Additive manufacturing apparatus, additive manufacturing method, and additive manufacturing program

Abstract

To provide a technique for improving additional machining accuracy of a workpiece more than before.SOLUTION: The additive manufacturing apparatus includes a laser head configured to supply a powder material to a workpiece and irradiate the workpiece with a laser beam to perform additive manufacturing on the workpiece, a driver configured to drive the laser head, and a controller configured to control the additive manufacturing apparatus. The controller drives the laser head to perform a process of additively manufacturing an additive portion having a desired shape on the workpiece. The additively manufacturing includes driving the laser head such that an optical axis of the laser head is directed from outside of the additional portion toward the end portion in the top view when additively manufacturing the end portion in the horizontal direction of the additional portion.SELECTED DRAWING: Figure 10

Description

[Technical Field]

[0001] The present disclosure relates to an additive processing device, an additive processing method, and an additive processing program. [Background technology]

[0002] Japanese Patent Application Laid-Open Publication No. 2023-125537 (Patent Document 1) discloses a processing machine capable of maintaining high processing accuracy of a workpiece when performing additional processing on the workpiece using a directed energy deposition method. The processing machine includes an additional processing head that supplies powder material to the workpiece and irradiates it with laser light, and a first holding unit and a second holding unit for rotatably holding the workpiece. The first holding unit and the second holding unit are arranged opposite each other in the direction of the workpiece's rotation axis and are configured to hold the workpiece from both sides.

[0003] When the workpiece is irradiated with laser light, the workpiece thermally expands (see paragraph

[0005] ). Therefore, the processing machine moves the first holding unit and the second holding unit relatively away from each other when performing additional processing on the workpiece. In this way, the processing machine prevents the surface of the workpiece from being distorted between the first holding unit and the second holding unit. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2023-125537 Summary of the Invention [Problem to be solved by the invention]

[0005] When the powder material is supplied to the end of the workpiece, some of the powder material may fall off the end of the workpiece, resulting in a workpiece that is smaller than intended.

[0006] In view of the above, there is a demand for a technique for improving the accuracy of additional machining of a workpiece compared to the conventional technique. [Means for solving the problem]

[0007] In one example of the present disclosure, an additive machining apparatus includes a laser head capable of performing additive machining on a workpiece by supplying powder material to the workpiece and irradiating the workpiece with laser light, a drive unit for driving the laser head, and a control unit for controlling the additive machining apparatus. The control unit drives the laser head to perform additive machining of an additional portion of a desired shape on the workpiece. The additive machining process includes driving the laser head so that, when additionally machining a horizontal end of the additional portion, an optical axis of the laser head is directed from the outside of the additional portion toward the end in a top view.

[0008] In one example embodiment of the present disclosure, the additional machining device further includes a work spindle for holding one side of the workpiece and rotating the workpiece about a predetermined axis, and a tailstock mechanism for tailstocking the other side of the workpiece. In the additional machining process, the control unit performs the workpiece rotation process by the work spindle and the laser head drive process in parallel.

[0009] In one example of the present disclosure, the tailstock mechanism includes a center pin configured to be able to move back and forth in the direction of the specified axis, and an elastic member that generates an elastic force to press the center pin toward the workpiece.

[0010] In one example of the present disclosure, the additional processing process includes driving the laser head so that the angle formed between the optical axis and a plane perpendicular to the specified axis becomes larger as the additional processing position moves toward the very end of the additional portion in the direction of the specified axis.

[0011] In one example of the present disclosure, the additional processing process includes a process of driving the laser head while maintaining the optical axis parallel to the direction of gravity during additional processing other than the end portion.

[0012] In one example of the present disclosure, the additional processing process includes maintaining a constant distance from the laser head to the additional portion in the direction of the optical axis when additional processing is performed at the end and when additional processing is performed at a portion other than the end.

[0013] Another example of the present disclosure provides an additive processing method using an additive processing apparatus. The additive processing apparatus includes a laser head capable of performing additive processing on a workpiece by supplying powder material to the workpiece and irradiating the workpiece with laser light, and a drive unit for driving the laser head. The additive processing method includes a step of additionally processing an additional portion of a desired shape on the workpiece by driving the laser head. The additional processing step includes a step of driving the laser head so that, when additionally processing a horizontal end of the additional portion, an optical axis of the laser head faces from the outside of the additional portion toward the end in a top view.

[0014] In another example of the present disclosure, an additive processing program for an additive processing apparatus is provided. The additive processing apparatus includes a laser head capable of performing additive processing on the workpiece by supplying powder material to the workpiece and irradiating the workpiece with laser light, and a drive unit for driving the laser head. The additive processing program causes the additive processing apparatus to execute a process of additively processing an additional portion of a desired shape on the workpiece by driving the laser head. The additive processing process includes a process of driving the laser head so that, when additionally processing a horizontal end of the additional portion, an optical axis of the laser head is directed from the outside of the additional portion toward the end in a top view.

