Plasticizing device, three-dimensional modeling device, and injection molding device

Abstract

Provided is a plasticizing device that stably plasticizes a material, a three-dimensional modeling device, and an injection molding device. The plasticizing device includes a flat spiral member (40) having a groove forming surface (48) and a length in a rotational axis direction that is shorter than a length in a direction perpendicular to the rotational axis direction; a cylinder (50) having an opposing surface (52) that opposes the groove forming surface (48) and formed with a communication hole (56) that communicates with the opposing surface (52); and a heating portion (58) that heats a material supplied into a groove (42), wherein, in a region where the groove forming surface (48) and the opposing surface (52) oppose each other, a region in which a surface free energy of the groove forming surface (48) is lower than a surface free energy of the opposing surface (52) is present.

Description

Technical Field

[0001] This invention relates to a plasticizing device, a three-dimensional modeling device, and an injection molding device. Background Technology

[0002] Various plasticizing devices for plasticizing materials have been used throughout history. For example, Patent Document 1 discloses a plasticizing and discharging device comprising an impeller with spiral grooves and a barrel that abuts against the end face of the impeller at one end and has a material inflow channel open at the center.

[0003] In plasticizing apparatuses like the plasticizing and dispensing device in Patent Document 1, which have an impeller with a groove forming surface having a groove at one end in the direction of rotation, and a barrel with a connecting hole formed on an opposing surface opposite to the groove forming surface, there is a situation where the material cannot be stably plasticized. This is because the material being plasticized in the area opposite the groove forming surface and the opposing surface, as well as the plasticized material, adheres to the impeller side, making it difficult to supply to the connecting hole on the barrel side.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2010-241016 Summary of the Invention

[0005] A plasticizing apparatus of the present invention for solving the above-mentioned problems is characterized by comprising: a flat helical member capable of rotating about a rotation axis and having a groove forming surface having grooves, wherein the length of the flat helical member along the rotation axis is shorter than the length in a direction perpendicular to the rotation axis; a barrel having a counter surface opposite to the groove forming surface and having a connecting hole communicating with the counter surface; and a heating section for heating material supplied into the grooves, wherein the groove forming surface includes a region having a lower surface free energy compared to the surface free energy of the counter surface. Attached Figure Description

[0006] Figure 1 This is a schematic diagram of a three-dimensional modeling device having a plasticizing apparatus as an embodiment of the present invention.

[0007] Figure 2 To indicate Figure 1 A three-dimensional view of the outline structure of the lower surface of the flat spiral component of the three-dimensional modeling device.

[0008] Figure 3 To indicate Figure 1 A top-view summary of the upper surface of the barrel of the three-dimensional modeling device.

[0009] Figure 4This is a schematic diagram of an injection molding apparatus having a plasticizing device as an embodiment of the present invention. Detailed Implementation

[0010] First, a brief description of the present invention will be given.

[0011] The plasticizing apparatus of the first aspect of the present invention for solving the above-mentioned problems is characterized by comprising: a flat helical member capable of rotating about a rotation axis and having a groove forming surface having grooves, wherein the length of the flat helical member along the direction of the rotation axis is shorter than the length in a direction perpendicular to the direction of the rotation axis; a barrel having a counter surface opposite to the groove forming surface and having a connecting hole communicating with the counter surface; and a heating section for heating material supplied into the groove, wherein the groove forming surface includes a region having a surface free energy lower than that of the counter surface.

[0012] According to this method, in the region where the groove forming surface and the opposing surface face face, the surface free energy of the groove forming surface is lower than that of the opposing surface. By configuring it in this way, the material being plasticized in this region, and the plasticized material after plasticization, is less likely to adhere to the flat helical member compared to the barrel, thus making it easier for the material to reach the connecting hole. Therefore, it is possible to suppress the situation where the material becomes difficult to be supplied to the connecting hole on the barrel side, thereby enabling stable plasticization of the material.

[0013] The plasticizing apparatus of the second aspect of the present invention is characterized in that, in the first aspect, the groove forming surface has a first forming surface and a second forming surface, the second forming surface being located on a central side relative to the first forming surface, the opposing surface has a first opposing surface and a second opposing surface, the first opposing surface being opposite to the first forming surface, the second opposing surface being opposite to the second forming surface and located on a central side relative to the first opposing surface, the surface free energy of the first forming surface being lower than the surface free energy of the first opposing surface, and the surface free energy of the second forming surface being lower than the surface free energy of the second opposing surface.

[0014] According to this method, the surface free energy of the first forming surface is lower than that of the first opposing surface, and the surface free energy of the second forming surface is lower than that of the second opposing surface. By configuring the structure in this way, material is less likely to adhere to the flat helical member compared to the barrel in both the region where the groove forming surface and the opposing surface face each other (i.e., the region outside the first forming surface and the first opposing surface face each other, and the region at the center of the second forming surface and the second opposing surface face each other). Therefore, the material delivery force to the connecting hole can be increased in the region where the groove forming surface and the opposing surface face each other. Thus, for example, it is possible to injection mold the plasticized material from a small-diameter nozzle under high pressure.

[0015] The third-party plasticizing device of the present invention is characterized in that, in the first aspect, the groove forming surface has a first forming surface and a second forming surface, the second forming surface being located on the central side compared to the first forming surface, the opposing surface has a first opposing surface and a second opposing surface, the first opposing surface being opposite to the first forming surface, the second opposing surface being opposite to the second forming surface and located on the central side compared to the first opposing surface, the surface free energy of the first forming surface being lower than the surface free energy of the first opposing surface, and the surface free energy of the second forming surface being higher than the surface free energy of the second opposing surface.

