Model generation method, lamination molding method, model generation device, lamination molding device, and lamination molding system

Abstract

This model generation method includes: a prototype molding measurement step in which a prototype molding measurement unit (131) measures a j-th bead width, which is the width of a j-th bead, and a j-th molded article height, which is the molded article height after lamination-molding the j-th bead, by supplying a molding material, supplying a heating beam for heating to a processing region to melt the molding material, and performing prototype-molding under each processing condition from i=1 to k such that the j-th bead lamination-molded under an i-th processing condition is sequentially lamination-molded on a j-1st bead lamination-molded under an i-th processing condition, from a first stage to an n-th stage while counting, from a low layer, the lamination molding for lamination-molding the bead, which is the molding material in a molten state accumulated in the processing region, and the j-th bead width and the j-th molded article height are stored as measurement data in association with the i-th processing condition; and a model generation step in which a model generation unit (132) generates, on the basis of the measurement data, at least a model indicating the relationship between the i-th processing condition, the j-th bead width, and the j-th molded article height as the model of the lamination molding.

Description

Model generation method, additive manufacturing method, model generation device, additive manufacturing device, and additive manufacturing system

[0001] The present disclosure relates to a model generation method, an additive manufacturing method, a model generation device, an additive manufacturing device, and an additive manufacturing system for generating a model used in additive manufacturing.

[0002] Conventionally, metal additive manufacturing (AM) uses a high-temperature heat source to melt the material. Therefore, depending on the manufacturing method, an effective technique is to monitor and manage the interpass temperature, which is the temperature at the end of each layer after AM. This controls the bead shape to a value close to a target value. For example, Patent Literature 1 (JP-A-2005-102626) discloses a method for manufacturing an additively manufactured object with high precision. The method integrates measurement results obtained from a measuring device with a shape index extracted from a trajectory plan to obtain a more accurate shape index and update the trajectory plan, or repeatedly stacks weld beads while constantly managing the shape index. The method for manufacturing an additively manufactured object described in Patent Literature 1 involves repeatedly stacking weld beads, which are formed by melting and solidifying a filler material using a manufacturing device, based on a predetermined trajectory plan.

[0003] JP 2023-105801 A

[0004] However, with the above-described conventional technology, because the inter-pass temperature is closely related to the state of heat accumulation in the additive manufacturing object, it may be impossible to adequately control the bead shape based on the inter-pass temperature unless the additive manufacturing process has progressed to a certain extent and a certain amount of heat has accumulated in the additive manufacturing object. For example, in additive manufacturing of lower-layer portions of an additive manufacturing object without heat accumulation, the heat dissipation rate varies significantly from layer to layer depending on the size of the base portion, the size of the additive manufacturing object, and the amount of additive manufacturing. This means that the optimal inter-pass temperature may change for each shape or layer, or may be impossible to calculate. This makes it difficult to control the bead shape, potentially resulting in a decrease in the accuracy of the additive manufacturing process. Furthermore, because bead shape control as in the above-described conventional technology presupposes shape improvement by changing the path, manufacturing conditions, etc. in subsequent layers, the accuracy of the bead shape in those areas cannot be improved and remains low. Therefore, in lower layers where the heat dissipation rate varies significantly from layer to layer, subsequent layers may be affected by the low accuracy of the previous layers. Here, the term "layered object" refers to the combination of the workpiece at the start of modeling and the modeling material layered on top of it, so the layered object at the start of modeling is identical to the workpiece at the start of modeling.

[0005] The present disclosure has been made in consideration of the above, and aims to provide a model generation method capable of generating a model used in additive manufacturing that can improve the accuracy of additive manufacturing in low layers.

[0006] In order to solve the above-mentioned problems and achieve the object, the model generation method of the present disclosure is a method for manufacturing a prototype object, in which i is an integer of 1 or more, n, j, and k are integers of 2 or more, a prototype manufacturing measurement unit supplies a manufacturing material, supplies a heating beam for heating to a processing area to melt the manufacturing material, and additively manufactures beads, which are the molten manufacturing material deposited in the processing area, from the first to nth stages counting from the bottom, a j-th bead, which is an additively manufactured bead under the i-th processing conditions, a j-1-th bead, which is an additively manufactured bead under the i-th processing conditions, and a j-2-th bead, which is an additively manufactured bead under the i-th processing conditions. and a prototype manufacturing measurement step in which prototypes are manufactured under each processing condition from i=1 to i=k so that the prototypes are sequentially manufactured on top of each other by additive manufacturing, and the jth bead width, which is the width of the jth bead, and the jth object height, which is the height of the object manufactured after additive manufacturing of the jth bead, are measured and stored as measurement data in association with the ith processing condition; and a model generation step in which a model generation unit generates, based on the measurement data, a model that indicates at least the relationship between the ith processing condition, the jth bead width, and the jth object height as a model for additive manufacturing.

[0007] The model generation method of the present disclosure has the effect of being able to generate a model to be used in additive manufacturing that can improve the accuracy of additive manufacturing in low layers.

[0008] FIG. 1 is a diagram showing an example of the configuration of an additive manufacturing system including an additive manufacturing apparatus according to embodiment 1; FIG. 2 is a block diagram showing an example of the configuration of a model generating apparatus according to embodiment 1; FIG. 3 is a diagram showing an example of the relationship between laser output and bead width when the laser output is changed in the prototype manufacturing measurement unit of the model generating apparatus according to embodiment 1; Figure showing an example of the configuration of a processing circuit when realized by dedicated hardware. Figure showing an example of control of bead height by a numerical control device provided in an additive manufacturing device according to embodiment 3. Figure showing a four-branch pipe as an example of an actual object to be additively manufactured in an additive manufacturing device according to embodiment 4. Figure showing an example in which the average bead temperature logs of each layer in prototype manufacturing at different heating beam outputs obtained by a model generation device according to embodiment 4 are plotted for each height of the object. Figure showing an example of measurement of base material temperature during prototype manufacturing in a model generation device according to embodiment 4. Figure showing an example of line manufacturing and point manufacturing performed by a numerical control device provided in an additive manufacturing device according to embodiment 5. Figure showing how the inter-pass temperature of an additive manufacturing object is measured in an additive manufacturing device according to embodiment 6.

[0009] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A model generation method, an additive manufacturing method, a model generation device, an additive manufacturing device, and an additive manufacturing system according to embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings.

[0010] First Embodiment. FIG. 1 is a diagram showing an example of the configuration of an additive manufacturing system 200 including an additive manufacturing apparatus 100 according to a first embodiment. The additive manufacturing system 200 includes the additive manufacturing apparatus 100 and a processing program generating device 110. The additive manufacturing apparatus 100 includes a control device 1. The control device 1 includes a numerical control device 120 and a model generating device 130. The additive manufacturing apparatus 100 is an apparatus that performs additive manufacturing by having the numerical control device 120 control the operation of the additive manufacturing apparatus 100 using a model generated by the model generating device 130. The processing program generating device 110 provides the additive manufacturing apparatus 100 with a processing program used in additive manufacturing of an additively manufactured object. The processing program generating device 110 is intended to be, for example, a computer-aided manufacturing (CAM) system, but is not limited thereto. The additive manufacturing apparatus 100 and the processing program generating device 110 may be directly connected via a wire or the like, or may be connected via a network such as the Internet. The additive manufacturing apparatus 100 is assumed to perform additive manufacturing using, for example, a wire DED (Directed Energy Deposition) method, but is not limited to this.

