Modeling Plan Support Device and Program

Abstract

To create an elaborate shaping plan by which a shape based on the shaping plan hardly deviates from an actual shape, in laminating a plurality of weld beads.SOLUTION: A shaping plan support device is provided with a path information obtaining part 31 that divides a target shape of a shaped object into a plurality of bead models and obtains a plurality of paths on which target positions where weld beads are formed along the bead models respectively are preset; a welding condition setting part 33 that sets a welding condition for satisfying a positional relation between the weld beads and surrounding weld beads arranged adjacent to the weld beads specified by the paths, in forming the weld beads on each layer along the paths; a contour predicting part 35 that predicts contours of the weld beads on the basis of the welding condition; and a control information output part 37 that outputs control information in which at least either of the paths or the welding condition is corrected so that a target position where the weld bead other than the weld bead at the lowest layer, of the weld beads constituting the shaped object is formed, is positioned on the contour of the weld bead on a layer lower than the layer on which the weld bead is arranged.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a modeling plan support device and a program.

Background Art

[0002] In recent years, the need for component manufacturing by additive manufacturing using a 3D printer has been increasing, and research and development have been promoted toward the practical application of modeling using metal materials. For example, Patent Document 1 discloses a three-dimensional modeling apparatus that forms a three-dimensional structure by laminating weld beads formed by melting a metal welding wire. In such modeling by laminating weld beads, when forming an overhang shape by stacking upper weld beads obliquely on lower weld beads, the upper weld beads may not reach the target height mainly due to the dripping of molten metal in the gravitational direction. Further, if the lamination process is repeated as it is, not only a large error in the height direction occurs in the entire modeled object, but also the three-dimensional shape itself may collapse. Therefore, in the three-dimensional modeling apparatus of Patent Document 1, when laminating upper weld beads obliquely on lower weld beads, the upper weld beads are formed at positions corrected by an appropriate amount from the center line in the lamination direction (extension direction), and a modeled object having an overhang shape with a target inclination angle is modeled.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the production of a shaped object as described above, the shape of the shaped object represented by three-dimensional CAD data is sliced into a plurality of layers, and a bead formation path (hereinafter referred to as "path") representing the target position of the welding bead designed for each layer, and a shaping plan for determining the welding conditions are created. However, when forming a welding bead based on the created shaping plan, the shape of the shaped object actually laminated may deviate from the planned shape. When forming a welding bead based on such a shaping plan, there is a risk of hindering the continuation of shaping, such as hitting the torch against the shaped object or causing an arc start error due to an excessive gap between the shaped object and the torch. In particular, when manufacturing a shaped object having an overhang shape as described in Patent Document 1, it is difficult to finely adjust the target position of the welding bead. Therefore, it is desired to perform the shaping plan precisely so that the target position of the welding bead set based on the shaping plan and the actual bead shape do not become inconsistent.

[0005] Therefore, an object of the present invention is to provide a shaping plan support device and a program that can create a precise shaping plan in which the deviation between the shaping plan and the actual shape is less likely to occur when laminating a plurality of welding beads.

Means for Solving the Problems

[0006] The present invention has the following configuration. (1) In the shaping of a shaped object formed by repeatedly laminating welding beads formed by melting a filler material held by a manipulator with a heat source device, a shaping plan support device for determining the shaping conditions of the welding beads constituting the shaped object, A path information acquisition unit that divides each layer obtained by dividing the target shape of the shaped object into a plurality of layers into a plurality of bead models having shapes corresponding to the welding beads, and acquires a plurality of paths that define the target positions for forming the welding beads along the respective bead models; A welding condition setting unit that sets welding conditions that satisfy the positional relationship between the welding bead and the surrounding welding beads adjacent to the welding bead defined by the path when forming the welding beads of each layer along the path; A contour prediction unit that predicts the contour of the welding bead based on the welding conditions; A control information output unit that outputs control information obtained by correcting at least one of the pass and the welding conditions so that the target position of the welding bead when forming the welding bead other than the lowermost layer among the welding beads constituting the shaped object is located on the contour of the welding bead of the lower layer of the welding bead; A shaping plan support device comprising: (2) A program for realizing a shaping plan support function for determining the shaping conditions of the welding beads constituting a shaped object in the shaping of a shaped object formed by repeatedly laminating welding beads formed by melting a filler material held by a manipulator with a heat source device, The computer is caused to: A path information acquisition function that divides each layer obtained by dividing the target shape of the shaped object into a plurality of layers into a plurality of bead models having shapes corresponding to the welding beads, and acquires a plurality of paths that define the target positions for forming the welding beads along the respective bead models; A welding condition setting function that sets welding conditions that satisfy the positional relationship between the welding bead and the surrounding welding beads adjacent to the welding bead defined by the path when forming the welding beads of each layer along the path; A contour prediction function that predicts the contour of the welding bead based on the welding conditions; A control information output function that outputs control information obtained by correcting at least one of the path and the welding conditions so that the target position of the welding bead when forming the welding bead other than the lowermost layer among the welding beads constituting the shaped object is located on the contour of the welding bead of the lower layer of the welding bead; A program for realizing the above.

