JP7355672B2 - Manufacturing method for additively manufactured objects - Google Patents

Description

The present invention relates to a method for manufacturing a laminate-molded article.

In recent years, the need for 3D printers as a means of production has been increasing, and research and development is being carried out in the aircraft industry and the like for practical application, particularly for the application of 3D printers to metal materials. A 3D printer using a metal material melts metal powder or metal wire using a heat source such as a laser or an arc, and forms a model by layering the molten metal.

Patent Document 1 describes that a shaped object is formed by filling the inside of a contour created by layered manufacturing with a metal material in a wave-shaped filling pattern having a certain wavelength.

In addition, as a technique for welding a groove, Patent Document 2 describes that when performing multi-layer welding by repeatedly welding the inside of the groove from the bottom to the top one by one using a welding torch, the edges of the weld bead and the It is described that adjustment is made so that the straight line formed by the weld bead end of the weld pass directly below the weld bead has an inclination angle with respect to the weld line.

JP 2019-111582 Publication Japanese Patent Application Publication No. 2002-178153

By the way, according to the modeling method described in Patent Document 1, it is possible to efficiently model a modeled object by filling the inside of the outline. There is a possibility that non-welding may occur between the filled part made of the filled metal material, resulting in quality deterioration.

In addition, it is possible to fill the gap between the wall part and the filling part using the welding method described in Patent Document 1, but the trajectory of the torch must be finely adjusted according to the shape and size of the gap, making the trajectory plan complicated. turn into.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a laminate-molded article that can suppress the occurrence of unwelded parts and efficiently manufacture a high-quality article.

The present invention consists of the following configuration.
A method for manufacturing a laminate-molded article, in which a laminate-molded article is formed by laminating welded beads made by melting and solidifying a filler material, the method comprising:
a frame forming step of forming a frame using the welding bead;
an internal modeling step of forming a plurality of welding beads in the frame along a first direction to create an internal modeling part in which the welding beads are arranged in parallel;
embedding modeling step of forming a weld bead along a second direction intersecting the first direction in the gap formed between at least one end of the internal modeling part and the frame part to fill the gap; and,
including,
A method for manufacturing a layered product.

According to the present invention, it is possible to suppress the occurrence of unwelded parts and efficiently manufacture a high-quality shaped article.

BRIEF DESCRIPTION OF THE DRAWINGS It is a typical schematic block diagram of the manufacturing system which manufactures a layered product by the manufacturing method of embodiment of this invention. It is a top view of a laminate-molded article in the middle of manufacture showing the manufacturing process of a laminate-molded article. It is a top view of a laminate-molded article in the middle of manufacture showing the manufacturing process of a laminate-molded article. It is a top view of a laminate-molded article in the middle of manufacture showing the manufacturing process of a laminate-molded article. It is a top view of a laminate-molded article in the middle of manufacture showing the manufacturing process of a laminate-molded article. It is a top view of a laminate-molded article in the middle of manufacture showing the manufacturing process of a laminate-molded article. FIG. 2A is a sectional view taken along line AA in FIG. 2A. FIG. 2B is a sectional view taken along line BB in FIG. 2B. FIG. 2C is a sectional view taken along line CC in FIG. 2C. FIG. 2D is a sectional view taken along line DD in FIG. 2D. FIG. 2E is a sectional view taken along line EE in FIG. 2E. It is a schematic longitudinal cross-sectional view of the manufactured laminate-molded article. FIG. 7 is a plan view of a part of a layered product in the process of being manufactured, illustrating another example of the embedding manufacturing process.

Embodiments of the present invention will be described in detail below with reference to the drawings.
FIG. 1 is a configuration diagram of a manufacturing system used for manufacturing the layered product of the present invention.
A manufacturing system 100 for a layered product having this configuration includes a layered manufacturing device 11, a controller 13 that centrally controls the layered manufacturing device 11, and a power supply device 15.

The additive manufacturing apparatus 11 includes a welding robot 19 having a torch 17 provided on its tip shaft, and a filler material supply section 21 that supplies filler material (welding wire) M to the torch 17.

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

The torch 17 has a shield nozzle (not shown), and shield gas is supplied from the shield nozzle. The arc welding method may be a consumable electrode method such as coated arc welding or carbon dioxide arc welding, or a non-consumable electrode method such as TIG welding or plasma arc welding, and the method may be selected as appropriate depending on the layered product to be manufactured. Ru.