[0016] According to this method, the surface free energy of the first forming surface is lower than that of the first opposing surface, and the surface free energy of the second forming surface is higher than that of the second opposing surface. By configuring it in this way, in the regions on the outer sides of the first forming surface and the first opposing surface, the material is less likely to adhere to the flat helical member compared to the barrel. Therefore, the material delivery force towards the connecting hole can be increased in the regions on the outer sides of the first forming surface and the first opposing surface, and the material can be slowly plasticized in the regions on the central sides of the second forming surface and the second opposing surface. Therefore, for example, a large-diameter nozzle can be used to injection mold the plasticized material with a larger injection volume.

[0017] The plasticizing apparatus of the fourth aspect of the present invention is characterized in that, in the first aspect, the groove forming surface has a first forming surface and a second forming surface, the second forming surface being located on a central side relative to the first forming surface, the opposing surface has a first opposing surface and a second opposing surface, the first opposing surface being opposite to the first forming surface, the second opposing surface being opposite to the second forming surface and located on a central side relative to the first opposing surface, the surface free energy of the first forming surface being higher than the surface free energy of the first opposing surface, and the surface free energy of the second forming surface being lower than the surface free energy of the second opposing surface.

[0018] According to this method, the surface free energy of the first forming surface is higher than that of the first opposing surface, and the surface free energy of the second forming surface is lower than that of the second opposing surface. By configuring it in this way, the material is less likely to adhere to the flat helical member compared to the barrel in the region on the central side where the second forming surface and the second opposing surface face each other. Therefore, the material can be slowly plasticized in the outer region where the first forming surface and the first opposing surface face each other, and the conveying force of the material toward the connecting hole can be increased in the region on the central side where the second forming surface and the second opposing surface face each other. Therefore, for example, it is possible to slowly and sufficiently plasticize a difficult-to-plasticize material in the outer region before injection molding.

[0019] The plasticizing apparatus of the fifth aspect of the present invention is characterized in that, in any one of the first to fourth aspects, a coating process or a cutting process is performed on at least one of the groove forming surface and the opposing surface.

[0020] According to this method, a coating process or a cutting process is performed on at least one of the groove forming surface and the opposing surface. Therefore, for example, the same material can be used to form the groove forming surface and the opposing surface, thereby increasing the variety of materials that can be used to manufacture flat helical parts and barrels.

[0021] The plasticizing apparatus of the sixth aspect of the present invention is characterized in that, in the fifth aspect, as the coating process, the opposing surface is subjected to at least one of diamond coating treatment, chromium coating treatment, or titanium coating treatment.

[0022] According to this method, the opposing surfaces are treated with at least one of diamond coating, chromium coating, or titanium coating. Therefore, it is possible to easily and durablely form opposing surfaces with high surface free energy.

[0023] The plasticizing apparatus of the seventh aspect of the present invention is characterized in that, in the fifth or sixth aspect, the groove forming surface is subjected to a fluorine coating treatment as part of the coating process.

[0024] According to this method, the trench forming surface is treated with a fluorine coating. Therefore, it is possible to easily form a trench forming surface with particularly low surface free energy.

[0025] The plasticizing apparatus of the eighth aspect of the present invention is characterized in that, in any one of the first to seventh aspects, the material comprises at least one of metal particles and ceramic particles.

[0026] According to this method, the material comprises at least one of metal particles and ceramic particles. Although using a material comprising at least one of metal particles and ceramic particles makes it particularly easy for the material to adhere to the side of the flat auger, it is possible to suppress the material from adhering to the side of the flat auger even in this case, thereby preventing the material from becoming difficult to feed into the connecting hole on the barrel side.

[0027] The plasticizing apparatus of the ninth aspect of the present invention is characterized in that, in any one of the first to eighth aspects, the difference in surface free energy in the region where the surface free energy of the groove forming surface is lower than that of the opposing surface is 4.6 mJ / m 2 above.

[0028] According to this method, the difference in surface free energy in the region where the surface free energy of the trench forming surface is lower than that of the opposing surface is 4.6 mJ / m. 2 That's all. By designing the structure in this way, it is possible to particularly effectively suppress situations where material becomes difficult to be supplied to the connecting holes on the barrel side, thereby enabling stable plasticization of the material.

[0029] The three-dimensional modeling apparatus of the tenth aspect of the present invention is characterized by comprising: a nozzle that ejects the material plasticized by a plasticizing apparatus of any one of the first to ninth aspects; and a worktable that supports the material ejected from the nozzle.

[0030] According to this method, it is possible to stably shape three-dimensional objects using plasticized materials.

[0031] The injection molding apparatus of the eleventh aspect of the present invention is characterized by comprising: a nozzle that ejects the material plasticized by any one of the first to ninth aspects of the plasticizing apparatus; and a fixing part that fixes a molding die that receives the material ejected from the nozzle.

[0032] According to this method, it is possible to reliably use the plasticized material for injection molding.

[0033] Three-dimensional modeling device (plasticizing device)

[0034] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. First, referring to... Figures 1 to 3 The overall structure of a three-dimensional modeling device 100 according to one embodiment of the present invention will be described. Furthermore, the following figures are schematic diagrams, showing some structural components omitted or simplified. In addition, in each figure, the X-axis direction is the horizontal direction, the Y-axis direction is the horizontal direction orthogonal to the X-axis direction, and the Z-axis direction is the vertical direction.