Advantages of the Invention

[0007] According to the present invention, when laminating a plurality of welding beads, it is possible to create a precise shaping plan in which the deviation between the shaping plan and the actual shape is unlikely to occur.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4A

Figure 4B

Figure 4C

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments according to the present invention will be described in detail with reference to the drawings. The additive manufacturing system shown here melts a filler material (welding wire) held by a manipulator using a heat source device to form a welding bead, and repeatedly stacks the formed welding beads into a desired shape to manufacture a shaped object formed by stacking the welding beads. The shaping plan support device supports the creation of a shaping plan by determining the formation path that is the target position of the welding bead and shaping conditions such as welding conditions for manufacturing such a shaped object.

[0010] <Configuration of the additive manufacturing system> An example of the configuration of an additive manufacturing system that operates based on a shaping plan supported by the above-described shaping plan support device will be described. FIG. 1 is a schematic diagram showing the overall configuration of the additive manufacturing system. The additive manufacturing system 100 includes a shaping control device 15, a manipulator 17, a filler material supply device 19, a manipulator control device 21, and a heat source control device 23.

[0011] The manipulator control device 21 controls the manipulator 17 and the heat source control device 23. A controller (not shown) is connected to the manipulator control device 21 so that any operation of the manipulator control device 21 can be instructed from an operator via the controller.

[0012] The manipulator 17 is, for example, an articulated robot, and the filler material M is supported so as to be continuously supplied to a torch 11 provided on the tip axis. The torch 11 holds the filler material M in a state of protruding from the tip. The position and orientation of the torch 11 can be arbitrarily set three-dimensionally within the range of the degrees of freedom of the robot arm constituting the manipulator 17. The manipulator 17 preferably has six or more degrees of freedom, and preferably can arbitrarily change the axial direction of the heat source at the tip. The manipulator 17 may have various forms such as an articulated robot with four or more axes shown in FIG. 1, or a robot equipped with an angle adjustment mechanism on two or more orthogonal axes.

[0013] The torch 11 has a shielding nozzle (not shown), and shielding gas is supplied from the shielding nozzle. The shielding gas blocks the atmosphere, prevents oxidation, nitridation, etc. of the molten metal during welding, and suppresses welding defects. As the arc welding method used in this configuration, it may be either a consumable electrode type such as covered arc welding or carbon dioxide arc welding, or a non-consumable electrode type such as TIG (Tungsten Inert Gas) welding or plasma arc welding, and is appropriately selected according to the shaping object. Here, gas metal arc welding will be described as an example. In the case of the consumable electrode type, a contact tip is arranged inside the shielding nozzle, and the filler metal M to which current is supplied is held by the contact tip. The torch 11 generates an arc from the tip of the filler metal M in a shielding gas atmosphere while holding the filler metal M.

[0014] The filler metal supply device 19 supplies the filler metal M toward the torch 11. The filler metal supply device 19 includes a reel 19a around which the filler metal M is wound and a feeding mechanism 19b that feeds out the filler metal M from the reel 19a. The filler metal M is fed to the torch 11 while being sent in the forward or reverse direction as needed by the feeding mechanism 19b. The feeding mechanism 19b is not limited to the push type arranged on the filler metal supply device 19 side to extrude the filler metal M, and may be a pull type arranged on a robot arm or the like, or a push-pull type.

[0015] The heat source control device 23 is a welding power source that supplies the electric power required for welding by the manipulator 17. The heat source control device 23 adjusts the welding current and welding voltage supplied during bead formation for melting and solidifying the filler metal M. Also, in conjunction with welding conditions such as the welding current and welding voltage set by the heat source control device 23, the filler metal supply speed of the filler metal supply device 19 is adjusted.

[0016] The heat source for melting the filler material M is not limited to the above-described arc. For example, other heating methods such as a heating method that combines an arc and a laser, a heating method that uses plasma, a heating method that uses an electron beam or a laser, etc. may be adopted. When heating with an electron beam or a laser, the heating amount can be controlled more finely, the state of the formed bead can be maintained more appropriately, and it can contribute to further improvement in the quality of the laminated structure. Also, the material of the filler material M is not particularly limited. For example, depending on the characteristics of the shaped object W, the type of filler material M used may be different, such as mild steel, high-tensile steel, aluminum, aluminum alloy, nickel, nickel-based alloy, etc.

[0017] The shaping control device 15 comprehensively controls each of the above-described parts.

