

For ease of explanation, materials continuously stacked by 3D printing are arbitrarily subdivided and described. The already laminated material is referred to as the first material, and the newly laminated material is referred to as the second material. The cooling channel 500 may be manufactured by laminating the second material on the first material by 3D printing. In order to stack the second material, the first material supporting the second material must be firmly maintained, and the center of gravity of the second material must be located on the first material.

When forming the cross section of the cooling channel 500 in a circular shape larger than a certain diameter, in the process of stacking the top of the cooling channel 500 when forming the cooling channel 500 in which the metal powder 90 is melted and stacked, The second material may not be stacked on top of the first material and may collapse. On the other hand, when the cross section of the cooling channel 500 is formed in a droplet shape, the second material is easily stacked on top of the first material in the process of stacking the top of the cooling channel 500 .

Specifically, in the case of FIG. 4(a), since the center of gravity of the second material is not located on the first material during the stacking process of the second material, the second material may flow down toward the inside of the cooling channel 500. That is, when the cross section of the cooling channel 500 is formed in a circular shape larger than a predetermined diameter, the second material may collapse toward the inside of the cooling channel 500 .

On the other hand, in the case of FIG. 4(b), since the center of gravity of the second material is located on the first material in the process of stacking the second material, the second material can be stacked on the first material. Therefore, when the cross section of the cooling channel 500 is formed in a droplet shape, the shape of the cooling channel 500 can be stably maintained regardless of the size of the cross section of the droplet shape.

For the above reasons, when the cross section of the cooling channel 500 is formed in a water drop shape, the cooling channel 500 can be formed more robustly and stably when manufacturing the cooling channel 500 using 3D printing.

In addition, when the cross section of the cooling channel 500 is in the form of a water droplet, the material does not collapse when the cooling channel 500 is made large. On the other hand, when the cross section of the cooling channel 500 is circular, the material collapses when the diameter of the circle is large.

Nevertheless, the shape of the cross section of the cooling channel 500 is not limited to the water drop shape. The cross section of the cooling channel 500 may be formed in various shapes such as circular and polygonal shapes.

Next, the shape of the inner surface of the cooling channel 500 will be examined.

5 shows a longitudinal cross-section of a cooling channel 500 according to an embodiment of the present invention.

Referring to FIG. 5 , according to an embodiment of the present invention, the cooling channel 500 may include a plurality of grooves formed in the longitudinal direction on an inner surface of the cooling channel 500 .

The cooling channel 500 includes a plurality of grooves formed in the longitudinal direction on the inner surface of the cooling channel 500, so that the cooling channel 500 can increase its cross-sectional area with the cooling water. Therefore, the cooling channel 500 can provide a greater cooling effect when manufacturing a casting. In addition, the plurality of grooves of the cooling channel 500 may provide a path through which cooling water flows smoothly.

Since the cooling channel 500 including a plurality of grooves can bring more heat from the casting 40, manufacturing time and manufacturing cost can be reduced.

Next, look at the bottom portion 300 including the through hole 310.

Referring back to FIG. 3 , according to an embodiment of the present invention, the bottom portion 300 may include at least one through hole 310 through which molten metal 70 may be injected or a riser may be connected. .

The bottom portion 300 may include one or more through holes 310 . The through hole 310 may inject the molten metal 70 and may connect a riser.

A through hole 310 may be formed in the bottom portion 300 of the mold shell according to an embodiment of the present invention to inject molten metal 70 therein, and the molten metal 70 may be cooled to finally manufacture a mold. can do.

When the molten metal 70 is injected into the inside of the mold shell, the riser may release air inside the mold shell to the outside. In addition, the riser may overflow a portion of the molten metal 70 to prevent shrinkage defects occurring as the molten metal 70 cools. The through hole 310 may connect the riser and may serve as an injection part of the molten metal 70 .

When two or more through holes 310 are formed in the bottom part 300 , the molten metal 70 may be injected through one through hole 310 and the riser may be connected to the other through hole 310 .

