Method for manufacturing molded article

Abstract

To provide a technique for satisfactorily forming a through-hole in a press-molded article.SOLUTION: In a method for manufacturing a molded article, a processing member is pressed using a first mold and a second mold to obtain a molded article having a through-hole. The first mold includes a first columnar part, and the second mold includes a second columnar part. The second columnar part is displaceable in a first direction with respect to the second mold. The method for manufacturing the molded article includes, before the first mold or the second mold is displaced to a bottom dead center or a top dead center, bringing an end part on the first direction side of the first columnar part and an end part on the second direction side of the second columnar part into an abutting state in which the end parts abut against each other, and pressing the processing member while maintaining the abutting state.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a method for manufacturing a press-formed product having a through hole. [Background technology]

[0002] The following Patent Document describes a method for manufacturing a molded product in which a first mold and a second mold are combined and a molten aluminum alloy is injected into the mold to perform die casting. The first mold and the second mold are provided with port forming portions that protrude from each mold and are used to form holes in the molded product. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-183082 Summary of the Invention [Problem to be solved by the invention]

[0004] Here, if a press-formed product is manufactured by pressing a fluid material using the first and second molds described in the patent document, the following problem may occur. That is, if the port forming portion comes into contact with the material while the first and second molds are approaching each other, pressure may be applied to the port forming portion, potentially causing the port forming portion to deform. If the port forming portion deforms, it may be difficult to properly form a hole in the press-formed product. This problem may occur not only when forming a hole in a press-formed product, but also when forming a through-hole in a press-formed product.

[0005] One aspect of the present disclosure provides a technique for successfully forming through holes in a press-molded product. [Means for solving the problem]

[0006] One aspect of the present disclosure is a method for manufacturing a molded product, in which a processed member is pressed using a first mold and a second mold arranged to face each other in the vertical direction to obtain a molded product having a through hole that penetrates in the vertical direction. The first mold has a first columnar portion. The second mold has a second columnar portion. The first columnar portion and the second columnar portion are members for forming the through hole and are columnar members having a length in the vertical direction. The first columnar portion is provided so as to protrude from a surface of the first mold facing the second mold in a first direction toward the second mold. The second columnar portion is provided so as to protrude from a surface of the second mold facing the first mold in a second direction toward the first mold. The first columnar portion and the second columnar portion are provided at positions facing each other. The second columnar portion is displaceable in the first direction relative to the second mold. The processed member is a member having flowability. The method for manufacturing the molded product includes placing a processed member between a first mold and a second mold; bringing the end of the first columnar portion on the first direction side into contact with the end of the second columnar portion on the second direction side before the first mold or the second mold is displaced to the bottom dead center or the top dead center; and, while maintaining the contact state, bringing the first mold and the second mold closer together until the first mold or the second mold is displaced to the bottom dead center or the top dead center, thereby pressing the processed member.

[0007] With this configuration, the processed member detours around the first columnar section and / or the second columnar section, forming a through hole. Furthermore, because the processed member is pressed while maintaining contact, the processed member is less likely to be pinched between the end of the first columnar section on the first direction side and the end of the second columnar section on the second direction side. Therefore, the through hole can be formed satisfactorily.

[0008] In one aspect of the present disclosure, the second mold may further include an elastic member having elasticity. The elastic member may be capable of pressing the second columnar portion in the second direction. With this configuration, the second columnar portion is pressed in the second direction by the elastic member, and therefore, after the abutting state is established, the second columnar portion can press against the first columnar portion. This makes it easier to stably maintain the abutting state.

[0009] In one aspect of the present disclosure, the processed member may be a semi-solidified metal material, a resin material, or a resin composite material. With this configuration, a molded product having a through hole can be obtained using the semi-solidified metal material, the resin material, or the resin composite material.

[0010] In one aspect of the present disclosure, the processed member may be a semi-solid aluminum material. According to this configuration, a molded product having a through hole can be obtained using the semi-solid aluminum material.

[0011] In one aspect of the present disclosure, when the contact state is reached, the combined length of the first columnar portion protruding in the first direction from the surface of the first mold facing the second mold and the second columnar portion protruding in the second direction from the surface of the second mold facing the first mold may be greater than the vertical length of the processed workpiece. With this configuration, the end of the first columnar portion on the first direction side and the end of the second columnar portion on the second direction side come into contact before the processed workpiece is pressed. This further reduces the likelihood of the flowing processed workpiece being pinched between the end of the first columnar portion on the first direction side and the end of the second columnar portion on the second direction side.

