Molded products
The molding die design with integrated air-filled gaps in the heat insulating layer addresses fluidity issues by reducing heat transfer, enhancing material flow and product quality.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- ADVICS CO LTD
- Filing Date
- 2024-12-25
- Publication Date
- 2026-07-07
Smart Images
Figure 2026113256000001_ABST
Abstract
Description
Technical Field
[0001] Embodiments of the present invention relate to molded products molded by a molding die.
Background Art
[0002] Conventionally, a molding die including a main body portion of a die member, a heat insulating layer provided on the surface of the main body portion, and a surface metal layer provided on the heat insulating layer is known. When a material of a molded product is supplied to the cavity of the molding die, the temperature of the surface metal layer rises in a short time, and the fluidity of the material is less likely to decrease. As the material of the heat insulating layer, resin is used (Patent Document 1).
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0004] Regarding the heat insulating layer of the molding die, there is room for improvement to improve the fluidity of the material flowing into the die as compared with the conventional heat insulating layer.
[0005] Therefore, the present invention has been made in view of the above, and provides a molded product molded by a molding die capable of improving the fluidity of the material flowing into the die.
Means for Solving the Problems
[0006] An embodiment of the present invention is, for example, a molded product formed by a molding die, the molding die comprising: a metal member provided with a flow path configured for the flow of a coolant; a surface metal layer having a surface configured to define a molding chamber in which the molded product is formed; and a heat insulating layer having a plurality of connecting parts that connect the metal member and the surface metal layer, respectively, and formed integrally with the surface metal layer, with a plurality of gaps between the plurality of connecting parts that contain air. Therefore, as an example, the heat insulating layer can suppress heat transfer from the surface metal layer to the metal member by the air contained in the plurality of gaps between the plurality of connecting parts. That is, the thermal conductivity of the heat insulating layer is reduced. Therefore, the heat insulating layer can reduce heat dissipation from the surface metal layer. That is, when material is supplied to the molding chamber, the temperature of the surface metal layer rises in a short time, and the solidification of the material is suppressed. Therefore, the heat insulating layer can improve the fluidity of the material flowing into the mold. [Brief explanation of the drawing]
[0007] [Figure 1] Figure 1 is a schematic cross-sectional view showing a molding die and a molded product according to the first embodiment. [Figure 2] Figure 2 is a schematic plan view showing a portion of the thermal insulation layer of the first embodiment. [Figure 3] Figure 3 is a diagram illustrating the fluidity of the material flowing into the molding die 1 according to the first embodiment. [Figure 4] Figure 4 is a schematic perspective view showing a portion of the insulation layer of the second embodiment. [Modes for carrying out the invention]
[0008] Embodiments will be described below with reference to the drawings. Note that in this specification, components and descriptions of such components may be expressed in multiple ways. The components and their descriptions are examples and are not limited by the expressions used herein. Components may also be identified by names different from those used herein. Furthermore, components may also be described by expressions different from those used herein.
[0009] In the following explanation, “suppress” is defined, for example, as preventing the occurrence of an event, effect, or influence, or reducing the degree of an event, effect, or influence.
[0010] Furthermore, directions are indicated in each diagram. The X, Y, and Z directions intersect (are orthogonal) to each other. An example of the first direction in which the core moves is the +Z direction. An example of the second direction, opposite to the first direction, is the -Z direction.
[0011] Figure 1 is a schematic cross-sectional view showing a molding die 1 and a molded product 2 according to the first embodiment. As shown in Figure 1, the molded product 2 is a thermoplastic resin molded product formed by a molding die 1, which is, for example, an injection molding die. In this embodiment, the case in which the molding die 1 is used for injection molding will be described as an example. Note that the molding die 1 may also be used for molding methods such as die casting.
[0012] The molding die 1 has a cavity mold 3 and a core mold 4. A molding chamber 5 is provided in the molding die 1.
