Three-dimensional molding apparatus and mold manufacturing method

Abstract

SOLUTION: A three-dimensional shaping apparatus (10) for performing additive manufacturing includes: a table (14); a head (12) that heats and ejects a thermoplastic shaping material to laminate the thermoplastic shaping material on the table; a squeegee (18) that applies a mold material in a slurry form to laminate the mold material on the table; and a hardening acceleration unit (22) that accelerates hardening of the mold material laminated on the table.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a three-dimensional shaping apparatus and a mold shaping method.

Background Art

[0002] Japanese Patent No. 4374575 discloses a shaping method in which a resin mold is installed in a mold frame and gypsum is poured into the mold frame to create a gypsum mold.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Recently, better shaping technologies have been eagerly awaited.

[0005] The present disclosure aims to solve the above-described problems.

Means for Solving the Problems

[0006] A first aspect of the present disclosure is a three-dimensional shaping apparatus that performs layered shaping, including a table, a head that heats and discharges a thermoplastic shaping material to laminate the thermoplastic shaping material on the table, a squeegee that applies a slurry-shaped shaping material to laminate the shaping material on the table, and a curing acceleration unit that accelerates the curing of the shaping material laminated on the table.

[0007] A second aspect of the present disclosure is a mold manufacturing method for manufacturing a mold, comprising: a first layering step of layering thermoplastic molding material onto a table by heating and extruding the thermoplastic molding material from the head of a three-dimensional molding apparatus; a second layering step of layering the mold material onto the table by applying a slurry-like mold material with a squeegee of the three-dimensional molding apparatus; a curing acceleration step of accelerating the curing of the mold material layered on the table with a curing acceleration unit of the three-dimensional molding apparatus; and a step of obtaining a mold made of cured mold material by melting the thermoplastic molding material in the molded object and discharging the molten thermoplastic molding material. [Effects of the Invention]

[0008] This disclosure provides a good three-dimensional molding apparatus and a mold manufacturing method. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a schematic diagram of a three-dimensional printing device. [Figure 2] Figures 2A to 2E are schematic diagrams illustrating the lamination method of thermoplastic molding materials and mold materials. [Figure 3] Figure 3 is a flowchart of the mold manufacturing process. [Modes for carrying out the invention]

[0010] Recently, there has been a growing need for 3D printing equipment capable of creating complex shapes that are difficult to form using conventional casting and forging methods, and there is a demand for a wide range of applications in the mass production of metal parts. However, the metal materials used in 3D printing equipment are generally more expensive than those used for mass production. In addition, the mechanical strength of the printed object may be lower compared to mass production methods, so this is addressed by using auxiliary equipment to control quality during printing or by slowing down the printing speed to improve quality. Alternatively, this may be addressed by using materials with a different chemical composition than conventional metal materials. Furthermore, post-processing such as removing printing supports and heat treatment is required after printing is complete. As a result, the total printing time to produce a printed object with sufficient quality and mechanical strength becomes long. As described above, there is a problem that the cost of the printed object is high due to the high cost of materials and the long printing time. Also, from the perspective of realizing a sustainable society, the development of more advanced technologies, such as printing objects using reusable materials, is eagerly awaited.

[0011] Conventionally, a method has been known in which a molded object made from resin molding material, which is less expensive than metal powder, is embedded and burned into a mold material such as plaster used in casting, and then cast. In this method, the process of molding the model and the process of embedding the molded object in the mold material were performed in separate steps. According to this disclosure, it is possible to mold the model and the mold material in a single step. In addition, the model and the mold can be molded using relatively readily available and inexpensive materials. As a result, this disclosure provides a three-dimensional molding apparatus that enables the casting of complex shapes that could not be obtained with conventional molding methods, and that enables the production of three-dimensional objects at a lower cost than before.