[0012] In one aspect of the present disclosure, the cross-sectional area of ​​the first columnar section in a cross section perpendicular to the first direction may increase toward the surface of the first mold facing the second mold. With this configuration, the first columnar section has a slope, making it easier to remove the molded product from the first columnar section. [Brief explanation of the drawings]

[0013] [Figure 1] Fig. 1A is a diagram schematically showing the arrangement step, Fig. 1B is a diagram schematically showing the contact step, Figs. 1C and 1D are diagrams schematically showing the pressing step, and Fig. 1E is a diagram schematically showing the detachment step. [Figure 2] FIG. 10 is a plan view of the first mold in the placement step. [Figure 3]3A to 3D are schematic diagrams illustrating a process for producing a molded product using a press molding apparatus in which the second mold does not include a second columnar portion. Fig. 3A is a diagram illustrating a placement step. Figs. 3B to 3D are diagrams illustrating a press step. [Figure 4] 4A to 4E are diagrams illustrating a case where a processed member is sandwiched between the upper end of a first columnar section and the lower end of a second columnar section. FIG. 4A is a diagram schematically illustrating the arrangement step. FIG. 4B is a diagram schematically illustrating the contact step. FIGS. 4C and 4D are diagrams schematically illustrating the pressing step. FIG. 4E is a diagram schematically illustrating the detachment step. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, exemplary embodiments of the present disclosure will be described with reference to the drawings. [1. Embodiment] [1-1. Configuration of press forming equipment] The press-molding apparatus 1 shown in FIGS. 1A to 1E is an apparatus for pressing a workpiece 10 to obtain a molded product having a through-hole that penetrates in the vertical direction.

[0015] An example of a molded product is a component to be installed in an automobile. The processed member 10 is a member having fluidity. More specifically, the processed member 10 is a member that is unlikely to deform under its own weight when placed on the first mold 2 in the placement step described below, but has fluidity to the extent that it deforms without cracking when pressed. The processed member 10 is in a non-fluid state when used as a molded product. More specifically, the processed member 10 becomes solidified when cooled after being pressed. In this embodiment, the processed member 10 is a semi-solid aluminum material. The processed member 10 is not limited to a semi-solid aluminum material, and may be another semi-solid metal material (magnesium, for example). The processed member 10 may also be a resin material or a resin composite material.

[0016] The press forming apparatus 1 includes a first mold 2 and a second mold 3. The first mold 2 and the second mold 3 are arranged so as to face each other in the vertical direction. In this embodiment, the first mold 2 is arranged at the bottom, and the second mold 3 is arranged at the top. Furthermore, by moving the second mold 3 in the vertical direction, press forming is performed by the first mold 2 and the second mold 3.

[0017] The first mold 2 shown in FIG. 2 is a metal member having a rectangular parallelepiped shape. The first mold 2 includes a first columnar portion 21. As shown in FIGS. 1A to 1E, the first columnar portion 21 is a member for forming a through hole, and is a columnar member having a length in the vertical direction. The first columnar portion 21 is provided so as to protrude from a first surface 22, which is the surface of the first mold 2 that faces the second mold 3, in a direction toward the second mold 3. In other words, the first columnar portion 21 is provided so as to protrude upward from the first surface 22. The first columnar portion 21 is fixed to the first mold 2. The first columnar portion 21 includes a tapered portion 23 and a first body portion 24.

[0018] The tapered portion 23 has a truncated cone shape that tapers from bottom to top. In other words, the tapered portion 23 is designed so that the cross-sectional area of ​​a cross section perpendicular to the vertical direction decreases from bottom to top. That is, the tapered portion 23 is configured so that the cross-sectional area of ​​a cross section perpendicular to the vertical direction increases as it approaches the first surface 22. Furthermore, the tapered portion 23 is designed so that the vertical length of the processed member 10 when the second mold 3 is displaced to the bottom dead center is approximately the same as the vertical length of the tapered portion 23. In other words, the portion of the first columnar portion 21 that comes into contact with the processed member 10 when the second mold 3 is displaced to the bottom dead center is designed so that the cross-sectional area of ​​a cross section perpendicular to the vertical direction decreases from bottom to top.

[0019] The first body portion 24 has a cylindrical shape and extends upward from the upper end of the tapered portion 23. The diameter of the first body portion 24 is approximately the same as the diameter of the tapered portion 23 at the upper end. The second mold 3 is a rectangular parallelepiped metal member having a box-like shape that is open at the bottom. The second mold 3 includes a second columnar portion 31, a storage portion 35, a communication portion 36, and an elastic member 37.

[0020] The second columnar section 31 is a member for forming a through hole, and is a columnar member having a length in the vertical direction. The second columnar section 31 is provided so as to protrude in a direction toward the first mold 2 from a second surface 32, which is the surface of the second mold 3 that faces the first mold 2. In other words, the second columnar section 31 is provided so as to protrude downward from the second surface 32.

