JP6509142B2 - Metal 3D printer and forming method using metal 3D printer - Google Patents

Description

  The present application uses a metal 3D printer and a metal 3D printer that perform shaping by melting a metal wire-like filler (hereinafter referred to as a welding wire) by arc discharge and laminating it on a shaping table. It relates to the modeling method.

  Conventionally, a three-dimensional printer (hereinafter referred to as a 3D printer) for forming a three-dimensional structure by laminating three-dimensional data generated by a computer as a design drawing and laminating cross-sectional shapes of the structure has become widespread. In a 3D printer using a resin, a stereolithography method in which a liquid resin is applied on a molding table, and a layer cured by irradiation with ultraviolet light is stacked over several layers to form a three-dimensional object Also, a hot melt lamination method is used in which resins melted by heat are stacked little by little. In addition, some 3D printers using a resin employ a powder fixing method in which a three-dimensional object is formed by rolling powder resin layer by layer and spraying an adhesive thereon to solidify it.

  Furthermore, among 3D printers, there are metal 3D printers for forming metal three-dimensional objects. In a metal 3D printer, a metal powder is spread on a molding table with a thickness of several tens of microns and then irradiated with laser light to sinter to form one layer, and this is repeated to form a metal shape The modeling of However, since metal powder is considerably expensive compared to resin etc., a metal three-dimensional structure formed by a metal 3D printer is expensive, and this type of 3D printer itself is also expensive. This point has been a hindrance to the spread of metal 3D printers.

  On the other hand, in recent years, as a metal 3D printer for forming a metal three-dimensional shaped object which does not require so much accuracy, there is a metal fusion laminating type metal 3D printer using arc welding. For example, while the metal 3D printer of such a metal fusion | stacking lamination | stacking system is proposed by patent document 1, 2, the product is also utilized practically (refer nonpatent literature 1). The metal fusion lamination type metal 3D printer forms an electric discharge at the tip of the welding wire to melt the welding wire and laminates it on a forming table to form a three-dimensional metal object by molding. .

  Here, a metal fusion lamination type metal 3D printer using arc welding as a target of the present application will be described. FIG. 1 shows the overall configuration of a metal fusion laminating type metal 3D printer 50 utilizing arc welding. On the upper surface 52 of the main body 51 of the metal 3D printer 50, a control unit 1 and a modeling water tank 6 for modeling are provided. Here, the lateral direction of the main body 51 is taken as the X-axis direction, the depth direction as the Y-axis direction, and the height direction as the Z-axis direction. Around the modeling water tank 6, an X-axis actuator 2 for moving the welding torch 5 in the X-axis direction, a Y-axis actuator 4 for moving the welding torch 5 in the Y-axis direction, and a Z-axis actuator 3 for moving in the Z-axis direction are provided. The welding torch 5 for forming is attached to the Y-axis actuator 4.

  Next to the main body 51 of the metal 3D printer 50, a wire supply device 7 for supplying a welding wire to the welding torch 5, a shield gas cylinder 8 for supplying a shielding gas to the welding torch 5, and a welding machine power supply for supplying power to the welding torch 5 9 is provided. Further, inside the main body 51, a cooling medium storage tank 10 for supplying a cooling medium into the modeling water tank 6 at the time of modeling is provided.

  FIG. 2A illustrates the structure of the shaping processing unit 45 of the metal 3D printer 50 shown in FIG. The tip of the welding torch 5 is in the shaping water tank 6. A modeling table 12 is provided as a modeling table in the modeling water tank 6 at a position facing the tip of the welding torch 5. The forming table 12 can be rotated in the vertical direction inside the forming water tank 6 by the θ axis 13.

  The θ axis 13 is rotatably supported on both sides of the modeling water tank 6, as shown in FIG. 2 (b). The θ-axis 13 is rotationally driven by a θ-axis drive motor 13 M provided outside the modeling water tank 6. When the θ axis 13 is rotated, the modeling table 12 can be rotated around the θ axis 13, and the inclination of the modeling table 12 can be changed. The top surface of the forming table 12 can be made vertical by the θ axis 13.

