Laminate molding device, laminate molding method, and program

Abstract

To suppress a forming failure of a contour of a molding while suppressing a heat input failure inside the molding.SOLUTION: In a laminate molding device 1, a setting unit sets a plurality of contour paths CP and a plurality of hatching paths HP as irradiation paths LP for irradiating a power material with a beam by a beam irradiation unit. The plurality of contour paths CP are for irradiating a first part P1 equivalent to a contour 3a of a molding 3 with the beam. The plurality of hatching paths HP are for irradiating a second part P2 equivalent to an internal region surrounded by the contour 3a with the beam. The plurality of contour paths CP form a contour path overlapping region CR in which contour paths CP different from each other overlap. The plurality of hatching paths HP form a hatching path overlapping region HR in which hatching paths HP different from each other overlap. The hatching path overlapping region HR and the contour path overlapping region CR are separated from each other.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to an additive manufacturing apparatus, an additive manufacturing method, and a program. [Background technology]

[0002] There is known an additive manufacturing apparatus that manufactures a molded object from a powder material. The additive manufacturing apparatus irradiates a beam onto the powder material to heat the powder material (for example, Patent Document 1 and Patent Document 2). As a result, the powder material melts and a molded object is formed. Such an additive manufacturing apparatus is provided with a beam irradiation unit that irradiates the beam and a setting unit that sets an area to be irradiated with the beam. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2016-526098 [Patent Document 2] International Publication No. 2015 / 133138 Summary of the Invention [Problem to be solved by the invention]

[0004] In the example shown in Patent Document 1, beams are irradiated from each of a plurality of beam sources to different regions, and the powder material is heated. In this case, in order to prevent poor heat input to the powder material, the regions irradiated with beams from different beam sources are set to overlap at least in part. It is also possible to rotate a table on which the powder material is placed, and irradiate different regions with beams according to the rotation of the table. In other words, the region irradiated with the beam differs according to the rotation position of the table. In such rotational additive manufacturing, the regions irradiated with the beam at different rotation positions of the table are also set to overlap at least in part.

[0005] However, when the areas irradiated with the beam overlap, there is a concern of excessive heat input. If the amount of heat input is too large, there is a risk of the molded object having a defective shape. The more areas irradiated with the beam, the more difficult it becomes to achieve a balanced heat input by simply adjusting the irradiation intensity or irradiation time of the beam. For example, in the example shown in Patent Document 2, the area irradiated with the beam is divided into a part corresponding to the outline of the molded object and a part corresponding to the internal area surrounded by the outline. In this case, it is required to suppress the defective shape of the outline of the molded object while suppressing the defective heat input of the internal area.

[0006] The present disclosure describes an additive manufacturing apparatus, an additive manufacturing method, and a program that can suppress poor heat input inside an object while suppressing shape defects in the contour of the object. [Means for solving the problem]

[0007] An additive manufacturing apparatus according to an embodiment of the present disclosure includes a table, a beam irradiation unit, and a setting unit. The table supports a powder material and a model made of the powder material. The beam irradiation unit irradiates a beam onto the powder material arranged on the table to heat the powder material. The setting unit sets an irradiation path for irradiating the powder material with the beam by the beam irradiation unit. The setting unit sets a plurality of contour paths and a plurality of hatching paths as the irradiation paths. The plurality of contour paths irradiate a first portion corresponding to a contour portion of the model with the beam. The plurality of hatching paths irradiate a second portion corresponding to an internal region surrounded by the contour portion with the beam. The plurality of contour paths form a contour path overlapping region where different contour paths are overlapped. The plurality of hatching paths form a hatching path overlapping region where different hatching paths are overlapped. The hatching path overlapping region and the contour path overlapping region are separated from each other.

[0008] In the above-mentioned additive manufacturing device, a hatching path overlapping region and a contour path overlapping region are set. This makes it possible to suppress poor heat input. Furthermore, the hatching path overlapping region and the contour path overlapping region are separated from each other. In this case, heat in the hatching path overlapping region is unlikely to affect the contour path overlapping region. This makes it possible to suppress poor shape of the contour of the molded object.

[0009] In some embodiments, the setting unit may set a plurality of first layer contour paths and a plurality of second layer contour paths as the plurality of contour paths. The plurality of first layer contour paths are for irradiating a beam onto a first layer made of a powder material. The plurality of second layer contour paths are for irradiating a beam onto a second layer made of a powder material and laminated on the first layer. The plurality of first layer contour paths may form a first contour path overlapping region where different first layer contour paths overlap. The plurality of second layer contour paths may form a second contour path overlapping region where different second layer contour paths overlap. The first contour path overlapping region and the second contour path overlapping region may be separated from each other. In this case, heat in the first contour path overlapping region is unlikely to affect the second contour path overlapping region. This further suppresses shape defects of the contour of the molded object.

[0010] In some embodiments, the beam irradiation unit may include a first beam source and a second beam source. The first beam source irradiates a powder material arranged in a first region of the table with a beam. The second beam source irradiates a powder material arranged in a second region of the table with a beam. The first region and the second region may include a mutually overlapping portion and a mutually non-overlapping portion. The setting unit may set, as the hatching path, a first hatching path for irradiating a beam by the first beam source in the first region, and a second hatching path for irradiating a beam by the second beam source in the second region. The setting unit may set, as the contour path, a first contour path for irradiating a beam by the first beam source in the first region, and a second contour path for irradiating a beam by the second beam source in the second region. In this case, when a plurality of beam sources are used, a shape defect of the contour of the molded object can be suppressed while a heat input defect inside the molded object is suppressed.

[0011] In some embodiments, the setting unit may set the irradiation paths such that the first hatching path and the second hatching path are irradiated with the beam, and then the first contour path and the second contour path are irradiated with the beam. In this case, shape defects of the contour of the object can be further suppressed.

[0012] In some embodiments, the table may be configured to be rotatable. The beam irradiation unit may irradiate the powder material arranged in a first region of the table with the beam, and after the powder material arranged in the first region is irradiated with the beam and the table is rotated, irradiate the powder material arranged in a second region of the table with the beam. The first region and the second region may include a mutually overlapping portion and a mutually non-overlapping portion. In this case, when rotational additive manufacturing is performed, a shape defect of the contour of the modeled object can be suppressed while a heat input defect inside the modeled object is suppressed.

