Three-dimensional modeling device

Abstract

To provide a three-dimensional molding device which can reduce such a possibility that the shape of a first molding layer collapses when a second molding layer is formed.SOLUTION: A three-dimensional molding device includes a stage, a heater, a head, a moving mechanism, and a control part, wherein the control part performs first molding layer formation processing of controlling the head and the moving mechanism, allowing the head to discharge a molding material, and forming a first molding layer, discharge stop processing of controlling the head, and stopping discharge of the molding material from the head, determination processing of determining whether or not a predetermined time has elapsed after the discharge stop processing is performed, and second molding layer formation processing of controlling the head and the moving mechanism, when it is determined in the determination processing that the predetermined time has elapsed, allowing the head to discharge a molding material, and forming a second molding layer on the first molding layer, and the control part sets the predetermined time on the basis of information on the molding time of the first molding layer.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to a three-dimensional modeling apparatus. [Background technology]

[0002] 2. Description of the Related Art Three-dimensional (3D) printing apparatuses are known that eject molten material from a nozzle, deposit it, and harden it to form a three-dimensional (3D) object. The three-dimensional (3D) object is formed as a laminated body made up of multiple printing layers.

[0003] For example, Patent Document 1 describes a three-dimensional modeling device that expels a molten material from a nozzle and cools the molten material with a cooling unit to promote hardening of the molten material expelled from the nozzle. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2019-34457 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the 3D modeling device described in Patent Document 1, the cooling unit is located near the nozzle, so only the modeling layer near the nozzle is cooled. Therefore, if the layer currently being modeled is layer n and the layer modeled immediately before layer n is layer n-1, depending on the size of layer n-1, it may be difficult to sufficiently lower the temperature of the entire layer n-1. If molten material is ejected onto layer n-1 before the entire layer n-1 is hardened, the shape of layer n-1 will be distorted. [Means for solving the problem]

[0006] One aspect of the three-dimensional printing apparatus according to the present invention is to The stage and a heater that covers the modeling area of ​​the stage and faces the stage; a head that ejects a modeling material toward the modeling region; a movement mechanism that moves the stage and the head relatively; a control unit that controls the head and the movement mechanism; Including, The control unit a first modeling layer forming process of controlling the head and the movement mechanism to eject a modeling material from the head to form a first modeling layer; a discharge stop process of controlling the head to stop the discharge of the modeling material from the head; a determination process for determining whether a predetermined time has elapsed since the discharge stop process was performed; a second modeling layer forming process that controls the head and the movement mechanism to eject a modeling material from the head and form a second modeling layer on the first modeling layer when it is determined in the determination process that the predetermined time has elapsed; and The control unit sets the predetermined time based on information related to the modeling time of the first modeling layer. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a side view schematically showing a three-dimensional modeling apparatus according to an embodiment of the present invention. [Figure 2] FIG. 1 is a cross-sectional view schematically showing a three-dimensional modeling apparatus according to an embodiment of the present invention. [Figure 3] FIG. 2 is a perspective view schematically showing a flat screw of the three-dimensional modeling apparatus according to the embodiment. [Figure 4] FIG. 2 is a plan view schematically showing a barrel of the three-dimensional modeling apparatus according to the embodiment. [Figure 5] 6 is a flowchart for explaining processing by a control unit of the three-dimensional modeling apparatus according to the present embodiment. [Figure 6] 3A and 3B are cross-sectional views for explaining a three-dimensional object forming process of the three-dimensional printing apparatus according to the embodiment. [Figure 7] 6 is a flowchart for explaining processing by a control unit of the three-dimensional modeling apparatus according to the present embodiment. [Figure 8]10 is a flowchart for explaining processing by a control unit of a three-dimensional modeling apparatus according to a first modified example of the present embodiment. [Figure 9] FIG. 10 is a cross-sectional view schematically showing a three-dimensional modeling apparatus according to a second modified example of the embodiment. [Figure 10] 10 is a flowchart for explaining processing by a control unit of a three-dimensional modeling apparatus according to a second modified example of the present embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] Preferred embodiments of the present invention will be described in detail below with reference to the drawings. Note that the embodiments described below do not unduly limit the content of the present invention as defined in the claims. Furthermore, not all of the configurations described below are necessarily essential components of the present invention.

[0009] 1. Three-dimensional printing equipment 1.1. Overall structure First, a three-dimensional printing apparatus according to this embodiment will be described with reference to the drawings. FIG. 1 is a perspective view schematically showing a three-dimensional printing apparatus 100 according to this embodiment. FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1, schematically showing the three-dimensional printing apparatus 100 according to this embodiment. Note that in FIGS. 1 and 2, an X-axis, a Y-axis, and a Z-axis are shown as three mutually orthogonal axes. The X-axis and Y-axis directions are, for example, horizontal directions. The Z-axis direction is, for example, vertical directions.

[0010] As shown in FIGS. 1 and 2, the three-dimensional modeling apparatus 100 includes, for example, a head 10, a stage 20, a moving mechanism 30, a support member 40, a heating mechanism 50, and a control unit 60.

