Machining method, machining device, and machining program

Abstract

To provide a machining technique capable of heat-treating a workpiece molded by a DED method.SOLUTION: The machining method implemented by a machining device capable of performing an addition process of feeding a powder material while applying a laser beam to a workpiece and a work removal process using a tool comprises the steps of: forming an unnecessary part in the workpiece through the addition process or the removal process; executing the addition process for a place of the workpiece different from the unnecessary part; applying the laser beam to the unnecessary part after completion of the addition process; and removing the unnecessary part through the removal process after completion of the application step.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present disclosure relates to a workpiece machining method, a workpiece machining device, and a workpiece machining program. [Background technology]

[0002] JP2020-530528A (Patent Document 1) discloses an additive manufacturing device that performs additive processing using the SLM (Selective Laser Melting) method. The SLM method is a method of realizing additive manufacturing by irradiating a spread metal powder with laser light and locally melting and solidifying the metal powder.

[0003] The additive manufacturing device disclosed in Patent Document 1 includes a heat source such as an infrared lamp in addition to an energy source for irradiating a laser beam. The heat source heats the part irradiated with the laser beam. In this way, the additive manufacturing device performs heat treatment on the additively manufactured object. Heat treatment is a process that changes the properties of the additively manufactured object by heating and cooling. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Special Publication No. 2020-530528 Summary of the Invention [Problem to be solved by the invention]

[0005] In addition to the SLM method, there is also the Directed Energy Deposition (DED) method as an additive manufacturing method. The DED method is a method of manufacturing a workpiece by melting and layering supplied powder material with laser light. There is a demand for processing technology that can perform heat treatment on workpieces manufactured by this DED method. [Means for solving the problem]

[0006] In one example of the present disclosure, a processing method is provided that is executed by a processing device capable of performing additive processing of supplying a powder material while irradiating a workpiece with a laser beam and removing the workpiece with a tool. The processing method includes a step of forming an unnecessary portion on the workpiece by the additive processing or the removing processing, a step of performing the additional processing on a portion of the workpiece different from the unnecessary portion, a step of irradiating the unnecessary portion with the laser beam after the step of performing the additional processing is completed, and a step of removing the unnecessary portion by the removing processing after the step of irradiating is completed.

[0007] In one example of the present disclosure, during the irradiating step, the supply of the powder material is stopped.

[0008] In one example of the present disclosure, the step of performing the additional processing on the location includes performing a coating process to coat the powder material on the surface of the workpiece.

[0009] In one example of the present disclosure, the irradiating step is performed a predetermined time after additional processing on the area is completed.

[0010] In one example of the present disclosure, in the irradiating step, the laser light is irradiated onto the unnecessary portion while an irradiation point of the laser light is moved.

[0011] In one example of the present disclosure, in the irradiating step, the laser head is driven such that an irradiation point of the laser light on the unnecessary portion repeatedly passes along a predetermined path.

[0012] In one example of the present disclosure, in the irradiating step, the laser head is driven such that an irradiation point of the laser light on the unnecessary portion repeatedly passes along a predetermined path.

[0013] In one example of the present disclosure, in the irradiating step, the laser light is irradiated onto the unnecessary portion such that an irradiation point of the laser light on the unnecessary portion is different from a focus of the laser light.

[0014] In another example of the present disclosure, a processing device is provided that can perform additional processing of supplying a powder material while irradiating a workpiece with a laser beam, and removal processing of the workpiece using a tool. The processing device includes a control unit for controlling the processing device. The control unit executes a process of forming an unnecessary portion in the workpiece by the additional processing or the removal processing, a process of performing the additional processing on a portion of the workpiece different from the unnecessary portion, a process of irradiating the unnecessary portion with the laser beam after the process of performing the additional processing is completed, and a process of removing the unnecessary portion by the removal processing after the process of irradiating is completed.

[0015] In another example of the present disclosure, a processing program is provided that is executed by a processing device capable of performing additive processing of supplying a powder material while irradiating a workpiece with a laser beam and removing the workpiece with a tool. The processing program causes the processing device to execute a step of forming an unnecessary portion in the workpiece by the additive processing or the removing processing, a step of performing the additional processing on a portion of the workpiece different from the unnecessary portion, a step of irradiating the unnecessary portion with the laser beam after the step of performing the additional processing is completed, and a step of removing the unnecessary portion by the removing processing after the step of irradiating is completed.