[0015] 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 explanation of the drawings]

[0016] [Figure 1] FIG. 2 is a diagram showing an example of the appearance of an additional processing device. [Figure 2] FIG. 2 is a diagram illustrating an example of a device configuration of an additional processing device. [Figure 3] FIG. 10 is a diagram showing additional processing of a workpiece by a laser head. [Figure 4] FIG. 10 is a diagram for explaining lamination processing of a workpiece. [Figure 5] FIG. 10 is a diagram illustrating an outline of a driving path expansion process. [Figure 6] 6A and 6B are diagrams illustrating a process of expanding the drive path shown in FIG. 5. [Figure 7] FIG. 2 is a diagram illustrating an example of a drive mechanism of an additional processing device. [Figure 8] FIG. 2 illustrates an example of a hardware configuration of a control unit. [Figure 9] 10 is a flowchart showing the flow of additional processing. [Figure 10] FIG. 10 is a diagram showing an additional processing step for a certain layer. [Figure 11] FIG. 11 is a diagram showing an additional processing step following FIG. 10. [Figure 12] FIG. 12 is a diagram showing an additional processing step following FIG. [Figure 13] 10A and 10B are diagrams illustrating the manner in which the edges are additionally processed in different layers. [Figure 14] 10 is a flowchart showing a flow of additional processing according to a second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0017] 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 description thereof will not be repeated. Note that each embodiment and each modified example described below may be selectively combined as appropriate.

[0018] [First embodiment] <Appearance of the additive processing apparatus 100> First, referring to FIG. 1, the additive processing apparatus 100 according to the embodiment will be described. FIG. 1 is a diagram showing an example of the appearance of the additive processing apparatus 100.

[0019] The additive processing apparatus 100 is a processing machine capable of performing additive processing (AM (Additive manufacturing) processing) on a workpiece. The additive processing apparatus 100 performs additive processing by supplying a powder material to the workpiece and irradiating the workpiece with a laser beam.

[0020] Note that the additive processing apparatus 100 may be a processing machine capable of not only additive processing of a workpiece but also subtractive processing (SM (Subtractive manufacturing)) of the workpiece. Examples of the subtractive processing function include a milling function and a turning function.

[0021] The additive 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 additive processing apparatus 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 opened and closed by a drive source such as a motor, or may be configured to be opened and closed manually.

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

[0024] <Device configuration of the additive processing apparatus 100> Next, the device configuration of the additional processing device 100 will be described with reference to Fig. 2. Fig. 2 is a diagram showing an example of the device configuration of the additional processing device 100. Fig. 2 shows, as an example of the additional processing device 100, an AM / SM hybrid processing machine that is capable of additional processing of a workpiece and subtractive processing of a workpiece.

[0025] As described above, the additional processing device 100 is provided with the cover body 130. The cover body 130 forms the exterior of the additional processing device 100, and also defines a processing area AR in which additional processing of the workpiece W is performed.

[0026] The additional machining device 100 also includes a bed 11 , a tool rest 16 , a workpiece spindle 22 , a tailstock mechanism 25 , a tool spindle 30 , and a laser head 140 .

[0027] For ease of explanation, the direction of the rotation axis of the workpiece spindle 22 will also be referred to as the "Z-axis direction." The Z-axis direction is parallel to the rotation axes AX1 and AX2 shown in FIG. 2. A direction on a horizontal plane perpendicular to the Z-axis direction will also be referred to as the "X-axis direction." A direction perpendicular to both the X-axis and Z-axis directions will be 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 within the additive machining apparatus 100. In the example of Fig. 2, the bed 11 supports the tool rest 16, the workpiece spindle 22, the tailstock mechanism 25, the tool spindle 30, 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 a rotation axis AX1. The turret 18 holds a plurality of tools spaced apart in the circumferential direction around the rotation axis AX1. The tool rest 16 is also configured to be movable in the X-axis and Y-axis directions by various drive mechanisms such as motors. 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 one side of the workpiece W. More specifically, the workpiece spindle 22 is provided with a chuck mechanism 23. The chuck mechanism 23 is a mechanism for fixing the workpiece W to the workpiece spindle 22. The workpiece spindle 22 is also configured to be rotatable about a rotation axis AX2 that extends along its axial direction.

[0031] The tailstock mechanism 25 is configured to support the workpiece W from the side opposite the workpiece spindle 22 so as not to impede the rotation of the workpiece W by the workpiece spindle 22. The tailstock mechanism 25 is also configured to be movable in the direction of the rotation axis AX2 by various drive mechanisms such as a motor. As a result, the tailstock mechanism 25 tailstocks the long workpiece W from the side opposite the workpiece spindle 22.

[0032] The configuration for realizing the tailstock is not particularly limited. As an example, the tailstock mechanism 25 includes a center pin 26 and an elastic member 27.

[0033] The center pin 26 is configured to be able to advance and retreat in the direction of the rotation axis AX2 (predetermined axis). As an example, the center pin 26 has a pin shape that extends in the direction of the rotation axis AX2. As a result, the center pin 26 tail-loads the end face of the workpiece W from the side opposite to the workpiece spindle 22.

[0034] The elastic member 27 is built into the tailstock mechanism 25 and is a member that presses the center pin 26 toward the workpiece W. In other words, the elastic member 27 generates an elastic force that presses the center pin 26 toward the workpiece W. This allows the tailstock mechanism 25 to stably support the workpiece W while absorbing thermal expansion of the workpiece W that occurs when additional processing is performed on the workpiece W. As an example, the elastic member 27 is a coil spring that extends around the rotation axis AX2.

[0035] The tool spindle 30 is provided, for example, at a position higher than the workpiece spindle 22 and the tailstock mechanism 25. The tool spindle 30 is configured to allow tools and a laser head 140 to be detachably attached. Fig. 2 shows an example in which the laser head 140 is attached to the tool spindle 30.

[0036] The laser head 140 can be attached to and detached from the tool spindle 30 by, for example, an automatic tool changer (ATC). The additional machining device 100 attaches the laser head 140 to the tool spindle 30 when performing additional machining of the workpiece W. On the other hand, the additional machining device 100 attaches a tool to the tool spindle 30 when performing subtractive machining of the workpiece W.

