Additive processing method, additive processing apparatus, and additive processing program

Abstract

This invention provides a lamination processing technology that can suppress the generation of burrs in subsequent cutting or removal processes after lamination processing. [Solution] The method for adding workpieces comprises the steps of: lowering the floor surface of the workpiece processing area; spreading metal powder material in the processing area after lowering the floor surface of the processing area; irradiating the metal powder material spread in the processing area with laser light; and repeating the steps of lowering, spreading, and irradiating to stack workpieces of a predetermined shape on a plate mounted on the floor surface. The workpiece includes a processing surface which is to be cut or removed after the completion of stacking workpieces of a predetermined shape, and a workpiece portion adjacent to the processing surface. The stacking step includes stacking in such a way that the width of the workpiece portion in the direction parallel to the processing surface increases as it moves away from the processing surface.

Description

Technical Field

[0001] The present disclosure relates to an additive manufacturing method, an additive manufacturing apparatus, and an additive manufacturing program.

Background Art

[0002] Japanese Patent Application Laid-Open No. 2022-33955 (Patent Document 1) discloses a layered manufacturing apparatus that performs layered manufacturing by the SLM (Selective Laser Melting) method. The SLM method is a method of realizing layered manufacturing by irradiating a metal powder material spread over a processing area with laser light and locally melting and solidifying the metal powder material.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] After the layered manufacturing, some cutting or removal processing may be performed. Patent Document 1 does not disclose the cutting and removal processing in the post-process of the layered manufacturing. Burrs may be generated by the cutting or removal processing in the post-process of the layered manufacturing.

[0005] The present disclosure has been made to solve the above-described problems, and an object in one aspect is to provide a layered manufacturing technology capable of suppressing the generation of burrs in the cutting or removal processing in the post-process of the layered manufacturing.

Means for Solving the Problems

[0006] One example of the present disclosure provides a method for adding material to a workpiece. The method for adding material to a workpiece includes the steps of: lowering the floor surface of the workpiece processing area; spreading a metal powder material in the processing area after lowering the floor surface of the processing area; irradiating the metal powder material spread in the processing area with laser light; and repeating the lowering step, the spreading step, and the irradiating step to stack workpieces of a predetermined shape on a plate mounted on the floor surface. The workpiece includes a processing surface which is to be cut or removed after the completion of stacking the workpieces of the predetermined shape, and a workpiece portion which is adjacent to the processing surface. The stacking step includes stacking the workpieces such that the width of the workpiece portion in a direction parallel to the processing surface increases as it moves away from the processing surface.

[0007] In one example of this disclosure, the surface to be machined in the workpiece includes the contact surface with the plate.

[0008] In one example of this disclosure, the cutting process includes wire electrical discharge machining for separating the workpiece from the plate.

[0009] In one example of this disclosure, the workpiece portion has a tapered shape in which the width increases as it moves away from the surface to be machined.

[0010] In one example of this disclosure, the surface to be machined in the workpiece includes the surface machined by a milling cutter.

[0011] Another example of the present disclosure provides an additive processing apparatus. The additive processing apparatus comprises a recoater for spreading metal powder material in a processing area of ​​a workpiece; a lifting mechanism configured to raise and lower the floor surface of the processing area; a plate configured to be detachably attached to the floor surface; an irradiation mechanism capable of performing stacking of the workpiece by irradiating the metal powder material spread in the processing area with laser light; and a control unit capable of stacking a workpiece of a predetermined shape in the processing area by repeatedly supplying the metal powder material to the processing area with the recoater, lowering the floor surface with the lifting mechanism, and irradiating with laser light with the irradiation mechanism. The workpiece includes a processing surface which is to be cut or removed after the completion of stacking of the workpiece of the predetermined shape, and a workpiece portion adjacent to the processing surface. The control unit performs stacking such that the width of the workpiece portion in a direction parallel to the processing surface increases as it moves away from the processing surface.