[0011] The three-dimensional modeling device 100 drives the movement mechanism 30 to change the relative positions of the head 10 and the stage 20 while discharging the plasticized modeling material from the head 10 toward the stage 20. In this way, the three-dimensional modeling device 100 models a three-dimensional object of a desired shape on the stage 20.

[0012] 2, the head 10 includes, for example, a material supply unit 110, a plasticizing unit 120, and a nozzle 160. The head 10 ejects the modeling material toward the modeling region 22 of the stage 20.

[0013] Pellets or powdered materials are fed into the material supply unit 110. The material supply unit 110 supplies raw materials to the plasticization unit 120. The material supply unit 110 is configured by, for example, a hopper. The material supplied by the material supply unit 110 is, for example, acrylonitrile butadiene styrene (ABS) resin.

[0014] The material supply unit 110 and the plasticizing unit 120 are connected by a supply path 112 provided below the material supply unit 110. The material fed into the material supply unit 110 is supplied to the plasticizing unit 120 via the supply path 112.

[0015] 2, the plasticizing unit 120 includes, for example, a screw case 122, a drive motor 124, a flat screw 130, a barrel 140, and a heater 150. The plasticizing unit 120 plasticizes the solid material supplied from the material supply unit 110 to generate a fluid, paste-like modeling material, which is then supplied to the nozzle 160.

[0016] Plasticization is a concept that includes melting, and refers to changing from a solid to a fluid state. Specifically, for materials that undergo glass transition, plasticization refers to raising the temperature of the material above the glass transition point. For materials that do not undergo glass transition, plasticization refers to raising the temperature of the material above the melting point.

[0017] The screw case 122 is a housing that houses the flat screw 130. A barrel 140 is provided on the bottom surface of the screw case 122. The flat screw 130 is housed in the space surrounded by the screw case 122 and the barrel 140.

[0018] The drive motor 124 is provided on the upper surface of the screw case 122. The drive motor 124 is, for example, a servo motor. A shaft 126 of the drive motor 124 is connected to an upper surface 131 of the flat screw 130. The drive motor 124 is controlled by the control unit 60. Although not shown, the shaft 126 of the drive motor 124 and the upper surface 131 of the flat screw 130 may be connected via a reducer.

[0019] The flat screw 130 has a generally cylindrical shape whose size in the direction of the rotation axis R is smaller than its size in the direction perpendicular to the direction of the rotation axis R. In the illustrated example, the rotation axis R is parallel to the Z axis. The torque generated by the drive motor 124 causes the flat screw 130 to rotate about the rotation axis R.

[0020] The flat screw 130 has an upper surface 131, a groove-forming surface 132 opposite the upper surface 131, and a side surface 133 connecting the upper surface 131 and the groove-forming surface 132. A first groove 134 is formed in the groove-forming surface 132. The side surface 133 is, for example, perpendicular to the groove-forming surface 132. Here, FIG. 3 is a perspective view schematically showing the flat screw 130. For convenience, FIG. 3 shows a state in which the up-down positional relationship is reversed from the state shown in FIG. 2.

[0021] As shown in FIG. 3 , a first groove 134 is formed in the groove forming surface 132 of the flat screw 130. The first groove 134 has, for example, a central portion 135, a connecting portion 136, and a material introduction portion 137. The central portion 135 faces a communication hole 146 formed in the barrel 140. The central portion 135 communicates with the communication hole 146. The connecting portion 136 connects the central portion 135 and the material introduction portion 137. In the example shown, the connecting portion 136 is provided in a spiral shape from the central portion 135 toward the outer periphery of the groove forming surface 132. The material introduction portion 137 is provided on the outer periphery of the groove forming surface 132. That is, the material introduction portion 137 is provided on the side surface 133 of the flat screw 130. The material supplied from the material supply unit 110 is introduced into the first groove 134 from the material introduction unit 137, and is transported through the connection unit 136 and the central unit 135 to the communication hole 146 formed in the barrel 140. For example, two first grooves 134 are provided.

[0022] The number of first grooves 134 is not particularly limited. Although not shown, three or more first grooves 134 may be provided, or only one first groove 134 may be provided. Furthermore, although not shown, the three-dimensional modeling apparatus 100 may have an in-line screw instead of the flat screw 130.

[0023] As shown in Fig. 2, the barrel 140 is provided below the flat screw 130. The barrel 140 has an opposing surface 142 that faces the groove forming surface 132 of the flat screw 130. A communication hole 146 that communicates with the first groove 134 is formed in the center of the opposing surface 142. Here, Fig. 4 is a plan view that schematically shows the barrel 140.

[0024] As shown in FIG. 4 , second grooves 144 and communication holes 146 are formed in the opposing surface 142 of the barrel 140. A plurality of second grooves 144 are formed. In the illustrated example, six second grooves 144 are formed, but the number of second grooves 144 is not particularly limited. The plurality of second grooves 144 are formed around the communication holes 146 when viewed from the Z-axis direction. One end of each second groove 144 is connected to the communication holes 146, and the second grooves 144 extend in a spiral shape from the communication holes 146 toward the outer periphery 148 of the barrel 140. The second grooves 144 have the function of guiding the plasticized material to the communication holes 146.

