JP2021016885A - Lamination planning method for laminate molded object, manufacturing method and manufacturing apparatus for laminate molded object - Google Patents

Abstract

To provide a lamination planning method for a laminate molded object, a manufacturing method and a manufacturing apparatus for a laminate molded object capable of forming a target shape with high accuracy while suppressing influence of release of residual stress generated when the object is separated from the base plate.SOLUTION: A lamination planning method for a laminate molded object comprises, to be performed in the following arranged order: a lamination plan creation step for obtaining a shape model MA of a laminate molded object W to be laminate molded on a base plate 23 on the basis of three-dimensional shape data, and creating a lamination plan for forming the laminate molded object W of the shape model MA; a shape error setting step for setting an allowable shape error α for the laminate molded object W formed on the basis of the shape model MA; a deformation amount calculation step for obtaining a deformation amount δP caused by a release strain generated when the laminate molded object W formed based on the shape model MA is separated from the base plate 23; and a correction step for correcting the shape model MA and the lamination plan until the deformation amount δP falls within a range of the shape error α.SELECTED DRAWING: Figure 5

Description

The present invention relates to a method for planning a laminate of a laminated model, a method for producing a laminated model, and a manufacturing apparatus.

In recent years, there has been an increasing need for modeling using a 3D printer as a means of production, and research and development are being promoted toward the practical application of modeling using metal materials. A 3D printer for modeling a metal material uses a heat source such as a laser, an electron beam, or an arc to melt a metal powder or a metal wire and laminate the molten metal to produce a laminated model.

As a metal 3D printer that shapes a modeled object by arc welding on the base plate, a rigid plate with the modeling table and the base separated by spacers is provided detachably from the modeling table and the base, and on the base. It is known that a rigid plate is submerged in a cooling medium when a modeled object is modeled, and the rigid plate is subjected to secondary processing after modeling (see Patent Document 1).

In addition, it accepts the material property values, modeling conditions, and conditions related to the size of the modeled object for the modeled object formed by laminated modeling, and is based on these conditions and the constraint conditions that quantify the restraint state around the molten pool generated during modeling. A technique for calculating the intrinsic strain from the linear form of the intrinsic strain derived from the above is known (see Patent Document 2).

JP-A-2017-144446 JP-A-2018-184623

By the way, in laminated modeling in which a welded bead is laminated on a base material to form a modeled object, the material is melted and solidified to form the model, so that residual stress is generated inside the modeled object due to heat shrinkage or the like. There is. If the base metal is cut and removed in this state, the modeled object may be deformed due to the release of the residual stress, and an error may occur with respect to the target shape.

With the technique of Patent Document 1 for correcting the deformation of the base plate and the technique of Patent Document 2 for calculating the intrinsic strain of the modeled object to be modeled, it is difficult to suppress an error with respect to the target shape of the modeled object after cutting and removing the base material. Is.

Therefore, the present invention provides a laminating planning method, a laminating model manufacturing method, and a manufacturing apparatus for a laminated model capable of forming a target shape with high accuracy by suppressing the influence of release of residual stress when separated from the base plate. The purpose is to provide.

The present invention has the following configuration.
(1) A method of laminating a laminated model in which a laminated model is modeled using the three-dimensional shape data of the laminated model by a modeling portion in which molten metal is laminated on a base plate.
Based on the three-dimensional shape data, a stacking plan creation step of obtaining a shape model of the laminated model to be laminated on the base plate and creating a stacking plan for laminating the laminated model of the shape model. ,
A shape error setting step for setting an acceptable shape error for the laminated model formed based on the shape model, and a shape error setting step.
A deformation amount calculation step for obtaining the amount of deformation due to release strain when the laminated model formed by the shape model is separated from the base plate.
A correction step of correcting the shape model and the stacking plan until the deformation amount falls within the range of the shape error, and
A method of laminating a laminated model in which the above steps are carried out in this order.
(2) A method for manufacturing a laminated model in which the laminated model is laminated based on the laminated plan created by the method for planning the lamination of the laminated model according to the above (1).
(3) An apparatus for manufacturing a laminated model, in which a laminated model is modeled using the three-dimensional shape data of the laminated model by a modeling unit in which molten metal is laminated on a base plate.
Based on the three-dimensional shape data, a stacking plan creation unit that obtains a shape model of the laminated model to be laminated on the base plate and creates a stacking plan for laminating the laminated model of the shape model. ,
A setting unit that sets an acceptable shape error for the laminated model formed based on the shape model, and a setting unit.
A deformation amount calculation unit for obtaining the amount of deformation due to release strain when the laminated model formed by the shape model is separated from the base plate.
A correction unit that corrects the shape model and the stacking plan until the amount of deformation falls within the range of the shape error.
Equipment for manufacturing laminated objects.

