Molding method and molded product

Abstract

This invention provides a molding method that allows for the reduction of various costs, such as labor, time, and expenses, when molding molded products for construction and civil engineering by filling them with a hardening material. [Solution] Using a three-dimensional molding apparatus that creates a three-dimensional object by layering molten molding material, the following steps are performed: a mold molding step (step S1) in which a mold for the molded object is molded; a casting step (step S2) in which a hardening material is cast into the molded mold; a curing and hardening step (step S3) in which the cast hardening material is cured and hardened by heating with steam; and a demolding step (step S4) in which the hardened molded object is removed from the mold. In the above steps, the curing and hardening step is performed under conditions in which the mold is melted or softened by heating with steam, and the demolding step is performed in which a part of the mold is removed by melting or softening, or the molded object is removed from the melted or softened mold.

Description

Technical Field

[0001] This application discloses a molding method for molding a building and civil engineering molded product by filling a hardening material, and a molded product molded by such a molding method.

Background Art

[0002] In the molding of molded products such as construction members and structures by the precast concrete method, a method is used in which concrete is filled into a mold, sufficiently hardened while being cured, and then the mold is removed. As the mold used in such a precast concrete method, a steel mold is used. When molding a molded product with a complex design using such a steel mold, various costs such as time and cost increase, and there is a risk of reaching a non-realistic level. Therefore, Patent Document 1 discloses a method of forming a mold with a fiber-reinforced polymer composite material using a computer-controlled device and casting a highly designed building member.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the precast concrete method, various costs such as the work and cost of the process of removing the mold after casting become problems. In the method for casting a building member described in Patent Document 1, a method of melting the mold after casting is disclosed, but after curing and hardening, the entire mold is further heated and melted, resulting in an increase in various costs such as work, time, and cost.

[0005] This application has been made in view of such circumstances, and the main object is to disclose a molding method capable of reducing the cost of the process of removing the mold.

[0006] Furthermore, this application also aims to disclose molded articles formed by such molding methods. [Means for solving the problem]

[0007] To solve the above problems, the molding method disclosed in this application is a molding method for forming a molded product for construction and civil engineering by filling it with a hardening material, and uses a three-dimensional molding apparatus that builds a three-dimensional molded product by layering molten molding material, and performs a mold molding step for forming a mold for a molded product, a casting step for casting hardening material into the molded mold, a curing and hardening step for curing and hardening the cast hardening material by heating with steam, and a demolding step for demolding the hardened molded product from the mold, wherein the curing and hardening step is performed under conditions in which the mold melts or softens due to heating with steam, and the demolding step is characterized in that a part of the mold is removed by melting or softening, or the molded product is removed from the melted or softened mold.

[0008] Furthermore, in the molding method, the molding material comprises a first resin and a second resin having properties different from the first resin, and the melting or softening in the curing and hardening step is characterized by the melting or softening of the first resin contained in the mold.

[0009] Furthermore, in the molding method described above, the first resin is characterized in that it is a resin mainly composed of polycaprolactone.

[0010] Furthermore, in the molding method, the mold forming step is characterized by forming a mold by combining a first structural part whose main component is the first resin and a second structural part whose main component is the second resin.

[0011] Furthermore, in the molding method, the mold has a plurality of columnar sections extending in the vertical direction and wall sections connecting the columnar sections, wherein the columnar sections include the first structural section and the wall sections include the second structural section.

[0012] Furthermore, the molding method is characterized by further performing a recovery step of selecting and recovering the second structural part after demolding, and a reuse step of reusing the second resin, which is the main component of the recovered second structural part, as a molding material.