[0012] In other examples of this disclosure, a program for additive processing of a workpiece is provided. The additive processing program causes a computer to perform the steps of: lowering the floor surface of a workpiece processing area; spreading a metal powder material in the processing area after lowering the floor surface of the processing area; irradiating the metal powder material spread in the processing area with laser light; and repeating the steps of lowering, spreading, and irradiating to stack workpieces of a predetermined shape on a plate mounted on the floor surface, wherein the workpiece includes a processing surface which is to be cut or removed after the completion of stacking the workpieces of the predetermined shape, and a workpiece portion adjacent to the processing surface. The stacking step includes stacking such that the width of the workpiece portion in a direction parallel to the processing surface increases as it moves away from the processing surface.

[0013] The above and other objects, features, aspects and advantages of the present invention will become apparent from the following detailed description relating to the invention, which will be understood in conjunction with the accompanying drawings.

Brief Description of the Drawings

[0014] [Figure 1] It is a diagram showing an example of the device configuration of the additive processing device. [Figure 2] It is a diagram showing the SLM-based layer processing steps in chronological order. [Figure 3] It is a diagram showing the layer processing steps according to the embodiment in chronological order. [Figure 4] It is a diagram showing an example of a workpiece formed on a base plate. [Figure 5] It is a diagram showing the cross-section of the workpiece along the V-V line shown in FIG. 4 from the positive side in the Z-axis direction. [Figure 6] It is a diagram showing an example of the drive mechanism of the additive processing device. [Figure 7] It is a diagram showing an example of the hardware configuration of the control unit. [Figure 8] It is a flowchart showing the flow of the layer processing by the additive processing device.

Modes for Carrying Out the Invention

[0015] Hereinafter, each embodiment according to the present invention will be described with reference to the drawings. In the following description, the same parts and components are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed descriptions thereof will not be repeated. In addition, each of the embodiments and each modification described below may be selectively combined as appropriate.

[0016] <A. Additive Processing Device 100> First, referring to FIG. 1, the additive processing device 100 according to the embodiment will be described. FIG. 1 is a diagram showing an example of the device configuration of the additive processing device 100.

[0017] For the sake of convenience of explanation, hereinafter, the direction parallel to the gravitational direction is also referred to as the "Z-axis direction". The Z-axis direction corresponds to the vertical direction. Also, the downward direction (gravitational direction) is also referred to as the positive side of the Z-axis direction, and the upward direction is also referred to as the negative side of the Z-axis direction.

[0018] Also, the direction on the horizontal plane perpendicular to the Z-axis direction is also referred to as the "X-axis direction". The X-axis direction corresponds to the left-right direction when viewing the additive processing apparatus 100 from the front. Also, the right direction when viewing the additive processing apparatus 100 from the front is also referred to as the positive side of the X-axis direction, and the left direction when viewing the additive processing apparatus 100 from the front is also referred to as the negative side of the X-axis direction.

[0019] Furthermore, the direction on the horizontal plane perpendicular to both the X-axis direction and the Z-axis direction is also referred to as the "Y-axis direction". In FIG. 1, the Y-axis direction indicates the front-back direction of the paper. Also, the back side when viewing the additive processing apparatus 100 from the front side is also referred to as the positive side of the Y-axis direction, and the front side of the additive processing apparatus 100 is also referred to as the negative side of the Y-axis direction.

[0020] The additive processing apparatus 100 is a processing machine capable of performing layer processing of a workpiece by the SLM method. The additive processing apparatus 100 irradiates a laser beam onto the spread metal powder material, and locally melts and solidifies the metal powder material to perform layer processing of the workpiece.

[0021] The additive processing apparatus 100 includes a lifting mechanism 130, a lifting mechanism 140, a recoater 150, and a laser irradiation mechanism 160.

[0022] Also, inside the additive processing apparatus 100, a storage area AR1 for the metal powder material PM is provided. The metal powder material PM is the material of the workpiece W. Any metal powder that can be melted by the laser beam LS can be adopted as the metal powder material PM.