  FIG. 3A shows a system configuration of the metal 3D printer 50 shown in FIG. Welding wire 27 is supplied to welding torch 5 from wire supply device 7, shielding gas is supplied from shielding gas cylinder 8, and power is supplied from welding machine power supply 9. Welding torch 5 is from the tip of welding wire 27. The welding wire 27 is melted by the arc discharge of A base plate 15 is provided as a base on the modeling table 12 inside the modeling water tank 6. The base plate 15 is detachably fixed on the molding table 12 in a state of being separated from the molding table 12 by the spacer 16 as shown in FIG. 3C. Although FIG. 3C shows an example in which the base plate 15 is detachably fixed on the modeling table 12 by the fixing tool 26 in which the spacer 16 is inserted, the spacer 16 needs to be fixed by the fixing tool. There is no.

  The base plate 15 is a plate material that can be welded to a welding material. The reason for separating the shaping table 12 and the base plate 15 is to pass the cooling medium CW between the shaping table 12 and the base plate 15. The welding torch 5 forms a shaped object by laminating the molten welding wire on the base plate 15. FIG.3 (b) shows the modeling table 12 and the baseplate 15 which are arrange | positioned in the modeling water tank 6 shown to Fig.3 (a).

  When the welding torch 5 laminates the molten welding wire 27 on the base plate 15 to form a shaped object, the shaped object being laminated is cooled by the cooling medium CW. The cooling medium CW is stored in the cooling medium storage tank 10 and is cooled by the cooling unit 32. The coolant CW in the coolant storage tank 10 is pumped by the pump 30, the flow rate is controlled by the flow control valve 31, and the coolant is supplied to the modeling water tank 6. Further, the cooling medium CW whose temperature has become high by cooling the object in the modeling water tank 6 is sucked out by the pump 30 ′, and the flow rate is adjusted by the flow control valve 31 ′ to return to the cooling medium storage tank 10. Before shaping on the base plate 15 by the welding torch 5, as shown in FIG. 3C, the height of the liquid surface WL in the shaping water tank 6 is determined by the pumps 30, 30 'and the flow control valves 31, 31. Thus, it is adjusted to a position higher than the lower surface of the base plate 15 and lower than the upper surface.

  Arc discharge is performed from the welding torch 5 to the base plate 15, and the welding wire 27 supplied from the welding torch 5 is melted and solidified to laminate the molten welding wire 27 on the base plate 15 to form a shaped object . The laminated part is called a weld bead. The cooling medium CW is supplied to the inside of the modeling water tank 6 through the pump 30 every time the molten metal is laminated on the base plate 15, and the laminated metal is cooled.

  FIG. 4 shows how the shaped object 18 is shaped by the welding torch 5 and the welding wire 27 on the base plate 15 shown in FIG. 3 (c). During shaping, the fluid level WL of the cooling medium CW is controlled by the flow control valves 31, 31 'so as to be lower than the welding surface WS of the shaped object 18 by a fixed distance H. FIG. 5 shows a state in which the modeling in the modeling water tank 6 of the metal 3D printer 50 shown in FIG. 3A is completed, and the modeled object 18 on which the modeling has been completed is completed on the base plate 15. When the object 18 is finished on the base plate 15 and the temperature drops, the cooling medium CW is returned to the cooling medium storage tank 10.

  The shaped object 18 whose shaping has been completed is taken out together with the base plate 15 from the shaping water tank 6 of the metal 3D printer 50 as shown in FIGS. 6 (a) and 6 (b) in order to perform secondary processing. The removed base plate 15 is attached to a cutting machine (secondary processing machine) (not shown), and as shown in FIG. 6C, the surface of the object 18 is cut by the cutting tool 19. 6 (d) and 6 (e) show a state in which cutting of the object 18 on the base plate 15 is completed. The shaped object 18 which has been subjected to the cutting process is cut off from the top of the base plate 15 by wire cutting or the like to form a finished object shaped object 18P as shown in FIG. 6 (f).

Japanese Patent Laid-Open No. 2000-15363 JP, 2011-83778, A

"Mutoto Kogyo Co., Ltd. product information MA5000-S1", [online], [search December 16, 2015], Internet <URL: https://www.mutoh.co.jp/products/3d/ark/index .html>

  However, in the metal fusion lamination type metal 3D printer using arc welding, the base plate is attached on the forming table and the formed object is formed on the base plate, but the problem is that the base plate is largely deformed by the thermal distortion of the arc welding. there were. Then, in a state where the base plate is thermally deformed, it is difficult to perform secondary processing for cutting the surface of a shaped object formed on the base plate to ensure accuracy, and it takes time for secondary processing. This problem will be described with reference to FIGS. 7 to 9.