[0011] In the additive manufacturing apparatus 100, the modeling material supply device 19 supplies the modeling material 5 to the modeling point 26. Specifically, in the modeling material supply device 19, the spool drive device 4 supplies the modeling material 5 wound around a wire spool 6 to the modeling point 26 via the wire nozzle 12. The modeling material 5 is, for example, a columnar material such as a wire. Furthermore, the heat source supply device 2, such as a laser, supplies a heat source 24, such as a laser, to the modeling point 26 via a heat source path 3, such as a fiber, the processing head 10, the beam nozzle 11, etc. As described above, the heat source 24 is assumed to be a laser or the like. Furthermore, the gas supply unit 7 supplies a shielding gas 25 to the modeling point 26 via a gas piping path 8, the processing head 10, the gas nozzle 13, etc. The position of the processing head 10 is controlled in three axial directions, i.e., the X-axis, the Y-axis, and the Z-axis, by the processing head drive unit 14. The base plate 17 serves as a base on which the additively manufactured object 18 is additively manufactured. That is, the layered object 18 is layer-by-layer manufactured on the base plate 17. The position of the layered object 18 on the base plate 17 is controlled in two axial directions, the A-axis and the C-axis, by a stage rotation mechanism 16 that drives the stage 15. The stage rotation mechanism 16 may have an axial configuration in two axial directions, the B-axis and the C-axis. The processing head 10 and the stage rotation mechanism 16 may also have other multi-axis structures. The temperature measurement unit 50 is, for example, a radiation thermometer, and measures the temperature of the manufacturing point 26 of the layered object 18.

[0012] In the additive manufacturing apparatus 100, the numerical control device 120 of the control device 1 controls the operations of the modeling material supply device 19, the heat source supply device 2, the gas supply unit 7, the processing head drive unit 14, the stage rotation mechanism 16, etc. during additive manufacturing of the additively manufactured object 18. In addition, the model generation device 130 of the control device 1 controls the operations of the modeling material supply device 19, the heat source supply device 2, the gas supply unit 7, the processing head drive unit 14, the stage rotation mechanism 16, etc. during prototype manufacturing, which will be described later. In the additive manufacturing system 200, the components other than the control device 1 are of a general configuration, so detailed description of the components other than the control device 1 will be omitted.

[0013] Generally, metal additive manufacturing (AM) uses a high-temperature heat source 24 to melt the build material 5. Therefore, depending on the manufacturing method, it is considered effective to use a manufacturing control technique that monitors and manages the inter-pass temperature to maintain a constant bead width. However, since the inter-pass temperature is closely related to the amount of heat stored in the additively manufactured object 18, the effectiveness of the manufacturing control based on the inter-pass temperature is not fully realized unless the AM process has progressed to a certain extent and the additively manufactured object 18 has accumulated heat. Based on the above, in the first embodiment, a method for achieving high-precision AM, i.e., AM with a constant bead width, even in the lower layers of the additively manufactured object 18 before heat accumulation, will be described. In the following description, the additively manufactured object 18 will sometimes be simply referred to as the "manufactured object," and the AM process will sometimes be simply referred to as "manufacturing."

[0014] First, the configuration and operation of the model generation device 130 will be described. The model generation device 130 performs the process of additive manufacturing up to n layers under constant processing conditions multiple times while changing the processing conditions, and generates a model to be used when the numerical control device 120 of the control device 1 performs additive manufacturing. Fig. 2 is a block diagram showing an example configuration of the model generation device 130 according to the first embodiment. The model generation device 130 includes a prototype manufacturing measurement unit 131 and a model generation unit 132.

[0015] The prototype manufacturing measurement unit 131 supplies the manufacturing material 5, supplies a heating beam to the processing area to melt the manufacturing material 5, and performs additive manufacturing of beads, which are the molten manufacturing material 5 deposited in the processing area, from the first to nth stages counting from the lowest layer, under processing conditions i=1 to i=k, such that the jth bead, which is the bead manufactured under the i-th processing condition, is additively manufactured on top of the j-1st bead, which is the bead manufactured under the i-th processing condition. The prototype manufacturing measurement unit 131 measures the jth bead width, which is the width of the jth bead, and the jth object height, which is the height of the object manufactured after additive manufacturing of the jth bead, using a direct-above camera, laser ranging, etc., and stores the measurement data in association with the i-th processing condition. Note that i is an integer equal to or greater than 1, and n, j, and k are integers equal to or greater than 2. Furthermore, n is a number smaller than the number of stages of additive manufacturing required to complete the additively manufactured object 18. The range of the processing area is the same as the range of the aforementioned manufacturing point 26. In addition to the above items, the prototype manufacturing measurement unit 131 may measure, for example, the bead temperature, the temperature of the base material from which the additively manufactured object 18 is manufactured, and the color of the processing area during processing. In addition to the laser output, the prototype manufacturing measurement unit 131 may also control the supply speed of the modeling material 5 from the modeling material supply device 19, the movement speed of the processing head drive unit 14 and the stage rotation mechanism 16, the current for heating the modeling material 5, the flow rate of the shielding gas 25, and the like. The prototype manufacturing measurement unit 131 may change the processing conditions for prototype manufacturing automatically or in response to input from an operator or the like. The model generation device 130 may also include a memory unit (not shown) for storing measurement data. The processing conditions include a heat source command, a modeling material supply amount, and a movement speed of the processing head drive unit 14 and the stage rotation mechanism 16. The processing conditions may additionally include a rest time for cooling in each layer, a modeling material supply angle, and the like.

[0016] The model generation unit 132 generates, as an additive manufacturing model, a model that indicates at least the relationship between the ith processing condition, the jth bead width, and the jth object height, based on the measurement data. For example, the model generation unit 132 creates a model of the lower layer portion that is less susceptible to the influence of heat accumulation, such as a relational expression between the laser output, the bead width, and the object height, from data obtained by, for example, performing prototype manufacturing multiple times using the prototype manufacturing measurement unit 131 while changing the laser output conditions for several lower layer portions of the reference shape. In addition to the above items, the model generation unit 132 may also include, for example, some of the bead temperature, the temperature of the base material from which the additive manufacturing object 18 is additively manufactured, the color of the processed area during processing, and other items measured during prototype manufacturing by the prototype manufacturing measurement unit 131, in the aforementioned relational expression. Furthermore, in addition to the laser output, the model generation unit 132 may include some of the following items in the above-mentioned relational expression if they can be controlled by the prototype manufacturing measurement unit 131: the supply speed of the modeling material 5 from the modeling material supply device 19, the movement speed of the processing head drive unit 14 and the stage rotation mechanism 16, the current for heating the modeling material 5, and the flow rate of the shielding gas 25. The reference shape is not actually additively manufactured by the additive manufacturing device 100, but is a simple shape such as a straight line, an L-shape, or a curved line with a specified radius. The reference shape may be one or more of the following: a straight line, an L-shape, a curved line with a specified radius, etc. The model generation unit 132 may use machine learning, AI (artificial intelligence), etc. when generating the model.