[0023] The storage area AR1 is partitioned and formed by, for example, the lifting mechanism 130 and the wall surface 132. The wall surface 132 is configured to surround the upper surface of the lifting mechanism 130 in a top view.

[0024] The upper surface of the lifting mechanism 130 forms the floor surface of the storage area AR1. The upper surface of the lifting mechanism 130 is also configured to move up and down in the Z-axis direction. The lifting mechanism 130 is moved up and down by, for example, the motor 212Z (see Figure 6), which will be described later. The top of the storage area AR1 is open, and when the lifting mechanism 130 rises, the metal powder material PM is pushed out of the storage area AR1.

[0025] Furthermore, a processing area AR2 for the workpiece W is provided inside the additional processing device 100. The processing area AR2 is partitioned, for example, by a lifting mechanism 140 and a wall surface 142. The wall surface 142 is configured to surround the upper surface of the lifting mechanism 140 when viewed from above.

[0026] The upper surface of the lifting mechanism 140 forms the floor surface of the machining area AR2. The lifting mechanism 140 is configured to move up and down in the Z-axis direction. The lifting mechanism 140 is moved up and down by, for example, the motor 222Z (see Figure 6), which will be described later. The upper part of the machining area AR2 is open.

[0027] A base plate 144 may be mounted on the upper surface of the lifting mechanism 140. The base plate 144 may be fixed to the lifting mechanism 140 by, for example, a chuck mechanism (not shown). The base plate 144 is fixed to the lifting mechanism 140 before the start of the lamination process by the additive processing device 100.

[0028] The recoater 150 is configured to spread the metal powder material PM extruded from the storage area AR1 into the processing area AR2. The recoater 150 is composed of blades or rollers, etc.

[0029] More specifically, the recoater 150 extends in the Y-axis direction. The width of the recoater 150 in the Y-axis direction is longer than the width of the storage area AR1 in the Y-axis direction, and also longer than the width of the processing area AR2 in the Y-axis direction.

[0030] Further, the recoater 150 is configured to be drivable in the X-axis direction. The driving of the recoater 150 is realized, for example, by a motor 232X (see FIG. 6) described later. The recoater 150 is configured to be at least passable through a storage area AR1 and a processing area AR2 in a top view. When the recoater 150 is driven in the negative X-axis direction, the metal powder material PM extruded from the upper surface of the storage area AR1 is conveyed to the processing area AR2. Thereby, the metal powder material PM is supplied from the storage area AR1 to the processing area AR2.

[0031] The laser irradiation mechanism 160 irradiates the laser beam LS onto the metal powder material PM spread in the processing area AR2, and selectively melts and solidifies the metal powder material PM. As an example, the laser irradiation mechanism 160 is composed of a laser oscillator, an optical system, and a laser scanner.

[0032] The laser oscillator is a device that generates high-energy laser light. The optical system condenses the laser light generated by the laser oscillator to generate the laser beam LS. For the laser scanner, for example, a galvanometer scanner is used. The galvanometer scanner is composed of a galvanometer mirror for deflecting the laser beam LS in the X-axis direction and a galvanometer mirror for deflecting the laser beam LS in the Y-axis direction. The additive processing apparatus 100 irradiates the laser beam LS at an arbitrary position on the XY plane by controlling the driving of the two galvanometer mirrors.

[0033] <B. Laminated Processing Step> Next, referring to FIG. 2, the laminated processing step of the SLM method will be described. FIG. 2 is a diagram showing the laminated processing step of the SLM method in time series.

[0034] In step S1, the additive processing apparatus 100 raises the lifting mechanism 130. The lifting width of the lifting mechanism 130 is preset. When the lifting mechanism 130 rises, the metal powder material PM is extruded from the storage area AR1.

[0035] Further, the additive processing apparatus 100 lowers the elevating mechanism 140. The lowering width of the elevating mechanism 140 is preset. The lowering width corresponds to the thickness of one layer of the workpiece W. Thereby, a space where no metal powder material PM exists is formed in the processing area AR2.