[0013] In some embodiments, the setting unit may set, as the hatching path, a first hatching path for irradiating the first region with the beam, and a second hatching path for irradiating the second region with the beam. The setting unit may set, as the contour path, a first contour path for irradiating the first region with the beam, and a second contour path for irradiating the second region with the beam. The irradiation paths may be set so that the beam is irradiated in the order of the first hatching path, the first contour path, the second hatching path, and the second contour path. In this case, shape defects of the contour of the modeled object may be further suppressed.

[0014] An additive manufacturing method according to an embodiment of the present disclosure includes setting an irradiation path for irradiating a powder material arranged on a table with a beam, and irradiating the irradiation path with a beam. In setting the irradiation path, a plurality of contour paths and a plurality of hatching paths are set as the irradiation paths. The plurality of contour paths are for irradiating a first portion corresponding to a contour portion of a model with a beam. The plurality of hatching paths are for irradiating a second portion corresponding to an internal region surrounded by the contour portion with a beam. The plurality of contour paths form a contour path overlapping region where different contour paths overlap. The plurality of hatching paths form a hatching path overlapping region where different hatching paths overlap. The hatching path overlapping region and the contour path overlapping region are separated from each other.

[0015] A program according to an embodiment of the present disclosure causes a computer to set an irradiation path for irradiating a powder material arranged on a table with a beam, and irradiate the irradiation path with a beam. In setting the irradiation path, a plurality of contour paths and a plurality of hatching paths are set as the irradiation paths. The plurality of contour paths are for irradiating a first portion corresponding to a contour portion of a molded object with a beam. The plurality of hatching paths are for irradiating a second portion corresponding to an internal region surrounded by the contour portion with a beam. The plurality of contour paths form a contour path overlapping region where different contour paths overlap. The plurality of hatching paths form a hatching path overlapping region where different hatching paths overlap. The hatching path overlapping region and the contour path overlapping region are separated from each other. Effect of the Invention

[0016] According to some aspects of the present disclosure, there is provided an additive manufacturing apparatus, an additive manufacturing method, and a program that can suppress poor heat input inside an object while suppressing shape defects in the contour of the object. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a cross-sectional view showing an additive manufacturing apparatus according to an embodiment. [Diagram 2] FIG. 2 is a conceptual diagram for explaining an area irradiated with a beam. [Diagram 3] FIG. 3 is a conceptual diagram showing the relationship between a contour path overlapping region and a hatching path overlapping region. [Figure 4] FIG. 4 is a conceptual diagram showing the relationship between contour path overlapping regions in the same layer as viewed from the lamination direction, as a modified example of this embodiment. [Diagram 5] FIG. 5 is a conceptual diagram showing the relationship between contour path overlapping regions in different layers as viewed from the side as a modified example of this embodiment. [Figure 6] FIG. 6 is a diagram illustrating an example of a hardware configuration of the control unit. [Figure 7]FIG. 7 is a flowchart of the additive manufacturing method. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the description of the drawings, the same elements are given the same reference numerals, and duplicated description will be omitted.

[0019] The additive manufacturing apparatus shown in FIG. 1 is a so-called 3D (three-dimensional) printer. In the following description, the additive manufacturing apparatus will be simply referred to as a "modeling apparatus 1." The modeling apparatus 1 obtains a three-dimensional object 3. The modeling apparatus 1 partially applies energy to powder material 2 arranged in layers to sinter or melt the powder material 2. The modeling apparatus 1 manufactures the three-dimensional object 3 by repeating the sintering or melting of the powder material 2 and layering.

[0020] The molded object 3 is, for example, a machine part. The molded object 3 may be another structure. The powder material 2 is, for example, a titanium-based metal powder, Inconel (registered trademark) powder, aluminum powder, stainless steel powder, or the like. The powder that is the material of the molded object 3 is not limited to metal powder. The powder may contain carbon fiber and resin, for example, CFRP (Carbon Fiber Reinforced Plastics). The powder may also contain other materials. For example, the powder may contain a conductive material that has electrical conductivity. For example, granules with a relatively large particle size may be used as the powder.

[0021] The modeling apparatus 1 includes a vacuum chamber 4, a working table 5, a lifting device 6, a powder supplying device 7, a beam irradiation unit 8, a modeling tank 10, and a control unit 18 (setting unit). The vacuum chamber 4 is a container capable of creating a vacuum (low pressure) state inside. A vacuum pump (not shown) is connected to the vacuum chamber 4. The working table 5 has, for example, a plate-like shape. The working table 5 has, for example, a circular shape in a plan view. The shape of the working table 5 is not limited to a circular shape. The working table 5 may have a rectangular shape. The working table 5 may also have another shape.

[0022] A substrate 15 is placed on the working table 5. A powder material 2, which is a material for the model 3, is placed on the substrate 15. The powder material 2 on the substrate 15 is placed, for example, in layers in a number of batches. The configuration of the substrate 15 will be described later.

[0023] The working table 5 and the substrate 15 are disposed in the modeling tank 10 within the vacuum chamber 4. In the modeling tank 10, the working table 5 is movable in the Z direction (up and down direction). The working table 5 descends sequentially according to the number of layers of the powder material 2. The side wall 10a of the modeling tank 10 guides the movement of the working table 5. The shape of the side wall 10a corresponds to the outer shape of the working table 5. For example, when the shape of the working table 5 is a disk, the shape of the area surrounded by the side wall 10a is cylindrical. Also, when the shape of the working table 5 is rectangular, the shape of the area surrounded by the side wall 10a is a square tube. The side wall 10a and the working table 5 of the modeling tank 10 form a storage section that stores the powder material 2 and the modeled object 3. The working table 5 may constitute the bottom of the modeling tank 10.

[0024] The lifting device 6 lifts and lowers the working table 5. When the lifting device 6 lifts and lowers the working table 5, the substrate 15 on the working table 5, the powder material 2 on the substrate 15, and the molded object 3 are lifted and lowered. The lifting device 6 includes, for example, a rack-and-pinion type driving mechanism. With these mechanisms, the lifting device 6 moves the working table 5 in the Z direction. The lifting device 6 includes a vertical member 6a (rack) and a driving source 6b. The vertical member 6a is a rod-shaped member that is connected to the back surface of the working table 5 and extends downward. The driving source 6b drives the vertical member 6a. For example, an electric motor may be used as the driving source 6b. A pinion is provided on the output shaft of the electric motor. A tooth profile that meshes with the pinion is provided on the side of the vertical member 6a. When the electric motor is driven, the pinion rotates. Power is transmitted by the rotation of the pinion. As a result, the vertical member 6a moves in the vertical direction. When the rotation of the electric motor is stopped, the vertical member 6a is positioned. As a result, the position of the work table 5 in the Z direction is determined, and the position of the work table 5 is maintained. The lifting device 6 is not limited to a rack-and-pinion type drive mechanism. For example, the lifting device 6 may include other drive mechanisms such as a ball screw, a cylinder, etc.