[0013] In a molding die 1, the material 20 for the molded product 2 is supplied to the molding chamber 5, and the material 20 is solidified by cooling, thereby molding the molded product 2 in the molding chamber 5. For example, in a molding die 1, the molding chamber 5 is filled with molten thermoplastic resin material 20, and the molded product 2 is formed by cooling the material 20.
[0014] The cavity mold 3 comprises a metal member 31, a surface metal layer 32, and a heat insulating layer 33. The cavity mold 3 forms, for example, a recess in the molding die 1. Also, while the core mold 4 is the movable side of the molding die 1, the cavity mold 3 is the fixed side. The cavity mold 3 forms, for example, the outer surface of the molded product 2.
[0015] Multiple flow channels 311 are provided in the metal member 31. Each of the multiple flow channels 311 is formed, for example, in a substantially cylindrical shape. The multiple flow channels 311 are arranged in the X direction of the metal member 31. A coolant, such as cooling water, flows through the flow channels 311.
[0016] The molding die 1 lowers the temperature of the metal member 31 by allowing a refrigerant to flow through the flow path 311. The molding die 1 lowers the temperature of the material 20 in the molding chamber 5 through the surface metal layer 32 and the heat insulation layer 33 by lowering the temperature of the metal member 31.
[0017] The surface metal layer 32 has a surface 321. The surface 321 defines the molding chamber 5 when the cavity mold 3 and the core mold 4 are fitted together. Therefore, the surface metal layer 32 is located between the molding chamber 5 and the metal member 31. The surface metal layer 32 is thinner than the metal member 31.
[0018] The surface metal layer 32 is formed by additive manufacturing, for example, by the powder bed fusion method (PBF) using a 3D printer or the like. Note that the surface metal layer 32 may be formed by the directed energy deposition method (DED) or manufactured by other methods.
[0019] The heat insulation layer 33 is formed integrally with the surface metal layer 32 by PBF, for example. Note that the heat insulation layer 33 may be formed by DED or manufactured by other methods. The heat insulation layer 33 is located between the surface metal layer 32 and the metal member 31. The heat insulation layer 33 is thinner than the metal member 31. Details of the heat insulation layer 33 will be described later.
[0020] The core mold 4 includes a metal member 41, a surface metal layer 42, and a heat insulation layer 43. The core mold 4 forms, for example, the convex portion of the molding die 1. Also, the core mold 4 is located in the +Z direction of the cavity mold 3. The core mold 4 is, for example, the movable side that moves in the Z direction with respect to the cavity mold 3 of the molding die 1. The core mold 4 forms, for example, the inner surface opposite to the outer surface of the molded product 2.
[0021] A plurality of flow paths 411 are provided in the metal member 41. Each of the plurality of flow paths 411 is formed in a substantially cylindrical shape. The plurality of flow paths 411 are arranged side by side in the X direction of the metal member 41. A refrigerant such as cooling water flows through the flow path 411.
[0022] The molding die 1 lowers the temperature of the metal member 41 by allowing a refrigerant to flow through the flow path 411. The molding die 1 lowers the temperature of the material 20 in the molding chamber 5 through the surface metal layer 42 and the heat insulation layer 43 by lowering the temperature of the metal member 41.
[0023] The surface metal layer 42 has a surface 421. The surface 421 defines the molding chamber 5 when the cavity mold 3 and the core mold 4 are fitted together. For this reason, the surface metal layer 42 is positioned between the molding chamber 5 and the metal member 41. The surface metal layer 42 is thinner than the metal member 41.
[0024] The surface metal layer 42 is formed, for example, by PBF. Note that the surface metal layer 42 may be formed by DED or manufactured by other methods.
[0025] The heat insulation layer 43 is formed integrally with the surface metal layer 42 by, for example, PBF. Note that the heat insulation layer 43 may be formed by DED or manufactured by other methods. The heat insulation layer 43 is positioned between the surface metal layer 42 and the metal member 41. The heat insulation layer 43 is thinner than the metal member 41. Details of the heat insulation layer 43 will be described later.