[0016] The above and other objects, features, aspects and advantages of the present invention will become apparent from the following detailed description of the invention taken in conjunction with the accompanying drawings. [Brief description of the drawings]

[0017] [Figure 1] FIG. 2 is a diagram showing an example of the appearance of a processing device. [Diagram 2] FIG. 2 is a diagram illustrating an example of a device configuration of a processing device. [Diagram 3] Shows a cross-sectional view of the laser head during additional processing. [Figure 4] It is a diagram showing the processing steps by the processing apparatus in chronological order. [Diagram 5] It is a diagram showing the processing steps by the processing apparatus in chronological order. [Figure 6] It is a diagram showing an example of the drive mechanism of the processing apparatus. [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 processing steps by the processing apparatus. [Figure 9] It is a diagram showing the workpiece used in the experiment.

Embodiments for Carrying Out the Invention

[0018] 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. Note that each embodiment and each modification described below may be selectively combined as appropriate.

[0019] <A. Appearance of the Processing Apparatus 100> First, with reference to FIG. 1, the processing apparatus 100 according to the embodiment will be described. FIG. 1 is a diagram showing an example of the appearance of the processing apparatus 100.

[0020] The processing apparatus 100 is a processing machine capable of additive processing (AM (Additive manufacturing) processing) in which a powder material is supplied while irradiating a workpiece with laser light and subtractive processing (SM (Subtractive manufacturing)) of the workpiece using a tool. The subtractive processing function of the processing apparatus 100 includes, for example, at least one of a milling function and a turning function using a fixed tool.

[0021] The processing apparatus 100 includes, for example, a cover body 130 and an operation panel 200.

[0022] The cover body 130 is a mechanism for protecting the components provided inside the processing device 100. A door DR is provided on the cover body 130. The door DR is, for example, a slide-type door. The door DR may be configured to be openable and closable by a drive source such as a motor, or may be configured to be openable and closable manually.

[0023] The operation panel 200 is a general-purpose computer and has a display for displaying various pieces of information related to processing. The display is, for example, a liquid crystal display, an organic EL (Electro Luminescence) display, or other display device. Further, the display is provided with a touch panel and accepts various operations on the processing device 100 by touch operations.

[0024] <B. Device Configuration of Processing Device 100> Next, with reference to FIG. 2, the device configuration of the processing device 100 will be described. FIG. 2 is a diagram showing an example of the device configuration of the processing device 100.

[0025] As described above, the processing device 100 includes a cover body 130. The cover body 130 forms the appearance of the processing device 100 and partitions and forms a processing area AR for performing additional processing on the workpiece W.

[0026] Further, the processing device 100 includes a bed 11, a tool rest 16, a workpiece spindle 22, a steady rest 25, a tool spindle 30, and a laser head 140.

[0027] For the sake of convenience of explanation, hereinafter, the rotational axis direction of the workpiece spindle 22 is also referred to as the "Z-axis direction". The Z-axis direction is parallel to the axes AX1 to AX3 shown in FIG. 2. Also, one direction on the horizontal plane orthogonal to the Z-axis direction is also referred to as the "X-axis direction". The direction orthogonal to both the X-axis direction and the Z-axis direction is referred to as the "Y-axis direction". In the example of FIG. 2, the Y-axis direction corresponds to the direction of gravity.

[0028] The bed 11 is a base member for supporting various devices provided in the processing device 100. In the example of Fig. 2, the bed 11 supports the tool rest 16, the work spindle 22, the tailstock 25, and the laser head 140. The bed 11 is installed on the floor of a factory or the like. The bed 11 is made of metal such as cast iron.

[0029] The tool rest 16 has a turret 18. The turret 18 is configured to be rotatable about an axis AX1. The turret 18 holds a plurality of tools at intervals in the circumferential direction about the axis AX1. The tool rest 16 is also configured to be movable in the X-axis direction and the Y-axis direction by various driving mechanisms such as a motor. The tool rest 16 performs turning by bringing a fixed tool held by the turret 18 into contact with a workpiece W that is rotationally driven by a workpiece spindle 22.

[0030] The work spindle 22 is configured to be rotatable while holding the workpiece W. More specifically, the work spindle 22 is provided with a chuck mechanism 23. The chuck mechanism 23 is a mechanism for fixing the workpiece W to the work spindle 22. The work spindle 22 is also configured to be rotatable about an axis AX2 that is aligned with the axial direction of the work spindle 22.

