Data generation method

Abstract

To improve the strength of a three dimensional shaped article.SOLUTION: A data generation method for generating shaping data for shaping a three dimensional shaped object by stacking layers of a shaping material discharged along a discharge path includes acquiring first data including information on a first discharge path for shaping a side surface portion of the three dimensional shaped object, acquiring second data including information on a second discharge path for shaping a surface layer of the three dimensional shaped object, the surface layer being not in contact with another layer on at least one of an upper side and a lower side in a layer stacking direction, and acquiring third data including information on a third discharge path for shaping an inner layer of the three dimensional shaped object, the inner layer being located inside the side surface portion and the surface layer. And a first expanding step of expanding, to a first overlapping region which overlaps the side surface portion as viewed in the stacking direction, a first adjacent layer which is included in the surface layer and which is adjacent to the first overlapping region in a layer direction perpendicular to the stacking direction.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present disclosure relates to a data generation method. [Background technology]

[0002] Patent Document 1 discloses a technology for forming a three-dimensional object by discharging a modeling material from a discharging unit and stacking layers of the modeling material. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2023-114606 Summary of the Invention [Problem to be solved by the invention]

[0004] Depending on the shape of the three-dimensional object, a surface layer, which is the bottom or top layer, may be adjacent to an internal layer different from the surface layer in a layer direction perpendicular to the stacking direction, resulting in a boundary between the surface layer and the internal layer in the layer direction. A technology for improving the strength of three-dimensional objects having such a boundary is desired. [Means for solving the problem]

[0005] According to one aspect of the present disclosure, there is provided a data generation method for generating modeling data for forming a three-dimensional object by stacking layers of modeling material discharged from a discharge unit moving along a movement path. This data generation method includes a first acquisition step of acquiring first data including information on a first discharge path that represents the movement path for forming the side portion of the three-dimensional object; a second acquisition step of acquiring second data including information on a second discharge path that represents the movement path for forming a surface layer of the three-dimensional object that is not in contact with other layers on at least one of the upper and lower sides in the layer stacking direction, and that is different from the side portion; a third acquisition step of acquiring third data including information on a third discharge path that represents the movement path for forming an internal layer of the three-dimensional object that is located inside the side portion and the surface layer; and a first expansion step of expanding a first adjacent layer that is included in the surface layer and adjacent to the first overlapping region in a layer direction perpendicular to the stacking direction, to a first overlapping region that is included in the internal layer and that overlaps the side portion when viewed in the stacking direction. [Brief explanation of the drawings]

[0006] [Figure 1] FIG. 1 is an explanatory diagram showing a schematic configuration of a three-dimensional printing system according to a first embodiment. [Figure 2] FIG. 2 is a perspective view showing a schematic configuration of the underside of a flat screw. [Figure 3] FIG. 3 is a schematic plan view showing the top side of the barrel. [Figure 4] FIG. 2 is an explanatory diagram schematically illustrating how the three-dimensional printing apparatus prints a model. [Figure 5] FIG. 1 is an explanatory diagram showing a schematic configuration of an information processing apparatus. [Figure 6] 4 is a flowchart of a formation process according to the first embodiment. [Figure 7] FIG. 4 is a diagram illustrating an example of first modeling data. [Figure 8] Cross-sectional view of VIII-VIII in Figure 7. [Figure 9] 5A to 5C are views for explaining a first example of the first extension process in the first embodiment. [Figure 10]Cross-sectional view taken along line XX in Figure 9. [Figure 11] XI-XI cross section of Figure 9. [Figure 12] 6A to 6C are views for explaining a second example of the first extension process in the first embodiment. [Figure 13] 10 is a flowchart of a formation process according to a second embodiment. [Figure 14] 10A to 10C are views for explaining a first example of the second extension process in the second embodiment. [Figure 15] 10A to 10C are views for explaining a second example of the second extension process in the second embodiment. [Figure 16] 13A to 13C are views for explaining an example of a first extension process in the third embodiment. [Figure 17] 13A to 13C are views for explaining a first example of the first extension process in the fourth embodiment. [Figure 18] 13A to 13C are views for explaining a second example of the first extension process in the fourth embodiment. [Figure 19] 13A to 13C are views for explaining an example of a first extension process in the fifth embodiment. [Figure 20] 13 is a flowchart of a formation process according to a sixth embodiment. [Figure 21] 13A to 13C are views for explaining examples of first extension processing and second extension processing in the sixth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0007] A. First embodiment: FIG. 1 is an explanatory diagram showing a schematic configuration of a three-dimensional printing system 10 according to a first embodiment. Arrows indicating mutually orthogonal X, Y, and Z directions are shown in FIG. 1. The X and Y directions are parallel to a horizontal plane, and the Z direction is a vertically upward direction. The arrows indicating the X, Y, and Z directions are also shown in other figures as appropriate so that the illustrated directions correspond to those in FIG. 1. In the following description, when specifying the direction, positive and negative signs are used in combination to indicate the direction indicated by the arrow in each figure, with "+" indicating the direction indicated by the arrow and "-" indicating the opposite direction. Hereinafter, the +Z direction will also be referred to as "up" and the -Z direction as "down."

[0008] The three-dimensional printing system 10 includes a three-dimensional printing device 100 and an information processing device 400. The three-dimensional printing device 100 of this embodiment is a device that prints a model by a material extrusion method. The three-dimensional printing device 100 includes a control unit 300 for controlling each unit of the three-dimensional printing device 100. The control unit 300 and the information processing device 400 are connected to each other so that they can communicate with each other.

[0009] The three-dimensional modeling apparatus 100 includes a modeling unit 110 that generates and dispenses a modeling material, a modeling stage 210 that serves as a base for the model, and a movement mechanism 230 that controls the dispense position of the modeling material.

[0010] Under the control of the control unit 300, the modeling unit 110 ejects a modeling material, which is a plasticized solid material, onto the stage 210. The modeling unit 110 includes a material supply unit 20, which is a supply source of raw materials before they are converted into the modeling material, a plasticization unit 30, which converts the raw materials into the modeling material, and a discharge unit 60, which discharges the modeling material.

[0011] The material supply unit 20 supplies the raw material MR to the plasticizing unit 30. The material supply unit 20 is configured, for example, by a hopper that stores the raw material MR. The material supply unit 20 is connected to the plasticizing unit 30 via a communication passage 22. The raw material MR is fed into the material supply unit 20 in the form of powder or pellets. As the raw material MR, for example, a thermoplastic resin such as acrylonitrile-butadiene-styrene resin (ABS), polypropylene resin (PP), polyethylene resin (PE), or polyacetal resin (POM) is used.

[0012] The plasticizing unit 30 plasticizes the raw material MR supplied from the material supply unit 20 to generate a paste-like modeling material that exhibits fluidity, and then guides the material to the discharge unit 60. In this embodiment, "plasticization" is a concept that includes melting, and refers to changing a material 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.

[0013] The plasticizing section 30 includes a screw case 31, a drive motor 32, a flat screw 40, and a barrel 50. The flat screw 40 is also called a rotor or a scroll. The barrel 50 is also called a screw facing portion.

[0014] The flat screw 40 is housed in a screw case 31. An upper surface 47 of the flat screw 40 is connected to the drive motor 32, and the flat screw 40 rotates in the screw case 31 by the rotational driving force generated by the drive motor 32. The drive motor 32 is driven under the control of the control unit 300. The flat screw 40 may be driven by the drive motor 32 via a reducer.

[0015] 2 is a perspective view showing the schematic configuration of the lower surface 48 side of the flat screw 40. To facilitate understanding of the technology, the flat screw 40 shown in FIG. 2 is shown with the positional relationship between the upper surface 47 and the lower surface 48 shown in FIG. 1 reversed in the vertical direction. The flat screw 40 has a roughly cylindrical shape in which the length in the axial direction, which is the direction along its central axis, is shorter than the length in the direction perpendicular to the axial direction. The flat screw 40 is positioned so that the rotation axis RX, which is its rotation center, is parallel to the Z direction.

[0016] A spiral groove 42 is formed on a lower surface 48 of the flat screw 40, which is a surface that intersects with the rotation axis RX. The communication passage 22 of the material supply unit 20 described above communicates with the groove 42 from the side surface of the flat screw 40. In this embodiment, three grooves 42 are formed, separated by ridges 43. The number of grooves 42 is not limited to three, and may be one, or two or more. The groove 42 is not limited to a spiral shape, but may also be a spiral or involute curve shape, or may have a shape that extends in an arc from a center portion 46 to the outer periphery.

[0017] 1, the lower surface 48 of the flat screw 40 faces the upper surface 52 of the barrel 50, and a space is formed between the groove 42 of the lower surface 48 of the flat screw 40 and the upper surface 52 of the barrel 50. Raw material MR is supplied to this space between the flat screw 40 and the barrel 50 from the material supply section 20 through a material inlet 44 shown in FIG.

[0018] A barrel heater 58 is embedded in the barrel 50 to heat the raw material MR supplied into the groove 42 of the rotating flat screw 40. A communication hole 56 is provided in the center of the barrel 50.