[0018] The laminated shaping system 100 having the above-described configuration operates according to a shaping program created based on the shaping plan of the shaped object W. The shaping program is composed of a number of instruction codes and is created based on an appropriate algorithm according to various conditions such as the shape, material, and heat input amount of the shaped object. According to this shaping program, while moving the torch 11, the filler material M that is fed is melted and solidified, and a linear weld bead B that is a molten solid of the filler material M is formed on the base 13. That is, the manipulator control device 21 drives the manipulator 17 and the heat source control device 23 based on a predetermined program provided from the shaping control device 15. The manipulator 17 moves the torch 11 while melting the filler material M with an arc according to a command from the manipulator control device 21 to form the weld bead B. By sequentially forming and laminating the weld beads B in this way, a shaped object W having the desired shape is obtained.

[0019] FIG. 2 is a functional block diagram of the shaping control device 15. The shaping control device 15 includes a path information acquisition unit 31, a welding condition setting unit 33, a contour prediction unit 35, and a control information output unit 37, and functions as a shaping plan support device. Although the details of each part will be described later, the general functions are as follows.

[0020] The path information acquisition unit 31 divides each layer obtained by dividing the target shape of the shaped object into a plurality of layers into a plurality of bead models having shapes corresponding to the welding beads, and acquires information on a plurality of paths that determine the aiming positions for forming the welding beads along the respective bead models.

[0021] When forming the welding beads of each layer along the acquired paths, the welding condition setting unit 33 sets the welding conditions so as to satisfy the positional relationship between the welding beads and the surrounding welding beads adjacent to the welding beads defined by the determined paths. That is, the welding conditions are set so that welding beads of an appropriate size are formed on the determined paths.

[0022] Based on the set welding conditions, the contour prediction unit 35 predicts the contour of the welding beads formed along the paths using a model simulating the bead shape.

[0023] The control information output unit 37 outputs control information obtained by correcting at least one of the paths and the welding conditions according to the predicted contour of the welding beads in the lower layer of the welding beads when forming the welding beads. By modifying the shaping plan with this control information, a more appropriate shaping plan can be created.

[0024] The above-described shaping control device 15 is configured by hardware using an information processing device such as a PC (Personal Computer). Each function of the shaping control device 15 is realized by a control unit (not shown) reading out a program having a specific function stored in a storage device (not shown) and executing the program. Examples of the storage device include memories such as a RAM (Random Access Memory) which is a volatile storage area, a ROM (Read Only Memory) which is a non-volatile storage area, and storage devices such as an HDD (Hard Disk Drive) and an SSD (Solid State Drive). Examples of the control unit include a processor such as a CPU (Central Processing Unit) and an MPU (Micro Processor Unit), or a dedicated circuit. In addition to the above-described form, the shaping control device 15 may be another computer remotely connected from the additive manufacturing system 100 via a network or the like.

[0025] <Support Procedure for Shaping Plan> FIG. 3 is a flowchart showing the procedure for determining a shaping plan by the shaping plan support device. FIGS. 4A, 4B, and 4C are explanatory diagrams showing an example of the procedure for determining the path of the welding bead for shaping the laminate in a cross section orthogonal to the longitudinal direction of the welding bead. First, the shape of the shaped object is obtained from shape data such as CAD data. Then, as shown in FIG. 4A, the target shape So of the shaped object to be produced is divided into a plurality of layers L1, L2, L3, L4 according to the bead height H of a predetermined welding bead. The number of divided layers and the bead height can be arbitrarily set, and the specific method of dividing the shape is not particularly limited, and known means can be adopted.

[0026] Each of the divided layers L1, L2, L3, and L4 is divided into a plurality of rectangular bead models BM0 so as to correspond to the cross-sectional shape of the weld bead as shown in FIG. 4B. As a result, each of the layers L1, L2, L3, and L4 is divided into a plurality of rectangular bead models BM0. When dividing the rectangular bead model BM0, conditions such as making the bead cross-sectional area constant in the orthogonal cross-section in the bead longitudinal direction may be specified for each rectangular bead model BM0.

[0027] The plurality of divided rectangular bead models BM0 are fitted to a semicircular shape, which is a simple geometric figure shown as an example, as shown in FIG. 4C. Here, each rectangular bead model BM0 is changed to a bead model BM having a base 41 and an arc 43 in a semicircular shape. Although the shape of the bead model BM is arbitrary, if the relationship between the welding conditions and the bead shape is managed as a database in advance, it may be set with reference to the database.

[0028] Then, as a representative position of the obtained semicircular shape, for example, the midpoint of the base 41 is set as the target position P of the weld bead. The target position P, which is the midpoint, is a line formed by a group of points along the longitudinal direction of the bead model BM continuous in the depth direction of FIG. 4C, and this line becomes the path PS for forming the weld bead. The path PS is set for each of the plurality of bead models BM. The path PS includes information on the target position for forming the weld bead and information on the planned height (bead height H) of the weld bead. In addition to obtaining the path PS by fitting the bead model BM to the entire shaped shape, the path PS for the entire shaped shape may be obtained by replicating in parallel the path PS obtained by partially generating a part of the shaped shape.