[0031] The tailstock 25 is configured to be movable along the axis AX3 by various driving mechanisms such as a motor. As a result, the tailstock 25 supports the long workpiece W from the side opposite to the workpiece spindle 22. Typically, the axis AX3 is coaxial with the axis AX2. The tailstock 25 is also configured to be rotatable about the axis AX3.

[0032] A second work spindle (not shown) may be provided instead of the tailstock 25. The second work spindle is provided opposite the work spindle 22 and is configured to be able to hold the work W from the side opposite the work spindle 22.

[0033] The tool spindle 30 is provided, for example, at a position higher than the work spindle 22 and the steady rest 25. Further, the tool spindle 30 is configured to be detachable from the tool or the laser head 140. FIG. 2 shows an example in which the laser head 140 is attached to the tool spindle 30.

[0034] The attachment and detachment of the laser head 140 to and from the tool spindle 30 is realized by a dedicated attachment and detachment mechanism (not shown) for the laser head 140, which is different from, for example, an automatic tool changer (ATC: Automatic Tool Changer) used for automatic tool change. When performing additional processing on the work W, the processing apparatus 100 attaches the laser head 140 to the tool spindle 30. On the other hand, when performing removal processing on the work W, the processing apparatus 100 attaches a tool to the tool spindle 30.

[0035] As an example of the removal processing, there is milling in which a rotating tool is brought into contact with the work W fixed to the work spindle 22. As another example of the removal processing, there is turning in which a tool is pressed against the work W rotating about the axis AX2.

[0036] The laser head 140 performs additive processing by the DED method while being attached to the tool spindle 30. As a mechanism for realizing the additive processing, the laser head 140 includes a head body 142 and a laser nozzle 146.

[0037] Powder material is supplied to the head body 142 via a cable (not shown). The supplied powder material may be metal powder, resin powder, or other types of powder that melt when irradiated with laser light.

[0038] The laser nozzle 146 irradiates the work W with laser light and defines the laser light irradiation region on the work W. The powder material supplied to the laser head 140 is discharged toward the work W through the laser nozzle 146.

[0039] <C. Additive Processing> Next, with reference to FIG. 3, additional processing by the laser head 140 will be described in more detail. FIG. 3 shows a cross-sectional view of the laser head 140 during additional processing.

[0040] While at least one of the laser head 140 and the workpiece W is being driven, the laser head 140 irradiates the surface of the workpiece W with the laser light LS. As an example, while moving in the axial direction of the workpiece spindle 22 (i.e., the Z-axis direction), the laser head 140 irradiates the rotating workpiece W with the laser light LS. As a result, the workpiece W melts at the irradiated portion of the laser light LS, and a molten pool MP is formed on the surface of the workpiece W.

[0041] In parallel, the laser head 140 supplies the powder material PM to the molten pool MP. The powder material PM is guided to the molten pool MP by the gas GS ejected from the laser head 140. As a result, the powder material PM melts and liquefies in the molten pool MP. Then, as the molten pool MP solidifies, a layer SL is formed on the workpiece W. Note that the gas GS also functions as a shielding gas and prevents oxidation of the workpiece W, which is a laminate.

[0042] The processing apparatus 100 can realize various additional processes by controlling the laser head 140. Examples of additional processes include laminating and coating. Laminating is a process of stacking layers SL on the workpiece W. Coating is a process of covering the surface of the workpiece W with the layer SL.

[0043] <D. Heat treatment of workpiece> Next, with reference to FIGS. 4 and 5, heat treatment of the workpiece by the processing apparatus 100 will be described. FIGS. 4 and 5 are diagrams showing the processing steps by the processing apparatus 100 in chronological order.

[0044] FIGS. 4 and 5 show the workpiece W to be processed. The type of the workpiece W is arbitrary. In the examples of FIGS. 4 and 5, a cylindrical workpiece W is shown. As another example, the workpiece W may be a cylindrical shaft.

[0045] In step S1, the processing device 100 forms an unnecessary portion PB in a base material portion PA of the workpiece W. The unnecessary portion PB refers to an unnecessary portion that will ultimately be removed from the workpiece W. The unnecessary portion PB may be formed in the workpiece W by an additive process, or may be formed in the workpiece W by a subtractive process. In the example of Fig. 4, the processing device 100 forms the unnecessary portion PB in the base material portion PA by supplying a powder material PM and irradiating it with a laser beam LS.