According to the present invention, it is possible to form a target shape with high accuracy by suppressing the influence of release of residual stress when separated from the base plate.

It is a schematic block diagram of the manufacturing apparatus of the laminated model which concerns on this invention. It is a schematic cross-sectional view along the vertical direction of a laminated model. It is schematic cross-sectional view along the vertical direction explaining the procedure of the basic laminated modeling of a laminated model. It is schematic cross-sectional view along the vertical direction explaining the procedure of the basic laminated modeling of a laminated model. It is schematic cross-sectional view along the vertical direction explaining the procedure of the basic laminated modeling of a laminated model. It is schematic cross-sectional view along the vertical direction of the laminated model article explaining the deformation of the laminated model object when the base plate is removed. It is a flowchart which shows the procedure of the stacking plan of a laminated model. It is a schematic diagram of a laminated model which explains the procedure of the laminating plan of a laminated model. It is a schematic diagram of a laminated model which explains the procedure of the laminating plan of a laminated model. It is a schematic diagram of a laminated model which explains the procedure of the laminating plan of a laminated model.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
<Manufacturing equipment for laminated objects>
FIG. 1 is a schematic configuration diagram of a manufacturing apparatus for a laminated model according to the present invention.
The laminated model manufacturing apparatus 100 having this configuration includes a modeling unit 11, a controller 13 that controls the modeling unit 11, and a power supply device 15.

The modeling unit 11 includes a welding robot 19 provided with a torch 17 on the tip shaft, and a filler material supply unit 21 that supplies the filler metal (welding wire) M to the torch 17.

The welding robot 19 is an articulated robot, and the filler metal M is continuously supplied to the torch 17 attached to the tip shaft of the robot arm. The position and posture of the torch 17 can be arbitrarily set three-dimensionally within the range of the degree of freedom of the robot arm.

The torch 17 generates an arc from the tip of the filler metal M in a shield gas atmosphere while holding the filler metal M. The torch 17 has a shield nozzle (not shown), and shield gas is supplied from the shield nozzle. The arc welding method may be either a consumable electrode type such as shielded metal arc welding or carbon dioxide arc welding, or a non-consumable electrode type such as TIG welding or plasma arc welding, and is appropriately selected according to the laminated model to be manufactured. Weld.

For example, in the case of the consumable electrode type, the contact tip is arranged inside the shield nozzle, and the filler metal M to which the melting current is supplied is held by the contact tip. The torch 17 generates an arc from the tip of the filler metal M in a shield gas atmosphere while holding the filler metal M. The filler metal M is fed from the filler metal supply unit 21 to the torch 17 by a feeding mechanism (not shown) attached to a robot arm or the like. Then, when the filler metal M that is continuously fed is melted and solidified while moving the torch 17, a linear welded bead B that is a molten solidified body of the filler metal M is formed on the base plate 23.

The filler metal M is fed from the filler metal supply unit 21 to the torch 17 by a feeding mechanism (not shown) attached to the robot arm or the like of the welding robot 19. Then, the torch 17 moves along a desired welding line by driving the robot arm by a command from the controller 13. Further, the filler metal M that is continuously fed is melted and solidified in a shield gas atmosphere by an arc generated at the tip of the torch 17. As a result, the welded bead B, which is a molten solidified body of the filler metal M, is formed. As described above, the modeling unit 11 is a laminated modeling device for laminating the molten metal of the filler metal M, and the laminated model W is modeled by laminating the welded beads B in a multi-layered manner on the base plate 23.