[0025] The powder supplying device 7 includes a raw material tank 11. The raw material tank 11 is a storage unit that stores the powder material 2, which is the raw material. The raw material tank 11 is disposed in the vacuum chamber 4. The raw material tank 11 is disposed above the work table 5 in the Z direction. The raw material tank 11 is disposed, for example, on both sides of the irradiation area D of the electron beam by the beam irradiation unit 8 in the X direction intersecting with the Z direction. An outlet is provided at the bottom of the raw material tank 11. The outlet is continuous in, for example, the Y direction. The Y direction is a direction intersecting the X direction and the Z direction.

[0026] Below the raw material tank 11, an extension plate 12 is provided, which extends laterally from the upper end of the side wall 10a of the modeling tank 10. The extension plate 12 forms a plane that intersects with the Z direction around the work table 5.

[0027] The powder supplying device 7 includes a powder coating mechanism 13 that levels the powder material 2. The powder coating mechanism 13 includes a recoater 13a. The recoater 13a is movable in the X direction above the work table 5 and the extension plate 12. The recoater 13a scrapes the powder material 2 deposited on the extension plate 12 onto the work table 5 by this movement. Furthermore, the recoater 13a levels the surface 2a (upper surface) of the top layer of the stack of powder material 2 on the work table 5 by this movement. Hereinafter, the "stack of powder material 2" is referred to as powder bed A. The recoater 13a abuts against the surface 2a of the powder bed A to make the height uniform. The shape of the recoater 13a is, for example, plate-like. The recoater 13a has a predetermined width in the Y direction. The length of the powder coating mechanism in the Y direction corresponds to, for example, the total length of the work table 5 in the Y direction. The powder coating mechanism 13 may be configured to include a roller, a rod-shaped member, a brush part, or the like, instead of the plate-shaped recoater 13a.

[0028] Powder coating mechanism 13 may include, for example, a rack-and-pinion driving mechanism as a mechanism for moving recoater 13a. Powder coating mechanism 13 may include a guide rail, an endless belt, a ball screw, an electric motor, a cylinder, etc.

[0029] The beam irradiation unit 8 includes, for example, at least one beam source. In the example shown in this embodiment, the beam irradiation unit 8 includes, for example, a plurality of beam sources. Each of the first beam source 8a and the second beam source 8b is, for example, a beam irradiation device that irradiates an energy beam. The beam irradiation device irradiates, for example, an electron beam. For example, the beam irradiation device may include an electron gun that irradiates an electron beam. As a modified example of this embodiment, the beam irradiation device may irradiate laser light. Hereinafter, the energy beam irradiated by the beam irradiation unit 8 is simply referred to as a "beam".

[0030] In FIG. 1, an irradiation region D through which the emitted beam passes is indicated by a two-dot chain line. The beam emitted from the electron gun is irradiated into a vacuum chamber 4. The beam heats the powder material 2. A beam irradiation unit 8 imparts energy to the powder material 2. As a result, the powder material 2 is heated and melts or sinters. The beam irradiation unit 8 solidifies the powder material 2 in the powder bed A.

[0031] The multiple beam sources of the beam irradiation unit 8 each irradiate a beam to a different region of the work table 5. The regions irradiated with beams by the multiple beam sources of the beam irradiation unit 8 include overlapping portions and non-overlapping portions. The first beam source 8a irradiates a beam to the powder material 2 arranged in the first region R1 of the work table 5. The second beam source 8b irradiates a beam to the powder material 2 arranged in the second region R2 of the work table 5. The first region R1 and the second region R2 include overlapping portions and non-overlapping portions.

[0032] The beam irradiation unit 8 may include, for example, a coil device that controls the irradiation of the beam. In this case, the beam is an electron beam. The coil device includes, for example, an aberration coil, a focus coil, and a deflection coil. The aberration coil is installed around the beam emitted from the electron gun and converges the beam. The focus coil is installed around the beam emitted from the electron gun and corrects the deviation of the focus position of the beam. The deflection coil is installed around the beam emitted from the electron gun and adjusts the irradiation position of the beam. The deflection coil performs electromagnetic beam deflection. According to the electromagnetic beam deflection, the scanning speed during the irradiation of the beam is faster than that of mechanical beam deflection. The electron gun and the coil unit are arranged at the top of the vacuum chamber 4. The beam emitted from the electron gun is converged by the coil unit, the focus position is corrected, the scanning speed is controlled, and the beam reaches the irradiation position of the powder material 2.

[0033] The control unit 18, which is a control unit, controls the operation of the entire modeling apparatus 1. The control unit 18 is a computer including hardware such as a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory), and software such as a program stored in the ROM. The control unit 18 includes an input signal circuit, an output signal circuit, a power supply circuit, etc. The control unit 18 includes a calculation unit and a memory. The control unit 18 is electrically connected to the beam irradiation unit 8, the powder supplying device 7, and the lifting device 6. The control unit 18 can generate various command signals. The memory can store data necessary for various controls.

[0034] The control unit 18 transmits a command signal to the beam irradiation unit 8 to control the timing and position of the beam irradiation (irradiation control). The control unit 18 controls the beam irradiation when melting the powder material 2. The control unit 18 transmits a command signal to the powder supplying device 7 to control the timing and amount of powder material 2 supplied. The control unit 18 may transmit a command signal to the powder coating mechanism 13 to control the operation timing of the recoater 13a, etc. The control unit 18 controls the lifting device 6, the powder supplying device 7, and the beam irradiation unit 8 to repeat the sintering or melting and lamination of the powder material 2.

[0035] Next, the beam irradiation by the control unit 18 will be described in detail with reference to Fig. 2 to Fig. 5. Fig. 2 is a conceptual diagram for explaining an area to be irradiated with the beam. The control unit 18 includes a setting unit 21.

