Additive manufacturing method and additive manufacturing apparatus

Abstract

To improve accuracy and productivity in additive manufacturing.SOLUTION: The additive manufacturing method includes: generating a plurality of beams b1 and b2; solidifying a raw material powder of a powder bed 19 by scanning the plurality of beams b1 and b2 over the powder bed 19 with a common scanner 4; and adjusting, in coordination with the scanning of the plurality of beams b1 and b2, a direction S1 in which the plurality of beams b1 and b2 are aligned at an upstream side of the scanner 4 to adjust, on the powder bed 19, a direction S2 in which a plurality of irradiation points p1 and p2 of the plurality of beams b1 and b2 are aligned.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The technology disclosed herein relates to additive manufacturing methods and apparatus. [Background technology]

[0002] Additive manufacturing techniques for producing three-dimensional objects have been known for some time. For example, Patent Document 1 discloses a technique in which a beam is irradiated onto a plane to be built from an irradiation head, and raw material powder on the plane to be built is solidified. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-072993 Summary of the Invention [Problem to be solved by the invention]

[0004] The additive manufacturing technology mentioned above allows for flexible production of minute structures. However, because minute structures are produced little by little, improvements in productivity are required. Furthermore, because it involves minute manufacturing, high precision is also required.

[0005] The technology disclosed herein has been made in light of these points, and its purpose is to improve precision and productivity in additive manufacturing. [Means for solving the problem]

[0006] The additive manufacturing method of the present disclosure includes generating multiple beams, solidifying raw material powder in the powder bed by scanning the multiple beams over the powder bed with a common scanner, and adjusting the alignment direction of the multiple beams on the powder bed by adjusting the alignment direction of multiple irradiation points of the multiple beams upstream of the scanner in conjunction with the scanning of the multiple beams.

[0007] The additive manufacturing apparatus disclosed herein comprises a beam generator that generates multiple beams, a platform that supports a powder bed composed of raw material powder, a common scanner that scans the multiple beams from the beam generator over the powder bed, and a control device that controls the beam generator and the scanner, wherein the beam generator is configured to be able to change the alignment direction of the multiple beams upstream of the scanner, and the control device adjusts the alignment direction of the multiple irradiation points of the multiple beams on the powder bed by adjusting the alignment direction of the multiple beams in conjunction with the scanning of the multiple beams by the scanner. [Effects of the Invention]

[0008] The additive manufacturing method allows for improved accuracy and productivity in additive manufacturing.

[0009] The additive manufacturing device can improve accuracy and productivity in additive manufacturing. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic diagram showing the configuration of an additive manufacturing device. [Figure 2] FIG. 2 is a schematic diagram of a beam generator. [Figure 3] FIG. 3 is a schematic diagram showing the positions of a plurality of beams in a plane perpendicular to one of the plurality of beams. [Figure 4] FIG. 4 is a schematic diagram of a scanner. [Figure 5] FIG. 5 is a schematic diagram showing the locations of multiple irradiation spots on a powder bed. [Figure 6] FIG. 6 is a diagram illustrating a schematic hardware configuration of the control device. [Figure 7] FIG. 7 is a block diagram showing the configuration of a control system of the processor. [Figure 8] FIG. 8 is a schematic diagram illustrating the scanning of multiple beams on the surface of a powder bed. [Figure 9]FIG. 9 is a schematic diagram for explaining the loci of a plurality of irradiation points when a plurality of beams overlap. [Figure 10] FIG. 10 is a schematic diagram for explaining scanning with a plurality of beams that pass along the same trajectory. [Figure 11] FIG. 11 is a schematic diagram illustrating the scanning of multiple beams on the surface of a powder bed in the presence of a stream of inert gas. [Figure 12] FIG. 12 is a schematic diagram showing the configuration of an additive manufacturing device according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0011] Exemplary embodiments will now be described in detail with reference to the accompanying drawings, in which: Figure 1 is a schematic diagram showing the configuration of an additive manufacturing apparatus;

[0012] The additive manufacturing apparatus 100 includes a platform 11 on which raw material powder is placed, a beam generator 2 that generates multiple beams, a common scanner 4 that scans the multiple beams from the beam generator 2 over a powder bed 19 on the platform 11, and a control device 5 that controls the beam generator 2 and the scanner 4. The additive manufacturing apparatus 100 manufactures a molded object by scanning the multiple beams over the powder bed 19 to melt or sinter and solidify the powder material in the surface layer of the powder bed 19. For example, the additive manufacturing apparatus 100 performs layered manufacturing using additive manufacturing with powder bed fusion bonding. Powder bed fusion bonding is a manufacturing method in which raw material powder is spread on the platform 11, the raw material powder is melted or sintered by a beam, and the solidified layers are stacked to form a molded object.

[0013] <Platform> The additive manufacturing apparatus 100 may further include a bed formation apparatus 1 that forms a powder bed 19. The platform 11 is included in the bed formation apparatus 1. In detail, the bed formation apparatus 1 has a platform 11 that can be raised and lowered, a partition wall 13 that defines a space that accommodates the platform 11, a supplier 14 that supplies raw material powder, and a recoater 15.

[0014] The partition wall 13 defines a space that opens upward. The platform 11 moves up and down in the space within the partition wall 13. A base plate 11a may be placed on the platform 11. Raw material powder is spread over the platform 11 and the base plate 11a.

[0015] The supplier 14 is disposed outside the partition wall 13. In this example, the supplier 14 supplies raw material powder to a position outside the partition wall 13. The raw material powder is, for example, a metal powder such as stainless steel, maraging steel, copper alloy, nickel alloy, titanium alloy, aluminum alloy, cobalt-chromium-molybdenum alloy, gold alloy, or platinum-based metallic glass. Alternatively, the raw material powder may be a resin powder such as polyamide (PA), filler-reinforced resin powder, polypropylene (PP), or polystyrene (PS). For example, the supplier 14 includes a partition wall 14a that defines a storage space for the raw material powder and a table 14b that can be raised and lowered within the partition wall 14a. The partition wall 14a is open upward. The raw material powder is placed on the table 14b. The supplier 14 raises the table 14b to discharge a portion of the raw material powder upward from the open end of the partition wall 14a.

[0016] The recoater 15 deposits powder material on the platform 11. The recoater 15 moves the raw material powder supplied from the supplier 14 onto the platform 11 and smoothes and levels the surface of the raw material powder on the platform 11. The recoater 15 reciprocates horizontally above the platform 11. The recoater 15 passes over the powder material supplied by the supplier 14 and also passes horizontally through the opening in the partition wall 13. In other words, the recoater 15 moves the powder material supplied by the supplier 14 onto the platform 11, spreads it over the platform 11, and further smoothes and levels the surface of the powder material on the platform 11.

[0017] The bed formation apparatus 1 is disposed in a chamber 16. The chamber 16 is filled with an inert gas. A gas supplier 17 is disposed in the chamber 16 to supply the inert gas into the chamber 16. For example, the inert gas is nitrogen gas, argon gas, or helium gas. By supplying the inert gas into the chamber 16, the oxygen concentration around the powder bed 19 can be reduced. More specifically, the gas supplier 17 flows the inert gas into the chamber 16 so as to generate a flow of the inert gas along the surface of the powder bed 19. In the example of FIG. 1 , the gas supplier 17 generates a flow of the inert gas along the surface of the powder bed 19 from the back side to the front side of the page.