The heat source for melting the filler metal M is not limited to the above-mentioned arc. For example, a heat source by another method such as a heating method using an arc and a laser in combination, a heating method using plasma, a heating method using an electron beam or a laser may be adopted. When an arc is used, the welded bead B can be easily formed regardless of the material and structure while ensuring the shielding property. When heating with an electron beam or a laser, the amount of heating can be controlled more finely, the state of the welded bead B can be maintained more appropriately, and the quality of the laminated model W can be further improved.

The controller 13 includes a stacking plan creation unit 31, a deformation amount calculation unit 33, a surplus thickness setting unit 34, a program generation unit 35, a storage unit 37, an input unit 39, a display unit 40, and each of these units. It has a control unit 41 to be connected. Three-dimensional shape data (CAD data, etc.) representing the shape of the laminated model W to be manufactured and various instruction information are input to the control unit 41 from the input unit 39. The display unit 40 displays various images based on the image information transmitted from the control unit 41.

The laminated model manufacturing apparatus 100 having this configuration generates a shape model for bead formation using the input three-dimensional shape data, and creates a stacking plan such as a movement locus of the torch 17 and welding conditions. The control unit 41 creates an operation program according to the stacking plan, and drives each unit according to this operation program to laminate and model the laminated model W having a desired shape.

The stacking plan creation unit 31 decomposes the shape model of the input three-dimensional shape data into a plurality of layers according to the height of the welding bead B. Then, for each layer of the disassembled shape model, the trajectory of the torch 17 for forming the welded bead B and the heating conditions (bead width, bead stacking height, etc.) for forming the welded bead B are set. Create a stacking plan that defines (including).

The deformation amount calculation unit 33 analytically obtains the deformation amount generated by the release of the residual stress of the laminated model W when the base plate 23 is removed from the laminated model W formed according to the lamination plan.

The surplus wall amount setting unit 34 sets the surplus wall amount to be a cutting allowance from the machined structure W1 to the outer edge of the laminated model W.

The program generation unit 35 drives each part of the modeling unit 11 to set a modeling procedure for the laminated model W, and creates an operation program for causing the computer to execute this procedure. The created operation program is stored in the storage unit 37.

In addition to storing the operation program in the storage unit 37, the specifications of various drive units of the modeling unit 11 and the material information of the filler metal M are also stored, and when the program generation unit 35 creates the operation program, The stored information is appropriately referred to when executing the operation program. The storage unit 37 is composed of a storage medium such as a memory or a hard disk, and can input and output various types of information.

The controller 13 including the control unit 41 is a computer device including a CPU, a memory, an I / O interface, and the like. The controller 13 has a function of reading data and programs stored in the storage unit 37, executing data processing and an operation program, and a function of driving and controlling each part of the modeling unit 11. The control unit 41 creates and executes an operation program based on an operation from the input unit 39 or an instruction by communication or the like.

When the control unit 41 executes the operation program, each unit such as the welding robot 19 and the power supply device 15 is driven according to a predetermined programmed procedure. The welding robot 19 moves the torch 17 along the programmed trajectory according to the command from the controller 13, and melts the filler metal M by an arc at a predetermined timing to bring the welding bead B to a desired position. Form.

The operation program referred to here is an instruction code for causing the modeling unit 11 to carry out the procedure for forming the welded bead B designed by a predetermined calculation from the input three-dimensional shape data of the laminated model W. The control unit 41 causes the modeling unit 11 to manufacture the laminated model W by executing the operation program stored in the storage unit 37. That is, the control unit 41 reads a desired operation program from the storage unit 37, moves the torch 17 by driving the welding robot 19 according to this operation program, and generates an arc from the tip of the torch 17. As a result, the welded bead B is repeatedly formed on the base plate 23, and the laminated model W is formed.

