Workpiece machining method based on laser

Abstract

The invention relates to a laser-based workpiece machining method in which a defined workpiece surface (7 ', 37) is produced on a workpiece (1, 11, 21, 31, 41, 55) by removing material with a laser (52) using a laser machining device (50), which comprises a workpiece fixing device (54) for receiving and fixing the workpiece (1, 11, 21, 31, 41, 55); the moving device (51) is used for enabling the workpiece fixing device (54) to move relative to the device base (56); the invention relates to a laser machining device (50) for machining workpieces (1, 11, 21, 31, 41, 55), comprising a workpiece fixing device (54), and a laser (52), the laser beam (3 ', 13, 23, 33, 43, 53) of which is irradiated with its geometric beam axis (5', 15, 25, 35, 45) onto a workpiece (1, 11, 21, 31, 41, 55) accommodated in the workpiece fixing device (54), the laser machining device (50) being designed to align the workpiece (1, 11, 21, 31, 41, 55) arranged in the workpiece fixing device (54) with respect to the laser beam (3 ', 13, 23, 33, 43, 53), the beam axis (5', 15, 25, 35, 45) being aligned with the workpiece fixing device (54) during machining. 45) at the intersection with the tangent (17, 27, 38, 48) of the workpiece surface (7 ', 37) to be machined form an angle alpha between 1 DEG and 10 DEG.

Description

[0001] The invention relates to a workpiece processing method based on laser.

[0002] As is known, machining of workpieces uses short, intense laser pulses. Laser radiation with a high power density heats the material on the workpiece surface. The workpiece surface reaches very high temperatures locally, causing the workpiece material to evaporate or sublime. Under the high power density of the laser, the electrons and ions of the removed material form a plasma. Material removal is also called laser ablation or laser vaporization. For example, material can be removed in layers over large areas. It is also possible to cut workpieces using continuous or pulsed laser radiation. This is called laser cutting or laser beam cutting. The parameters of the laser radiation must be adapted to the material to be processed and the desired processing process. The parameters of the laser radiation are the wavelength and the average power and, in the case of pulsed laser radiation, the pulse energy and the pulse duration.

[0003] During laser processing, the laser beam and the workpiece are aligned relative to each other in a defined manner and, if necessary, moved in order to specifically remove material from a predetermined area of ​​the workpiece and to form certain contours on the workpiece surface. This includes forming cutting edges or other edges on the workpiece.

[0004] A laser processing machine is equipped with a laser that generates a laser beam. The laser beam extends along a beam axis. The beam axis corresponds to a geometrical straight line. The laser processing machine comprises a laser head that irradiates the laser beam onto the workpiece with its beam axis as the axis. If necessary, the laser beam can also be moved within a predetermined contour on the surface of the workpiece. The workpiece is mounted in a device for alignment and positioning, which is also called a clamping device on a machine tool. The device is equipped with a device base, a workpiece fixture and a moving device. The device base is fixed in place. It can be part of the machine base of the laser processing machine. The workpiece fixture fixes the workpiece and clamps it firmly so that the position of the workpiece relative to the workpiece fixture does not change while the workpiece is being processed. The moving device ensures that the workpiece fixture moves relative to the device base. Since the laser head of a laser processing machine is usually in a fixed position relative to the device base, the moving device also ensures relative movement between the laser head and the workpiece fixture. Therefore, the workpiece clamped in the workpiece fixture can be moved relative to the laser beam generated by the laser head. Due to the relative movement caused by the moving device, the entire surface of the workpiece can be processed as long as the workpiece surface is not covered by the workpiece fixture. During processing, the workpiece surface is aligned with the laser beam at different angles. The laser head can be equipped with a deflection device, which deflects the laser beam via optical elements and guides it at high speed over the workpiece surface. The deflection device thus ensures an additional relative movement between the laser beam and the workpiece.