For example, in the case of a consumable electrode type, a contact tip is arranged inside the shield nozzle, and the filler material M to which melting current is supplied is held in the contact tip. The torch 17 holds the filler metal M and generates an arc from the tip of the filler metal M in a shielding gas atmosphere. The filler material M is fed from the filler material supply section 21 to the torch 17 by a feeding mechanism (not shown) attached to a robot arm or the like. When the continuously fed filler metal M is melted and solidified while moving the torch 17, a linear weld bead B, which is a molten solidified body of the filler metal M, is formed on the base plate 51. A layered product W consisting of welded beads B is modeled.

The controller 13 includes a CAD/CAM section 31, a trajectory calculation section 33, a storage section 35, and a control section 37 to which these sections are connected.

The CAD/CAM section 31 inputs or creates shape data (CAD data, etc.) of the laminate-molded object W to be manufactured, and cooperates with the trajectory calculation section 33 to create a welding bead B representing the manufacturing procedure of the laminate-molded object. Generate a layered model of That is, the shape data is divided into a plurality of layers, and layer shape data representing the shape of each layer is generated. Then, the movement trajectory of the torch 17 is determined based on the layer shape data of the generated layered model. The CAD/CAM unit 31 generates a drive program for the welding robot 19 and power supply device 15 that moves the torch 17 to form a weld bead based on the generated layer shape data and data such as the movement trajectory of the torch 17. . Various data such as the generated driving program are stored in the storage unit 35.

The control unit 37 executes the drive program stored in the storage unit 35 to drive the welding robot 19, power supply device 15, and the like. That is, in response to a command from the controller 13, the welding robot 19 moves the torch 17 along the trajectory of the torch 17 generated by the trajectory calculation unit 33, melts the filler metal M with an arc, and A weld bead B is formed on top.

The base plate 51 is made of a metal plate such as a steel plate, and is basically larger than the bottom surface (lowest layer surface) of the layered product W. Note that the base plate 51 is not limited to a plate shape, and may be a base of other shapes such as a block shape or a rod shape.

As the filler metal M, any commercially available welding wire can be used. For example, it is specified in MAG welding and MIG welding solid wire for mild steel, high tensile strength steel and low temperature steel (JIS Z 3312), arc welding flux cored wire for mild steel, high tensile strength steel and low temperature steel (JIS Z 3313), etc. wire can be used.

In the manufacturing system 100 for a layered product having the above configuration, when the shape data (CAD data, etc.) of the layered product W to be manufactured is input to the control unit 37, the control unit 37 controls the layered product based on the input shape data. A laminated model of the weld bead B representing the procedure for forming the object W is generated.

This lamination model is analytically determined from the input shape data based on various conditions such as shape, material, heat input, etc., based on an appropriate algorithm so as to enable efficient lamination. As a result, a trajectory plan, which is a plan for the stacking procedure and shape of the welding bead B, is determined, and based on this trajectory plan, the trajectory (trajectory of movement) of the torch 17 is determined. Then, the CAD/CAM section 31 generates a drive program based on the determined trajectory of the torch 17 and the trajectory plan of the welding bead B.

The control unit 37 melts the filler metal M protruding from the tip of the torch 17 using an arc to form a linear weld bead B on the base plate 51 according to the drive program. Then, by stacking these welded beads B, a laminate-molded article W is modeled.

Next, a method for manufacturing a layered product using the manufacturing system 100 described above will be described.
FIGS. 2A to 2E are plan views of the laminate-molded article in the middle of manufacture, showing the manufacturing process of the laminate-molded article. 3A to 3E are cross-sectional views of FIGS. 2A to 2E, respectively. FIG. 4 is a schematic vertical cross-sectional view of the manufactured laminate-molded article.

(Frame modeling process)
As shown in FIGS. 2A and 3A, the filler metal M is melted while the torch 17 of the additive manufacturing apparatus 11 is moved by the drive of the welding robot 19. Then, the welding bead B1 made of the melted filler material M is supplied onto the base plate 51, and a frame portion 53 made of the welding bead B1 and having a substantially rectangular shape in plan view is formed on the baseplate 51.