[0037] An example of the removal process is milling, in which a rotating tool is brought into contact with the workpiece W fixed to the workpiece spindle 22. Another example of the removal process is turning, in which a tool is pressed against the workpiece W rotating about the rotation axis AX2.

[0038] The laser head 140 performs additional machining by a DED (Direct Energy Deposition) method while attached to the tool spindle 30. The laser head 140 has a head main body 142 and a laser nozzle 146 as a mechanism for realizing the additional machining.

[0039] 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 upon irradiation with laser light.

[0040] The laser nozzle 146 irradiates the workpiece W with laser light and defines the irradiation region of the laser light on the workpiece W. The powder material supplied to the laser head 140 is discharged toward the workpiece W through the laser nozzle 146.

[0041] <C. Additional Processing> Next, referring to FIGS. 3 and 4, the additional processing by the laser head 140 will be described in more detail. FIG. 3 is a view showing the state of additional processing of the workpiece W by the laser head 140 from the Z-axis direction.

[0042] The additional processing apparatus 100 is configured, for example, to enable high-speed additional processing. As an example, as high-speed additional processing technology, EHLA (Extreme High-speed Laser Application) can be mentioned.

[0043] More specifically, while the laser head 140 moves in the direction of the rotation axis AX2 of the workpiece spindle 22 (i.e., the Z-axis direction), the laser head 140 irradiates the workpiece W that is rotationally driven by the workpiece spindle 22 with the laser light LS. As a result, the irradiated portion of the laser light LS melts, and a molten pool MP is formed on the workpiece W.

[0044] Also, the laser head 140 supplies the powder material PM to the workpiece W in parallel with the irradiation of the laser light LS. Since the focal point F of the laser light LS is located above the surface of the workpiece W, the supplied powder material PM melts before reaching the surface of the workpiece W by the laser light LS. As a result, the molten powder material PM is introduced into the molten pool MP. When the molten pool MP hardens on the workpiece W, it becomes a layer SL.

[0045] Layers SL are repeatedly formed on the workpiece W to achieve layering processing. Fig. 4 is a diagram for explaining layering processing on the workpiece W. Fig. 4 shows a cross-sectional view of the workpiece W along the XY plane.

[0046] 4, a flange-shaped additional portion PB is formed on a base material portion PA of a workpiece W. The additional portion PB is formed by stacking a plurality of layers SL1 to SL4 in order.

[0047] More specifically, the additional processing device 100 first drives the laser head 140 to the start position of additional processing on the first layer SL1. Thereafter, the additional processing device 100 performs the following processes in parallel: rotating the workpiece W using the workpiece spindle 22, driving the laser head 140 toward the positive side in the Z-axis direction, emitting the laser beam LS using the laser head 140, and supplying the powder material PM. When the laser head 140 has reached the end position of the additional processing on the layer SL1, the additional processing device 100 stops emitting the laser beam LS using the laser head 140 and supplying the powder material PM. As a result, the layer SL1 is formed on the workpiece W.

[0048] Thereafter, the additional processing device 100 drives the laser head 140 to the start position of additional processing on the second layer SL2. Next, the additional processing device 100 performs the following processes in parallel: rotating the workpiece W using the workpiece spindle 22, driving the laser head 140 toward the positive side in the Z-axis direction, irradiating the laser beam LS by the laser head 140, and supplying the powder material PM. When the laser head 140 has reached the end position of the additional processing on the layer SL2, the additional processing device 100 stops irradiating the laser beam LS by the laser head 140 and supplying the powder material PM. As a result, the layer SL2 is formed on the workpiece W.

[0049] By repeating the above-described process, the additional processing device 100 can additionally process the base material portion PA of the workpiece W to form additional portions PB of various shapes.

[0050] Note that the formation of the additional portion PB does not necessarily have to be achieved by high-speed additive processing. As an example, the additive processing apparatus 100 may form the additional portion PB by additive processing that rotates the work spindle 22 at a low speed. In this case, the additive processing apparatus 100 forms the additional portion PB with the focus F of the laser beam LS positioned on the surface of the work W.

[0051] <D. Expansion Function of Drive Path>

[0052] (D1. Overview) Next, an overview of the process of expanding the drive path of the laser head 140 will be described.

[0053] The additive processing apparatus 100 generates a drive path of the laser head 140 based on three-dimensional data that defines the shape of the additional portion PB of the work W. Then, the additive processing apparatus 100 drives the laser head 140 according to the generated drive path to form the additional portion PB on the work W.

[0054] At this time, the work W thermally expands due to the irradiation of the laser beam during additive processing and contracts after the completion of additive processing. Therefore, the additional portion PB of the work W may become smaller than the intended size.

[0055] Therefore, the additive processing apparatus 100 according to the present embodiment expands the drive path generated from the three-dimensional data in the horizontal direction of the additional portion PB. As a result, the additive processing apparatus 100 forms an additional portion PB having a size larger than the additional portion PB defined in the three-dimensional data on the work W. The additional portion PB contracts because it reaches room temperature after the additive processing of the work W. As a result, the additional portion PB becomes the intended size. As a result, the additive processing accuracy of the work is improved compared to the conventional case.

[0056] (D2. Specific Example) Next, a specific example of the process of expanding the drive path of the laser head 140 will be described with reference to FIGS. 5 and 6. FIG. 5 is a diagram schematically showing the expansion process of the drive path.