[0017] The numerical control device 120 can perform additive manufacturing with a constant bead width by gradually reducing the laser output using a feedforward method based on the model generated by the model generation unit 132. Wire-DED metal additive manufacturing generally has low sensitivity to changes in bead width when the laser output, wire supply, etc. are changed, i.e., the time constant is long. Therefore, the numerical control device 120 can achieve higher accuracy in additive manufacturing by attempting feedforward additive manufacturing until heat is accumulated.

[0018] FIG. 3 shows an example of the relationship between laser power and bead width when the laser power is changed in the prototype manufacturing measurement unit 131 of the model generating device 130 according to the first embodiment. In FIG. 3, the horizontal axis represents the height of the object, and the vertical axis represents the bead width. The graph in FIG. 3 shows the change for each laser power, with the lower graph representing the lower laser power and the higher laser power representing the upper graph. The reason why the change in bead width at each laser power does not change linearly is because the amount of heat escape from the layered object 18 to the base plate 17 decreases nonlinearly as the height of the object increases. For example, when performing layered manufacturing with a bead width of 3 mm, as indicated by the dotted arrow in FIG. 3, the numerical control device 120 initially needs to use a high laser power, but can change to a lower laser power as the height of the object increases. From the relationship in FIG. 3, the optimal value of laser power can be determined according to the desired bead width and height of the object.

[0019] The prototype-forming measuring unit 131 of the model generating device 130 may actually measure and obtain all of the relationships between the height of the object and the bead width for each laser output power shown in Fig. 3 , or may obtain the relationships by using interpolation such as extrapolation or interpolation. Furthermore, with regard to the relationships between the height of the object and the bead width for each laser output power shown in Fig. 3 , the prototype-forming measuring unit 131 of the model generating device 130 may perform precise measurement for each laser output power when the height of the object is 40 mm or less, and may widen the measurement interval or use extrapolation when the height of the object exceeds 40 mm, for example.

[0020] Although the case where the control device 1 of the additive manufacturing apparatus 100 includes the model generation device 130 has been described, the present invention is not limited to this. In the model generation device 130, for example, the prototype manufacturing measuring unit 131 needs to perform prototype manufacturing, measurement, etc. in the additive manufacturing apparatus 100, but the model generation unit 132 may be located outside the additive manufacturing apparatus 100 as long as it can obtain measurement data from the prototype manufacturing measuring unit 131. The model generation unit 132 may obtain the measurement data from the prototype manufacturing measuring unit 131 via wireless communication, wired communication, or via a storage medium.

[0021] 4 is a flowchart showing the operation of the model generating device 130 according to the first embodiment. In the model generating device 130, the prototype forming measuring unit 131 performs prototype forming by changing the processing conditions (step S11). The prototype forming measuring unit 131 measures the bead width, the height of the object, etc. under each processing condition (step S12) and stores the measured data in association with the processing conditions (step S13). The model generating unit 132 uses the measured data to generate an additive manufacturing model to be used in the additive manufacturing device 100 (step S14).

[0022] Next, the configuration and operation of the numerical control device 120 that performs additive manufacturing using the model generated by the model generation device 130 will be described. FIG. 5 is a block diagram showing an example configuration of the numerical control device 120 included in the additive manufacturing device 100 according to the first embodiment. Note that FIG. 5 omits the illustration of components other than the control device 1 included in the additive manufacturing device 100. Also, FIG. 5 omits the illustration of the model generation device 130 included in the control device 1. The numerical control device 120 includes an additive manufacturing unit 121. In other words, it can be said that the additive manufacturing device 100 includes the additive manufacturing unit 121. The additive manufacturing unit 121 performs additive manufacturing under processing conditions determined based on the model generated by the model generation device 130. By using the relationship between laser output and bead width shown in FIG. 3, the additive manufacturing unit 121 can perform control such that the laser output is changed to a lower value as the height of the object increases.

[0023] 6 is a flowchart showing the operation of the numerical control device 120 included in the additive manufacturing apparatus 100 according to the first embodiment. In the numerical control device 120, the additive manufacturing unit 121 acquires a model from the model generation device 130 (step S21). When the model generation device 130 is located within the control device 1 as shown in FIG. 1 , the additive manufacturing unit 121 can easily acquire a model from the model generation unit 132. However, when the model generation unit 132 of the model generation device 130 is located outside the additive manufacturing apparatus 100 as described above, the additive manufacturing unit 121 may acquire the model from the model generation unit 132 via wireless communication, wired communication, or via a storage medium. The additive manufacturing unit 121 performs additive manufacturing using the acquired model (step S22).

[0024] Next, a hardware configuration of the model generating device 130 according to the first embodiment will be described. In the model generating device 130, the prototype forming measurement unit 131 and the model generating unit 132 are realized by processing circuits. The processing circuit may be a memory that stores a program and a processor that executes the program stored in the memory, or may be dedicated hardware. The processing circuit is also called a control circuit.

[0025] FIG. 7 is a diagram illustrating an example of the configuration of a processing circuit 90 that implements the model generation device 130 according to the first embodiment when the processing circuit is implemented by a processor 91 and a memory 92. The processing circuit 90 illustrated in FIG. 7 is a control circuit and includes a processor 91 and a memory 92. When the processing circuit 90 is configured with the processor 91 and the memory 92, each function of the processing circuit 90 is implemented by software, firmware, or a combination of software and firmware. The software or firmware is written as a program and stored in the memory 92. The processor 91 reads and executes the program stored in the memory 92 to implement each function of the processing circuit 90. That is, the processing circuit 90 includes the memory 92 for storing a program that results in the execution of the processing of the model generation device 130. This program can also be said to be a program that causes the model generation device 130 to execute each function implemented by the processing circuit 90. This program may be provided by a storage medium on which the program is stored, or by other means such as a communication medium.

[0026] Here, the processor 91 is, for example, a CPU (Central Processing Unit), a processing device, an arithmetic unit, a microprocessor, a microcomputer, or a DSP (Digital Signal Processor), etc. The memory 92 is, for example, a non-volatile or volatile semiconductor memory such as a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory, an EPROM (Erasable Programmable ROM), or an EEPROM (Electrically EPROM), a magnetic disk, a flexible disk, an optical disk, a compact disk, a minidisk, or a DVD (Digital Versatile Disc).

[0027] FIG. 8 is a diagram illustrating an example of the configuration of the processing circuitry 93 that implements the model generating device 130 according to the first embodiment when the processing circuitry is implemented by dedicated hardware. The processing circuitry 93 illustrated in FIG. 8 corresponds to, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), or a combination thereof. The processing circuitry 93 may be partially implemented by dedicated hardware and partially implemented by software or firmware. In this way, the processing circuitry 93 can implement each of the above-described functions by dedicated hardware, software, firmware, or a combination thereof.