Next, look at the mold.

Referring back to Figure 1, the mold according to the embodiment of the present invention, in the mold,

a shell constituting a frame of the mold; And a metal part 700 positioned in the inner space formed by the shell; the shell is provided to correspond to the shape of the casting 40 and has a contact surface with the material of the casting 40 (100). ), the sidewall portion 200 formed along the edge of the contact portion 100 and extending downward, the bottom portion 300 provided at the lower end of the sidewall portion 200 to form a bottom, and the bottom portion 300 a plurality of support parts 400 extending from the contact part 100; and a cooling channel 500 formed adjacent to the contact portion 100 to uniformly cool the material of the casting 40 .

A mold according to an embodiment of the present invention may include a shell. As described above, the shell means a shell for a mold. The shell may include a metal part 700, a contact part 100, a side wall part 200, a bottom part 300, a plurality of support parts 400, and a cooling channel 500. Structures and effects of the metal part 700, the contact part 100, the side wall part 200, the bottom part 300, the plurality of support parts 400, and the cooling channel 500 are the same as those described above, so they will be omitted.

A mold according to an embodiment of the present invention may include a metal part 700 . In a mold, the shell can act as a skeleton. A mold can be manufactured by positioning the metal part 700 in the inner space of the shell.

In the case of manufacturing all parts of the mold through 3D printing, a cost problem of the metal powder 90 as a printing material may occur. In order to reduce manufacturing time and manufacturing cost according to the purpose of the present invention, a shell, which is a skeletal structure, is manufactured by 3D printing, and molten metal 70 is injected into the inner space of the shell and cooled to manufacture a final mold. .

The metal part 700 may be formed by injecting molten metal 70 into the finished shell. The metal part 700 may be formed inside the shell by injecting the molten metal 70 through the through hole 310 of the bottom part 300 and then cooling the molten metal 70 .

In addition, according to an embodiment of the present invention, the shell is located on the inner surface of the contact portion 100, and prevents deformation by the molten metal 70 forming the metal portion 700. (600); may further include.

The mold may include a shell, and the shell may include the thermal deformation prevention unit 600 . Since the shell is the same as the aforementioned mold shell, and the thermal deformation prevention unit 600 has also been described above, it will be omitted.

According to an embodiment of the present invention, the mold is provided to correspond to the shape of the casting 40, the contact portion 100 having a contact surface with the material of the casting 40; a sidewall portion 200 formed along an edge of the contact portion 100 and extending downward; a bottom portion 300 provided at a lower end of the side wall portion 200 to form a lower surface; a plurality of support parts 400 extending from the bottom part 300 to the contact part 100; and a cooling channel 500 formed adjacent to the contact portion 100 to uniformly cool the material of the casting 40 .

In addition, the mold may include a thermal deformation prevention unit 600, and the thermal deformation prevention unit 600 includes a plurality of polygonal portions 610 that are repeatedly formed by sharing one corner with each other. Each part 610 may have a shape protruding from the inner surface of the contact part 100 .

In addition, the cross section of the cooling channel 500 may have a lower half circular shape and an upper upper hat shape.

In addition, the cooling channel 500 may include a plurality of grooves formed in the longitudinal direction on an inner surface of the cooling channel 500 .

In addition, the bottom portion 300 may include at least one through hole 310 through which molten metal 70 may be injected or a riser may be connected.

Next, a method for manufacturing a shell for a mold will be described.

6 shows a sequence of a method for manufacturing a shell for a mold according to an embodiment of the present invention.

Referring to FIG. 6, in the method for manufacturing a shell for a mold according to an embodiment of the present invention, in the method for manufacturing a shell for a mold constituting a frame of a mold, preparing 3D printing data containing structural information of the shell (S100); Preparing metal powder used as a material for the shell (S200); And a step of melting and curing the metal powder (S300), wherein the shell is provided to correspond to the shape of the casting 40 and has a contact surface with the material of the casting 40, the contact portion 100, the contact portion The side wall portion 200 formed along the edge of the 100 and extending downward, the bottom portion 300 provided at the lower end of the side wall portion 200 to form a bottom surface, and the contact portion from the bottom portion 300 ( 100) and a cooling channel 500 formed adjacent to the contact portion 100 to uniformly cool the material of the casting 40, and the 3D printing data Accordingly, the process of preparing the metal powder (S200) and the process of melting and hardening the metal powder (S300) may be repeatedly performed.