[0012] [One Embodiment] [Configuration of a 3D printing device] Figure 1 is a schematic diagram of the three-dimensional molding apparatus 10. In this embodiment, the three-dimensional molding apparatus 10 creates a casting model by layering thermoplastic molding material. In addition, the three-dimensional molding apparatus 10 in this embodiment creates a mold by layering plaster, which is the mold material, around the casting model. Hereinafter, the object created by the layered thermoplastic molding material and the layered mold material may be referred to as the molded object. When the molded object is heated, the thermoplastic molding material inside melts. The molten thermoplastic molding material is discharged from the molded object, and a mold made of the mold material is completed. Molten metal or the like is poured into this mold, and after cooling, the mold is broken and the casting inside is removed. It is desirable that the discharged thermoplastic molding material be reused to form a casting model.

[0013] The thermoplastic molding material may be an oily material such as a wax or wax. The thermoplastic molding material may also be a thermoplastic resin containing a plant-based resin such as polylactic acid. The mold material is preferably a slurry-like gypsum, but is not particularly limited to this and can be selected as appropriate.

[0014] The three-dimensional molding apparatus 10 comprises a head 12, a table 14, a mold material supply unit 16, a squeegee 18, a storage tank 20, a curing accelerator unit 22, and a control device 34.

[0015] The head 12 discharges molten thermoplastic molding material, thereby accumulating the thermoplastic molding material on the table 14. The molding material supply unit 16 supplies slurry-like molding material onto the sub-table 15. The squeegee 18 spreads the molding material on the sub-table 15, layering it on top of the thermoplastic molding material, thereby accumulating the molding material on the table 14.

[0016] The storage tank 20 houses the thermoplastic molding material and the mold material stacked on the table 14. The table 14 is movable vertically within the storage tank 20. The table 14 moves downward each time a layer of thermoplastic molding material and mold material is stacked.

[0017] The curing acceleration part 22 includes a first temperature controller 24, a second temperature controller 26, and a blower 28. The first temperature controller 24 is provided on the table 14. The first temperature controller 24 may be a heater. By heating the thermoplastic modeling material laminated on the table 14 and the profile material laminated on the table 14 with the first temperature controller 24, the curing of the profile material is promoted.

[0018] The first temperature controller 24 is controlled so that the temperatures of the heated thermoplastic modeling material and the profile material become a predetermined temperature. For example, when the thermoplastic modeling material is a grease material such as a wax material or a rosin material, the predetermined temperature is in the range of 30°C to 60°C, but it is not limited to this as long as it is below the melting temperature of the grease material.

[0019] Also, when the thermoplastic modeling material is a thermoplastic resin containing a vegetable resin such as polylactic acid, it is desirable to control the temperature to about 50°C to 70°C so that the resin melted and softened by the head 12 adheres closely to the upper surface of the table 14. The predetermined temperature can be appropriately controlled according to the characteristics of the selected thermoplastic resin.

[0020] When the temperature of the thermoplastic modeling material is too low, the contact angle of the thermoplastic modeling material with respect to the profile material becomes large and the wettability becomes low. Therefore, the thermoplastic modeling material does not adhere to the profile material. On the other hand, when the temperature of the thermoplastic modeling material is too high, the contact angle with respect to the profile material becomes small and the wettability becomes high. As a result, there is a possibility that the thermoplastic modeling material may penetrate into the profile material. By controlling the temperature so that the temperatures of the thermoplastic modeling material and the profile material become a predetermined temperature, it is possible to maintain a state where the thermoplastic modeling material adheres moderately to the profile material while promoting the curing of the profile material. Thereby, the accuracy of the shaped object can be improved.

[0021] The second temperature regulator 26 is provided on the side surface of the storage tank 20. The second temperature regulator 26 has an upper temperature regulator 30 and a lower temperature regulator 32. The upper temperature regulator 30 may be a heater. The lower temperature regulator 32 may be a heater. By heating the thermoplastic modeling material laminated on the table 14 and the profile material laminated on the table 14 with the upper temperature regulator 30 and the lower temperature regulator 32, the curing of the profile material is promoted. The upper temperature regulator 30 and the lower temperature regulator 32 are controlled so that the temperatures of the heated thermoplastic modeling material and the profile material become a predetermined temperature.