  Fig.7 (a) has shown the state in which the baseplate 15 was attached to the modeling table 12 in modeling tank (illustration omitted). In this state, the base plate 15 is flat as shown in FIGS. 8 (a) and 8 (b). FIG.7 (b) has shown the state in which the three-dimensional object 18 was formed by arc welding on the baseplate 15 shown to Fig.7 (a). In this state, since the base plate 15 is fixed on the shaping table 12 by the fixing tool 26, the distortion is corrected by the fixing tool 26 even if it is distorted by heat due to arc welding.

  FIG. 7C shows the base plate 15 and the shaped object 18 removed from the shaping table 12. The base plate 15 is deformed by the thermal strain received during the formation of the object 18 because the correction by the fixture 26 is lost. When the base plate 15 is deformed by thermal strain, for example, as shown in FIG. 8C and FIG. 8D, the portions of the mounting holes 15H at the four corners of the base plate 15 are warped and bent and deformed into a generally downwardly projecting shape. Do.

  FIG. 7 (d) shows a state in which the center line of the attachment hole 15H on the left side of the base plate 15 shown in FIG. 7 (c) is aligned with the reference line RL. The reference line RL is a line serving as a reference when the base plate 15 on which the object 18 is formed is attached to a cutting machine (not shown). FIG. 7 (e) shows the same base line as the base plate 15 and the shaped object 18 in the deformed state shown in FIG. 7 (d) and the base plate 15 'and the shaped object 18 in the normal state without deformation shown by the broken line. It shows the state compared to RL. The distortion of the base plate 15 appears as a deformation of about 3 to 10 mm. As described above, when the base plate 15 on which the three-dimensional object 18 is formed is distorted and deformed, secondary processing is affected. This will be described with reference to FIG.

  FIG. 9A shows an example of another shaped object 21 shaped on a base plate (not shown), and shows a state before secondary processing. When there is no distortion in the base plate, when a normal base plate is attached to a cutting machine (not shown), the secondary processing position 22 of the shaped object 21 fits inside the outer shape of the shaped object 21 as shown by a broken line. It does not go outside of 21. Therefore, when secondary processing is performed on the three-dimensional object 21, cutting processing of the three-dimensional object 21 after forming is normally performed, and the three-dimensional object after secondary processing is in the state illustrated in FIG.

  On the other hand, if there is distortion in the base plate, attaching the distorted base plate to a cutting machine (not shown) causes the secondary processing position 22 of the object 21 to be shaped as shown by the broken line in FIG. It does not fit inside the outer shape of the object 21, and there is a portion that protrudes outside the object 21. The reason for this is that the base plate can not be fixed so that the three-dimensional object is perpendicular to the cutting machine table, and the distortion is large, and the tightening position of the fixing tool of the base plate is deviated. When secondary processing is performed on the shaped object 21 in this state, cutting of the shaped object 21 after shaped is not normally performed, and the shaped object after secondary processing is as shown in FIG. 9 (e). It has a strange shape. In order to prevent this, when the fixing tool is floated and fixed (bulked with a spring washer), there is a problem that the fixing tool is loosened by vibration during processing, and the home position (reference position) is shifted every time. In addition, if the shape of the base plate is taken into consideration so as to increase the machining allowance, the amount of material used will be increased.

  In one aspect, the present application is a metal 3D printer and a metal 3D that can accurately perform secondary processing of a shaped object formed on a base plate even if arc welding is performed to perform formation on a base plate An object of the present invention is to provide a forming method using a printer.

  According to one mode, it is a metal 3D printer for forming a shaped object by melting and laminating a welding material with a welding torch on the upper surface of a base removably installed on a forming table in a forming water tank Between the molding table and the base, a rigid plate having rigidity against external stress is disposed, and the rigid plate and the molding table are detachably fixed in a separated state by the spacer, Between the plate and the base, the spacer is detachably fixed in a state of being separated by the spacer, and the rigid plate is used for the cooling medium supplied in the forming water tank when forming the shaped object on the base. A metal 3D printer is provided, characterized in that it is partially or entirely in contact.