[0021] The first surface 22 of the first mold 2 extends substantially horizontally, and the second surface 32 of the second mold 3 also extends substantially horizontally. The second mold 3 has a sidewall 44 extending downward from the edge of the second surface 32 of the second mold 3 and substantially perpendicular to the second surface 32. The sidewall 44 is provided so as to surround the edge of the second surface 32. In other words, a rectangular parallelepiped internal space 45 surrounded by the second surface 32 and the sidewall 44 is formed below the second surface 32. As shown in FIGS. 1B to 1D , when the second mold 3 is lowered, the first mold 2 is inserted into the internal space 45 of the second mold 3 so that the side surface of the first mold 2 faces the inner circumferential surface of the sidewall 44 of the second mold 3 with almost no gap between them. In other words, the molded product is formed in a shape surrounded by the first surface 22, the second surface 32, and the sidewall 44. The shape of the internal space 45 can be determined appropriately depending on the shape of the molded product.

[0022] The second columnar section 31 includes a head section 33 and a second body section . The head 33 has a disk-like shape. The second body 34 extends downward from the center of the head 33 and has a cylindrical shape. The diameter of the second body 34 is smaller than the diameter of the head 33. The diameter of the second body 34 is approximately the same as the diameter of the first body 24. The cross section of the second columnar section 31 in the axial direction is approximately T-shaped.

[0023] The first columnar section 21 and the second columnar section 31 are provided in positions facing each other. More specifically, the first columnar section 21 and the second columnar section 31 are arranged so that the upper end of the first columnar section 21 and the lower end of the second columnar section 31 face each other. In other words, the first body section 24 and the second body section 34 are arranged in positions where their respective central axes are aligned in the up-down direction and coincide with each other.

[0024] The accommodation section 35 is a space provided inside the second mold 3, and is a space for accommodating the elastic member 37. In this embodiment, the accommodation section 35 is a space having a cylindrical shape. The diameter of the accommodation section 35 is designed to be slightly larger than the diameter of the head section 33. In other words, the head section 33 is capable of moving up and down within the accommodation section 35. The accommodation section 35 is a space surrounded by a ceiling section 41, side sections 42, and a floor section 43.

[0025] The ceiling portion 41, the side portion 42, and the floor portion 43 are walls formed by part of the second mold 3. The ceiling portion 41 is a wall that defines the upper end portion of the storage portion 35. The side portion 42 is a wall that defines the circumferential end portion of the storage portion 35. The floor portion 43 is a wall that defines the lower end portion of the storage portion 35.

[0026] The storage section 35 and the internal space 45 are in communication with each other via a communication section 36. The communication section 36 is a hole extending from the second surface 32 of the second mold 3 to the lower end of the storage section 35. In other words, the communication section 36 is a hole that penetrates the floor section 43 in the vertical direction. The communication section 36 has a cylindrical shape. The diameter of the communication section 36 is designed to be smaller than the diameter of the head section 33 of the second columnar section 31 and slightly larger than the diameter of the second body section 34 of the second columnar section 31. In other words, the second body section 34 can move in the vertical direction through the communication section 36. As shown in FIG. 1A , when the second mold 3 is at the top dead center, the head section 33 of the second columnar section 31 abuts on the upper surface of the floor section 43, and the second body section 34 of the second columnar section 31 penetrates the communication section 36 and protrudes from the second surface 32.

[0027] The elastic member 37 is a member having elasticity, and in this embodiment, is a spring. Note that the elastic member 37 is not limited to a spring and may be, for example, a gas cushion. The elastic member 37 is disposed in the storage portion 35. The upper end of the elastic member 37 is fixed to the ceiling portion 41, and the lower end of the elastic member 37 is fixed to the head portion 33 of the second columnar portion 31. The elastic member 37 can press the second columnar portion 31 downward. The second columnar portion 31 can be displaced in the vertical direction by expansion and contraction of the elastic member 37, and the second columnar portion 31 protrudes from the second surface 32 of the second mold 3 or is accommodated in the storage portion 35. More specifically, the head portion 33 of the second columnar portion 31 moves up and down in the storage portion 35, and the second body portion 34 of the second columnar portion 31 protrudes from the communicating portion 36 or is accommodated in the communicating portion 36 and the storage portion 35.

[0028] In this embodiment, as shown in FIG. 1A, the second columnar portion 31 is in a protruding state before pressing begins, and as shown in FIGS. 1B to 1D, once it reaches an abutting state, it gradually transitions to a housed state. The protruding state is a state in which the second columnar portion 31 partially protrudes from the communicating portion 36 and the housing portion 35 due to the elastic force of the elastic member 37. More specifically, the protruding state is a state in which the lower end of the second columnar portion 31 protrudes from the second surface 32. The housed state is a state in which a force is applied to the second columnar portion 31 in a direction that pushes the second columnar portion 31 into the housing portion 35, causing the elastic member 37 to contract, and the second columnar portion 31 to be housed in the communicating portion 36 and the housing portion 35. More specifically, the housed state is a state in which the lower end of the second columnar portion 31 is housed in the communicating portion 36.