Each calculation unit such as the stacking plan creation unit 31, the deformation amount calculation unit 33, the surplus thickness setting unit 34, and the program generation unit 35 is provided in the controller 13, but is not limited thereto. Although not shown, the above-mentioned arithmetic unit is provided on an external computer such as a server or a terminal which is separately arranged from the manufacturing apparatus 100 for a laminated model, for example, via a communication means such as a network or a storage medium. It may be provided. By providing the above-mentioned calculation unit in the external computer, it is possible to create a desired operation program without requiring the manufacturing apparatus 100 for the laminated model, and the program creation work is not complicated. Further, by transferring the created operation program to the storage unit 37 of the controller 13, the modeling unit 11 can be operated in the same manner as when the operation program is created by the controller 13.

<Basic procedure for laminated molding>
Next, the procedure of the laminated modeling for the laminated model W of the illustrated example illustrated as a simple model will be briefly described.
FIG. 2 is a schematic cross-sectional view of the laminated model W along the vertical direction. 3A to 3C are schematic cross-sectional views taken along the vertical direction for explaining the basic procedure for laminating the laminated model W. FIG. 4 is a schematic cross-sectional view taken along the vertical direction of the laminated model W for explaining the deformation of the laminated model W when the base plate is removed.

As shown in FIG. 2, the laminated model W according to an example is formed in a cylindrical shape. The laminated model W is modeled on the base plate 23. The base plate 23 is made of a metal plate such as a steel plate, and basically, a base plate 23 larger than the bottom surface (bottom layer surface) of the laminated model W is used. The base plate 23 is not limited to a plate shape, and may be a base having another shape such as a block body or a rod shape. Further, although FIG. 2 shows an example in which one welded bead B forms the bead layer BL for one layer, it is also possible to form the bead layer BL by a plurality of welded beads B.

As shown in FIG. 3A, in order to form the laminated model W, the welding robot 19 moves the torch 17 along the instructed trajectory according to the operation program on the base plate 23 installed in advance. Then, an arc is generated with the movement of the torch 17, and the welding bead B is formed along the trajectory in which the torch 17 moves. The welded bead B is formed by melting and solidifying the filler metal M, and the bead layer BL of the next layer is repeatedly laminated on the formed bead layer BL.

As shown in FIG. 3B, after the laminated model W is formed on the base plate 23, the base plate 23 is cut with a cutting machine such as a wire saw or a diamond cutter to remove the base plate 23 from the laminated model W, and the laminated model W is removed. W is separated. After that, as shown in FIG. 3C, for example, the surplus portion set by the surplus amount setting unit 34 is cut with respect to the laminated model W and processed into a product. The base plate 23 may be removed after cutting the surplus portion of the laminated model W.

By the way, in the layered manufacturing method in which the welded beads B are laminated on the base plate 23 to form the layered model W, since the material is melted and solidified to form the model, residual stress is generated inside the layered model W due to heat shrinkage or the like. It may have occurred. Then, when the base plate 23 is cut and removed from the laminated model W, the laminated model W may be deformed by releasing the residual stress. For example, as shown in FIG. 4, in the laminated model W formed into a cylindrical shape, by removing the base plate 23, the end side joined to the base plate 23 is expanded in diameter by releasing the residual stress, and the target shape is formed. An error may occur with respect to the shape model MA (indicated by the dotted line in FIG. 4). For this reason, it may be difficult to cut the surplus portion portion thereafter to obtain the structure W1.

Here, the welding deformation and residual stress of the laminated model are generally analyzed by a thermal elasto-plastic analysis method using a finite element method (FEM) or a computer simulation using an elastic analysis or the like.

In the thermo-elasto-plastic analysis method, the phenomenon is calculated in consideration of various non-linear elements for each of a large number of minute time steps, so that highly accurate analysis can be performed. On the other hand, in the elastic analysis, since the analysis is performed considering only the linear elements, the analysis can be performed in a short time. When the laminated model W is modeled by the laminated modeling in which the welded beads B are laminated, all the portions of the laminated model W undergo a metal melting / solidification process. When the metal melts and solidifies, natural strain (plastic strain, thermal strain) is generated in the laminated model W. Residual stress due to this natural strain is generated inside the laminated model W. The deformation amount calculation unit 33 analytically obtains a shape change due to such laminated modeling.