[0046] Next, in step S2, the processing device 100 performs additional processing on an additional processing portion PC of the workpiece W that is different from the unnecessary portion PB. The additional processing is executed, for example, according to an additional processing program that is designed in advance. In the example of Fig. 4, a coating process is executed to coat the surface of the workpiece W with the powder material PM. Note that instead of the coating process, a lamination process may be executed to build up layers.

[0047] Next, in step S3, the processing device 100 irradiates the unnecessary portion PB formed in step S1 with laser light LS. As a result, heat is transferred in the order of the unnecessary portion PB, the base material portion PA, and the additional processing portion PC, thereby realizing heat treatment of the additional processing portion PC. The heat treatment changes the properties of the additional processing portion PC. The properties that are changed include hardness, strength, and tenacity.

[0048] Next, in step S4, the processing device 100 removes the unnecessary portion PB from the workpiece W by removal processing. The removal processing of the unnecessary portion PB may be realized by a tool attached to the tool spindle 30, or the unnecessary portion PB may be removed by a tool attached to the above-mentioned tool rest 16 (see FIG. 2). In the example of FIG. 5, the laser head 140 is removed from the tool spindle 30, and then the tool T is attached to the tool spindle 30, and the unnecessary portion PB is removed by the tool T.

[0049] As described above, the processing device 100 heats the additional processing area PC through the unnecessary portion PB by irradiating the laser light LS to the unnecessary portion PB. Since the laser light LS is not directly irradiated to the base material portion PA or the additional processing area PC, the heat treatment of the additional processing area PC can be realized without deteriorating the processing quality of the necessary portion of the workpiece W.

[0050] Such heat treatment is particularly effective when additional processing is performed using high-hardness materials such as high-speed steel. If heat treatment is not performed, the hardness of the additional processing area PC may be insufficient, but in the processing apparatus 100 according to the embodiment, high-temperature heat treatment is achieved by irradiating the laser light LS in step S3. The hardness of the additional processing area PC is sufficiently improved. In addition, the toughness of the additional processing area PC is also improved, making the additional processing area PC less likely to crack.

[0051] Moreover, in the processing apparatus 100 according to the embodiment, the additional processing of the workpiece W and the heat treatment of the workpiece W are realized in the same machine. Therefore, the worker can perform the heat treatment of the workpiece W without removing the workpiece W from the processing apparatus 100. This significantly improves the work efficiency.

[0052] In the above-mentioned step S3, the processing apparatus 100 may perform the heat treatment while supplying the powder material PM to the unnecessary portion PB, or may perform the heat treatment by stopping the supply of the powder material PM to the unnecessary portion PB. Preferably, the processing apparatus 100 irradiates only the laser light LS to the unnecessary portion PB and stops the supply of the powder material PM. This allows the processing apparatus 100 to reduce the amount of powder material PM used.

[0053] Also, preferably, the heat treatment in step S3 is performed after a predetermined time has elapsed since the completion of the additional processing in step S2. This allows the processing device 100 to perform the heat treatment after cooling the workpiece W heated by the additional processing in step S2. As a result, the hardness and toughness of the additional processing portion PC are further improved.

[0054] The time from the completion of the additional processing in step S2 to the start of the heat treatment in step S3 may be set in advance or may be set arbitrarily by the user. The time is set so that the temperature of the workpiece W decreases to a predetermined temperature. The predetermined temperature is, for example, the room temperature in the processing apparatus 100.

[0055] Preferably, during the heat treatment in step S3, the processing apparatus 100 irradiates the unnecessary portion PB with the laser light LS while moving the irradiation point of the laser light LS. At this time, if the irradiation point of the laser light LS with respect to the unnecessary portion PB moves relatively, the laser head 140 may be driven, the workpiece W may be driven, or the irradiation direction of the laser light LS may be changed by a galvanometer mirror or the like.

[0056] In one aspect, the laser light LS is irradiated onto the unnecessary portion PB while driving the laser head 140. This prevents the irradiation of the laser light LS from concentrating on one point on the unnecessary portion PB, and the processing apparatus 100 can prevent the unnecessary portion PB from melting.