[0036] The setting unit 21 sets an irradiation path LP for irradiating the powder material 2 with a beam by the beam irradiation unit 8. The irradiation path includes a contour path and a hatching path. The contour path is an irradiation path for irradiating a portion corresponding to the contour of the object with a beam. The hatching path is an irradiation path for irradiating a portion corresponding to the internal region surrounded by the contour. In this specification, an "irradiation path" is a continuous irradiation path on the irradiated surface of the irradiation target to which the beam is irradiated, and corresponds to continuous irradiation positions on the irradiated surface of the irradiation target. For example, even if the beam is a pulse wave, if the irradiation spots of the beam irradiated from one beam source are continuous on the irradiated surface of the irradiation target, it is considered to be one irradiation path.

[0037] The setting unit 21 sets a plurality of contour paths CP and a plurality of hatching paths HP as the irradiation paths LP. Each of the plurality of contour paths CP is an irradiation path LP that irradiates a first portion P1 corresponding to the contour portion of the object 3 with a beam. Each of the plurality of hatching paths HP is an irradiation path LP that irradiates a second portion P2 corresponding to an internal region surrounded by the contour portion of the object 3 with a beam. In the example shown in this embodiment, the first portion P1 surrounds the second portion P2.

[0038] As shown in FIG. 2, the multiple contour paths CP form a contour path overlapping region CR where different contour paths CP overlap. Here, "different contour paths CP" means contour paths CP that perform discontinuous beam irradiation at different times, or contour paths CP from different beam sources. "Discontinuous beam irradiation" means that a beam is irradiated once at a predetermined location, then a portion different from the predetermined location is irradiated with the beam, and then the predetermined location is irradiated with the beam again. Therefore, discontinuous beam irradiation on the contour path overlapping region CR means that a beam is irradiated once at the contour path overlapping region CR, then a portion different from the contour path overlapping region CR is irradiated with the beam, and then the contour path overlapping region CR is irradiated with the beam again. The first portion P1 includes the contour path overlapping region CR. The multiple hatching paths HP include a hatching path overlapping region HR where different hatching paths HP overlap. The second portion P2 includes the hatching path overlapping region HR. The hatching path overlapping region HR and the contour path overlapping region CR are spaced apart from each other.

[0039] For example, the multiple contour paths CP include a first contour path CP1 that irradiates a beam from a first beam source 8a and a second contour path CP2 that irradiates a beam from a second beam source 8b. The first contour path CP1 and the second contour path CP2 overlap each other to form a contour path overlap region CR.

[0040] The hatching paths HP include a first hatching path HP1 that is irradiated with a beam by a first beam source 8a and a second hatching path HP2 that is irradiated with a beam by a second beam source 8b. The first hatching path HP1 and the second hatching path HP2 overlap each other to form a hatching path overlap region HR.

[0041] The setting unit 21 sets the first contour path CP1, which is irradiated with a beam by the first beam source 8a, in the first region R1 as the contour path CP, and sets the second contour path CP2, which is irradiated with a beam by the second beam source 8b, in the second region R2 as the hatching path HP. The setting unit 21 sets the first hatching path HP1, which is irradiated with a beam by the first beam source 8a, in the first region R1 as the hatching path HP, and sets the second hatching path HP2, which is irradiated with a beam by the second beam source 8b, in the second region R2 as the hatching path HP. The setting unit 21 sets the irradiation path LP so that, for example, the first hatching path HP1 and the second hatching path HP2 are irradiated with a beam, and then the first contour path CP1 and the second contour path CP2 are irradiated with a beam.

[0042] For example, the setting unit 21 sets a plurality of contour paths CP and a plurality of hatching paths HP in the same layer among the plurality of layers arranged on the working table 5. A contour path overlapping region CR and a hatching path overlapping region HR are formed in the same layer.

[0043] FIG. 3 is a conceptual diagram showing the relationship between the contour path overlapping region CR and the hatching path overlapping region HR. The contour path overlapping region CR and the hatching path overlapping region HR are set to satisfy the following formula (1): X=h / 2+c / 2+a. "X" is the shift amount between the contour path overlapping region CR and the hatching path overlapping region HR at the boundary between the first portion P1 and the second portion P2. "h" is the width of the hatching path overlapping region HR. "c" is the width of the contour path overlapping region CR. "a" is the distance between the contour path overlapping region CR and the hatching path overlapping region HR at the boundary between the first portion P1 and the second portion P2. For example, "a" is greater than zero. "h" and "c" are, for example, greater than or equal to the irradiation spot diameters of the first beam source 8a and the second beam source 8b.

[0044] As a modified example of this embodiment, a plurality of hatching path overlapping regions HR may be formed in the same layer. In this case, for example, all of the hatching path overlapping regions HR may be set to be separated from the contour path overlapping region CR. For example, the setting unit 21 may set three or more hatching paths HP in the same layer. In this case, the three or more hatching paths HP may be connected to form one continuous region.

[0045] As a modified example of this embodiment, a plurality of contour path overlapping regions CR may be formed in the same layer. In this case, for example, all of the contour path overlapping regions CR may be set to be separated from the hatching path overlapping region HR. For example, the setting unit 21 may set three or more contour paths CP in the same layer. In this case, three or more contour paths CP may be connected to form one continuous region. For example, three or more contour paths CP may be arranged on one virtual line LN in the same layer. Three or more contour paths CP may be connected on one virtual line LN.

[0046] Next, a modified example of this embodiment will be described with reference to Fig. 4. Fig. 4 is a conceptual diagram showing the relationship between contour path overlapping regions in the same layer as viewed from the lamination direction, as a modified example of this embodiment.

[0047] As shown in FIG. 4, the setting unit 21 sets a plurality of contour paths CP in the first portion P1 of the same layer so as to be arranged on a plurality of virtual lines LN. In the example shown in FIG. 4, the plurality of virtual lines LN include a virtual line LN1, a virtual line LN2, and a virtual line LN3. The plurality of virtual lines LN1, LN2, and LN3 surround the same first hatching path HP1 and second hatching path HP2, respectively. The virtual line LN1 is closest to the first hatching path HP1 and the second hatching path HP2 in the virtual lines LN1, LN2, and LN3, extends along the edges of the first hatching path HP1 and the second hatching path HP2, and is located between the virtual line LN2 and the first hatching path HP1 and the second hatching path HP2. The virtual line LN2 extends along the virtual line LN1 and is located between the virtual line LN3 and the virtual line LN1. The imaginary line LN3 extends along the imaginary line LN2.