[0035] The 3D modeling apparatus 100 includes a control unit 101 for controlling the 3D modeling apparatus 100, a modeling unit 110 for generating and ejecting modeling material, a modeling stage 210 for serving as a base for the 3D model, and a moving mechanism 230 for controlling the ejection position of the modeling material. Under the control of the control unit 101, the modeling unit 110 ejects a modeling material, which is made from a solid material, into a paste-like form, onto the stage 210. The modeling unit 110 includes a material supply unit 20, which serves as a supply source for raw material MR before it is converted into modeling material; a modeling material generating unit 30, which converts the raw material MR into modeling material; and an ejection unit 60, which ejects the modeling material. That is, the 3D modeling apparatus 100 of this embodiment can be regarded as a plasticizing apparatus for plasticizing material. Furthermore, since the 3D modeling apparatus 100 includes a plasticizing apparatus composed of a material supply unit 20 and a modeling material generating unit 30, it can also be regarded as an apparatus for ejecting material (modeling material) plasticized by the plasticizing apparatus from the ejection unit 60 to model a 3D model. Here, "plasticization" is a concept that includes melting. In the case of a material with a glass transition temperature, it means heating the material above the glass transition temperature to make it flowable. In the case of a material without a glass transition temperature, it means heating the material above the melting point to make it flowable.

[0036] The material supply unit 20 supplies the raw material MR for generating the modeling material to the modeling material generating unit 30. The material supply unit 20 is, for example, a hopper for storing the raw material MR. The material supply unit 20 has a discharge port at its lower part. This discharge port is connected to the modeling material generating unit 30 via a connecting channel 22. The raw material MR is fed into the material supply unit 20 in the form of granules or powder.

[0037] The molding material generating unit 30 melts the raw material MR supplied from the material supply unit 20 to generate a fluid, paste-like molding material, which is then guided to the ejection unit 60. The molding material generating unit 30 includes a spiral housing 31, a motor 32, a flat spiral 40, and a barrel 50.

[0038] Figure 2 This is a perspective view showing the outline structure of the groove forming surface 48 side of the flat helical member 40. For ease of understanding of the technology, Figure 2 The flat helical element 40 shown is used to... Figure 1 The positional relationship between the upper surface 47 and the groove forming surface 48, which serves as the lower surface, is represented by them being opposite each other in the vertical direction. Figure 3This is a schematic top view showing the opposing surface 52 of the upper surface of the barrel 50. The flat helix 40 has a generally cylindrical shape with a height less than its diameter in the axial direction along its central axis. In other representations, the flat helix 40 is capable of rotating about a rotation axis RX along the Z-axis direction, and its length in the rotation axis direction is shorter than its length in the direction perpendicular to the rotation axis direction.

[0039] The flat helical component 40 is housed within the helical component housing 31. The upper surface 47 of the flat helical component 40 is connected to the motor 32, and the flat helical component 40 rotates within the helical component housing 31 by the rotational driving force generated by the motor 32. The motor 32 is driven under the control of the control unit 101.

[0040] A groove 42 is formed on the groove forming surface 48 of the flat helical member 40, which is the surface intersecting the rotation axis RX. The communication channel 22 of the material supply section 20 communicates with this groove 42 from the side of the flat helical member 40. Figure 2 As shown, in this embodiment, the grooves 42 are separated by the protrusions 43, forming three grooves. However, the number of grooves 42 is not limited to three; it can be one, or even two or more.

[0041] The groove forming surface 48 of the flat helical member 40 faces the opposing surface 52 of the barrel 50, and a space is formed between the groove 42 of the groove forming surface 48 of the flat helical member 40 and the opposing surface 52 of the barrel 50. The shaping section 110 supplies the raw material MR from the material supply section 20 to the material inlet 44 into the space between the flat helical member 40 and the barrel 50.

[0042] A heater 58, serving as a heating element, is embedded in the barrel 50. The heater 58 heats the raw material MR supplied to the groove 42 of the rotating flat helix 40. However, the heating element may also be located outside the barrel 50. Furthermore, a plurality of guide grooves 54 are formed on the opposing surface 52. These guide grooves 54 are connected to the connecting hole 56 and extend outwards in a vortex-like manner from the connecting hole 56. However, a structure without guide grooves 54 may also be used. The raw material MR supplied to the groove 42 of the flat helix 40 is melted within the groove 42 and flows along the groove 42 due to the rotation of the flat helix 40, being guided as a molding material towards the central portion 46 of the flat helix 40. The flowing, paste-like molding material that enters the central portion 46 is then guided by a heating element provided with… Figure 3The material is supplied to the ejector section 60 through the connecting hole 56 at the center of the barrel 50 shown. Furthermore, in the molding material, it is not necessary to melt all the types of substances constituting the molding material. The molding material only needs to be transformed into a fluid state by melting at least a portion of the substances constituting the molding material.

[0043] The ejection section 60 has a nozzle 61 for ejecting molding material, a molding material flow channel 65 disposed between the flat spiral member 40 and the nozzle 61, and an opening and closing mechanism 70 for opening and closing the flow channel 65. The nozzle 61 is connected to the communication hole 56 of the barrel 50 through the flow channel 65. The nozzle 61 ejects the molding material generated in the molding material generation section 30 from the top ejection port 62 toward the stage 210.

