Laser processing machine control device

Abstract

A control device for a laser processing machine is provided, which can maintain the inclination direction of a nozzle relative to a processing program path even when the tool diameter correction amount is changed, thereby improving processing accuracy. The control device (1) for a laser processing machine comprises: a tool center path calculation unit (12) which calculates the tool center path based on an offset vector relative to the processing program path; a first inclination direction calculation unit (131) which calculates the inclination direction of a nozzle (2) relative to the processing program path; a tool posture calculation unit (14) which calculates the posture of the nozzle (2) based on the inclination direction of the nozzle (2) calculated by the first inclination direction calculation unit (131) and the inclination angle of the nozzle (2) from a direction perpendicular to a plane of a workpiece (W) to the inclination direction in a plane orthogonal to the processing program path; a drive axis movement amount calculation unit (15) which calculates the movement amount of a drive axis based on the tool center path and the posture of the nozzle (2); and a drive axis control unit (16) which controls the drive axis based on the movement amount of the drive axis.

Description

Technical Field

[0001] The present disclosure relates to a control device for a laser processing machine. Background Art

[0002] Conventionally, in groove processing by a laser processing machine, the nozzle tilt direction relative to the nozzle travel direction is controlled. The nozzle tilt direction is set to a direction tilted by 90 degrees relative to the nozzle travel direction, for example, and in this case, so-called normal direction control is performed.

[0003] In the groove processing by the laser processing machine, the nozzle tilt angle is controlled from the direction perpendicular to the plane of the workpiece to the above-mentioned tilt direction in a plane orthogonal to the traveling direction of the nozzle. The nozzle tilt angle is controlled according to the processing shape, for example.

[0004] For example, Patent Document 1 has been proposed as a technique for performing groove processing using an NC laser cutting machine in order to cut out a component having a groove. Patent Document 1 describes changing the tilt angle of a laser head (nozzle) when processing the groove of a curved portion.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2007-275974 Summary of the invention

[0008] Problems to be solved by the invention

[0009] However, the nozzle tilt angle is sometimes changed in accordance with the processing shape and the like according to the program instruction. If the nozzle tilt angle is changed, the irradiation area of ​​the laser on the workpiece to be processed changes. Therefore, the irradiation distance of the laser is adjusted by the tool diameter correction function generally provided in the control device of the laser processing machine. That is, if the tool diameter correction is performed, the tool center path through which the center of the nozzle passes becomes a path different from the processing program path.

[0010] However, the nozzle tilt direction is automatically controlled to be constant as the tilt direction relative to the tool center path. When the tool diameter correction amount is changed, the direction of the tool center path changes, and the nozzle tilt direction changes accordingly. Therefore, there is a problem that the nozzle tilt direction relative to the machining program path changes, and the machining accuracy decreases.

[0011] Therefore, a control device for a laser processing machine that can maintain the tilt direction of the nozzle with respect to the processing program path even when the tool diameter correction amount is changed and can improve the processing accuracy is desired.

[0012] Means for solving problems

[0013] One method disclosed herein is a control device for a laser processing machine having a nozzle, comprising: a tool center path calculation unit, which generates an offset vector relative to a processing program path based on an analysis result of a processing program, and calculates a tool center path through which the center of the nozzle passes based on the offset vector; a first tilt direction calculation unit, which calculates the tilt direction of the nozzle relative to the processing program path based on the analysis result of the processing program; a tool posture calculation unit, which calculates the posture of the nozzle based on the tilt direction of the nozzle calculated by the first tilt direction calculation unit and the tilt angle of the nozzle from a direction perpendicular to the plane of the workpiece to the tilt direction in a plane orthogonal to the processing program path; a drive axis movement amount calculation unit, which calculates the movement amount of the drive axis based on the tool center path calculated by the tool center path calculation unit and the posture of the nozzle calculated by the tool posture calculation unit; and a drive axis control unit, which controls the drive axis based on the movement amount of the drive axis calculated by the drive axis movement amount calculation unit.

[0014] Effects of the Invention

[0015] According to the present disclosure, it is possible to provide a control device for a laser processing machine that can maintain the tilt direction of a nozzle with respect to a processing program path even when the tool diameter correction amount is changed, thereby improving processing accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a functional block diagram showing the configuration of a control device for a laser processing machine according to an embodiment of the present disclosure.