[0057] As shown in step S1, the additive processing device 100 first acquires three-dimensional data 124 including the additional portion PB of the workpiece W. The three-dimensional data 124 is, for example, data designed using CAD (Computer Aided Design). The three-dimensional data 124 includes at least data indicating the shape of the additional portion PB. Note that the three-dimensional data 124 may also include the shape of the base material portion PA that forms the additional portion PB.

[0058] In step S2, the additive processing device 100 generates a drive path R for the laser head 140 based on the three-dimensional data 124. The drive path R is a command value that defines the path of the laser head 140 when forming the additional portion PB on the workpiece W.

[0059] The drive path R is generated by any method. As one example, the drive path R may be designed by a designer. As another example, the drive path R may be automatically generated by CAM (Computer Aided Manufacturing). CAM is a tool for automatically generating an NC (Numerically Control) program required for processing by the additive processing device 100 based on three-dimensional data 124 created by CAD.

[0060] The NC program generated by the CAM includes a drive path R of the laser head 140. In addition, the NC program may include the attitude (for example, angle, etc.) of the laser head 140 during additional processing, the speed of the laser head 140 during additional processing, a command to irradiate the laser head 140 with laser light (for example, ON / OFF command) during additional processing, and a command to supply the powder material PM of the laser head 140 during additional processing (for example, ON / OFF command).

[0061] The NC program generated by the CAM may include not only command values ​​related to the laser head 140 but also command values ​​related to the workpiece spindle 22. As an example, the NC program may include the rotational speed of the workpiece spindle 22 during additional machining.

[0062] The driving path R is generated for each layer to be formed. In the example of step S2 in Fig. 5, driving paths R1 to RN for forming the first to Nth layers (N is a natural number of 2 or more), respectively, are shown.

[0063] Driving path R1 includes a start position SP1 of the laser head 140 during additional processing of the first layer and an end position EP1 of the laser head 140 during additional processing of the first layer. Driving path R2 includes a start position SP2 of the laser head 140 during additional processing of the second layer and an end position EP2 of the laser head 140 during additional processing of the second layer. Driving path RN includes a start position SPN of the laser head 140 during additional processing of the Nth layer and an end position EPN of the laser head 140 during additional processing of the Nth layer.

[0064] In step S3, the additional processing device 100 expands the drive path R generated from the three-dimensional data 124 in the direction of the rotation axis AX2 (that is, the Z-axis direction) to generate an expanded drive path R'.

[0065] 5, the additional processing device 100 extends the drive paths R1 to RN, respectively, to generate drive paths R1' to RN'. At this time, the additional processing device 100 may extend the drive paths R1 to RN on one side of the rotation axis AX2, or may extend the drive paths R1 to RN on both sides of the rotation axis AX2.

[0066] As an example, the additional processing device 100 moves the start positions SP1 to SPN of the drive paths R1 to RN to the negative side in the Z-axis direction. As a result, the start positions SP1 to SPN are updated to start positions SP1' to SPN'. As a result, drive paths R1' to RN' extended to the negative side in the Z-axis direction are generated.

[0067] As another example, the additional processing device 100 moves the end positions EP1 to EPN of the drive paths R1 to RN to the positive side in the Z-axis direction. As a result, the end positions EP1 to EPN are updated to end positions EP1' to EPN'. As a result, drive paths R1' to RN' extended to the positive side in the Z-axis direction are generated.

[0068] As yet another example, the additional processing device 100 moves the start positions SP1-SPN of the drive paths R1-RN to the negative side in the Z-axis direction, and moves the end positions EP1-EPN of the drive paths R1-RN to the positive side in the Z-axis direction. As a result, the start positions SP1-SPN are updated to start positions SP1'-SPN', and the end positions EP1-EPN are updated to end positions EP1'-EPN'. As a result, drive paths R1'-RN' extended on both sides in the Z-axis direction are generated.

[0069] The additional processing device 100 then drives the laser head 140 according to the expanded drive path R' to form the additional portion PB on the workpiece W. At this time, as described with reference to FIG. 2, the additional processing device 100 performs additional processing while holding the workpiece W between the workpiece spindle 22 and the tailstock mechanism 25. Because the tailstock mechanism 25 has an elastic member 27 for absorbing thermal expansion, the size of the workpiece W changes in the direction of the rotation axis AX2 during additional processing. In response to this change, the additional processing device 100 expands the drive path R generated from the three-dimensional data 124 in the direction of the rotation axis AX2. Therefore, even if the workpiece W shrinks after the additional processing is completed due to its temperature reaching room temperature, the additional portion PB will have the intended size in the direction of the rotation axis AX2. As a result, the processing accuracy of the additional portion PB in the direction of the rotation axis AX2 is improved.

[0070] The size of the workpiece W is more likely to change on the installation side of the tailstock mechanism 25, which has an elastic function, than on the installation side of the workpiece spindle 22. Therefore, the additional processing device 100 preferably expands the drive path R generated from the three-dimensional data 124 at least on the installation side of the tailstock mechanism 25.

[0071] The expansion method will be described below with reference to Fig. 6. Fig. 6 is a diagram schematically illustrating the process of expanding the driving path R shown in Fig. 5 to a driving path R'.

[0072] Although Figure 6 shows an example in which one drive path R is extended, typically, the additional processing device 100 applies the extension process shown in Figure 6 to each of the drive paths R1 to RN shown in Figure 5.

[0073] In this example, the additional processing device 100 expands the drive path R by an expansion distance ΔE1 on the installation side of the workpiece spindle 22, and expands the drive path R by an expansion distance ΔE2 on the installation side of the tailstock mechanism 25. At this time, the additional processing device 100 makes the expansion distance ΔE2 on the installation side of the tailstock mechanism 25 longer than the expansion distance ΔE1 on the installation side of the workpiece spindle 22. This allows the additional processing device 100 to further improve the additional processing accuracy of the workpiece W.