[0044] The opening and closing mechanism 70 opens and closes the flow channel 65, thereby controlling the outflow of molding material from the nozzle 61. In this embodiment, the opening and closing mechanism 70 is a butterfly valve. The opening and closing mechanism 70 includes a drive shaft 72 as a shaft-like member extending in one direction, a valve body 73 that rotates by the rotation of the drive shaft 72, and a valve drive unit 74 that generates the rotational driving force of the drive shaft 72.

[0045] The drive shaft 72 is installed midway through the flow channel 65, intersecting the flow direction of the molding material. More specifically, the drive shaft 72 is installed parallel to the Y-axis direction, which is perpendicular to the flow direction of the molding material within the flow channel 65. The drive shaft 72 is capable of rotating about a central axis along the Y-axis direction.

[0046] The valve body 73 is a plate-shaped component that rotates within the flow channel 65. In this embodiment, the valve body 73 is formed by machining the portion disposed within the flow channel 65 of the drive shaft 72 into a plate shape. The shape of the valve body 73 when viewed in a direction perpendicular to the plate surface is substantially the same as the opening shape of the flow channel 65 at the portion where the valve body 73 is disposed.

[0047] The valve drive unit 74 rotates the drive shaft 72 under the control of the control unit 101. The valve drive unit 74 is, for example, a stepper motor. The rotation of the drive shaft 72 causes the valve body 73 to rotate within the flow channel 65.

[0048] The flow channel 65 is closed when the plate surface of the valve body 73 is perpendicular to the flow direction of the molding material in the flow channel 65. In this state, the inflow of molding material from the flow channel 65 to the nozzle 61 is blocked, thereby stopping the outflow of molding material from the outlet 62. When the plate surface of the valve body 73 rotates from this perpendicular state due to the rotation of the drive shaft 72, the inflow of molding material from the flow channel 65 to the nozzle 61 is allowed, thereby allowing the amount of molding material ejected corresponding to the rotation angle of the valve body 73 to flow out from the outlet 62. Figure 1 As shown, the flow direction of the molding material in the flow channel 65 is such that the flow channel 65 is fully open. In this state, the amount of molding material ejected per unit time from the nozzle 62 is maximized. Thus, the opening and closing mechanism 70 can adjust the amount of molding material ejected in conjunction with the opening and closing of the molding material flow.

[0049] The stage 210 is positioned opposite the nozzle outlet 62 of the nozzle 61. In this embodiment, the surface 211 of the stage 210 opposite the nozzle outlet 62 is positioned in a horizontal direction. The three-dimensional modeling apparatus 100 shapes a three-dimensional object by spraying modeling material from the ejector 60 toward the surface 211 of the stage 210 and overlapping the layers.

[0050] The moving mechanism 230 changes the relative position of the stage 210 and the nozzle 61. In this embodiment, the position of the nozzle 61 is fixed, and the moving mechanism 230 moves the stage 210. The moving mechanism 230 is configured as a three-axis positioner that uses the driving force of three motors M to move the stage 210 in the X-axis, Y-axis, and Z-axis directions. Under the control of the control unit 101, the moving mechanism 230 changes the relative positional relationship between the nozzle 61 and the stage 210. In this specification, unless otherwise specified, the movement of the nozzle 61 refers to the relative movement of the nozzle 61 with respect to the stage 210.

[0051] Alternatively, instead of using the moving mechanism 230 to move the stage 210, a structure can be used where the stage 210 is fixed in position, and the moving mechanism 230 moves the nozzle 61 relative to the stage 210. Furthermore, a structure can be used where the moving mechanism 230 moves the stage 210 in the Z-axis direction and the nozzle 61 in the X and Y-axis directions, or a structure can be used where the moving mechanism 230 moves the stage 210 in the X and Y-axis directions and the nozzle 61 in the Z-axis direction. Even with these structures, the relative positional relationship between the nozzle 61 and the stage 210 can be changed.

[0052] The control unit 101 is a control device that controls the overall movement of the 3D modeling device 100. The control unit 101 is configured as a computer equipped with one or more processors, a main storage device, and an input / output interface for inputting and outputting signals to and from the outside. The control unit 101 performs various functions by executing programs or commands read from the main storage device through the processor. Alternatively, instead of a computer-based structure, the control unit 101 can be implemented using a structure that combines multiple circuits to implement at least some of the various functions.

[0053] Thus, the three-dimensional modeling apparatus 100 of this embodiment includes a flat helical member 40, a barrel 50, and a heater 58. The flat helical member 40 is rotatable about a rotation axis RX and has a groove forming surface 48 with a groove 42 formed at one end in the direction of the rotation axis. The barrel 50 has a counter surface 52 opposite to the groove forming surface 48 and a connecting hole 56 communicating with the counter surface 52. The heater 58 heats the material supplied to the groove 42. Hereinafter, the flat helical member 40 and the barrel 50, which are the main parts of the three-dimensional modeling apparatus 100 of this embodiment, will be described in more detail.

[0054] In the flat helical member 40 and the barrel 50 of the three-dimensional modeling apparatus 100 of this embodiment, the surface free energy of the groove forming surface 48 is lower than that of the opposing surface 52 in the region where the groove forming surface 48 and the opposing surface 52 face each other. Specifically, although the flat helical member 40 and the barrel 50 of this embodiment are both made of stainless steel (SUS), the opposing surface 52 is coated with titanium nitride (TiN), which has a higher surface free energy than SUS.