[0025] The shape of second groove 144 is not particularly limited, and may be linear, for example. One end of second groove 144 does not have to be connected to communicating hole 146. Furthermore, second groove 144 does not have to be formed on opposing surface 142. However, in consideration of efficiently guiding the plasticized material to communicating hole 146, second groove 144 is preferably formed on opposing surface 142.

[0026] As shown in FIG. 2, the heater 150 is provided in the barrel 140. The heater 150 heats the material supplied between the flat screw 130 and the barrel 140. The output of the heater 150 is controlled by the control unit 60. The plasticizing unit 120 heats the material while transporting it toward the communicating holes 146 using the flat screw 130, the barrel 140, and the heater 150, generating a plasticized modeling material, and causes the generated modeling material to flow out of the communicating holes 146. Although not shown, the heater 150 may have a ring-like shape when viewed from the Z-axis direction.

[0027] The nozzle 160 is provided below the barrel 140. The nozzle 160 discharges the material supplied from the plasticizing section 120 toward the stage 20. A nozzle flow path 162 is formed in the nozzle 160. The nozzle flow path 162 communicates with the communication hole 146. The nozzle flow path 162 has a nozzle opening 164. The nozzle opening 164 is located at the tip of the nozzle 160. The material supplied from the communication hole 146 passes through the nozzle flow path 162 and is discharged from the nozzle opening 164.

[0028] As shown in FIGS. 1 and 2, the stage 20 is provided below the nozzle 160. In the illustrated example, the stage 20 has a rectangular parallelepiped shape. The stage 20 has a printing region 22. A printing material is ejected from the head 10 into the printing region 22. The printing region 22 is an area on the upper surface of the stage 20. The printing region 22 is determined by the position of the nozzle opening 164 of the head 10. For example, when the stage 20 is moved in the X-axis direction and the Y-axis direction by the movement mechanism 30, the end of the printing region 22 in the -X-axis direction is located below the nozzle opening 164 when the stage 20 has moved the furthest in the +X-axis direction. The end of the printing region 22 in the +X-axis direction is located below the nozzle opening 164 when the stage 20 has moved the furthest in the -X-axis direction.

[0029] The movement mechanism 30 supports the stage 20. The movement mechanism 30 moves the stage 20 and the head 10 relative to each other. Furthermore, the movement mechanism 30 moves the stage 20 and the heating mechanism 50 relative to each other. The heating mechanism 50 moves, for example, in conjunction with the movement of the head 10. In the illustrated example, the movement mechanism 30 moves the stage 20 in the X-axis direction and the Y-axis direction, thereby changing the relative positions of the stage 20, the head 10, and the heating mechanism 50 in the X-axis direction and the Y-axis direction. Furthermore, the movement mechanism 30 moves the head 10 and the heating mechanism 50 in the Z-axis direction, thereby changing the relative positions of the stage 20, the head 10, and the heating mechanism 50 in the Z-axis direction.

[0030] The movement mechanism 30 has, for example, a first electric actuator 32, a second electric actuator 34, and a third electric actuator 36. The first electric actuator 32 moves the stage 20 in the X-axis direction. The second electric actuator 34 moves the stage 20 in the Y-axis direction. The third electric actuator 36 moves the head 10 and the heating mechanism 50 in the Z-axis direction.

[0031] The support member 40 is connected to a third electric actuator 36. In the illustrated example, the support member 40 extends from the third electric actuator 36 in the -Y-axis direction. The support member 40 supports the head 10 and the heating mechanism 50. The movement mechanism 30 moves the support member 40 in the Z-axis direction using the third electric actuator 36, thereby moving the head 10 and the heating mechanism 50 in the Z-axis direction.

[0032] The heating mechanism 50 is, for example, substantially plate-shaped. The heating mechanism 50 includes, for example, a support plate 52 and a heater 54. The heater 54 is supported by the support plate 52. The heater 54 covers the modeling region 22 of the stage 20. The heater 54 faces the stage 20. When viewed from the Z-axis direction, the stage 20 is, for example, provided inside the outer edge of the heater 54. The heater 54 heats a modeling layer made of a modeling material deposited in the modeling region 22. The heater 54 is capable of heating the entire modeling region 22. The output of the heater 54 is controlled by the control unit 60.

[0033] 2, a through-hole 56 is formed in the heating mechanism 50. In the illustrated example, the through-hole 56 penetrates the heating mechanism 50 in the Z-axis direction. A nozzle 160 is located in the through-hole 56. In the illustrated example, the flat screw 130 and the barrel 140 are located in the +Z-axis direction of the heating mechanism 50, and the nozzle opening 164 and the stage 20 are located in the −Z-axis direction of the heating mechanism 50.