[0017] Figure 2 This is a diagram for explaining groove processing and is a perspective view of a groove processed product.

[0018] Figure 3 This is a diagram for explaining groove processing, and is a perspective view showing the posture and trajectory of the nozzle during groove processing.

[0019] Figure 4 This is a diagram for explaining groove processing, and is a plan view showing the trajectory of the nozzle during groove processing.

[0020] Figure 5 It is a figure which shows the inclination direction and inclination angle of the nozzle during groove processing.

[0021] Figure 6 It is a diagram showing the posture and trajectory of the nozzle when the tool diameter correction is not performed during groove processing.

[0022] Figure 7It is a diagram showing the posture and trajectory of the nozzle controlled by a conventional control device when the tool diameter correction is executed during groove processing.

[0023] Figure 8 It is a diagram showing the posture and trajectory of the nozzle controlled by the control device of this embodiment when the tool diameter correction is executed during groove processing.

[0024] Fig. 9 This is a diagram showing a laser irradiation area when the inclination angle of the nozzle is changed during groove processing.

[0025] Fig.10 This is a diagram showing a conventional laser irradiation area when tool diameter correction is performed during groove processing.

[0026] Fig.11 This is a diagram showing the laser irradiation area of ​​the present embodiment when tool diameter correction is performed during groove processing.

[0027] Fig.12 This is a diagram showing the trajectory of the nozzle when the tool diameter correction is not performed in the arc-shaped machining program path.

[0028] Fig.13 This is a diagram showing the trajectory of the nozzle when the tool diameter correction is executed in the arc-shaped machining program path and the inclination direction of the nozzle is set to the inclination direction with respect to the arc-shaped machining program path.

[0029] Fig.14 This figure shows the trajectory of the nozzle when tool diameter correction is performed when the radius difference between the arc-shaped machining program path and the tool center path is large and the nozzle tilt direction is set to the tilt direction relative to the arc-shaped machining program path.

[0030] Fig.15 The diagram shows machining shapes when the nozzle is tilted in an arc-shaped machining program path and when the nozzle is tilted in an arc-shaped machining program path relative to the tool center path. DETAILED DESCRIPTION

[0031] Hereinafter, one embodiment of the present disclosure will be described in detail with reference to the drawings.

[0032] Figure 1 This is a functional block diagram showing the structure of a laser processing machine control device 1 according to an embodiment of the present disclosure. The laser processing machine control device 1 according to this embodiment performs groove processing on a workpiece to be processed by the laser processing machine, thereby processing a component having a groove.

[0033] Here, refer to Figure 2 to Figure 6The groove processing using a laser processing machine is explained in detail. Figure 2 This is a diagram for explaining groove processing, and is a three-dimensional diagram of a groove-processed product P. Figure 2 In the example shown, the grooved finished product P in the shape of a quadrangular pyramid has a shape in which the side surfaces on all four sides are inclined outward toward the upper surface side. The groove formed by such inclined surfaces forms a groove portion during laser welding.

[0034] Figure 3 2 is a diagram for explaining groove processing, and is a stereoscopic diagram showing the posture and trajectory of the nozzle 2 during groove processing. Figure 4 2 is a diagram for explaining groove processing, and is a top view showing the trajectory of the nozzle 2 during groove processing. Figure 3 and Figure 4 The example shown shows the machining of a workpiece W into Figure 2 The trajectory of the nozzle 2 in the case of the groove processing completed product is shown.

[0035] like Figure 3 and Figure 4 As shown in FIG. 1 , the nozzle 2 is moved in a rectangular shape on the surface side of the workpiece W. At this time, the nozzle 2 is tilted relative to the moving direction of the nozzle 2. Figure 3 and Figure 4 In the example shown, the nozzle 2 is tilted 90 degrees relative to the traveling direction ( Figure 3 X direction or Y direction) and tilted outward. Figure 3 as well as Figure 4 In the example shown, the direction ( Figure 3 The inclination angle of the nozzle 2 toward the above-mentioned inclination direction (Z direction) is set to 45 degrees.