[0029] The abutting state is a state in which the upper end of the first columnar section 21 and the lower end of the second columnar section 31 are in contact with each other. Note that the abutting state is not limited to a state in which the upper end of the first columnar section 21 and the lower end of the second columnar section 31 are in close contact with each other. The abutting state also includes a state in which a part of the workpiece 10 is sandwiched between the upper end of the first columnar section 21 and the lower end of the second columnar section 31, as shown in FIG. 4D . In other words, the abutting state includes a state in which the lower end of the second columnar section 31 is directly or indirectly placed on the upper end of the first columnar section 21.

[0030] [1-2. Manufacturing methods for molded products] 1A to 1E, a method for manufacturing a molded product using the press molding apparatus 1 will be described. The method for manufacturing a molded product of this embodiment includes a placement step, a contact step, a pressing step, and a detachment step.

[0031] [1-2-1. Placement process] First, as shown in Fig. 1A, a processed member 10 is placed between a first mold 2 and a second mold 3. In this embodiment, the processed member 10 is placed on a first surface 22 of the first mold 2. At this time, the processed member 10 is in a semi-solidified state (in other words, a slurry).

[0032] [1-2-2. Contact process] 1B, the second mold 3 is lowered to bring the first mold 2 and the second mold 3 closer together. The second columnar portion 31 is lowered in conjunction with the second mold 3. Then, before the second mold 3 is displaced to the bottom dead center, the upper end of the first columnar portion 21 and the lower end of the second columnar portion 31 come into contact with each other.

[0033] When the abutting state is reached for the first time, there is a slight gap between the upper surface of the processed workpiece 10 and the second surface 32 of the second mold 3. In other words, when the abutting state is reached for the first time, the upper surface of the processed workpiece 10 is not yet in contact with the second surface 32 of the second mold 3. In other words, when the abutting state is reached, the total length of the length by which the first columnar portion 21 protrudes upward from the first surface 22 of the first mold 2 and the length by which the second columnar portion 31 protrudes downward from the second surface 32 of the second mold 3 is designed to be slightly larger than the vertical length of the processed workpiece 10.

[0034] [1-2-3. Pressing process] 1C and 1D, while maintaining the contact state, the second die 3 is further lowered until it is displaced to the bottom dead center, thereby pressing the processed workpiece 10. From the time when the contact state is first established until the second die 3 is displaced to the bottom dead center, the second columnar portion 31 is displaced upward relative to the second die 3. In other words, the second columnar portion 31 transitions from the protruding state to the housed state.

[0035] The processed member 10 is pressed by the first mold 2 and the second mold 3, and a molded product having a shape corresponding to the internal space 45 is formed. At this time, the processed member 10 bypasses the first columnar portion 21, thereby forming a through hole that penetrates in the vertical direction. In other words, the processed member 10 flows so as to surround the first columnar portion 21, and the through hole is formed. The shape of the through hole substantially matches the shape of the tapered portion 23. In this embodiment, a molded product having a rectangular shape in a plan view and a truncated cone-shaped through hole is formed.

[0036] As shown in FIG. 1D, when the second mold 3 is displaced to the bottom dead center, the lower end of the second columnar section 31 and the upper end of the first columnar section 21 are accommodated in the communicating section 36 while maintaining abutment therewith. [1-2-4. Desorption process] 1E, the second mold 3 is raised to the top dead center. At this time, the second columnar section 31 is pressed downward by the elastic member 37, and therefore transitions from the housed state to the protruding state. The molded product is then removed from the first mold 2.

[0037] [1-3.Effects] According to the embodiment described above in detail, the following effects can be obtained.

[0038] (1a) In the above embodiment, the second mold 3 is brought into contact with the workpiece 10 before it is displaced to the bottom dead center, and the contact state is maintained while the workpiece 10 is pressed. Furthermore, the workpiece 10 bypasses the first columnar portion 21, thereby forming a through hole penetrating the workpiece 10 in the vertical direction. According to this configuration, the workpiece 10 bypasses the first columnar portion 21 and forms a through hole at the same time that the workpiece 10 is pressed. In other words, the through hole can be formed simultaneously in the press working process. Therefore, the cycle time can be improved compared to a method for manufacturing a molded product in which the press working process and the through hole forming process are performed separately.