[0057] At this time, the laser head 140 is driven so that the irradiation point of the laser light LS on the unnecessary portion PB repeatedly passes through a predetermined path. The shape of the path is arbitrary. As an example, the shape of the path may be a circle, an ellipse, a rectangle, or another shape. This allows the laser head 140 to heat the entire workpiece W more uniformly.

[0058] Preferably, the unnecessary portion PB is formed as far away as possible from the additional processing location PC. As an example, when the additional processing location PC is on a first surface of the workpiece W, the unnecessary portion PB is formed on a second surface of the workpiece W. The second surface may be a surface perpendicular to the first surface, or may be a surface opposite to the first surface. In this way, by separating the unnecessary portion PB as far away as possible from the additional processing location PC, heat is uniformly transferred to the additional processing location PC during the heat treatment in step S3, and the properties of the additional processing location PC can be uniformly changed.

[0059] Also, during the heat treatment in step S3, the processing apparatus 100 may irradiate the laser beam LS so that the focal point of the laser beam LS is located on the surface of the unnecessary portion PB, or may irradiate the laser beam LS so that the focal point of the laser beam LS is not located on the surface of the unnecessary portion PB. Preferably, the processing apparatus 100 irradiates the unnecessary portion PB with the laser beam LS such that the irradiation point of the laser beam LS on the unnecessary portion PB is different from the focal point of the laser beam LS. Thereby, the processing apparatus 100 can prevent the workpiece W from becoming too hot during the heat treatment.

[0060] Note that, in the above description, the example in which the formation process of the unnecessary portion PB in step S1 is executed before the start of the additional processing in step S2 has been described, but the timing of forming the unnecessary portion PB is not limited to this. As an example, the formation process of the unnecessary portion PB in step S1 may be executed after the completion of the additional processing in step S2.

[0061] <E. Driving mechanism of the processing apparatus 100> Next, with reference to FIG. 6, the driving mechanism in the processing apparatus 100 will be described. FIG. 6 is a diagram showing an example of the driving mechanism of the processing apparatus 100.

[0062] As shown in FIG. 6, the processing apparatus 100 includes a control unit 50 and driving units 210, 220, 230A, 230B, 240.

[0063] The control unit 50 controls various devices in the processing apparatus 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).

[0064] The driving unit 210 is a driving mechanism for rotating the work spindle 22. The driving unit 210 may be composed of a single driving unit, or may be composed of multiple driving units. In the example of Fig. 6, the driving unit 210 is composed of a motor driver 211C and a motor 212C.

[0065] The motor driver 211C sequentially receives input of the target rotation angle or the target rotation speed of the work spindle 22 from the control unit 50, and outputs a current according to the target rotation angle or the target rotation speed to the motor 212C. As a result, the work held by the work spindle 22 rotates about the Z-axis direction as the center of rotation. The motor 212C may be an AC motor, a stepping motor, a servo motor, or any other type of motor.

[0066] The driving unit 220 is a driving mechanism for driving the tailstock 25. The driving unit 220 may be composed of a single driving unit, or may be composed of multiple driving units. In the example of Fig. 6, the driving unit 220 is composed of a motor driver 221Z and a motor 222Z.

[0067] The motor driver 221Z sequentially receives input of target positions for the work spindle 22 from the control unit 50, and outputs a current corresponding to the target positions to the motor 222Z. This causes the motor 222Z to move the tailstock 25 to an arbitrary 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.

[0068] The driving unit 230A is a driving mechanism for moving the position of the tool spindle 30. The above-mentioned laser head 140 is driven by being attached to the tool spindle 30. The driving unit 230A may be composed of a single driving unit, or may be composed of a plurality of driving units. In the example of Fig. 6, the driving unit 230A is composed of motor drivers 231X to 231Z and motors 232X to 232Z.

[0069] The motor driver 231X sequentially receives input of target positions of the tool spindle 30 in the X-axis direction from the control unit 50, and outputs a current corresponding to the target positions to the motor 232X. As a result, the motor 232X drives the tool spindle 30 to an arbitrary 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.

[0070] The motor driver 231Y sequentially receives input of target positions of the tool spindle 30 in the Y-axis direction from the control unit 50, and outputs a current corresponding to the target positions to the motor 232Y. As a result, the motor 232Y drives the tool spindle 30 to an arbitrary position in the Y-axis direction. The motor 232Y may be an AC motor, a stepping motor, a servo motor, or any other type of motor.