[0018] <Beam generator> The beam generator 2 generates a plurality of beams that are parallel to one another. The beam generator 2 has one beam source 21 that emits a beam, and a splitter 22 that splits the beam emitted from the beam source 21 into a plurality of beams.

[0019] In this example, the beam is a laser beam, which may be a solid-state laser, a gas laser, or a semiconductor laser, in which case the beam source 21 is a laser oscillator.

[0020] The splitter 22 splits one beam B into multiple beams that are substantially parallel to each other. In this example, the splitter 22 splits the single beam B into multiple beams b1 and b2. When the multiple beams b1 and b2 are distinguished, the beam b1 will be referred to as a first beam b1 and the beam b2 will be referred to as a second beam b2. The multiple beams b1 and b2 emitted from the beam generator 2 are irradiated onto the powder bed 19 via the scanner 4.

[0021] FIG. 2 is a schematic diagram of the beam generator 2. The splitter 22 has a first mirror 22a and a second mirror 22b. Beam B from the beam source 21 is incident on the first mirror 22a. The first mirror 22a is a half mirror that reflects a portion of the incident light and transmits the remainder. A portion of beam B incident on the first mirror 22a is reflected toward the second mirror 22b, and the remainder of beam B transmits through the first mirror 22a. The beam that transmits through the first mirror 22a is the first beam b1. The beam reflected by the first mirror 22a is the second beam b2. For example, the first mirror 22a reflects 50% of the incident beam B and transmits the remaining 50%. Note that the ratio of reflection to transmission is not limited to this. For example, the reflection rate may be 30% and the transmission rate may be 70%. The second mirror 22b is a total reflection mirror. The second beam b2 from the first mirror 22a is incident on the second mirror 22b. The second mirror 22b reflects the second beam b2 in a direction substantially parallel to the first beam b1.

[0022] The splitter 22 may have an adjuster 23 that adjusts the distance between the first beam b1 and the second beam b2. For example, the adjuster 23 is an actuator that moves the second mirror 22b. The adjuster 23 adjusts the distance of the second mirror 22b to the first mirror 22a. When the adjuster 23 moves the second mirror 22b closer to the first mirror 22a, the distance between the first beam b1 and the second beam b2 decreases. When the adjuster 23 moves the second mirror 22b away from the first mirror 22a, the distance between the first beam b1 and the second beam b2 increases.

[0023] The beam generator 2 is configured to be able to change the alignment direction S1 of the multiple beams b1 and b2 upstream of the scanner 4. Specifically, the beam generator 2 is configured to be rotatable about a rotation axis A1 parallel to the multiple beams b1 and b2 emitted from the beam generator 2, and the alignment direction S1 of the multiple beams b1 and b2 is changed by rotating about the rotation axis A1. In this example, the rotation axis A1 is located between the first beam b1 and the second beam b2. In a plane perpendicular to the rotation axis A1, the first beam b1, the rotation axis A1, and the second beam b2 are aligned on a straight line. The beam generator 2 has an actuator 24 that rotates at least the splitter 22 about the rotation axis A1. For example, the actuator 24 is a motor such as a servo motor. This allows the alignment direction S1 of the multiple beams b1 and b2 to be changed. Note that the actuator 24 may also rotate the beam source 21 together with the splitter 22 about the rotation axis A1 in addition to the splitter 22. Since the beam generator 2 is disposed on the upstream side of the scanner 4, the beam generator 2 changes the direction S1 in which the multiple beams b1 and b2 are arranged on the upstream side of the scanner 4.

[0024] FIG. 3 is a schematic diagram showing the positions of the beams b1 and b2 in a plane perpendicular to one of the beams b1 and b2. The direction S1 in which the beams b1 and b2 are aligned is the direction in which the beams b1 and b2 are aligned in a plane perpendicular to the beam. For example, the direction S1 in which the beams b1 and b2 are aligned is determined by using one of the beams b1 and b2 as a reference and the positions of the other beams in a circumferential direction around the first beam b1. For example, the direction S1 in which the first beam b1 and the second beam b2 are aligned is determined by the position of the second beam b2 in a circumferential direction around the first beam b1, i.e., the angular position of the second beam b2 around the first beam b1. In the example of FIG. 3, the direction S1 in which the first beam b1 and the second beam b2 are aligned, indicated by a solid line, is vertically downward. As the beam generator 2 rotates counterclockwise around the rotation axis A1, the first beam b1 moves to the lower left and the second beam b2 moves to the upper right, as shown by the two-dot chain lines, so that the direction S1 in which the first beam b1 and the second beam b2 are aligned points diagonally downward to the right.

[0025] The beam generator 2 may further include at least one of a collimator and a focus lens. The collimator converts each laser beam into a parallel beam. The focus lens adjusts the focal position of the laser beam to change the spot diameter of the laser beam on the powder bed 19. When the beam generator 2 includes a collimator, a focus lens, etc., in addition to the splitter 22, the collimator, the focus lens, etc. may also rotate integrally with the splitter 22 around the rotation axis A1.

[0026] <Scanner> FIG. 4 is a schematic diagram of the scanner 4. The scanner 4 scans the multiple beams b1 and b2 emitted from the beam generator 2 on the powder bed 19. The scanner 4 is common to the multiple beams b1 and b2. That is, the multiple beams b1 and b2 are incident on a single scanner 4. The scanner 4 includes a galvanometer mirror 41 and an actuator 42 that adjusts the angle of the galvanometer mirror 41. The galvanometer mirror 41 reflects the multiple beams b1 and b2 and irradiates the multiple beams b1 and b2 onto the powder bed 19. The galvanometer mirror 41 adjusts the reflection angles of the multiple beams b1 and b2 to move the irradiation points of the multiple beams b1 and b2 on the powder bed 19. In this example, the galvanometer mirror 41 moves the irradiation points of the multiple beams b1 and b2 two-dimensionally. Specifically, the galvanometer mirror 41 includes a first galvanometer mirror 41A and a second galvanometer mirror 41B. The first galvanometer mirror 41A reflects the beams b1 and b2 incident on the scanner 4 and directs them toward the second galvanometer mirror 41B. The second galvanometer mirror 41B reflects the beams b1 and b2 from the first galvanometer mirror 41A toward the powder bed 19. The actuator 42 includes a first motor 42A that rotates the first galvanometer mirror 41A about a first rotation axis and a second motor 42B that rotates the second galvanometer mirror 41B about a second rotation axis. As the first galvanometer mirror 41A rotates, the irradiation points of the beams b1 and b2 move in a first direction on the surface of the powder bed 19. As the second galvanometer mirror 41B rotates, the irradiation points of the beams b1 and b2 move in a second direction on the surface of the powder bed 19. The second direction is perpendicular to the first direction.

[0027] The scanner 4 may include an fθ lens 43. The multiple beams b1 and b2 from the galvanometer mirror 41 are incident on the fθ lens 43. The fθ lens 43 focuses the multiple beams b1 and b2 on the surface of the powder bed 19.