[0036] Reference Figure 5 The inclination direction and inclination angle of the nozzle 2 will be described in more detail. Figure 5 2 is a diagram showing the inclination direction and inclination angle of the nozzle 2 during groove processing. Figure 5 In the example shown, the tilt direction of the nozzle 2 is the direction rotated 90 degrees with respect to the X direction, which is the moving direction of the nozzle 2, i.e., the Y direction. In addition, the tilt angle of the nozzle 2 from the Z direction, which is the direction perpendicular to the surface of the workpiece W (XY plane), to the Y direction, which is the tilt direction, is set to 60 degrees in the plane orthogonal to the X direction, which is the moving direction of the nozzle 2, i.e., the YZ plane. In this way, the tilt direction and tilt angle of the nozzle 2 are controlled during groove processing.

[0037] Here, the inclination angle of the nozzle 2 is sometimes changed in accordance with the processing shape according to the processing program instruction. If the inclination angle of the nozzle 2 is changed, the irradiation area of ​​the laser on the workpiece W to be processed changes. Therefore, the irradiation distance of the laser is adjusted by the tool diameter correction function generally provided in the control device 1 of the laser processing machine. That is, if the tool diameter correction is performed, Figure 3 as well as Figure 4 As shown, the tool center path through which the center of the nozzle 2 passes is offset from the machining program path, and the two become different paths. The offset amount is the tool diameter correction amount.

[0038] Figure 6 It is a diagram showing the posture and trajectory of the nozzle 2 when the tool diameter correction is not performed during groove processing. Figure 6 The posture and trajectory of the nozzle 2 as viewed from the XY plane are shown. Figure 6 In the example shown, the tool diameter correction is not performed, and the machining program path is consistent with the tool center path. Moreover, even at the curved corners of these paths, the nozzle 2 is controlled so that the tilt direction of the nozzle 2 relative to the machining program path is always constant, so the nozzle 2 automatically rotates to maintain the tilt direction of the nozzle 2.

[0039] Figure 7 2 is a diagram showing the posture and trajectory of the nozzle 2 controlled by a conventional control device when tool diameter correction is performed during groove processing. Figure 7 As shown in FIG. 1 , the inclination direction of the nozzle 2 controlled by the conventional control device is automatically controlled to be constant as the inclination direction relative to the tool center path. If the tool diameter correction amount is changed (the tool diameter correction function is turned on) in correspondence with the change in the inclination angle of the nozzle 2 according to the machining shape, the travel direction of the tool center path changes, and the inclination direction of the nozzle 2 changes accordingly. Therefore, the following problem arises: the inclination direction of the nozzle relative to the machining program path changes, and the machining accuracy decreases.

[0040] Therefore, the control device 1 of the laser processing machine of the present embodiment solves the above-mentioned problems. Hereinafter, the configuration of the control device 1 of the laser processing machine of the present embodiment will be described in detail.

[0041] return Figure 1 The control device 1 of the laser processing machine of this embodiment includes: a processing program analysis unit 11, a tool center path calculation unit 12, an inclination direction calculation unit 13, a tool posture calculation unit 14, a drive axis movement amount calculation unit 15 and a drive axis control unit 16.

[0042] The laser processing machine control device 1 of the present embodiment is realized by, for example, causing a computer having a CPU, a memory, etc. to read a program for executing the laser processing of the present embodiment. The laser processing machine control device 1 of the present embodiment includes a numerical control device and a servo control device.

[0043] The processing program analyzing unit 11 analyzes the input processing program. Specifically, the processing program analyzing unit 11 analyzes the processing program to obtain processing information such as the processing program path, information on the tilt direction of the nozzle, and the tilt angle of the nozzle.

[0044] The tool center path calculation unit 12 generates an offset vector for the machining program path based on the analysis result of the machining program by the machining program analysis unit 11, and calculates the tool center path through which the center of the nozzle passes based on the offset vector. The tool center path calculation unit 12 calculates the tool center path offset from the machining program path (by the amount of the tool diameter) to correct the tool diameter.

[0045] The tilt direction calculation unit 13 includes a first tilt direction calculation unit 131 , a second tilt direction calculation unit 132 , and a tilt direction calculation switching unit 133 .