  According to another embodiment, a shaped material is formed by melting and laminating a welding material with a welding torch on the upper surface of a base removably installed on a forming table in the forming water tank, and a formed object is formed The object is taken out from the inside of the modeling water tank and attached to the secondary processing machine, and it is mounted on a secondary processing machine, and in a forming method using a metal 3D printer for forming a shaped object, rigidity against external stress is obtained on the forming table. A rigid plate is detachably fixed in a state of being separated from the molding table by a spacer, and a base is detachably fixed on the rigid plate in a state of being separated from the rigid plate by a spacer, and is on the base When forming a shaped object, the cooling medium is supplied into the forming water tank so that a part or the whole of the rigid plate is in contact with the cooling medium, and the shaped object after forming is taken out together with the rigid plate from the inside of the forming water tank Attaching a rigid plate to a secondary processing machine, molding method using a metal 3D printer, characterized in that secondary processing to shaping the shaped object is provided.

  According to the metal 3D printer of the disclosure and the modeling method using the metal 3D printer, even if the modeling is performed on the base plate, the secondary processing of the modeled object modeled on the base plate by the rigid plate that corrects the deformation of the base plate Has the effect of being able to

BRIEF DESCRIPTION OF THE DRAWINGS It is a perspective view which shows the whole structure of the metal 3D printer of the metal fusion | melting lamination system which utilized arc welding. (A) is a partial perspective view explaining the structure of the shaped part of the metal 3D printer shown in FIG. 1, (b) shows the position of the θ axis drive motor for driving the θ axis of the shaped part shown in (a) It is a partial perspective view shown. (A) is a system configuration diagram of the metal 3D printer shown in FIG. 1, (b) is a partial perspective view showing a state in which a base plate is installed on a modeling table disposed in the modeling water tank shown in (a) (C) is a partial expanded side view of a modeling table and a base plate which were shown to (a). It is a partial side view which shows a mode that a molded article is modeled by a welding torch and a welding wire on the base plate shown in FIG.3 (c). It is a system block diagram which shows the state which modeling of the modeling thing modeled in the modeling water tank of the metal 3D printer shown to FIG. 3A completed. (A) is a perspective view of a state in which a base plate on which a shaped object is formed is taken out from a forming table in a forming water tank of the metal 3D printer shown in FIG. 5; (b) is a side view of (a); Is a side view showing a state in which the base plate shown in (a) is attached to a cutting machine and cut with a cutting tool, and (d) is a perspective view showing after cutting of the shaped object shown in (a) (E) is a side view of (d), and (f) is a perspective view showing a finished product cut out of the base plate. (A) is a side view showing a state in which a base plate is attached to a forming table in a forming water tank, (b) is a side view showing a state in which a formed object is formed by arc welding on a base plate in a forming water tank (C) is a side view showing the base plate shown in (b) removed from the modeling table, (d) is a center line of the attachment hole on the left side of the base plate shown in (c) to the reference line (E) is a side view showing the base plate and the object in the state shown in (d) in comparison with the base plate and the object in the normal state. (A) is a perspective view of a base plate in a normal state, (b) is a side view of (a), (c) is a perspective view of a base plate in a deformed state due to thermal strain, (d) is (c) Side view. (A) is a perspective view of an example of a shaped object before performing secondary processing, (b) is mounted on a cutting machine table with the shaped object shown in (a) attached to a base plate in a normal state (C) is a plan view after secondary processing of the three-dimensional object shown in (b), and (d) is shown in (a). A plan view showing the secondary processing position with respect to the origin position when the shaped object is attached to the base plate in a deformed state by thermal strain and installed on the cutting machine table, (e) is shown in (d) It is a top view after secondary processing of a modeling thing processed at a secondary processing position. BRIEF DESCRIPTION OF THE DRAWINGS (a) is a system block diagram of the metal 3D printer of one Example of this application, (b) is a partial expanded side view of the modeling table, rigid plate, and base plate which were shown to (a). (A) is an exploded perspective view showing a process of attaching a rigid plate on a modeling table and attaching a base plate thereon, (b) is a rigid plate assembled on the modeling table by the process of (a) (C) is a side view of (b). FIG. (A) is a perspective view of an example of a spacer inserted between the shaping table and the rigid plate and the rigid plate and the base plate shown in FIG. 11, (b) is a spacer shown in (a) the rigid plate and the base plate FIG. 7 is a plan view of a rigid plate and a base plate showing a state of being inserted between them. (A) is a partial perspective view explaining the structure of the shaping processing unit of the metal 3D printer shown in FIG. 10 (a), (b) is a welding torch and a welding wire on the base plate shown in FIG. 10 (b) (C) is provided under the base plate shown in (b), and shows the θ axis for rotating the base plate vertically and Φ for rotating it horizontally It is a side view showing an axis. It is a system block diagram of the metal 3D printer which shows the state in which the three-dimensional object was formed on the baseplate of the metal 3D printer shown to Fig.10 (a). (A) is a side view showing a shaped object taken out of the shaped water tank shown in FIG. 14 together with the base plate and the rigid plate, (b) is a machine for cutting the rigid plate shown in (a) The side view which shows the cutting process installed in a table and which cuts the surface with a cutting tool, (c) is a side view showing the state where the cutting process shown in (b) was completed. (A) Remove the rigid plate from the cutting machine shown in FIG. 15 (c), fix the rigid plate to the modeling table again in the modeling tank, and then the modeling table, the welding surface faces the welding torch (B) is a side view showing a process of performing additional formation on the outer peripheral surface of the shaped article shown in (a) using a welding torch and a welding wire, (c) ) Is a perspective view of a shaped object provided with an additional shaped portion formed on a base plate. (A) to (k) show examples of rigid plates that can be used for the metal 3D printer of the present application, and (a) to (c) show oblique views in the case where the rigid plate is a rectangular flat plate (D) is a perspective view showing an embodiment in which parallel ridges are formed on the back surface side of the rigid plate shown in (a) to (c), (e) is a plan view and a side view. (F) and (g) are perspective views and plan views in the case where the rigid plate is disk-like, and (h) is shown in (f) and (g). (I) is a perspective view of the embodiment in which parallel ridges are formed on the back side of the rigid plate, (i) is a perspective view in which the back side on which the parallel ridges of (h) are formed is up ( j) is a perspective view showing an embodiment in which a rib is formed on the back surface side of the rigid plate shown in (a) to (c), (k) is an example of (j) Bed is a perspective view of try on the back side which are formed.