[0028] The scanner 4 emits multiple beams b1 and b2, reflecting the adjustment of the alignment direction S1 of the multiple beams b1 and b2 upstream of the scanner 4. Therefore, when the alignment direction S1 of the multiple beams b1 and b2 emitted from the beam generator 2 is changed, the alignment direction S2 of the irradiation points p1 and p2 of the multiple beams b1 and b2 on the powder bed 19 also changes. Figure 5 is a schematic diagram showing the positions of the multiple irradiation points p1 and p2 on the powder bed 19. The alignment direction S2 of the multiple irradiation points p1 and p2 is determined, for example, based on one of the multiple irradiation points p1 and p2 and is determined by the position of the other irradiation points in the circumferential direction around that irradiation point. For example, the alignment direction S2 of the first irradiation point p1 and the second irradiation point p2 is determined by the position of the second irradiation point p2 in the circumferential direction around the first irradiation point p1, i.e., the angular position of the second irradiation point p2 around the first irradiation point p1. In the example of FIG. 5, the direction S2 in which the first irradiation point p1 and the second irradiation point p2 are aligned, indicated by a solid line, is vertically downward. By changing the direction S1 in which the beams b1 and b2 are aligned, the first irradiation point p1 may move downward and left, and the second irradiation point p2 may move upward and right, as indicated by a two-dot chain line. As a result, the direction S2 in which the first irradiation point p1 and the second irradiation point p2 are aligned becomes oriented diagonally downward and right. The geometrical positional relationship between the multiple irradiation points p1 and p2 and the rotation axis A2 corresponds to the geometrical positional relationship between the multiple beams b1 and b2 emitted from the beam generator 2 and the rotation axis A1. In this example, the rotation axis A2 is located at the midpoint between the first irradiation point p1 and the second irradiation point p2, and the rotation axis A1 is located at the center between the first beam b1 and the second beam b2.

[0029] <Control device> 6 is a diagram showing a schematic hardware configuration of the control device 5. The control device 5 controls the bed formation device 1 in addition to the beam generator 2 and scanner 4. For example, the control device 5 causes the bed formation device 1 to form a powder bed 19, causes the beam generator 2 to generate multiple beams b1 and b2, and causes the scanner 4 to scan the multiple beams b1 and b2 over the powder bed 19, thereby melting or sintering the raw material powder and solidifying it. The control device 5 repeats this process to manufacture a molded object.

[0030] The control device 5 includes a processor 51 , a storage device 52 , and a memory 53 .

[0031] The processor 51 controls the entire control device 5. The processor 51 performs various types of arithmetic processing. For example, the processor 51 is formed of a processor such as a CPU (Central Processing Unit). The processor 51 may also be formed of an MCU (Micro Controller Unit), an MPU (Micro Processor Unit), an FPGA (Field Programmable Gate Array), a PLC (Programmable Logic Controller), a system LSI, or the like.

[0032] The storage unit 52 stores programs to be executed by the processor 51 and various data. For example, the storage unit 52 stores a robot control program. The storage unit 52 is formed of a non-volatile memory, a hard disk drive (HDD), a solid state drive (SSD), or the like. The memory 53 temporarily stores data and the like. For example, the memory 53 is formed of a volatile memory.

[0033] 7 is a block diagram showing the configuration of the control system of the processor 51. The processor 51 realizes various functions by reading out the robot control program from the storage device 52 into the memory 53 and expanding it. Specifically, the processor 51 functions as a floor controller 55 that controls the floor forming device 1, a beam controller 56 that controls the beam generator 2, a scan controller 57 that controls the scanner 4, and an overall controller 58 that controls the beam controller 56 and the scan controller 57 overall.

[0034] The overall controller 58 generates operation commands to the beam controller 56 and the scan controller 57 to form the target object. The overall controller 58 generates the operation commands based on a numerical control program for manufacturing the target object. The numerical control program may be created by the overall controller 58 or may be created externally. The numerical control program is created based on CAD data of the target object. The overall controller 58 outputs operation commands to both the beam controller 56 and the scan controller 57, causing the beam controller 56 and the scan controller 57 to perform cooperative control. Furthermore, the overall controller 58 also generates operation commands for overall control of the floor controller 55. In other words, the overall controller 58 causes the floor controller 55, the beam controller 56, and the scan controller 57 to perform cooperative control.

[0035] The bed controller 55 controls the platform 11, the feeder 14, and the recoater 15 to form the powder bed 19. For example, the bed controller 55 lowers the platform 11. This forms a step between the open end of the partition wall 13 and the platform 11. If the powder bed 19 has already been formed, a step forms between the open end of the partition wall 13 and the surface of the existing powder bed 19. The bed controller 55 causes the feeder 14 to feed the raw material powder. Specifically, the bed controller 55 raises the table 14b by a predetermined amount to discharge the raw material powder above the open end of the partition wall 14a. Next, the bed controller 55 operates the recoater 15 to move the raw material powder fed by the feeder 14 onto the platform 11. The raw material powder is spread over the step between the open end of the partition wall 13 and the platform 11 or the surface of the existing powder bed 19. The spread raw material powder is smoothed by the recoater 15. Thus, a powder bed 19 is formed.

[0036] The beam controller 56 causes the beam source 21 to emit the beam B. At this time, the beam controller 56 adjusts the output of the beam, that is, the laser output.

[0037] The scan controller 57 operates the galvanometer mirror 41 to scan the multiple beams b1 and b2 over the powder bed 19. As a result, portions of the raw powder in the powder bed 19 corresponding to the trajectories of the multiple beams b1 and b2 melt and solidify, forming an object having a shape corresponding to the trajectories of the multiple beams b1 and b2. The scan controller 57 scans the multiple beams b1 and b2 to trace any desired trajectory on the powder bed 19, for example, a curved or bent trajectory. At this time, the beam controller 56 operates the actuator 24 to adjust the direction S1 in which the multiple beams b1 and b2 are aligned. In other words, the beam controller 56 adjusts the direction S1 in which the multiple beams b1 and b2 are aligned in conjunction with the scanning of the multiple beams b1 and b2.

[0038] <Adjusting the alignment direction of multiple beams> The beam controller 56 coordinates the scanning of the beams b1 and b2 and the adjustment of the alignment direction S1 of the beams b1 and b2 in various ways.

[0039] FIG. 8 is a schematic diagram illustrating the scanning of the beams b1 and b2 on the surface of the powder bed 19. For example, the beam controller 56 adjusts the direction S1 of the beams b1 and b2 in conjunction with the scanner 4, i.e., in conjunction with the scanning of the beams b1 and b2, so that the angle α of the direction S2 of the irradiation points p1 and p2 relative to the scanning direction T of the beams b1 and b2 is constant. In FIG. 8, the beams b1 and b2 scan the powder bed 19 to trace an arc-shaped trajectory. Hereinafter, the angle α of the direction S2 of the irradiation points p1 and p2 relative to the scanning direction T of the beams b1 and b2 will also be referred to as the "angle α of the direction S2 of the irradiation points p1 and p2." The scanning direction T of the beams b1 and b2 is the direction of movement of the beams b1 and b2 on the surface of the powder bed 19, i.e., the direction of movement of the irradiation points p1 and p2 of the beams b1 and b2 on the surface of the powder bed 19. When distinguishing between the multiple irradiation points p1 and p2, the irradiation point of the first beam b1 is referred to as the first irradiation point p1, and the irradiation point of the second beam b2 is referred to as the second irradiation point p2.