[0005] When machining a workpiece, the beam axis of the laser beam is usually aligned with the workpiece to be machined so that the beam axis is perpendicular to the workpiece surface. As shown in FIG. 1. FIG. 1 shows a workpiece 1 and a laser beam 3 having a beam axis 5. FIG. 2 and FIG. 3 show the impact point 2 where the laser beam 3 impacts the plane 1a of the workpiece 1. The energy density at the center of the laser beam 3 is greater than that at the edge, so the temperature at the center of the laser beam 3 is higher than that at the edge. Therefore, more material is removed from the workpiece at the center of the impact point 2 than at the edge of the impact point 2. If the laser beam 3 does not move relative to the workpiece 1, the laser beam 3 forms a circular depression 4 on the surface of the workpiece 1. The center of the depression 4 is deeper than the edge. Under the action of the laser beam 3, a cloud or flame 8 is formed on the surface of the workpiece 1, which contains evaporated or sublimated workpiece material as well as dust and other particles. FIG. 4 shows that the flame 8 has an opening angle. When the laser beam 3 moves relative to the workpiece along a path on the surface 1a of the workpiece 1, a series of spatially offset depressions 4 are generated, which together form a groove 10. An edge 9 is formed at the transition between the plane 1a and the groove 10. The opening angle of the groove 10 is γ. If an edge, such as a cutting edge, is to be produced on the workpiece 1 by means of the laser beam 3, or if a workpiece is to be cut, the laser beam 3 is moved back and forth several times along a path relative to the workpiece 1 until the groove 10 has reached the desired depth. With each movement, the groove 10 formed by the laser beam 3 becomes deeper and wider. This is shown in Figures 7 and 8. These two figures show that the grooves 10 merge into furrows 10' due to the removal of additional material by the laser beam. Figure 8 shows in particular that the furrows 10 are not only deeper but also wider due to the opening angle γ of the flame 8. Each time the laser beam 3 moves along the path, the edge 9 formed by the edge of the flame 8 on the surface 1a of the workpiece 1 moves to both sides. Therefore, at the end of the laser processing, the edge 9 is not necessarily in the predetermined position. The surface 7 moves accordingly. In addition, dust and sublimated material from the workpiece 1 are deposited on the surface 1a in the area of ​​the edge of the flame 8. This leads to a poorer surface quality of the workpiece in the area of ​​the edge 9.

[0006] The task of the present invention is to provide a laser-based workpiece processing method, by which a workpiece surface can be processed at an accurate predetermined position, and the processed workpiece surface has a high surface quality.

[0007] This problem can be solved by a method according to claim 1. The method according to the invention is characterized in that the workpiece and the laser beam are relatively aligned so that during the machining process, the geometrical beam axis of the laser beam forms an angle α of 1° to 10° with the tangent of the surface of the workpiece to be machined at the intersection of the beam axis and the surface of the workpiece to be machined. Therefore, the cloud or flame formed on the surface of the workpiece under the action of the laser beam also has an opening angle inclined relative to the surface of the workpiece. Advantageously, the angle α coincides with the opening angle of the flame. The angle α between the beam axis of the laser beam and the tangent of the surface of the workpiece to be machined prevents vaporized or sublimated material from being deposited on the surface of the workpiece to be machined and prevents the surface of the workpiece from being charred in an undesirable manner. After laser machining, the adjacent surface of the generated edge has a good surface quality.

[0008] Another advantage of the method according to the invention is that by using the laser to remove material in a targeted manner, a workpiece surface can be produced at a specific location with a precisely defined geometry. Unlike known methods, the workpiece surface formed by the material removal does not move during the laser processing.

[0009] During laser machining, material is not removed layer by layer, as the laser is not perpendicular to the surface of the workpiece being machined. Instead, a portion of the workpiece is cut away to form the workpiece surface.

[0010] According to a preferred embodiment of the present invention, during the laser machining process, the laser beam and the workpiece are moved relative to each other so that a portion of the workpiece is removed. If the thickness of the portion to be removed is small, the material removed from the workpiece will be completely vaporized. During the material removal process, the surface of the workpiece to be machined is formed at the interface of the removed portion of the workpiece. The material is removed along a predetermined path while keeping the axis of the beam aligned at an angle α relative to the tangent of the workpiece surface. In this way, the workpiece can be cut or an edge can be made. To this end, the laser beam is guided along the path multiple times until the desired workpiece surface is completely formed.

[0011] According to another preferred embodiment of the present invention, the angle α is determined according to the workpiece material, the laser wavelength and the laser average power. The above parameters determine the opening angle γ of the flame formed on the workpiece surface under the action of the laser beam.

[0012] According to another preferred embodiment of the invention, the laser is a pulsed laser. With a pulsed laser, a particularly high energy density can be obtained within a short pulse duration, thereby generating a particularly high surface temperature on the workpiece. During a short pulse duration, the temperature is not significantly conducted inside the workpiece during the short pulse duration, since the energy transfer in the heat conduction process is very slow compared to the pulse duration. Therefore, the energy transmitted by the laser beam to the workpiece is only concentrated in a very thin layer. Therefore, when using a pulsed laser, the workpiece surface reaches a particularly high temperature in a limited area and the material suddenly vaporizes.

[0013] According to another preferred embodiment of the present invention, when pulse laser is used, the angle α depends not only on the workpiece material, the laser wavelength and the average laser power, but also on the pulse duration and pulse energy of the pulse laser.

[0014] According to another preferred embodiment of the invention, the laser beam is used to generate a flame on the workpiece surface, the flame containing the sublimated material of the workpiece, wherein the opening angle γ of the flame depends on the material of the workpiece and the laser beam. The angle α between the beam axis of the laser beam and the tangent of the workpiece surface to be processed is set to correspond to the angle γ. In this way, a workpiece surface of particularly good quality can be processed.