[0029] The path information acquisition unit 31 shown in FIG. 2 acquires the information of the path PS obtained as described above (S1). The path PS may be calculated and obtained by the path information acquisition unit 31, or may be read from that obtained by another computer or the like.

[0030] Next, the welding condition setting unit 33 sets the welding conditions for the welding bead based on the path PS which is the target position (S2). Specifically, the cross-sectional area (or volume) of the welding bead is obtained from the positional relationship of the path PS. FIG. 5 is an explanatory diagram showing the relationship between the target position P of the path PS and the contour of the lower layer welding bead. In FIG. 5, the target position of the lower layer welding bead is P 0 , and the contour 45 of the welding bead is shown by a broken line. Among the stacked welding beads, if the bead cross-sectional area of the lower layer welding bead is too small, the target position P of the upper layer welding bead will be a position floating from the lower layer welding bead (upper left in FIG. 5). Also, if the bead cross-sectional area of the lower layer welding bead is too large, the target position P of the upper layer welding bead will be a position buried in the lower layer welding bead (upper right in FIG. 5). In a shaping plan with such a positional relationship, since it hinders the continuation of shaping, it is desirable to set the welding bead to be stacked on the lower layer welding bead to a bead cross-sectional area that minimizes the distance between at least the bead surface (contour 45) of the lower layer welding bead and the target position P of the upper layer welding bead. That is, it is advisable to set the target position of the welding bead to be stacked so as to be located on the contour 45 of the lower layer welding bead.

[0031] The welding condition setting unit 33 obtains the bead cross-sectional area (volume) of the upper layer welding bead as described above, and sets the welding conditions for realizing this bead cross-sectional area. Examples of welding conditions include welding current, welding voltage, torch movement speed (welding rod feeding speed), filler material feeding speed, etc. To set the welding conditions, as an example, the welding conditions that are closest to the obtained bead cross-sectional area may be searched from a database that associates parameters such as the weld cross-sectional area, bead height, and bead width with the welding conditions. Also, an approximate formula may be created based on the above-described database, and the welding conditions may be calculated by giving information on the bead height and bead width corresponding to the required bead cross-sectional area in the approximate formula and solving it.

[0032] For example, the bead height H may be obtained from Equation (1), and the bead width LW may be obtained from Equation (2). H =C 1 +C 2 W f +C3 T s + C 4 W f 2 + C 5 T s 2 + C 6 W f T s ··· Equation (1) LW = D 1 + D 2 W f + D 3 T s + D 4 W f 2 + D 5 T s 2 + D 6 W f T s ··· Equation (2) T s : Torch movement speed W f : Filler metal feeding speed C 1 ~ C 6 : Coefficient D 1 ~ D 6 : Coefficient

[0033] In addition, since the distance between the target positions P obtained by the bead model BM is too wide or too narrow, it may occur that the welding conditions for including the target position P of the welding bead in the contour 45 of the lower layer welding bead described above cannot be specified. In that case, after deleting or adding the target position P, the welding conditions may be searched again. That is, the target position P of the welding bead is set at a position having a distance different from the distance between the target positions P defined by the plurality of passes PS, and the welding conditions in which the target position P is included in the contour 45 of the lower layer welding bead are searched again. By doing so, the welding conditions that can include the target position P in the contour 45 of the lower layer welding bead can be easily specified.

[0034] Next, based on the target position acquired in step S1 and the welding conditions searched in step S2, the contour prediction unit 35 further accurately predicts the contour of the welding bead (S3). As a prediction method, information on a model simulating the bead shape is prepared in advance, and by giving the target position and welding conditions as parameters to the model information, a specific model shape is set, and the contour of the model shape thus obtained is treated as the contour of the predicted welding bead. As the shape of the model used at this time, in addition to the shape conforming to the semi-circular shape described above, a model considering the overlap between adjacent beads, a model reproducing the shape in which the molten metal drips to the lower layer side, etc., may be a model reproducing the phenomena that occur when the welding beads are actually stacked.

[0035] FIG. 6 is an explanatory diagram showing an example of a model considering the overlap between adjacent beads. FIG. 6 shows three model shapes in a cross section orthogonal to the longitudinal direction of the welding bead. In each model, the cross-sectional shape of the model BM1 of the reference path P1 is trapezoidal, the model BM2 of the path PS2 is provided adjacent to the model BM1, and the model BM3 of the path PS3 is provided adjacent to the model BM2. The models BM2 and BM3 partially overlap the model arranged on the left side of FIG. 6. Specifically, the models BM2 and BM3 are basically the same trapezoidal shape as the model BM1, and with one end of the bottom side of the trapezoid on the side opposite to the model BM1 side as the center, while maintaining the cross-sectional shape as it is, it is rotated clockwise by a predetermined angle to incline the bottom side of the trapezoid. Then, the overlapping portion of the model BM2 and the model BM1 is regarded as the region of the model BM1, and the lower region of the model BM2 not included in the model BM1 is included in the region of the model BM2. Similarly, the overlapping portion of the model BM3 and the model BM2 is regarded as the region of the model BM2, and the lower region of the model BM3 not included in the model BM2 is included in the region of the model BM3.