[0039] (1b) In the above embodiment, the second die 3 is provided with a second columnar portion 31 that can be displaced upward relative to the second die 3. Let us consider a case in which a molded product is manufactured using a press molding apparatus 100 in which the second die 3 does not have a second columnar portion 31, as shown in FIGS. 3A to 3D. The second die 103 of the press molding apparatus 100 is provided with a storage section 51. The storage section 51 is a hole for storing the first columnar portion 21 when the first die 2 is displaced to the top dead center. More specifically, the storage section 51 is a cylindrical space that extends upward from the second surface 32 of the second die 103. The vertical length of the storage section 51 is approximately the same as the vertical length of the first body portion 24 of the first columnar portion 21.

[0040] As shown in FIG. 3B, when the first mold 2 is raised and the first mold 2 and the second mold 103 are brought closer together, a portion of the processed member 10 may enter the storage section 51. If the first mold 2 is further raised while a portion of the processed member 10 remains in the storage section 51, the first columnar portion 21 cannot be stored in the storage section 51 by the thickness of the processed member 10 that has entered the storage section 51, as shown in FIG. 3D. In other words, the first mold 2 cannot be displaced to the top dead center. As a result, it becomes impossible to manufacture a molded product with the desired shape. Furthermore, if the first mold 2 is forcibly raised to the top dead center, the first columnar portion 21 may be deformed. If the first columnar portion 21 is deformed, a through hole cannot be formed satisfactorily.

[0041] If the press-forming apparatus 100 were designed so that the vertical length of the first columnar section 21 was much longer than the vertical length of the processed workpiece 10, the possibility of a portion of the processed workpiece 10 getting caught in the storage section 51 could be reduced. However, the length of the first columnar section 21 would increase the vertical length of the storage section 51 and the vertical length of the side wall 44 of the second mold 103, resulting in an increase in the size of the press-forming apparatus 100. Furthermore, when removing the molded product from the first columnar section 21, it would be necessary to lift the molded product by the length of the first columnar section 21, which could be a time-consuming process.

[0042] However, according to the configuration of the above embodiment, the second columnar portion 31 is disposed in the communicating portion 36, and therefore the second die 3 is displaced to the bottom dead center while maintaining the abutting state with the communicating portion 36 closed. Therefore, even if the vertical length of the first columnar portion 21 is smaller than the vertical length of the processed workpiece 10, it is difficult for a part of the processed workpiece 10 to enter the storage portion 35 or the communicating portion 36.

[0043] Also, consider a configuration in which the second mold 3 is at its bottom dead center when the abutting state is reached, i.e., a configuration in which the second columnar portion 31 is fixed to the second mold 3. In such a configuration, if the workpiece 10 is sandwiched between the upper end of the first columnar portion 21 and the lower end of the second columnar portion 31, there is a possibility that the second mold 3 will not be able to descend to the intended bottom dead center. Furthermore, if an attempt is made to forcibly lower the second mold 3 to the bottom dead center while the workpiece 10 is sandwiched between the upper end of the first columnar portion 21 and the lower end of the second columnar portion 31, there is a possibility that the first columnar portion 21 and the second columnar portion 31 will be broken, chipped, or deformed. If the first columnar portion 21 and the second columnar portion 31 are deformed, it will be impossible to form a through hole satisfactorily.

[0044] However, with the configuration of the above embodiment, because the pressing is performed while maintaining the abutting state, the processed workpiece 10 is less likely to be pinched between the upper end of the first columnar section 21 and the lower end of the second columnar section 31. Even if the processed workpiece 10 is pinched between the upper end of the first columnar section 21 and the lower end of the second columnar section 31, the second columnar section 31 is displaced upward relative to the second mold 3, making it less likely that unnecessary pressure will be applied to the first columnar section 21 and the second columnar section 31, and allowing the second mold 3 to descend to the bottom dead center. This makes it possible to prevent the first columnar section 21 and the second columnar section 31 from being deformed. This therefore makes it possible to successfully form through holes in the molded product.

[0045] (1c) The second mold 3 includes an elastic member 37 that can press the second columnar portion 31 downward. With this configuration, when the second mold 3 moves to the bottom dead center, separates from the first mold 2, and returns to the top dead center, the lower end of the second columnar portion 31 protrudes from the second surface 32. Even if a portion of the processed workpiece 10 becomes pinched between the upper end of the first columnar portion 21 and the lower end of the second columnar portion 31 during press working, as shown in FIGS. 4A to 4C , the elastic member 37 contracts by the thickness of the pinched processed workpiece 10, as shown in FIG. 4D , allowing the second mold 3 to be displaced to the bottom dead center. Furthermore, when the second mold 3 returns to the top dead center, the pinched processed workpiece 10 is pushed downward together with the second columnar portion 31 by the elastic member 37, as shown in FIG. 4E . Therefore, it is possible to prevent the workpiece 10 sandwiched between the upper end of the first columnar section 21 and the lower end of the second columnar section 31 from being left behind in the storage section 35 or the communication section 36.