[0074] The expansion distance ΔE1 on the installation side of the workpiece spindle 22 may be 0. That is, the additional processing device 100 may expand the drive path R only on the installation side of the tailstock mechanism 25.

[0075] Furthermore, the additional part PB is more likely to be thermally displaced in the direction of the rotation axis AX2 the closer it is to the tailstock mechanism 25. Therefore, the additional processing device 100 may change the expansion distances ΔE1, ΔE2 depending on the position of the additional part PB relative to the workpiece W. In this case, the additional processing device 100 increases the expansion distances ΔE1, ΔE2 the closer the position of the additional part PB is to the tailstock mechanism 25. This allows the additional processing device 100 to further improve the additional processing accuracy of the workpiece W.

[0076] The extension distance of the drive path R can be determined by various factors other than those described above. As an example, the additional processing device 100 increases the extension distances ΔE1 and ΔE2 as the width of the workpiece W in the direction of the rotation axis AX2 increases. In other words, the additional processing device 100 decreases the extension distances ΔE1 and ΔE2 as the width of the workpiece W in the direction of the rotation axis AX2 decreases.

[0077] As another example, the additive processing apparatus 100 increases the expansion distances ΔE1 and ΔE2 as the temperature of the workpiece W during additive processing is higher. In other words, the additive processing apparatus 100 decreases the expansion distances ΔE1 and ΔE2 as the temperature of the workpiece W during additive processing is lower. The temperature of the workpiece W during additive processing may be measured by a temperature sensor or may be estimated based on the irradiation intensity of the laser light irradiated from the laser head 140.

[0078] <E. Driving Mechanism of Additive Processing Apparatus 100> Next, referring to FIG. 7, the driving mechanism in the additive processing apparatus 100 will be described. FIG. 7 is a diagram showing an example of the driving mechanism of the additive processing apparatus 100.

[0079] As shown in FIG. 7, the additive processing apparatus 100 includes a control unit 50 and driving units 210, 220, 230A, 230B, and 240.

[0080] The control unit 50 controls various devices in the additive 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).

[0081] The driving unit 210 is a driving mechanism for rotationally driving the workpiece spindle 22. The driving unit 210 may be composed of a single driving unit or may be composed of a plurality of driving units. In the example of FIG. 7, the driving unit 210 is composed of a motor driver 211C and a motor 212C.

[0082] The motor driver 211C sequentially receives input of the target rotation angle or target rotation speed of the work spindle 22 from the control unit 50, and outputs a current corresponding to the target rotation angle or target rotation speed to the motor 212C. This causes the work held by the work spindle 22 to rotate around 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.

[0083] The drive unit 220 is a drive mechanism for driving the tailstock mechanism 25. The drive unit 220 may be composed of a single drive unit or multiple drive units. In the example of Fig. 7, the drive unit 220 is composed of a motor driver 221Z and a motor 222Z.

[0084] The motor driver 221Z sequentially receives input of target positions for the workpiece 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 mechanism 25 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.

[0085] 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 configured with a single driving unit or may be configured with multiple driving units. In the example of Fig. 7, the driving unit 230A is configured with motor drivers 231X to 231Z and motors 232X to 232Z.

[0086] 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 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.

[0087] 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. In this way, the motor 232Y drives the tool spindle 30 to any 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.

[0088] 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. This causes the motor 232Z to move the tool spindle 30 to any 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.

[0089] The drive unit 230B is a drive mechanism for rotationally driving the tool spindle 30. The drive unit 230B may be configured with a single drive unit or multiple drive units. In the example of Fig. 7, the drive unit 230B is configured with motor drivers 231A and 231B and motors 232A and 232B.

[0090] The motor driver 231A sequentially receives input of a target rotation angle or a target rotation speed of the tool spindle 30 about 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 232A. The motor 232A drives the tool spindle 30 to rotate about the X-axis direction. The motor 232A may be an AC motor, a stepping motor, a servo motor, or any other type of motor.

[0091] The motor driver 231B sequentially receives input of a target rotation angle or a target rotation speed of the tool spindle 30 around 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 the tool spindle 30 to rotate around 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 any other type of motor.

[0092] The drive unit 240 is a drive mechanism for driving the tool post 16 and the turret 18. The drive unit 240 may be composed of a single drive unit or multiple drive units. In the example of Fig. 7, the drive unit 240 is composed of motor drivers 241C, 241Y, and 241Z and motors 242C, 242Y, and 242Z.

[0093] 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 corresponding 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.

[0094] 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.

[0095] 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.

[0096] <F. Hardware Configuration of Control Unit 50> Next, referring to FIG. 8, the hardware configuration of the control unit 50 shown in FIG. 7 will be described. FIG. 8 is a diagram showing an example of the hardware configuration of the control unit 50.

[0097] As described above, the control unit 50 may be a CNC or a PLC. FIG. 8 shows the hardware configuration of the control unit 50 as a CNC.

[0098] 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.

[0099] 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.

[0100] 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. Upon 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.

[0101] The communication interface 104 is an interface for realizing communication with various devices. The additional processing device 100 communicates with, for example, various drive units (such as the above-mentioned drive units 210, 220, 230A, 230B, and 240) for realizing additional processing of the workpiece via the communication interface 104.

[0102] 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, the above-mentioned three-dimensional data 124, etc. The storage location of the machining program 122 and the three-dimensional data 124 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), etc.