[0036] As a result, the shape of the model BM2 becomes a polygonal shape (pentagon) close to one hypotenuse of the model BM1, and the shape of the model BM3 becomes a polygonal shape (pentagon) close to one hypotenuse of the model BM2. Thus, each of BM1, BM2, and BM3 has a shape approximated to the cross-sectional shape of the actual welding bead.

[0037] FIG. 7 is an explanatory diagram showing an example of a model that reproduces the shape in which the weld metal droops downward. FIG. 7 also shows the model shape in a cross section orthogonal to the longitudinal direction of the weld bead. A model BM1 with a trapezoidal cross-sectional shape laminated on the base 13, and among the models BM2, BM3, ···, BMn (n is an integer) in the upper layer than the model BM1, for the upper trapezoidal bead models BM2, BM3, ···, BMn, drooping portions 47A and 47B extending downward are added to both ends of the base 41. The drooping portions 47A and 47B are triangles each having one side as an end of the base 41, and their shapes and areas are set according to the welding conditions and passes of the above-described welding bead. The drooping portion 47A and the drooping portion 47B may have the same shape as each other or different shapes from each other. Further, in addition to providing a pair, the drooping portions 47A and 47B may be provided only at one end of the base 41 of the trapezoidal model BM1.

[0038] By setting the models BM2, BM3, ···, BMn provided with the drooping portions 47A and 47B as bead models for the lamination plan, the bead height of the welding bead is less likely to be affected by the drooping of the molten metal generated in the welding bead. As a result, even under conditions where the molten metal of the welding bead such as the overhang portion is likely to droop, the predicted shape and the actual shape of the contour are likely to be matched.

[0039] Using the model as described above, predict the contour of the model when set to a model size according to the welding conditions.

[0040] For example, in the case of the model having a trapezoid and a drip portion shown in FIG. 7, as shown in FIG. 2, the contour prediction unit 35 includes a drip amount prediction unit 51, a bead height correction unit 53, and a contour output unit 55, and predicts the contour by each unit. That is, the drip amount prediction unit 51 predicts the amount of dripping of the molten metal generated by melting the filler material during bead formation to the lower layer according to the welding conditions of the welding bead. The bead height correction unit 53 corrects the bead height of each bead model in the bead stacking portion according to the predicted dripping amount. The contour output unit 55 outputs the contour based on the corrected bead height. The prediction of the dripping amount may be obtained from, for example, a database prepared in advance that represents the relationship between various welding conditions and the dripping amount.

[0041] Next, the control information output unit 37 shown in FIG. 2 determines the target position for forming adjacent welding beads based on the predicted contour from the above-set model (S4). FIG. 8 is an explanatory diagram showing the relationship between the predicted contour and the target position for forming the welding bead. Note that FIG. 8 also shows the approximate stacked target shape 57 of the welding bead. Further, the contour shown here is represented by a substantially semi-circular curve for simplicity of explanation, but the shape of the contour may be other shapes such as the trapezoid and polygon described above.

[0042] As a result of predicting the contour for a plurality of passes when stacking the welding beads, as in the state before correction in FIG. 8, the target positions P2 and P3 up to the pass PS2 and the pass PS3 are located on the contour 45 of the lower layer pass. However, the contour 45 of the pass PS3 does not intersect the target position of the pass PS4. When such a pass PS4 exists, in the pass where the welding bead is stacked thereon, a deviation occurs between the actual position where the welding bead is formed and the bead formation position of the set pass PS. And in the topmost pass, the deviations of each layer may accumulate and a large deviation may occur.

[0043] Therefore, when the contour 45 of the path PS3 does not intersect with the aiming position in the upper layer as in the corrected state of FIG. 8, the aiming position P4 in the upper layer of the path PS4 is changed to the contour 45 of the lower path PS3. That is, the height of the aiming position P4 corresponding to the path PS4 is changed from the height H, which is the interval between the paths, to Ha.

[0044] The corrected aiming position P described above may be set, for example, as the intersection of the bead extension line Ls extending in the stacking direction of the upper welding bead laminated on the lower welding bead and the predicted contour 45 of the lower welding bead as the aiming position of the upper welding bead. In that case, the inclination angle required for forming the overhang portion can be accurately maintained. Also, the welding position of the upper bead can be uniquely determined.