[0055] Furthermore, the surface free energy can be measured according to the experimental method for wettability of substrate glass surfaces in JIS R 3257 (1999). Table 1 shows the surface free energy calculated based on Kaelble Uy's theoretical formula, obtained by measuring the contact angles of water and n-hexadecane using a Drop Master 500 (manufactured by Kyowa Interface Chemicals Co., Ltd.) based on these measurements. In Table 1, polysilazane is NL120A (manufactured by Merck Co., Ltd.), TaOx is ALD film formed using tris(ethylformamido)(tert-butylimide) tantalum:TBTEMT, and SCA is OPTOOL DSX-E (manufactured by Daikin Industries, Ltd.). The constants for water and n-hexadecane are calculated using the values ​​in Table 2.

[0056] Table 1

[0057]

[0058] Table 2

[0059]

[0060] As shown in Table 1, since the groove forming surface 48 is SUS, the surface free energy of the groove forming surface 48 is 24.3 mJ / m. 2 Because the opposing surface 52 is coated with TiN, its surface free energy is 4.6 mJ / m higher than that of SUS. 2 28.9mJ / m 2 Furthermore, although SUS303 is used as SUS in Table 1, the same value applies to other SUS types, such as SUS440. As with the three-dimensional modeling apparatus 100 of this embodiment, it is preferable that the surface free energy of the groove forming surface 48 is lower than that of the opposing surface 52 in the region where the groove forming surface 48 faces the opposing surface 52. This is because, by providing such a structure, the material being plasticized and the plasticized material become more difficult to adhere to the flat helical member 40 in this region compared to the barrel 50, thus making it easier for the material to reach the connecting hole 56. Furthermore, by providing such a structure, it is possible to suppress the situation where the material becomes difficult to be supplied to the connecting hole 56 on the barrel 50 side, thereby enabling stable material plasticization.

[0061] Furthermore, as mentioned above, in the three-dimensional modeling device 100 of this embodiment, the difference between the surface free energy of the groove forming surface 48 and the surface free energy of the opposing surface 52 is 4.6 mJ / m. 2 Thus, the surface free energy difference in the region where the surface free energy of the groove forming surface 48 is lower than that of the opposing surface 52 is preferably 4.6 mJ / m. 2 That is because, by setting the structure in this way, it is possible to particularly effectively suppress the situation where the material is difficult to be supplied to the connecting hole 56 on the barrel 50 side, thereby enabling the material to be plasticized stably.

[0062] Furthermore, as described above, in the three-dimensional modeling apparatus 100 of this embodiment, a coating process is performed on the opposing surface 52. Preferably, the coating process is performed on at least one of the groove forming surface 48 and the opposing surface 52 in this manner, or a cutting process is performed on at least one of the groove forming surface 48 and the opposing surface 52. This is because, by setting it in this way, for example, the same material can be used to construct the groove forming surface 48 and the opposing surface 52, thereby increasing the variety of materials that can be used to manufacture the flat helical member 40 and the barrel 50. In addition, the "cutting process" here also includes texturing and surface treatment using chemicals, etc.

[0063] Furthermore, as described above, in the three-dimensional modeling apparatus 100 of this embodiment, a TiN-based titanium coating treatment is applied to the opposing surface 52. Besides titanium coating, other preferred coating treatments for the opposing surface 52 include diamond coating and chromium coating. By applying at least one of diamond coating, chromium coating, or titanium coating to the opposing surface 52, a opposing surface 52 with high surface free energy can be easily and durablely formed.

[0064] On the other hand, it is also possible to perform coating or cutting treatment on the trench forming surface 48 instead of coating or cutting treatment on the opposing surface 52. Here, a preferred coating treatment for the trench forming surface 48 is to perform a fluorine coating treatment. By performing a fluorine coating treatment on the trench forming surface 48, it is possible to easily form a trench forming surface 48 with a particularly low surface free energy.

[0065] Here, as Figure 2 As shown, the region on the outer side of the groove forming surface 48 when viewed from the Z-axis direction is designated as the first forming surface 48A, and the region on the center side when viewed from the Z-axis direction, compared to the first forming surface 48A, is designated as the second forming surface 48B. Furthermore, as... Figure 3 As shown, the region on the outside when viewed from the Z-axis direction and opposite to the first forming surface 48A is designated as the first opposing surface 52A, and the region on the center side when viewed from the Z-axis direction compared to the first opposing surface 52A and opposite to the second forming surface 48B is designated as the second opposing surface 52B.

[0066] Furthermore, in the three-dimensional modeling apparatus 100 of this embodiment, the first forming surface 48A and the second forming surface 48B of the groove forming surface 48 are both SUS without coating or cutting treatment, while the first opposing surface 52A and the second opposing surface 52B of the opposing surface 52 are both treated with a TiN-based titanium coating. That is, in the three-dimensional modeling apparatus 100 of this embodiment, the surface free energy of the first forming surface 48A is lower than that of the first opposing surface 52A, and the surface free energy of the second forming surface 48B is lower than that of the second opposing surface 52B. By setting it in this way, the material is less likely to adhere to the flat helical member 40 compared to the barrel 50 in both the entire area where the groove forming surface 48 and the opposing surface 52 are opposite, i.e., the area outside the area where the first forming surface 48A and the first opposing surface 52A are opposite, and the area on the central side where the second forming surface 48B and the second opposing surface 52B are opposite. Therefore, the material delivery force to the connecting hole 56 can be increased in the entire area where the groove forming surface 48 and the opposing surface 52 are opposite. Therefore, for example, when the nozzle 61 is set to a small diameter, the plasticized material can be injection molded from the nozzle 61 under high pressure.