[0028] The hardware configuration of the model generating device 130 has been described above, but the hardware configuration of the numerical control device 120 included in the additive manufacturing device 100 is also similar. In the numerical control device 120, the additive manufacturing unit 121 is realized by a processing circuit. The processing circuit may be a memory that stores a program and a processor that executes the program stored in the memory, or it may be dedicated hardware. The processing circuit is also called a control circuit.

[0029] As described above, according to this embodiment, the model generation device 130 performs prototype manufacturing of the lower layer portion multiple times under various processing conditions, measures the bead width, the height of the object, and the like under each processing condition, associates the measured data with the processing conditions, and uses the measured data to generate an additive manufacturing model to be used in the additive manufacturing device 100. The additive manufacturing unit 121 of the numerical control device 120 performs additive manufacturing using the model generated by the model generation device 130. In this way, the model generation device 130 can generate a model to be used in additive manufacturing that can improve the accuracy of additive manufacturing of the lower layer portion. As a result, by using the model generated by the model generation device 130, the additive manufacturing unit 121 of the numerical control device 120 can achieve high-precision additive manufacturing even when additive manufacturing the lower layer portion of the additive manufacturing object 18 before heat storage.

[0030] Embodiment 2 In Embodiment 1, the prototype manufacturing measurement unit 131 of the model generating device 130 performs additive manufacturing from the first stage to the nth stage under one processing condition as prototype manufacturing, and performs this process k patterns. In Embodiment 2, a case will be described in which prototype manufacturing by the prototype manufacturing measurement unit 131 of the model generating device 130 is simplified.

[0031] In the second embodiment, the configurations of the additive manufacturing system 200, the model generating device 130, and the numerical control device 120 are similar to the configurations of the additive manufacturing system 200, the model generating device 130, and the numerical control device 120 in the first embodiment.

[0032] In the second embodiment, the prototype manufacturing measuring unit 131 in the model generating device 130 supplies the manufacturing material 5, supplies a heating beam to the processing area to melt the manufacturing material 5, and performs additive manufacturing of beads, which are the molten manufacturing material 5 deposited in the processing area, from the first to nth stages counting from the lowest layer, so that the i-th bead, which is manufactured under the i-th processing conditions, is additively manufactured on the i-1st bead, which is manufactured under the i-1st processing conditions, or on the base plate 17. The prototype manufacturing measuring unit 131 measures the i-th bead width, which is the width of the i-th bead, and the i-th object height, which is the height of the object manufactured after additive manufacturing of the i-th bead, and stores the measured data in association with the i-th processing condition. Note that i is an integer of 1 or greater, and n is an integer of 2 or greater. When i is 1, the first bead is additively manufactured on the zeroth bead. Here, the zeroth bead refers to the base plate 17. Since the base plate 17 is not additively manufactured, the zeroth processing condition does not exist. Therefore, the zeroth processing condition when i = 1 is excluded from the aforementioned (i-1)th processing condition. Furthermore, n is a number smaller than the number of additive manufacturing stages required to complete the additively manufactured object 18. The range of the processing area is the same as the range of the aforementioned manufacturing point 26. As in the first embodiment, the prototype manufacturing measuring unit 131 may measure the bead temperature, the temperature of the base material from which the additively manufactured object 18 is manufactured, the color of the processing area during processing, and the like. As in the first embodiment, the prototype manufacturing measuring unit 131 may also control the supply speed of the modeling material 5 from the modeling material supply device 19, the movement speed of the processing head driving unit 14 and the stage rotation mechanism 16, the current for heating the modeling material 5, the flow rate of the shielding gas 25, and the like. The prototype forming measurement unit 131 may change the processing conditions for prototype forming automatically or may change the processing conditions in response to input from an operator, etc. The model generating device 130 may include a storage unit (not shown) for storing measurement data.

[0033] The model generation unit 132 generates, as an additive manufacturing model, a model that indicates at least the relationship between the ith processing condition, the ith bead width, and the ith object height, based on the measurement data. For example, the model generation unit 132 creates a model of the lower portion that is less susceptible to heat accumulation, for example, a relational expression between the laser output, the bead width, and the object height, based on data obtained by performing prototype manufacturing only once on the lower portion of the reference shape using the prototype manufacturing measurement unit 131. As in the first embodiment, the model generation unit 132 may include items other than those described above in the relational expression, depending on the measurement items and control details of the prototype manufacturing measurement unit 131. The reference shape is the same as the reference shape described in the first embodiment. The model generation unit 132 may use machine learning, AI, or the like when generating the model.

[0034] The first embodiment is useful, for example, when a new additive manufacturing apparatus 100 is introduced. On the other hand, when some of the components constituting the additive manufacturing apparatus 100 are changed or the layout of some of the components is changed, it may be possible to predict the optimal additive manufacturing processing conditions to a certain extent. In the second embodiment, the model generation device 130 performs the above-described operations in such a situation, thereby generating a model more efficiently than in the first embodiment. That is, the model generation device 130 can generate a rough model by prototype manufacturing targeting a single low-layer batch. The operation of the numerical control device 120 is the same as in the first embodiment. That is, the additive manufacturing unit 121 performs additive manufacturing under processing conditions determined based on the model generated by the model generation device 130.

[0035] As described above, according to this embodiment, the model generation device 130 performs prototype modeling by changing the processing conditions for each layer, measures the bead width, the height of the object, and the like, associates the measured data with the processing conditions, and stores the measured data. The measurement data is then used to generate a model for additive manufacturing to be used in the additive manufacturing device 100. This allows the model generation device 130 to efficiently generate a model when it is not necessary to change the processing conditions multiple times, as in the first embodiment. While the description has been given of a case in which the model generation device 130 changes the processing conditions for each layer, this is not limiting. The model generation device 130 can also perform prototype modeling for two or more consecutive layers using the same processing conditions.

[0036] Embodiment 3 In additive manufacturing, the bead width of the additively manufactured object 18 can be adjusted with high precision by changing the laser output, as described in Embodiments 1 and 2. However, stable additive manufacturing cannot be achieved with respect to the bead height unless the supply amount of the manufacturing material 5 is optimally changed according to the actual height of the additively manufactured object 18 at each manufacturing position. In Embodiment 3, a case will be described in which high-precision additive manufacturing of both the bead width and bead height of the additively manufactured object 18 is achieved.

[0037] In the third embodiment, the configurations of the additive manufacturing system 200, the model generating device 130, and the numerical control device 120 are similar to the configurations of the additive manufacturing system 200, the model generating device 130, and the numerical control device 120 in the first embodiment.

[0038] In the third embodiment, the additive manufacturing unit 121 in the numerical control device 120 performs additive manufacturing across multiple layers, where the pth bead from p = 1 to m overlaps the p-1th bead or the base plate 17, and measures the pth bead height, which is the height of the pth bead from p = 1 to m. The additive manufacturing unit 121 uses the measurement result of the p-1th bead height and controls the processing conditions, including the amount of modeling material supplied, during additive manufacturing of the pth bead height based on the measurement result of the p-1th bead height. Note that m is an integer of 2 or greater. m is the number of layers required for additive manufacturing of the additively manufactured object 18, and may be greater or smaller than n depending on the size of the additively manufactured object 18. Note that when p = 1, the first bead is additively manufactured on the 0th bead, but here, the 0th bead is assumed to be on the base plate 17.