[0103] Further, the machining program 122 may be provided not as a single program but incorporated into a part of any 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. Furthermore, a part or all of the functions provided by the machining program 122 may be realized by dedicated hardware. Furthermore, 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.

[0104] <G. Control Flow of Additional Machining> Next, referring to FIG. 9, the control flow of additional machining will be described. FIG. 9 is a flowchart showing the flow of additional machining processing.

[0105] The processing shown in FIG. 9 is realized, for example, when the control unit 50 of the additional machining apparatus 100 executes the above-described machining program 122. In other aspects, part or all of the processing may be executed by circuit elements or other hardware.

[0106] In step S110, the control unit 50 acquires three-dimensional data 124 including the additional part PB of the workpiece W.

[0107] In step S112, the control unit 50 generates an NC program that defines a drive command for the laser head 140 based on the three-dimensional data 124 acquired in step S110. The NC program includes a drive path of the laser head 140 for forming the additional part PB. The NC program may also include the posture (such as angle) of the laser head 140 during additional machining, the speed of the laser head 140, an irradiation command for the laser light from the laser head 140, a supply command for the powder material PM from the laser head 140, and the like. Furthermore, the NC program may include command values such as the rotational speed of the workpiece spindle 22.

[0108] In step S114, the control unit 50 extends the drive path of the laser head 140 defined in the NC program generated in step S112. Since the extension process of the drive path is as described above, the description thereof will not be repeated.

[0109] In step S116, the control unit 50 controls the laser head 140 according to the NC program after the extension process in step S114. Thereby, the additional processing device 100 forms an additional portion PB on the workpiece W.

[0110] In the above description, an example in which the processes of steps S110, S112, S114, and S116 are continuously executed has been described. However, these processes do not necessarily have to be continuously executed. As an example, the generation process of the NC program shown in steps S110, S112, and S114 and the additional processing process shown in step S116 may be executed at different timings. In this case, these processes may be executed by the same device or by different devices.

[0111] [Second Embodiment] <H. Overview> Next, the additional processing device 100 according to the second embodiment will be described.

[0112] The additional processing device 100 according to the first embodiment described above extended the drive path of the laser head 140 in consideration of the thermal expansion of the workpiece during additional processing. Thereby, the additional processing device 100 improved the additional processing accuracy of the workpiece.

[0113] On the other hand, the additional processing device 100 according to the second embodiment improves the additional processing accuracy of the workpiece in different processing modes. Specifically, when the powder material PM is supplied to the end of the additional portion PB, a part of the powder material PM may fall from the end of the additional portion PB. As a result, the width of the additional portion PB may become shorter than intended. This becomes more prominent as the number of stacked layers increases.

[0114] Therefore, when the additional processing device 100 according to the second embodiment performs additional processing on the horizontal end portion of the additional portion PB, the laser head 140 is driven so that the optical axis of the laser head 140 faces the end portion from the outside of the additional portion PB in a top view. Here, the optical axis refers to a straight line connecting the center of the laser light emission port in the laser head 140 and the focal point F (see FIG. 3) of the laser light LS. By driving the laser head 140 so that the optical axis is inclined with respect to the gravitational direction, the powder material PM is more likely to enter the inside of the workpiece W. As a result, the fall of the powder material PM from the end portion of the workpiece W is suppressed, and the additional processing accuracy is improved.

[0115] In the following, the differences between the additional processing device 100 according to the first embodiment and the additional processing device 100 according to the second embodiment will be described, and the description of their common points will be omitted.

[0116] <I. Driving mode of the laser head 140> Next, referring to FIGS. 10 to 12, the driving mode of the laser head 140 during the additional processing according to the present embodiment will be described.

[0117] FIG. 10 is a diagram showing the additional processing step S10 of the layer SL4. FIG. 11 is a diagram showing the additional processing step S11 of the layer SL4 following FIG. 10. FIG. 12 is a diagram showing the additional processing step S12 of the layer SL4 following FIG. 11.

[0118] In the following, the angle formed by the optical axis AXL of the laser head 140 and the orthogonal plane SF of the rotation axis AX2 is defined as the inclination angle θ of the laser head 140.

[0119] Also, the end portion of the additional portion PB in the direction of the rotation axis AX2 is defined as the end portion E. The end portion E is, for example, a portion of the additional portion PB included at a predetermined distance from the end face of the additional portion PB in the direction of the rotation axis AX2. Also, one side of the end portion E in the direction of the rotation axis AX2 is referred to as the end portion E1, and the other side of the end portion E in the direction of the rotation axis AX2 is referred to as the end portion E2.

[0120] Assume that additional processing of layer SL4 has started in the additional processing step S10. Based on this, the additional processing device 100 drives the laser head 140 so that the tilt angle θ is greater than 0°. At this time, the additional processing device 100 tilts the laser head 140 so that the optical axis AXL points from the outside of the additional portion PB toward the end E1 in a top view. The tilt angle θ in the additional processing step S10 is, for example, greater than or equal to 10° and less than or equal to 45°.

[0121] In the additional processing step S11, it is assumed that the additional processing position has passed the end E1. During additional processing at a position other than the end E1, the additional processing device 100 drives the laser head 140 while maintaining the optical axis AXL parallel to the direction of gravity. At this time, the optical axis AXL becomes parallel to the orthogonal plane SF, and the tilt angle θ becomes 0°. As a result, the powder material PM is supplied in the direction of gravity (i.e., the positive side in the Y-axis direction). Thereafter, the additional processing device 100 drives the laser head 140 toward the positive side in the Z-axis direction while maintaining the tilt angle θ at 0°.