[0046] (1d) The workpiece 10 is a semi-solid aluminum material. With this configuration, a molded product having a through hole can be obtained using the semi-solid aluminum material.

[0047] (1e) When the state transitions to the abutting state, the combined length of the length by which the first columnar portion 21 protrudes upward from the first surface 22 of the first mold 2 and the length by which the second columnar portion 31 protrudes downward from the second surface 32 of the second mold 3 is designed to be greater than the vertical length of the processed member 10. With this configuration, the upper end of the first columnar portion 21 and the lower end of the second columnar portion 31 abut against each other before the processed member 10 is pressed. This further prevents the flowing processed member 10 from being pinched between the upper end of the first columnar portion 21 and the lower end of the second columnar portion 31. Furthermore, the vertical length of each of the first columnar section 21 and the second columnar section 31 can be designed to be shorter than the vertical length of the workpiece 10. This allows the press-forming device 1 to be made smaller in size.

[0048] (1f) The portion of the first columnar portion 21 that comes into contact with the workpiece 10 when the second die 3 is displaced to the bottom dead center is designed so that the cross-sectional area of ​​the cross section perpendicular to the up-down direction decreases from bottom to top. With this configuration, the tapered portion 23 has a slope, making it easier to remove the molded product from the first columnar portion 21. Furthermore, because the through hole is formed in a tapered shape, the inner periphery of the through hole is less likely to rub against the first columnar portion 21 when the molded product is removed from the first columnar portion 21.

[0049] (1g) When the second mold 3 is displaced to the bottom dead center, the lower end of the second columnar portion 31 is accommodated in the communicating portion 36. If the lower end of the second columnar portion 31 were accommodated in the accommodating portion 35 when the second mold 3 is displaced to the bottom dead center, the axial direction of the second body portion 34 and the axial direction of the communicating portion 36 could be misaligned. Therefore, when the second columnar portion 31 is pushed out by the elastic member 37, the lower end of the second columnar portion 31 may not fit into the communicating portion 36. However, with the above-described configuration, the lower end of the second columnar portion 31 remains in the communicating portion 36, and the second columnar portion 31 is smoothly pushed out by the elastic member 37.

[0050] 1D, when the second mold 3 is held at bottom dead center, the boundary between the upper end of the first columnar section 21 and the lower end of the second columnar section 31 does not come into contact with the through hole. This prevents steps or the like that may occur at the boundary from forming in the through hole. In other words, it is possible to prevent a decrease in the precision of the through hole.

[0051] (1h) A rectangular parallelepiped internal space 45 surrounded by the second surface 32 and the side wall 44 is formed below the second surface 32 of the second mold 3. When the second mold 3 is lowered, the first mold 2 is inserted into the internal space 45 of the second mold 3. With this configuration, as shown in FIG. 1E, when the second mold 3 is returned to the top dead center, the molded product is placed on the first mold 2 without the side surface of the molded product abutting against the mold or the like. Therefore, the molded product can be more easily removed from the first mold 2 than when the side surface of the molded product abuts against the mold or the like.

[0052] [1-4. Correspondence] In the above embodiment, the upward direction corresponds to the first direction, and the downward direction corresponds to the second direction. 2. Other Embodiments Although the embodiments of the present disclosure have been described above, it goes without saying that the present disclosure is not limited to the above-described embodiments and can take on various forms.

[0053] (2a) In the above embodiment, a configuration has been described in which the press working is performed by the first mold 2 and the second mold 3 by moving the second mold 3 in the vertical direction. However, a configuration in which the press working is performed by the first mold 2 and the second mold 3 by moving the first mold 2 in the vertical direction may also be used. Specifically, in the abutting step, before the first mold 2 is displaced to the top dead center, an abutting state is established in which the upper end of the first columnar portion 21 and the lower end of the second columnar portion 31 are brought into abutting contact. Subsequently, in the pressing step, while maintaining the abutting state, the first mold 2 is further raised until the first mold 2 is displaced to the top dead center, and the processed workpiece 10 is pressed. From the time the abutting state is first established until the first mold 2 is displaced to the top dead center, the second columnar portion 31 is displaced upward relative to the second mold 3. Subsequently, in the releasing step, the first mold 2 is lowered to the bottom dead center.

[0054] (2b) In the above embodiment, a configuration in which the first mold 2 is disposed downward and the second mold 3 is disposed upward is exemplified. However, a configuration in which the first mold 2 is disposed upward and the second mold 3 is disposed downward may also be used. In other words, a configuration in which Figures 1A to 1E are turned upside down may also be used. In this case, the downward direction corresponds to the first direction and the upward direction corresponds to the second direction.

[0055] (2c) In the above embodiment, the second mold 3 is illustrated as having the elastic member 37. However, the second mold 3 does not have to have the elastic member 37. For example, the second columnar section 31 may be configured to transition from the housed state to the protruding state due to its own weight.