  Hereinafter, embodiments of the present application will be described in detail based on specific examples using the attached drawings. In the metal 3D printer of the present application, the same components as those of the metal 3D printer 50 of the comparative technology described with reference to FIGS. 1 to 9 are denoted by the same reference numerals, and the description thereof is omitted or simplified.

  FIG. 10A shows a metal 3D printer 60 according to an embodiment of the present application, and similar to the metal 3D printer 50 described in FIG. 3A, the shaping processing unit 65, the arc welding apparatus ARK, and The cooling device CM of the modeling water tank 6 is provided. The arc welding apparatus ARK includes a welding torch 5, a wire supply device 7, a shield gas cylinder 8 and a welding machine power supply 9. The cooling device CM also supplies the pump 30 for supplying the cooling medium CW in the cooling medium storage tank 10 cooled by the cooling unit 32 to the modeling water tank 6, and the pump for discharging the cooling medium CW of the flow control valve 31 and the modeling water tank 6. 30 'and a flow control valve 31'. The shaping processing unit 65 will be described later.

  In the metal 3D printer 50 shown in FIG. 3A, only the base plate 15 is provided on the modeling table 12 inside the modeling water tank 6 in a state of being separated from the modeling table 12 by the spacers 16. Met. On the other hand, in the metal 3D printer 60 of the present application, the rigid plate 17 is disposed on the shaping table 12, and the base plate 15 is disposed on the rigid plate 17. The rigid plate 17 is a conductor plate shaped so as to have a rigidity such that deformation is minimal with respect to stress caused by thermal strain of the arranged base plate 15. It is the same in that the molten welding wire 27 is laminated on the base plate 15 by the arc welding apparatus ARK to form a shaped object.

  FIG. 11A shows a process of placing the spacer 16 on the shaping table 12 and attaching the rigid plate 17 with the fixture 26 and placing the spacer 16 on the rigid plate 17 and attaching the base plate 15 with the fixture 26. It is a thing. By the process shown in FIG. 11 (a), a shaped part 40 as shown in FIGS. 11 (b) and 11 (c) is assembled.

  FIG. 10 (b) shows the relationship between the level of the cooling medium CW and the modeling table 12, the rigid plate 17 and the base plate 15 disposed in the modeling water tank 6 shown in FIG. 10 (a). Before the welding torch 5 starts laminating the molten welding wire on the base plate 15, the height of the liquid surface WL in the modeling water tank 6 is determined by the pumps 30, 30 'and the flow control valves 31, 31'. It is adjusted to a position higher than the lower surface of the base plate 15 and lower than the upper surface. Therefore, the rigid plate 17 is always submerged in the cooling medium CW.