[0122] In the additional processing step S12, it is assumed that the additional processing position has reached the end E2. Based on this, the additional processing device 100 drives the laser head 140 so that the tilt angle θ is greater than 0°. At this time, the additional processing device 100 tilts the laser head 140 so that the optical axis AXL faces from the outside of the additional portion PB toward the end E2 in a top view. That is, in the additional processing step S12, the additional processing device 100 tilts the laser head 140 in the opposite direction to that in the additional processing step S10. The tilt angle θ of the laser head 140 in the additional processing step S12 is, for example, greater than or equal to 10° and less than or equal to 45°.

[0123] Preferably, the additional processing device 100 maintains a constant distance from the laser head 140 to the additional portion PB throughout the additional processing steps S10 to S12. As an example, the distance is the distance in the direction of the optical axis AXL. In this case, the additional processing device 100 maintains a constant distance from the laser head 140 to the additional portion PB in the direction of the optical axis AXL throughout the additional processing steps S10 to S12. This makes it difficult for the focal position of the laser light with respect to the additional portion PB to fluctuate, stabilizing the quality of the additional processing.

[0124] As another example, the separation distance is the distance in the direction of gravity. In this case, the additional processing device 100 performs the additional processing in the additional processing steps S10 to S12 while maintaining the position of the laser head 140 in the direction of gravity.

[0125] Note that the additional processing device 100 may change the tilt angle θ in stages during additional processing of the end portion E, or may maintain the tilt angle θ constant. Preferably, the additional processing device 100 increases the tilt angle θ as the additional processing position moves toward the extreme end of the additional portion PB in the direction of the rotation axis AX2. In other words, the additional processing device 100 decreases the tilt angle θ as the additional processing position moves toward the inside of the additional portion PB in the direction of the rotation axis AX2. This allows the additional processing device 100 to reduce the amount of powder material PM falling from the end portion E and to more stabilize the quality of the additional processing.

[0126] Furthermore, although the additional processing steps S10 to S12 for the layer SL4 have been described above, the additional processing apparatus 100 may set the inclination angle θ to be greater than 0° during additional processing of the end portions E of the layers SL1 to SL4. In this case, the inclination angle θ at the end portions E of the layers SL1 to SL4 may be constant or may be changed for each layer. Preferably, the additional processing apparatus 100 drives the laser head 140 so that the inclination angle θ at the end portions E of the upper layers is greater than the inclination angle θ at the end portions E of the lower layers.

[0127] FIG. 13 is a diagram showing the mode of additional processing of the end portion E2 in different layers SL3 and SL4. In FIG. 13(A), the inclination angle θ of the laser head 140 during the additional processing of the end portion E2 of the layer SL3 is shown as "θ1". In FIG. 13(B), the inclination angle θ of the laser head 140 during the additional processing of the end portion E2 of the layer SL4 is shown as "θ2".

[0128] As shown in FIG. 13, the additive manufacturing apparatus 100 makes the inclination angle θ2 during the additive manufacturing of the layer SL4 larger than the inclination angle θ1 during the additive manufacturing of the lower layer SL3. As a result, the powder material PM is supplied more obliquely from the side toward the end portion E in the upper layer. As a result, the additive manufacturing apparatus 100 can reliably stack the powder material PM layer by layer, and can improve the additive manufacturing accuracy.

[0129] <J. Control Flow of Additive Manufacturing> Next, referring to FIG. 14, the control flow of additive manufacturing according to the second embodiment will be described. FIG. 14 is a flowchart showing the flow of the additive manufacturing process according to the present embodiment.

[0130] The process shown in FIG. 14 is realized, for example, when the control unit 50 of the additive manufacturing apparatus 100 executes the above-described processing program 122. In other aspects, part or all of the process may be executed by circuit elements or other hardware.

[0131] In step S210, the control unit 50 initializes the variable "N". At this time, the variable "N" is initialized to "1".

[0132] In step S212, the control unit 50 acquires the drive path of the laser head 140 in the Nth layer, and moves the laser head 140 to the start position defined in the drive path.

[0133] In step S214, the control unit 50 drives the laser head 140 to assume an inclined posture that makes the above-mentioned inclination angle θ (see FIG. 10) greater than 0°. Thereafter, the control unit 50 starts the irradiation of laser light by the laser head 140 and the supply of powder material by the laser head 140, and drives the laser head 140 according to the drive path acquired in step S212.

[0134] In step S220, the control unit 50 determines whether the current additional processing position has passed through the end E1 (see FIG. 10). If the control unit 50 determines that the current additional processing position has passed through the end E1 (YES in step S220), the control unit 50 switches control to step S222. If not (NO in step S220), the control unit 50 executes the process of step S220 again.

[0135] In step S222, the control unit 50 drives the laser head 140 to assume an upright posture with the tilt angle θ (see FIG. 11) set to 0° during additional machining between the ends E1 and E2. Thereafter, the control unit 50 continues additional machining according to the drive path acquired in step S212.

[0136] In step S230, the control unit 50 determines whether the current additional processing position has reached the end E2 (see FIG. 12). If the control unit 50 determines that the current additional processing position has reached the end E2 (YES in step S230), the control unit 50 switches control to step S232. If not (NO in step S230), the control unit 50 executes the process of step S230 again.

[0137] In step S232, the control unit 50 drives the laser head 140 to assume an inclined posture that makes the above-mentioned inclination angle θ (see FIG. 12) greater than 0°, and continues additional machining according to the drive path acquired in step S212.