[0040] Scanning of the first beam b1 forms a filamentary object a1 corresponding to the trajectory of the first beam b1. Scanning of the second beam b2 forms a filamentary object a2 corresponding to the trajectory of the second beam b2. By scanning multiple beams b1 and b2 together on the powder bed 19, multiple filamentary objects a1 and a2 are formed simultaneously. For example, the objects a1 and a2 are fins of a heat exchanger. By stacking the filamentary objects a1 and a2, plate-like fins extending in the stacking direction are formed.

[0041] At this time, the direction S1 in which the beams b1 and b2 are aligned is adjusted so that the angle α of the direction S2 in which the irradiation points p1 and p2 are aligned is constant. As a result, even when the beams b1 and b2 are scanned to trace curved or bent trajectories on the powder bed 19, multiple substantially parallel linear objects a1 and a2, i.e., multiple linear objects a1 and a2 with a constant interval between them, are simultaneously formed.

[0042] In the example of Figure 8, the beam controller 56 adjusts the direction S1 of the beams b1 and b2 in conjunction with the scanning of the beams b1 and b2 so that the angle α of the direction S2 of the irradiation points p1 and p2 becomes a right angle. Here, "right angle" means a substantially right angle, for example, an angle in the range of 90°±10°. By making the angle α of the direction S2 of the irradiation points p1 and p2 a right angle, the distance between the simultaneously formed objects a1 and a2 can be made relatively wide.

[0043] At this time, the beam controller 56 can change the spacing between the multiple objects formed simultaneously by changing the angle α of the direction S2 in which the multiple irradiation points p1 and p2 are aligned, which is maintained constant. For example, the beam controller 56 may adjust the direction S1 in which the multiple beams b1 and b2 are aligned in conjunction with the scanning of the multiple beams b1 and b2 so that the angle α of the direction S2 in which the multiple irradiation points p1 and p2 are aligned is constant and smaller than a right angle. As a result, although one of the multiple beams b1 and b2 leads the other beams in the scanning direction T, the distance between the multiple beams b1 and b2 in the direction perpendicular to the scanning direction T is shortened. As a result, the spacing between the multiple objects a1 and a2 formed simultaneously becomes relatively narrow.

[0044] The beam controller 56 may adjust the direction S1 of the beams b1 and b2 in conjunction with the scanner 4, i.e., in conjunction with the scanning of the beams b1 and b2, so that the angle α of the direction S2 of the irradiation points p1 and p2 falls within a certain range. This allows the formation of multiple filamentary objects a1 and a2 simultaneously while maintaining the spacing between the filamentary objects a1 and a2 within a certain range, even when the beams b1 and b2 are scanned to trace a curved or bent trajectory on the powder bed 19. In this case, the spacing between the filamentary objects a1 and a2 can be changed within a certain range. The certain range may include, for example, 90°.

[0045] The beam controller 56 may adjust the direction S1 in which the multiple beams b1 and b2 are arranged in conjunction with the scanner 4 so that the angle α of the direction S2 in which the multiple irradiation points p1 and p2 are arranged varies depending on the scanning position. This makes it possible to simultaneously form multiple linear objects a1 and a2 whose intervals vary flexibly.

[0046] FIG. 9 is a schematic diagram illustrating the trajectories of multiple irradiation points p1 and p2 when multiple beams b1 and b2 overlap. The multiple beams b1 and b2 may partially overlap. However, the optical axes of the multiple beams b1 and b2 are spaced apart from each other in the direction S1 in which the multiple beams b1 and b2 are arranged. In other words, the irradiation point p1 of the first beam b1 and the irradiation point p2 of the second beam b2 may partially overlap. For example, the beam controller 56 can cause the multiple beams b1 and b2 to partially overlap by increasing the spot diameter of the multiple beam controllers 56. The beam controller 56 can increase the spot diameter by increasing the output of the beam source 21 or adjusting the focal position using a focus lens.

[0047] In this case, the multiple linear objects a1 and a2 partially overlap to form a single thick linear object. By maintaining a constant angle α of the direction S2 in which the multiple irradiation points p1 and p2 are arranged, the thickness of the single linear object is maintained constant. Note that the angle α of the direction S2 in which the multiple irradiation points p1 and p2 are arranged may be changed depending on the scan. This allows the thickness of the single thick linear object to be adjusted.

[0048] The beam controller 56 can also cause the beams b1 and b2 generated by the splitter 22 to partially overlap by reducing the spacing between the beams b1 and b2, specifically, the spacing in the direction S1 in which the beams b1 and b2 are aligned. If the splitter 22 has an adjuster 23 that adjusts the spacing between the first beam b1 and the second beam b2, the splitter 22 can change the spacing in the direction S1 in which the beams b1 and b2 are aligned. The beam controller 56 controls the adjuster 23 to reduce the spacing between the beams b1 and b2 in the direction S1 to the extent that the beams b1 and b2 partially overlap. As a result, the beams b1 and b2 are emitted from the splitter 22 in a partially overlapping state.

[0049] The beam controller 56 can also form the partially overlapping linear objects a1 and a2 by reducing the angle α of the direction S2 in which the multiple irradiation points p1 and p2 are arranged. As described above, reducing the angle α of the direction S2 in which the multiple irradiation points p1 and p2 are arranged shortens the distance between the multiple irradiation points p1 and p2 in the direction perpendicular to the scanning direction T. The beam controller 56 adjusts the angle α of the direction S2 in which the multiple irradiation points p1 and p2 are arranged to such an extent that the multiple irradiation points p1 and p2 partially overlap when viewed in the scanning direction T, and adjusts the direction S1 in which the multiple beams b1 and b2 are arranged in conjunction with the scanning of the multiple beams b1 and b2 to maintain this state. This forms the partially overlapping linear objects a1 and a2, resulting in the formation of a single thick linear object.

[0050] Furthermore, the beam controller 56 may adjust the thickness of a single line formed by the overlapping of multiple linear objects a1, a2 by adjusting the direction S1 in which the multiple beams b1, b2 are arranged in conjunction with the scanning of the multiple beams b1, b2 within a range in which the multiple irradiation points p1, p2 overlap when viewed in the scanning direction T.

[0051] FIG. 10 is a schematic diagram illustrating scanning by multiple beams that travel along the same trajectory. The beam controller 56 may adjust the direction S1 of the multiple beams b1 and b2 in conjunction with the scanner 4, i.e., in conjunction with the scanning of the multiple beams b1 and b2, so that one of the multiple beams b1 and b2 travels along the same scanning trajectory as the other of the multiple beams b1 and b2. That is, the beam controller 56 adjusts the direction S1 of the multiple beams b1 and b2 in conjunction with the scanner 4 so that the direction S2 of the multiple irradiation points p1 and p2 coincides with the scanning direction T. As a result, the multiple beams b1 and b2 move along approximately the same trajectory on the powder bed 19. The subsequent beams intermittently or continuously irradiate the portion of the powder bed 19 irradiated by the preceding beam. As a result, the same portion of the powder bed 19 is irradiated by the multiple beams b1 and b2 with a short time difference. For example, a portion of the powder bed 19 can be preheated by irradiating it with a leading beam and then melted by irradiating it with a trailing beam. This allows for adjustment of the cooling rate. Adjusting the cooling rate can reduce residual stress. Furthermore, it can improve the formability of materials that are highly susceptible to cracking. When performing such scanning, it is preferable that the power of the leading beam is smaller than that of the trailing beam. The power of the leading beam is more preferably an power that preheats the raw material powder but does not melt it. For example, the ratio of the reflection and transmission of the beams of the first mirror 22a in the splitter 22 is set to a value other than 1:1. For example, the first mirror 22a reflects and transmits the incident beam B so that the power of the first beam b1:the power of the second beam b2 is 3:7. The beam controller 56 causes the first beam b1 to precede the second beam b2 in the scanning direction T. Note that this power ratio is merely an example. Alternatively, a portion of the powder bed 19 can be melted by irradiating it with a leading beam and then post-heated by irradiating it with a trailing beam. In that case, the power of the subsequent beam is preferably less than the power of the preceding beam.