  FIG. 12 (a) shows an example of the spacer 16 inserted between the shaping table 12 and the rigid plate 17 and between the rigid plate 17 and the base plate 15 shown in FIG. The spacer 16 of this example is a rectangular solid, and the insertion hole 16H of the fixing tool 26 is provided at the center. The spacer 16 can be made of metal, for example, a wedding nut can be used. FIG. 12B is a plan view of a state in which the spacer 16 shown in FIG. 12A is inserted between the rigid plate 17 and the base plate 15, and shows the arrangement of the spacer 16.

  FIG. 13 (a) illustrates the structure of the shaping processing unit 65 of the metal 3D printer 60 shown in FIG. 10 (a). The front end of the welding torch 5 is in the water tank 6, and a torch cover 11 is attached to the front end for preventing direct view of the arc light. At the position facing the torch cover 11 in the modeling water tank 6, there is the modeling table 12 provided with the rigid plate 17 and the base plate 15 described in FIG. 11, but here the φ axis 14 for rotating the modeling table 12 is shown. For this reason, only the shaping table 12 is shown. The modeling table 12 can be rotated in the vertical direction inside the modeling water tank 6 by the θ axis 13 and can be rotated in the horizontal direction inside the modeling water tank 6 by the φ axis 14.

  FIG. 13 (b) shows how a shaped object 18 is shaped by the welding torch 5 and the welding wire 27 of the shaping processing section 65 on the base plate 15 shown in FIG. 10 (b). When welding torch 5 melts and laminates welding wire 27 on base plate 15, the level WL of cooling medium CW rises every time one layer of molten welding wire 27 is laminated on base plate 15. And the laminated metal is cooled. The liquid surface WL of the cooling medium CW is controlled by the aforementioned cooling device (see FIG. 10A) so as to be lower than the welding surface WS of the object 18 by a fixed distance H.

  In addition to the movement of the welding torch 5 by the X-, Z-, and Y-axis actuators 2, 3, and 4 described in FIG. The base plate 15 can be moved by the θ axis 13 and the φ axis 14 shown. For example, when forming a cylindrical shaped object 18 on the base plate 15, a circle may be drawn by the X-axis actuator 2 and the Y-axis actuator 4, but a circle may be drawn by rotating the φ axis 14 it can. The illustration of the cooling medium is omitted in FIG.

  FIG. 14 shows a state in which the modeling in the modeling water tank 6 of the metal 3D printer 60 shown in FIG. 10A is completed, and on the base plate 15, the modeled object 18 in which the modeling is completed is completed. Here, for example, it is assumed that a cylindrical shaped object 18 is shaped on the base plate 15. When shaping on the base plate 15 is finished and the temperature of the shaped object 18 drops, the cooling medium CW inside the shaping water tank 6 is discharged and discharged by the pump 30 ′ of the cooling device CM and the flow control valve 31 ′. The coolant CW is returned to the coolant storage tank 10. Further, at the time when shaping on the base plate 15 is completed, the welding torch 5 is retracted from above the shaping table 12 by the X, Z, and Y axis actuators of the arc welding apparatus ARK, which is not shown.

  FIG. 15 (a) shows a state in which the object 18 is taken out together with the base plate 15 and the rigid plate 17 from the inside of the water tank 6 shown in FIG. The shaped object 18 taken out of the modeling water tank 6 is placed on the table 28 of the cutting machine together with the rigid plate 17 as shown in FIG. )I do. The rigid plate 17 can be mounted on the table 28 of the cutting machine correctly and accurately because the deformation due to the thermal strain of the base plate 15 is minimal. FIG.15 (c) shows the state to which the cutting by the cutting tool 19 shown in FIG.15 (b) was complete | finished.

  If the final shaped object is cylindrical as shown in FIG. 15 (c), the shaped object 18 may be cut off from above the base plate 15 after secondary processing. On the other hand, when it is necessary to additionally form a projection on the side surface of the cylindrical shaped object 18 shown in FIG. 15C as a final shaped object, the shaped object 18 together with the rigid plate 17 and the base plate 15 is again It is attached and fixed to the modeling table 12. Here, the additional processing will be described using FIGS. 16 (a) to 16 (c).