[0026] The molding chamber 5 is a space between the surface 321 of the surface metal layer 32 of the cavity mold 3 and the surface 421 of the surface metal layer 42 of the core mold 4. The molding chamber 5 is, for example, a space that extends from the center in the X direction, bends outward in the +Z direction, and further bends the outer ends in the X direction. Note that the molding chamber 5 is not limited to this shape.
[0027] FIG. 2 is a plan view schematically showing a part of the heat insulation layer 33 of the first embodiment. In FIG. 2, the heat insulation layer 33 of the cavity mold 3 is described as an example, but the heat insulation layer 43 of the core mold 4 has the same configuration. Note that the heat insulation layer 43 of the core mold 4 may have a different configuration from the heat insulation layer 33 of the cavity mold 3.
[0028] As shown in Figure 2, the insulation layer 33 has multiple connection points 331. Furthermore, the insulation layer 33 is provided with multiple gaps 332.
[0029] Each of the multiple connecting parts 331 is formed, for example, as a columnar shape extending in the Z direction. The multiple connecting parts 331 are connected to each other, forming gaps 332 between them. Specifically, when six of the multiple connecting parts 331 are connected, a so-called honeycomb structure is formed, having hexagonal columnar gaps 332 extending in the Z direction.
[0030] Each of the multiple connecting portions 331 connects the metal member 31 to the surface metal layer 32. Specifically, since the surface metal layer 32 and the heat insulating layer 33 are integrally formed by the PBF, one end of the connecting portion 331 in the Z direction is integrally formed with the surface metal layer 32. The other end of the connecting portion 331 in the Z direction is integrated with the metal member 31 in the PBF, for example.
[0031] Multiple gaps 332 contain air. Other gases may also be contained in the multiple gaps 332. The multiple gaps 332 are collectively referred to as the air layer 34. Each of the multiple gaps 332 is airtightly closed by a metal member 31, a surface metal layer 32, and multiple connecting parts 331. These multiple gaps 332 do not necessarily have to be airtightly closed; for example, if each is surrounded by a metal member 31, a surface metal layer 32, and multiple connecting parts 331, it is advantageous for ensuring rigidity compared to an configuration that is not airtightly closed.
[0032] The airtightly sealed gaps 332 further contain, for example, metal particles 3310 that were not sintered when the multiple connection parts 331 and the surface metal layer 32 were formed by PBF. That is, the metal particles 3310 are the material for the surface metal layer 32 and the heat insulating layer 33. The particle size of the metal particles 3310 is, for example, 20 to 50 μm. The air in the gaps 332 exists between the multiple metal particles 3310. However, in cases where a manufacturing method or connection part shape is adopted that prevents the metal particles 3310, which are the material for the multiple connection parts 331 and the surface metal layer 32, from remaining in the multiple gaps 332, particles of other materials, i.e., particles other than the material, may be contained in the gaps. These particles other than the material are preferably those with low thermal conductivity.
[0033] Figure 3 is a diagram illustrating the fluidity of the material 20 flowing through the molding die 1 according to the first embodiment. In Figure 3, the thermal insulation layer 33 of the cavity mold 3 is used as an example, but the same applies to the thermal insulation layer 43 of the core mold 4. Note that the thermal insulation layer 43 of the core mold 4 may have a different configuration from the thermal insulation layer 33 of the cavity mold 3.
[0034] As shown in Figure 3, when the cavity mold 3 and the core mold 4 are fitted together, a molding chamber 5 is formed between the surface 321 of the surface metal layer 32 of the cavity mold 3 and the surface 421 of the surface metal layer 42 of the core mold 4. The molten material 20 is filled into the molding chamber 5 from the sprue of the molding die 1.