[0039] FIG. 9 is a diagram showing an example of bead height control by the numerical control device 120 included in the additive manufacturing apparatus 100 according to the third embodiment. FIG. 9 shows the area around the manufacturing point 26 in the additive manufacturing apparatus 100 shown in FIG. 1 , with a height sensor 51 added to the additive manufacturing apparatus 100 for measuring the bead height. Note that FIG. 9 shows the flow of additive manufacturing, and the position of the processing head 10 and other components relative to the additive manufacturing object 18 is changed by the additive manufacturing unit 121 controlling the processing head driver 14 or the stage rotation mechanism 16. In the numerical control device 120, the additive manufacturing unit 121 compares the bead height obtained from the height sensor 51 with the reference value of the bead height for each layer as shown in FIG. 9 . The additive manufacturing unit 121 controls the supply by the manufacturing material supply device 19 so that more manufacturing material 5 is supplied at locations where the bead height is lower than the reference value than at locations where the bead height is the reference value, and controls the supply by the manufacturing material supply device 19 so that less manufacturing material 5 is supplied at locations where the bead height is higher than the reference value than at locations where the bead height is the reference value.

[0040] In the above example, the additive manufacturing unit 121 attempts to flatten the bead height using the measurement result of the bead height during additive manufacturing of the previous layer, i.e., the p-1th bead height, but this is not limited to this. The additive manufacturing unit 121 may further use the measurement results of the first bead height to the p-2th bead height to control the processing conditions, including the amount of modeling material supplied, during additive manufacturing of the pth bead height based on the measurement results of the first bead height to the p-1th bead height together with the measurement result of the p-1th bead height.

[0041] In this way, the additive manufacturing unit 121 can control the supply of modeling material by the modeling material supply device 19 so that the bead height is equal to a reference value, using not only the bead height during additive manufacturing of the previous layer but also the bead height from the bead height during additive manufacturing of the first layer to the bead height during additive manufacturing of the previous layer. Comparing the former pattern described first with the latter pattern described next, the former pattern requires a smaller amount of memory for storing the bead height in the numerical control device 120, while the latter pattern requires a larger amount of memory for storing the bead height in the numerical control device 120. However, the latter pattern can better handle larger modeling failures, such as dents spanning multiple layers. Note that in the latter pattern, depending on the amount of memory available in the numerical control device 120, the additive manufacturing unit 121 can also store only the bead heights during additive manufacturing of the most recent few layers, rather than all bead heights from the bead height during additive manufacturing of the first layer to the bead height during additive manufacturing of the previous layer.

[0042] As described above, according to this embodiment, the additive manufacturing unit 121 of the numerical control device 120, in addition to the control of embodiment 1 or 2, measures the bead height and adjusts the supply amount of the modeling material 5. This allows the additive manufacturing device 100 to maintain a constant bead width while suppressing unevenness in the bead height in the vertical direction. When the laser output of the additive manufacturing device 100 is changed during actual modeling, it is usually necessary to readjust the vertical Z-axis pitch, axial feed speed, etc. However, the control of this embodiment allows additive manufacturing without unevenness in the vertical direction without changing these. Furthermore, the control of this embodiment allows the additive manufacturing device 100 to avoid an increase in modeling time and the difficulty of adjusting modeling parameters.

[0043] Although the above description has been given taking as an example a case where the additive manufacturing unit 121 of the numerical control device 120 flattens the bead height, the present invention is not limited to this. For example, when additive manufacturing an additively manufactured object 18 that does not require strict additive manufacturing accuracy, the additive manufacturing unit 121 of the numerical control device 120 can also perform control to change the bead height so that the bead height falls within a certain range from a reference value.

[0044] Embodiment 4. In Embodiments 1 to 3, the purpose was to generate a model that would serve as base data for the additive manufacturing device 100, and therefore the shape of the target additively manufactured object 18 was assumed to be a simple shape, such as the reference shape described above. Therefore, when attempting to actually additively manufacture an additively manufactured object 18 with a complex shape, there is a possibility that a large difference will occur between the way heat escapes in the lower layers during additive manufacturing of the additively manufactured object 18 with a complex shape and the way heat escapes in the lower layers assumed in the model generated in Embodiment 1 or 2. In Embodiment 4, a case will be described in which additively manufactured an additively manufactured object 18 with a complex shape.

[0045] In the fourth embodiment, the configurations of the additive manufacturing system 200, the model generating device 130, and the numerical control device 120 are the same as those of the additive manufacturing system 200, the model generating device 130, and the numerical control device 120 in the first embodiment.

[0046] In the fourth embodiment, the model generated by the model generation unit 132 of the model generation device 130 in the first or second embodiment is referred to as the first model. It is also assumed that the model generation unit 132 of the model generation device 130 executes prototype modeling of a specified lower portion of the actual object to generate a second model of the actual object. The actual object is the layered object 18 having a complex shape as described above. The second model can be generated by the model generation unit 132 of the model generation device 130 in the same manner as the method for generating the first model in the first or second embodiment.

[0047] The additive manufacturing unit 121 of the numerical control device 120 uses the second model in additive manufacturing of the lower-layer portion of the actual object, and additive manufacturing of a higher-layer portion that is part of the actual object and is to be additively manufactured on top of the lower-layer portion after the lower-layer portion is formed, under processing conditions determined based on the first model. That is, the additive manufacturing unit 121 of the numerical control device 120 performs additive manufacturing of the lower-layer portion of the actual object using the second model obtained by prototype manufacturing of the lower-layer portion of the actual object, and performs additive manufacturing of the higher-layer portion of the actual object using the versatile first model generated in embodiment 1 or embodiment 2. For example, if the relationship shown in FIG. 3 was obtained when the first model was generated in embodiment 1 or embodiment 2, the additive manufacturing unit 121 of the numerical control device 120 can control the laser output, etc., based on the relationship shown in FIG. 3. The additive manufacturing unit 121 of the numerical control device 120 can estimate the bead width for each laser output by extrapolation, even for object heights exceeding 140 mm, which are not shown in Figure 3, and can therefore control the laser output, etc. based on the estimated relationship.

[0048] FIG. 10 is a diagram showing a four-branch pipe, which is an example of an actual object to be additively manufactured by the additive manufacturing apparatus 100 according to embodiment 4. In FIG. 10, the left side shows the entire four-branch pipe, and the right side shows a lower-layer portion of the four-branch pipe. For an actual object such as that shown in FIG. 10, i.e., an object in which the detailed heat transfer is difficult to determine, the prototype manufacturing measurement unit 131 of the model generation device 130 actually additively manufactures only the lower-layer portion under several processing conditions to obtain measurement data for model creation. The model generation unit 132 uses the measurement data obtained by the prototype manufacturing measurement unit 131 to generate a model of the actual object, i.e., a second model.