The deformation amount calculation unit 33 may be configured to include, for example, a partial model thermal elasto-plastic analysis unit and an overall model elasticity analysis unit. The partial model thermal elasto-plastic analysis unit performs thermal elasto-plastic analysis using a partial model of the modeled object based on the input analysis conditions (laminated modeling conditions, material physical characteristics conditions), and the intrinsic strain (plastic strain, Thermal strain) is calculated. The overall model elasticity analysis unit performs elastic analysis on the entire model of the modeled object based on the calculated intrinsic strain and derives residual stress and the like. The conditions used for the analysis include laminated molding conditions with parameters such as heat source output, heat source type, beam profile, scanning speed, scanning sequence, line offset or preheating temperature, and material Young ratio, proof stress, and linear expansion. There are mechanical property values such as a coefficient and a work hardening index, and material property conditions such as a thermal property value such as thermal conductivity or specific heat.

Such analysis processing is executed by the computer according to the program. That is, the deformation amount calculation unit 33 is a computer including a processor such as a CPU and a storage device such as a ROM (Read Only Memory), a RAM (Random Access Memory), an HDD (Hard Disk Drive), and an SSD (Solid State Drive). Can be configured as. In this case, the functions of each unit can be realized by the processor executing a predetermined program stored in the storage unit 37 including the storage device.

<Laminating plan for laminated objects>
In the present embodiment, the deformation amount calculation unit 33 predicts the deformation amount of the laminated model W after removing the base plate 23, and based on the prediction, a stacking plan for modeling with the target shape model MA with high accuracy is performed. create. Hereinafter, the stacking plan of the laminated model W according to the present embodiment will be described in detail.

FIG. 5 is a flowchart showing a procedure for laminating a laminated model. 6A to 6C are schematic views of the laminated model W for explaining the procedure of the laminating plan of the laminated model W.

First, the controller 13 acquires the three-dimensional shape (3D) data, which is the CAD data of the laminated model to be modeled, from the input unit 39 (S1).

The stacking plan creation unit 31 of the controller 13 determines the shape model MA according to the shape of the acquired three-dimensional shape data, creates a stacking plan to be formed by the welding bead B based on the shape model MA, and creates a welding bead. The conditions for forming B are determined (S2). To determine the conditions, create a trajectory plan that represents the trajectory that moves the torch 17, and determine the welding conditions such as welding current, arc voltage, welding speed, and torch angle when forming the welding bead B using an arc as a heating source. Includes setting.

Specifically, as shown in FIG. 6A, a shape model MA of the laminated model W is generated, and this shape model MA is vertically divided into a plurality of bead layers (10 layers in the illustrated example) BL, and each bead. Corresponding to the layer BL, the orbits for moving the torches 17 are obtained. The trajectory is determined by an operation or the like based on a predetermined algorithm. The orbital information includes, for example, path information such as the spatial coordinates of the path for moving the torch 17, the radius of the path, and the path length, and bead information such as the bead width and bead height of the welded bead B to be formed. Is done. The height of the bead layer BL is determined according to the height of the welded bead B set by the welding conditions.

Next, the allowable shape of the laminated model W that is deformed by removing the base plate 23 after deformation is set, and the shape error α of the allowable shape with respect to the shape model MA is set by the control unit 41 (S3). The allowable shape is, for example, a shape that can be formed into a structure W1 by removing the base plate 23 and processing the deformed laminated model W.

Next, the deformation amount calculation unit 33 obtains the residual stress due to heat shrinkage or the like that occurs in the laminated model W when the created track plan is carried out under the set welding conditions, removes the base plate 23, and removes the residual stress. The amount of deformation δP of the laminated model W when is released is analytically obtained (S4). The amount of deformation δP can be obtained by using any of thermal elasto-plastic analysis, intrinsic strain analysis, and thermoelastic analysis. For example, by performing an analysis by selectively designating one of the above theories by an analysis using the finite element method (FEM analysis), as shown in FIG. 6B, a laminated model when the base plate 23 is removed. The shape of W (shown by the middle dotted line in FIG. 6B) is predicted, and the amount of deformation δP with respect to the shape model MA is obtained. The storage unit 37 stores physical property information and the like according to the material of the filler metal M, and these information are appropriately used for analysis.