(Internal modeling process)
As shown in FIGS. 2B and 3B, a weld bead B2 is formed inside the frame portion 53. This welding bead B2 is formed within the frame portion 53 along the first direction X from one side to the other side (arrow α direction). In this example, the first direction X is the longitudinal direction of the frame portion 53. Then, the welding beads B2 are formed in order from one side in the width direction within the frame portion 53. As a result, as shown in FIGS. 2C and 3C, an internal shaped portion 55 consisting of a plurality of weld beads B2 formed in parallel is formed within the frame portion 53.

At this time, the welding bead B2 is formed with a starting end and a terminal end separated from the frame portion 53, leaving a gap. Further, the end surfaces 57 at the starting and ending ends of the welding bead B2 are formed into inclined surfaces that gradually slope downward toward the ends. In this way, by forming the end surfaces 57 at the starting and ending ends of the welding bead B2 into inclined surfaces, a groove that gradually widens upward is formed in the gap G between the end 55a of the internal shaped part 55 and the frame part 53. A portion 59 is formed. For example, at the end surface 57 of the welding bead B2, a sloped surface without depressions can be formed by appropriately holding the arc before cutting the arc and stopping the welding.

(Embedded modeling process)
As shown in FIGS. 2D and 3D, the torch 17 is moved along the gap G formed between the end 55a of the internal shaped part 55 and the frame part 53 to form a weld bead B3. This welding bead B3 moves from one side to the other side (direction of arrow β) along a second direction Y that intersects with the first direction Form towards. In this example, the second direction Y is the width direction of the frame portion 53.

Then, as shown in FIGS. 2E and 3E, this gap G is filled by forming a welding bead B3 in the gap G between the end 55a of the internal shaped part 55 and the frame part 53. At this time, the gap G forming the weld bead B3 is a groove 59 that gradually widens upward, so the weld bead B3 is formed in the same manner as in general welding performed during joining. Can be easily formed and filled.

When filling the gaps G with the welding bead B3, each gap G is filled with the welding bead B3 in one pass. Further, this weld bead B3 is formed using a higher welding current than the welding current used when forming the weld bead B2 when forming the internal shaped portion 55.

By performing the above steps, as shown in FIG. 4, an internal shaped part 55 in which welding beads B2 are stacked is formed on the base plate 51 inside a frame part 53 in which welding beads B1 are stacked, and further , a laminated object W is formed in which the gap G between the end 55a of the internal forming part 55 and the frame part 53 is filled with the welding bead B3.

As described above, according to the method for manufacturing a layered product according to the present embodiment, the frame portion 53 is molded and the internal molded portion 55 is molded within the frame portion 53. For example, the internal molded portion 55 can be efficiently shaped by the welding bead B2 having a large cross-sectional area. Moreover, along the second direction Y that intersects the first direction By forming the welding bead B3 to fill the gap G, it is possible to weld the end of the welding bead B2 in the internal shaped part 55 to the frame part 53 while melting it. Thereby, it is possible to manufacture a high-quality laminate-molded product W by suppressing the occurrence of unwelded parts while increasing manufacturing efficiency.

In addition, by forming the end surface 57 of the welding bead B2 into an inclined surface that gradually slopes downward toward the end, the welding bead B2 gradually slopes upward into the gap G between the end 55a of the internal modeling section 55 and the frame section 53. A groove portion 59 that becomes wider is formed. Therefore, in the embedding modeling process, the gap G between the end 55a of the internal modeling part 55 and the frame part 53 can be easily filled by forming the welding bead B3 in the groove part 59, as in the case of normal welding. I can do it. Note that the end surface 57 of the welding bead B2 that forms the internal forming portion 55 can be easily formed by stopping welding at an appropriate timing.

Furthermore, by filling the gap G between the end 55a of the internal modeling part 55 and the frame part 53 at once with the welding bead B3 formed in one pass, productivity can be increased and the trajectory planning can be simplified. Can be done.

Furthermore, by forming a welding bead B3 with a high current in the gap G between the end 55a of the internal shaping part 55 and the frame part 53, this welding bead B3 is well melted into the internal shaping part 55 and the frame part 53. This makes it possible to further suppress the occurrence of unwelded parts.