[0022] Compared with the amount of heat output from the upper temperature regulator 30, the amount of heat output from the lower temperature regulator 32 may be small. The thermoplastic modeling material and the profile material located below are more likely to retain heat than the thermoplastic modeling material and the profile material located above. Therefore, when the thermoplastic modeling material located below is heated in the same manner as the thermoplastic modeling material located above, there is a risk that the thermoplastic modeling material will melt and penetrate into the profile material. By reducing the amount of heat output from the lower temperature regulator 32 with respect to the amount of heat output from the upper temperature regulator 30, penetration of the thermoplastic modeling material into the profile material can be suppressed.

[0023] The lower temperature regulator 32 may be a cooler. Instead of heating the thermoplastic modeling material and the profile material, the lower temperature regulator 32, which is a cooler, may cool them. Or, the lower temperature regulator 32 that can appropriately perform heating and cooling may be provided.

[0024] The blower 28 dries the thermoplastic modeling material laminated on the table 14 and the profile material laminated on the table 14 by blowing air from the blower 28 onto them. Thereby, the curing of the thermoplastic modeling material and the profile material is promoted. The temperature of the air sent out from the blower 28 may be higher than the temperature of the air around the blower 28. The temperature of the air sent out from the blower 28 may be lower than the temperature of the air around the blower 28. The temperature of the air sent out from the blower 28 may be the same as the temperature of the air around the blower 28.

[0025] The control device 34 controls the head 12, the material supply unit 16, the squeegee 18, the first temperature controller 24, the second temperature controller 26, and the blower 28.

[0026] The control device 34 has an arithmetic unit 36 ​​and a storage unit 38. The arithmetic unit 36 ​​is a processor such as a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit). The arithmetic unit 36 ​​includes a control unit 40. The control unit 40 is realized by the execution of a program stored in the storage unit 38 in the arithmetic unit 36. At least a part of the control unit 40 may be realized by an integrated circuit such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field-Programmable Gate Array). At least a part of the control unit 40 may be realized by an electronic circuit including discrete devices. The control unit 40 controls the head 12, the mold material supply unit 16, the squeegee 18, the first temperature controller 24, the second temperature controller 26, and the blower 28.

[0027] Furthermore, when the thermoplastic molding material and mold material are changed, the control device 34 appropriately controls the temperature. As a result, even when the thermoplastic molding material and mold material are changed, the thermoplastic molding material and mold material are laminated while being controlled to an appropriate temperature according to the characteristics of the thermoplastic molding material and mold material. Therefore, the accuracy of the molded object can be maintained.

[0028] The storage unit 38 is a computer-readable storage medium. The storage medium consists of volatile memory (not shown) and non-volatile memory (not shown). The volatile memory is, for example, RAM (Random Access Memory). The non-volatile memory is, for example, ROM (Read Only Memory), flash memory, etc. Data is stored in the volatile memory, for example. Programs, tables, maps, etc. are stored in the non-volatile memory, for example. At least a part of the storage unit 38 may be provided in the processor, integrated circuit, etc. mentioned above. At least a part of the storage unit 38 may be mounted on equipment connected to the three-dimensional molding device 10 by a network.

[0029] [Lamination Method] Figures 2A to 2E are schematic diagrams illustrating the method of laminating thermoplastic molding material and mold material. As shown in Figure 2A, the head 12 extrudes the thermoplastic molding material to laminate one layer of the thermoplastic molding material. Next, as shown in Figure 2B, the mold material supply unit 16 supplies the mold material. In Figure 2B, the mold material is supplied on top of the laminated mold material, but the mold material may also be supplied on the subtable 15 shown in Figure 1. Next, as shown in Figure 2C, the squeegee 18 spreads the mold material to apply another layer of mold material on top of the already applied mold material. As shown in Figure 2D, the blower 28 blows air onto the thermoplastic molding material and mold material after the squeegee 18 has passed through to dehumidify the thermoplastic molding material and mold material. Once the squeegee 18 has finished spreading the mold material, one layer of mold material is laminated as shown in Figure 2E.

[0030] [Mold forming process] Figure 3 is a flowchart of the mold manufacturing process.

[0031] In step S1, the control unit 40 of the control device 34 executes the first layering step. Then, the process moves to step S2. In the first layering step, the control unit 40 controls the head 12 to extrude the molten thermoplastic material from the head 12. As a result, the thermoplastic material is layered on the table 14.