[0015] According to another preferred embodiment of the present invention, the laser beam is focused on the workpiece, wherein the focal points of the focused laser beam are respectively located at the intersection points of the beam axis and the surface of the workpiece to be processed.

[0016] According to another preferred embodiment of the present invention, the workpiece surface to be processed is a plane.

[0017] According to another preferred embodiment of the present invention, the surface of the workpiece to be processed is a curved surface. During the laser material removal process, the moving device rotates the workpiece in the workpiece fixture around the workpiece rotation axis.

[0018] According to another preferred embodiment of the present invention, the laser beam is aligned at a constant angle α relative to the workpiece while removing material from the workpiece. Therefore, the collimation of the laser beam relative to the workpiece remains constant throughout the material removal process. This method is suitable, for example, for machining a flat surface if the workpiece has a certain symmetry relative to the moving axis of the moving device of the laser machining device.

[0019] According to another preferred embodiment of the invention, the angle α changes within an angular range of 1°≤α≤10° as material is removed from the workpiece. In this way, the collimation of the laser beam relative to the workpiece changes, wherein the angle α is kept within a predetermined angular range. This angular change occurs if the laser beam is additionally guided along the laser path on a closed or open curve during the material removal process, if irregular shapes or non-planar surfaces are generated, or if the workpiece is arranged in a specific orientation relative to the axis of motion of the moving device of the laser processing device. Of particular importance here is the workpiece rotation axis, about which the workpiece fixture rotates and thus also the workpiece rotates around the workpiece fixture.

[0020] According to another preferred embodiment of the present invention, the laser beam moves relative to the workpiece surface, wherein during the relative movement, the angle α between the axis of the laser beam and the tangent of the workpiece surface is within an angle range of 1≤α≤10°. The relative movement is a superposition of a first movement and a second movement. The first movement moves the laser beam between a first point A on the workpiece surface and a second point B on the workpiece surface. In the second movement, the laser beam moves within a closed or open curve, the range of the curve being smaller than the distance of the laser beam from point A to point B. The additional annular second movement increases the material removal area of ​​the first movement.

[0021] Further advantages and preferred embodiments of the invention can be seen from the following description, the drawings and the claims.

[0022] Attached photos

[0023] The figure shows a known laser-based workpiece processing method and a laser-based processing method according to the present invention.

[0024] FIG1 is a perspective view of a laser beam irradiating a workpiece in a known laser processing method,

[0025] FIG. 2 is another perspective view of the workpiece shown in FIG. 1 ,

[0026] FIG3 is a longitudinal sectional view of the workpiece shown in FIG1 and FIG2 along the plane marked AA in FIG2,

[0027] FIG. 4 is a cross-sectional view of the workpiece shown in FIG. 3 , wherein the flame contains sublimated material.

[0028] FIG5 is a workpiece shown in FIGS. 1 to 4 wherein a laser beam is used to create depressions along a path,

[0029] FIG. 6 is a front view of the workpiece shown in FIG. 5 ,

[0030] Figure 7 is a perspective view of the workpiece, with the laser beam moving multiple times along the path.

[0031] FIG8 is a front view of the workpiece shown in FIG7 ,

[0032] Fig. 9 is a workpiece having a laser beam aligned according to the invention,

[0033] Fig.10 yes Fig. 9 Longitudinal section of a workpiece during laser processing.

[0034] Fig.11 A second workpiece is machined into a planar workpiece using the method of the present invention,

[0035] Fig.12 is based on Fig.11 The machined workpiece has some material removed.

[0036] Fig.13 yes Fig.11 The workpiece in the workpiece, the material has been completely removed,

[0037] Fig.14 A third workpiece having a planar workpiece surface machined using the method of the present invention,

[0038] Fig.15 is based on Fig.14 The workpiece being machined has some material removed.

[0039] Fig.16 Yes Fig.14 The workpiece shown has had all the material removed.

[0040] Fig.17 A fourth workpiece having an arc-shaped workpiece surface machined according to the method of the present invention,

[0041] Fig.18 is based on Fig.17 The workpiece being machined has some material removed.

[0042] Fig.19 Yes Fig.17 The workpiece shown has had all the material removed.

[0043] Fig. 20 The fifth workpiece is processed into a curved workpiece surface by the method of the present invention. The workpiece in the figure is a front view at the beginning of laser processing.

[0044] Fig.21 yes Fig. 20 A perspective view of the workpiece shown,

[0045] Fig. 22 yes Fig. 20 The workpiece shown is at the first point in time after the laser processing.

[0046] Fig.23 yes Fig. 22 A perspective view of the workpiece shown,

[0047] Fig.24 yes Fig. 20 The workpiece shown is at a second point in time after laser processing.