[0019] 3 is a schematic plan view showing the top surface 52 of the barrel 50. A plurality of guide grooves 54 are formed on the top surface 52 of the barrel 50, and are connected to the communicating holes 56 and extend spirally from the communicating holes 56 toward the outer periphery. Note that one end of the guide grooves 54 does not have to be connected to the communicating holes 56. Also, the guide grooves 54 can be omitted.

[0020] The raw material MR supplied into the groove 42 of the flat screw 40 is plasticized in the groove 42, flows along the groove 42 due to the rotation of the flat screw 40, and is guided to the central portion 46 of the flat screw 40 as a modeling material. The pasty modeling material that has flowed into the central portion 46 and exhibits fluidity is supplied to the discharge portion 60 through a communication hole 56 provided in the center of the barrel 50. Note that it is not necessary for all types of substances constituting the modeling material to be plasticized. It is sufficient for the modeling material to be converted into a fluid state as a whole by plasticizing at least some of the types of substances constituting the modeling material.

[0021] The discharge unit 60 in FIG. 1 includes a nozzle 61 that discharges the modeling material, a flow path 65 for the modeling material provided between the flat screw 40 and the nozzle opening 62, and a discharge control unit 77 that controls the discharge of the modeling material.

[0022] The nozzle 61 is connected to the communication hole 56 of the barrel 50 through a flow path 65. The nozzle 61 discharges the modeling material produced in the plasticizing section 30 from a nozzle opening 62 at the tip thereof toward the stage 210.

[0023] The discharge control unit 77 includes a discharge adjustment unit 70 that opens and closes the flow path 65, and a suction unit 75 that sucks in the modeling material and temporarily stores it.

[0024] The discharge adjustment unit 70 is provided in the flow path 65 and changes the opening degree of the flow path 65 by rotating within the flow path 65. In this embodiment, the discharge adjustment unit 70 is configured by a valve. The discharge adjustment unit 70 is driven by a first drive unit 74 under the control of the control unit 300. The first drive unit 74 is configured by, for example, a stepping motor. The control unit 300 can adjust the flow rate of the modeling material flowing from the plasticizing unit 30 to the nozzle 61, i.e., the discharge amount of the modeling material discharged from the nozzle 61, by using the first drive unit 74 to control the rotation angle of the discharge adjustment unit 70. The discharge adjustment unit 70 can adjust the discharge amount of the modeling material and can also control the on / off of the outflow of the modeling material.

[0025] The suction unit 75 is connected between the discharge adjustment unit 70 and the nozzle opening 62 in the flow path 65. When the discharge of the modeling material from the nozzle 61 stops, the suction unit 75 temporarily sucks the modeling material in the flow path 65, thereby suppressing the tailing phenomenon in which the modeling material hangs like a string from the nozzle opening 62. In this embodiment, the suction unit 75 is configured with a plunger. The suction unit 75 is driven by a second drive unit 76 under the control of the control unit 300. The second drive unit 76 is configured with, for example, a stepping motor or a rack-and-pinion mechanism that converts the rotational force of the stepping motor into translational motion of the plunger.

[0026] The stage 210 is disposed at a position facing the nozzle opening 62 of the nozzle 61. In the first embodiment, the modeling surface 211 of the stage 210 facing the nozzle opening 62 of the nozzle 61 is disposed so as to be parallel to the X and Y directions, i.e., the horizontal direction. The stage 210 is provided with a stage heater 212 for preventing the modeling material discharged onto the stage 210 from cooling suddenly. The stage heater 212 is controlled by the control unit 300.

[0027] The movement mechanism 230 changes the relative position between the stage 210 and the nozzle 61 under the control of the control unit 300. In this embodiment, the position of the nozzle 61 is fixed, and the movement mechanism 230 moves the stage 210. The movement mechanism 230 is configured by a three-axis positioner that moves the stage 210 in three axial directions, that is, the X, Y, and Z directions, using the driving forces of three motors. In this specification, unless otherwise specified, movement of the nozzle 61 means moving the nozzle 61 and the discharge unit 60 relative to the stage 210.

[0028] In other embodiments, instead of a configuration in which the moving mechanism 230 moves the stage 210, a configuration in which the moving mechanism 230 moves the nozzle 61 relative to the stage 210 while the position of the stage 210 is fixed may be employed. Alternatively, a configuration in which the moving mechanism 230 moves the stage 210 in the Z direction and moves the nozzle 61 in the X and Y directions, or a configuration in which the moving mechanism 230 moves the stage 210 in the X and Y directions and moves the nozzle 61 in the Z direction may be employed. Even with these configurations, the relative positional relationship between the nozzle 61 and the stage 210 can be changed.

[0029] 1 shows only one modeling unit 110, the 3D modeling device 100 may include multiple modeling units 110. By including multiple modeling units 110, different types of modeling materials can be discharged from each modeling unit 110. Therefore, for example, the main body of the modeled object and the support structure that supports the modeled object can be modeled using different types of modeling materials.

[0030] The control unit 300 is a control device that controls the overall operation of the 3D printing apparatus 100. The control unit 300 is configured by a computer that includes one or more processors 310, a storage device 320 including a main storage device and an auxiliary storage device, and an input / output interface that inputs and outputs signals to and from the outside. The processor 310 executes a program stored in the storage device 320 to control the printing unit 110 and the movement mechanism 230 in accordance with printing data acquired from the information processing device 400, and prints a printed object on the stage 210. Note that the control unit 300 may be realized by a combination of circuits instead of being configured by a computer.

[0031] 4 is an explanatory diagram that schematically shows how the three-dimensional printing apparatus 100 prints a model. In the three-dimensional printing apparatus 100, as described above, the raw material MR in a solid state is plasticized to produce the modeling material MM. The control unit 300 discharges the modeling material MM from the nozzle 61 while changing the position of the nozzle 61 relative to the stage 210 in a direction along the modeling surface 211 of the stage 210, while maintaining the distance between the nozzle 61 and the modeling surface 211 of the stage 210. The modeling material MM discharged from the nozzle 61 is continuously deposited in the direction of movement of the nozzle 61.

[0032] The control unit 300 repeatedly moves the nozzle 61 to form layers ML. After forming one layer ML, the control unit 300 moves the position of the nozzle 61 relative to the stage 210 in the Z direction, which is the stacking direction of the layers ML. Then, a model is formed by stacking additional layers ML on the layers ML that have been formed so far. In the stacking direction, the side away from the stage 210 is also referred to as the upper side of the stacking direction, and the side approaching the stage 210 is also referred to as the lower side of the stacking direction. In this embodiment, the upper side of the stacking direction is the +Z direction side. The direction perpendicular to the stacking direction is also referred to as the layer direction. The layer direction can also be said to be the direction in which the layers ML spread.

[0033] The control unit 300 may temporarily suspend the discharge of the modeling material from the nozzle 61, for example, when the nozzle 61 moves in the Z direction after completing one layer ML or when each layer has multiple independent modeling regions. In this case, the discharge adjustment unit 70 closes the flow path 65 to stop the discharge of the modeling material MM from the nozzle opening 62, and the suction unit 75 temporarily sucks the modeling material from the nozzle 61. After changing the position of the nozzle 61, the control unit 300 opens the flow path 65 with the discharge adjustment unit 70 while discharging the modeling material from the suction unit 75, thereby restarting the deposition of the modeling material MM from the new position of the nozzle 61.

[0034] 5 is an explanatory diagram showing a schematic configuration of an information processing device 400. The information processing device 400 is configured as a computer in which a CPU 410, a memory 420, a storage device 430, a communication interface 440, and an input / output interface 450 are interconnected via a bus 460. An input device 470 such as a keyboard or a mouse, and a display unit 480 such as a liquid crystal display are connected to the input / output interface 450. The information processing device 400 is connected to the control unit 300 of the three-dimensional printing apparatus 100 via the communication interface 440.

[0035] The CPU 410 functions as a data generation unit 411 by executing a program stored in the storage device 430. The data generation unit 411 generates modeling data that the three-dimensional modeling device 100 uses to model a three-dimensional object. The modeling data includes, for each layer obtained by slicing the shape of the model into multiple layers, path information that indicates the movement path of the nozzle 61 and discharge amount information that indicates the amount of modeling material discharged along each movement path. The path information includes information about line width. The line width means the width of the modeling material discharged along the movement path. Here, the "width of the modeling material" means the width in the direction perpendicular to the stacking direction and the extension direction of the movement path.

[0036] 6 is a flowchart of a modeling process executed in the three-dimensional modeling system 10. The modeling process is a process for realizing the method for manufacturing a three-dimensional object according to the present disclosure and the data generation method according to the present disclosure. The processes of steps S10 to S30 shown in FIG. 6 are executed by the information processing device 400, and the processes of steps S40 and S50 are executed by the three-dimensional modeling device 100. The processes of steps S10 to S30 correspond to the processes for realizing the data generation method according to the present disclosure.

[0037] In step S10, the data generation unit 411 of the information processing device 400 acquires shape data representing the three-dimensional shape of the three-dimensional object from another computer, a recording medium, or the storage device 430. The shape data is data representing the shape of the three-dimensional object created using three-dimensional CAD software, three-dimensional CG software, or the like. As the shape data, for example, data in STL format, AMF format, or the like is used.