[0013] Furthermore, the molded product for construction and civil engineering disclosed in this application is characterized by being molded by the molding method described above. [Effects of the Invention]

[0014] The molding method and molded product disclosed in this application offer excellent advantages, such as reducing the cost of the demolding process by melting or softening the mold during the curing process, thereby facilitating demolding. [Brief explanation of the drawing]

[0015] [Figure 1] This is an explanatory diagram showing an example of the appearance of a three-dimensional molding apparatus used in the molding method disclosed in this application. [Figure 2] This is a conceptual diagram illustrating an example of the general shape and function of a nozzle in a three-dimensional molding apparatus used in the molding method disclosed in this application. [Figure 3] This flowchart shows an example of each step performed in the molding method disclosed in this application. [Figure 4] This is a conceptual diagram illustrating an example of the mold fabrication process performed by the molding method disclosed in this application. [Figure 5] This is a conceptual diagram illustrating an example of a casting process performed by the molding method disclosed in this application. [Figure 6] This is a conceptual diagram illustrating an example of a curing process performed in the molding method disclosed in this application. [Figure 7] This is a conceptual diagram illustrating an example of a demolding step performed in the molding method disclosed in this application. [Figure 8] This is a conceptual diagram illustrating an example of a reuse process performed in the molding method disclosed in this application. [Modes for carrying out the invention]

[0016] <Examples of Application> Hereinafter, the molding method of the present disclosure will be described while referring to the drawings. The molding method of the present disclosure is used, for example, for molding building and civil engineering molded articles by a construction method such as the precast concrete method. The molded articles for building and civil engineering in the present application are members and structures used for building or civil engineering. For example, they refer to members used for walls, floors, ceilings, columns, stairs, etc. of buildings, landscape materials, external structure materials, or a part or all of civil engineering structures such as tunnels, roads, bridges, and revetments, but are not limited thereto. Hereinafter, the molding method of the present disclosure will be described while referring to the drawings.

[0017] <Apparatus to be Used> FIG. 1 is an explanatory diagram showing an example of the external appearance of the three-dimensional modeling apparatus 1 used in the molding method of the present disclosure. The molding method of the present disclosure uses a three-dimensional modeling apparatus 1 such as a 3D printer. The three-dimensional modeling apparatus 1 is an apparatus that laminates molten modeling material 2 to form a three-dimensional molded article. The three-dimensional modeling apparatus 1 includes a main body apparatus 10, a control apparatus 11 for controlling the main body apparatus 10, and other configurations. The main body apparatus 10 illustrated in FIG. 1 includes various configurations such as an arm 12 having two bent portions and a nozzle formed at the tip of the arm 12. The main body apparatus 10 is controlled by a control apparatus 11 using a computer, and the control apparatus 11 controls operations of the arm 12 and ejection of the modeling material 2 from the nozzle 13 with respect to the main body apparatus 10.

[0018] The shaping material 2 preferably uses a resin for a 3D printer in the form of a low-melting-point filamentous resin, pelletized resin, or the like. Also, as the shaping material 2, a resin with properties such as water solubility may be used. The above-described shaping material 2 is an example, and as the shaping material 2, various resins and further other materials are used according to the application and the like. In the shaping method disclosed in the present application, the shaping material 2 uses a plurality of types of resins with different properties. In the present application, an example of an embodiment using a first resin 2a and a second resin 2b having different properties from the first resin 2a is disclosed. The first resin 2a is, for example, a resin having a lower melting point or softening point than the second resin 2b as a characteristic. As a specific example, the shaping material 2 mainly composed of low-melting-point polycaprolactone is used as the first resin 2a. The second resin 2b uses a shaping material 2 mainly composed of a resin such as general-purpose polycarbonate or polypropylene having a higher melting point (or softening point) than the first resin 2a. When the main component of the first resin 2a is a low-melting-point resin such as polycaprolactone, the first resin 2a undergoes modification such as melting by heating.