[0046] The first inclination direction calculation unit 131 calculates the inclination direction of the nozzle relative to the machining program path based on the analysis result of the machining program by the machining program analysis unit 11. Specifically, based on the information related to the inclination direction of the nozzle 2 (the rotation angle relative to the moving direction of the nozzle 2) obtained by the machining program analysis unit 11, the inclination direction of the nozzle 2 relative to the machining program path is calculated.

[0047] The second inclination direction calculation unit 132 calculates the inclination direction of the nozzle relative to the tool center path based on the analysis result of the machining program by the machining program analysis unit 11. Specifically, based on the information related to the inclination direction of the nozzle 2 (the rotation angle relative to the moving direction of the nozzle 2) obtained by the machining program analysis unit 11, the inclination direction of the nozzle 2 relative to the tool center path is calculated.

[0048] The inclination direction calculation switching unit 133 switches between the calculation of the inclination direction of the nozzle 2 relative to the machining program path by the first inclination direction calculation unit 131 and the calculation of the inclination direction of the nozzle 2 relative to the tool center path by the second inclination direction calculation unit 132, in accordance with the shape of the machining program path. Specifically, when the shape of the machining program path is an arc shape, the inclination direction calculation switching unit 133 switches to the calculation of the inclination direction of the nozzle 2 relative to the tool center path by the second inclination direction calculation unit 132. The switching of the inclination direction calculation by the inclination direction calculation switching unit 133 will be described in detail later.

[0049] In addition, the nozzle 2 is preferably tilted in a direction perpendicular to the machining program path. Similarly, the nozzle 2 is preferably tilted in a direction perpendicular to the tool center path. Thus, so-called normal direction control can be performed.

[0050] The tool posture calculation unit 14 calculates the posture of the nozzle 2 based on the inclination direction of the nozzle 2 calculated by the first inclination direction calculation unit 131 or the second inclination direction calculation unit 132 and the inclination angle of the nozzle 2 from the direction perpendicular to the plane of the workpiece W to the inclination direction in a plane orthogonal to the machining program path.

[0051] The drive axis movement amount calculation unit 15 calculates the movement amount of the drive axis based on the tool center path calculated by the tool center path calculation unit 12 and the posture of the nozzle 2 calculated by the tool posture calculation unit 14 .

[0052] The drive shaft control unit 16 controls the drive shaft according to the movement amount of the drive shaft calculated by the drive shaft movement amount calculation unit 15 .

[0053] Next, the operation of the nozzle 2 of the laser processing machine controlled by the control device 1 of the laser processing machine according to the present embodiment will be described in detail.

[0054] Figure 8 1 is a diagram showing the posture and trajectory of the nozzle 2 controlled by the control device 1 of this embodiment when the tool diameter correction is performed during groove processing. Figure 8 As shown, in the control device 1 of the present embodiment, when the tool diameter correction amount is changed corresponding to the change in the inclination angle of the nozzle 2 according to the machining shape, etc. (the tool diameter correction function is turned on), the inclination direction of the nozzle 2 is controlled to be the inclination direction relative to the machining program path. Therefore, the inclination direction of the nozzle 2 relative to the machining program path is always maintained constant, so that the machining accuracy can be improved.

[0055] Fig. 9 2 is a diagram showing the laser irradiation area LA when the inclination angle of the nozzle 2 is changed during groove processing. Fig. 9 In the figure, when the tool diameter correction is turned off, the machining program path and the tool center path are originally consistent, but for convenience, Fig. 9 The two are recorded alternately. Fig. 9 As shown, it can be seen that if the inclination angle of the nozzle 2 is changed, specifically, if the inclination of the posture of the nozzle 2 is increased, the irradiation area LA of the laser beam is expanded.

[0056] In contrast, Fig.10: is a diagram showing a conventional laser irradiation area LA when tool diameter correction is performed during groove processing. It can be seen that in the past, if the inclination angle of the nozzle 2 is changed so that the tool diameter correction is turned on, the inclination direction of the nozzle 2 is controlled to be the inclination direction relative to the tool center path offset from the processing program path, so the inclination direction changes with the tool center path, and the irradiation method of the laser on the workpiece W also changes. As a result, the laser irradiation area LA also changes significantly, which becomes a cause of reduced processing accuracy.