In the method for manufacturing a shell for a mold according to an embodiment of the present invention, a process of preparing 3D printing data (S100) may be performed first.

The 3D printing data may contain structural information of the shell. 3D printing data may be composed of files, and may be recorded in various media in the form of files. The medium may be various storage devices such as CD-ROM and USB. The process of preparing 3D printing data may be carried out through production, processing, transfer, rental, copying, and online transmission of 3D printing data.

The structural information of the shell can be utilized as 3D printing data. Since the structure of the shell is used as data, the contact portion 100 can be easily designed to correspond to the shape of the casting 40 to be produced. In addition, the location and shape of the cooling channel 500 may be designed to be adjacent to the contact portion 100 .

By utilizing 3D printing data, manufacturing cost can be saved and manufacturing time can be reduced even when the casting 40 is produced in small quantities. In addition, even if there is a flaw in the design, it can be easily responded by simply modifying the 3D printing data.

In the method for manufacturing a shell for a mold according to an embodiment of the present invention, a process of preparing metal powder used as a material for the shell (S200) may proceed.

3D printing methods can be classified as follows according to the material supply method, material combination method, and the type and intensity of energy supplied. 3D printing methods include photo polymerization (PP), material extrusion (ME), binder jetting (BJ), material jetting (MJ), and high-energy direct irradiation (Direct Energy Deposition (DED), Power Bed Fusion (PBF), and Sheet Lamination (SL).

A preferred embodiment of the present invention may be performed as follows as a selective laser sintering (SLS) method among powder layer melting method (PBF).

The SLS method spreads powder flat on a powder bed using blades and rollers, selectively irradiates the laser on the thinly spread powder, and then spreads the powder thinly on it, flattens it, and selectively irradiates the laser on the thinly spread powder. according to the method

In the process of preparing the metal powder according to an embodiment of the present invention (S200), the metal powder 90 is thinly and flattened on a powder bed using a blade, a roller, or the like, as described above. At this time, the metal powder 90 corresponds to the material of the shell for the mold. The metal powder 90 may have a higher melting point than the molten metal 70 injected into the shell. In this case, it is possible to prevent the mold shell from melting by the injection of the molten metal 70 .

In the method for manufacturing a shell for a mold according to an embodiment of the present invention, a process of melting and curing the metal powder (S300) may proceed.

7 shows a shell manufacturing method according to an embodiment of the present invention.

Referring to FIG. 7 , when melting the metal powder 90, a high energy source 60 may be used. A laser may be mainly used, and an energy source such as an electron beam may be used. Taking a laser as an example, the laser may selectively irradiate the metal powder 90 to be melted, and the selected metal powder 90 may be melted and then hardened. As the new metal powder 90 is melted and then hardened on the previously hardened material, the newly hardened metal powder 90 may be combined with the previously hardened material.

The process of melting and hardening the metal powder 90 as described above may be performed in a chamber. Since there may be a problem of metal oxidation using the metal powder 90 and the high energy source 60, a chamber structure may be adopted to prevent metal oxidation and powder scattering. The chamber may be filled with a stable inert gas.

The shell manufactured in the shell manufacturing method for a mold according to an embodiment of the present invention is provided to correspond to the shape of the casting 40 and has a contact portion 100 having a contact surface with the material of the casting 40, the contact portion 100 A side wall portion 200 formed along an edge and extending downward, a bottom portion 300 provided at a lower end of the side wall portion 200 to form a bottom surface, and extending from the bottom portion 300 to the contact portion 100 It may include a plurality of support parts 400 and a cooling channel 500 formed adjacent to the contact part 100 to uniformly cool the material of the casting 40.