[0045] Also, when the stacking direction is inclined, the aiming position P may be further adjusted to accurately maintain the inclined shape of the shaped object. FIG. 9 is a schematic diagram showing a partial enlargement of the relationship between the aiming position of the welding bead shown in FIG. 8 and the predicted contour. In the case shown in FIG. 9, in the path PSi+1, which is the upper layer of the path PSi of the aiming position Pi, the aiming position Pi+1 obtained from the above-described model is set. This aiming position Pi+1 is corrected to the aiming position Pai+1 at the intersection with the predicted contour 45 of the path PSi. Thus, when the bead extension line Ls is inclined at an inclination angle θ from the vertical direction and the predicted contour 45 is deviated from the vertical direction (θ > 0), the aiming position Pai+1 may be corrected to the aiming position Pbi+1 moved in the opposite direction of the deviation direction (arrow S direction). That is, the aiming position is moved to the left along the contour 45 of the path PSi+1 from the position intersecting the bead extension line Ls. According to this, it is possible to suppress the shaped object with the welded beads stacked from falling in the direction in which the inclination angle θ in the stacking direction increases due to its own weight.

[0046] By repeating the above steps S2 to S4 for each path (total number of paths: N) (S5, S6), the welding conditions and the target position are sequentially determined. Note that when the prediction of the contour and the setting of the welding conditions become redundant, it is not necessary to execute the processing of S2 to S4 for all paths, and the correction amounts of the welding conditions and the target positions of other paths may be applied as they are.

[0047] Next, the control information output unit 37 sets the welding conditions for the Nth layer (final layer) (S7). In the case shown in FIG. 8, for the contour 45 of the welding bead corresponding to the final layer (path PSN), since there is no welding bead in the layer above the welding bead, the condition of intersecting the above-described contour with the target position cannot be used. Therefore, for the final layer, a virtual target position may be provided in the upper layer.

[0048] FIG. 10 is an explanatory diagram showing the relationship between the predicted contour and the target position for forming the welding bead when a virtual target position is provided on the surface of the final layer. The welding bead of the path PS5 that becomes the final layer in FIG. 10 is formed at the target position P5. In this path PS5, originally, there is no target position on the upper layer side, but the target position P6 of the virtual path PS6 is virtually set on the uppermost surface of the stacking target shape 57. Then, the contour 45 is determined so that this target position P6 is included in the contour 45 of the path PS5. Thereby, the welding conditions can be set for the path PS5 in the same manner as for other paths.

[0049] Note that the target position P6 set for the virtual path PS6 may be, for example, the point where the bead extension line Ls reaches the uppermost surface of the stacking target shape 57. Further, the stacking target shape 57 may not necessarily be the outer edge shape of the shaped portion that becomes the product, but may be a shape with an added necessary amount of surplus material. That is, by setting the target position of the virtual path on the surface with surplus material added to the final shape of the shaped object, the welding conditions can be adjusted considering the surplus material.

[0050] Also, when welding conditions that match the height of the above-described final layer cannot be found, a new target position may be added and welding conditions that match may be set. The control information output unit 37 outputs, as a path that becomes the torch 11's torch movement position shown in FIG. 1, the target position set as described above, together with welding conditions, as control information.

[0051] According to the shaping plan support device having the above-described configuration, among the welding beads constituting the shaped object, when forming the welding beads other than the lowermost layer, at least one of the path and the welding conditions is corrected so that the target position is located on the contour of the welding bead of the lower layer of the welding bead, and control information is output. If the shaping plan is corrected according to the control information, the formation conditions of the welding beads are optimized so that the target position of the upper welding bead is always located on the predicted contour of the welding bead. Therefore, it is possible to create a shaping plan in which the target position of the upper welding bead does not get buried inside the lower welding bead or float in the air above the lower welding bead, and a situation where the shaping is interrupted does not occur.

[0052] Also, under the condition of fixing the set path, the welding conditions of the lower welding bead may be set so that the contour of the lower welding bead includes the target position of the upper welding bead. In that case, since the number of parameters to be adjusted is limited, the processing can be speeded up and the time for creating the shaping plan can be shortened.

[0053] On the other hand, under the condition of allowing the target position of the welding bead to move from the target position defined by the path, the welding conditions of the welding bead may be set. In that case, the adjustment range of the welding conditions can be expanded, and the welding conditions can be adjusted more flexibly.

[0054] As described above, the present invention is not limited to the above-described embodiments, and it is also contemplated by the present invention that those skilled in the art can combine each configuration of the embodiments with each other, make changes, and apply them based on the description in the specification and well-known techniques, and these are included in the scope for which protection is sought.