[0052] 11 is a schematic diagram illustrating the scanning of multiple beams b1 and b2 on the surface of powder bed 19 where an inert gas flow is present. There may be an inert gas flow along the surface of powder bed 19. When the scanning direction T of the multiple beams b1 and b2 intersects with the flow direction F of the inert gas, the beam controller 56 may adjust the alignment direction S1 of the multiple beams b1 and b2 in conjunction with the scanner 4, i.e., in conjunction with the scanning of the multiple beams b1 and b2, so that, among the multiple irradiation points p1 and p2, the irradiation points located downstream in the flow direction F precede the irradiation points located upstream in the flow direction F in the scanning direction T.

[0053] In the example of FIG. 11, an inert gas flow is generated along the surface of the powder bed 19 in the flow direction F. The scan controller 57 scans multiple beams b1 and b2 in a direction intersecting the flow direction F. In this example, the scanning direction T is substantially linear and substantially perpendicular to the flow direction F. The first irradiation point p1 is located upstream of the flow direction F, and the second irradiation point p2 is located downstream of the flow direction F. In this case, the beam controller 56 adjusts the alignment direction S1 of the multiple beams b1 and b2 in conjunction with the scanner 4 so that the second irradiation point p2 precedes the first irradiation point p1 in the scanning direction T. When the beam is irradiated onto the powder bed 19, spatter or fumes (hereinafter referred to as "spatter, etc.") may be generated. The spatter, etc. is carried away by the inert gas flow. The spatter, etc. is likely to scatter downstream of the beam irradiation point in the flow direction F. Because the preceding second irradiation point p2 is located downstream of the succeeding first irradiation point p1 in the flow direction F, spatters and the like generated by irradiation with the second beam b2 are less likely to scatter into the area to be irradiated with the first beam b1. This reduces the amount of spatters and the like that scatter into the area to be irradiated with the succeeding first beam b1. This reduces the impact of spatters and the like on the formation of an object by irradiation with the first beam b1.

[0054] Furthermore, it is preferable that the beam controller 56 executes control to advance the irradiation point located downstream of the flow direction F when the angle of the scanning direction T with respect to the flow direction F is within a predetermined range including 90°. For example, the range is 30° to 150°. The closer the angle of the scanning direction T with respect to the flow direction F is to 90°, the greater the influence of sputtering and the like caused by the irradiation of the preceding beam on the formation of an object by the irradiation of the subsequent beam. In other words, by executing control to advance the irradiation point located downstream of the flow direction F when the angle of the scanning direction T with respect to the flow direction F is within a predetermined range including 90°, the effect of reducing the influence of sputtering and the like on the formation of an object by the irradiation of the subsequent beam can be further enhanced.

[0055] In the additive manufacturing apparatus 100 configured as described above, scanning is performed using multiple beams b1 and b2, thereby forming multiple objects a1 and a2 in a single scan (including cases where a single object is formed by overlapping the objects a1 and a2), thereby improving productivity. At this time, the alignment direction S1 of the multiple beams b1 and b2 is adjusted in conjunction with the scanning of the multiple beams b1 and b2. This allows the alignment direction S2 of the multiple irradiation points p1 and p2 on the powder bed 19 to be changed according to the scanning direction T of the multiple beams b1 and b2. Adjusting the alignment direction S2 of the multiple irradiation points p1 and p2 relative to the scanning direction T enables relatively flexible object production. For example, adjusting the angle α of the alignment direction S2 of the multiple irradiation points p1 and p2 adjusts the spacing between the multiple linear objects a1 and a2. Adjusting the angle α of the alignment direction S2 of the multiple irradiation points p1 and p2 allows the multiple linear objects a1 and a2 to be overlapped to produce a single filamentary object and adjust the thickness of the single filamentary object. By adjusting the angle α of the direction S2 in which the multiple irradiation points p1 and p2 are arranged, it is possible to adjust which of the multiple irradiation points p1 and p2 leads in the scanning direction T, and how far one of the multiple irradiation points p1 and p2 leads the other.

[0056] In addition, the alignment direction S1 of the multiple beams b1, b2 is adjusted upstream of the scanner 4. If the alignment direction S1 of the multiple beams b1, b2 is adjusted downstream of the scanner 4, the positions of the multiple beams b1, b2 determined by the scanner 4 may be affected by the adjustment of the alignment direction S1 of the multiple beams b1, b2. By adjusting the alignment direction S1 of the multiple beams b1, b2 upstream of the scanner 4, the impact on the positioning of the multiple beams b1, b2 by the scanner 4 can be reduced. In other words, the scanning accuracy of the scanner 4 is improved.

[0057] Furthermore, by scanning the multiple beams b1 and b2 using a common scanner 4, control of the scanner 4 can be simplified and the accuracy of adjusting the direction S1 of the multiple beams b1 and b2 can be improved. More specifically, if multiple beams b1 and b2 are scanned using corresponding scanners, the scanning positions of the corresponding beams are adjusted by each scanner, and the direction S1 of the multiple beams b1 and b2 is adjusted by multiple scanners. In this case, control of each scanner becomes complex, and the scanning accuracy of the scanner affects the accuracy of adjusting the direction S1 of the multiple beams b1 and b2. By scanning the multiple beams b1 and b2 using a common scanner 4, control of the scanner 4 can be concentrated on adjusting the scanning positions of the multiple beams b1 and b2, and adjustment of the direction S1 of the multiple beams b1 and b2 can be separated from control of the scanner 4. Furthermore, because the multiple beams b1 and b2 are incident on and emitted from the common scanner 4, the multiple beams b1 and b2 are emitted from the scanner 4 without significant changes in their relative positional relationship. That is, the multiple beams b1 and b2 are emitted from the scanner 4 while the relative positional relationship between the multiple beams b1 and b2 adjusted on the upstream side of the scanner 4 is generally maintained. This improves the accuracy of adjusting the direction S1 in which the multiple beams b1 and b2 are aligned.

[0058] <<Variation>> Next, an additive manufacturing apparatus 200 according to a modified example will be described. Fig. 12 is a schematic diagram showing the configuration of the additive manufacturing apparatus 200 according to a modified example. The additive manufacturing apparatus 200 differs from the additive manufacturing apparatus 100 in the configuration of the beam generator 202. The following description will focus on the parts of the configuration of the additive manufacturing apparatus 200 that differ from the additive manufacturing apparatus 100.

[0059] The beam generator 202 generates a plurality of beams that are parallel to one another. The beam generator 202 includes a plurality of beam sources 221A and 221B that emit a plurality of beams b1 and b2, and a converger 222 that collimates the plurality of beams b1 and b2 emitted from the plurality of beam sources 221A and 221B and adjusts the spacing between the plurality of beams b1 and b2. The beam generator 202 causes the plurality of parallel beams b1 and b2 to be incident on a common scanner 4.