[0034] The shape of the heating mechanism 50 is not particularly limited as long as the heater 54 can heat the modeling region 22. For example, the three-dimensional modeling apparatus 100 may have a chamber (not shown) that houses the head 10, the stage 20, and the movement mechanism 30, and the heating mechanism 50 may heat the entire chamber, thereby heating the modeling region 22.

[0035] The control unit 60 is configured, for example, by a computer having a processor, a main memory device, and an input / output interface for inputting and outputting signals from and to the outside. The control unit 60 performs various functions, for example, by the processor executing a program loaded into the main memory device. Specifically, the control unit 60 controls the head 10, the movement mechanism 30, and the heating mechanism 50. Note that the control unit 60 may be configured not as a computer, but as a combination of multiple circuits.

[0036] 1.2. Control section processing FIG. 5 is a flowchart for explaining the processing of the control unit 60. For example, the user operates an operation unit (not shown) to output a processing start signal to the control unit 60 to start processing. The operation unit is composed of, for example, a mouse, keyboard, touch panel, etc. The control unit 60 starts processing when it receives the processing start signal. Each process will be explained below.

[0037] 1.2.1. Printing data acquisition process First, as shown in FIG. 5, the control unit 60 performs a modeling data acquisition process to acquire modeling data for forming a three-dimensional object (step S10).

[0038] The modeling data is created, for example, by loading shape data into slicer software installed on a computer connected to the three-dimensional modeling apparatus 100. The shape data is data representing the target shape of a three-dimensional object created using three-dimensional CAD (Computer Aided Design) software, three-dimensional CG (Computer Graphics) software, or the like. As the shape data, for example, data in STL (Standard Triangulated Language) format or AMF (Additive Manufacturing File Format) is used. The slicer software divides the target shape of the three-dimensional object into layers of a predetermined thickness and creates modeling data for each layer. The modeling data is expressed in G-code or the like.

[0039] The modeling data includes, for example, information regarding the movement path of the nozzle 160 relative to the stage 20, the amount of modeling material dispensed from the nozzle 160, the area of ​​each of the multiple modeling layers that make up the three-dimensional model, and cleaning of the nozzle 160. The "area of ​​a modeling layer" refers to the area of ​​the modeling layer as viewed from the Z-axis direction, which is the direction in which the modeling material is dispensed. The control unit 60 acquires the modeling data from a computer connected to the three-dimensional modeling apparatus 100 or a recording medium such as a USB (Universal Serial Bus) memory.

[0040] 1.2.2. Three-dimensional object formation processing Next, the control unit 60 performs a three-dimensional object formation process to form a three-dimensional object on the stage 20 (step S20).

[0041] Specifically, the control unit 60 plasticizes the material supplied between the flat screw 130 and the barrel 140 to generate the modeling material, and then discharges the modeling material from the nozzle 160. The control unit 60 continues to generate the modeling material, for example, until the three-dimensional object formation process is completed. Furthermore, the control unit 60 drives the heater 54. The control unit 60 continues to drive the heater 54, for example, until the three-dimensional object formation process is completed. Here, FIG. 6 is a cross-sectional view for explaining the three-dimensional object formation process.

[0042] As shown in Figure 6, based on the acquired modeling data, the control unit 60 controls the moving mechanism 30 to change the relative position between the nozzle 160 and the stage 20, while controlling the head 10 to eject modeling material from the nozzle 160 toward the stage 20.

[0043] Specifically, before the three-dimensional object formation process starts, i.e., before formation of the first formation layer L1 starts, the nozzle 160 is positioned at an initial position in the -X axis direction, further away from the end of the stage 20 in the -X axis direction. When the three-dimensional object formation process starts, as shown in FIG. 6, the control unit 60 controls the movement mechanism 30 to, for example, move the nozzle 160 relative to the stage 20 in the +X axis direction. As the nozzle 160 passes over the stage 20, a formation material is ejected from the nozzle 160. This forms the formation layer L1. In FIG. 6, n is an arbitrary natural number, and up to the n-th formation layer Ln are illustrated.

[0044] FIG. 7 is a flowchart for explaining the three-dimensional object formation process by the control unit 60 in more detail.

[0045] When the above-mentioned modeling data acquisition process is completed, the control unit 60 performs a waiting time setting process to set a waiting time based on information regarding the modeling time of the n-1th modeling layer Ln-1, as shown in Figure 7 (step S21).

[0046] Here, the "standby time" refers to the time during which the head 10 waits in a state where the ejection of the modeling material from the head 10 is stopped after the modeling layer Ln-1 is formed in step S25, which will be described later. The shorter the modeling time for the modeling layer Ln-1, the sooner the nth modeling layer Ln is formed after the modeling layer Ln-1 is formed, and therefore the nth modeling layer Ln may be formed before the modeling layer Ln-1 is hardened. Therefore, the shorter the modeling time for the modeling layer Ln-1, the longer the standby time the control unit 60 sets.