[0071] The motor driver 231Z sequentially receives input of target positions of the tool spindle 30 in the Z-axis direction from the control unit 50, and outputs a current corresponding to the target positions to the motor 232Z. As a result, the motor 232Z moves the tool spindle 30 to an arbitrary position in the Z-axis direction. The motor 232Z may be an AC motor, a stepping motor, a servo motor, or any other type of motor.

[0072] The driving unit 230B is a driving mechanism for rotationally driving the tool spindle 30. The driving unit 230B may be composed of a single driving unit, or may be composed of a plurality of driving units. In the example of Fig. 6, the driving unit 230B is composed of motor drivers 231A, 231B and motors 232A, 232B.

[0073] The motor driver 231A sequentially receives input of a target rotation angle or a target rotation speed of the tool spindle 30 centered on the X-axis direction from the control unit 50, and outputs a current according to the target rotation angle or the target rotation speed to the motor 232A. The motor 232A drives the tool spindle 30 to rotate around the X-axis direction. The motor 232A may be an AC motor, a stepping motor, a servo motor, or any other type of motor.

[0074] The motor driver 231B sequentially receives an input of a target rotation angle or a target rotation speed of the tool spindle 30 about the axial direction of the tool spindle 30 as a rotation center from the control unit 50, and outputs a current according to the target rotation angle or the target rotation speed to the motor 232B. The motor 232B drives and rotates the tool spindle 30 about the axial direction of the tool spindle 30 as a rotation center. The motor 232B may be an AC motor, a stepping motor, a servo motor, or another type of motor.

[0075] The driving unit 240 is a driving mechanism for driving the tool rest 16 and the turret 18. The driving unit 240 may be composed of a single driving unit, or may be composed of multiple driving units. In the example of Fig. 6, the driving unit 240 is composed of motor drivers 241C, 241Y, and 241Z, and motors 242C, 242Y, and 242Z.

[0076] The motor driver 241C receives an input of a target value for the rotation angle of the turret 18 about the Z-axis direction, and outputs a current according to the target value to the motor 242C. In this way, the motor driver 241C controls the rotation angle of the turret 18 about the Z-axis direction as the center of rotation. The motor 242C may be an AC motor, a stepping motor, a servo motor, or any other type of motor.

[0077] The motor driver 241Y sequentially receives the input of the target position of the tool post 16 in the Y-axis direction from the control unit 50, and outputs a current corresponding to the target position to the motor 242Y. Thereby, the motor 242Y moves the tool post 16 to an arbitrary position in the Y-axis direction. The motor 242Y may be an AC motor, a stepping motor, a servo motor, or other types of motors.

[0078] The motor driver 241Z sequentially receives the input of the target position of the tool post 16 in the Z-axis direction from the control unit 50, and outputs a current corresponding to the target position to the motor 242Z. Thereby, the motor 242Z moves the tool post 16 to an arbitrary position in the Z-axis direction. The motor 242Z may be an AC motor, a stepping motor, a servo motor, or other types of motors.

[0079] <F. Hardware Configuration of Control Unit 50> Next, with reference 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.

[0080] As described above, the control unit 50 may be a CNC or a PLC. FIG. 7 shows the hardware configuration of the control unit 50 as a CNC.

[0081] 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 an internal bus 109.

[0082] The control circuit 101 is configured, for example, by at least one integrated circuit. The integrated circuit may be configured, for example, by at least one central processing unit (CPU), at least one graphics processing unit (GPU), at least one application specific integrated circuit (ASIC), at least one field programmable gate array (FPGA), or a combination thereof.

[0083] The control circuit 101 controls the operation of the control unit 50 by executing various programs such as a machining program 122. The machining program 122 is a program for realizing various processes described in this specification. Based on receiving an execution command for the machining program 122, the control circuit 101 reads the machining program 122 from the ROM 102 to the RAM 103. The RAM 103 functions as a working memory and temporarily stores various data required for executing the machining program 122.

[0084] The communication interface 104 is an interface for realizing communication with various devices. The processing device 100 communicates with various drive units (e.g., the above-mentioned drive units 210, 220, 230A, 230B, 240, etc.) for realizing additional processing of the workpiece, for example, via the communication interface 104.