[0036] In step S2, the additive processing apparatus 100 drives the recoater 150, which is waiting at a predetermined position, in the negative X-axis direction. At this time, the additive processing apparatus 100 drives the recoater 150 so that, in a top view, the recoater 150 passes through the storage area AR1 and the processing area AR2 in this order. Thereby, the recoater 150 evenly spreads the metal powder material PM extruded from the storage area AR1 over the processing area AR2. Then, the additive processing apparatus 100 returns the recoater 150 to the predetermined standby position.

[0037] In step S3, the additive processing apparatus 100 controls the laser irradiation mechanism 160 according to the additive processing program and irradiates the laser light LS onto the metal powder material PM spread over the processing area AR2. At this time, the laser light LS is irradiated onto the metal powder material PM on the base plate 144. The metal powder material PM at the irradiated portion of the laser light LS melts and solidifies. Thereby, the first layer SL1 of the workpiece W is formed.

[0038] After that, the additive processing apparatus 100 repeats the processes of steps S1 to S3 to form a workpiece W with a predetermined shape on the base plate 144 mounted on the floor surface of the processing area AR2.

[0039] <C. Outline> In a post-process of the laminated processing, some cutting or removing process may be performed on the workpiece W. Examples of the cutting process in the post-process of the laminated processing include wire electrical discharge machining for separating the workpiece W from the base plate 144. Examples of the removing process in the post-process of the laminated processing include cutting (e.g., milling) for shaping the workpiece W.

[0040] If cutting or removal processing is performed on the workpiece W in a subsequent process, burrs may be generated. Therefore, the additive processing apparatus 100 according to this embodiment performs lamination processing in such a way that burrs are less likely to be generated in the cutting or removal processing of the subsequent process.

[0041] The following describes the lamination process according to the embodiment, with reference to Figure 3. Figure 3 is a diagram showing the lamination process according to the embodiment in chronological order.

[0042] Furthermore, in the following, the workpiece surface that is scheduled to undergo cutting or removal processing in a post-lamination process will be referred to as the "processing surface SF". Examples of processing surfaces SF include the contact surface between the base plate 144 and the workpiece W, and the surface processed by a milling cutter.

[0043] Furthermore, in the following, the portion of the workpiece W connected to the machining surface SF will be referred to as the "workpiece portion WP". If the cross-section of the workpiece is defined as a cross-section located at a predetermined distance from the machining surface SF in the direction perpendicular to the machining surface SF, then the workpiece portion WP corresponds to the portion of the workpiece W between the machining surface SF and the said workpiece cross-section.

[0044] In step S11, the additive manufacturing apparatus 100 performs the additive manufacturing process described in steps S1 to S3 in Figure 2 above. As a result, the additive manufacturing apparatus 100 creates the first layer SL1 on the base plate 144. The lower surface of layer SL1 is the surface to be processed SF.

[0045] In step S12, the additive manufacturing apparatus 100 repeats the additive manufacturing process described in steps S1 to S3 in Figure 2 above. As a result, the additive manufacturing apparatus 100 creates a second layer SL2 on the base plate 144. At this time, the additive manufacturing apparatus 100 makes the width ΔD2 of the second layer SL2 longer than the width ΔD1 of the processing surface SF in a direction parallel to the processing surface SF.

[0046] In step S13, the additive manufacturing apparatus 100 repeats the additive manufacturing process described in steps S1 to S3 in Figure 2 above. As a result, the additive manufacturing apparatus 100 creates a third layer SL3 on the base plate 144. At this time, the additive manufacturing apparatus 100 makes the width ΔD3 of the third layer SL3 longer than the width ΔD2 of the second layer in the direction parallel to the processing surface SF.

[0047] As described above, the additive processing apparatus 100 performs lamination processing such that the width of the workpiece portion WP in the direction parallel to the processing surface SF increases as it moves away from the processing surface SF. In the example in Figure 3, the outer shape of the workpiece portion WP is shown as a stepped structure, but the thickness of each layer is, for example, 20 to 100 μm, which is very thin. Therefore, the workpiece portion WP appears to have a tapered shape, with its width increasing as it moves away from the processing surface SF.