[0038] In step S20, the data generation unit 411 acquires first modeling data based on the shape data acquired in step S10. More specifically, in step S20, the data generation unit 411 uses slicer software to analyze the shape data acquired in step S10 to generate the first modeling data, and acquires the first modeling data.

[0039] FIG. 7 is a diagram illustrating an example of the first modeling data acquired in step S20. FIG. 8 is a cross-sectional view taken along line VIII-VIII in FIG. 7. In FIGS. 7 and 8, first modeling data SD1 is shown as an example of the first modeling data. The first modeling data SD1 is modeling data for modeling a three-dimensional object OB. FIG. 8 shows a layer Lm, which is one of the layers constituting the three-dimensional object OB.

[0040] As shown in FIGS. 7 and 8, the first formation data SD1 includes first data D1, second data D2, and third data D3. As shown in FIG. 8, the first data D1 includes path information for the first discharge path PD1. The first discharge path PD1 is a path for forming the side surface portion WA of the three-dimensional object OB. The second data D2 includes path information for the second discharge path PD2. The second discharge path PD2 is a path for forming the surface layer SA of the three-dimensional object OB. The surface layer SA is a region not in contact with other layers on at least one of the upper and lower sides in the stacking direction. In this embodiment, the surface layer SA includes a top layer TA and a bottom layer BA. The top layer TA is a region not in contact with other layers on the upper side in the stacking direction. The bottom layer BA is a region not in contact with other layers on the lower side in the stacking direction. The third data D3 includes path information for the third discharge path PD3. The third discharge path PD3 is a path for forming an inner layer IA of the three-dimensional object OB. The inner layer IA is an area located inside the side surface portion WA and the surface layer SA.

[0041] As shown in Fig. 7, the three-dimensional object OB has a first portion OP1 and a second portion OP2. The first portion OP1 has a rectangular parallelepiped shape that is elongated in the Z direction, and has a bottom layer BAb and a top layer TAb as surface layers SA. The bottom layer BAb forms the lower bottom surface of the first portion OP1, and the top layer TAb forms the upper bottom surface of the first portion OP1. The first portion OP1 is formed so that the bottom layer BAb directly or indirectly contacts the forming surface 211 of the stage 210 during three-dimensional forming.

[0042] The second portion OP2 is an overhanging portion. An overhanging portion refers to a protruding portion of the three-dimensional object that is not supported below. In this embodiment, the term "overhanging portion" also includes a bridge portion. A bridge portion refers to a bridge-like portion of the three-dimensional object that is supported at both ends. The second portion OP2 is located on the +X direction side of the first portion OP1. The second portion OP2 has a rectangular parallelepiped shape and includes a bottom layer BAa and a top layer TAa as surface layers SA. The bottom layer BAa forms the lower bottom surface of the second portion OP2, and the top layer TAa forms the upper bottom surface of the second portion OP2. The bottom layer BAa is located above the bottom layer BAb of the first portion OP1. The top layer TAa is located below the top layer TAb of the first portion OP1.

[0043] As shown in Figures 7 and 8, the layer Lm includes a top layer TAa. The layer Lm also includes a side layer WAm and an internal layer IAm. The side layer WAm is a layer that is located at the same height as the top layer TAa in the stacking direction among the layers that make up the side portion WA. The internal layer IAm is a layer that is located at the same height as the top layer TAa in the stacking direction among the internal layers IA.

[0044] As shown in FIG. 7, in this embodiment, the first formation data SD1 further includes fourth data D4. The fourth data D4 includes path information of the fourth discharge path. The fourth discharge path is a movement path for forming the intermediate layer MA of the three-dimensional object OB. The intermediate layer MA is an area located between the surface layer SA and the internal layer IA in the stacking direction. In this embodiment, the intermediate layer MA includes an upper layer UA and a lower layer LA. The upper layer UA is located between the top layer TA and the internal layer IA in the stacking direction. The lower layer LA is located between the bottom layer BA and the internal layer IA in the stacking direction. Note that in this embodiment, the line widths of the paths included in the first discharge path PD1 to the fourth discharge path are all the same.

[0045] The side surface portion WA corresponds to the outer shell region that represents the outer shell of the three-dimensional object OB. The surface layer SA, the intermediate layer MA, and the inner layer IA each correspond to the infill region. The infill region is the region located inside the outer shell region when viewed in the stacking direction. In Figure 7, the outer shell region is indicated by diagonal hatching, and the infill region is indicated by dotted hatching.

[0046] In the modeling data, a movement path with a predetermined infill pattern, a predetermined filling rate, and a predetermined infill angle is generated in the infill area. The infill pattern represents the pattern of the movement path that fills the infill area. Examples of infill patterns include a zigzag pattern, a concentric pattern, a lattice pattern, a truss pattern, and a honeycomb pattern. In this embodiment, a zigzag pattern is used as the infill pattern. The infill angle represents the angle at which the infill pattern is arranged. Parameters related to the discharge path of the infill area, such as the infill pattern, the filling rate, and the infill angle, may be selectable by the user, or may be automatically determined without user selection.

[0047] In this embodiment, the filling rate of the surface layer SA is higher than that of the intermediate layer MA. More specifically, the second discharge path PD2 and the fourth discharge path are configured so that the filling rate of the surface layer SA is higher than that of the intermediate layer MA. Furthermore, the filling rate of the intermediate layer MA is higher than that of the internal layer IA. More specifically, the fourth discharge path and the third discharge path PD3 are configured so that the filling rate of the internal layer MA is higher than that of the internal layer IA. Increasing the filling rate of the surface layer SA can further improve the strength of the bottom surface of the three-dimensional object OB and can further reduce visibility of the interior through the bottom surface of the three-dimensional object OB. Meanwhile, because the internal layer IA is located inside the surface layer SA and the side surface portion WA, the filling rate of the internal layer IA has less of an effect on the strength and appearance of the three-dimensional object OB than the filling rate of the surface layer SA. Lowering the filling rate of the internal layer IA can further shorten the modeling time of the internal layer IA and further reduce consumption of the modeling material used to model the internal layer IA.

[0048] As shown in FIG. 8, the first discharge path PD1 for forming the side portion WA is configured as a path that makes one or more revolutions and continuously surrounds the infill region along the periphery of the three-dimensional object OB when viewed in the stacking direction. In the example of FIG. 8, the first discharge path PD1 is a path that makes one revolution. The number of revolutions of the first discharge path may be two or more. Increasing the number of revolutions of the first discharge path can further improve the strength of the side portion of the three-dimensional object OB and further reduce the visibility of the interior through the side portion of the three-dimensional object OB. Conversely, reducing the number of revolutions of the first discharge path can further increase the proportion of the internal layer IA in the three-dimensional object OB, thereby further shortening the printing time and reducing the consumption of printing material.

[0049] The process of acquiring the first data D1 is also referred to as the first acquisition process. The process of generating the second data D2 is also referred to as the second acquisition process. The process of generating the third data D3 is also referred to as the third acquisition process. The process of acquiring the fourth data D4 is also referred to as the fourth acquisition process. That is, in step S20 of FIG. 6, the first acquisition process, second acquisition process, third acquisition process, and fourth acquisition process are executed.

[0050] In step S30 of FIG. 6, the data generation unit 411 executes a first expansion process. In this embodiment, the data generation unit 411 executes the first expansion process to generate second shaping data in which at least a portion of the first shaping data has been changed, and acquires the generated second shaping data. The first expansion process is a process of expanding the first adjacent layer to a first overlapping region OA1 included in the internal layer IA. The first overlapping region OA1 is a region that overlaps with the side surface portion WA when viewed in the stacking direction. More specifically, the side surface portion WA contacts at least one of the upper and lower sides of the first overlapping region OA1 in the stacking direction. The first adjacent layer is the surface layer SA adjacent to the first overlapping region OA1 in the layer direction. In other words, the first adjacent layer and the first overlapping region OA1 are adjacent to each other in the layer direction. By expanding the first adjacent layer in the first expansion process, at least a portion of the original first overlapping region OA1 in the layer direction is replaced and reduced by the expanded first adjacent layer. In the first expansion process, the first adjacent layer may be expanded to at least a portion of the first overlapping area OA1. The portion of the first adjacent layer that is added by expanding the first adjacent layer is also referred to as the first added portion. The original portion of the first adjacent layer is also referred to as the first original portion. The process of expanding the first adjacent layer to the first overlapping area OA1 is also referred to as the first expansion process. Hereinafter, unless otherwise specified, the term "adjacent" simply means adjacent in the layer direction.