[0067] However, the structure is not limited to the surface free energy relationship between the first forming surface 48A and the second forming surface 48B, and between the first opposing surface 52A and the second opposing surface 52B as described above. For example, it is possible to configure the structure so that the surface free energy of the first forming surface 48A is lower than that of the first opposing surface 52A, and the surface free energy of the second forming surface 48B is higher than that of the second opposing surface 52B. By configuring such a structure, the material is less likely to adhere to the flat helical member 40 compared to the barrel 50 in the region on the outer side opposite to the first forming surface 48A and the first opposing surface 52A. Therefore, the conveying force of the material toward the connecting hole 56 can be increased in the region on the outer side opposite to the first forming surface 48A and the first opposing surface 52A, and the material can be slowly plasticized in the region on the central side opposite to the second forming surface 48B and the second opposing surface 52B by intentionally reducing the conveying force. Therefore, for example, a large-diameter nozzle 61 can be used as the nozzle 61, and the plasticized material can be injection molded with a large injection volume.

[0068] Furthermore, for example, the surface free energy of the first forming surface 48A can be configured to be higher than that of the first opposing surface 52A, and the surface free energy of the second forming surface 48B can be lower than that of the second opposing surface 52B. By configuring it in this way, the material is less likely to adhere to the flat helical member 40 compared to the barrel 50 in the region on the central side opposite the second forming surface 48B and the second opposing surface 52B. Therefore, the material can be slowly plasticized in the region on the outer side opposite the first forming surface 48A and the first opposing surface 52A by intentionally reducing the conveying force. Furthermore, the conveying force of the material toward the connecting hole 56 can be increased in the region on the central side opposite the second forming surface 48B and the second opposing surface 52B. Therefore, for example, it is possible to slowly and sufficiently plasticize the difficult-to-plasticize material in the outer region before injection molding.

[0069] Furthermore, in the three-dimensional modeling apparatus 100 of this embodiment, a substance containing at least one of metal particles and ceramic particles can be used as the material. Although using a material containing at least one of metal particles and ceramic particles makes it particularly easy for the material to adhere to the side of the flat helical member 40, by adopting the structure described above, it is possible to suppress the material from adhering to the side of the flat helical member 40 even in this case, thereby suppressing the situation where the material is difficult to be supplied to the connecting hole 56 on the barrel 50 side. In addition to a substance containing at least one of metal particles and ceramic particles, a substance containing biodegradable composite materials such as polylactic acid and pararesin, or cellulose, or a composite thereof, can also be used as the material.

[0070] Injection molding equipment (plasticizing equipment)

[0071] Next, refer to Figure 4 The overall structure of an injection molding apparatus 310 according to an embodiment of the present invention will be described. Furthermore, the following drawings are schematic diagrams, showing some structural components omitted or simplified. The injection molding apparatus 310 of this embodiment includes a flat helical member 321 having the same groove forming surface as the flat helical member 40 of the three-dimensional modeling apparatus 100 described above, a barrel 325 having the same opposing surface as the barrel 50 of the three-dimensional modeling apparatus 100 described above, and a heater 324 serving as a heating unit. That is, the injection molding apparatus 310 of this embodiment can be considered as a plasticizing device for plasticizing materials. Furthermore, the injection molding apparatus 310 can also be considered as an apparatus that includes a plasticizing device and is capable of performing injection molding using material plasticized by the plasticizing device.

[0072] Figure 4The diagram schematically illustrates a section cutting through the injection molding apparatus 310 along the vertical direction in a cross-section encompassing the axis AX of the flow channel 450 formed in the hot runner 400. Furthermore, the axis AX corresponds to the rotational axis of the flat helix 321. Figure 4 The diagram shows mutually orthogonal U-axis, V-axis, and W-axis. The injection molding apparatus 310 injects plasticized material into a molding die to manufacture a molded article. The injection molding apparatus 310 includes a material generation unit 320, an injection unit 330, a molding die 340, a fixing unit 360 for fixing the molding die 340, a molding die opening and closing unit 350, and a control unit 390.

[0073] The material generation unit 320 plasticizes at least a portion of a solid material supplied from a hopper (not shown) positioned vertically above, thereby generating a flowable molding material, which is then supplied to the injection molding unit 330. The solid material is fed into the hopper in various granular forms, such as particles or powder. The material generation unit 320 includes a flat auger 321, a barrel 325, and a drive motor 329.

[0074] Like the flat helix 40 of the three-dimensional modeling device 100, the flat helix 321 has a generally cylindrical shape with a length along the axis AX that is less than its diameter. The flat helix 321 is configured such that the axis AX of the flow channel 450 formed in the hot runner 400 is aligned with the axis AX of the flat helix 321. A groove 322 is formed on the groove forming surface 311 of the flat helix 321, and a material inlet 23 is formed on the outer peripheral surface of the flat helix 321. The groove 322 continues to the material inlet 323. The material inlet 323 receives solid material supplied from the hopper.

[0075] The barrel 325 has a generally circular plate-like shape, and it is positioned opposite the groove forming surface 311 of the flat helical member 321 at the opposing surface 327. A heater 324, serving as a heating element for heating the material, is embedded in the barrel 325. However, the heating element may also be located outside the barrel 325. Furthermore, a through hole 326 extending along the axis AX is formed in the barrel 325. The through hole 326 functions as a flow channel guiding the molding material to the hot runner 400. An injection cylinder 332 is formed on the barrel 325, extending along an axis orthogonal to the axis AX. The injection cylinder 332 forms part of the injection section 330 and communicates with the through hole 326.