[0085] The auxiliary storage device 120 is a storage medium such as a hard disk or a flash memory. The auxiliary storage device 120 stores a machining program 122 and the like. The storage location of the machining program 122 is not limited to the auxiliary storage device 120, and may be stored in a memory area (e.g., cache memory) of the control circuit 101, the ROM 102, the RAM 103, an external device (e.g., a server), or the like.

[0086] Further, the machining program 122 may be provided by being incorporated into a part of any program instead of being a single program. In this case, various processes according to the present embodiment are realized in cooperation with any program. Even a program that does not include such a part of the module does not deviate from the gist of the machining program 122 according to the present embodiment. Further, part or all of the functions provided by the machining program 122 may be realized by dedicated hardware. Further, the control unit 50 may be configured in a form such as a so-called cloud service in which at least one server executes a part of the processing of the machining program 122.

[0087] <G. Control Flow> Next, with reference to FIG. 8, the control flow of the machining apparatus 100 will be described. FIG. 8 is a flowchart showing the flow of the machining process by the machining apparatus 100.

[0088] The process shown in FIG. 8 is realized by the control unit 50 of the machining apparatus 100 executing the above-described machining program 122. In other aspects, part or all of the process may be executed by circuit elements or other hardware.

[0089] In step S110, the control unit 50 determines whether an execution instruction for additional machining has been received. The execution instruction for additional machining is, for example, a command to attach the laser head 140 to the tool spindle 30, or a command to move the tool spindle 30 to which the laser head 140 is attached before the laser beam LS is emitted. When the control unit 50 determines that an execution instruction for additional machining has been received (YES in step S110), the control is switched to step S112. Otherwise (NO in step S110), the control unit 50 executes the process of step S110 again.

[0090] In step S112, the control unit 50 controls the laser head 140 to form an unnecessary portion PB in the base material portion PA of the workpiece W. The unnecessary portion PB may be formed in the workpiece W by an additive process or may be formed in the workpiece W by a subtractive process.

[0091] In step S114, the control unit 50 controls the laser head 140 to perform additional processing on the additional processing portion PC of the workpiece W that is different from the unnecessary portion PB. The additional processing is executed, for example, according to a pre-designed additional processing program.

[0092] In step S120, the control unit 50 determines whether a predetermined time has elapsed since the additional machining has been completed. As an example, the control unit 50 determines that the additional machining of the workpiece has been completed based on the completion of execution of the additional machining program. If the control unit 50 determines that a predetermined time has elapsed since the additional machining has been completed (YES in step S120), it switches control to step S122. If not (NO in step S120), the control unit 50 executes the process of step S120 again.

[0093] In step S122, the control unit 50 performs heat treatment of the workpiece W. More specifically, the control unit 50 controls the laser head 140 to irradiate the laser light LS to the unnecessary portion PB formed in step S112. At this time, preferably, the control unit 50 causes the laser head 140 to irradiate the laser light LS in a state where the supply of the powder material PM is stopped. The heat treatment in step S122 is performed for a predetermined time.

[0094] In step S130, the control unit 50 determines whether or not a predetermined time has elapsed since the heat treatment in step S122 is completed. If the control unit 50 determines that the predetermined time has elapsed since the heat treatment in step S122 is completed (YES in step S130), the control unit 50 switches control to step S132. If not (NO in step S130), the control unit 50 executes the process of step S130 again.

[0095] In step S132, the control unit 50 removes the laser head 140 from the tool spindle 30 and attaches the tool T to the tool spindle 30. Thereafter, the control unit 50 controls the tool spindle 30 to perform machining for removing the unnecessary portion PB.

[0096] <H. Experimental Results> The inventor confirmed the effectiveness of the heat treatment according to the above-described embodiment through experiments. Hereinafter, with reference to FIG. 9, the results of the experiment will be described. FIG. 9 is a view showing the workpiece W used in this experiment.

[0097] The workpiece W used in this experiment was composed of a base material portion PA, an unnecessary portion PB, and an additional machining portion PC. The base material portion PA of the workpiece W was fixed by the fixing jigs JA and JB. The unnecessary portion PB was formed on one surface of the base material portion PA. The additional machining portion PC was formed on the other surface of the base material portion PA by coating with powder high-speed steel.