[0051] In the examples of FIGS. 7 and 8, the top layer TAa and the bottom layer BAa correspond to the first adjacent layer. The top layer TAa is adjacent to the first overlapping region OA1a included in the inner layer IAm. The side layer WAa included in the side portion WA contacts the +Z direction side of the first overlapping region OA1a from the +Z direction. The side layer WAa is included in the layer Ln one layer above the layer Lm. In other words, the side layer WAa is the layer one layer above the side layer WAm. The bottom layer BAa is adjacent to the first overlapping region OA1b. The side layer WAb contacts the -Z direction side of the first overlapping region OA1b from the -Z direction. The side layer WAb is included in the layer one layer below the layer including the bottom layer BAa. In this embodiment, since the first discharge path PD1 is a movement path for one circumference as described above, the widths of the first overlapping regions OA1a and OA1b in the X direction each correspond to the line width of the first discharge path PD1.

[0052] FIG. 9 is a diagram illustrating a first example of the first extension process in the first embodiment. FIG. 10 is a cross-sectional view taken along line XX in FIG. 9. FIG. 11 is a cross-sectional view taken along line XI-XI in FIG. 9. FIGS. 9 to 11 show second extension data SD2 generated based on the first extension data SD1 by the first extension process. The second extension data SD2 includes, in addition to the first data D1 and the fourth data D4, second data D2t, which is the second data D2 modified by the first extension process, and third data D3t, which is the third data D3 modified by the first extension process. FIG. 10 shows the layer Lm in the same manner as FIG. 8. FIG. 11 shows a layer Ln in addition to a portion of the layer Lm. The layer Ln includes a side layer WAa and an internal layer IAn. The internal layer IAn is the layer immediately above the internal layer IAm. FIGS. 9 to 11 show the expanded topmost layer ETAa, which is the topmost layer TAa extended by the first extension process. 10 and 11 also show the reduced inner layer RIAm, which is the inner layer IAm reduced by the first expansion process.

[0053] As shown in FIGS. 9 and 10, in the first expansion process, the top layer TAa is expanded to a first overlapping region OA1a. In this embodiment, the top layer TAa is expanded so that the entire area of ​​the first overlapping region OA1a is replaced by the first additional portion ETP1a of the top layer TAa. That is, the top layer TAa is expanded in the -X direction by an expansion width corresponding to the line width of the first discharge path PD1. In FIG. 10, the original first overlapping region OA1 is indicated by a dashed line. As shown in FIG. 9, the bottom layer BAa is expanded to a first overlapping region OA1b, substantially similar to the top layer TAa.

[0054] In this embodiment, the data generating unit 411 generates a new second ejection path that spans the first original portion and the first additional portion of the first adjacent layer, thereby expanding the first adjacent layer to the first overlapping area OA1. The data generating unit 411 also generates a new third ejection path in the inner layer IA that is reduced by the expansion of the first adjacent layer.

[0055] For example, as shown in FIG. 10, in the expanded top layer ETAa, a new second discharge path NPD2 is generated spanning the first original portion OTP1a of the top layer TAa and the first additional portion ETP1a of the top layer TAa. In this embodiment, the new second discharge path NPD2 is a movement path for printing the expanded top layer ETAa with the same infill pattern, filling rate, and infill angle as the second discharge path PD2. The line width of the new second discharge path NPD2 is the same as the line width of the second discharge path PD2. By generating the new second discharge path NPD2 in this manner, the second data D2 is changed to second data D2t including the new second discharge path NPD2. In addition, a new third discharge path NPD3 is generated in the reduced internal layer RIAm adjacent to the expanded top layer ETAa. In this embodiment, the new third discharge path NPD3 is a movement path for forming the reduced internal layer RIAm with the same infill pattern, filling rate, and infill angle as the third discharge path PD3. The line width of the new third discharge path NPD3 is the same as the line width of the third discharge path PD3. By generating the new third discharge path NPD3 in this manner, the third data D3 is changed to third data D3t that includes the new third discharge path NPD3.

[0056] The present inventors have found that the position of the boundary BD1 between the internal layer IA and the surface layer SA in the layer direction affects the strength of the three-dimensional object OB. More specifically, for example, in FIGS. 7 and 8 , the boundary BD1a between the internal layer IAm and the top layer TAa in the X direction is located at a position that is linearly connected in the Z direction to the outer surface of the side layer WAa on the +X direction side. On the other hand, in FIGS. 9 to 11 , the boundary BD1a is located closer to the −X direction than the outer surface of the side layer WAa on the +X direction side. That is, in FIGS. 7 and 8 , the boundary BD1a is closer to the outer surface of the three-dimensional object OB than in FIGS. 9 to 11 . The present inventors have found that when the boundary BD1 is relatively close to the outer surface of the three-dimensional object OB, an external force applied to the three-dimensional object OB is more likely to be applied to the boundary BD1, which may locally reduce the strength of the portion of the three-dimensional object OB near the boundary BD1 compared to the strength of other portions. 7 and 8, compared to FIGS. 9 to 11, when an external force is applied to the three-dimensional object OB, stress that separates the inner layer IAm and the uppermost layer TAa from the upper end side of the boundary BD1a is more likely to occur at the boundary BD1a. In contrast, as shown in FIGS. 9 to 11, by performing the first expansion process, the boundary BD1 moves toward the inner layer IA in the layer direction, thereby moving the boundary BD1 away from the outer surface of the three-dimensional object OB. As a result, the strength of the portion of the three-dimensional object OB near the boundary BD1 is less likely to decrease locally.

[0057] 6, the control unit 300 of the three-dimensional printing apparatus 100 acquires the second printing data generated in step S30 from the information processing device 400. In step S50, the control unit 300 controls the discharging unit 60 and the moving mechanism 230 in accordance with the second printing data acquired in step S40, and prints a three-dimensional object on the printing surface 211 of the stage 210.

[0058] FIG. 12 is a diagram illustrating a second example of the first extension process in the first embodiment. FIG. 12 illustrates how the second formation data SD2b is generated based on the first formation data SD1b by the first extension process. Unlike the first discharge path PD1 shown in FIG. 8, the first discharge path PD1b in the first formation data SD1b is a movement path that covers two revolutions. Therefore, the width of the first overlapping region OA1a in FIG. 12 in the X direction corresponds to twice the line width of the first discharge path PD1b. In the example of FIG. 12, the extension widths of the top layer TAa and the bottom layer BAa in the first extension process each correspond to twice the line width of the first discharge path PD1b and correspond to the width of the first overlapping region OA1a in the X direction.

[0059] According to the data generation method of the present embodiment described above, the first expansion step is performed to expand the first adjacent layer included in the surface layer SA to the first overlapping area OA1 included in the internal layer IA. As a result, the boundary BD1 can be moved away from the outer surface of the three-dimensional object OB, thereby improving the strength of the three-dimensional object OB.

[0060] Furthermore, by expanding the first adjacent layer, at least a portion of the side surface portion WA that originally contacted the first overlapping region OA1 can be brought into contact with the first adjacent layer. That is, at least a portion of the side surface portion WA that originally contacted the internal layer IA can be brought into contact with the surface layer SA and supported by the surface layer SA. In this embodiment, the filling rate of the surface layer SA is higher than the filling rate of the internal layer IA, thereby improving the adhesion between the side surface portion WA and the infill region in the stacking direction. As a result, the strength of the three-dimensional object OB can be improved. In particular, in this embodiment, the surface layer SA as the first adjacent layer is expanded to cover the entire first overlapping region OA1. More specifically, in the example of FIG. 12, the expansion width of the surface layer SA is twice the line width of the first discharge path PD1, corresponding to the number of revolutions of the first discharge path PD1. Therefore, the adhesion between the side surface portion WA and the infill region in the stacking direction can be further improved, and the strength of the three-dimensional object OB can be further improved.

[0061] Furthermore, in this embodiment, in the first expansion step, a new second discharge path NPD2 is generated across the first original portion and the first additional portion, thereby expanding the first adjacent layer. Therefore, the first original portion and the first additional portion can be integrally formed by the new second discharge path NPD2. As a result, the strength of the three-dimensional object OB can be further improved.

[0062] This embodiment also includes a fourth acquisition step of acquiring fourth data D4 for forming the intermediate layer MA of the three-dimensional object OB. Therefore, the surface layer SA and the internal layer IA can be appropriately connected in the stacking direction via the intermediate layer MA. In particular, in this embodiment, the packing rate of the surface layer SA is higher than that of the intermediate layer MA, which in turn is higher than that of the internal layer IA. As a result, the packing rate can be gradually changed in the stacking direction between the surface layer SA and the internal layer IA, thereby preventing a local decrease in strength due to a sudden change in packing rate between the surface layer SA and the internal layer IA. Furthermore, by disposing the upper layer UA between the top layer TA and the internal layer IA, it is possible to prevent the molding material for forming the top layer TA from dripping into the gap in the internal layer IA during three-dimensional printing, thereby improving the shape of the three-dimensional object OB during and after printing.

[0063] B. Second embodiment: FIG. 13 is a flowchart of the modeling process in the second embodiment. FIG. 14 is a diagram illustrating a first example of the second extension process in the second embodiment. Unlike the first embodiment, the second extension process is further executed in the second embodiment. In the example of FIG. 14, the first extension process and the second extension process are executed on the first modeling data SD1b, thereby generating the second modeling data SD2c. The second modeling data SD2c includes the first data D1, the second data D2t, and the third data D3t, as well as the fourth data D4t, which is the fourth data D4 changed by the second extension process. The three-dimensional modeling device 100 and the information processing device 400 in the second embodiment are similar to those in the first embodiment unless otherwise described.