  16 (a), the rigid plate 17 is removed from the table 28 of the cutting machine shown in FIG. 15 (c), and the rigid plate 17 is fixed again to the forming table 12 in the forming water tank 6, and then the forming table 12 shows a state in which the welding surface of the object 18 is rotated by the θ axis 13 so as to face the welding torch (not shown). As described above, the rigid plate 17 deforms very little with respect to the stress due to the thermal strain of the base plate 15, so that the rigid plate 17 can be correctly mounted on the shaping table 12 as before. Further, even when thermal distortion occurs in the base plate 15 during the formation of the shaped object 18, the base plate 15 is fixed to the rigid plate 17 by the fixing tool 26, and the distortion is corrected. Although illustration of a modeling water tank is omitted in Drawing 16 (a), at the time of attachment of rigid plate 17 to modeling table 12, a cooling medium in a modeling water tank is pulled out.

  In the case shown in FIG. 16A, in the case of forming the projections 18A by performing additional modeling on the outer peripheral surface of the three-dimensional object 18, a cooling medium is supplied into the modeling water tank. FIG. 16B shows a state in which the projection 18A is formed on the outer peripheral surface by performing additional formation on the outer peripheral surface of the object 18 using the welding torch 5 and the welding wire 27. In this case, the cooling medium is supplied to a position indicated by the liquid surface WL lower than the welding surface WS in the modeling water tank (not shown). In a state where the welding table of the object 18 is rotated by the θ axis 13 so that the welding surface of the object 18 faces the welding torch 5, the projection 18A which forms the outer peripheral surface of the object 18 rotates the φ axis 14 By rotating the three-dimensional object 18, it is possible to form a plurality of places on the outer peripheral surface of the three-dimensional object 18.

  After the formation of the projections 18A on the outer peripheral surface of the object 18 is finished, the cooling medium is drained from the inside of the formation water tank after waiting for the temperature decrease of the projections 18A, and then the object 18 is used as the base plate 15 and the rigid plate 17 Take it out together with Then, as described above, the rigid plate 17 is placed on the table of the cutting machine, and the cutting process (secondary process) is performed to cut the surface with the cutting tool. FIG. 16 (c) shows a finished product 18P which is a final product with projections 18A on the outer peripheral surface of the object 18 after the cutting process by the cutting tool is finished. It is a thing. The finished product 18P may be cut out from above the base plate 15.

As described above, according to the disclosed metal 3D printer, the following effects can be obtained.
(1) The rigid plate is minimally deformed with respect to the stress due to the thermal strain of the base plate, so the setup operation is easy to attach to the forming table or cutting machine table while the formed base plate is attached to the rigid plate become.
(2) Since the distortion of the rigid plate is small, it can be attached as it is to the forming table or cutting machine table, facilitating the measurement of the origin of the formed object and miniaturizing the positional deviation in each processing of the formed object. In addition, it is possible to improve the accuracy of the verticality when holding the shaped object vertically and to suppress the loosening of the fixture attached to the spacer.

(3) By using a rigid plate with a small distortion as a reference, it is possible to make a reference position for forming operations a plurality of times, and it is possible to perform additional forming with high accuracy on a shaped object which has been removed and subjected to secondary processing.
(4) Since the accuracy of the origin is improved, it is possible to reduce the machining allowance and the amount of material used for the shaped object, and to suppress the material cost. Specifically, the machining allowance can be reduced to about 1/2 compared to the case where no rigid plate is used.
(5) Since the amount of material used is reduced, the shaping time is shortened and the cutting allowance is reduced, and the cutting time is shortened, so the time to obtain a finished product can be shortened. Specifically, in the case of producing a cylindrically-shaped object having an outer peripheral radius of 15 mm, a plate thickness of 2 mm, and a height of 50 mm, materials necessary for modeling and modeling time can be reduced to about 1/3.