[0048] 4, the multiple contour paths CP include multiple first contour paths CP11, CP12, CP13 that irradiate a beam by the first beam source 8a, and multiple second contour paths CP21, CP22, CP23 that irradiate a beam by the second beam source 8b. The setting unit 21 sets the first contour paths CP11, CP12, CP13 that irradiate a beam by the first beam source 8a in a first region R1 as the contour paths CP, and sets the second contour paths CP21, CP22, CP23 that irradiate a beam by the second beam source 8b in a second region R2.

[0049] The first contour path CP11 and the second contour path CP21 are arranged on a virtual line LN1. The first contour path CP11 and the second contour path CP21 overlap each other to form a contour path overlap region CR1 as the contour path overlap region CR. The first contour path CP12 and the second contour path CP22 are arranged on a virtual line LN2. The first contour path CP12 and the second contour path CP22 overlap each other to form a contour path overlap region CR2 as the contour path overlap region CR. The first contour path CP13 and the second contour path CP23 are arranged on a virtual line LN3. The first contour path CP13 and the second contour path CP23 overlap each other to form a contour path overlap region CR3 as the contour path overlap region CR.

[0050] The contour path overlapping region CR1 and the contour path overlapping region CR2 are separated from each other. The contour path overlapping region CR1 and the contour path overlapping region CR2 are perpendicular to the stacking direction and are shifted in a direction along the edges of the first hatching path HP1 and the second hatching path HP2. The contour path overlapping region CR2 and the contour path overlapping region CR3 are separated from each other. The contour path overlapping region CR2 and the contour path overlapping region CR3 are perpendicular to the stacking direction and are shifted in a direction along the edges of the first hatching path HP1 and the second hatching path HP2. In the example shown in FIG. 4, the contour path overlapping region CR1 and the contour path overlapping region CR3 are separated from each other. In this example, the contour path overlapping region CR1 and the contour path overlapping region CR3 are perpendicular to the stacking direction and are shifted in a direction along the edges of the first hatching path HP1 and the second hatching path HP2. As a further modification of this modification, the contour path overlapping region CR1 and the contour path overlapping region CR3 may overlap each other when viewed from a direction perpendicular to the stacking direction.

[0051] Next, a modified example of this embodiment will be described with reference to Fig. 5. Fig. 5 is a conceptual diagram showing the relationship between contour path overlapping regions in different layers as viewed from a direction perpendicular to the stacking direction, as a modified example of this embodiment.

[0052] In the example shown in FIG. 5, the control unit 18 irradiates a beam onto a layer of powder material 2 arranged on the work table 5, and forms a first layer L1 by sintering or melting the powder material 2 by irradiating the beam. Next, the control unit 18 forms a layer of powder material 2 on the first layer L1 after the first layer L1 is formed. The control unit 18 irradiates a beam onto the layer of powder material 2 formed on the first layer L1, and forms a second layer L2 by sintering or melting the powder material 2 by irradiating the beam. Furthermore, the control unit 18 forms a layer of powder material 2 on the second layer L2 after the second layer L2 is formed. The control unit 18 irradiates a beam onto the layer of powder material 2 formed on the second layer L2, and forms a third layer L3 by sintering or melting the powder material 2 by irradiating the beam. In the model, the first layer L1 and the second layer L2 are adjacent layers. In the model, the second layer L2 and the third layer L3 are adjacent layers.

[0053] As shown in FIG. 5, the setting unit 21 sets a plurality of contour paths CP and a plurality of hatching paths HP for each of a plurality of layers of the powder material 2 arranged on the working table 5. For example, as shown in FIG. 5, the setting unit 21 sets a plurality of first layer contour paths LCP1, a plurality of second layer contour paths LCP2, and a plurality of third layer contour paths LCP3 as the contour paths CP. The plurality of first layer contour paths LCP1 are irradiation paths LP that irradiate the first portion P1 of the layer of the powder material 2 with a beam in forming the first layer L1. The plurality of second layer contour paths LCP2 are irradiation paths LP that irradiate the first portion P1 of the layer of the powder material 2 with a beam in forming the second layer L2. The plurality of third layer contour paths LCP3 are irradiation paths LP that irradiate the first portion P1 of the layer of the powder material 2 with a beam in forming the third layer L3.

[0054] The multiple first layer contour paths LCP1 form a first contour path overlapping region CR11 where the mutually different first layer contour paths LCP1 overlap. The multiple second layer contour paths LCP2 form a second contour path overlapping region CR12 where the mutually different second layer contour paths LCP2 overlap. The multiple third layer contour paths LCP3 form a third contour path overlapping region CR13 where the mutually different third layer contour paths LCP3 overlap.

[0055] The first contour path overlapping region CR11 and the second contour path overlapping region CR12 are separated from each other. The first contour path overlapping region CR11 and the second contour path overlapping region CR12 are perpendicular to the stacking direction and are shifted in a direction along the edges of the first hatching path HP1 and the second hatching path HP2. For example, the first contour path overlapping region CR11 and the second contour path overlapping region CR12 do not overlap when viewed from the stacking direction. The second contour path overlapping region CR12 and the third contour path overlapping region CR13 are separated from each other. The second contour path overlapping region CR12 and the third contour path overlapping region CR13 are perpendicular to the stacking direction and are shifted in a direction along the edges of the first hatching path HP1 and the second hatching path HP2. For example, the second contour path overlapping region CR12 and the third contour path overlapping region CR13 do not overlap when viewed from the stacking direction. For example, the first contour path overlapping region CR11 and the third contour path overlapping region CR13 do not overlap when viewed from the stacking direction. As a further modification of this modification, the first contour path overlapping region CR11 and the third contour path overlapping region CR13 may overlap each other when viewed from the stacking direction.

[0056] As yet another modification of this embodiment, the modeling apparatus 1 may perform rotational additive manufacturing. In this case, the working table 5 rotates, and the beam is irradiated to different areas in accordance with the rotation of the working table 5. In other words, the area irradiated with the beam is switched by the rotation of the working table 5. For example, the area irradiated with the beam is switched from the first area R1 to the second area R2 by the rotation of the working table 5. In this case as well, the first area R1 and the second area R2 include overlapping areas and non-overlapping areas. In this modification, the beam irradiation unit 8 may have one beam source.