In addition, the shell may further include a thermal deformation prevention unit 600 located on an inner surface of the contact unit 100 to prevent deformation by the molten metal 70 forming the metal unit 700. there is.

In addition, the thermal deformation prevention part 600 includes a plurality of polygonal parts 610 that are repeatedly formed by sharing one corner with each other, and the polygonal parts 610 protrude from the inner surface of the contact part 100. can be made into a shape.

In addition, the cross section of the cooling channel 500 may have a lower half circular shape and an upper upper hat shape.

In addition, the cooling channel 500 may include a plurality of grooves formed in the longitudinal direction on an inner surface of the cooling channel 500 .

In addition, the bottom portion 300 may include at least one through hole 310 through which molten metal 70 may be injected or a riser may be connected.

Since the above-described configuration and effects of the configuration are the same as those described above, they will be omitted.

Subsequently, the process of preparing the metal powder (S200) and the process of melting and curing the metal powder (S300) may be repeatedly performed according to the 3D printing data.

When the process of preparing the metal powder (S200) and the process of melting and hardening the metal powder (S300) are performed, one layer of the shell may be formed. By repeatedly performing this process, a laminated structure of the shell may be formed, and the shell may be finally completed.

Specifically, the metal powder 90 is spread evenly on the powder bed using a blade or a roller, and laser is selectively irradiated to the thinly spread metal powder 90 . Again, the metal powder 90 is laid thinly on it, planarized, and the process of selectively irradiating the laser to the thinly laid powder is repeated.

Next, look at the mold manufacturing method.

8 shows a sequence of a mold manufacturing method according to an embodiment of the present invention.

Referring to FIG. 8 , a mold manufacturing method according to an embodiment of the present invention includes a mold manufacturing method having a mold shell according to claim 1, comprising: preparing the shell (S400); Injecting molten metal into the inner space formed by the shell (S500); and cooling the molten metal injected into the inner space (S600).

In the mold manufacturing method according to an embodiment of the present invention, the process of preparing the shell (S400) may proceed first. The shell is the same as the shell for the mold described above, and the shell may correspond to the shell for the mold according to all embodiments of the present invention. A detailed description will be omitted.

In the mold manufacturing method according to an embodiment of the present invention, a process of injecting molten metal into the inner space formed by the shell (S500) may proceed.

Referring to FIG. 9 , the bottom part 300 may be located on the upper part and the contact part 100 may be located on the lower part. The through hole 310 of the bottom part 300 may be provided with two or more. A metal injection unit may be connected to one through hole 310 and a riser may be connected to the other through hole 310 .

First, the shell may include an inner space, and the molten metal 70 in which the metal part 700 is melted may be injected into the inner space of the shell. The melting point of the metal part 700 may be lower than that of the metal powder 90, which is a material of the shell. This is to prevent the shell from being melted by the molten metal 70.

In addition, the riser is connected to the other through hole 310 to prevent shrinkage defects occurring while the molten metal 70 is cooled, and to release air inside the shell to the outside.

In the mold manufacturing method according to an embodiment of the present invention, a process of cooling the molten metal injected into the inner space (S600) may proceed.

In order to complete the manufacture of the mold, a process of cooling the molten metal 70 must be performed. The molten metal 70 may be injected into the shell and cooled, and the molten metal 70 may be cooled to form the metal part 700 . At this time, the shell forms the skeleton of the mold and the metal part 700 is formed around the skeleton, so that the mold according to the embodiment of the present invention can be manufactured.

Next, a casting manufacturing method using a mold will be described.

10 shows a sequence of a casting manufacturing method using a mold according to an embodiment of the present invention.