[0032] In step S2, the control unit 40 controls the mold material supply unit 16 to supply the mold material to the subtable 15. Then, the process proceeds to step S3.

[0033] In step S3, the control unit 40 executes the second lamination step. In the second lamination step, the control unit 40 controls the squeegee 18 so that the mold material is applied by the squeegee 18. As a result, the mold material is laminated on the table 14. After that, the process proceeds to step S4. Through the lamination process performed in steps S1 to S3, one layer of thermoplastic molding material and mold material is laminated. While the lamination process is being performed, the first temperature controller 24, the second temperature controller 26, and the blower 28 continuously execute curing acceleration steps to accelerate the curing of the mold material.

[0034] In step S4, the control unit 40 determines whether or not the additive manufacturing of the object has been completed. If the control unit 40 determines that the additive manufacturing has been completed, the process proceeds to step S5. If the control unit 40 determines that the additive manufacturing has not been completed, the process returns to step S1.

[0035] In step S5, a heating step is performed. In the heating step, the additively fabricated object is heated to melt the thermoplastic material inside the object. The heating of the object may be performed by the first temperature controller 24 and the second temperature controller 26. The heating of the object may be performed by a device other than the three-dimensional printing apparatus 10. The heating step may be performed by the user.

[0036] In step S6, the removal step is performed. After that, the mold fabrication process is completed. In the removal step, the molten thermoplastic material is discharged from the fabricated object. The removal step may be performed by the user. This completes the mold.

[0037] In addition to the disclosures mentioned above, the following further notes are made:

[0038] (Note 1) The three-dimensional molding apparatus (10) of this disclosure is a three-dimensional molding apparatus that performs additive manufacturing and comprises a table (14), a head (12) that heats and extrudes a thermoplastic molding material to deposit the thermoplastic molding material onto the table, a squeegee (18) that applies a slurry-like molding material to deposit the molding material onto the table, and a curing accelerator (22) that accelerates the curing of the molding material deposited on the table. With such a configuration, a good three-dimensional molding apparatus can be provided.

[0039] (Note 2) In the three-dimensional molding apparatus described in Appendix 1, the curing acceleration unit is a first temperature controller (24) provided on the table, and the first temperature controller may heat the thermoplastic molding material and the mold material laminated on the table. With such a configuration, the mold material laminated on the table can be cured well.

[0040] (Note 3) In the three-dimensional molding apparatus described in Appendix 1 or 2, the curing accelerator is a blower (28) that sends out air, and the blower may blow air onto the thermoplastic molding material and the mold material laminated on the table.

[0041] (Note 4) In the three-dimensional molding apparatus described in Appendix 1 or 2, the apparatus is equipped with a storage tank (20) for storing the thermoplastic molding material and the mold material stacked on the table, and the curing accelerator is a second temperature controller (26) provided on the side of the storage tank, and the second temperature controller may heat the thermoplastic molding material and the mold material stacked on the table.

[0042] (Note 5) In the three-dimensional molding apparatus described in Appendix 1 or 2, the thermoplastic molding material may be a waxing agent, an oil containing a waxing agent, or a thermoplastic resin containing polylactic acid.

[0043] (Note 6) The mold manufacturing method of the present disclosure is a mold manufacturing method for manufacturing a mold, comprising: a first layering step of layering thermoplastic molding material onto a table by heating and extruding thermoplastic molding material from the head of a three-dimensional molding apparatus; a second layering step of layering the mold material onto the table by applying a slurry-like mold material with a squeegee of the three-dimensional molding apparatus; and a hardening acceleration step of accelerating the hardening of the mold material layered on the table by a hardening acceleration unit of the three-dimensional molding apparatus, by repeating the layering process to layer a molded object onto the table; and a step of obtaining a mold made of hardened mold material by melting the thermoplastic molding material in the molded object and discharging the molten thermoplastic molding material.

[0044] (Note 7) In the mold forming method described in Appendix 6, the curing acceleration unit is a first temperature controller provided on the table, and in the curing acceleration step, the first temperature controller may heat the thermoplastic forming material and the mold material laminated on the table.