[0076] The drive motor 329 is connected to the end face of the flat helical member 321, which is opposite to the side of the barrel 325. The drive motor 329 is driven according to the command from the control unit 390, thereby rotating the flat helical member 321 about the axis AX.

[0077] At least a portion of the material supplied from the material inlet 323 is heated within the groove 322 of the flat helix 321 by a heater 324 disposed on the barrel 325, and is conveyed while being plasticized by the rotation of the flat helix 321, thereby increasing its fluidity, and then guided toward the through hole 326. The rotation of the flat helix 321 also enables the compression and degassing of the forming material.

[0078] The injection molding unit 330 measures the molding material supplied from the material generation unit 320 and injects it into the cavity 349 of the movable mold 348 formed in the molding die 340. The injection molding unit 330 includes an injection cylinder 332, an injection plunger 334, a one-way valve 336, an injection motor 338, and a hot runner 400.

[0079] The injection cylinder 332 is formed into a generally cylindrical shape inside the barrel 325 and communicates with the through hole 326. The injection plunger 334 is configured to slide within the injection cylinder 332. By sliding the injection plunger 334, the molding material in the through hole 326 is introduced into the injection cylinder 332 and metered. Furthermore, the molding material in the injection cylinder 332 is pressed towards the hot runner 400 side and injected into the cavity 349. A one-way valve 336 is disposed within the through hole 326 on the side of the flat helix 321, relative to the communication portion between the injection cylinder 332 and the through hole 326. The one-way valve 336 allows the flow of molding material from the flat helix 321 side to the hot runner 400 side and suppresses the backflow of molding material from the hot runner 400 side to the flat helix 321 side. The injection motor 38 is driven according to instructions from the control unit 390, causing the injection plunger 334 to slide within the injection cylinder 332. The sliding speed and amount of the injection plunger 334 are preset according to the type of molding material and the size of the cavity 349. The hot runner 400 has the function of guiding the molding material into the cavity 349 while it is heated.

[0080] The molding die 340 has a fixed die 341 and a movable die 348. Inside the fixed die 341, a hot runner mounting hole 342 is formed, extending along the axis AX. A hot runner 400 is disposed in the hot runner mounting hole 342.

[0081] The hot runner mounting hole 342 is formed such that its inner diameter gradually decreases from the material generation section 320 side. The end of the hot runner mounting hole 342 opposite to the material generation section 320 side functions as a gate opening 345 for the molding material to flow in. The gate opening 345 is configured as a generally circular hole.

[0082] The movable mold 348 is configured to face the fixed mold 341. The movable mold 348 abuts against the fixed mold 341 during mold closing and mold assembly, including during injection of the molding material and cooling, and separates from the fixed mold 341 during mold opening, including during demolding of the molded article. By abutting the fixed mold 341 and the movable mold 348, a cavity 349 communicating with the gate opening 345 is formed between the fixed mold 341 and the movable mold 348. The cavity 349 is pre-designed to the shape of the molded article to be formed by injection molding. Although in this embodiment the cavity 349 is formed directly connected to the gate opening 345, it could also be formed by further connecting it via a runner.

[0083] In this embodiment, the molding die 340 is formed of Invar steel. Invar steel has the property of having a very low coefficient of thermal expansion. Furthermore, a refrigerant runner (not shown) is formed in the molding die 340. By circulating a refrigerant such as cooling water through the refrigerant runner, the temperature of the molding die 340 is maintained at a level lower than the melting temperature of the resin, thereby cooling and hardening the molding material injected into the cavity 349. The refrigerant flows during mold closing and mold opening. Alternatively, the cooling and hardening of the molding material can be achieved using any cooling mechanism such as a Peltier element, instead of circulating a refrigerant through the refrigerant runner.

[0084] The molding die opening and closing unit 350 performs the opening and closing of the fixed die 341 and the movable die 348. The molding die opening and closing unit 350 includes a die opening and closing motor 358 and an extrusion pin 359. The die opening and closing motor 358 is driven according to instructions from the control unit 390, causing the movable die 348 to move along the axis AX. This realizes the closing, mold closing, and mold opening of the molding die 340. The extrusion pin 359 is positioned in communication with the cavity 349. The extrusion pin 359 extrudes the molded article during mold opening, thereby demolding the molded article.

[0085] The control unit 390 controls the overall operation of the injection molding apparatus 310, thereby performing injection molding. The control unit 390 is a computer equipped with a CPU, a storage device, and an input / output interface. The CPU executes a control program pre-stored in the storage device. The control unit 390 controls the temperature of the heater 130 embedded in the hot runner 400, thereby regulating the temperature of the hot runner 400. The user of the injection molding apparatus 310 can implement various settings related to the injection molding conditions by operating the controller, which serves as the input / output interface of the control unit 390.

[0086] The hot runner 400 guides the molding material supplied from the injection section 330 to the gate opening 345 while it is heated. The hot runner 400 is disposed in the hot runner mounting hole 342 of the fixed mold 341. Alternatively, the injection molding apparatus 310 may replace the hot runner 400 by having a nozzle that forms a flow channel to guide the molding material to the gate opening 345.