Referring to Figure 10, the casting manufacturing method using a mold according to an embodiment of the present invention, the step of preparing a first mold having a contact portion corresponding to the shape of one side of the casting (S1100); Preparing a second mold having a contact portion corresponding to the shape of the other side of the casting (S1200); forming a cavity by bringing the first mold and the second mold into contact with each other (S1300); Injecting the material of the casting into the cavity (S1400); Cooling the material of the casting (S1500); And separating the casting obtained in the cooling process from the first mold and the second mold (S1600); including, but the first mold 10 and the second mold 20 are claimed in claim 7 or claim 7 It may be a mold according to any one of 8.

In the casting manufacturing method using a mold according to an embodiment of the present invention, a process of preparing a first mold having a contact portion corresponding to the shape of one side of the casting may be performed (S1100) at the same time or at different times, A process of preparing a second mold having a contact portion corresponding to the shape of the other side of the casting (S1200) may proceed.

The first mold 10 and the second mold 20 may be molds according to any one of claims 7 or 8. However, it is not necessarily limited thereto, and the first mold 10 and the second mold 20 may be all molds according to the embodiment of the present invention described above. The first mold 10 may have a contact portion 100 corresponding to the shape of one side of the casting 40 . In addition, the second mold 20 may have a contact portion 100 corresponding to the shape of the other side of the casting 40 .

Since the left and right sides of the casting 40 may or may not have a symmetrical structure, the contact portion 100 of the first mold 10 and the contact portion 100 of the second mold 20 may have a symmetrical structure, It may not be symmetrical. At this time, the positions and shapes of the cooling channels 500 of the first mold 10 and the cooling channels 500 of the second mold 20 may also vary depending on the shape of the casting 40 .

In the casting manufacturing method using a mold according to an embodiment of the present invention, a process of forming a cavity by contacting the first mold and the second mold with each other (S1300) may proceed.

11 shows a state in which the cavity 30 is formed according to an embodiment of the present invention.

Referring to FIG. 11 , the first mold 10 and the second mold 20 may form a space corresponding to the shape of the casting 40 by the contact portion 100 by contacting each other. At this time, the space corresponding to the shape of the casting 40 may be referred to as the cavity 30 . The contact part 100 of the first mold 10 and the contact part 100 of the second mold 20 form the outer shape of the casting 40 to produce the casting 40 corresponding to both contact parts 100.

In the casting manufacturing method using a mold according to an embodiment of the present invention, after the process of injecting the casting material into the cavity (S1400) is performed, the process of cooling the casting material (S1500) may proceed.

The material of the casting 40 may be plastic or metal. Plastic or metal, which is a material of the casting 40, may be melted and injected into the cavity 30. Then, by cooling the material of the casting 40, the casting 40 can be shaped. Specifically, it will be described next.

In the casting manufacturing method using a mold according to an embodiment of the present invention, a process of separating the casting obtained in the subsequent cooling process from the first mold and the second mold (S1600) may proceed.

12 shows a state in which the casting 40 is separated from the mold according to an embodiment of the present invention.

Referring to FIG. 12 , when the material of the casting 40 is cooled and the shape is completed, it must be separated from the first mold 10 and the second mold 20 . At this time, the ejector pushes the casting 40 out of the mold, so that the casting 40 can be completely separated from the mold and the casting 40 can be completed.

Next, we look at the cooling process a little more.

According to an embodiment of the present invention, the cooling process may lower the temperature of the material of the casting 40 by passing cooling water through the cooling channel 500 .

In the case of the conventional machining method other than the 3D printing method, it is difficult to determine the location and shape of the cooling channel 500 according to the shape of the casting 40, Depending on the cooling rate, the manufacturing time increases, and the casting 40 may cause thermal deformation.

As described above, in the present invention, the contact surface is determined according to the shape of the casting 40, and the location and shape of the cooling channel 500 may be determined according to the shape of the contact surface. The cooling channels 500 formed adjacently along the contact surface can uniformly cool the entire outer appearance of the casting 40, thereby reducing manufacturing time and minimizing thermal deformation of the casting 40.

As described above, although it has been described with reference to preferred embodiments of the present invention, those skilled in the art can variously modify the present invention within the scope not departing from the spirit and scope of the present invention described in the claims below. Or it can be carried out by modifying.