[0048] Figure 4 shows the workpiece W fabricated on the base plate 144 from the Y direction. Figure 5 shows a cross-section of the workpiece W along the VV line shown in Figure 4, viewed from the positive Z-axis side.

[0049] The workpiece W shown in Figures 4 and 5 is an example of a workpiece formed by additive manufacturing using the additive manufacturing device 100. In the example shown in Figures 4 and 5, the workpiece portion WP is manufactured using additive manufacturing so that it has a tapered shape. This makes it less likely for burrs to form on the workpiece W when it is separated from the base plate 144. The separation of the workpiece W from the base plate 144 is performed, for example, by a wire electrical discharge machine separate from the additive manufacturing device 100.

[0050] In the examples shown in Figures 4 and 5, the shape of the workpiece portion WP is shown to be a linear taper, but the shape of the workpiece portion WP is not limited to this. As other examples, the shape of the workpiece portion WP may be an exponential taper or a parabolic taper. Furthermore, the workpiece portion WP does not necessarily have to be tapered; it may have an inverted pyramidal shape in which the width increases as it moves away from the machining surface SF.

[0051] In the above description, an example where the planned machining surface SF is the contact surface between the workpiece W and the base plate 144 has been described. However, the planned machining surface SF is not limited to such a contact surface. The planned machining surface SF may be a portion to be machined by cutting in a post-process of the laminated machining. Examples of such a portion include, for example, a workpiece portion where milling is planned.

[0052] <D. Drive mechanism of the additional processing device 100> Next, referring to FIG. 6, the drive mechanism in the additional processing device 100 will be described. FIG. 6 is a diagram showing an example of the drive mechanism of the additional processing device 100.

[0053] As shown in FIG. 6, the additional processing device 100 includes a control unit 50, the above-described lifting mechanisms 130 and 140, the above-described reclaimer 150, the above-described laser irradiation mechanism 160, and drive units 210, 220, 230, and 240.

[0054] The control unit 50 controls various devices within the additional processing device 100. The device configuration of the control unit 50 is arbitrary. The control unit 50 may be composed of a single control unit or may be composed of a plurality of control units. As an example, the control unit 50 includes at least one of a CNC (Computer Numerical Control) and a PLC (Programmable Logic Controller).

[0055] The drive unit 210 is a drive mechanism for driving the above-described lifting mechanism 130. The drive unit 210 may be composed of a single drive unit or may be composed of a plurality of drive units. In the example of FIG. 6, the drive unit 210 is composed of a motor driver 211Z and a motor 212Z.

[0056] The motor driver 211Z sequentially receives input of the target position for the lifting mechanism 130 from the control unit 50 and outputs a current corresponding to the target position to the motor 212Z. As a result, the motor 212Z moves the lifting mechanism 130 to any position in the Z-axis direction. The motor 212Z may be an AC motor, a stepping motor, a servo motor, or any other type of motor.

[0057] The drive unit 220 is a drive mechanism for driving the lifting mechanism 140 described above. The drive unit 220 may consist of a single drive unit or multiple drive units. In the example in Figure 6, the drive unit 220 consists of a motor driver 221Z and a motor 222Z.

[0058] The motor driver 221Z sequentially receives input of the target position for the lifting mechanism 140 from the control unit 50 and outputs a current corresponding to the target position to the motor 222Z. As a result, the motor 222Z moves the lifting mechanism 140 to any position in the Z-axis direction. The motor 222Z may be an AC motor, a stepping motor, a servo motor, or any other type of motor.

[0059] The drive unit 230 is a drive mechanism for driving the recoater 150 described above. The drive unit 230 may consist of a single drive unit or multiple drive units. In the example shown in Figure 6, the drive unit 230 consists of a motor driver 231X and a motor 232X.