[0098] In this experiment, the inventor measured the Vickers hardness of the additional machining portion PC when the above heat treatment was not performed and the Vickers hardness of the additional machining portion PC when the above heat treatment was performed. The Vickers hardness of the additional machining portion PC when the above heat treatment was not performed was about 860 HV. On the other hand, the Vickers hardness of the additional machining portion PC when the above heat treatment was performed was 950 HV to 980 HV. Thereby, the inventor confirmed that the hardness of the additional machining portion PC was improved by the above heat treatment.

[0099] The embodiments disclosed this time should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is shown not by the above description but by the claims, and it is intended that all modifications within the meaning and scope equivalent to the claims are included.

Description of Reference Numerals

[0100] 11 bed, 16 tool rest, 18 turret, 22 work spindle, 23 chuck mechanism, 25 tailstock, 30 tool spindle, 50 control unit, 100 machining device, 101 control circuit, 102 ROM, 103 RAM, 104 communication interface, 109 internal bus, 120 auxiliary storage device, 122 machining program, 130 cover body, 140 laser head, 142 head body, 146 laser nozzle, 200 operation panel, 210 drive unit, 211C motor driver, 212C motor, 220 drive unit, 221Z motor driver, 222Z motor, 230A drive unit, 230B drive unit, 231A motor driver, 231B motor driver, 231X motor driver, 231Y motor driver, 231Z motor driver, 232A Motor, 232B motor, 232X motor, 232Y motor, 232Z motor, 240 drive unit, 241C motor driver, 241Y motor driver, 241Z motor driver, 242C motor, 242Y motor, 242Z motor, AR machining area, AX1 axis, AX2 axis, AX3 axis, DR door, GS gas, JA fixing jig, JB fixing jig, LS laser light, MP molten pool, PA base material part, PB unnecessary part, PC additional machining area, PM powder material, SL layer, T tool, W workpiece.

Claims

1. A processing method performed by a processing device capable of performing additive processing of supplying a powder material to a workpiece while irradiating the workpiece with a laser beam, and removing the workpiece using a tool, the method comprising: forming an unnecessary portion on the workpiece by the additive processing or the subtractive processing; performing the additional processing on a portion of the workpiece different from the unnecessary portion; a step of irradiating the unnecessary portion with the laser light after the step of performing the additional processing is completed; After completion of the irradiating step, removing the unnecessary portion by the removal processing.

2. The processing method according to claim 1 , wherein the supply of the powder material is stopped during the irradiating step.

3. The processing method according to claim 1 or 2, wherein in the step of performing the additional processing on the portion, a coating process is performed to coat the surface of the workpiece with the powder material.

4. The processing method according to claim 1 or 2, wherein the irradiating step is executed after a predetermined time has elapsed since additional processing on the portion is completed.

5. 3. The processing method according to claim 1, wherein in the irradiating step, the laser light is irradiated to the unnecessary portion while an irradiation point of the laser light is moved.

6. The processing device includes a laser head for performing the additional processing, The processing method according to claim 5 , wherein in the irradiating step, the laser light is irradiated to the unnecessary portion while the laser head is driven.

7. The processing method according to claim 6 , wherein in the irradiating step, the laser head is driven so that an irradiation point of the laser light on the unnecessary portion repeatedly passes along a predetermined path.

8. 3. The processing method according to claim 1, wherein in the irradiating step, the laser light is irradiated onto the unnecessary portion such that an irradiation point of the laser light on the unnecessary portion is different from a focus of the laser light.

9. A processing apparatus capable of performing additive processing of supplying a powder material to a workpiece while irradiating the workpiece with a laser beam, and removing the workpiece using a tool, A control unit for controlling the processing device, The control unit is A process of forming an unnecessary portion on the workpiece by the additive process or the subtractive process; A process of performing the additional processing on a portion of the workpiece other than the unnecessary portion; a process of irradiating the unnecessary portion with the laser light after the process of performing the additional processing is completed; and after completion of the irradiation process, performing a process of removing the unnecessary portion by the removal process.

10. A processing program executed by a processing device capable of performing additive processing of supplying a powder material while irradiating a workpiece with a laser beam and removing the workpiece using a tool, The processing program is for the processing device. forming an unnecessary portion on the workpiece by the additive processing or the subtractive processing; performing the additional processing on a portion of the workpiece different from the unnecessary portion; a step of irradiating the unnecessary portion with the laser light after the step of performing the additional processing is completed; and a step of removing the unnecessary portion by the removal processing after the irradiation step is completed.

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