[0064] In step S35 of FIG. 13, the data generation unit 411 executes a second expansion process. The second expansion process expands the second adjacent layer to the second overlapping region OA2 included in the inner layer IA. The second overlapping region OA2 is a region that overlaps with the side surface portion WA when viewed in the stacking direction. The second adjacent layer is the intermediate layer MA that is adjacent to the second overlapping region OA2 in the layer direction. That is, the second adjacent layer and the second overlapping region OA2 are adjacent to each other in the layer direction. By the second expansion process, at least a portion of the original second overlapping region OA2 in the layer direction is replaced and reduced by the expanded second adjacent layer. The portion of the second adjacent layer that is added by expanding the second adjacent layer is also referred to as the second added portion. The original portion of the second adjacent layer is also referred to as the second original portion. The process of expanding the second adjacent layer to the second overlapping region OA2 is also referred to as the second expansion process.

[0065] In the example of FIG. 14, the upper layer UAa and the lower layer LAa in the first modeling data SD1b shown in the upper part of FIG. 14 correspond to the second adjacent layer. The upper layer UAa is adjacent to the second overlapping region OA2a included in the internal layer IAL. The upper layer UAa and the internal layer IAL are included in the layer LL, which is the layer immediately below the layer Lm. The first overlapping region OA1a is adjacent to the +Z direction side of the second overlapping region OA2a from the +Z direction side. The lower layer LAa is adjacent to the second overlapping region OA2b. The first overlapping region OA1b is adjacent to the -Z direction side of the second overlapping region OA2b from the -Z direction side. Note that, in the stacking direction, the upper layer UAb is located between the uppermost layer TAb and the internal layer IA. Also, in the stacking direction, the lower layer LAb is located between the lowermost layer BAb and the internal layer IA. The upper layer UAb and the lower layer LAb do not correspond to the second adjacent layer.

[0066] As shown in the lower part of FIG. 14, in the second expansion process, the upper layer UAa is expanded to the second overlapping region OA2a. In this embodiment, the upper layer UAa is expanded so that the entire area of ​​the second overlapping region OA2a is replaced by the expanded portion EUP2a of the upper layer UAa. That is, in the example of FIG. 14, the upper layer UAa is expanded in the -X direction by an expansion width equivalent to twice the line width of the first discharge path PD1b. The lower part of FIG. 14 shows the expanded upper layer EUAa, which is the upper layer UAa expanded by the second expansion process. The lower part of FIG. 14 also shows the reduced internal layer RIAL, which is the internal layer IAL reduced by the expansion of the upper layer UAa. Note that, in a manner substantially similar to the upper layer UAa, the lower layer LAa is expanded to the second overlapping region OA2b.

[0067] Although not shown, in this embodiment, the data generation unit 411 expands the second adjacent layer to the second overlapping area OA2 by generating a new fourth discharge path spanning the second original portion and the second additional portion of the second adjacent layer, similar to the case of the first adjacent layer shown in FIG. 10 . In this embodiment, the new fourth discharge path is a movement path for forming the expanded second adjacent layer with the same infill pattern, filling rate, and infill angle as the original fourth discharge path. The line width of the new fourth discharge path is the same as the line width of the original fourth discharge path. By generating the new fourth discharge path in this manner, the fourth data D4 is changed to fourth data D4t including the new fourth discharge path. In addition, the data generation unit 411 generates a new third discharge path for the layer of the internal layer IA that is reduced by the expansion of the second adjacent layer. As a result, in this embodiment, the third data D3t includes the new third discharge path obtained by the first expansion process and the new third discharge path obtained by the second expansion process.

[0068] FIG. 15 is a diagram illustrating a second example of the second extension process in the second embodiment. FIG. 15 illustrates how the second extension process generates second modeling data SD2d based on the first modeling data SD1b. Unlike the example of FIG. 14, the extension widths of the upper layer UAa and the lower layer LAa in the second extension process are equal to the line width of the first discharge path PD1b. That is, in the example of FIG. 15, the upper layer UAa and the lower layer LAa are extended to the center positions in the X direction of the side layer WAa and WAb, respectively. Compared to the example of FIG. 14, the example of FIG. 15 has a larger proportion of the internal layer IA in the three-dimensional modeled object OB, which allows for further reductions in the modeling time and consumption of modeling materials in three-dimensional modeling. On the other hand, in the example of Figure 14, the expansion width of the surface layer SA as the first adjacent region corresponds to the expansion width of the intermediate layer MA as the second adjacent region, so compared to the example of Figure 15, the expanded surface layer SA and the internal layer IA can be more appropriately connected via the expanded intermediate layer MA.

[0069] According to the data generation method of the second embodiment described above, the second expansion step is performed to expand the second adjacent layer included in the surface layer SA to the second overlapping region OA2 included in the internal layer IA and overlapping the side surface portion WA when viewed in the stacking direction. Therefore, the second adjacent layer can be expanded to correspond to the first adjacent layer expanded in the first expansion step. As a result, the expanded first adjacent layer and the internal layer IA can be appropriately connected in the stacking direction via the expanded second adjacent layer.

[0070] Furthermore, in this embodiment, in the second expansion step, a new fourth discharge path is generated that spans the second original portion and the second additional portion, thereby expanding the second adjacent layer. Therefore, the second original portion and the second additional portion can be integrally formed by the new fourth discharge path. As a result, the strength of the three-dimensional object OB can be further improved.

[0071] C. Third embodiment: FIG. 16 is a diagram illustrating an example of the first expansion process in the third embodiment. Unlike the first embodiment, in the third embodiment, the first adjacent layer is expanded by expanding the line width of the first adjacent path in the first expansion process. The first adjacent path is a movement path of the second discharge path that is adjacent to the first overlapping area OA1 in the layer direction. In the example of FIG. 16, the first expansion process is performed on the first modeling data SD1c, thereby generating second modeling data SD2d. The three-dimensional modeling device 100 and the information processing device 400 in the third embodiment are similar to those in the first embodiment in terms of the aspects not specifically described.

[0072] The upper part of Fig. 16 shows a second discharge path PD2b for forming the top layer TAa. In the example of Fig. 16, as shown in the upper part of Fig. 16, the second discharge path PD2b represents a zigzag infill pattern that moves back and forth in the Y direction while progressing in the X direction. The second discharge path PD2b includes a first adjacent path AP1. The first adjacent path AP1 is a movement path that extends in the Y direction from the end of the top layer TAa on the +Y direction side to the end on the -Y direction side. The first adjacent path AP1 is adjacent to the inner layer IAm from the +X direction side.

[0073] As shown in the lower part of FIG. 16 , in the first expansion process, the data generation unit 411 expands the line width of the first adjacent path AP1 toward the first overlapping region OA1, thereby expanding the top layer TAa, which is the first adjacent layer. In the example of FIG. 16 , the first adjacent path AP1 is expanded in the −X direction to generate the expanded first adjacent path EAP1. The original line width of the first adjacent path AP1 is line width W1, similar to the other movement paths included in the second discharge path PD2b. The expanded line width of the first adjacent path EAP1 is line width W2. The line width W2 is the sum of the line width W1 and the width of the first overlapping region OA1a in the X direction, i.e., the line width of the first discharge path PD1b. The second discharge path PD2b including the expanded first adjacent path EAP1 is also referred to as the expanded second discharge path EPD2b.

[0074] According to the data generation method of the third embodiment described above, in the first expansion step, the line width of the first adjacent path AP1 of the second discharge path PD2b that is adjacent to the first overlapping area OA1 in the layer direction is expanded, thereby expanding the first adjacent layer. Therefore, the first original portion and the first additional portion can be integrally formed by the expanded second discharge path EPD2b. As a result, the strength of the three-dimensional object OB can be further improved. Furthermore, in this embodiment, in the first expansion step, instead of generating the entire expanded second discharge path EPD2b from scratch, only the first adjacent path AP1 is changed to expand the line width of the first adjacent path AP1, thereby reducing the processing load on the data generation unit 411 in the first expansion step.

[0075] In another embodiment, the second adjacent layer may be expanded by expanding the second adjacent path to the second overlapping region in the second expansion process, in a manner similar to the first adjacent layer being expanded by expanding the first adjacent path to the first overlapping region in the first expansion process. The second adjacent path is a movement path among the fourth discharge paths that is adjacent to the second adjacent layer in the layer direction. This allows the second original portion and the second additional portion to be integrally formed by the fourth discharge path including the expanded second adjacent path. As a result, the strength of the three-dimensional object OB can be further improved. In this case, instead of generating a new expanded fourth discharge path in its entirety in the second expansion process, only the second adjacent path is changed to expand the line width of the second adjacent path, thereby reducing the processing load on the data generation unit 411 in the second expansion process.

[0076] D. Fourth embodiment: FIG. 17 is a diagram illustrating a first example of the first extension process in the fourth embodiment. Unlike the first embodiment, in the first extension process, the first adjacent layer is extended by generating a first additional path in the first additional portion. In the example of FIG. 17, the first extension process is performed on the first modeling data SD1d, thereby generating second modeling data SD2e. The three-dimensional modeling device 100 and the information processing device 400 in the third embodiment are similar to those in the first embodiment in terms of the aspects not specifically described.