[0047] The information regarding the modeling time of the modeling layer Ln-1 is included in the modeling data. The control unit 60 may calculate and set the waiting time from information regarding the area of ​​the modeling layer Ln-1 included in the modeling data, or, if the modeling data directly includes the waiting time, may obtain the waiting time from the modeling data and set it.

[0048] Next, the control unit 60 controls the head 10 and the moving mechanism 30 based on the modeling data to perform a modeling layer formation process in which the modeling material is ejected from the head 10 to form the modeling layer Ln-1 on the stage 20 (step S22).

[0049] Next, the control unit 60 controls the head 10 to perform a discharge stop process to stop the discharge of the modeling material from the head 10 (step S23). Specifically, the control unit 60 controls a butterfly valve (not shown) provided in the head 10 to stop the discharge of the modeling material from the head 10.

[0050] Next, the control unit 60 performs a determination process based on the modeling data to determine whether or not the formation of all modeling layers has been completed (step S24).

[0051] If it is determined that the formation of all the modeling layers has not been completed ("NO" in step S24), the control unit 60 performs a determination process to determine whether a predetermined time has elapsed since the discharge stop process was performed (step S25). The "predetermined time" refers to the waiting time set in step S21 described above.

[0052] If it is determined that the waiting time has not elapsed since the discharge stop process was performed ("NO" in step S25), the control unit 60 repeats step S25 until it determines that the waiting time has elapsed since the discharge stop process was performed. On the other hand, if it is determined that the waiting time has elapsed since the discharge stop process was performed ("YES" in step S25), the control unit 60 returns the process to step S21.

[0053] If it is determined that the formation of all the modeling layers has been completed ("YES" in step S24), the control unit 60 ends the process.

[0054] 1.3. Effects In the three-dimensional modeling apparatus 100, the control unit 60 performs the following operations: a first modeling layer formation process in which the head 10 and the movement mechanism 30 are controlled to eject the modeling material from the head 10 to form a modeling layer Ln-1 as a first modeling layer; a discharge stop process in which the head 10 is controlled to stop the ejection of the modeling material from the head 10; a determination process in which the control unit 60 determines whether a standby time has elapsed since the discharge stop process; and a second modeling layer formation process in which the control unit 60 controls the head 10 and the movement mechanism 30 to eject the modeling material from the head 10 to form a modeling layer Ln as a second modeling layer on the modeling layer Ln-1 if the determination process determines that the standby time has elapsed. The control unit 60 sets the standby time based on information related to the modeling time of the modeling layer Ln-1.

[0055] Therefore, in the three-dimensional printing apparatus 100, the temperature of the entire modeling layer Ln-1 can be lowered before the modeling layer Ln is formed. This allows the entire modeling layer Ln-1 to harden. This reduces the possibility that the shape of the modeling layer Ln-1 will be distorted when the modeling layer Ln is formed.

[0056] Furthermore, the three-dimensional modeling apparatus 100 can cool the modeling layer Ln-1 more uniformly than when the modeling layer Ln-1 is locally cooled by a cooling unit such as a blower. When the modeling layer Ln-1 is locally cooled by a cooling unit, the stress caused by thermal contraction of the modeling layer Ln-1 becomes uneven. The three-dimensional modeling apparatus 100 cools the modeling layer Ln-1 without using a cooling unit such as a blower, so the modeling layer Ln-1 can be cooled gradually, thereby increasing the uniformity of the stress generated in the modeling layer Ln-1.

[0057] 2. Variations 2.1. First variant Next, a three-dimensional printing apparatus according to a first modified example of this embodiment will be described with reference to the drawings. Fig. 8 is a flowchart illustrating a three-dimensional object formation process performed by the control unit 60 of the three-dimensional printing apparatus according to the first modified example of this embodiment.

[0058] Hereinafter, in the 3D printing device according to the first modified example of this embodiment, differences from the example of the 3D printing device 100 according to this embodiment described above will be described, and a description of similarities will be omitted. This also applies to the 3D printing devices according to the second and third modified examples of this embodiment described later.

[0059] As shown in FIG. 8, the three-dimensional printing apparatus according to the first modified example of this embodiment differs from the above-described three-dimensional printing apparatus 100 in that it performs a first movement process (step S35) and a second movement process (step S37).

[0060] As shown in FIG. 8 , the control unit 60 performs a waiting time setting process (step S31), a modeling layer forming process (step S32), a discharge stopping process (step S33), and a determination process (step S34). Then, the control unit 60 controls the movement mechanism 30 to move the stage 20 and the heater 54 relative to each other, thereby performing a first movement process (step S35) to increase the distance between the stage 20 and the heater 54. Specifically, the control unit 60 controls the movement mechanism 30 to move the head 10 and the heating mechanism 50 in the +Z axis direction, thereby moving the head 10 and the heating mechanism 50 away from the stage 20. As a result of the first movement process, the distance between the upper surface of the modeling layer formed on the stage 20 and the heater 54 becomes, for example, approximately 15 cm. The process steps S31 to S34 are the same as the process steps S21 to S24 described above.

