Three-dimensional shaping apparatus and casting mold shaping 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 modeling apparatus and a mold modeling method. [Background technology]

[0002] Japanese Patent No. 4374575 discloses a molding method in which a resin model is placed in a formwork and plaster is poured into the formwork to create a plaster mold. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 4374575 Summary of the Invention [Problem to be solved by the invention]

[0004] Recently, there has been a demand for better molding techniques.

[0005] The present disclosure aims to solve the above-mentioned problems. [Means for solving the problem]

[0006] A first aspect of the present disclosure is a three-dimensional modeling device that performs additive manufacturing, comprising: a table; a head that heats and ejects a thermoplastic modeling material to stack the thermoplastic modeling material onto the table; a squeegee that applies a slurry-like mold material to stack the mold material on the table; and a hardening promotion unit that promotes hardening of the mold material stacked on the table.

[0007] A second aspect of the present disclosure is a mold-making method for forming a mold, comprising: a first lamination step of laminating the thermoplastic molding material onto a table by heating and ejecting the thermoplastic molding material from a head of a three-dimensional modeling device; a second lamination step of laminating the mold material onto the table by applying a slurry mold material with a squeegee of the three-dimensional modeling device; and a hardening promotion step of promoting the hardening of the mold material laminated on the table by a hardening promotion unit of the three-dimensional modeling device. By repeating this lamination process, a molded object is additively molded on the table; and a step of melting the thermoplastic molding material in the molded object and discharging the molten thermoplastic molding material to obtain a mold made of the hardened mold material. Effect of the Invention

[0008] The present disclosure makes it possible to provide a good three-dimensional modeling apparatus and a mold modeling method. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic diagram of a three-dimensional modeling apparatus. [Diagram 2] 2A to 2E are schematic diagrams illustrating a method for laminating a thermoplastic molding material and a mold material. [Diagram 3] FIG. 3 is a flow chart of the mold forming process. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Recently, there is an increasing need for three-dimensional printing devices capable of forming complex shapes that are difficult to form using conventional casting or forging, and a wide range of applications for mass-produced metal parts manufacturing is required. However, the metal materials generally used in three-dimensional printing devices are more expensive than materials for mass production. In addition, the mechanical strength of the object may be lower than that of mass production methods, so this is addressed by using auxiliary devices to control the quality during printing or by slowing down the printing speed to improve the quality. Alternatively, it may be addressed by using materials with a different chemical composition from conventional metal materials. In addition, after the printing is completed, post-processing such as removing the printing support and heat treatment is also required. Therefore, the total printing time is long until a molded object with sufficient quality and mechanical strength is completed. As mentioned above, there is a problem that the cost of the molded object is high due to the high material cost and long printing time. In addition, from the perspective of realizing a sustainable society, the development of more advanced technologies such as molding objects using reusable materials is desired.

[0011] Conventionally, a method is known in which a molded object made of a resin molding material, which is less expensive than metal powder, is embedded and burned out in a mold material such as plaster used in casting, and then cast. In this method, the process of molding a model and the process of embedding the molded object in the mold material are performed in separate processes. According to the present disclosure, it is possible to mold a state in which the model is embedded in the mold material in a single process. In addition, it is possible to mold the model and the mold part using a material that is relatively easy to obtain and inexpensive. As a result, the present disclosure provides a three-dimensional printing device that enables casting of complex shapes that could not be obtained by conventional molding methods, and that allows three-dimensional molded objects to be obtained more inexpensively than before.

[0012] [One embodiment] [Configuration of 3D printing device] FIG. 1 is a schematic diagram of a three-dimensional modeling apparatus 10. The three-dimensional modeling apparatus 10 of this embodiment models a model of a casting by stacking thermoplastic modeling materials. The three-dimensional modeling apparatus 10 of this embodiment also stacks gypsum, which is a mold material, around the casting model to form a mold. Hereinafter, an object modeled using the stacked thermoplastic modeling materials and the stacked mold material may be referred to as a modeled object. When the modeled object is heated, the thermoplastic modeling material inside is melted. The molten thermoplastic modeling material is discharged from the modeled 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 taken out. It is preferable that the discharged thermoplastic modeling material is used again to form a model of the casting.

[0013] The thermoplastic molding material may be a fat or oil material such as a wax material. The thermoplastic molding material may be a thermoplastic resin including a vegetable resin such as polylactic acid. The mold material is preferably gypsum in a slurry form, but is not particularly limited thereto and may be appropriately selected.

[0014] The three-dimensional modeling apparatus 10 includes a head 12, a table 14, a mold material supply unit 16, a squeegee 18, a storage tank 20, a hardening acceleration unit 22, and a control device 34.