[0049] The model generation device 130 creates a more accurate low-layer model using measurement data obtained when the lower layer portion of the desired actual object is prototyped. The additive manufacturing unit 121 of the numerical control device 120 uses this low-layer model generated by the model generation device 130 to improve the accuracy of additive manufacturing when additively manufacturing the actual object.

[0050] Specifically, the prototype manufacturing measurement unit 131 of the model generation device 130 performs prototype manufacturing of the lower layer portion to obtain accurate measurement data on the relationship between the laser output, molten pool width, and the like with respect to the desired actual object. The lower layer portion depends on the size of the actual object, but can be defined as, for example, up to a height of 50 mm, or up to a height at which the impact of heat loss to the base material is minimized, but is not limited to these. The prototype manufacturing measurement unit 131 of the model generation device 130 performs prototype manufacturing k times in the method of embodiment 1 and once in the method of embodiment 2. This allows the model generation unit 132 of the model generation device 130 to generate a more accurate lower layer model.

[0051] The following three examples are likely to be the most likely methods for determining whether the impact of heat loss to the base material has been reduced, i.e., whether heat accumulation has stabilized. 1: Measuring the bead width, bead temperature, etc. with a radiation thermometer, etc. 2: Measuring the base material temperature with a thermocouple, etc. 3: Measuring the bead color. For example, with titanium, the color changes depending on the thickness of the oxide film, which reacts sensitively to the degree of heat accumulation.

[0052] 1: Bead Width and Bead Temperature: Even when additive manufacturing is performed under consistent processing conditions, bead widths tend to be small or variable in lower layers due to changes in heat dissipation. This is because heat dissipates easily to the base plate 17, stage 15, and other components during additive manufacturing near the base plate 17. The heat dissipation pattern also varies depending on the individual setup of the object, such as the size of the base plate 17 and the placement of insulating material between the base plate 17 and stage 15. As the manufacturing process progresses and the degree of heat accumulation near the processing area stabilizes, the bead width gradually becomes uniform. The bead width itself can be measured using image processing of information from an overhead camera or laser ranging, and the stabilization of heat accumulation can be determined from data from the overhead camera and laser ranging. Regarding bead temperature, measuring the bead temperature during additive manufacturing shows that the temperature gradually saturates as heat accumulation stabilizes. 11 is a diagram showing an example in which the average bead temperature logs of each layer in prototype printing at different heating beam outputs obtained by the model generating device 130 according to embodiment 4 are plotted for each height of the object. As shown in Fig. 11, when the height of the object reaches a certain height, the temperature changes almost completely regardless of the heating beam output, and becomes an approximately constant value according to the heating beam output.

[0053] 2: Base Material Temperature When the base material temperature is measured during additive manufacturing of the additively manufactured object 18, the temperature gradually saturates as heat accumulation becomes steady, similar to the bead temperature. Figure 12 is a diagram showing an example of measuring the base material temperature during prototype manufacturing using the model generation device 130 according to embodiment 4. The base material temperature can be measured using a thermocouple measuring instrument as shown in Figure 12, as well as a radiation thermometer. Note that in the example of Figure 12, the shape of the additively manufactured object 18 and the method of additive manufacturing of the additively manufactured object 18 are not particularly important.

[0054] As described above, according to this embodiment, the model generation device 130 uses measurement data obtained when a lower-layer portion of the desired actual object is prototyped to generate a second model, which is a more accurate lower-layer model that is more suitable for the desired actual object than the first model. The additive manufacturing unit 121 of the numerical control device 120 performs additive manufacturing of the lower-layer portion of the desired actual object using the second model generated by the model generation device 130, and performs additive manufacturing of the upper portion to be additively manufactured on top of the lower-layer portion of the desired actual object using the first model generated by the model generation device 130. This enables the additive manufacturing unit 121 of the numerical control device 120 to improve the accuracy of additive manufacturing when additively manufacturing a complex-shaped additively manufactured object 18.

[0055] Fifth Embodiment Additive manufacturing includes line manufacturing and point manufacturing. Line manufacturing has a fast manufacturing speed, but the accuracy of the additive manufacturing of the beginning and end portions of the bead may decrease due to thermal distortion caused by heat accumulation. In such cases, point manufacturing may be performed on the beginning and end portions of the bead to improve the accuracy of the beginning and end portions. However, if point manufacturing is performed continuously, the ends of the bead, especially the end portions, are prone to cracking due to heating. In the fifth embodiment, a method for improving such defects in point manufacturing will be described.

[0056] In the fifth embodiment, the configurations of the additive manufacturing system 200, the model generating device 130, and the numerical control device 120 are similar to the configurations of the additive manufacturing system 200, the model generating device 130, and the numerical control device 120 in the first embodiment.

[0057] 13A and 13B are diagrams illustrating examples of line shaping and point shaping performed by the numerical control device 120 included in the additive manufacturing device 100 according to the fifth embodiment. FIG. 13A illustrates a state in which the additive manufacturing unit 121 has performed line shaping, with the start and end portions of the line bead drooping. In such a case, the additive manufacturing unit 121 can improve the drooping of the start and end portions of the line bead by performing point shaping on the start and end portions as shown in FIG. 13B. However, as described above, if point shaping is performed continuously, the end of the bead is more likely to crack due to heating.

[0058] Therefore, in the fifth embodiment, the additive manufacturing unit 121 of the numerical control device 120 performs a first additive manufacturing process to additively manufacture a linear bead in the processing area by supplying the modeling material 5 and supplying the heat source 24 to the processing area to melt the modeling material 5. The additive manufacturing unit 121 also performs a second additive manufacturing process to additively manufacture point-like beads at the start and end portions until the height of the start and end portions is flat by measuring the height of the start and end portions of the bead, supplying a small amount of modeling material 5, and supplying the heat source 24 to the processing area for a short period of time to melt the supplied small amount of modeling material 5 in a point-like manner. The additive manufacturing unit 121 measures the inter-process temperature, which is the temperature of the entire object, each time the first additive manufacturing process is completed for a specified number of layers. If the inter-process temperature is equal to or lower than a specified temperature threshold, the additive manufacturing unit 121 performs the second additive manufacturing process without a cooling down time. If the inter-process temperature is higher than the temperature threshold, the additive manufacturing unit 121 performs the second additive manufacturing process after a downtime.

[0059] The inter-process temperature is the inter-pass temperature described above. The temperature threshold is a value that is set in advance depending on the type of modeling material 5 used. In this way, if the measured value of the inter-process temperature near the end is high when measuring the inter-process temperature, the additive manufacturing unit 121 provides a pause time so as not to continuously perform point modeling of the end portion. This allows the additive manufacturing unit 121 to prevent bead cracking and improve the accuracy of additive manufacturing of the additive manufacturing object 18. Note that if the measured value of the inter-process temperature near the end is high when measuring the inter-process temperature, the additive manufacturing unit 121 may provide a pause time and perform operations such as reducing the overall laser output or performing forced air cooling with nitrogen or the like during the pause time.

[0060] As described above, according to this embodiment, when linear shaping and point shaping are used in combination, the additive manufacturing unit 121 of the numerical control device 120 provides a rest period if the measured inter-process temperature value near the end is high. This allows the additive manufacturing unit 121 to avoid a situation where point shaping is performed when the inter-process temperature is high after linear shaping, thereby improving the accuracy of additive manufacturing of the additively manufactured object 18.