[0138] In step S240, the control unit 50 determines whether the current position of the laser head 140 has reached the end position defined in the drive path acquired in step S212. If it is determined that the current position of the laser head 140 has reached the end position (YES in step S240), the control is switched to step S242. Otherwise (NO in step S240), the control unit 50 executes the process of step S240 again.

[0139] In step S242, the control unit 50 stops the additional processing. That is, the control unit 50 stops the irradiation of the laser light LS by the laser head 140 and the supply of the powder material PM by the laser head 140.

[0140] In step S250, the control unit 50 determines whether a predetermined end condition is satisfied. As an example, the end condition is satisfied when the variable "N" is greater than or equal to a predetermined value. The predetermined value is a natural number of 1 or more. If the control unit 50 determines that the predetermined end condition is satisfied (YES in step S250), the process shown in FIG. 14 is terminated. Otherwise (NO in step S250), the control unit 50 switches the control to step S252.

[0141] In step S252, the control unit 50 increments the variable "N". That is, the control unit 50 adds "1" to the variable "N".

[0142] <K. Others> The above first and second embodiments may be selectively combined as appropriate. Also, the ideas of the above first and second embodiments can be variously improved and modified. Hereinafter, modifications of the above first and second embodiments will be described.

[0143] The above description has been given assuming an additive machining apparatus 100 that includes a workpiece spindle 22 and a tailstock mechanism 25. However, the technical concepts described in this specification can also be applied to an additive machining apparatus 100 that does not include a workpiece spindle 22 and a tailstock mechanism 25. The additive machining apparatus 100 forms an additive portion PB by sequentially forming layers on a non-rotating workpiece W. The technical concepts described in this specification can also be applied to such an additive machining apparatus 100.

[0144] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the above description, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0145] 11 bed, 16 tool rest, 18 turret, 22 workpiece spindle, 23 chuck mechanism, 25 tailstock mechanism, 26 center pin, 27 elastic member, 30 tool spindle, 50 control unit, 100 additional processing device, 101 control circuit, 102 ROM, 103 RAM, 104 communication interface, 109 internal bus, 120 auxiliary storage device, 122 processing program, 124 three-dimensional data, 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 processing area, AX1 rotation axis, AX2 rotation axis, AXL optical axis, DR door, E end, E1 end, E2 end, EPN end position, EP1 end position, EP1' end position, EP2 end position, F focus, LS laser beam, MP molten pool, PA base material part, PB additional part, PM powder material, R drive pass, R1 drive pass, R1' drive pass, R2 drive pass, RN drive pass, R' drive pass, SF orthogonal surface, SL layer, SL1 layer, SL2 Layer, SL3 layer, SL4 layer, SPN start position, SP1 start position, SP1' start position, SP2 start position, W work, ΔE1 expansion distance, ΔE2 expansion distance, θ tilt angle, θ1 tilt angle, θ2 tilt angle.

Claims

1. An additive processing device, a laser head capable of performing additional processing on a workpiece by supplying a powder material to the workpiece and irradiating the workpiece with laser light; a driving unit for driving the laser head; a control unit for controlling the additional processing device, the control unit drives the laser head to perform additional machining of an additional portion of a desired shape on the workpiece; The additional processing device includes a process of driving the laser head so that the optical axis of the laser head faces from the outside of the additional portion toward the end portion when additionally processing the horizontal end portion of the additional portion.

2. The additional processing device further includes: a work spindle for holding one side of the workpiece and rotating the workpiece around a predetermined axis; a tailstock mechanism for tailstocking the other side of the workpiece, The additional machining device according to claim 1 , wherein the control unit executes a process of rotating the workpiece by the workpiece spindle and a process of driving the laser head in parallel in the additional machining process.

3. The tailstock mechanism includes: a center pin configured to be movable forward and backward in the direction of the predetermined axis; The additional processing device according to claim 2 , further comprising: an elastic member that generates an elastic force for pressing the center pin toward the workpiece.

4. 4. The additional processing device according to claim 2 or 3, wherein the additional processing process includes a process of driving the laser head so that the angle formed between the optical axis and a plane perpendicular to the specified axis becomes larger as the additional processing position moves toward the end of the additional portion in the direction of the specified axis.

5. 4. The additional processing device according to claim 2, wherein the additional processing step includes driving the laser head while maintaining the optical axis parallel to the direction of gravity during additional processing other than the end portion.

6. The additional processing device according to any one of claims 1 to 3, wherein the additional processing process includes a process of maintaining a constant distance from the laser head to the additional portion in the direction of the optical axis when additional processing is performed at the end and when additional processing is performed at a portion other than the end.

7. An additional processing method using an additional processing device, The additional processing device is a laser head capable of performing additional processing on a workpiece by supplying a powder material to the workpiece and irradiating the workpiece with laser light; a drive unit for driving the laser head, The additive processing method includes a step of additively processing an additional portion having a desired shape on the workpiece by driving the laser head, The additional processing method includes a step of driving the laser head so that the optical axis of the laser head faces from outside the additional portion toward the end portion when additionally processing the horizontal end portion of the additional portion.

8. An additive processing program for an additive processing device, The additional processing device is a laser head capable of performing additional processing on a workpiece by supplying a powder material to the workpiece and irradiating the workpiece with laser light; a drive unit for driving the laser head, the additional processing program causes the additional processing device to execute a process of additionally processing an additional portion of a desired shape on the workpiece by driving the laser head; The additional processing program includes a process of driving the laser head so that the optical axis of the laser head faces from the outside of the additional portion toward the end portion when additionally processing the horizontal end portion of the additional portion.

Images