[0060] In this example, the number of beam sources 221A and 221B is two. When distinguishing between the beam sources 221A and 221B, the beam source 221A will be referred to as the first beam source 221A and the beam source 221B will be referred to as the second beam source 221B. The first beam source 221A emits a first beam b1. The second beam source 221B emits a second beam b2. The first beam source 221A and the second beam source 221B have the same configuration. For example, the first beam source 221A and the second beam source 221B have the same configuration as the beam source 21. The beams b1 and b2 emitted from the first beam source 221A and the second beam source 221B are incident on the convergent 222.

[0061] The converging device 222 includes a mirror, a lens, or a prism, and adjusts the beams b1 and b2 to be parallel and adjusts the interval between the beams b1 and b2 to a predetermined interval. The converging device 222 can adjust the interval between the parallel beams b1 and b2 within a predetermined range by adjusting the position of the mirror, lens, or prism.

[0062] The beam generator 202 is configured to be able to change the direction S1 in which the multiple beams b1 and b2 are aligned on the upstream side of the scanner 4. Specifically, the beam generator 202 is configured to be rotatable about a rotation axis A1 parallel to the multiple beams b1 and b2 emitted from the beam generator 202, and changes the direction S1 in which the multiple beams b1 and b2 are aligned by rotating about the rotation axis A1. The beam generator 202 has an actuator 224 that rotates the multiple beam sources 221A and 221B and the converger 222 integrally about the rotation axis A1. For example, the actuator 224 is a motor such as a servo motor. This allows the direction S1 in which the multiple beams b1 and b2 are aligned to be changed. Since the beam generator 202 is disposed upstream of the scanner 4, the beam generator 202 changes the direction S1 in which the multiple beams b1 and b2 are aligned on the upstream side of the scanner 4.

[0063] The additive manufacturing apparatus 200 configured in this manner achieves the same effects as the additive manufacturing apparatus 100. Specifically, in the additive manufacturing apparatus 200, scanning is performed using multiple beams b1 and b2, so multiple objects a1 and a2 are formed in a single scan (including cases where a single object is formed by overlapping the objects a1 and a2), thereby improving productivity. At this time, the alignment direction S1 of the multiple beams b1 and b2 is adjusted in conjunction with the scanning of the multiple beams b1 and b2, allowing for relatively flexible object manufacturing. In addition, the alignment direction S1 of the multiple beams b1 and b2 is adjusted upstream of the scanner 4, so both the adjustment accuracy of the alignment direction S1 of the multiple beams b1 and b2 and the scanning accuracy of the scanner 4 can be improved.

[0064] Furthermore, since multiple beams b1 and b2 are generated by multiple beam sources 221A and 221B, the outputs of the multiple beams b1 and b2 can be adjusted independently of each other. This is particularly effective when performing a process in which the multiple beams b1 and b2 pass along the same scanning trajectory, as described above, because the outputs of the preceding beam and the succeeding beam in the scanning direction T can be adjusted independently of each other. In other words, it is easy to set the output of the preceding beam relatively low while setting the output of the succeeding beam relatively high.

[0065] The number of beam sources is not limited to two, and may be three or more. The converging device 222 may not adjust the spacing between the beams b1 and b2 within a predetermined range, but may simply adjust the spacing to a fixed value.

[0066] Other Embodiments As described above, the above embodiment has been described as an example of the technology disclosed in this application. However, the technology of the present disclosure is not limited to this and can be applied to embodiments in which modifications, substitutions, additions, omissions, etc. are made as appropriate. Furthermore, the components described in the above embodiment can be combined to create new embodiments. Furthermore, the components described in the accompanying drawings and detailed description may include not only components essential for solving the problem, but also components that are not essential for solving the problem in order to exemplify the technology. Therefore, the fact that these non-essential components are described in the accompanying drawings or detailed description should not be interpreted as immediately determining that these non-essential components are essential.

[0067] For example, the configurations of the additive manufacturing apparatuses 100, 200 are merely examples. For example, the bed formation apparatus 1 or the scanner 4 may have any configuration. For example, the supply 14 of the bed formation apparatus 1 may be a hopper that supplies raw material powder. The number of beams included in the additive manufacturing apparatuses 100, 200 is not limited to two, and may be three or more. For example, three or more beams may be incident on a common single scanner 4.

[0068] The additive manufacturing apparatus 100, 200 may include multiple scanners. That is, the additive manufacturing apparatus 100, 200 may include another scanner in addition to the single scanner 4 onto which multiple beams b1, b2, whose alignment direction S1 is adjustable, are incident. The other scanner may scan a single beam or multiple beams. For example, the additive manufacturing apparatus 100, 200 may include multiple sets of beam generators 2 or 202 and scanners 4, each of which emits multiple beams b1, b2, whose alignment direction S1 is adjustable.

[0069] The configuration of the splitter 22 is not limited to the above-described configuration. The splitter 22 may include a prism or a lens in addition to or instead of a mirror. The function of the splitter 22 to adjust the distance between the first beam b1 and the second beam b2 may be omitted.

[0070] The definition of the direction S1 in which the multiple beams b1 and b2 are aligned is not limited to the above definition. The direction S1 in which the multiple beams b1 and b2 are aligned can be defined in any way as long as it defines the relative geometric positional relationship between the multiple beams b1 and b2 in a plane perpendicular to one of the multiple beams b1 and b2. When the number of multiple beams is three or more, the direction S1 in which the multiple beams are aligned can be defined by the orientation of a polygon having the multiple beams as vertices.

[0071] Similarly, the definition of the direction S2 in which the multiple irradiation points p1 and p2 are arranged is not limited to the above definition. The direction S2 in which the multiple irradiation points p1 and p2 are arranged can be defined in any way as long as it defines the relative geometric positional relationship between the multiple irradiation points p1 and p2 on the surface of the powder bed 19. When the number of multiple irradiation points is three or more, the direction S2 in which the multiple irradiation points are arranged can be defined by the orientation of a polygon with the multiple irradiation points as vertices.

[0072] The functions performed by the components described herein may be implemented in circuitry or processing circuitry, including general-purpose processors, application-specific processors, integrated circuits, ASICs (Application Specific Integrated Circuits), a CPU (a Central Processing Unit), conventional circuits, and / or combinations thereof, programmed to perform the described functions. A processor includes transistors and other circuits and is considered a circuit or processing circuit. A processor may also be a programmable processor that executes a program stored in a memory.

[0073] In this specification, a circuit, unit, or means is hardware that is programmed to realize or performs the described functions, which may be any hardware disclosed herein or any hardware known to be programmed to realize or perform the described functions.

[0074] If the hardware is a processor considered to be a type of circuitry, the circuit, means, or unit is a combination of hardware and software used to configure the hardware and / or processor.

[0075] [Aspect] The above embodiments are specific examples of the following aspects.

[0076] (Embodiment 1) An additive manufacturing method includes generating multiple beams b1, b2, solidifying raw material powder in the powder bed 19 by scanning the multiple beams b1, b2 over the powder bed 19 with a common scanner 4, and adjusting the direction S2 in which multiple irradiation points p1, p2 of the multiple beams b1, b2 are arranged on the powder bed 19 by adjusting the direction S1 in which the multiple beams b1, b2 are arranged upstream of the scanner 4 in conjunction with the scanning of the multiple beams b2, b2.