[0057] In contrast, Fig.11 FIG. 4 is a diagram showing the laser irradiation area LA of the present embodiment when tool diameter correction is performed during groove processing. Fig.11 As shown, if the inclination angle of the nozzle 2 is changed so that the tool diameter correction is turned on, the inclination direction of the nozzle 2 is controlled to be the inclination direction relative to the machining program path, so the inclination direction of the nozzle 2 relative to the machining program path is maintained. Therefore, it is possible to avoid a decrease in machining accuracy.

[0058] Next, refer to Figure 12 to Figure 15 The switching of the tilt direction calculation by the tilt direction calculation switching unit 133 will be described in detail.

[0059] Fig.12 FIG. 1 is a diagram showing laser processing when tool diameter correction is not performed in an arc-shaped processing program path. Fig.12 As shown, when groove processing is performed on an arc-shaped processing program path, groove processing is performed while controlling the tilt direction of the nozzle 2 so that the tilt direction is always perpendicular (normal direction) to the tangent of the arc. Fig.12 , it is shown that the tool diameter correction is not performed, so the machining program path is consistent with the tool center path.

[0060] Fig.13 FIG. 1 is a diagram showing laser processing when tool diameter correction is performed in an arc-shaped processing program path and the nozzle is tilted in the direction relative to the arc-shaped processing program path. Fig.13 As shown in FIG. 1 , if the nozzle 2 is moved on the tool center path with the inclination direction of the nozzle 2 being the inclination direction relative to the machining program path, a difference in inclination occurs between the inclination of the normal line relative to the tangent line of the tool center path and the inclination of the normal line relative to the tangent line of the program path, especially near the starting point and the end point of the path. In this case, even if the path is a perfect circle, the shape of the machined surface will not be a perfect circle.

[0061] in addition, Fig.14 This figure shows laser machining when tool diameter correction is performed in an arcuate machining program path and the inclination direction of the nozzle 2 is set to the inclination direction relative to the arcuate machining program path when the radius difference with the tool center path is large. Fig.15 The diagrams show machining shapes when the nozzle 2 is tilted in the arc-shaped machining program path and when the nozzle 2 is tilted in the arc-shaped machining program path. Fig.14 as well as Fig.15 As shown, it can be seen that when the radius difference between the machining program path and the tool center path is large, if the inclination direction of the nozzle 2 is set to the inclination direction relative to the machining program path, the machining shape is not an arc shape, and as the radius difference becomes larger, the machining shape is not a curve shape.

[0062] Therefore, in this embodiment, the calculation of the inclination direction of the nozzle 2 relative to the machining program path and the calculation of the inclination direction of the nozzle 2 relative to the tool center path are switched according to the shape of the machining program path by the inclination direction calculation switching unit 133. In particular, when the shape of the machining program path is an arc shape as described above, the calculation is switched to the inclination direction of the nozzle 2 relative to the tool center path. In this way, the desired machining shape can be maintained and the machining accuracy can be improved.

[0063] According to the control device 1 for a laser processing machine of the present embodiment, the following effects are obtained.

[0064] According to the present embodiment, a tool center path calculation unit 12 is provided, which calculates the tool center path based on the offset vector; and a first tilt direction calculation unit 131 is provided, which calculates the tilt direction of the nozzle 2 relative to the machining program path. In addition, a tool posture calculation unit 14 is provided, which calculates the posture of the nozzle 2 based on the calculated tilt direction of the nozzle 2 and the tilt angle of the nozzle 2 from the direction perpendicular to the plane of the workpiece W to the tilt direction in the plane orthogonal to the machining program path; a drive axis movement amount calculation unit 15 is provided, which calculates the movement amount of the drive axis based on the tool center path and the posture of the nozzle 2; and a drive axis control unit 16 is provided, which controls the drive axis based on the movement amount of the drive axis.

[0065] Thus, the nozzle tilt angle is changed according to the machining shape, etc., and even when the tool diameter correction amount is changed, the tilt direction of the nozzle 2 with respect to the machining program path can be maintained, thereby improving machining accuracy.