[0055] As described above, the following matters are disclosed in this specification. (1) In the shaping of a shaped article formed by repeatedly laminating weld beads formed by melting a filler material held by a manipulator with a heat source device, a shaping plan support device for determining the shaping conditions of the weld beads constituting the shaped article, A path information acquisition unit that divides each layer obtained by dividing the target shape of the shaped article into a plurality of layers into a plurality of bead models having shapes corresponding to the weld beads, and acquires a plurality of paths that define the aiming positions for forming the weld beads along the respective bead models, A welding condition setting unit that sets welding conditions that satisfy the positional relationship between the weld bead and the surrounding weld beads adjacent to the weld bead defined by the path when forming the weld beads of each layer along the path, A contour prediction unit that predicts the contour of the weld bead based on the welding conditions, A control information output unit that outputs control information obtained by correcting at least one of the path and the welding conditions so that the aiming position of the weld bead when forming the weld beads other than the lowermost layer among the weld beads constituting the shaped article is located on the contour of the weld bead of the lower layer of the weld bead, A shaping plan support device comprising: According to this shaping support device, the path information acquisition unit acquires a path corresponding to the target shape of the shaped article, and the welding condition setting unit sets the welding conditions for forming the weld beads of each path. Based on the welding conditions, the contour prediction unit predicts the contour of the weld bead, and the control information output unit outputs information on the path and the welding conditions such that the upper and lower weld beads are formed at appropriate aiming positions and with appropriate sizes as control information. Thereby, a shaping plan that can always perform stable and accurate shaping can be created.

[0056] (2) The shaping plan support device according to (1), wherein an intersection point between a bead extension line extending in the lamination direction of the upper weld bead laminated on the lower weld bead and the predicted contour of the lower weld bead is set as the aiming position of the upper weld bead. According to this shaping support device, when the shaped object has an overhang portion, the inclination angle required for forming this overhang portion can be accurately maintained. Also, the welding position of the upper layer bead is uniquely determined.

[0057] (3) The control information output unit sets the welding conditions of the lower layer welding bead so that the contour of the lower layer welding bead includes the target position of the welding bead of the upper layer of the welding bead under the condition that the path is fixed, for the shaping plan support device according to (1) or (2). According to this shaping support device, since the number of parameters to be adjusted is limited, correction processing can be performed at high speed, and the processing time for creating a shaping plan can be shortened.

[0058] (4) The welding condition setting unit sets the welding conditions of the welding bead under the condition that the target position of the welding bead allows movement from the target position defined by the path, for the shaping plan support device according to (1) or (2). According to this shaping support device, the adjustment range of the welding conditions can be expanded, and the welding conditions can be adjusted more flexibly.

[0059] (5) When the welding condition setting unit cannot set the welding conditions so that the target position of the welding bead is included in the contour of the lower layer welding bead, the target position of the welding bead is set at a position having a different interval from the interval between the target positions defined by the path, and then the welding conditions of the lower layer welding bead are set again so as to include the target position, for the shaping plan support device according to (4). According to this shaping support device, the target position can be more surely included in the contour of the lower layer welding bead.

[0060] (6) The path information acquisition unit obtains a virtual path for forming a welding bead on the uppermost surface of the shaped object, The welding condition setting unit sets the welding conditions of the lower layer welding bead so that the target position of the virtual path is included in the contour of the lower layer welding bead of the target position, for the shaping plan support device according to any one of (1) to (5). According to this shaping support device, the welding conditions can be set for the topmost welding bead in the same manner as for the lower welding beads.

[0061] (7) The aiming position of the virtual path is set on the surface with extra material added to the final shape of the shaped object, for the shaping plan support device according to (6). According to this shaping support device, welding conditions considering extra material can be set.

[0062] (8) The contour prediction unit Among the plurality of bead models, in a bead stacking portion where the bead models overlap vertically, a dripping amount prediction unit that predicts the amount of molten metal dripping downward during bead formation according to the welding conditions of the welding bead, A bead height correction unit that corrects the bead height of each bead model in the bead stacking portion according to the predicted dripping amount, And a contour output unit that outputs the contour based on the corrected bead height, for the shaping plan support device according to any one of (1) to (7). According to this shaping support device, even under conditions where the molten metal of the welding bead is likely to drip, such as in an overhang portion, the predicted shape and the actual shape of the contour are likely to be matched.

[0063] (9) A program for realizing a shaping plan support function for determining the shaping conditions of the welding beads constituting a shaped object in the shaping of a shaped object formed by repeatedly stacking welding beads formed by melting a filler material held by a manipulator with a heat source device, In a computer, A path information acquisition function that divides each layer obtained by dividing the target shape of the shaped object into a plurality of layers into a plurality of bead models having shapes corresponding to the welding beads, and acquires a plurality of paths that define the aiming positions for forming the welding beads along each bead model, When forming the welding beads of the respective layers along the path, a welding condition setting function for setting welding conditions that satisfy the positional relationship between the welding bead and the surrounding welding beads adjacent to the welding bead defined by the path, a contour prediction function for predicting the contour of the welding bead based on the welding conditions, a control information output function for outputting control information obtained by correcting at least one of the path and the welding conditions so that the target position of the welding bead when forming the welding beads other than the lowermost layer among the welding beads constituting the shaped object is located on the contour of the welding bead of the lower layer of the welding bead, A program for realizing the above. According to this program, a path corresponding to the target shape of the shaped object is acquired, and welding conditions for forming the welding beads of each path are set. Based on the welding conditions, the contour of the welding bead is predicted, and information on the path and welding conditions in which the upper and lower welding beads are formed at an appropriate target position and with an appropriate size is output as control information. Thereby, a shaping plan that can always perform stable and accurate shaping can be created.