[0077] According to this configuration, the direction S2 in which the multiple irradiation points p1, p2 of the multiple beams b1, b2 on the powder bed 19 are arranged can be flexibly changed according to the scanning direction T of the multiple beams b1, b2. This allows for relatively free object formation. At this time, the direction S1 in which the multiple beams b1, b2 are arranged is adjusted upstream of the scanner 4, and the multiple beams b1, b2 whose arrangement direction S1 has been adjusted are scanned by the common scanner 4. This reduces the impact of scanning by the scanner 4 on the adjustment accuracy of the direction S2 in which the multiple irradiation points p1, p2 are arranged, and as a result, the adjustment accuracy of the direction S2 in which the multiple irradiation points p1, p2 are arranged can be improved.

[0078] (Embodiment 2) In the additive manufacturing method described in embodiment 1, when adjusting the direction S1 in which the multiple beams b1, b2 are aligned, the direction S1 in which the multiple beams b1, b2 are aligned is adjusted in conjunction with the scanning of the multiple beams b1, b2 so that the angle α of the direction S2 in which the multiple irradiation points p1, p2 are aligned relative to the scanning direction T of the multiple beams b1, b2 is constant.

[0079] This configuration allows the spacing between the linear objects a1 and a2 formed by the multiple beams b1 and b2 to be kept constant. For example, multiple parallel linear objects a1 and a2 having complex shapes such as curved or bent shapes can be simultaneously formed by the multiple beams b1 and b2.

[0080] (Embodiment 3) In the additive manufacturing method described in embodiment 1 or embodiment 2, when adjusting the direction S1 in which the multiple beams b1, b2 are aligned, the direction S1 in which the multiple beams b1, b2 are aligned is adjusted in conjunction with the scanning of the multiple beams b1, b2 so that the angle α of the direction S2 in which the multiple irradiation points p1, p2 are aligned relative to the scanning direction T of the multiple beams b1, b2 is a right angle.

[0081] According to this configuration, the distance between the plurality of linear objects a1 and a2 formed by the plurality of beams b1 and b2 can be made relatively wide.

[0082] (Aspect 4) In the additive manufacturing method described in any one of aspects 1 to 3, when adjusting the direction S1 in which the multiple beams b1, b2 are arranged, the direction S1 in which the multiple beams b1, b2 are arranged is adjusted in conjunction with the scanning of the multiple beams b1, b2 so that one of the multiple irradiation points p1, p2 passes along the trajectory passed by the other of the multiple irradiation points p1, p2.

[0083] According to this configuration, the multiple linear objects a1, a2 formed by the multiple beams b1, b2 can be overlapped without changing the spacing between the multiple beams b1, b2. Furthermore, by adjusting the angle α of the direction S2 in which the multiple irradiation points p1, p2 are arranged with respect to the scanning direction T within a range where one of the multiple irradiation points p1, p2 maintains a state in which the other of the multiple irradiation points p1, p2 passes along the trajectory that the other of the multiple irradiation points p1, p2 passed, the thickness of the single linear object formed by the overlapping of the multiple linear objects a1, a2 can be adjusted.

[0084] (Embodiment 5) An additive manufacturing method according to any one of embodiments 1 to 4, further comprising generating a flow of inert gas along the surface of the powder bed 19, and adjusting the direction S1 of alignment of the multiple beams b1, b2, by adjusting the direction S1 of alignment of the multiple beams b1, b2 in conjunction with the scanning of the multiple beams b1, b2 so that, when the scanning direction T of the multiple beams b1, b2 intersects with the flow direction F of the inert gas, the irradiation point of the multiple irradiation points p1, p2 located downstream of the flow direction F precedes the irradiation point located upstream of the flow direction F in the scanning direction T.

[0085] According to this configuration, the influence of sputtering and the like caused by irradiation of a preceding beam in the scanning direction T on the formation of an object by a subsequent beam in the scanning direction T can be reduced.

[0086] (Aspect 6) In the additive manufacturing method described in any one of aspects 1 to 5, adjusting the direction S1 in which the multiple beams b1, b2 are aligned is accomplished by rotating the beam generator 2, 202 that generates the multiple beams b1, b2 around a rotation axis A1 parallel to the multiple beams b1, b2, thereby adjusting the direction S1 in which the multiple beams b1, b2 are aligned.

[0087] According to this configuration, the direction S1 in which the beams b1 and b2 are aligned can be changed while maintaining the spacing between the beams b1 and b2. In other words, when the direction S1 in which the beams b1 and b2 are aligned is changed, the influence on conditions other than the direction in which the beams b1 and b2 are aligned can be reduced. As a result, when the direction S1 in which the beams b1 and b2 are aligned is changed, the influence on the scanning of the beams b1 and b2 can be reduced.

[0088] (Embodiment 7) The additive manufacturing apparatus 100, 200 comprises a beam generator 2, 202 that generates multiple beams b1, b2, a platform 11 that supports a powder bed 19 composed of raw material powder, a common scanner 4 that scans the multiple beams b1, b2 from the beam generator 2, 202 onto the powder bed 19, and a control device 5 that controls the beam generator 2, 202 and the scanner 4, wherein the beam generator 2, 202 is configured to be able to change the arrangement direction S1 of the multiple beams b1, b2 upstream of the scanner 4, and the control device 5 adjusts the arrangement direction S2 of the multiple irradiation points p1, p2 of the multiple beams b1, b2 on the powder bed 19 by adjusting the arrangement direction S1 of the multiple beams b1, b2 in conjunction with the scanning of the multiple beams b1, b2 by the scanner 4.

[0089] According to this configuration, the direction S2 in which the multiple irradiation points p1, p2 of the multiple beams b1, b2 on the powder bed 19 are arranged can be flexibly changed according to the scanning direction T of the multiple beams b1, b2. This allows for relatively free object formation. At this time, the direction S1 in which the multiple beams b1, b2 are arranged is adjusted upstream of the scanner 4, and the multiple beams b1, b2 whose arrangement direction S1 has been adjusted are scanned by the common scanner 4. This reduces the impact of scanning by the scanner 4 on the adjustment accuracy of the direction S2 in which the multiple irradiation points p1, p2 are arranged, and as a result, the adjustment accuracy of the direction S2 in which the multiple irradiation points p1, p2 are arranged can be improved.

[0090] (Embodiment 8) In the additive manufacturing apparatus 100, 200 described in any one of embodiments 1 to 7, the control device 5 adjusts the direction S1 in which the multiple beams b1, b2 are arranged in conjunction with the scanner 4 so that the angle α of the direction S2 in which the multiple irradiation points p1, p2 are arranged relative to the scanning direction T of the multiple beams b1, b2 is constant.

[0091] This configuration allows the spacing between the linear objects a1 and a2 formed by the multiple beams b1 and b2 to be kept constant. For example, multiple parallel linear objects a1 and a2 having complex shapes such as curved or bent shapes can be simultaneously formed by the multiple beams b1 and b2.