[0061] Next, the control unit 60 performs a determination process (step S36) to determine whether or not the waiting time has elapsed since the discharge stop process was performed. The details of the process in step S36 are the same as the details of the process in step S25 described above.

[0062] If it is determined that the waiting time has elapsed since the discharge stop process was performed ("YES" in step S36), the control unit 60 controls the movement mechanism 30 to move the stage 20 and the heater 54 relative to each other, thereby performing a second movement process to reduce the distance between the stage 20 and the heater 54 (step S37). Specifically, the control unit 60 controls the movement mechanism 30 to move the head 10 and the heating mechanism 50 in the -Z axis direction, thereby bringing the head 10 and the heating mechanism 50 closer to the stage 20. As a result of the second movement process, the distance between the upper surface of the modeling layer formed on the stage 20 and the heater 54 becomes, for example, approximately 1 mm.

[0063] Next, the control unit 60 returns the process to step S31.

[0064] In the three-dimensional printing apparatus according to the first variant of this embodiment, the control unit 60 controls the moving mechanism 30 to perform a first movement process between the discharge stop process and the judgment process to increase the distance between the stage 20 and the heater 54, and controls the moving mechanism 30 to perform a second movement process between the judgment process and the second printing layer formation process to decrease the distance between the stage 20 and the heater 54.

[0065] In the three-dimensional printing apparatus according to the first modification of this embodiment, the first movement process increases the distance between the stage 20 and the heater 54, thereby improving the heat dissipation of the modeling layer Ln-1 during the standby time. If the distance between the stage and the heater is small, the heater may hinder the heat dissipation of the modeling layer Ln-1 during the standby time.

[0066] In particular, when the modeling layers are stacked on the stage 20 and the total thickness of the stacked modeling layers is 2 mm or more, the temperature of the upper surface of the stacked modeling layers is dominated by the output of the heater 54 of the heating mechanism 50 rather than the output of the heater 150 provided in the barrel 140. Therefore, it is preferable to perform the first movement process, especially when the total thickness of the modeling layers stacked on the stage 20 is 2 mm or more and 7 mm or less.

[0067] Although the output of the heater 54 can be stopped, the heater 54 has a large heat storage capacity, and the temperature of the heater 54 may not drop immediately even if the output of the heater 54 is stopped. For this reason, the first movement process described above is effective.

[0068] Furthermore, in the three-dimensional printing apparatus according to the first modified example of this embodiment, the second movement process reduces the distance between the stage 20 and the heater 54, so that when the modeling layer Ln is formed, the upper surface of the modeling layer Ln-1 can be heated by the heater 54. This increases the adhesion strength between the modeling layer Ln-1 and the modeling layer Ln.

[0069] 2.2. Second Variant Next, a three-dimensional printing apparatus according to a second modified example of this embodiment will be described with reference to the drawings. Fig. 9 is a cross-sectional view schematically showing a three-dimensional printing apparatus 200 according to the second modified example of this embodiment. Fig. 10 is a flowchart for explaining a three-dimensional object formation process performed by the control unit 60 of the three-dimensional printing apparatus 200 according to the second modified example of this embodiment.

[0070] As shown in FIG. 9, the three-dimensional modeling apparatus 200 differs from the above-described three-dimensional modeling apparatus 100 in that it includes a cleaning mechanism 70.

[0071] The cleaning mechanism 70 cleans the head 10. Specifically, the cleaning mechanism 70 cleans the nozzles 160. In this way, if the nozzle openings 164 are clogged, the nozzle openings 164 can be unclogged. The form of the cleaning mechanism 70 is not particularly limited as long as it can clean the nozzles 160.

[0072] 10, the control unit 60 performs a waiting time setting process (step S41), a modeling layer forming process (step S42), a discharge stopping process (step S43), and a determination process (step S44), and then performs a determination process to determine whether or not to clean the head 10 based on the modeling data (step S45). Note that the contents of the processes in steps S41 to S44 are the same as the contents of the processes in steps S21 to S24 described above, respectively.

[0073] If it is determined that the head 10 should be cleaned ("YES" in step S45), the control unit 60 performs a determination process to determine whether the waiting time set in step S41 is longer than the time required for cleaning the head 10 by the cleaning mechanism 70 (step S46).

[0074] If it is determined that the waiting time is longer than the cleaning time, the control unit 60 controls the cleaning mechanism 70 to perform a process to start cleaning the head 10 (step S47). By this process, the control unit 60 can make the cleaning mechanism 70 clean the head 10 until the waiting time has elapsed after the discharge stop process.

[0075] Next, the control unit 60 performs a determination process (step S48) to determine whether or not a predetermined time has elapsed since the discharge stopping process was performed. The process content of step S48 is the same as the process content of step S25 described above.

[0076] If it is determined that the head 10 is not to be cleaned ("NO" in step S45), the control unit 60 skips steps S46 and S47 and performs the process of step S48.