The deformation amount δP is compared with the shape error α, and it is determined whether or not the deformation amount δP is equal to or less than the shape error α (S5). When this deformation amount δP is larger than the shape error α, the laminated model W from which the base plate 23 has been removed after modeling has too much deformation, for example, there is no surplus thickness which is a cutting allowance provided for cutting the surroundings thereafter. , Cutting becomes difficult.

In the comparison between the deformation amount δP and the shape error α, when the deformation amount δP is larger than the shape error α (S5: No), the shape model MA is corrected in anticipation of the analytically obtained deformation amount δP. Then, based on the corrected shape model MA, the lamination plan for forming the laminated model W with the welded bead B is corrected, and the conditions for forming the welded bead B are determined (S2). Here, FIG. 6C shows a shape model MA corrected in anticipation of the deformation amount δP. As shown in FIG. 6C, for example, when it is predicted that the end side on the base plate 23 side is deformed so as to expand in diameter by the deformation amount δP due to the release of the residual stress by removing the base plate 23, the original shape model MA ( (Shown by the middle dotted line in FIG. 6C) is corrected in anticipation of the deformation amount δP. That is, the end portion on the base plate 23 side is corrected to the shape model MA (shown by the solid line in FIG. 6C) whose diameter is reduced in the direction opposite to the deformation in which the diameter is expanded by the deformation amount δP. Then, the control unit 41, which is a correction unit, corrects the stacking plan using the corrected shape model MA. In the stacking plan, only the trajectory plan may be corrected, but the heating conditions may be reset as needed. For example, various shape parameters such as bead width and bead height can be adjusted by controlling the increase / decrease of the welding current and changing the amount of heat input. In that case, the adjustment allowance can be expanded, and the optimum stacking plan can be efficiently corrected.

After that, the shape error α of the allowable shape for the corrected shape model MA is set (S3), and the laminated model W formed by the stacking plan based on the corrected shape model MA is deformed when the base plate 23 is removed. The quantity δP is analytically obtained (S4). Then, the deformation amount δP and the shape error α are compared, and it is determined whether or not the deformation amount δP is equal to or less than the shape error α (S5).

The steps S2 to S5 are repeated until the deformation amount δP becomes equal to or less than the shape error α (S5: Yes).

When the deformation amount δP becomes the shape error α or less, the program generation unit 35 creates an operation program showing the procedure for forming the welding bead B based on the stacking plan (track plan, heating conditions) created from the shape model MA. Then, based on this operation program, the welded bead B is laminated on the base plate 23 to form the laminated model W. If the deformation amount δP of the shape model MA created first is less than or equal to the shape error α, the welding bead B is formed based on the lamination plan (track plan, heating conditions) created from the shape model MA. An operation program showing the procedure to be performed is created, and based on this operation program, the welded bead B is laminated on the base plate 23 to form the laminated model W.

As described above, according to the laminating planning method of the laminated model of the present configuration, the shape model MA and the laminating plan are corrected according to the deformation amount δP due to the release strain generated when the laminated model W is separated from the base plate 23. To do. This makes it possible to manufacture the laminated model W with higher shape accuracy in consideration of the amount of deformation δP due to the release strain after separation from the base plate 23.

Moreover, since the deformation amount is obtained by using any of the thermoelastic plasticity analysis, the intrinsic strain method analysis, and the thermoelasticity analysis, the deformation amount can be predicted with high accuracy by the thermoelastic plasticity analysis, the intrinsic strain method analysis, and the thermoelasticity analysis. Is possible.

Further, since the shape model MA is corrected in the direction opposite to the direction in which the deformation due to the release strain occurs, the generated deformation can be easily canceled without requiring complicated calculation.