  An example of a rigid plate that can be used in the disclosed metal 3D printer will now be described. FIGS. 17 (a) to 17 (c) show the rigid plate 17 of the first embodiment used in the above-mentioned embodiment, and the rigid plate 17 is a rectangular flat plate. FIGS. 17 (d) and 17 (e) show the rigid plate 17A of the second embodiment, wherein a plurality of ridges 23 are formed and reinforced on the back surface side of the rigid plate 17 of the first embodiment. It is a thing. FIGS. 17 (f) and 17 (g) show the rigid plate 24 of the third embodiment, and the rigid plate 24 has a disk shape. FIGS. 17 (h) and 17 (i) show the rigid plate 24A of the fourth embodiment, and a plurality of ridges 23 parallel to the back surface side of the rigid plate 24 of the fourth embodiment are formed to reinforce them. It is done. FIGS. 17 (j) and 17 (k) show the rigid plate 17B of the fifth embodiment, and a rib 25 is formed on the back side of the rigid plate 17 shown in FIGS. 1 (a) to 1 (c). And it was reinforced. Various modifications of the rigid plate are possible.

  Further, in addition to the flat plate shapes shown in FIGS. 17A to 17C, the base plate 15 also has the shapes shown in FIGS. 17D to 17K to suppress deformation due to thermal strain. Can. And, water can be used as the cooling medium.

Reference Signs List 1 control unit 2 X axis actuator 3 Z axis actuator 4 Y axis actuator 5 welding torch 6 shaped water tank 10 cooling medium storage tank 12 shaped table 13 θ axis 14 φ axis 15 base plate 16 spacer 17, 17A, 17B, 24, 24A rigid plate 18, 21 Shaped object 19 Cutting tool 27 Welding wire 40 Forming portion 50, 60 Metal 3D printer ARK Arc welding device CM Cooling device CW Cooling medium WL Liquid surface WS Weld surface

Claims (6)

A metal 3D printer for forming a shaped object by melting and laminating a melting material with a welding torch on the upper surface of a base removably installed on a forming table in a forming water tank,
A rigid plate having rigidity against external stress is disposed between the molding table and the base,
A spacer is detachably fixed between the rigid plate and the molding table in a state of being separated by a spacer,
The rigid plate and the base are detachably fixed in a state of being separated by a spacer,
The metal 3D printer, wherein the rigid plate is partially or entirely in contact with a cooling medium supplied into the water tank when the object is formed on the base.   The metal 3D printer according to claim 1, wherein the welding torch uses arc welding which melts a welding wire supplied as a solvent.   The 2D object according to claim 1 or 2, characterized in that the shaped object formed on the base can be secondarily processed by removing the rigid plate from the first shaper and attaching it to a second processing machine. Metal 3D printer described. The welding torch is movable in three dimensions by three axes from a first axis to a third axis, and the forming table is capable of horizontal rotation and vertical rotation by orthogonal fourth and fifth axes,
The said 4th axis | shaft and the said 5th axis are rotated, the modeling surface of the modeling thing modeled on the upper surface of the said base can be made to oppose the said welding torch, and modeling is possible. The metal 3D printer according to claim 1 or 2. A shaped material is shaped by melting and laminating a melting material with a welding torch on the upper surface of a base removably installed on a shaping table in a shaping water tank, and the shaped object after shaping is the shaped water tank In the forming method using a metal 3D printer that takes out the whole base from inside, attaches it to a secondary processing machine, and forms a shaped object by secondary processing,
On the forming table, a rigid plate having rigidity against external stress is detachably fixed in a state of being separated from the forming table by a spacer,
The base is detachably fixed on the rigid plate in a state of being separated from the rigid plate by a spacer,
When forming a shaped object on the base, a cooling medium is supplied into the formation water tank so that a part or the whole of the rigid plate is in contact with the cooling medium,
The shaped object after shaping is taken out together with the rigid plate from within the shaping water tank,
Attach the rigid plate to the secondary processing machine to perform secondary processing;
A forming method using a metal 3D printer, wherein a shaped object after secondary processing is cut out from the base to form a shaped object. The modeling method is a modeling method using a metal 3D printer capable of horizontal rotation and vertical rotation by two axes, and in the case of performing additional modeling on the outer surface of the modeled object after secondary processing,
The shaped object after the secondary processing is removed together with the rigid plate from the secondary processing machine before being cut off from the base,
The removed rigid plate is again attached to the molding table,
By rotating the forming table with the two axes while moving the welding torch in a three-dimensional direction, additional modeling is performed on the outer peripheral surface of the secondary-processed formed article,
The shaped object after additive shaping is taken out together with the rigid plate from within the shaping water tank,
The method according to claim 5, wherein the rigid plate is attached to the secondary processing machine and secondary processing is performed to form a three-dimensional object.

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