Next, another example of the embedding modeling process will be explained.
FIG. 5 is a plan view of a part of the laminate-molded article in the process of being manufactured, illustrating another example of the embedding manufacturing process.
As shown in FIG. 5, when a plurality of welding beads B2 are formed in parallel to form the internal modeling part 55 in the internal modeling process, there is a gap between the welding beads B2 at the end 55a of the internal modeling part 55. By creating the depressions, the entire surface becomes uneven.

In this embedding modeling process, a welding bead B3 is formed in the gap G between the end 55a of the internal modeling part 55 and the frame part 53 from one side to the other side (arrow β direction) along the second direction Y. At this time, the torch 17 is weaved (swinged). At this time, the weaving period T of the torch 17 is set to an integral multiple of the pitch P between the welding beads B2 constituting the internal modeling part 55, and the welding bead B2 at the end 55a of the internal modeling part 55 is set in the second direction Y. A welding bead B3 for embedding is formed along the embedding.

In the example shown in FIG. 5, the weaving period T of the torch 17 is matched to the pitch P between the weld beads B2 that constitute the internal shaped portion 55. Then, by weaving the torch 17 in accordance with the pitch P between the welding beads B2 and alternating the path of the torch 17 to the left and right (see arrow γ in FIG. 5), welding at the end 55a of the internal shaped part 55 is achieved. A welding bead B3 for embedding, which is formed along the second direction Y, is embedded between the beads B2.

In this way, by weaving the torch 17 in the embedding modeling process to form the welding bead B3, even if the gap G between the end 55a of the internal modeling part 55 and the frame part 53 is wide, this gap G can be welded. It can be filled well with bead B3.

Further, the weaving period T of the torch 17 is set to be an integral multiple of the pitch P between the weld beads B2 constituting the internal molded part 55, and the welded beads formed along the first direction X at the end 55a of the internal molded part 55 are An embedding welding bead B3 formed along the second direction Y is embedded between B2. In this way, the unevenness at the end portion 55a of the internally shaped portion 55 caused by forming the plurality of welding beads B2 along the first direction This can be well filled by the welding bead B3 for embedding formed along the line. Further, the height of the upper surface of the end portion 55a of the internal shaped portion 55 can also be made equal.

In addition, when shaping the internal shaping part 55, the starting end of the welding bead B2 may be joined to the frame part 53 without a gap. In this case, in the embedding modeling step, the gap G between the terminal end 55a of the welding bead B2 in the internal modeling part 55 and the frame 53 is filled with the welding bead B3.

Furthermore, in the above embodiment, all the welding beads B2 formed along the first direction The direction in which it is formed is not limited as long as it is formed along. For example, the orientation of the plurality of weld beads B2 formed along the first direction X may be alternately changed.

As described above, the present invention is not limited to the embodiments described above, and those skilled in the art can combine the configurations of the embodiments with each other, modify and apply them based on the description of the specification and well-known techniques. It is also contemplated by the present invention to do so, and is within the scope for which protection is sought.

As mentioned above, the following matters are disclosed in this specification.
(1) A method for manufacturing a laminate-molded article, in which a laminate is formed by laminating welded beads made by melting and solidifying a filler material, the method comprising:
a frame forming step of forming a frame using the welding bead;
an internal modeling step of forming a plurality of welding beads in the frame along a first direction to create an internal modeling part in which the welding beads are arranged in parallel;
embedding modeling step of forming a weld bead along a second direction intersecting the first direction in the gap formed between at least one end of the internal modeling part and the frame part to fill the gap; and,
A method for manufacturing a layered product, including:

According to the method for manufacturing a laminate-produced article having the configuration (1) above, the frame part is modeled and the internal model part is modeled within the frame part. It can be shaped. Moreover, a welding bead is formed along a second direction intersecting the first direction in a gap between at least one end of the internal molding section consisting of a plurality of welding beads formed along the first direction and the frame. By filling the gap with the internal molding, it is possible to weld the welding bead to the frame while melting the end of the welding bead in the internal molding. Thereby, it is possible to suppress the occurrence of unwelded parts while increasing manufacturing efficiency, and to manufacture a high-quality laminate-molded article.

(2) In the internal shaping step, at least one end face of the starting end and the terminal end of the welding bead is formed into an inclined surface that gradually slopes downward toward the end, and the end face of the internal shaping part and the frame The method for manufacturing a laminate-molded article according to (1), wherein a groove portion that gradually widens upward is formed in the gap between the groove and the groove.