[0019] FIG. 2 is an explanatory diagram conceptually showing an example of the outline and function of a nozzle 13 provided in a three-dimensional shaping apparatus 1 used in the shaping method disclosed in the present application. Since the shaping method disclosed in the present application uses two types of melted resins, a dual-nozzle three-dimensional shaping apparatus 1 including a first nozzle 13a for supplying the first resin 2a and a second nozzle 13b for supplying the second resin 2b is used. FIG. 2(a) illustrates a nozzle 13 including the first nozzle 13a and the second nozzle 13b and having a single discharge hole. The nozzle 13 illustrated in FIG. 2(a) discharges the first resin 2a or the second resin 2b from a single discharge hole while switching the discharge of the first resin 2a from the first nozzle 13a and the discharge of the second resin 2b from the second nozzle 13b. FIG. 2(b) illustrates a nozzle 13 including the first nozzle 13a and the second nozzle 13b and having different discharge holes. The nozzle 13 illustrated in FIG. 2(b) discharges the first resin 2a from the first nozzle 13a and the second resin 2b from the second nozzle 13b from their respective discharge holes.

[0020] <Steps of the shaping method> Next, the steps performed in the molding method disclosed in this application will be described. Figure 3 is a flowchart showing an example of each step performed in the molding method disclosed in this application. The molding method disclosed in this application performs a mold making step (step S1) in which a mold frame 3 for a molded product 5 is formed by extruding molten molding materials 2 such as a first resin 2a and a second resin 2b from a nozzle 13 and layering them using a three-dimensional molding apparatus 1.

[0021] Figure 4 is a conceptual diagram illustrating an example of a mold fabrication process performed by the molding method disclosed in this application. Figure 4 illustrates a mold fabrication process in which a three-dimensional molding apparatus 1 extrudes molding material 2 to fabricate a mold 3 for a molded object 5 (see Figure 7, etc.) as a three-dimensional object. The molded object 5 formed by the mold 3 is a component or structure used for building or civil engineering, and Figure 4 illustrates the fabrication of a mold 3 for forming a rectangular molded object 5. The mold 3 illustrated in Figure 4 is assembled in a rectangular shape in plan view and is formed in a frame shape with wall portions 31 on all four sides in order to form a rectangular molded object 5. The four vertices of the rectangular shape in plan view are four (or more) column portions 30 extending in the vertical direction, and the four sides of the rectangle are wall portions 31 connecting the column portions 30. The column section 30 is formed as a first structural section whose main component is the first resin 2a, and the wall section 31 is formed as a second structural section whose main component is the second resin 2b. The formwork 3 is formed by combining the first structural section and the second structural section.

[0022] Returning to the flowchart in Figure 3, the molding method disclosed in this application involves a casting step (step S2) in which a hardening material 4 such as cement paste, mortar, or concrete is poured (filled) into the molded formwork 3.

[0023] Figure 5 is a conceptual diagram illustrating an example of a casting process performed by the molding method disclosed in this application. Figure 5 shows a casting process in which a hardening material 4 is poured into a formwork 3 that combines a column section 30, which is the first structural part, and a wall section 31, which is the second structural part.

[0024] Returning to the flowchart in Figure 3, the molding method disclosed in this application performs a curing and hardening step in which the cast hardened material 4 is cured and hardened (step S3).

[0025] Figure 6 is a conceptual diagram illustrating an example of a curing and hardening process performed in the molding method disclosed in this application. Figure 6 shows a curing and hardening process in which a hardening material 4 poured into a mold 3 is cured and hardened. The curing and hardening process is a process in which the hardening material 4 is cured by controlling the temperature and humidity to prevent drying of the hardening material 4 and to allow the hydration reaction to proceed. Various methods can be used for curing in the curing and hardening process, but the curing and hardening process illustrated in Figure 6 conceptually shows a form in which humidity and temperature are controlled using steam. The curing conditions in the curing and hardening process, for example, the temperature of the steam, are controlled to conditions that modify the first resin 2a, which is the main component of the first structural part constituting the mold 3. More specifically, the temperature of the steam that constitutes the curing conditions is controlled to a temperature at which the first resin 2a melts or softens and is modified. Therefore, in the curing and hardening process in the molding method disclosed in this application, as the curing and hardening of the hardening material 4 progresses, the modification of the mold 3, such as melting and softening, also progresses.