[0060] The motor driver 231X sequentially receives input of a target position for the recoater 150 from the control unit 50 and outputs a current corresponding to the target position to the motor 232X. As a result, the motor 232X moves the recoater 150 to any position in the X-axis direction. The motor 232X may be an AC motor, a stepping motor, a servo motor, or any other type of motor.

[0061] The drive unit 240 is a drive mechanism for rotationally driving the galvanometer mirrors 162A and 162B in the laser irradiation mechanism 160. The drive unit 240 may be composed of a single drive unit or a plurality of drive units. In the example of FIG. 6, the drive unit 240 is composed of motor drivers 241A and 241B and motors 242A and 242B.

[0062] The motor driver 241A sequentially receives an input of the target rotation angle or the target rotation speed of the galvanometer mirror 162A centered on the X-axis direction from the control unit 50, and outputs a current corresponding to the target rotation angle or the target rotation speed to the motor 242A. The motor 242A rotationally drives the galvanometer mirror 162A centered on the X-axis direction. The additional processing device 100 can irradiate the laser light LS at an arbitrary position in the X-axis direction by reflecting the laser light LS generated by the laser irradiation mechanism 160 with the galvanometer mirror 162A. The laser light LS reflected by the galvanometer mirror 162A is guided to the galvanometer mirror 162B.

[0063] The motor driver 241B sequentially receives an input of the target rotation angle or the target rotation speed of the galvanometer mirror 162B centered on the Y-axis direction from the control unit 50, and outputs a current corresponding to the target rotation angle or the target rotation speed to the motor 242B. The motor 242B rotationally drives the galvanometer mirror 162B centered on the Y-axis direction. The additional processing device 100 can irradiate the laser light LS at an arbitrary position in the Y-axis direction by reflecting the laser light LS generated by the laser irradiation mechanism 160 with the galvanometer mirror 162B.

[0064] <E. Hardware Configuration of Control Unit 50> Next, referring to FIG. 7, the hardware configuration of the control unit 50 shown in FIG. 6 will be described. FIG. 7 is a diagram showing an example of the hardware configuration of the control unit 50.

[0065] As described above, the control unit 50 may be a CNC or a PLC. Figure 7 shows the hardware configuration of the control unit 50 as a CNC.

[0066] The control unit 50 includes, for example, a control circuit 101, a ROM (Read Only Memory) 102, a RAM (Random Access Memory) 103, a communication interface 104, and an auxiliary storage device 120. These components are connected to the internal bus 109.

[0067] The control circuit 101 is comprised of, for example, at least one integrated circuit. The integrated circuit may consist of, for example, at least one CPU (Central Processing Unit), at least one GPU (Graphics Processing Unit), at least one ASIC (Application Specific Integrated Circuit), at least one FPGA (Field Programmable Gate Array), or a combination thereof.

[0068] The control circuit 101 controls the operation of the control unit 50 by executing various programs, such as the additive machining program 122. The additive machining program 122 is a program for realizing the various processes described herein. Based on receiving an execution command for the additive machining program 122, the control circuit 101 reads the additive machining program 122 from the ROM 102 into the RAM 103. The RAM 103 functions as working memory and temporarily stores various data necessary for the execution of the additive machining program 122.

[0069] The communication interface 104 is an interface for enabling communication with various devices. The additive processing device 100 communicates, for example, with various drive units (for example, the drive units 210, 220, 230, 240, etc.) for performing additive processing on a workpiece via the communication interface 104.

[0070] The auxiliary storage device 120 is, for example, a storage medium such as a hard disk or flash memory. The auxiliary storage device 120 stores the additive processing program 122 and three-dimensional data 124, etc. The additive processing program 122 is, for example, pre-generated from the three-dimensional data 124 of the workpiece W. The additive processing device 100 creates the workpiece W with the shape shown in the three-dimensional data 124 by executing the additive processing program 122.

[0071] The storage location for the additional processing program 122 and the three-dimensional data 124 is not limited to the auxiliary storage device 120, but may also be the storage area of ​​the control circuit 101 (for example, cache memory), ROM 102, RAM 103, or external devices (for example, a server).