[0077] The first modeling data SD1d includes path information for the first discharge path PD1b, similar to the first modeling data SD1b shown in Fig. 12. The first modeling data SD1d also includes path information for the second discharge path PD2b, similar to the first modeling data SD1c shown in Fig. 16. In the upper part of Fig. 17, of the first discharge path PD1, the first path P1 and the second path P2 that are in contact with the first overlapping region OA1a in the stacking direction are schematically shown by dashed-dotted lines and cross-hatching. The first path P1 and the second path P2 are movement paths that extend in the Y direction.

[0078] In the example of FIG. 17, as shown in the lower part of FIG. 17, in the first extension process, the data generator 411 extends the top layer TAa to the first overlapping area OA1a by additionally generating a first additional path AD1 in the first additional portion ETP1a. In this embodiment, as in the first embodiment, the top layer TAa is extended so that the entire area of ​​the first overlapping area OA1a is replaced by the first additional portion ETP1a of the top layer TAa. The first additional path AD1 is a movement path extending in the Y direction. The first additional path AD1 is included in the changed second data D2t.

[0079] In this embodiment, the data generation unit 411 also sets the line width of the first additional path to be different from the line width of the stacking path. The stacking path is a movement path of the first discharge path PD1 that is in contact with the first additional portion in the stacking direction. In the example of FIG. 17, the first path P1 and the second path P2 correspond to the stacking path for the first additional portion ETP1a. In the example of FIG. 17, the line width W2 of the first additional path AD1 is larger than the line width W1 of the first path P1 and the second path P2.

[0080] FIG. 18 is a diagram illustrating a second example of the first extension process in the fourth embodiment. In the example of FIG. 18, the first extension process is performed on the first formation data SD1d to generate second formation data SD2f. In the example of FIG. 18, as in the example of FIG. 17, the data generation unit 411 sets the line width of the first additional path AD1b to be different from the line widths of the first path P1 and the second path P2, which are stacking paths for the first additional portion ETP1a. However, the line width W3 of the first additional path AD1b is smaller than the line width W2 of the first path P1 and the second path P2. Specifically, the line width W3 is two-thirds of the line width W2. In this embodiment, the line width W3 is determined as the width of the first additional portion ETP1a in the X direction divided by a number that is larger than the number of stacking paths for the first additional portion ETP1a and is different from a multiple of the number of stacking paths for the first additional portion ETP1a. This makes it possible to prevent gaps between the movement paths included in the first additional path AD1b and gaps between the stacking paths from being connected in the stacking direction.

[0081] According to the data generation method of the fourth embodiment described above, in the first expansion process, a first additional path for modeling the first additional portion is generated in the first additional portion, thereby expanding the first adjacent layer. Therefore, the first adjacent layer can be expanded by adding an arbitrary movement path for modeling the first additional portion to the first additional portion. Furthermore, compared to the case where a new second discharge path spanning the first additional portion and the first original portion is generated, the processing load on the data generation unit 411 in the first expansion process can be reduced.

[0082] Furthermore, in this embodiment, the line width of the first additional path generated in the first additional portion is different from the line width of the stacking path for that first additional portion. This prevents a decrease in strength due to the gap in the layer direction in the first additional portion and the gap in the layer direction in the side portion being connected in the stacking direction. For example, in the example of FIG. 17 , the line width W1 of the first additional path AD1 is larger than the line width W2 of the first path P1 and the second path P2 that contact the first additional portion ETP1a in the stacking direction. As a result, the first additional path AD1 is generated so as to straddle the first path P1 and the second path P2 in the X direction when viewed in the stacking direction. This prevents the gap in the layer direction between the first path P1 and the second path P2 and the gap in the layer direction in the first additional portion ETP1a from being connected in the stacking direction. 18, the line width W3 of the first additional path AD1b is smaller than the line width W2 and is set so as to prevent gaps between the movement paths included in the first additional path AD1b from being connected in the stacking direction with gaps between the stacking paths. Therefore, it is possible to prevent gaps between the first path P1 and the second path P2 in the layer direction from being connected in the stacking direction with gaps in the layer direction in the first additional part ETP1a.

[0083] In another embodiment, in substantially the same way as the first adjacent layer is expanded by generating a first additional path in the first additional portion in the first expansion process, the second adjacent layer may be expanded to the second overlap region by generating a second additional path in the second additional portion. The second additional path is a movement path for forming the second additional portion. The second additional path is included in the changed fourth data. In this way, the second adjacent layer can be expanded by adding an arbitrary movement path for forming the second additional portion to the second added portion. Furthermore, compared to the case where a new fourth discharge path spanning the second added portion and the second original portion is generated, the processing load on the data generation unit 411 in the second expansion process can be reduced.

[0084] E. Fifth embodiment: FIG. 19 is a diagram illustrating an example of the first extension process in the fifth embodiment. In the example of FIG. 19, the first extension process is performed on the first modeling data SD1d, thereby generating second modeling data SD2g. The first additional path AD1c in the fifth embodiment is a movement path that intersects with the stacking path for the first additional portion ETP1a. Unlike the second discharge path PD2b, the first additional path AD1c represents an infill pattern that moves back and forth in the X direction while progressing in the Y direction. As a result, the first additional path AD1c intersects with the extension direction of the stacking path for the first additional portion ETP1a two or more times. The three-dimensional modeling device 100 and the information processing device 400 in the fifth embodiment, except for the points not specifically described, are the same as those in the fourth embodiment.

[0085] According to the data generating method of the fifth embodiment described above, the first additional path AD1c, when viewed in the stacking direction, intersects with the movement path of the first discharge path PD1 that contacts the first additional portion ETP1a in the stacking direction. This makes it possible to suppress a decrease in strength caused by the gap in the layer direction in the first additional portion and the gap in the layer direction in the side portion being connected in the stacking direction.

[0086] F. Sixth embodiment: FIG. 20 is a flowchart of the modeling process in the sixth embodiment. FIG. 21 is a diagram illustrating an example of the first extension process and the second extension process in the sixth embodiment. As shown in FIG. 20, unlike the second embodiment, the modeling process in this embodiment includes a first determination process and a second determination process. In FIG. 20, the same steps as in FIG. 13 are denoted by the same reference numerals as in FIG. 13. In the example of FIG. 21, the first extension process and the second extension process are performed on the first modeling data SD1b, thereby generating the second modeling data SD2h. The three-dimensional modeling device 100 and the information processing device 400 in the sixth embodiment are similar to those in the second embodiment in respects that are not specifically described.

[0087] In step S29 of FIG. 20, the data generation unit 411 executes a first determination process. The first determination process is a process for individually determining the expansion width in the layer direction of the top layer TA as the first adjacent layer in the first expansion process and the expansion width in the layer direction of the bottom layer BA as the first adjacent layer in the first expansion process. In the first determination process, the expansion width of the top layer TA is determined before the top layer TA is expanded by the first expansion process. Also, in the first determination process, the expansion width of the bottom layer BA is determined before the bottom layer BA is expanded by the first expansion process. In this embodiment, step S29 is executed prior to the first expansion process of step S30b. In this embodiment, in step S29, the data generation unit 411 first acquires the expansion width of the top layer TA and the expansion width of the bottom layer BA input by the user via the input device 470. The data generation unit 411 then determines each acquired expansion width as the expansion width of the topmost layer TA and the expansion width of the bottommost layer BA in the first expansion process. Note that if the three-dimensional object OB includes multiple topmost layers TA as first adjacent layers, an expansion width may be determined for each topmost layer TA individually, or a common expansion width may be determined for all topmost layer TAs. The same applies to the bottommost layer BA. Also, one of the expansion widths of the topmost layer TA and the bottommost layer BA may be determined to be zero.

[0088] In step S30b, the data generation unit 411 executes the first expansion process so that the top layer TA and the bottom layer BA are expanded by the expansion widths determined in step S29.

[0089] In step S34, the data generation unit 411 executes a second determination process. The second determination process is a process for individually determining the expansion width in the layer direction of the upper layer UA as the second adjacent layer in the second extension process and the expansion width in the layer direction of the lower layer LA as the second adjacent layer in the second extension process. In the second determination process, the expansion width of the upper layer UA is determined before the upper layer UA is expanded by the second extension process. Also, in the second determination process, the expansion width of the lower layer LA is determined before the lower layer LA is expanded by the second extension process. In this embodiment, step S34 is executed before the second extension process of step S35b. In step S35b, the data generation unit 411 executes the second extension process so that the upper layer UA and the lower layer LA are expanded by the expansion widths determined in step S34. In this embodiment, in step S34, the data generation unit 411 first acquires the expansion widths of the upper layer UA and the lower layer LA input by the user via the input device 470. Then, the data generation unit 411 determines each acquired expansion width as the expansion width of the upper layer UA and the expansion width of the lower layer LA in the first expansion process, respectively. Note that if the three-dimensional object OB includes multiple upper layer UAs as second adjacent layers, an expansion width may be determined individually for each upper layer UA, or a common expansion width may be determined for all upper layer UAs. The same applies to the lower layer LA. Also, one or both of the expansion widths of the upper layer UA and the lower layer LA may be determined to be zero.