[0077] If it is determined that the waiting time is not longer than the cleaning time ("NO" in step S46), the control unit 60 skips the process of step S47 and performs the process of step S48.

[0078] In the three-dimensional modeling device 200, if the standby time is longer than the time required for cleaning the head 10 by the cleaning mechanism 70, the control unit 60 controls the cleaning mechanism 70 to clean the head 10 during the period from when the discharge stop process is performed until the standby time has elapsed. Therefore, in the three-dimensional modeling device 200, the time required for modeling a three-dimensional object can be shortened compared to when cleaning is not performed during the standby time but a separate cleaning time is provided.

[0079] 2.3. Third Variant Next, a three-dimensional modeling apparatus according to a third modified example of this embodiment will be described.

[0080] In the above-described three-dimensional modeling apparatus 100, the material supplied from the material supply unit 110 is ABS resin.

[0081] In contrast, in the three-dimensional modeling apparatus according to the third modified example of this embodiment, the material supplied from the material supply unit 110 is a material other than ABS resin, or a material in which other components are added to ABS resin.

[0082] Examples of materials supplied from the material supply unit 110 include materials containing various materials as main components, such as thermoplastic materials, metal materials, and ceramic materials. Here, the term "main material" refers to the material that forms the core of the shape of the object, and refers to a material that accounts for 50% by mass or more of the object. The above-mentioned materials include those obtained by melting the main material alone, and those obtained by melting some of the components contained in the main material and turning it into a paste.

[0083] Examples of the thermoplastic material that can be used include thermoplastic resins, such as general-purpose engineering plastics and super engineering plastics.

[0084] Examples of general-purpose engineering plastics include polypropylene (PP), polyethylene (PE), polyacetal (POM), polyvinyl chloride (PVC), polyamide (PA), polylactic acid (PLA), polyphenylene sulfide (PPS), polycarbonate (PC), modified polyphenylene ether, polybutylene terephthalate, and polyethylene terephthalate.

[0085] Examples of super engineering plastics include polysulfone (PSU), polyethersulfone (PES), polyphenylene sulfide (PPS), polyarylate (PAR), polyimide (PI), polyamideimide (PAI), polyetherimide (PEI), and polyetheretherketone (PEEK).

[0086] The thermoplastic material may contain pigments, metals, ceramics, and other additives such as wax, flame retardants, antioxidants, and thermal stabilizers. The thermoplastic material is plasticized and converted into a molten state in the plasticizing unit 120 by the rotation of the flat screw 130 and the heating of the heater 150. The modeling material thus produced hardens as the temperature drops after being ejected from the nozzle 160. It is desirable that the thermoplastic material be heated to or above its glass transition point and ejected from the nozzle 160 in a completely molten state.

[0087] In place of the thermoplastic material described above, for example, a metal material may be used as the main material in the plasticizing unit 120. In this case, it is desirable that a powder material made by powdering the metal material is mixed with a component that melts when generating the modeling material, and then introduced into the plasticizing unit 120.

[0088] Examples of metal materials include single metals such as magnesium (Mg), iron (Fe), cobalt (Co), chromium (Cr), aluminum (Al), titanium (Ti), copper (Cu), and nickel (Ni), or alloys containing one or more of these metals, as well as maraging steel, stainless steel, cobalt-chromium-molybdenum, titanium alloys, nickel alloys, aluminum alloys, cobalt alloys, and cobalt-chromium alloys.

[0089] Instead of the above-mentioned metal materials, ceramic materials can be used as the main material in the plasticizing portion 120. Examples of ceramic materials include oxide ceramics such as silicon dioxide, titanium dioxide, aluminum oxide, and zirconium oxide, and non-oxide ceramics such as aluminum nitride.

[0090] The powder material of the metallic material or ceramic material supplied from the material supply unit 110 may be a mixed material obtained by mixing multiple types of powder of a single metal, alloy powder, or ceramic material. The powder material of the metallic material or ceramic material may also be coated with, for example, the thermoplastic resin described above or other thermoplastic resins. In this case, the thermoplastic resin may be melted in the plasticizing unit 120 to exhibit fluidity.

[0091] A solvent, for example, may be added to the powder material of the metal material or ceramic material supplied from the material supply unit 110. Examples of the solvent include water; (poly)alkylene glycol monoalkyl ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, and propylene glycol monoethyl ether; acetate esters such as ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, and isobutyl acetate; aromatic hydrocarbons such as benzene, toluene, and xylene; ketones such as methyl ethyl ketone, acetone, methyl isobutyl ketone, ethyl-n-butyl ketone, diisopropyl ketone, and acetylacetone; alcohols such as ethanol, propanol, and butanol; tetraalkylammonium acetates; sulfoxide-based solvents such as dimethyl sulfoxide and diethyl sulfoxide; pyridine-based solvents such as pyridine, γ-picoline, and 2,6-lutidine; tetraalkylammonium acetates (e.g., tetrabutylammonium acetate); and ionic liquids such as butyl carbitol acetate.