[0057] In this modification, the working table 5 is configured to be rotatable. The molding apparatus 1 may further include a rotation drive device that rotates the working table 5. For example, the rotation drive device is driven in response to a command signal from the control unit 18.

[0058] In this modified example, the beam irradiation unit 8 irradiates, for example, the powder material 2 arranged in the first region R1 of the working table 5 with a beam. After the powder material 2 arranged in the first region R1 is irradiated with a beam and the working table 5 is rotated, the beam irradiation unit 8 irradiates the powder material 2 arranged in the second region R2 of the working table 5 with a beam. The setting unit 21 sets a plurality of contour paths CP at each of a plurality of rotation positions of the working table 5. The setting unit 21 sets a plurality of hatching paths HP at each of a plurality of rotation positions of the working table 5.

[0059] The setting unit 21 sets a first contour path CP1 for irradiating the beam to a first region R1 as a contour path CP, and sets a second contour path CP2 for irradiating the beam to a second region R2 as a hatching path HP. The setting unit 21 sets a first hatching path HP1 for irradiating the beam to a first region R1 as a hatching path HP, and sets a second hatching path HP2 for irradiating the beam to a second region R2 as a hatching path HP. The setting unit 21 sets the irradiation path LP so that the beam is irradiated in the order of, for example, the first hatching path HP1, the first contour path CP1, the second hatching path HP2, and the second contour path CP2.

[0060] Next, the hardware configuration of the control unit 18 will be described with reference to Fig. 6. Fig. 6 is a diagram showing an example of the hardware configuration of the control unit 18. As shown in Fig. 6, the control unit 18 includes one or more computers. The computers execute an additive manufacturing program PG. The additive manufacturing program PG causes the computers to execute an additive manufacturing method.

[0061] The control unit 18 has a CPU (Central Processing Unit) 81, which is a processor, a main memory unit 82, an auxiliary memory unit 83, a communication control unit 84, an input device 85, and an output device 86. The control unit 18 is configured by one or more computers configured by these hardware units and software such as programs.

[0062] When the control unit 18 is composed of multiple computers, these computers may be connected locally or via a communication network such as the Internet or an intranet. This connection logically constitutes one control unit 18.

[0063] The CPU 81 executes an operating system, application programs, etc. The main memory 82 is composed of a ROM (Read Only Memory) and a RAM (Random Access Memory). The auxiliary memory 83 is a storage medium composed of a hard disk, a flash memory, etc. The auxiliary memory 83 generally stores a larger amount of data than the main memory 82. The communication control unit 84 is composed of a network card or a wireless communication module. The input device 85 is composed of a keyboard, a mouse, a touch panel, a microphone for voice input, etc. The output device 86 is composed of a display, a printer, etc.

[0064] The auxiliary storage unit 83 stores in advance the additive manufacturing program PG and data necessary for processing. The additive manufacturing program PG causes the computer to execute each functional element of the control unit 18. For example, the additive manufacturing program PG is read by the CPU 81 or the main storage unit 82, and causes at least one of the CPU 81, the main storage unit 82, the auxiliary storage unit 83, the communication control unit 84, the input device 85, and the output device 86 to operate. For example, the additive manufacturing program PG reads and writes data in the main storage unit 82 and the auxiliary storage unit 83.

[0065] The additive manufacturing program PG may be provided in a state in which it is recorded on a tangible recording medium such as a CD-ROM, a DVD-ROM, a semiconductor memory, etc. The additive manufacturing program PG may be provided as a data signal via a communication network.

[0066] Next, the additive manufacturing method will be described with reference to Fig. 7. Fig. 7 is a flowchart of the additive manufacturing method.

[0067] First, the working table 5 is prepared (step S11). Next, an irradiation path is set (step S12). For example, the setting unit 21 of the control unit 18 sets the irradiation path. The setting unit 21 acquires and sets a pre-stored irradiation path. The setting unit 21 acquires an irradiation path corresponding to the model 3. The setting unit 21 may set an irradiation path corresponding to each layer for each layer. The setting unit 21 may calculate the irradiation path based on information on the model 3, information on the working table 5, etc.

[0068] Next, the powder material 2 is applied (step S13). For example, the powder application mechanism 13 applies the powder material 2 onto the work table 5.

[0069] Next, the beam is irradiated (step S14). Based on the irradiation path set in step S12, the beam irradiating unit 8 irradiates the powder material 2 arranged on the working table 5 with the beam.

[0070] For example, when multiple beam sources are used, the beam irradiation unit 8 irradiates multiple hatching paths HP with beams, and then irradiates multiple contour paths CP with beams. The irradiation of the first hatching path HP1 and the second hatching path HP2 with beams may be performed simultaneously or sequentially. The irradiation of the first contour path CP1 and the second contour path CP2 with beams may be performed simultaneously or sequentially.

[0071] When the modeling apparatus 1 performs rotational additive manufacturing, the beam irradiation unit 8 first irradiates a hatching path HP set in the first region R1 with a beam, and then irradiates a contour path CP set in the first region R1 with the beam. When irradiation of the first region R1 with the beam is completed, the work table 5 is rotated. Next, the beam irradiation unit 8 irradiates a hatching path HP set in the second region R2 with the beam, and then irradiates a contour path CP set in the second region R2 with the beam.

[0072] Next, it is determined whether or not to end the additive manufacturing (step S15). If it is determined that the additive manufacturing is to be ended (YES in step S15), the series of processes is ended. If it is determined that the additive manufacturing is not to be ended (NO in step S15), the process returns to step S13.

[0073] Although the additive manufacturing method has been described above, the order of the processes is not limited to this. In addition, other processes may be executed between each process.

[0074] Next, the effects achieved by the molding apparatus 1 of this embodiment will be described.

[0075] In the layered manufacturing apparatus 1, a hatching path overlapping region HR and a contour path overlapping region CR are set. This prevents poor heat input between different irradiation paths. The hatching path overlapping region HR and the contour path overlapping region CR are separated from each other. In this case, the heat in the hatching path overlapping region HR is unlikely to affect the contour path overlapping region CR. This prevents poor shape of the contour portion 3a of the object 3. For example, poor surface roughness of the surface of the object 3 can also be improved.