[0090] In the example of Figure 21, the expansion width of the top layer TAa and the upper layer UAa is expansion width WE1. The expansion width WE1 corresponds to the line width of the first discharge path PD1. The expansion width of the bottom layer BAa and the lower layer LAa is expansion width WE2. The expansion width WE2 corresponds to twice the line width of the first discharge path PD1.

[0091] According to the data generation method of the sixth embodiment described above, the expansion width of the top layer TA as the first adjacent layer in the first expansion process and the expansion width of the bottom layer BA as the first adjacent layer in the first expansion process are determined individually. Therefore, in the first expansion process, the top layer TA and the bottom layer BA can be expanded by appropriate expansion widths. For example, in the example of FIG. 21 , by increasing the expansion width of the bottom layer BAa, the bottom layer BAa can be expanded further toward the −X direction, i.e., toward the first portion OP1. As a result, during or after modeling, tilt of the bottom layer BAa such that the second portion OP2 side of the bottom layer BAa sags downward can be suppressed, thereby stabilizing the shape of the three-dimensional object OB. On the other hand, by decreasing the expansion width of the top layer TAa, the proportion of the internal layer IA in the three-dimensional object OB can be increased, thereby further reducing the modeling time and the consumption of modeling materials.

[0092] In addition, in this embodiment, the expansion width of the upper layer UA as the second adjacent layer in the second expansion process and the expansion width of the lower layer LA as the second adjacent layer in the second expansion process are determined separately. Therefore, in the second expansion process, the upper layer UA and the lower layer LA can be expanded to appropriate expansion widths. For example, in the example of FIG. 21, by determining the expansion width of the lower layer LAa to expansion width WE2 corresponding to the expansion width of the bottom layer BAa, the expanded bottom layer BAa and the internal layer IA can be more appropriately connected via the expanded lower layer LAa. Furthermore, by determining the expansion width of the upper layer UAa to expansion width WE1 corresponding to the expansion width of the top layer TAa, the expanded top layer ETAa and the internal layer IA can be more appropriately connected via the expanded upper layer EUAa.

[0093] G. Other Embodiments: (G-1) In the fifth embodiment, the line width of the first additional path generated in the first additional portion is different from the line width of the stacked path that contacts the first additional portion in the stacking direction, but may be the same.

[0094] (G-2) In each of the above embodiments, the surface layer SA may include only one of the top layer TA and the bottom layer BA. More specifically, for example, a layer of the three-dimensional object OB that is not in contact with another layer above may be formed as an internal layer IA rather than as an uppermost layer TA. Furthermore, for example, a layer of the three-dimensional object OB that is not in contact with another layer below may be formed as an internal layer IA rather than as a bottommost layer BA.

[0095] (G-3) In the sixth embodiment, only one of the first determination process and the second determination process may be executed. That is, only one of the first expansion process may be executed: determining the expansion width of the top layer TA and the bottom layer BA individually; and the second expansion process may be executed: determining the expansion width of the upper layer UA and the bottom layer LA individually.

[0096] (G-4) In the sixth embodiment, the first determination process determines the expansion widths of the top layer TA and the bottom layer BA in the first expansion step based on the expansion width input by the user. Alternatively, the expansion widths of the top layer TA and the bottom layer BA in the first determination process may be determined automatically and individually by the data generation unit 411, without relying on the user. For example, the expansion widths of the top layer TA and the bottom layer BA may be determined based on the layer-wise width of the first overlapping area OA1 adjacent to the top layer TA or the bottom layer BA. In this case, for example, the larger the layer-wise width of the first overlapping area OA1 adjacent to the top layer TA or the bottom layer BA, the larger the expansion width of the top layer TA or the bottom layer BA may be. This allows the expanded top layer TA or the expanded bottom layer BA to more appropriately support the side layer adjacent to the top layer TA or the bottom layer BA in the stacking direction. Furthermore, for example, the expansion width of the bottom layer BA may always be determined to be larger than the expansion width of the top layer TA. Furthermore, in a manner similar to the above, in the second determination process, the expansion widths of the upper layer UA and the lower layer LA may be determined automatically and individually by the data generation unit 411, without relying on the user. For example, the data generation unit 411 may determine the expansion width of the upper layer UA so as to correspond to the expansion width of the top layer TA in the first extension process, and may determine the expansion width of the lower layer LA so as to correspond to the expansion width of the bottom layer BA in the first extension process.

[0097] (G-5) In the above embodiments, the intermediate layer MA may include only one of the upper layer UA and the lower layer LA. Furthermore, the three-dimensional object OB does not have to include the intermediate layer MA.

[0098] (G-6) In each of the above embodiments, the data generation unit 411 acquires each piece of data, namely, the first data D1 to the fourth data D4, by generating each piece of data included in the first formation data SD1 in each of the first to fourth acquisition processes. However, some or all of the first data D1 to the fourth data D4 may be acquired from, for example, the storage device 430, an external recording medium, or a computer.

[0099] (G-7) In each of the above embodiments, the filling rate of the surface layer SA is higher than that of the intermediate layer MA, which is in turn higher than that of the internal layer IA. In contrast, the filling rate of the surface layer SA may be the same as or lower than that of the intermediate layer MA. Furthermore, the filling rate of the intermediate layer MA may be the same as or lower than that of the internal layer IA. Furthermore, the filling rate of the surface layer SA may be the same as or lower than that of the internal layer IA.

[0100] (G-8) In each of the above embodiments, the molding unit 110 plasticizes the material using the flat screw 40. However, the molding unit 110 may also plasticize the material by, for example, rotating an in-line screw. Alternatively, the molding unit 110 may also plasticize the filament-shaped material using a heater.

[0101] (G-9) In the above embodiments, a material extrusion method for laminating plasticized material has been described as an example, but the present disclosure can be applied to various methods, such as an inkjet method, a DMD (Direct Metal Deposition) method, and a binder jet method.

[0102] H. Other forms: The present disclosure is not limited to the above-described embodiments and can be realized in various forms without departing from the spirit thereof. For example, the present disclosure can also be realized in the following forms. The technical features in the above embodiments corresponding to the technical features in each form described below can be appropriately replaced or combined to solve some or all of the problems of the present disclosure or to achieve some or all of the effects of the present disclosure. Furthermore, if a technical feature is not described as essential in this specification, it can be appropriately deleted.

[0103] (1) According to one aspect of the present disclosure, there is provided a data generation method for generating modeling data for forming a three-dimensional object by stacking layers of modeling material ejected from an ejection unit moving along a movement path. This data generation method includes a first acquisition step of acquiring first data including information on a first discharge path that represents the movement path for forming the side portion of the three-dimensional object; a second acquisition step of acquiring second data including information on a second discharge path that represents the movement path for forming a surface layer of the three-dimensional object that is not in contact with other layers on at least one of the upper and lower sides in the layer stacking direction, and that is different from the side portion; a third acquisition step of acquiring third data including information on a third discharge path that represents the movement path for forming an internal layer of the three-dimensional object that is located inside the side portion and the surface layer; and a first expansion step of expanding a first adjacent layer that is included in the surface layer and adjacent to the first overlapping region in a layer direction perpendicular to the stacking direction, to a first overlapping region that is included in the internal layer and that overlaps the side portion when viewed in the stacking direction. According to this embodiment, the boundary between the inner layer and the surface layer in the layer direction is moved toward the inner layer in the layer direction by expanding the first adjacent layer, which results in the boundary being spaced farther from the outer surface of the three-dimensional structure, thereby improving the strength of the three-dimensional structure.

[0104] (2) In the above embodiment, the first expansion step may expand the first adjacent layer by generating a new second discharge path that spans the original portion of the first adjacent layer and the first additional portion of the first adjacent layer that is added by the expansion. According to this embodiment, the original portion of the first adjacent layer and the first additional portion can be integrally molded by the new second discharge path, thereby further improving the strength of the three-dimensional object.

[0105] (3) In the above embodiment, the first expansion step may expand the first adjacent layer by expanding the line width of the movement path of the second discharge path that is adjacent to the first overlap region in the layer direction. According to this embodiment, the first original portion and the first additional portion of the first adjacent layer can be integrally formed by the second discharge path that includes the movement path with the expanded line width. As a result, the strength of the three-dimensional object can be further improved.

[0106] (4) In the above embodiment, in the first expansion step, the first adjacent layer may be expanded by generating, in the first additional portion, a first additional path, which is the movement path for forming a first additional portion of the first adjacent layer that is added by expansion. According to this embodiment, the first adjacent layer can be expanded by adding, to the first additional portion, an arbitrary movement path for forming the first additional portion.

[0107] (5) In the above embodiment, the line width of the first additional path may be different from the line width of the movement path of the first discharge path that contacts the first additional portion in the stacking direction. This embodiment can suppress a decrease in strength caused by a gap in the layer direction in the first additional portion and a gap in the layer direction in the side portion being connected in the stacking direction.