Then, according to the manufacturing method and manufacturing apparatus of the laminated model having the present configuration, the shape model MA and the stacking plan are corrected according to the deformation amount δP due to the release strain generated when the laminated model W is separated from the base plate 23. .. As a result, it is possible to produce a laminated model W having high shape accuracy in consideration of the amount of deformation δP due to the release strain after separation from the base plate 23.

As described above, the present invention is not limited to the above-described embodiment, and can be modified or applied by those skilled in the art based on the combination of the configurations of the embodiments with each other, the description of the specification, and the well-known technique. This is also the subject of the present invention and is included in the scope for which protection is sought.

For example, in the above example, the laminated model W has a simple cylindrical shape, but the shape of the laminated model W is not limited to this. The more complicated the shape of the laminated model W is, the more remarkable the effects of the above-mentioned lamination plan and manufacturing method are, so that it can be suitably applied.

In addition, this technology is not limited to the case of producing a laminated model by welding, for example, by scanning the processing head facing the powder material, the layers in which the powder material is selectively melted and solidified are laminated. It can also be suitably applied to obtain a laminated model having a three-dimensional shape.

As described above, the following matters are disclosed in this specification.
(1) A method of laminating a laminated model in which a laminated model is modeled using the three-dimensional shape data of the laminated model by a modeling portion in which molten metal is laminated on a base plate.
Based on the three-dimensional shape data, a stacking plan creation step of obtaining a shape model of the laminated model to be laminated on the base plate and creating a stacking plan for laminating the laminated model of the shape model. ,
A shape error setting step for setting an acceptable shape error for the laminated model formed based on the shape model, and a shape error setting step.
A deformation amount calculation step for obtaining the amount of deformation due to release strain when the laminated model formed by the shape model is separated from the base plate.
A correction step of correcting the shape model and the stacking plan until the deformation amount falls within the range of the shape error, and
A method of laminating a laminated model in which the above steps are carried out in this order.
According to this laminating planning method of the laminated model, the shape model and the laminating plan are corrected according to the amount of deformation due to the release strain generated when the laminated model is separated from the base plate. As a result, it is possible to manufacture a laminated model with higher shape accuracy in consideration of the amount of deformation due to the release strain after separation from the base plate.

(2) The method for planning the lamination of a laminated model according to (1), wherein the deformation amount calculation step obtains the deformation amount by using any of thermal elasto-plastic analysis, intrinsic strain analysis, and thermoelastic analysis.
According to this laminating planning method for laminated shaped objects, it is possible to predict the amount of deformation with high accuracy by thermo-elasto-plastic analysis, intrinsic strain analysis, and thermoelastic analysis.

(3) The laminating planning method for a laminated model according to (1) or (2), wherein the correction step corrects the shape model in a direction opposite to the direction in which deformation due to the release strain occurs.
According to this laminating planning method of the laminated model, the deformation that occurs can be easily canceled without requiring complicated calculation.

(4) The laminated model is formed by forming a bead layer with a plurality of welded beads obtained by melting and solidifying a filler metal, and repeatedly laminating a next layer of bead layers on the formed bead layer ( The method for planning the lamination of a laminated model according to any one of 1) to (3).
According to this laminating planning method of the laminated model, a laminating plan for forming a high-strength laminated model formed by the welding bead can be obtained.

(5) The welded bead is formed by melting the filler metal by an arc generated from a torch supported by the tip of a robot arm of a multi-axis robot, and is formed by laminating the laminated model according to (4). Planning method.
According to this laminating planning method of the laminated model, a modeling plan for modeling the laminated model of an arbitrary shape with a high degree of freedom can be obtained.

(6) The laminating planning method for a laminated model according to (5), wherein the laminating plan creating step determines heating conditions including at least one of a welding current, an arc voltage, a welding speed, and a torch angle for forming the welding bead. ..
According to this laminating planning method of the laminated model, the amount of heat input to the laminated model can be accurately grasped, and the amount of deformation generated when separated from the base plate can be accurately predicted. As a result, it is possible to obtain a laminating plan for modeling a laminated model with higher shape accuracy.

(7) A method for manufacturing a laminated model in which the laminated model is laminated based on the laminated plan created by the method for planning the lamination of the laminated model according to (6).
According to this method for manufacturing a laminated model, it is possible to produce a laminated model with higher shape accuracy.