[0026] Returning to the flowchart in Figure 3, the molding method disclosed in this application performs a demolding step (step S4) in which the cured molded product 5 is removed from the mold 3. In the demolding step, the first structural part, which mainly consists of the first resin 2a that has undergone modification such as melting and softening in the curing and hardening step, is removed before demolding.

[0027] Figure 7 is a conceptual diagram illustrating an example of a demolding step performed in the molding method disclosed herein. Figure 7 shows the state after the first structural part, mainly composed of a first resin 2a containing low-melting-point polycaprolactone, has been melted and removed from the mold 3 by curing heating. In the demolding step, because part or all of the first structural part has melted due to the heating of steam during curing in the curing hardening step, the first structural part can be easily removed. By removing the first structural part, which is the column part 30, the second structural part, which is the wall part 31, can be removed, and the molded product 5 can be easily demolded from the mold 3.

[0028] Furthermore, in the molding method disclosed herein, since it is necessary to maintain the shape of the mold frame 3 while modifying the first resin 2a during the curing and hardening process, the mold frame 3 is configured in a shape that does not cause problems with hardening even if the first structural parts such as the column section 30 are removed. In addition, in the molding method disclosed herein, the conditions of the curing and hardening process and the demolding process may be adjusted in order to maintain the shape of the mold frame 3 so that no problems with hardening occur during the curing and hardening process. Specifically, in the molding method disclosed herein, instead of completely removing the first structural parts during the curing and hardening process, the first resin 2a may be heated to a temperature that softens as a modification of the first resin 2a, and the first structural parts or the entire mold frame 3 which have become easier to remove due to deterioration caused by softening may be removed. Furthermore, in the molding method disclosed herein, the temperature may be raised and reheated during the demolding process to melt the softened first resin 2a and demold it.

[0029] The molding method disclosed herein involves molding the molded product 5 as described above.

[0030] The molding method disclosed herein involves reusing the molding material 2 after molding the molded product 5. Returning to the flowchart illustrated in Figure 3, the molding method disclosed herein performs a recovery step (step S5) in which the second structural part is selected and recovered after demolding. In the recovery step, the second structural part that has retained its original shape despite being removed from the mold 3 in the demolding step illustrated in Figure 7 is selected and recovered. Selective recovery in step S5 means that only the second structural part that is in a reusable state is selected and recovered, excluding the first structural part or the first resin 2a from which the first structural part has melted.

[0031] The molding method disclosed herein involves a reuse step (step S6) in which the second resin 2b, which is the main component of the recovered second structural part, is reused as the molding material 2.

[0032] Figure 8 is a conceptual diagram illustrating an example of a reuse process performed by the molding method disclosed in this application. Figure 8 conceptually illustrates a reuse process in which the recovered second structural part is fed into a reuse device 6 to regenerate the second resin 2b, which is a pelletized resin. The reuse device 6 heats and melts the fed-in second structural part, purifies it to remove impurities, solidifies and molds it into pellets, and then extrudes the molded second resin 2b. The extruded second resin 2b is reused as a molding material 2 for the three-dimensional molding device 1.

[0033] The molding method disclosed herein further involves a step of regenerating the molding material 2 after the molding of the molded product 5 as described above.

[0034] The molding method disclosed in this application, as described above, is a molding method for molding a molded product 5 using a formwork 3 such as a precast concrete construction method. In the curing and hardening process, the formwork 3, in particular the first resin 2a which is the main component of the first structural part that constitutes a part of the formwork 3, is melted or softened by heating with steam for curing, making it easy to remove the formwork 3 in the demolding process. Therefore, the molding method disclosed in this application has excellent effects, such as being able to reduce various costs such as work, time, and expense in the demolding process for removing the formwork 3. Furthermore, since the molding method disclosed in this application uses a three-dimensional molding device 1 to form the formwork 3, it is possible to form a formwork 3 for molding a molded product 5 with a complex design, and even if the molded product 5 has a complex design, the formwork 3 can be easily removed, thus having excellent effects.