[0072] Furthermore, the additive processing program 122 may be provided not as a standalone program, but incorporated as part of any other program. In this case, the various processes according to this embodiment are realized in cooperation with any other program. Even if a program does not include such modules, it does not deviate from the spirit of the additive processing program 122 according to this embodiment. Moreover, some or all of the functions provided by the additive processing program 122 may be realized by dedicated hardware. Furthermore, the control unit 50 may be configured in a form similar to a so-called cloud service, where at least one server executes part of the processing of the additive processing program 122.

[0073] <F.フローチャート> Next, with reference to Figure 8, the control flow of the additive processing device 100 will be described. Figure 8 is a flowchart showing the flow of the additive processing process by the additive processing device 100.

[0074] The process shown in Figure 8 is realized, for example, by the control unit 50 of the additive processing apparatus 100 executing the additive processing program 122 described above. In other aspects, part or all of the process may be performed by circuit elements or other hardware.

[0075] In step S110, the control unit 50 initializes a variable "N" for managing the number of layers of the workpiece W. "N" is a natural number. The initial value of "N" is "1".

[0076] In step S112, the control unit 50 raises the lifting mechanism 130 described above. The amount by which the lifting mechanism 130 rises is predetermined. This causes the metal powder material PM to be pushed out of the storage area AR1.

[0077] In step S114, the control unit 50 lowers the lifting mechanism 140. The lowering range of the lifting mechanism 140 is predetermined. This lowering range corresponds to the thickness of one layer of the workpiece W. As a result, a space where no metal powder material PM exists is formed in the processing area AR2.

[0078] In step S116, the control unit 50 drives the recoater 150, which is waiting at a predetermined position, to the negative side in the X-axis direction. At this time, the control unit 50 drives the recoater 150 so that, in a top view, the recoater 150 passes sequentially through the storage area AR1 and the processing area AR2. As a result, the metal powder material PM is supplied from the storage area AR1 to the processing area AR2. After that, the control unit 50 returns the recoater 150 to the predetermined waiting position.

[0079] In step S118, the control unit 50 controls the laser irradiation mechanism 160 according to the additive processing program 122 and irradiates the metal powder material PM spread in the processing area AR2 with laser light LS. At this time, the control unit 50 performs the lamination process such that the width of the workpiece portion WP, which is connected to the processing surface SF, increases as it moves away from the processing surface SF.

[0080] In step S120, the control unit 50 determines whether a predetermined termination condition has been met. For example, the termination condition is met when the variable "N" is greater than or equal to a predetermined value. If the control unit 50 determines that the predetermined termination condition has been met (YES in step S120), it terminates the process shown in Figure 8. Otherwise (NO in step S120), the control unit 50 switches control to step S122.

[0081] In step S122, the control unit 50 increments "N". That is, the control unit 50 adds 1 to "N". After that, the control unit 50 returns to step S112.

[0082] Based on the above, the control unit 50 performs the stacking process on the workpiece W. After the stacking process in the additive processing device 100 is completed on the workpiece W, a subsequent cutting or removal process is performed. The subsequent cutting or removal process may be performed in the additive processing device 100 or in a processing machine other than the additive processing device 100.

[0083] As an example, in a subsequent cutting process, wire electrical discharge machining is performed to separate the workpiece W from the base plate 144. In this case, the operator transports the workpiece W, which has been laminated by the additive processing device 100, together with the base plate 144 to the wire electrical discharge machining machine. The wire electrical discharge machining machine then performs wire electrical discharge machining along the planned processing surface SF of the workpiece W, separating the workpiece W from the base plate 144.

[0084] As another example, as a subsequent removal process, finishing is performed on the workpiece W. In this case, the operator transports the workpiece W, which has been completed by the additive processing device 100, to a machine tool. The machine tool then performs milling or other machining on the surface SF of the workpiece W to be processed, thereby shaping the workpiece W.