[0108] (6) In the above embodiment, when viewed in the stacking direction, the first additional path may intersect with the movement path of the first discharge path that contacts the first additional portion in the stacking direction. This embodiment can suppress a decrease in strength caused by a gap in the layer direction in the first additional portion and a gap in the layer direction in the side portion being connected in the stacking direction.

[0109] (7) In the above embodiment, the surface layer may include a top layer that is not in contact with other layers above and a bottom layer that is not in contact with other layers below, and the expansion width of the top layer in the layer direction in the first expansion step and the expansion width of the bottom layer in the layer direction in the first expansion step may be determined separately. According to this embodiment, the top layer and the bottom layer can be expanded by appropriate expansion widths in the first expansion step.

[0110] (8) In the above aspect, a fourth acquisition step may be provided for acquiring fourth data including information on a fourth discharge path that represents the movement path for forming an intermediate layer of the three-dimensional object that is located between the surface layer and the internal layer in the stacking direction. According to this aspect, the surface layer and the internal layer can be appropriately connected in the stacking direction via the intermediate layer.

[0111] (9) The above embodiment may further include a second expansion step of expanding a second adjacent layer included in the intermediate layer, the second adjacent layer being adjacent to the second overlapping region in the layer direction, up to a second overlapping region in the internal layer that overlaps the side portion when viewed in the stacking direction. According to this embodiment, the second adjacent layer can be expanded corresponding to the first adjacent layer expanded in the first expansion step. As a result, the expanded first adjacent layer and the internal layer can be appropriately connected in the stacking direction via the expanded second adjacent layer.

[0112] (10) In the above embodiment, the second expansion step may expand the second adjacent layer by generating a new fourth discharge path that spans the original portion of the second adjacent layer and the second additional portion of the second adjacent layer that is added by the expansion. According to this embodiment, the original portion of the second adjacent layer and the second additional portion can be integrally molded by the new fourth discharge path. As a result, the strength of the three-dimensional object can be further improved.

[0113] (11) In the above embodiment, the second expansion step may expand the second adjacent layer by expanding the line width of the movement path of the fourth discharge path that is adjacent to the second adjacent layer in the layer direction. According to this embodiment, the original portion and the second additional portion of the second adjacent layer can be integrally formed by the fourth discharge path that includes the movement path with the expanded line width. As a result, the strength of the three-dimensional object can be further improved.

[0114] (12) In the above aspect, in the second expansion step, the second adjacent layer may be expanded by generating, in the second additional portion, a second additional path that is the movement path for forming a second additional portion of the second adjacent layer that is added by the expansion. According to this aspect, the second adjacent layer can be expanded by adding, to the second additional portion, an arbitrary movement path for forming the second additional portion.

[0115] (13) In the above embodiment, the surface layer includes a top layer that is not in contact with any other layer above and a bottom layer that is not in contact with any other layer below, the intermediate layer includes an upper layer located between the top layer and the internal layer in the stacking direction and a lower layer located between the bottom layer and the internal layer in the stacking direction, and the expansion width of the upper layer in the layer direction in the second expansion step and the expansion width of the lower layer in the layer direction in the second expansion step may be determined separately. According to this embodiment, the upper layer and the lower layer can be expanded by appropriate expansion widths in the second expansion step.

[0116] (14) In the above embodiment, the surface layer may have a higher packing density than the intermediate layer, and the intermediate layer may have a higher packing density than the internal layer. This allows the packing density to be varied stepwise in the stacking direction between the surface layer and the internal layer, thereby preventing a local decrease in strength due to a sudden change in packing density between the surface layer and the internal layer.

[0117] The present disclosure is not limited to the above-described data generation method, but can be realized in various forms, such as a method for manufacturing a three-dimensional object, a three-dimensional printing system, an information processing device, a computer program, and a non-transitory tangible recording medium on which a computer program is recorded in a computer-readable manner. [Explanation of symbols]

[0118] 10...3D modeling system, 20...material supply section, 22...communicating passage, 30...plasticizing section, 31...screw case, 32...drive motor, 40...flat screw, 42...groove section, 43...ridge section, 44...material inlet, 46...center section, 47...upper surface, 48...lower surface, 50...barrel, 52...upper surface, 54...guide groove, 56...communicating hole, 58...barrel heater, 60...discharge section, 61...nozzle, 62...nozzle opening, 65...flow path, 70...discharge adjustment section, 74...first drive section, 75...suction section, 7 6...second drive unit, 77...discharge control unit, 100...three-dimensional modeling apparatus, 110...modeling unit, 210...stage, 211...modeling surface, 212...stage heater, 230...movement mechanism, 300...control unit, 310...processor, 320...storage device, 400...information processing device, 410...CPU, 411...data generation unit, 420...memory, 430...storage device, 440...communication interface, 450...input / output interface, 460...bus, 470...input device, 480...display unit

Claims

1. A data generation method for generating modeling data for forming a three-dimensional object by stacking layers of modeling material discharged from a discharging unit that moves along a movement path, the method comprising: a first acquisition step of acquiring first data including information on a first discharge path that represents the movement path for forming a side surface portion of the three-dimensional object; a second acquisition step of acquiring second data including information on a second discharge path that represents the movement path for forming a surface layer of the three-dimensional object that is not in contact with another layer on at least one of an upper side and a lower side in a stacking direction of the layers, and that is different from the side surface portion; a third acquisition step of acquiring third data including information on a third discharge path that represents the movement path for forming an internal layer of the three-dimensional object that is located inside the side surface portion and the surface layer; A data generation method comprising: a first expansion process for expanding a first overlapping region included in the internal layer, the first overlapping region overlapping the side portion when viewed in the stacking direction, and a first adjacent layer included in the surface layer, the first adjacent layer adjacent to the first overlapping region in a layer direction perpendicular to the stacking direction.

2. 2. The data generation method according to claim 1, A data generation method in which, in the first expansion process, the first adjacent layer is expanded by generating a new second ejection path that spans the original portion of the first adjacent layer and the first added portion of the first adjacent layer that is added by the expansion.

3. 2. The data generation method according to claim 1, A data generation method in which, in the first expansion process, the first adjacent layer is expanded by expanding the line width of the movement path of the second discharge path that is adjacent to the first overlap region in the layer direction.

4. 2. The data generation method according to claim 1, A data generation method in which, in the first expansion process, the first adjacent layer is expanded by generating a first additional path in the first additional portion, which is the movement path for forming the first additional portion of the first adjacent layer that is added by expansion.

5. 5. The data generation method according to claim 4, A data generating method, wherein the line width of the first additional path is different from the line width of the movement path of the first discharge path that contacts the first additional portion in the stacking direction.

6. 5. The data generation method according to claim 4, The data generating method, wherein the first additional path, when viewed in the stacking direction, intersects with the movement path of the first discharge path that contacts the first additional portion in the stacking direction.

7. 2. The data generation method according to claim 1, the surface layer includes a top layer having no other layers in contact therewith above, and a bottom layer having no other layers in contact therewith below, A data generation method, wherein the expansion width in the layer direction of the top layer in the first expansion process and the expansion width in the layer direction of the bottom layer in the first expansion process are determined individually.

8. 8. The data generation method according to claim 1, further comprising: a fourth acquisition step of acquiring fourth data including information on a fourth discharge path that represents the movement path for forming an intermediate layer of the three-dimensional object that is located between the surface layer and the internal layer in the stacking direction.

9. The data generation method according to claim 8, further comprising: A data generation method comprising: a second expansion process for expanding a second adjacent layer included in the intermediate layer, the second adjacent layer being adjacent to the second overlap region in the layer direction, to a second overlap region in the internal layer that overlaps the side portion when viewed in the stacking direction.

10. 10. The data generation method according to claim 9, A data generation method in which, in the second expansion process, the second adjacent layer is expanded by generating a new fourth ejection path that spans the original portion of the second adjacent layer and the second added portion of the second adjacent layer that is added by the expansion.

11. 10. The data generation method according to claim 9, A data generation method in which, in the second expansion process, the second adjacent layer is expanded by expanding the line width of the movement path of the fourth discharge path that is adjacent to the second adjacent layer in the layer direction.

12. 10. The data generation method according to claim 9, A data generation method in which, in the second expansion process, the second adjacent layer is expanded by generating a second additional path in the second additional portion, which is the movement path for forming the second additional portion of the second adjacent layer that is added by expansion.

13. 10. The data generation method according to claim 9, the surface layer includes a top layer having no other layers in contact therewith above, and a bottom layer having no other layers in contact therewith below, the intermediate layer includes an upper layer located between the uppermost layer and the internal layer in the stacking direction, and a lower layer located between the lowermost layer and the internal layer in the stacking direction, A data generation method in which the expansion width in the layer direction of the upper layer in the second expansion process and the expansion width in the layer direction of the lower layer in the second expansion process are determined individually.

14. 10. The data generation method according to claim 9, the filling rate of the surface layer is higher than the filling rate of the intermediate layer, A data generation method, wherein the filling rate of the intermediate layer is higher than the filling rate of the inner layer.

Images