[0015] The head 12 discharges molten thermoplastic molding material, thereby layering the thermoplastic molding material on the table 14. The mold material supply unit 16 supplies slurry mold material onto the sub-table 15. The squeegee 18 spreads the mold material on the sub-table 15 and applies the mold material over the thermoplastic molding material, thereby layering the mold material on the table 14.

[0016] The storage tank 20 stores the thermoplastic molding material layered on the table 14 and the mold material layered on the table 14. The table 14 is movable vertically within the storage tank 20. The table 14 moves downward every time one layer of the thermoplastic molding material and the mold material is layered.

[0017] The hardening acceleration section 22 has a first temperature adjuster 24, a second temperature adjuster 26, and a blower 28. The first temperature adjuster 24 is provided on the table 14. The first temperature adjuster 24 may be a heater. The first temperature adjuster 24 heats the thermoplastic molding material layered on the table 14 and the mold material layered on the table 14, thereby accelerating the hardening of the mold material.

[0018] The first temperature regulator 24 controls the temperature of the heated thermoplastic molding material and the mold material to a predetermined temperature. For example, when the thermoplastic molding material is an oily material such as a wax or a wax material, the predetermined temperature is a temperature in the range of 30°C to 60°C, but is not limited thereto as long as it is equal to or lower than the melting temperature of the oily material.

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

[0020] If the temperature of the thermoplastic molding material is too low, the contact angle of the thermoplastic molding material with respect to the mold material becomes large, resulting in low wettability. As a result, the thermoplastic molding material does not adhere to the mold material. On the other hand, if the temperature of the thermoplastic molding material is too high, the contact angle with respect to the mold material becomes small, resulting in high wettability. This may cause the thermoplastic molding material to seep into the mold material. By controlling the temperatures of the thermoplastic molding material and the mold material to a predetermined temperature, it is possible to promote the hardening of the mold material while maintaining a state in which the thermoplastic molding material adheres appropriately to the mold material. This improves the accuracy of the molded object.

[0021] The second temperature regulator 26 is provided on a side 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. The upper temperature regulator 30 and the lower temperature regulator 32 heat the thermoplastic molding material layered on the table 14 and the mold material layered on the table 14, thereby promoting hardening of the mold material. The upper temperature regulator 30 and the lower temperature regulator 32 control the temperatures of the heated thermoplastic molding material and mold material to be predetermined temperatures.

[0022] The amount of heat output from the lower temperature regulator 32 may be smaller than the amount of heat output from the upper temperature regulator 30. Heat is more likely to remain in the thermoplastic molding material and mold material located at the bottom than in the thermoplastic molding material and mold material located at the top. Therefore, if the thermoplastic molding material located at the bottom is heated in the same way as the thermoplastic molding material located at the top, the thermoplastic molding material may melt and soak into the mold material. By lowering the amount of heat output from the lower temperature regulator 32 compared to the amount of heat output from the upper temperature regulator 30, it is possible to suppress the thermoplastic molding material from soaking into the mold material.

[0023] The lower temperature regulator 32 may be a cooler. The lower temperature regulator 32, which is a cooler, may cool the thermoplastic molding material and the mold material instead of heating them. Alternatively, a lower temperature regulator 32 that can appropriately perform heating and cooling may be provided.

[0024] The blower 28 dries the thermoplastic molding material and the mold material by blowing air onto the thermoplastic molding material layered on the table 14 and the mold material layered on the table 14. This promotes the hardening of the thermoplastic molding material and the mold material. The temperature of the air discharged from the blower 28 may be higher than the temperature of the air around the blower 28. The temperature of the air discharged from the blower 28 may be lower than the temperature of the air around the blower 28. The temperature of the air discharged 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 mold material supply unit 16, the squeegee 18, the first temperature regulator 24, the second temperature regulator 26 and the blower 28.

[0026] The control device 34 has a calculation unit 36 ​​and a storage unit 38. The calculation unit 36 ​​is a processor such as a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit). The calculation unit 36 ​​includes a control unit 40. The control unit 40 is realized by executing a program stored in the storage unit 38 in the calculation 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 a discrete device. The control unit 40 controls the head 12, the mold material supply unit 16, the squeegee 18, the first temperature regulator 24, the second temperature regulator 26, and the blower 28.

[0027] Furthermore, when the thermoplastic molding material and the mold material are changed, the control device 34 appropriately controls the temperature to an optimal level. As a result, even if the thermoplastic molding material and the mold material are changed, the thermoplastic molding material and the mold material are laminated at a temperature controlled to an appropriate level according to the characteristics of the thermoplastic molding material and the mold material, so that the precision of the molded object can be maintained.