[0045] (Note 8) In the mold forming method described in Appendix 6 or 7, the hardening accelerator is a blower that sends out air, and in the hardening accelerator step, the blower may blow air onto the thermoplastic forming material and the mold material stacked on the table.

[0046] (Note 9) In the mold forming method described in Appendix 6 or 7, the curing acceleration unit is a second temperature controller provided on the side of a storage tank that houses the thermoplastic molding material and the mold material stacked on the table, and in the curing acceleration step, the second temperature controller may heat the thermoplastic molding material and the mold material stacked on the table.

[0047] While this disclosure has been described in detail, it is not limited to the individual embodiments described above. These embodiments can be added, replaced, modified, partially deleted, etc., in any way that does not depart from the gist of this disclosure or from the spirit of this disclosure derived from the claims and their equivalents. These embodiments can also be implemented in combination. For example, the order of operations and processes in the embodiments described above are given as examples only and are not limited thereto. The same applies when numerical values ​​or mathematical formulas are used in the description of the embodiments described above. [Explanation of symbols]

[0048] 10...3D modeling machine 12...Head 14... Table 18... Squeegee 20...Storage tank 22...Curing accelerator 24…First temperature controller 26…Second temperature controller 28... Blower

Claims

1. A three-dimensional 3D printing apparatus that performs additive manufacturing, A table and, A head that heats and extrudes thermoplastic molding material to deposit the thermoplastic molding material onto the table, A squeegee is used to apply a slurry-like molding material, thereby stacking the molding material on the table, A hardening accelerator unit for accelerating the hardening of the mold material stacked on the table, A three-dimensional modeling device equipped with the following features.

2. In the three-dimensional molding apparatus according to claim 1, The curing acceleration unit is a first temperature controller provided on the table, A three-dimensional molding apparatus in which the first temperature controller heats the thermoplastic molding material and the mold material stacked on the table.

3. In the three-dimensional molding apparatus according to claim 1 or 2, The aforementioned hardening acceleration unit is a blower that sends out air, A three-dimensional molding apparatus in which the blower blows air onto the thermoplastic molding material and the mold material stacked on the table.

4. In the three-dimensional molding apparatus according to claim 1 or 2, The table is equipped with a storage tank for accommodating the thermoplastic molding material and the mold material stacked on the table, The curing acceleration unit is a second temperature controller provided on the side of the containment tank, A three-dimensional molding apparatus in which the second temperature controller heats the thermoplastic molding material and the mold material stacked on the table.

5. In the three-dimensional molding apparatus according to claim 1 or 2, The thermoplastic molding material is a waxing agent, an oil containing a waxing agent, or a thermoplastic resin containing polylactic acid, in a three-dimensional molding apparatus.

6. A method for forming a mold, A first layering step involves heating and extruding thermoplastic material from the head of a three-dimensional molding apparatus to layer the thermoplastic material onto a table, A second layering step involves applying a slurry-like mold material with a squeegee of the three-dimensional molding apparatus to the table, thereby layering the mold material on the table. A curing acceleration step in which the curing acceleration unit of the three-dimensional molding apparatus accelerates the curing of the mold material stacked on the table, The steps include: repeatedly performing a layering process to build an object on the table, The steps include: melting the thermoplastic molding material within the molded object and discharging the molten thermoplastic molding material to obtain a mold made of the hardened molding material; A mold forming method having the following characteristics.

7. In the mold forming method according to claim 6, The curing acceleration unit is a first temperature controller provided on the table, A mold forming method in which, in the curing acceleration step, the first temperature controller heats the thermoplastic forming material and the mold material stacked on the table.

8. In the mold forming method according to claim 6 or 7, The aforementioned hardening acceleration unit is a blower that sends out air, A mold forming method wherein, in the hardening acceleration step, the blower blows air onto the thermoplastic forming material and the mold material stacked on the table.

9. In the mold forming method according to claim 6 or 7, The curing accelerator is a second temperature controller provided on the side of a storage tank that houses the thermoplastic molding material and the mold material stacked on the table, A mold forming method wherein, in the curing acceleration step, the second temperature controller heats the thermoplastic forming material and the mold material stacked on the table.

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