[0066] In addition, according to the present embodiment, a second inclination direction calculation unit 132 is provided, which calculates the inclination direction of the nozzle 2 relative to the tool center path based on the analysis result of the machining program. In addition, an inclination direction calculation switching unit 133 is provided, which switches the calculation of the inclination direction of the nozzle 2 relative to the machining program path by the first inclination direction calculation unit 131 and the calculation of the inclination direction of the nozzle 2 relative to the tool center path by the second inclination direction calculation unit 132 according to the shape of the machining program path.

[0067] Thus, the calculation of the tilt direction of the nozzle 2 relative to the tool center path or the calculation of the tilt direction of the nozzle 2 relative to the machining program path can be switched according to the shape of the machining program path, thereby maintaining the machining shape and improving the machining accuracy.

[0068] In addition, according to the present embodiment, when the shape of the machining program path is an arc shape, the inclination direction calculation switching unit 133 is switched to the calculation of the inclination direction of the nozzle 2 relative to the tool center path by the second inclination direction calculation unit 132. Thus, the machining shape can be maintained more reliably and the machining accuracy can be improved.

[0069] In addition, according to the present embodiment, the nozzle 2 is tilted in a direction perpendicular to the machining program path, and similarly, the nozzle 2 is tilted in a direction perpendicular to the tool center path, thereby enabling so-called normal direction control to be performed, thereby improving machining accuracy.

[0070] In addition, the present disclosure is not limited to the above-described embodiments, and modifications and improvements that can achieve the purpose of the present disclosure are also included in the present disclosure.

[0071] Explanation of symbols

[0072] 1 Laser processing machine control device

[0073] 2 Nozzles

[0074] 11 Processing program analysis department

[0075] 12 Tool center path calculation department

[0076] 13. Tilt direction calculation unit

[0077] 131 first tilt direction calculation unit

[0078] 132 Second tilt direction calculation unit

[0079] 133 Tilt direction calculation switching unit

[0080] 14 Tool posture calculation unit

[0081] 15 Drive axis movement calculation unit

[0082] 16 Drive shaft control unit

[0083] LA laser irradiation area

[0084] P Bevel processing finished product

[0085] W workpiece.

Claims

1. A control device for a laser processing machine having a nozzle, characterized in that: have: a tool center path calculation unit, which generates an offset vector relative to the machining program path based on the analysis result of the machining program, and calculates the tool center path through which the center of the nozzle passes based on the offset vector; a first tilt direction calculation unit, which calculates the tilt direction of the nozzle relative to the machining program path according to the analysis result of the machining program; a tool posture calculation unit that calculates the posture of the nozzle based on the tilt direction of the nozzle calculated by the first tilt direction calculation unit and the tilt angle of the nozzle from the direction perpendicular to the plane of the workpiece to the tilt direction in a plane orthogonal to the machining program path; a drive shaft movement amount calculation unit that calculates a movement amount of the drive shaft based on the tool center path calculated by the tool center path calculation unit and the posture of the nozzle calculated by the tool posture calculation unit; as well as A drive shaft control unit controls the drive shaft according to the movement amount of the drive shaft calculated by the drive shaft movement amount calculation unit.

2. The control device for a laser processing machine according to claim 1, characterized in that: The control device of the laser processing machine also has: a second inclination direction calculation unit that calculates an inclination direction of the nozzle relative to the tool center path based on an analysis result of the machining program; and An inclination direction calculation switching unit switches the calculation of the inclination direction of the nozzle relative to the machining program path performed by the first inclination direction calculation unit and the calculation of the inclination direction of the nozzle relative to the tool center path performed by the second inclination direction calculation unit in accordance with the shape of the machining program path.

3. The control device for a laser processing machine according to claim 2, characterized in that: When the shape of the machining program path is an arc shape, the inclination direction calculation switching unit switches to calculation of the inclination direction of the nozzle with respect to the tool center path by the second inclination direction calculation unit.

4. The control device for a laser processing machine according to claim 2 or 3, characterized in that: The inclination direction of the nozzle relative to the machining program path is a direction orthogonal to the machining program path. The tilt direction of the nozzle relative to the tool center path is a direction orthogonal to the tool center path.

Images