[0028] The storage unit 38 is a computer-readable storage medium. The storage medium is composed of a volatile memory (not shown) and a non-volatile memory (not shown). The volatile memory is, for example, a random access memory (RAM). The non-volatile memory is, for example, a read only memory (ROM) or a flash memory. Data and the like are stored in, for example, the volatile memory. Programs, tables, maps, and the like are stored in, for example, the non-volatile memory. At least a part of the storage unit 38 may be provided in the above-mentioned processor, integrated circuit, etc. At least a part of the storage unit 38 may be mounted on a device connected to the three-dimensional printing apparatus 10 via a network.

[0029] [Layering method] 2A to 2E are schematic diagrams for explaining a method for laminating a thermoplastic molding material and a mold material. As shown in FIG. 2A, the head 12 discharges the thermoplastic molding material to laminate one layer of the thermoplastic molding material. Next, as shown in FIG. 2B, the mold material supply unit 16 supplies the mold material. In FIG. 2B, the mold material is supplied on top of the laminated mold materials, but the mold material may be supplied on top of the sub-table 15 shown in FIG. 1. Next, as shown in FIG. 2C, the squeegee 18 spreads the mold material and applies it over the mold material that has already been applied. As shown in FIG. 2D, the blower 28 blows air onto the thermoplastic molding material and the mold material after the squeegee 18 has passed, thereby dehumidifying the thermoplastic molding material and the mold material. When the squeegee 18 finishes spreading the mold material, one layer of the mold material is laminated as shown in FIG. 2E.

[0030] [Mold forming process] FIG. 3 is a flow chart of the mold forming process.

[0031] In step S1, the control unit 40 of the control device 34 executes a first layering step. Then, the process proceeds to step S2. In the first layering step, the control unit 40 controls the head 12 to eject the molten thermoplastic molding material from the head 12. As a result, the thermoplastic molding 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 sub-table 15. After that, the process proceeds to step S3.

[0033] In step S3, the control unit 40 executes a second lamination step. In the second lamination step, the control unit 40 controls the squeegee 18 to apply the mold material by the squeegee 18. As a result, the mold material is laminated on the table 14. Then, the process proceeds to step S4. By performing the lamination process in steps S1 to S3, one layer of thermoplastic molding material and mold material is laminated. During the lamination process, a hardening promotion step is continuously performed in which the first temperature regulator 24, the second temperature regulator 26, and the blower 28 promote hardening 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 manufactured object is heated to melt the thermoplastic molding material in the object. The object may be heated by the first temperature controller 24 and the second temperature controller 26. The object may be heated by a device different from the three-dimensional printing device 10. The heating step may be performed by a user.

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

[0037] In addition to the above disclosure, the following notes are also disclosed.

[0038] (Appendix 1) The three-dimensional modeling device (10) of the present disclosure is a three-dimensional modeling device that performs additive modeling, and includes a table (14), a head (12) that heats and ejects a thermoplastic modeling material to stack the thermoplastic modeling material on the table, a squeegee (18) that applies a slurry-like mold material to stack the mold material on the table, and a hardening accelerator (22) that accelerates hardening of the mold material stacked on the table. With this configuration, a good three-dimensional modeling device can be provided.

[0039] (Appendix 2) In the three-dimensional printing apparatus described in Appendix 1, the hardening promotion unit may be a first temperature adjuster (24) provided on the table, and the first temperature adjuster may heat the thermoplastic molding material layered on the table and the mold material layered on the table. With this configuration, the mold material layered on the table can be well hardened.

[0040] (Appendix 3) In the three-dimensional printing apparatus described in Appendix 1 or 2, the hardening promotion unit may be a blower (28) that blows air, and the blower may blow air onto the thermoplastic molding material stacked on the table and the mold material stacked on the table.

[0041] (Appendix 4) In the three-dimensional printing apparatus described in Appendix 1 or 2, a storage tank (20) is provided for storing the thermoplastic molding material stacked on the table and the mold material stacked on the table, and the hardening promotion unit is a second temperature regulator (26) provided on a side of the storage tank, and the second temperature regulator may heat the thermoplastic molding material stacked on the table and the mold material stacked on the table.

[0042] (Appendix 5) In the three-dimensional printing apparatus according to Supplementary Note 1 or 2, the thermoplastic printing material may be a wax material, a fat or oil containing a wax material, or a thermoplastic resin containing polylactic acid.