According to the method for manufacturing a laminate-produced article having the configuration (2) above, by forming at least one end surface of the starting end and the terminal end of the welding bead into an inclined surface that gradually slopes downward toward the end, internal modeling is possible. A groove portion is formed in the gap between the end of the portion and the frame portion to gradually widen upward. Therefore, in the embedding modeling process, the gap between the end of the internal modeling part and the frame part can be easily filled by forming a weld bead in the groove part, as in the case of normal welding. Note that the sloped surface of the weld bead that forms the internal modeling part can be easily formed by stopping welding at an appropriate timing.

(3) The method for manufacturing a laminate-molded article according to (1) or (2), wherein in the embedding modeling step, a torch forming the welding bead is weaved.

According to the method for manufacturing a laminate-molded article having the configuration (3) above, a weld bead is formed by weaving a torch in the embedding modeling process. As a result, even if the gap between the end of the internal shaped part and the frame is wide, this gap can be satisfactorily filled with the welding bead.

(4) The weaving period of the torch is set to be an integral multiple of the pitch between the weld beads that constitute the internal shaped part, and the welded beads formed along the first direction at the end of the internal shaped part The method for manufacturing a laminate-molded article according to (3), wherein the welding bead for embedding formed along the second direction is embedded in the embedding.

According to the method for manufacturing a laminate-produced article having the configuration (4) above, unevenness at the end of the internally formed part caused by forming a plurality of welding beads along the first direction to form the internally formed part is eliminated. , can be well filled by a welding bead for filling formed along the second direction. Furthermore, the height of the upper surface at the end of the internal shaped portion can also be made equal.

(5) Any one of (1) to (4), wherein in the embedding modeling process, the gap between the end of the internal modeling part and the frame part is filled with the welding bead formed in one pass. 1. A method for manufacturing a layered product according to item 1.

According to the method for manufacturing a laminate-molded article having the configuration (5) above, productivity is increased by filling the gap between the end of the internal molding part and the frame part at once with a welding bead formed in one pass. Moreover, trajectory planning can be simplified.

(6) Laminated manufacturing according to any one of (1) to (5), wherein the welding bead formed in the embedded modeling step is formed with a higher current than when forming the welding bead in the internal modeling step. How things are manufactured.

According to the method for manufacturing a laminate-molded article having the configuration of (6) above, by forming a weld bead with a high current in the gap between the end of the internal molding part and the frame, the weld bead is attached to the internal molding part and the frame part. It can be well melted into the frame, and the occurrence of unwelded parts can be further suppressed.

53 Frame section 55 Internal molding section 55a End section 57 End surface 59 Bevel section B, B1, B2, B3 Welding bead G Gap M Filler metal P Pitch T Period W Laminated object X First direction Y Second direction

Claims (6)

A method for manufacturing a laminate-molded article, in which a laminate-molded article is formed by laminating welded beads made by melting and solidifying a filler material, the method comprising:
a frame forming step of forming a frame using the welding bead;
an internal modeling step of forming a plurality of welding beads in the frame along a first direction to create an internal modeling part in which the welding beads are arranged in parallel;
embedding modeling step of forming a weld bead along a second direction intersecting the first direction in the gap formed between at least one end of the internal modeling part and the frame part to fill the gap; and,
including,
A method for manufacturing a layered product. In the internal shaping step, at least one end face of the welding bead, including a starting end and a terminal end, is formed into an inclined surface that gradually slopes downward toward the end, and the end face of the internal shaping part and the frame part are forming a groove in the gap that gradually widens upward;
The method for manufacturing a laminate-molded article according to claim 1. In the embedded modeling step, weaving the torch that forms the welding bead;
The method for manufacturing a laminate-molded article according to claim 1 or 2. The weaving period of the torch is set to be an integral multiple of the pitch between the weld beads constituting the internal molded part, and the weld beads formed along the first direction at the end of the internal molded part have the embedding the welding bead for embedding formed along a second direction;
The method for manufacturing a laminate-molded article according to claim 3. In the embedding modeling step, the gap between the end of the internal modeling part and the frame part is filled with the welding bead formed in one pass.
The method for producing a laminate-molded article according to any one of claims 1 to 4. forming the welding bead formed in the embedded modeling step with a higher current than when forming the welding bead in the internal modeling step;
The method for producing a laminate-molded article according to any one of claims 1 to 5.

Images