10: first mold 20: second mold
30: cavity 40: casting
60: high energy source 70: molten metal
90: metal powder 100: contact
200: side wall part 300: bottom part
310: through hole 400: support
500: cooling channel 550: home
600: thermal deformation prevention part 610: polygonal part
700: metal part

Claims (14)

A contact portion provided to correspond to the shape of the casting and having a contact surface with the material of the casting;
a side wall portion formed along an edge of the contact portion and extending downward;
a bottom portion provided at a lower end of the side wall portion to form a lower surface;
a plurality of support parts extending from the bottom part to the contact part;
a cooling channel formed adjacent to the contact portion to uniformly cool the material of the casting; and
Including a thermal deformation prevention portion having a plurality of polygonal portions to prevent deformation by molten metal,
The plurality of polygonal parts are closed by being connected to the contact part at the upper end, and the lower end is open.
delete delete The method of claim 1,
The cross section of the cooling channel, the lower portion is made of a lower semicircular shape and the upper portion is made of a hat shape, the shell for the mold.
The method of claim 1,
The cooling channel includes a plurality of grooves formed in a longitudinal direction on an inner surface of the cooling channel, a shell for a mold.
The method of claim 1,
the bottom part,
A shell for a mold including at least one through hole through which molten metal can be injected or a riser can be connected.
In the mold,
a shell constituting a frame of the mold; and
Including; a metal part located in the inner space formed by the shell,
the shell,
A contact portion provided to correspond to the shape of the casting and having a contact surface with the material of the casting;
A side wall portion formed along an edge of the contact portion and extending downward;
A bottom portion provided at a lower end of the side wall portion to form a bottom surface;
A plurality of support portions extending from the bottom portion to the contact portion;
A cooling channel formed adjacent to the contact portion to uniformly cool the material of the casting, and
Including a thermal deformation prevention portion having a plurality of polygonal portions to prevent deformation by molten metal,
The plurality of polygonal parts are closed by being connected to the contact part at the upper end, and the lower end is open.
delete In the method for manufacturing a shell for a mold constituting a frame of a mold,
preparing 3D printing data containing structural information of the shell;
preparing metal powder used as a material for the shell; and
Including the process of melting and hardening the metal powder,
the shell,
A contact portion provided to correspond to the shape of the casting and having a contact surface with the material of the casting, a side wall portion formed along the edge of the contact portion and extending downward, a bottom portion provided at the lower end of the side wall portion to form a bottom, and the bottom portion A plurality of support parts formed extending from the contact part to the contact part, a cooling channel formed adjacent to the contact part to uniformly cool the material of the casting, and a plurality of polygons having an upper end connected to the contact part and closed and a lower end open. Including a thermal deformation prevention unit provided,
According to the 3D printing data, the process of preparing the metal powder and the process of melting and curing the metal powder are repeatedly performed, a method for manufacturing a shell for a mold.
delete The method of claim 9,
The cross section of the cooling channel, the lower portion is made of a lower semicircular shape and the upper portion is made of a hat shape, the shell manufacturing method for the mold.
In the mold manufacturing method having a mold shell according to claim 1,
preparing the shell;
injecting molten metal into the inner space formed by the shell; and
Including, the mold manufacturing method; the step of cooling the molten metal injected into the inner space.
Preparing a first mold having a contact portion corresponding to the shape of one side of the casting;
Preparing a second mold having a contact portion corresponding to the shape of the other side of the casting;
forming a cavity by bringing the first mold and the second mold into contact with each other;
injecting the casting material into the cavity;
cooling the material of the casting; and
Including; separating the casting obtained in the cooling process from the first mold and the second mold,
The first mold and the second mold are molds according to claim 7, casting manufacturing method using a mold.
The method of claim 13,
The cooling process is to pass cooling water through a cooling channel to lower the temperature of the material of the casting, casting manufacturing method using a mold.

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