[0092] Additionally, for example, a binder may be added to the powder material of the metal material or ceramic material supplied from the material supply unit 110. Examples of binders include acrylic resin, epoxy resin, silicone resin, cellulose-based resin, other synthetic resins, PLA, PA, PPS, PEEK, and other thermoplastic resins.

[0093] The above-described embodiment and modifications are merely examples, and the present invention is not limited to these. For example, the embodiments and modifications can be combined as appropriate.

[0094] The present invention includes configurations that are substantially the same as the configurations described in the embodiments, for example, configurations with the same functions, methods, and results, or configurations with the same purpose and effects. The present invention also includes configurations that replace non-essential parts of the configurations described in the embodiments. The present invention also includes configurations that achieve the same effects or purposes as the configurations described in the embodiments. The present invention also includes configurations that add publicly known technology to the configurations described in the embodiments.

[0095] The following can be derived from the above-described embodiment and modifications.

[0096] One aspect of the three-dimensional printing apparatus is The stage and a heater that covers the modeling area of ​​the stage and faces the stage; a head that ejects a modeling material toward the modeling region; a movement mechanism that moves the stage and the head relatively; a control unit that controls the head and the movement mechanism; Including, The control unit a first modeling layer forming process of controlling the head and the movement mechanism to eject a modeling material from the head to form a first modeling layer; a discharge stop process of controlling the head to stop the discharge of the modeling material from the head; a determination process for determining whether a predetermined time has elapsed since the discharge stop process was performed; a second modeling layer forming process that controls the head and the movement mechanism to eject a modeling material from the head and form a second modeling layer on the first modeling layer when it is determined in the determination process that the predetermined time has elapsed; and The control unit sets the predetermined time based on information related to the modeling time of the first modeling layer.

[0097] This three-dimensional modeling apparatus can reduce the possibility that the shape of the first modeling layer will be distorted when the second modeling layer is formed.

[0098] In one aspect of the three-dimensional printing apparatus, the movement mechanism moves the stage and the heater relatively; The control unit a first movement process for controlling the movement mechanism to increase the distance between the stage and the heater between the discharge stop process and the determination process; a second movement process for controlling the movement mechanism to reduce the distance between the stage and the heater between the determination process and the second modeling layer formation process; may be performed.

[0099] This three-dimensional modeling device can improve the heat dissipation of the first modeling layer during standby, while also increasing the adhesive strength between the first modeling layer and the second modeling layer.

[0100] In one aspect of the three-dimensional printing apparatus, a cleaning mechanism for cleaning the head; If the specified time is longer than the time it takes for the cleaning mechanism to clean the head, the control unit may control the cleaning mechanism to clean the head from the time the ejection stop process is performed until the specified time has elapsed.

[0101] This three-dimensional modeling apparatus can reduce the time required to create a three-dimensional object. [Explanation of symbols]

[0102] 10...head, 20...stage, 22...modeling area, 30...movement mechanism, 32...first electric actuator, 34...second electric actuator, 36...third electric actuator, 40...support member, 50...heating mechanism, 52...support plate, 54...heater, 56...through hole, 60...control unit, 70...cleaning mechanism, 100...three-dimensional modeling device, 110...material supply unit, 112...supply path, 120...plasticization unit, 122...screw Case, 124...drive motor, 126...shaft, 130...flat screw, 131...upper surface, 132...groove forming surface, 133...side surface, 134...first groove, 135...center portion, 136...connection portion, 137...material introduction portion, 140...barrel, 142...opposing surface, 144...second groove, 146...communicating hole, 148...periphery, 150...heater, 160...nozzle, 162...nozzle flow path, 164...nozzle opening, 200...three-dimensional printing device

Claims

1. The stage and a heater that covers the modeling area of ​​the stage and faces the stage; a head that ejects a modeling material toward the modeling region; The stage and the head, and the stage and the heater are moved relatively to each other. a moving mechanism; a control unit that controls the head and the movement mechanism, The control unit a first nozzle for ejecting a modeling material from the head by controlling the head and the moving mechanism; a first modeling layer forming process for forming a modeling layer; a discharge stop process of controlling the head to stop the discharge of the modeling material from the head; 、 a determination process for determining whether a predetermined time has elapsed since the discharge stop process was performed; When it is determined in the determination process that the predetermined time has elapsed, the head and the moving A mechanism is controlled to eject a modeling material from the head to form a second modeling layer on the first modeling layer. a second modeling layer forming process for forming a second modeling layer; The control unit sets the predetermined time based on information about the modeling time of the first modeling layer. and, between the discharge stop process and the determination process, controlling the movement mechanism to a first movement process for increasing the distance between the heater and the first moving process; During the layer formation process, the moving mechanism is controlled to adjust the distance between the stage and the heater. and a second movement process for reducing the size of the three-dimensional object.

2. In claim 1, a cleaning mechanism for cleaning the head; The predetermined time is longer than the time required for cleaning the head by the cleaning mechanism. In this case, the control unit a three-dimensional modeling apparatus that controls the cleaning mechanism to clean the head; 。

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