[0076] The setting unit 21 sets a plurality of first layer contour paths LCP1 and a plurality of second layer contour paths LCP2 as the plurality of contour paths CP. The plurality of first layer contour paths LCP1 form a first contour path overlapping region CR11 where the first layer contour paths LCP1 different from each other overlap. The plurality of second layer contour paths LCP2 form a second contour path overlapping region CR12 where the second layer contour paths LCP2 different from each other overlap. The first contour path overlapping region CR11 and the second contour path overlapping region CR12 are separated from each other. In this case, the heat in the first contour path overlapping region CR11 is unlikely to affect the second contour path overlapping region CR12. This further suppresses the shape defect of the contour portion 3a of the shaped object 3.

[0077] In the example shown in this embodiment, the beam irradiation unit 8 includes a first beam source 8a and a second beam source 8b. The first beam source 8a irradiates a beam onto the powder material 2 arranged in the first region R1 of the work table 5. The second beam source 8b irradiates a beam onto the powder material 2 arranged in the second region R2 of the work table 5. The first region R1 and the second region R2 include overlapping portions and non-overlapping portions. The setting unit 21 sets, as the hatching path HP, a first hatching path HP1 irradiated with a beam by the first beam source 8a in the first region R1, and sets a second hatching path HP2 irradiated with a beam by the second beam source 8b in the second region R2. The setting unit 21 sets, as the contour path CP, a first contour path CP1 irradiated with a beam by the first beam source 8a in the first region R1, and sets a second contour path CP2 irradiated with a beam by the second beam source 8b in the second region R2. According to this configuration, even when a plurality of beam sources are used, it is possible to suppress poor heat input into the interior of the model 3 and to suppress shape defects in the contour of the model.

[0078] The setting unit 21 may set the irradiation path LP so that the first hatching path HP1 and the second hatching path HP2 are irradiated with the beam, and then the first contour path CP1 and the second contour path CP2 are irradiated with the beam. In this case, shape defects of the contour portion 3a of the object 3 can be further suppressed.

[0079] In a modified example of this embodiment, the working table 5 may be configured to be rotatable. The beam irradiation unit 8 may irradiate the powder material 2 arranged in the first region R1 of the working table 5 with a beam, and after the powder material 2 arranged in the first region R1 is irradiated with the beam and the working table 5 is rotated, the beam irradiation unit 8 may irradiate the powder material 2 arranged in the second region R2 of the working table 5 with the beam. The first region R1 and the second region R2 may include a mutually overlapping portion and a mutually non-overlapping portion. With this configuration, even when rotational additive manufacturing is performed, poor heat input inside the model 3 can be suppressed, and a shape defect of the contour of the model can be suppressed.

[0080] The setting unit 21 may set, as the hatching path HP, a first hatching path HP1 for irradiating the first region R1 with the beam, and a second hatching path HP2 for irradiating the second region R2 with the beam. The setting unit 21 may set, as the contour path CP, a first contour path CP1 for irradiating the first region R1 with the beam, and a second contour path CP2 for irradiating the second region R2 with the beam. The irradiation path LP may be set so that the beam is irradiated in the order of the first hatching path HP1, the first contour path CP1, the second hatching path HP2, and the second contour path CP2. In this case, shape defects of the contour portion 3a of the shaped object 3 can be further suppressed.

[0081] The present disclosure is not limited to the above-described embodiment. The specific aspects of the additive manufacturing apparatus, the additive manufacturing method, and the program of the present disclosure may be modified as appropriate without departing from the spirit of the claims.

[0082] For example, a configuration using multiple beam sources and a configuration of rotational additive manufacturing may be combined. In this case, for example, after irradiating a first region with beams using multiple beam sources, the work table 5 may be rotated and a second region may be irradiated with beams using multiple beam sources.

[0083] The following is a summary of the present disclosure. [1] A table for supporting a powder material and a model made from the powder material; a beam irradiation unit that irradiates the powder material placed on the table with a beam to heat the powder material; A setting unit that sets an irradiation path for irradiating the powder material with the beam by the beam irradiation unit, the setting unit sets, as the irradiation path, a plurality of contour paths for irradiating a first portion corresponding to a contour portion of the object with the beam, and a plurality of hatching paths for irradiating a second portion corresponding to an internal region surrounded by the contour portions with the beam, the plurality of contour paths form a contour path overlapping region in which the contour paths different from each other overlap each other, the plurality of hatching paths form hatching path overlapping regions in which the hatching paths different from one another overlap, An additive manufacturing apparatus, wherein the hatching path overlapping region and the contour path overlapping region are separated from each other. [2] The setting unit sets, as the plurality of contour paths, a plurality of first layer contour paths for irradiating a first layer made of the powder material with the beam, and a plurality of second layer contour paths for irradiating a second layer that is stacked on the first layer and is also made of the powder material with the beam, the plurality of first layer contour paths form a first contour path overlapping region in which the first layer contour paths different from each other overlap each other, the plurality of second layer contour paths form second contour path overlapping regions in which the second layer contour paths different from one another overlap, The additive manufacturing apparatus according to [1], wherein the first contour path overlapping region and the second contour path overlapping region are separated from each other. [3] The beam irradiation unit includes a first beam source that irradiates the powder material arranged in a first region of the table with the beam, and a second beam source that irradiates the powder material arranged in a second region of the table with the beam; The first region and the second region include a mutually overlapping portion and a mutually non-overlapping portion, The setting unit is As the hatching paths, a first hatching path for irradiating the beam from the first beam source is set in the first region, and a second hatching path for irradiating the beam from the second beam source is set in the second region; The additive manufacturing apparatus of [1] or [2], wherein as the contour paths, a first contour path for irradiating the beam by the first beam source is set in the first region, and a second contour path for irradiating the beam by the second beam source is set in the second region. [4] The setting unit sets the irradiation path so that the beam is irradiated to the first contour path and the second contour path after the beam is irradiated to the first hatching path and the second hatching path. [5] The table is configured to be rotatable; the beam irradiation unit irradiates the powder material arranged in a first region of the table with the beam, and after the powder material arranged in the first region is irradiated with the beam and the table is rotated, irradiates the powder material arranged in a second region of the table with the beam; The additive manufacturing apparatus according to [1] or [2], wherein the first region and the second region include overlapping portions and non-overlapping portions. [6] The setting unit, As the hatching paths, a first hatching path for irradiating the first region with the beam is set, and a second hatching path for irradiating the second region with the beam is set; As the contour path, a first contour path for irradiating the first region with the beam is set, and a second contour path for irradiating the second region with the beam is set; The additive manufacturing apparatus described in [5], wherein the irradiation paths are set so that the beam is irradiated in the order of the first hatching path, the first contour path, the second hatching path, and the second contour path. [7] Setting an irradiation path for irradiating a powder material placed on a table with a beam; and irradiating the illumination path with the beam; In the setting of the irradiation paths, a plurality of contour paths for irradiating a first portion corresponding to a contour of a model with the beam, and a plurality of hatching paths for irradiating a second portion corresponding to an internal region surrounded by the contour are set as the irradiation paths, the first portion includes a contour path overlapping region in which different contour paths among the plurality of contour paths overlap, the second portion includes a hatching path overlapping region in which different hatching paths among the plurality of hatching paths overlap, An additive manufacturing method, wherein the hatching path overlapping region and the contour path overlapping region are separated from each other. [8] Setting an irradiation path for irradiating a powder material placed on a table with a beam; irradiating the illumination path with the beam; In the setting of the irradiation paths, a plurality of contour paths for irradiating a first portion corresponding to a contour of an object with the beam, and a plurality of hatching paths for irradiating a second portion corresponding to an internal region surrounded by the contour are set as the irradiation paths, the first portion includes a contour path overlapping region in which different contour paths among the plurality of contour paths overlap, the second portion includes a hatching path overlapping region in which different hatching paths among the plurality of hatching paths overlap, The hatching path overlapping region and the contour path overlapping region are spaced apart from each other. [Explanation of symbols]