[0043] (Appendix 6) The mold-making method disclosed herein is a mold-making method for forming a mold, and includes a first lamination step of laminating a thermoplastic molding material onto a table by heating and ejecting the thermoplastic molding material from a head of a three-dimensional modeling device, a second lamination step of laminating the mold material onto the table by applying a slurry mold material with a squeegee of the three-dimensional modeling device, and a hardening promotion step of promoting the hardening of the mold material laminated on the table by a hardening promotion unit of the three-dimensional modeling device. By repeating this lamination process, a molded object is layered on the table, and a step of melting the thermoplastic molding material in the molded object and discharging the molten thermoplastic molding material to obtain a mold made of the hardened mold material.

[0044] (Appendix 7) In the mold forming method described in Appendix 6, the hardening promotion unit may be a first temperature regulator provided on the table, and in the hardening promotion step, the first temperature regulator may heat the thermoplastic molding material stacked on the table and the mold material stacked on the table.

[0045] (Appendix 8) In the mold forming method described in Appendix 6 or 7, the hardening promotion unit may be a blower that blows air, and in the hardening promotion step, the blower may blow air onto the thermoplastic molding material stacked on the table and the mold material stacked on the table.

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

[0047] Although the present disclosure has been described in detail, the present disclosure is not limited to the above-mentioned individual embodiments. Various additions, replacements, modifications, partial deletions, etc. are possible for these embodiments within the scope of the gist of the present disclosure, or within the scope of the gist of the present disclosure derived from the contents described in the claims and their equivalents. These embodiments can also be implemented in combination. For example, in the above-mentioned embodiments, the order of each operation and the order of each process are shown as examples, and are not limited to these. The same applies when numerical values ​​or formulas are used in the description of the above-mentioned embodiments. [Explanation of symbols]

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

Claims

1. A three-dimensional modeling apparatus for performing additive manufacturing, A table and a head for heating and discharging a thermoplastic molding material onto the table, the thermoplastic molding material being deposited thereon; a squeegee for applying a slurry of the mold material onto the table to stack the mold material; A hardening accelerator that accelerates hardening of the mold material stacked on the table; A three-dimensional printing apparatus comprising:

2. The three-dimensional modeling apparatus according to claim 1 , the hardening accelerator is a first temperature regulator provided on the table, The three-dimensional printing apparatus, wherein the first temperature adjuster heats the thermoplastic molding material layered on the table and the mold material layered on the table.

3. The three-dimensional modeling apparatus according to claim 1 or 2, The hardening accelerator is a blower that blows air, A three-dimensional printing apparatus, wherein the blower blows air onto the thermoplastic molding material layered on the table and the mold material layered on the table.

4. The three-dimensional modeling apparatus according to claim 1 or 2, a container for containing the thermoplastic molding material layered on the table and the molding material layered on the table; The hardening accelerator is a second temperature regulator provided on a side surface of the storage tank, The three-dimensional printing apparatus, wherein the second temperature regulator heats the thermoplastic molding material layered on the table and the mold material layered on the table.

5. The three-dimensional modeling apparatus according to claim 1 or 2, The thermoplastic modeling material is a wax material, an oil or fat containing a wax material, or a thermoplastic resin containing polylactic acid.

6. A method for forming a mold, comprising the steps of: a first lamination step of laminating a thermoplastic modeling material on a table by heating and discharging the thermoplastic modeling material from a head of a three-dimensional modeling device; a second lamination step of laminating the mold material on the table by applying a slurry-like mold material with a squeegee of the three-dimensional modeling apparatus; a hardening promotion step of promoting hardening of the mold material stacked on the table by a hardening promotion unit of the three-dimensional modeling apparatus; a lamination process for laminating a model on the table by repeating the lamination process; melting the thermoplastic molding material in the molded object and ejecting the molten thermoplastic molding material to obtain a mold made of the hardened mold material; The mold forming method includes the steps of:

7. The mold making method according to claim 6, the hardening accelerator is a first temperature regulator provided on the table, A mold molding method, wherein in the hardening promotion step, the first temperature adjuster heats the thermoplastic molding material layered on the table and the mold material layered on the table.

8. The mold making method according to claim 6 or 7, The hardening accelerator is a blower that blows air, A mold molding method, in which, in the hardening acceleration step, the blower blows air onto the thermoplastic molding material layered on the table and the mold material layered on the table.

9. The mold making method according to claim 6 or 7, the hardening accelerator is a second temperature adjuster provided on a side surface of a container that contains the thermoplastic molding material stacked on the table and the molding material stacked on the table, In the hardening promotion step, the second temperature regulator heats the thermoplastic molding material layered on the table and the mold material layered on the table.

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