[0056] (2d) In the above embodiment, a configuration was exemplified in which, when the abutting state is transitioned to, the combined length of the length by which the first columnar portion 21 protrudes upward from the first surface 22 of the first mold 2 and the length by which the second columnar portion 31 protrudes downward from the second surface 32 of the second mold 3 is greater than the vertical length of the processed member 10. However, when the abutting state is transitioned to, the combined length of the length by which the first columnar portion 21 protrudes upward from the first surface 22 of the first mold 2 and the length by which the second columnar portion 31 protrudes downward from the second surface 32 of the second mold 3 may be approximately the same as the vertical length of the processed member 10, or may be shorter than the vertical length of the processed member 10. Even if the processed member 10 is pressed and flows before the upper end of the first columnar section 21 and the lower end of the second columnar section 31 come into contact with each other, and is sandwiched between the upper end of the first columnar section 21 and the lower end of the second columnar section 31, the sandwiched processed member 10 will be pushed downward as shown in FIG. 4E.

[0057] (2e) In the above embodiment, a configuration in which the first columnar section 21 and the second columnar section 31 have a cylindrical shape has been exemplified. However, the shapes of the first columnar section 21 and the second columnar section 31 are not limited to this. For example, the shapes of the first columnar section 21 and the second columnar section 31 may be polygonal columns, or may have a U-shaped cross section perpendicular to the vertical direction. The shapes of the first columnar section 21 and the second columnar section 31 can be determined appropriately to match the shape of the desired through hole. The shape of the communicating section 36 can also be determined appropriately to match the shapes of the first columnar section 21 and the second columnar section 31.

[0058] In the above embodiment, the second columnar section 31 includes a head section 33 and a second body section 34. However, the second columnar section 31 does not have to include a head section 33. In other words, the second columnar section 31 may be a single cylindrical member. In this case, the diameter of the storage section 35 may be substantially the same as the diameter of the communication section 36, and the upper end of the elastic member 37 may be fixed to the ceiling section 41, and the lower end of the elastic member 37 may be fixed to the second body section 34 of the second columnar section 31.

[0059] (2f) In the above embodiment, the first mold 2 has a rectangular parallelepiped shape, and the second mold 3 has a box-like shape. However, the first mold 2 may have a box-like shape, and the second mold 3 may have a rectangular parallelepiped shape. In other words, the first mold 2 may have a sidewall 44 that extends upward from the edge of the first surface 22 of the first mold 2, approximately perpendicular to the first surface 22. The sidewall 44 may be provided so as to go around the edge of the first surface 22.

[0060] (2g) In the above embodiment, the first mold 2 and the second mold 3 are brought close to each other and brought into contact with each other before the second mold 3 is displaced to the bottom dead center. However, the timing at which the upper end of the first columnar portion 21 and the lower end of the second columnar portion 31 are brought into contact with each other is not limited to this. For example, the first mold 2 and the second mold 3 may be brought into contact with each other before being brought close to each other. More specifically, the first columnar portion 21 and / or the second columnar portion 31 may be configured to be movable up and down independently of the first mold 2 and the second mold 3, without being linked to each other.

[0061] (2h) In the above embodiment, the first mold 2 and the second mold 3 are configured to include one each of the first columnar portion 21 and the second columnar portion 31. However, the number of first columnar portions 21 and second columnar portions 31 is not limited to this. There may be two or more first columnar portions 21 and second columnar portions 31.

[0062] (2i) In the above embodiment, an example was given of a configuration in which the cross-sectional area of ​​the tapered portion 23 in a cross section perpendicular to the up-down direction is designed to increase toward the first surface 22. However, this is not limited to the tapered portion 23, and the cross-sectional area of ​​the entire first columnar portion 21 in a cross section perpendicular to the up-down direction may be designed to increase toward the first surface 22.

[0063] (2j) The function of one component in the above embodiments may be distributed among multiple components, or the functions of multiple components may be integrated into one component. Also, part of the configuration of the above embodiments may be omitted. Furthermore, at least part of the configuration of the above embodiments may be added to or substituted for the configuration of another of the above embodiments.