[0035] The thickness of the surface metal layer 32 is set to withstand the pressure when the material 20 is filled, but it is thinner than the metal member 31. Therefore, the heat capacity of the surface metal layer 32 is small. When the material 20 is filled into the molding chamber 5, the temperature of the surface 321 rises rapidly due to heat transfer from the material 20 to the surface metal layer 32.
[0036] Furthermore, since the heat insulating layer 33 is located between the surface metal layer 32 and the metal member 31, the heat transfer from the surface metal layer 32 to the metal member 31 can be reduced by the multiple gaps 332 (air layers 34) that contain air. In other words, the temperature of the surface metal layer 32 is maintained at a high temperature close to the temperature of the molten material 20. As a result, the surface metal layer 32 can suppress the decrease in the temperature of the material 20, and thus suppress the solidification of the material 20. Therefore, the heat insulating layer 33 can improve the fluidity of the material 20 flowing into the mold.
[0037] In the first embodiment described above, for example, the thermal insulation layer 33 can be made highly rigid because the multiple connection parts 331 form a honeycomb structure. In addition, the thermal insulation layer 33 can suppress heat transfer from the surface metal layer 32 to the metal member 31 by the air contained in the multiple gaps 334 between the multiple connection parts 331.
[0038] Furthermore, if the heat insulating layer 33 is made of resin, as in conventional molding dies, a process is required to join the heat insulating layer 33 to the metal member 31 and the surface metal layer 32. For example, a resin heat insulating layer 33 is placed between the metal member 31 and the member that will become the surface metal layer 32, and the heat insulating layer 33 is joined to the metal member 31 and the surface metal layer 32 by pressing. In addition, if necessary, the member that will become the surface metal layer 32 is cut to define the shape of the molding chamber 5. However, since the heat insulating layer 33 in this embodiment is formed integrally with the surface metal layer 32, the manufacturing process can be reduced.
[0039] The following describes a second embodiment in which the configuration of the insulation layer 33 differs from that of the first embodiment. In the second embodiment, the same configuration as in the first embodiment will not be described. Figure 4 is a schematic perspective view showing a part of the insulation layer 33 of the second embodiment. In Figure 4, the insulation layer 33 of the cavity type 3 is used as an example, but the insulation layer 43 of the core type 4 may have a similar configuration. The insulation layer 43 of the core type 4 may have a different configuration from the insulation layer 33 of the cavity type 3.
[0040] As shown in Figure 4, the insulation layer 33 has multiple connection points 333. Furthermore, the insulation layer 33 is provided with multiple gaps 334.
[0041] In this embodiment, the multiple connecting portions 333 form, for example, a gyroid structure. Each of the multiple connecting portions 333 connects the metal member 31 to the surface metal layer 32. Alternatively, the multiple connecting portions 333 may form a lattice structure or the like.
[0042] Multiple gaps 334 contain air. These gaps 334 are interconnected and extend to the outside of the molding die 1. The multiple gaps 334 are collectively referred to as the air layer 34.
[0043] The multiple connection parts 333 are formed integrally with the surface metal layer 32, for example, by PBF. Therefore, when the multiple connection parts 333 are manufactured by PBF, metal particles remain in the multiple gaps 334. However, since the gaps 334 communicate with the outside of the molding die 1, after the heat insulating layer 33 and the surface metal layer 32 are formed, the metal particles are discharged from the gaps 334, for example, by suction.
[0044] In the second embodiment described above, for example, the thermal insulation layer 33 can be made highly rigid because the multiple connection parts 333 form a gyroid structure. In addition, the thermal insulation layer 33 can expel metal particles generated during the formation of the multiple connection parts 333 to the outside so that they do not remain in the gaps 334. Furthermore, the thermal insulation layer 33 can suppress heat transfer from the surface metal layer 32 to the metal member 31 by the air contained in the multiple gaps 334 between the multiple connection parts 331.