[0061] Sixth Embodiment In the fifth embodiment, the inter-process temperature, i.e., the inter-pass temperature, is measured. Generally, a radiation thermometer is used as the temperature measurement unit 50 to measure the inter-pass temperature in metal additive manufacturing. However, depending on the modeling material 5 of the additive manufacturing object 18 and the shape of the additive manufacturing object 18, it has been difficult to set the emissivity appropriately. In the sixth embodiment, a case where this emissivity is automatically set will be described.

[0062] In the sixth embodiment, the configurations of the additive manufacturing system 200, the model generating device 130, and the numerical control device 120 are similar to the configurations of the additive manufacturing system 200, the model generating device 130, and the numerical control device 120 in the first embodiment.

[0063] FIG. 14 is a diagram showing how the inter-pass temperature of the layered object 18 is measured in the layered manufacturing apparatus 100 according to the sixth embodiment. FIG. 14 shows the configuration of FIG. 9 described in the third embodiment, to which a numerical control device 120 and a temperature measurement unit 50 have been added. In FIG. 14 , a radiation thermometer is assumed as the temperature measurement unit 50, but a thermal camera or the like may also be used. The layered manufacturing unit 121 of the numerical control device 120 acquires height data from the height sensor 51 and acquires inter-pass temperature data from the temperature measurement unit 50. Using the acquired data, the layered manufacturing unit 121 outputs a supply command for the modeling material 5 to the modeling material supply device 19, a heat source command to the processing head 10, an emissivity setting value to the temperature measurement unit 50, and the like.

[0064] As described above, in the sixth embodiment, the additive manufacturing unit 121 detects the temperature based on the intensity of the emitted light, stores emissivity models for each of the building material 5 and the building shape, and measures the temperature while changing the emissivity based on the models for the building material 5, the building shape, and the emissivity. The additive manufacturing unit 121 stores, for example, a data sheet of emissivity corresponding to each building material 5 and building shape of the additive manufacturing object 18. The additive manufacturing unit 121 can automatically set the emissivity required for inter-pass temperature measurement by selecting the emissivity from the data sheet according to the building material 5, the building shape, etc. of the additive manufacturing object 18. Therefore, the additive manufacturing unit 121 can improve the accuracy of the temperature measurement of the additive manufacturing object 18, thereby also improving the accuracy of additive manufacturing of the additive manufacturing object 18. Regarding the aforementioned phrase "while changing the emissivity," the additive manufacturing unit 121 may change the emissivity according to the building shape, etc., even during additive manufacturing of the same layer.

[0065] As described above, according to this embodiment, the additive manufacturing unit 121 of the numerical control device 120 stores emissivity models for each of the building material 5 and the building shape, and measures the temperature while changing the emissivity based on the building material 5, the building shape, and the emissivity models. This allows the additive manufacturing unit 121 to improve the accuracy of additive manufacturing of the additively manufactured object 18.

[0066] The configurations shown in the above embodiments are merely examples, and may be combined with other known technologies, or different embodiments may be combined with each other. It is also possible to omit or modify parts of the configurations as long as they do not deviate from the gist of the invention.

[0067] 1 Control device, 2 Heat source supply device, 3 Heat source path, 4 Spool drive device, 5 Building material, 6 Wire spool, 7 Gas supply unit, 8 Gas piping path, 10 Processing head, 11 Beam nozzle, 12 Wire nozzle, 13 Gas nozzle, 14 Processing head drive unit, 15 Stage, 16 Stage rotation mechanism, 17 Base plate, 18 Layered model, 19 Building material supply device, 24 Heat source, 25 Shielding gas, 26 Building point, 50 Temperature measurement unit, 51 Height sensor, 90, 93 Processing circuit, 91 Processor, 92 Memory, 100 Layered modeling device, 110 Processing program generation device, 120 Numerical control device, 121 Layered modeling unit, 130 Model generation device, 131 Prototype modeling measurement unit, 132 Model generation unit, 200 Layered modeling system.

Claims

1. where i is an integer of 1 or more, and n, j, and k are integers of 2 or more, a prototype manufacturing measurement step in which a prototype manufacturing measurement unit supplies a manufacturing material, supplies a heating beam for heating to the processing area to melt the manufacturing material, and performs additive manufacturing of beads, which are the manufacturing material in a molten state deposited in the processing area, from the first stage to the nth stage counting from the bottom, under each of processing conditions i=1 to i=k so that the jth bead, which is the bead manufactured by additive manufacturing under the i-th processing condition, is sequentially additively manufactured on top of the j-1th bead, which is the bead manufactured by additive manufacturing under the i-th processing condition, and measures the jth bead width, which is the width of the jth bead, and the jth object height, which is the height of the manufactured object after additive manufacturing of the jth bead, and stores the measurement data in association with the i-th processing condition; a model generation step in which a model generation unit generates, based on the measurement data, a model for additive manufacturing that indicates a relationship between at least the i-th processing condition, the j-th bead width, and the j-th object height.

2. where i is an integer of 1 or greater and n is an integer of 2 or greater, a prototype manufacturing measurement step in which the prototype manufacturing measurement unit supplies a manufacturing material, supplies a heating beam to the processing area to melt the manufacturing material, and additively manufactures beads of the molten manufacturing material deposited in the processing area, from the 1st to nth stages counting from the lowest layer, so that the i-th bead, which is a bead manufactured under the i-th processing conditions, is additively manufactured on the i-1st bead, which is a bead manufactured under the i-1st processing conditions, or on a base plate, and measures the i-th bead width, which is the width of the i-th bead, and the i-th object height, which is the height of the object manufactured after additive manufacturing of the i-th bead, and stores the measurement data in association with the i-th processing conditions; a model generation step in which a model generation unit generates, based on the measurement data, a model for additive manufacturing that indicates at least the relationship between the i-th processing condition, the i-th bead width, and the i-th object height.

3. The model generating method according to claim 1 or 2, characterized in that, in the prototype forming and measuring step, the prototype forming and measuring unit automatically changes the processing conditions for the prototype forming.

4. An additive manufacturing method comprising: an additive manufacturing step in which an additive manufacturing unit performs additive manufacturing under processing conditions determined based on a model generated by the model generation method described in claim 1.

5. An additive manufacturing method comprising: an additive manufacturing step in which an additive manufacturing unit performs additive manufacturing under processing conditions determined based on a model generated by the model generation method described in claim 2.

6. The additive manufacturing method according to claim 4 or 5, wherein m is an integer of 2 or greater, and the additive manufacturing step includes: a bead height measurement step in which the additive manufacturing unit performs additive manufacturing across multiple layers, from p=1 to m, in which the pth bead overlaps the p-1th bead or a base plate, and measures the pth bead height, which is the height of the pth bead from p=1 to m; and a material supply control step in which the additive manufacturing unit uses the measurement result of the p-1th bead height to control processing conditions, including the amount of manufacturing material supplied, during additive manufacturing of the pth bead height based on the measurement result of the p-1th bead height.