[0085] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of the present invention is indicated by the claims rather than by the foregoing description, and all modifications within the meaning and scope equivalent to the claims are intended to be included. [Explanation of Symbols]

[0086] 50 Control unit, 100 Add-on processing device, 101 Control circuit, 102 ROM, 103 RAM, 104 Communication interface, 109 Internal bus, 120 Auxiliary storage device, 122 Add-on processing program, 124 Three-dimensional data, 130 Lifting mechanism, 132 Wall surface, 140 Lifting mechanism, 142 Wall surface, 144 Base plate, 150 Recoater, 160 Laser irradiation mechanism, 162A Galvano mirror, 162B Galvano mirror, 210 Drive unit, 211Z Motor driver, 212Z Motor, 220 Drive unit, 221Z Motor driver, 222Z Motor, 230 Drive unit, 231X Motor driver, 232X Motor, 240 Drive unit, 241A Motor driver, 241B Motor driver, 242A Motor, 242B Motor, AR1 Storage area, AR2 processing area, LS laser light, PM metal powder material, SF processing surface, SL1 layer, SL2 layer, SL3 layer, W workpiece, WP workpiece area.

Claims

1. A method for additional machining of a workpiece, A step that lowers the floor surface of the workpiece processing area, The steps include lowering the floor of the processing area, then spreading metal powder material over the processing area, The steps include irradiating the metal powder material spread in the processing area with laser light, The process includes repeating the steps of lowering, laying, and irradiating to stack workpieces of a predetermined shape onto a plate attached to the floor surface, The aforementioned workpiece is After the completion of the stacking process of the workpiece of the predetermined shape, the surface to be cut or removed is to be processed, Including the workpiece portion connected to the surface to be machined, An additive processing method comprising the step of performing a lamination process such that the width of the workpiece portion in a direction parallel to the processing surface increases as it moves away from the processing surface.

2. The additional machining method according to claim 1, wherein the surface to be machined in the workpiece includes the contact surface with the plate.

3. The additional processing method according to claim 1 or 2, wherein the cutting process includes wire electrical discharge machining for separating the workpiece from the plate.

4. The additional machining method according to claim 1 or 2, wherein the workpiece portion has a tapered shape in which the width increases as it moves away from the surface to be machined.

5. The additional machining method according to claim 1 or 2, wherein the surface to be machined in the workpiece includes a surface machined by a milling cutter.

6. A recoater for spreading metal powder material in the workpiece processing area, A lifting mechanism configured to allow the floor surface of the aforementioned processing area to be raised and lowered, A plate configured to be detachably attached to the floor surface, An irradiation mechanism capable of performing stacking processing of the workpiece by irradiating a laser beam onto a metal powder material spread in the processing area, The system includes a control unit that can perform stacking processing of a workpiece of a predetermined shape in the processing area by repeatedly supplying metal powder material to the processing area using the recoater, lowering the floor surface using the lifting mechanism, and irradiating with laser light using the irradiation mechanism, The aforementioned workpiece is After the completion of the stacking process of the workpiece of the predetermined shape, the surface to be cut or removed is to be processed, Including the workpiece portion connected to the surface to be machined, The control unit is an additive processing device that performs lamination processing such that the width of the workpiece portion in a direction parallel to the processing surface increases as it moves away from the processing surface.

7. An additional machining program for a workpiece, The aforementioned additional processing program is programmed into a computer. A step that lowers the floor surface of the workpiece processing area, The steps include lowering the floor of the processing area, then spreading metal powder material over the processing area, The steps include irradiating the metal powder material spread in the processing area with laser light, By repeating the steps of lowering, laying, and irradiating, the step of stacking workpieces of a predetermined shape onto the plate attached to the floor surface is performed. The aforementioned workpiece is After the completion of the stacking process of the workpiece of the predetermined shape, the surface to be cut or removed is to be processed, Including the workpiece portion connected to the surface to be machined, An additive machining program comprising the step of performing a stacking process such that the width of the workpiece portion in a direction parallel to the processing surface increases as it moves away from the processing surface.

Images