[0045] As an example, a molded article according to at least one embodiment described above is a molded article formed by a molding die, the molding die comprising: a metal member provided with a flow path configured for the flow of a coolant; a surface metal layer having a surface configured to define a molding chamber in which the molded article is formed; and a heat insulating layer having a plurality of connecting parts that connect the metal member and the surface metal layer, respectively, and formed integrally with the surface metal layer, with a plurality of gaps between the plurality of connecting parts in which air is contained. Therefore, as an example, the heat insulating layer can suppress heat transfer from the surface metal layer to the metal member by the air contained in the plurality of gaps between the plurality of connecting parts. That is, the thermal conductivity of the heat insulating layer is reduced. Therefore, the heat insulating layer can reduce heat dissipation from the surface metal layer. That is, when material is supplied to the molding chamber, the temperature of the surface metal layer rises in a short time, and the solidification of the material is suppressed. Therefore, the heat insulating layer can improve the fluidity of the material flowing into the die. Because the fluidity of the molding die can be improved, the filling pressure can be reduced. Also, because the solidification of the material is suppressed, the transferability of the molded article can be improved. Furthermore, the molding die suppresses material solidification, thereby improving the weld strength of the molded product.
[0046] In the above molded product, for example, each of the multiple gaps is airtightly closed by a metal member, a surface metal layer, and multiple connecting parts. Therefore, for example, the multiple connecting parts are connected to each other, to the metal member, and to the surface metal layer in such a way that the gaps are airtightly closed. Consequently, the thermal insulation layer can be made highly rigid.
[0047] In the above molded product, metal particles are contained in multiple gaps, for example. Therefore, for example, the surface metal layer and the heat insulating layer can be easily fabricated using, for example, PBF, such that metal particles remain in the gaps. Furthermore, because the metal particles are not sintered together and are not in close contact with each other, the thermal conductivity of the heat insulating layer is unlikely to be high.
[0048] In the above molded product, for example, multiple gaps communicate with the outside of the molding die. Therefore, for example, the heat insulating layer can be discharged to the outside of the molding die so that metal particles that were not sintered during the formation of the surface metal layer and heat insulating layer in PBF do not remain in the gaps.
[0049] As an example, the above molded product has multiple connection points that form a gyroid structure. Therefore, as an example, the heat insulating layer can be made more rigid by having multiple connection points that form a gyroid structure, and metal particles that were not sintered during the formation of the connection points can be expelled to the outside so that they do not remain in the gaps. The heat insulating layer has a gyroid structure, which reduces stress concentration compared to, for example, a lattice structure.
[0050] Although embodiments of the present invention have been illustrated above, these embodiments and modifications are merely examples and are not intended to limit the scope of the invention. The above embodiments and modifications can be implemented in various other forms, and various omissions, substitutions, combinations, and changes can be made without departing from the spirit of the invention. Furthermore, the configurations and shapes of each embodiment and modification can be partially replaced. [Explanation of Symbols]
[0051] 1...Molding die, 2...Molded product, 5...Molding chamber, 31,41...Metal component, 32,42...Surface metal layer, 33,43...Insulation layer, 311,411...Flow channel, 321,421...Surface, 331,333...Connection part, 332,334...Gap, 3310...Metal particle.
Claims
1. A molded product formed by a molding die, The aforementioned molding die is A metal member having a flow path configured for the flow of a refrigerant, A surface metal layer having a surface configured to define a molding chamber in which the molded product is formed, A heat insulating layer having a plurality of connecting parts that connect the metal member and the surface metal layer, formed integrally with the surface metal layer, and having a plurality of gaps between the plurality of connecting parts that contain air, Equipped with, A molded product formed by the said molding die.
2. Each of the aforementioned gaps is airtightly closed by the metal member, the surface metal layer, and the aforementioned connection parts. The molded article according to claim 1.
3. Metal particles are contained in the aforementioned multiple gaps. The molded article according to claim 2.
4. The aforementioned multiple gaps communicate with the outside of the molding die. The molded article according to claim 1.
5. The aforementioned multiple connection parts form a gyroid structure. The molded article according to claim 4.