Explanation of Signs

[0064] 11 Torch 13 Base 15 Shaping control device 17 Manipulator 19 Welding material supply device 19a Reel 19b Pay-out mechanism 21 Manipulator control device 23 Heat source control device 31 Path information acquisition unit 33 Welding condition setting unit 35 Contour prediction unit 37 Control information output unit 41 Base 43 Arc 45 Contour 47A, 47B Dripping part 51 Dripping amount prediction unit 53 Bead height correction unit 55 Contour output unit 57 Stacking target shape 100 Additive manufacturing system So Target shape B Weld bead BM Bead model L1, L2, L3, L4 Layers M Filler material PS1, PS2, PS3 Passes Ls Bead extension line P, P 0 Aiming position W Object to be manufactured

Claims

1. In the shaping of a shaped article formed by repeatedly laminating weld beads formed by melting a filler material held by a manipulator with a heat source device, a shaping plan support device for determining the shaping conditions of the weld beads constituting the shaped article, a path information acquisition unit that divides each layer obtained by dividing the target shape of the shaped article into a plurality of layers into a plurality of bead models having shapes corresponding to the weld beads, and acquires a plurality of paths that define target positions for forming the weld beads along the respective bead models; a welding condition setting unit that sets welding conditions that satisfy the positional relationship between the weld bead and the surrounding weld beads adjacent to the weld bead defined by the path when forming the weld beads of each layer along the path; a contour prediction unit that predicts the contour of the weld bead based on the welding conditions; a control information output unit that outputs control information obtained by correcting at least one of the path and the welding conditions so that the target position of the weld bead when forming the weld bead other than the lowermost layer among the weld beads constituting the shaped article is located on the contour of the weld bead of the lower layer of the weld bead; A shaping plan support device comprising:

2. The intersection of a bead extension line extending in the lamination direction of the upper weld bead laminated on the lower weld bead and the predicted contour of the lower weld bead is set as the target position of the upper weld bead, The shaping plan support device according to claim 1.

3. The control information output unit sets the welding conditions of the lower weld bead so that the contour of the lower weld bead includes the target position of the upper weld bead of the weld bead under the condition that the path is fixed. The shaping plan support device according to claim 1.

4. The welding condition setting unit sets the welding conditions of the weld bead under the condition that the target position of the weld bead is allowed to move from the target position defined by the path. The shaping plan support device according to claim 1.

5. When the welding condition setting unit cannot set the welding conditions so that the target position of the weld bead is included in the contour of the lower weld bead, the target position of the weld bead is set at a position having a different interval from the interval between the target positions defined by the path, and then the welding conditions of the lower weld bead are set again so as to include the target position. The shaping plan support device according to claim 4.

6. The path information acquisition unit obtains a virtual path for forming a welding bead on the surface at the uppermost part of the shaped object, The welding condition setting unit sets the welding conditions for the lower layer welding bead so that the target position of the virtual path is included in the contour of the lower layer welding bead at the target position, The shaping plan support device according to any one of claims 1 to 5.

7. The target position of the virtual path is set on the surface with surplus material added to the final shape of the shaped object, The shaping plan support device according to claim 6.

8. The contour prediction unit, Among the plurality of bead models, in a bead stacking portion where the bead models overlap vertically, a dripping amount prediction unit that predicts the amount of molten metal dripping down to the lower layer during bead formation according to the welding conditions of the welding bead, A bead height correction unit that corrects the bead height of each bead model in the bead stacking portion according to the predicted dripping amount, And a contour output unit that outputs the contour based on the corrected bead height. The shaping plan support device according to claim 1.

9. In the shaping of a shaped object formed by repeatedly stacking welding beads formed by melting a filler material held by a manipulator with a heat source device, a program for realizing a shaping plan support function for determining the shaping conditions of the welding beads constituting the shaped object, On a computer, A path information acquisition function that divides each layer obtained by dividing the target shape of the shaped object into a plurality of layers into a plurality of bead models having shapes corresponding to the welding beads, and acquires a plurality of paths that define the target positions for forming the welding beads along the respective bead models, A welding condition setting function that sets welding conditions that satisfy the positional relationship between the welding bead and the surrounding welding beads adjacent to the welding bead defined by the path when forming the welding beads of each layer along the path, A contour prediction function that predicts the contour of the welding bead based on the welding conditions, A control information output function that outputs control information obtained by correcting at least one of the path and the welding conditions so that the target position of the welding bead when forming the welding beads other than the lowermost layer among the welding beads constituting the shaped object is located on the contour of the welding bead in the lower layer of the welding bead, A program for realizing the above.

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