[0084] 1 Additive manufacturing equipment 2 Powder material 3 Sculptures 5. Work Table 8 Beam irradiation unit 18 Control Unit 21 Setting section CP Contour Path CP1 First contour pass CP2 2nd contour pass CR Contour Path Overlap Area CR11 First contour path overlap area CR12 Second contour path overlap area HP Hatch Path HP1 1st hatching path HP2 2nd hatching path HR Hatch Path Overlap Area L1 1st layer L2 2nd layer LCP1 1st layer contour pass LCP2 2nd layer contour path LP Irradiation Path P1 Part 1 P2 2nd part R1 1st area R2 2nd area

Claims

1. a table for supporting a powder material and a model formed from the powder material; a beam irradiation unit that irradiates the powder material placed on the table with a beam to heat the powder material; A setting unit that sets an irradiation path for irradiating the powder material with the beam by the beam irradiation unit, the setting unit sets, as the irradiation path, a plurality of contour paths for irradiating a first portion corresponding to a contour portion of the object with the beam, and a plurality of hatching paths for irradiating a second portion corresponding to an internal region surrounded by the contour portion with the beam, the plurality of contour paths form a contour path overlapping region in which the contour paths different from each other overlap each other, the plurality of hatching paths form hatching path overlapping regions in which the hatching paths different from one another overlap, An additive manufacturing apparatus, wherein the hatching path overlapping region and the contour path overlapping region are separated from each other.

2. the setting unit sets, as the plurality of contour paths, a plurality of first layer contour paths for irradiating a first layer made of the powder material with the beam, and a plurality of second layer contour paths for irradiating a second layer that is stacked on the first layer and is made of the powder material with the beam, the plurality of first layer contour paths form a first contour path overlapping region in which the first layer contour paths different from each other are overlapped, the plurality of second layer contour paths form second contour path overlapping regions in which the second layer contour paths different from one another overlap, The additive manufacturing apparatus according to claim 1 , wherein the first contour path overlapping region and the second contour path overlapping region are spaced apart from each other.

3. The beam irradiation unit includes a first beam source that irradiates the powder material arranged in a first region of the table with the beam, and a second beam source that irradiates the powder material arranged in a second region of the table with the beam. The first region and the second region include a mutually overlapping portion and a mutually non-overlapping portion, The setting unit is As the hatching paths, a first hatching path for irradiating the beam from the first beam source is set in the first region, and a second hatching path for irradiating the beam from the second beam source is set in the second region; The additive manufacturing apparatus according to claim 1 or 2, wherein as the contour path, a first contour path for irradiating the beam by the first beam source is set in the first region, and a second contour path for irradiating the beam by the second beam source is set in the second region.

4. The additive manufacturing apparatus according to claim 3 , wherein the setting unit sets the irradiation path such that the beam is irradiated to the first hatching path and the second hatching path, and then the beam is irradiated to the first contour path and the second contour path.

5. The table is configured to be rotatable, the beam irradiation unit irradiates the powder material arranged in a first region of the table with the beam, and after the powder material arranged in the first region is irradiated with the beam and the table is rotated, irradiates the powder material arranged in a second region of the table with the beam; The additive manufacturing apparatus according to claim 1 , wherein the first region and the second region include a portion where they overlap with each other and a portion where they do not overlap with each other.

6. The setting unit is As the hatching paths, a first hatching path for irradiating the first region with the beam is set, and a second hatching path for irradiating the second region with the beam is set; As the contour path, a first contour path for irradiating the first region with the beam is set, and a second contour path for irradiating the second region with the beam is set; The additive manufacturing apparatus according to claim 5 , wherein the irradiation paths are set such that the beam is irradiated in the order of the first hatching path, the first contour path, the second hatching path, and the second contour path.

7. Setting an irradiation path for irradiating a powder material placed on a table with a beam; and irradiating the illumination path with the beam; In the setting of the irradiation paths, a plurality of contour paths for irradiating a first portion corresponding to a contour of a model with the beam, and a plurality of hatching paths for irradiating a second portion corresponding to an internal region surrounded by the contour are set as the irradiation paths, the first portion includes a contour path overlapping region in which different contour paths among the plurality of contour paths overlap, the second portion includes a hatching path overlapping region in which different hatching paths among the plurality of hatching paths overlap, An additive manufacturing method, wherein the hatching path overlapping region and the contour path overlapping region are separated from each other.

8. Setting an irradiation path for irradiating a beam onto a powder material disposed on a table; irradiating the illumination path with the beam; In the setting of the irradiation paths, a plurality of contour paths for irradiating a first portion corresponding to a contour of a model with the beam, and a plurality of hatching paths for irradiating a second portion corresponding to an internal region surrounded by the contour are set as the irradiation paths, the first portion includes a contour path overlapping region in which different contour paths among the plurality of contour paths overlap, the second portion includes a hatching path overlapping region in which different hatching paths among the plurality of hatching paths overlap, The hatching path overlapping region and the contour path overlapping region are spaced apart from each other.

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