[0064] [Technical idea disclosed in this specification] [Item 1] A method for manufacturing a molded product, in which a processed member is pressed using a first mold and a second mold that are arranged to face each other in a vertical direction to obtain a molded product having a through hole that penetrates in a vertical direction, the first mold has a first pillar portion, the second mold has a second pillar portion, the first columnar portion and the second columnar portion are members for forming the through hole and are columnar members having a length in the vertical direction, the first columnar portion is provided so as to protrude from a surface of the first mold facing the second mold toward a first direction which is a direction toward the second mold, the second columnar portion is provided so as to protrude from a surface of the second mold facing the first mold toward a second direction side which is a direction toward the first mold, the first columnar section and the second columnar section are provided at positions facing each other, the second columnar portion is displaceable toward the first direction relative to the second mold; the processed member is a member having fluidity, The manufacturing method of the molded product is as follows: placing the processed member between the first mold and the second mold; before the first die or the second die is displaced to the bottom dead center or the top dead center, an end of the first columnar portion on the first direction side and an end of the second columnar portion on the second direction side are brought into contact with each other; While maintaining the abutting state, the first die and the second die are moved closer to each other until the first die or the second die is displaced to the bottom dead center or the top dead center, thereby pressing the processed member; A method for producing a molded article, comprising:

[0065] [Item 2] A method for producing a molded article according to item 1, the second mold further includes an elastic member having elasticity, The method for manufacturing a molded product, wherein the elastic member is capable of pressing the second columnar portion toward the second direction.

[0066] [Item 3] A method for producing a molded article according to item 1 or 2, The method for manufacturing a molded product, wherein the processed member is a semi-solid metal material, a resin material, or a resin composite material.

[0067] [Item 4] A method for producing a molded article according to item 1 or 2, The method for manufacturing a molded product, wherein the workpiece is a semi-solid aluminum material.

[0068] [Item 5] A method for producing a molded article according to any one of items 1 to 4, a manufacturing method for a molded product, wherein, when the abutting state is transitioned to, the combined length of the length by which the first columnar portion protrudes in the first direction from the surface of the first mold facing the second mold and the length by which the second columnar portion protrudes in the second direction from the surface of the second mold facing the first mold is greater than the vertical length of the processed member.

[0069] [Item 6] A method for producing a molded article according to any one of items 1 to 5, A method for manufacturing a molded product, wherein the first columnar portion is configured so that the cross-sectional area of ​​a cross section perpendicular to the first direction increases as it approaches the surface of the first mold that faces the second mold. [Explanation of symbols]

[0070] 1,100...press molding device, 2...first mold, 3,103...second mold, 10...processed member, 21...first columnar portion, 22...first surface, 23...tapered portion, 24...first body portion, 31...second columnar portion, 32...second surface, 33...head portion, 34...second body portion, 35...storage portion, 36...communicating portion, 37...elastic member, 41...ceiling portion, 42...side portion, 43...floor portion, 44...side wall, 45...internal space, 51...storage portion.

Claims

1. A method for manufacturing a molded product, comprising pressing a processed member using a first mold and a second mold arranged to face each other in a vertical direction to obtain a molded product having a through hole passing through in a vertical direction, the first mold has a first pillar portion, the second mold has a second pillar portion, the first columnar portion and the second columnar portion are members for forming the through hole and are columnar members having a length in the vertical direction, the first columnar portion is provided so as to protrude from a surface of the first mold facing the second mold toward a first direction side which is a direction toward the second mold, the second columnar portion is provided so as to protrude from a surface of the second mold facing the first mold toward a second direction side which is a direction toward the first mold, the first columnar portion and the second columnar portion are provided at positions facing each other, the second pillar portion is displaceable toward the first direction relative to the second mold; the processed member is a member having fluidity, The manufacturing method of the molded product is as follows: placing the processed member between the first mold and the second mold; before the first die or the second die is displaced to the bottom dead center or the top dead center, an end of the first columnar portion on the first direction side and an end of the second columnar portion on the second direction side are brought into contact with each other; While maintaining the abutting state, the first die and the second die are moved closer to each other until the first die or the second die is displaced to the bottom dead center or the top dead center, thereby pressing the processed member; A method for producing a molded article, comprising:

2. A method for producing the molded article according to claim 1, the second mold further includes an elastic member having elasticity, The method for manufacturing a molded product, wherein the elastic member is capable of pressing the second columnar portion toward the second direction.

3. A method for producing the molded article according to claim 1 or claim 2, The method for manufacturing a molded product, wherein the processed member is a semi-solid metal material, a resin material, or a resin composite material.

4. A method for producing the molded article according to claim 1 or claim 2, The method for manufacturing a molded product, wherein the workpiece is a semi-solid aluminum material.

5. A method for producing the molded article according to claim 1 or claim 2, a manufacturing method for a molded product, wherein, when the abutting state is transitioned to, the combined length of the length by which the first columnar portion protrudes in the first direction from the surface of the first mold facing the second mold and the length by which the second columnar portion protrudes in the second direction from the surface of the second mold facing the first mold is greater than the vertical length of the processed member.

6. A method for producing the molded article according to claim 1 or claim 2, A method for manufacturing a molded product, wherein the first columnar portion is configured so that the cross-sectional area of ​​a cross section perpendicular to the first direction increases as it approaches the surface of the first mold that faces the second mold.

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