[0092] (Aspect 9) In the additive manufacturing apparatus 100, 200 described in any one of aspects 1 to 8, the control device 5 adjusts the direction S1 in which the multiple beams b1, b2 are arranged in conjunction with the scanner 4 so that the angle α of the direction S2 in which the multiple irradiation points p1, p2 are arranged relative to the scanning direction T of the multiple beams b1, b2 is perpendicular.

[0093] According to this configuration, the distance between the plurality of linear objects a1 and a2 formed by the plurality of beams b1 and b2 can be made relatively wide.

[0094] (Aspect 10) In the additive manufacturing apparatus 100, 200 described in any one of aspects 1 to 9, the control device 5 adjusts the direction S1 in which the multiple beams b1, b2 are arranged in conjunction with the scanner 4 so that one of the multiple irradiation points p1, p2 passes along the trajectory passed by the other of the multiple irradiation points p1, p2.

[0095] According to this configuration, the multiple linear objects a1, a2 formed by the multiple beams b1, b2 can be overlapped without changing the spacing between the multiple beams b1, b2. Furthermore, by adjusting the angle α of the direction S2 in which the multiple irradiation points p1, p2 are arranged with respect to the scanning direction T within a range where one of the multiple irradiation points p1, p2 maintains a state in which the other of the multiple irradiation points p1, p2 passes along the trajectory that the other of the multiple irradiation points p1, p2 passed, the thickness of the single linear object formed by the overlapping of the multiple linear objects a1, a2 can be adjusted.

[0096] (Embodiment 11) In the additive manufacturing apparatus 100, 200 described in any one of embodiments 1 to 10, a gas flow of inert gas is generated along the surface of the powder bed 19, and the control device 5 adjusts the direction S1 in which the multiple beams b1, b2 are arranged in conjunction with the scanner 4 so that, when the scanning direction T of the multiple beams b1, b2 intersects with the flow direction F of the inert gas, the irradiation point p1, p2 located downstream of the flow direction F precedes the irradiation point located upstream of the flow direction F in the scanning direction T.

[0097] According to this configuration, the influence of sputtering and the like caused by irradiation of a preceding beam in the scanning direction T on the formation of an object by a subsequent beam in the scanning direction T can be reduced.

[0098] (Aspect 12) In the additive manufacturing apparatus 100, 200 described in any one of aspects 1 to 11, the beam generator 2, 202 is configured to be rotatable around a rotation axis A1 parallel to the multiple beams b1, b2 emitted from the beam generator 2, 202, and the direction S1 in which the multiple beams b1, b2 are arranged is changed by rotating around the rotation axis A1.

[0099] According to this configuration, the direction S1 in which the beams b1 and b2 are aligned can be changed while maintaining the spacing between the beams b1 and b2. In other words, when changing the direction S1 in which the beams b1 and b2 are aligned, it is possible to reduce the impact on conditions other than the direction S1 in which the beams b1 and b2 are aligned. As a result, when changing the direction S1 in which the beams b1 and b2 are aligned, it is possible to reduce the impact on the scanning of the beams b1 and b2. [Explanation of symbols]

[0100] 100,200 Additive Manufacturing Equipment 11 Platform 19 Powder bed 2,202 Beam Generator 4. Scanner 5. Control device b1 First beam b2 Second beam p1 1st irradiation point p2 2nd irradiation point A1 rotation axis F Flow direction S1 Direction of multiple beams S2 Direction of multiple irradiation points α Angle of the direction in which multiple irradiation points are aligned relative to the scanning direction of multiple beams

Claims

1. generating a plurality of beams; scanning the plurality of beams over the powder bed with a common scanner to solidify the raw powder in the powder bed; and adjusting the alignment direction of the multiple beams upstream of the scanner in conjunction with the scanning of the multiple beams, thereby adjusting the alignment direction of the multiple irradiation points of the multiple beams on the powder bed.

2. 10. The additive manufacturing method of claim 1, In adjusting the direction in which the multiple beams are aligned, the direction in which the multiple beams are aligned is adjusted in conjunction with the scanning of the multiple beams so that the angle of the direction in which the multiple irradiation points are aligned relative to the scanning direction of the multiple beams is constant. An additive manufacturing method.

3. 3. The additive manufacturing method of claim 2, In adjusting the direction in which the multiple beams are aligned, the direction in which the multiple beams are aligned is adjusted in conjunction with the scanning of the multiple beams so that the angle of the direction in which the multiple irradiation points are aligned relative to the scanning direction of the multiple beams is perpendicular. An additive manufacturing method.

4. 10. The additive manufacturing method of claim 1, In adjusting the direction in which the multiple beams are aligned, the direction in which the multiple beams are aligned is adjusted in conjunction with the scanning of the multiple beams so that one of the multiple irradiation points passes along the trajectory that the other of the multiple irradiation points passed through.

5. 10. The additive manufacturing method of claim 1, generating a flow of inert gas along the surface of the powder bed; In adjusting the direction in which the multiple beams are aligned, when the scanning direction of the multiple beams intersects with the flow direction of the inert gas, the direction in which the multiple beams are aligned is adjusted in conjunction with the scanning of the multiple beams so that the irradiation point located downstream in the flow direction among the multiple irradiation points precedes the irradiation point located upstream in the flow direction in the scanning direction. An additive manufacturing method.

6. 10. The additive manufacturing method of claim 1, An additive manufacturing method in which, in adjusting the alignment direction of the multiple beams, the alignment direction of the multiple beams is adjusted by rotating a beam generator that generates the multiple beams around a rotation axis parallel to the multiple beams.

7. a beam generator for generating a plurality of beams; a platform supporting a powder bed formed by raw material powder; a common scanner for scanning the multiple beams from the beam generators onto the powder bed; a control device for controlling the beam generator and the scanner, the beam generator is configured to be able to change the direction in which the plurality of beams are arranged on the upstream side of the scanner; The control device adjusts the alignment direction of the multiple beams in conjunction with the scanning of the multiple beams by the scanner, thereby adjusting the alignment direction of the multiple irradiation points of the multiple beams on the powder bed.

8. 8. The additive manufacturing apparatus of claim 7, The control device adjusts the direction in which the multiple beams are arranged in conjunction with the scanner so that the angle of the direction in which the multiple irradiation points are arranged relative to the scanning direction of the multiple beams is constant.

9. 9. The additive manufacturing apparatus of claim 8, The control device adjusts the direction in which the multiple beams are arranged in conjunction with the scanner so that the angle of the direction in which the multiple irradiation points are arranged relative to the scanning direction of the multiple beams is perpendicular.

10. 8. The additive manufacturing apparatus of claim 7, The control device is an additive manufacturing device that adjusts the direction in which the multiple beams are arranged in conjunction with the scanner so that one of the multiple irradiation points passes along the trajectory that the other of the multiple irradiation points passed through.

11. 8. The additive manufacturing apparatus of claim 7, a flow of inert gas along the surface of the powder bed is generated; The control device adjusts the direction in which the multiple beams are arranged in conjunction with the scanner so that, when the scanning direction of the multiple beams intersects the flow direction of the inert gas, the irradiation point among the multiple irradiation points located downstream in the flow direction precedes the irradiation point located upstream in the flow direction in the scanning direction.

12. 8. The additive manufacturing apparatus of claim 7, The beam generator is configured to be rotatable around a rotation axis parallel to the multiple beams emitted from the beam generator, and an additive manufacturing device that changes the arrangement direction of the multiple beams by rotating around the rotation axis.

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