(8) An apparatus for manufacturing a laminated model, in which a laminated model is modeled using the three-dimensional shape data of the laminated model by a modeling unit in which molten metal is laminated on a base plate.
Based on the three-dimensional shape data, a stacking plan creation unit that obtains a shape model of the laminated model to be laminated on the base plate and creates a stacking plan for laminating the laminated model of the shape model. ,
A setting unit that sets an acceptable shape error for the laminated model formed based on the shape model, and a setting unit.
A deformation amount calculation unit for obtaining the amount of deformation due to release strain when the laminated model formed by the shape model is separated from the base plate.
A correction unit that corrects the shape model and the stacking plan until the amount of deformation falls within the range of the shape error.
Equipment for manufacturing laminated objects.
According to this laminated model manufacturing apparatus, the shape model and the laminated plan are corrected according to the amount of deformation due to the release strain generated when the laminated model is separated from the base plate. As a result, it is possible to produce a laminated model with high shape accuracy in which the amount of deformation due to the release strain after separation from the base plate is taken into consideration.

11 Modeling part 17 Torch 19 Welding robot
23 Base plate 31 Lamination plan creation unit 33 Deformation amount calculation unit 41 Control unit (setting unit, correction unit)
100 Manufacturing equipment B Welding bead BL bead layer M Welding material MA Shape model W Laminated model α Shape error δP Deformation amount

Claims (8)

It is a laminating planning method of a laminated model in which a laminated model is modeled using the three-dimensional shape data of the laminated model by a modeling unit in which molten metal is laminated on a base plate.
Based on the three-dimensional shape data, a stacking plan creation step of obtaining a shape model of the laminated model to be laminated on the base plate and creating a stacking plan for laminating the laminated model of the shape model. ,
A shape error setting step for setting an acceptable shape error for the laminated model formed based on the shape model, and a shape error setting step.
A deformation amount calculation step for obtaining the amount of deformation due to release strain when the laminated model formed by the shape model is separated from the base plate.
A correction step of correcting the shape model and the stacking plan until the deformation amount falls within the range of the shape error, and
A method of laminating a laminated model in which the above steps are carried out in this order. The method for planning the lamination of a laminated model according to claim 1, wherein the deformation amount calculation step obtains the deformation amount by using any one of a thermal elasto-plastic analysis, an intrinsic strain method analysis, and a thermoelastic analysis. The laminating planning method for a laminated model according to claim 1 or 2, wherein the correction step corrects the shape model in a direction opposite to the direction in which deformation due to the release strain occurs. The laminated model is formed by forming a bead layer with a plurality of welded beads obtained by melting and solidifying a filler metal, and repeatedly laminating a next layer of bead layers on the formed bead layer. The method for planning the lamination of a laminated model according to any one of 3. The laminating planning method according to claim 4, wherein the welding bead is formed by melting the filler metal by an arc generated from a torch supported at the tip of a robot arm of a multi-axis robot. The laminating planning method according to claim 5, wherein the laminating plan creating step defines heating conditions including at least one of a welding current, an arc voltage, a welding speed, and a torch angle for forming the welding bead. A method for manufacturing a laminated model in which the laminated model is laminated based on the laminated plan created by the method for planning the lamination of the laminated model according to claim 6. It is a manufacturing apparatus for a laminated model that uses a three-dimensional shape data of the laminated model to model a laminated model by a modeling unit that laminates molten metal on a base plate.
Based on the three-dimensional shape data, a stacking plan creation unit that obtains a shape model of the laminated model to be laminated on the base plate and creates a stacking plan for laminating the laminated model of the shape model. ,
A setting unit that sets an acceptable shape error for the laminated model formed based on the shape model, and a setting unit.
A deformation amount calculation unit for obtaining the amount of deformation due to release strain when the laminated model formed by the shape model is separated from the base plate.
A correction unit that corrects the shape model and the stacking plan until the amount of deformation falls within the range of the shape error.
Equipment for manufacturing laminated objects.

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