[0035] The present invention is not limited to the embodiments described above and can be implemented in various other forms. Therefore, the embodiments described above are merely illustrative in all respects and should not be interpreted restrictively. The technical scope of the present invention is described by the claims and is not restricted in any way by the text of the specification. Furthermore, any modifications and changes falling within the equivalent scope of the claims are all within the scope of the present invention.

[0036] For example, in the above embodiment, a configuration in which the column portion 30 is the first structural portion and the wall portion 31 is the second structural portion is shown, but the molding method disclosed in this application is not limited to this and can be developed into various configurations. For example, the molding method disclosed in this application can be developed into various configurations in which the first structural portion is provided near the midpoint of the column portions 30 at both ends of the wall portion 31, so that it can be divided near the center of a single wall portion 31.

[0037] Furthermore, although the above embodiment shows a method in which the first structural part is removed by heating, the molding method disclosed in this application is not limited to this and can be expanded to various methods of demolding by removing or degrading a part of the mold frame 3 through modification by curing. For example, in the molding method disclosed in this application, if a water-soluble resin is used as the first resin 2a, it is possible to remove or degrade a part of the mold frame 3 by dissolving the first resin 2a as modification by heated steam, thereby facilitating demolding in the demolding process. Moreover, although the above embodiment shows a method in which a part of the mold frame 3 is removed, the molding method disclosed in this application can be expanded to various forms, such as softening the entire mold frame 3 by heating to a degree that does not cause problems with hardening, and then removing the entire thing in the demolding process. [Explanation of symbols]

[0038] 1 3D printing equipment 10 Main unit 11 Control device 12 arms 13 nozzles 13a First nozzle 13b Second nozzle 2. Modeling materials 2a 1st resin 2b 2nd resin 3. Formwork (for molded objects) 30 Pillar section (first structure section) 31 Wall section (second structure section) 4 Curing material 5 Molded object 6 Reuse equipment

Claims

1. A molding method for forming molded products for construction and civil engineering by filling them with a hardening material, Using a three-dimensional molding device that creates three-dimensional objects by layering molten molding material, the process involves creating a mold for the molded object, and A casting process in which a hardening material is poured into the molded formwork, A curing and hardening process in which the cast material is cured and hardened by heating with steam, A demolding step in which the hardened molded product is removed from the mold, It is configured to execute, The curing and hardening process is carried out under conditions in which the formwork melts or softens due to heating by steam. The demolding step involves removing a portion of the mold by melting or softening, or removing the molded product from the melted or softened mold. A molding method characterized by the following:

2. The molding material comprises a first resin and a second resin having properties different from those of the first resin. The melting or softening in the curing and hardening process refers to the melting or softening of the first resin contained in the mold. The molding method according to feature 1.

3. The first resin is It is a resin whose main component is polycaprolactone. The molding method according to feature 2.

4. The aforementioned formwork fabrication process is, The mold is formed by combining a first structural part whose main component is the first resin and a second structural part whose main component is the second resin. The molding method according to feature 2.

5. The aforementioned formwork is Multiple columnar sections extending in the vertical direction, A wall connecting the aforementioned column sections and It has, The column portion includes the first structural portion, The wall portion includes the second structural portion. The molding method according to feature 4.

6. Furthermore, A recovery step for selecting and recovering the second structural part after demolding, A recycling process in which the second resin, which is the main component of the recovered second structural part, is reused as a molding material. Execute The molding method according to feature 4.

7. A molded product for construction and civil engineering, characterized by being molded by the molding method of claim 1 or claim 2.

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