[0087] As described above, the injection molding apparatus 310 of this embodiment includes a flat spiral member 321 having a groove forming surface similar to that of the flat spiral member 40 of the three-dimensional modeling apparatus 100, a barrel 325 having an opposing surface similar to that of the barrel 50 of the three-dimensional modeling apparatus 100, and a heater 324 serving as a heating unit. Therefore, the injection molding apparatus 310 of this embodiment has the same features as those of the plasticizing apparatus described in the three-dimensional modeling apparatus 100. Furthermore, although the injection molding apparatus 310 of this embodiment is provided with the above-described integral structure, it is not limited to such a structure; it is sufficient that it has the above-described features as a plasticizing apparatus.

[0088] This invention is not limited to the embodiments described above, and can be implemented in various structures without departing from its spirit. For example, in order to solve some or all of the above-described problems, or to achieve some or all of the above-described effects, the technical features in the embodiments corresponding to the technical features in the various embodiments described in the summary section can be appropriately replaced or combined. Furthermore, as long as the technical feature is not described as an essential technical feature in this specification, it can be appropriately deleted.

[0089] Symbol Explanation

[0090] 20…Material supply section; 22…Connecting channel; 30…Material generation section; 31…Spiral housing; 32…Motor; 40…Flat spiral; 42…Groove; 43…Protrusion; 44…Material inlet; 46…Central section; 47…Upper surface; 48…Groove forming surface; 50…Barrel; 52…Opposing surface; 54…Guide groove; 56…Connecting hole; 58…Heater (heating section); 60…Ejection section; 61…Nozzle; 62…Ejection outlet; 65…Flow channel; 70…Opening and closing mechanism; 72…Drive shaft; 73…Valve body; 74…Valve drive section; 100…3D modeling device (plasticizing device); 101…Control section; 110…Modeling section; 210…Stage; 211…Surface; 230…Moving mechanism; 310…Injection molding device; 311…Groove forming surface; 320…Material generation section; 321…Flat spiral component; 322…Groove; 23…Material inlet; 324…Heater (heating section); 325…Barrel; 326…Through hole; 327…Opposing surface; 329…Drive motor; 330…Injection section; 332…Injection cylinder; 334…Injection plunger; 336…One-way valve; 338…Injection motor; 340…Mold; 341…Fixed mold; 342…Hot runner mounting hole; 345…Gate opening; 348…Modible mold; 349…Cavity; 350…Mold opening and closing section; 358…Mold opening and closing motor; 359…Extrusion pin; 360…Fixed section; 390…Control section; 400…Hot runner; 450…Runner; AX…Axis (rotation axis); M…Motor; MR…Raw material; RX…Rotation axis.

Claims

1. A plasticizing device, characterized in that, have: A flat helical member capable of rotating about a rotation axis and having a grooved surface with grooves formed therein, wherein the length of the flat helical member along the direction of the rotation axis is shorter than the length in the direction perpendicular to the direction along the rotation axis. A barrel having a facing surface that is opposite to the groove, and a connecting hole that communicates with the facing surface; The heating section heats the material supplied into the trench. The groove forming surface includes a region having a lower surface free energy compared to the opposing surface. The groove forming surface has a first forming surface and a second forming surface located on the center side compared to the first forming surface. The opposing surfaces have a first opposing surface that faces the first forming surface, and a second opposing surface that faces the second forming surface and is located on the central side compared to the first opposing surface. The surface free energy of the first forming surface is lower than that of the first opposing surface, and the surface free energy of the second forming surface is higher than that of the second opposing surface.

2. A plasticizing device, characterized in that, have: A flat helical member capable of rotating about a rotation axis and having a grooved surface with grooves formed therein, wherein the length of the flat helical member along the direction of the rotation axis is shorter than the length in the direction perpendicular to the direction along the rotation axis. A barrel having a facing surface that is opposite to the groove, and a connecting hole that communicates with the facing surface; The heating section heats the material supplied into the trench. The groove forming surface includes a region having a lower surface free energy compared to the opposing surface. The groove forming surface has a first forming surface and a second forming surface, wherein the second forming surface is located on the center side compared to the first forming surface. The opposing surfaces have a first opposing surface and a second opposing surface, the first opposing surface being opposite to the first forming surface, and the second opposing surface being opposite to the second forming surface and located on the center side compared to the first opposing surface. The surface free energy of the first forming surface is higher than that of the first opposing surface, and the surface free energy of the second forming surface is lower than that of the second opposing surface.

3. The plasticizing apparatus as described in claim 1 or 2, characterized in that, A coating or cutting process has been applied to at least one of the groove forming surface and the opposing surface.

4. The plasticizing device as described in claim 3, characterized in that, As part of the coating process, the opposing surfaces are treated with at least one of diamond coating, chromium coating, or titanium coating.

5. The plasticizing apparatus as described in claim 3, characterized in that, As part of the coating process, the trench forming surface is treated with a fluorine coating.

6. The plasticizing apparatus as described in claim 1, characterized in that, The material comprises at least one of metal particles and ceramic particles.

7. The plasticizing apparatus as described in claim 1, characterized in that, The difference in surface free energy between the region where the surface free energy of the groove forming surface is lower than that of the opposing surface is 4.6 mJ / m. 2 above.

8. A three-dimensional modeling device, characterized in that, have: A nozzle that ejects the material plasticized using the plasticizing apparatus according to any one of claims 1 to 7; A worktable that supports the material ejected from the nozzle.

9. An injection molding apparatus, characterized in that, have: A nozzle that ejects the material plasticized using the plasticizing apparatus according to any one of claims 1 to 7; A fixing part that fixes the molding die that receives the material ejected from the nozzle.

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