7. The additive manufacturing method according to claim 6, characterized in that in the material supply control step, the additive manufacturing unit further uses the measurement results of the first bead height to the p-2nd bead height to control the processing conditions including the amount of molding material supplied during additive manufacturing of the pth bead height based on the measurement results of the first bead height to the p-1th bead height together with the measurement results of the p-1st bead height.

8. The additive manufacturing method according to claim 4 or 5, characterized in that: the model generated in the model generation step of the model generation method is defined as a first model; in the model generation step of the model generation method, a model generation unit of a model generation device executes prototype manufacturing of a specified lower portion of an actual object to generate a second model of the actual object; and in the additive manufacturing step, the additive manufacturing unit uses the second model in the additive manufacturing of the lower portion of the actual object, and additively manufactures a higher portion that is part of the actual object and is to be additively manufactured on top of the lower portion after the formation of the lower portion, using processing conditions determined based on the first model.

9. The additive manufacturing step comprises: a first additive manufacturing step in which the additive manufacturing unit additively manufactures a linear bead in the processing area by supplying a material to supply a modeling material and by supplying a heat source to the processing area to melt the modeling material; and a second additive manufacturing step in which the additive manufacturing unit additively manufactures point-like beads at the start and end portions until the height of the start and end portions becomes flat by measuring the height of the start and end portions of the bead, supplying a small amount of the modeling material in small amounts, and by supplying the heat source to the processing area for a short period of time to melt the small amount of modeling material in point-like manner. an inter-process temperature measurement step in which the additive manufacturing unit measures an inter-process temperature, which is the temperature of the entire object, each time the first additive manufacturing step completes a specified number of layers, and if the inter-process temperature is equal to or lower than a specified temperature threshold, performs the second additive manufacturing step without a pause for cooling, and if the inter-process temperature is higher than the temperature threshold, performs the second additive manufacturing step after providing the pause time.

10. The additive manufacturing method described in claim 9, characterized in that in the inter-process temperature measurement step, the additive manufacturing unit detects the temperature based on the intensity of the emitted light, maintains a model of emissivity for each of the modeling material and the modeling shape, and measures the temperature while changing the emissivity based on the model of the modeling material, the modeling shape, and the emissivity.

11. A prototype manufacturing method in which i is an integer of 1 or greater, and n, j, and k are integers of 2 or greater; a prototype manufacturing measurement unit that supplies a manufacturing material, supplies a heating beam to a processing area to melt the manufacturing material, and additively manufactures beads of the molten manufacturing material deposited in the processing area, from the first stage to the nth stage counting from the lowest layer, under processing conditions i=1 to i=k such that a jth bead that is additively manufactured under the i-th processing condition is sequentially additively manufactured on top of a j-1st bead that is additively manufactured under the i-th processing condition, measures a jth bead width that is the width of the jth bead and a jth object height that is the height of an object manufactured after additive manufacturing of the jth bead, and stores the measured data in association with the i-th processing condition; and a model generation unit that generates, based on the measured data, a model for additive manufacturing that indicates at least the relationship between the i-th processing condition, the jth bead width, and the jth object height. A model generation device comprising:

12. A model generation device comprising: a prototype manufacturing measurement unit that supplies a manufacturing material, supplies a heating beam to a processing area to melt the manufacturing material, and additively manufactures beads of the molten manufacturing material deposited in the processing area, from the 1st to nth stages counting from the lowest layer, so that the i-th bead, which is manufactured under the i-th processing conditions, is additively manufactured on top of the i-1st bead, which is manufactured under the i-1st processing conditions, or a base plate, and measures the i-th bead width, which is the width of the i-th bead, and the i-th object height, which is the height of the manufactured object after additive manufacturing of the i-th bead, and stores the measurement data in association with the i-th processing condition; and a model generation unit that generates, based on the measurement data, a model for additive manufacturing that indicates at least the relationship between the i-th processing condition, the i-th bead width, and the i-th object height.

13. The model generating device according to claim 11 or 12, characterized in that the prototype manufacturing measurement unit automatically changes the processing conditions for the prototype manufacturing.

14. An additive manufacturing device comprising an additive manufacturing unit that performs additive manufacturing under processing conditions determined based on a model generated by the model generation device according to claim 11.

15. An additive manufacturing device comprising an additive manufacturing unit that performs additive manufacturing under processing conditions determined based on a model generated by the model generation device according to claim 12.

16. The additive manufacturing device according to claim 14 or 15, wherein m is an integer equal to or greater than 2, and the additive manufacturing unit performs additive manufacturing across multiple layers in which the pth bead from p=1 to m overlaps the p-1th bead or a base plate, measures the pth bead height, which is the height of the pth bead from p=1 to m, and uses the measurement result of the p-1th bead height to control processing conditions including the amount of modeling material supplied during additive manufacturing of the pth bead height based on the measurement result of the p-1th bead height.

17. The additive manufacturing device according to claim 16, wherein the additive manufacturing unit further uses the measurement results of the first bead height to the p-2nd bead height to control processing conditions including the amount of modeling material supplied during additive manufacturing of the pth bead height based on the measurement results of the first bead height to the p-1th bead height together with the measurement results of the p-1st bead height.

18. The additive manufacturing device according to claim 14 or 15, characterized in that: a model generated by a model generation unit of the model generation device is a first model; the model generation unit of the model generation device executes prototype manufacturing of a specified lower portion of an actual object to generate a second model of the actual object; and the additive manufacturing unit uses the second model in additive manufacturing of the lower portion of the actual object, and additive manufacturing a higher portion that is part of the actual object and is to be additively manufactured on top of the lower portion after the formation of the lower portion, using processing conditions determined based on the first model.

19. The additive manufacturing device according to claim 14 or 15, characterized in that the additive manufacturing unit: performs a first additive manufacturing process to additively manufacture a linear bead in the processing area by material supplying to supply the modeling material and heating and melting by supplying a heat source for heating to the processing area to melt the modeling material; performs a second additive manufacturing process to additively manufacture point-like beads at the start and end portions until the height of the start and end portions becomes flat by start and end terminal measurement to measure the height of the bead, micro material supplying to supply a small amount of the modeling material, and supplying the heat source to the processing area for a short period of time to melt the small amount of modeling material supplied in a point-like manner; measures an inter-process temperature, which is the temperature of the entire object, each time a specified number of layers of the first additive manufacturing process are completed; and performs the second additive manufacturing process without a pause for cooling if the inter-process temperature is equal to or lower than a specified temperature threshold; and performs the second additive manufacturing process after providing the pause time if the inter-process temperature is higher than the temperature threshold.

20. The additive manufacturing device described in claim 19, characterized in that the additive manufacturing unit detects the temperature based on the intensity of the radiated light, maintains a model of emissivity for each of the modeling material and the modeling shape, and measures the temperature while changing the emissivity based on the model of the modeling material, the modeling shape, and the emissivity.

21. An additive manufacturing system comprising: an additive manufacturing device according to any one of claims 14 to 20; and a processing program generation device that provides the additive manufacturing device with a processing program to be used in additive manufacturing of a model.

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