[0048] Fig.25 yes Fig.24 A perspective view of the workpiece shown,

[0049] Fig.26 yes Fig. 20 The workpiece shown is at the third time point in the later stage of laser processing.

[0050] Fig. 27 yes Fig.26 A perspective view of the workpiece shown,

[0051] Fig.28 It is a laser processing machine for implementing the method. DETAILED DESCRIPTION

[0052] 1 to 8 show a known laser-based workpiece processing method, in which the beam axis 5 of the laser beam 3 is perpendicular to the plane 1a of the workpiece 1. This known method has been described in the introduction above.

[0053] Fig. 9 and Fig.10 The method of the present invention is shown. The workpiece surface 7' to be processed is a plane. Therefore, the tangent line of the workpiece surface extends on the surface. In this embodiment, the workpiece surface 7' to be processed is perpendicular to the workpiece surface 1a. Different from the known method shown in Figures 1 to 8, in Fig. 9 and Fig.10 In the method of the present invention shown, the beam axis 5' of the laser beam 3' is not parallel to the surface 7' to be processed, nor is it at 90° to the plane 1a of the workpiece 1, but is at an angle α to the plane workpiece surface 7' to be processed. Fig.10 The cloud or flame 8' generated when the laser beam 3' strikes the workpiece 1 is shown, which contains the sublimated material of the workpiece 1. The flame 8' has an opening angle γ. This angle γ is not exactly equivalent to the opening angle of the cone flame, but only to the opening angle of the cone flame relative to the beam axis 5. When the laser beam is aligned with the beam axis 5', the angle α corresponds to the angle γ. This ensures that Fig.10 As shown, the left side of the flame 8' is parallel to the workpiece surface 7' to be machined. This means that the laser beam 3' can be used to produce a precise surface 7', wherein the edge between the surface 7' and the surface 1a does not move during the laser machining process.

[0054] Figures 11 to 13 A second workpiece 11 is shown, on which a predetermined workpiece surface 17 is machined using the method of the present invention. The workpiece 11 is cylindrical and has a circular cross section. Figures 11 to 13 As shown. The workpiece 11 has an insert 12, on which a predetermined planar workpiece surface is formed by material removal using a laser beam 13 having a beam axis 15. For this purpose, a portion of the insert 12 is removed. The laser beam 13 is directed with its beam axis 15 toward the workpiece 11, so that the beam axis 15 forms an angle α with a tangent 17 of the workpiece surface to be machined. Fig.12 Shown is the workpiece 11 after a portion of the insert 12 has been removed using a laser beam 13 . Fig.13 The workpiece is shown at the end of laser processing. The surface of the workpiece to be processed is a flat surface. Figures 11 to 13It is shown that the angle α remains constant during the entire laser process. This allows, for example, a smooth surface to be produced on the cutting tool.

[0055] Figures 14 to 16 A third workpiece 21 with an insert 22 is shown, on which a predetermined planar workpiece surface can be machined using the method of the present invention. Since the workpiece surface to be machined is a plane, a tangent line 27 of the workpiece surface extends on the workpiece surface. The beam axis 25 of the laser beam 23 makes an angle α with the tangent line 27 of the workpiece surface to be machined. In line with the second workpiece 11, the third workpiece 21 is cylindrical and has a circular cross section. Unlike the second workpiece 11, the insert 22 of the third workpiece 21 is inserted into the workpiece in a different direction.

[0056] Figures 17 to 19 A fourth workpiece 31 is shown, on which there is an insert 32, on which a curved workpiece surface is to be machined, Fig.17 The curve 37 in FIG. 3 shows the direction of the curved workpiece surface. For this purpose, during the laser processing, the workpiece 31 is rotated about its longitudinal axis. The laser beam 33 is always aligned with its beam axis 35 at an angle α to the tangent 38 of the curved surface. During the material removal process, the angle α remains constant. In this way, for example, a guide phase can be generated on the cutting tool.

[0057] Figures 20 to 27 A fifth workpiece 41 is shown, which has two inserts 42 and 42a on which arc-shaped workpiece surfaces are to be machined. Here, the beam axis 45 of the laser beam 43 and the tangent line 48 always form an angle α at the intersection of the beam axis 45 and the workpiece surface when the laser beam irradiates the surface of the workpiece 41. The inserts 42 and 42a are special in that they are not parallel to the longitudinal axis of the workpiece 41. Therefore, when laser processing is performed using the laser beam 43, the workpiece 41 is rotated about its longitudinal axis. The rotation is for machining the arc-shaped workpiece surface on a plane perpendicular to the longitudinal axis of the workpiece 41, and for machining the workpiece surface of the inserts 42 and 42a in the axial direction of the workpiece 41. Fig. 20 and 21 Two different views of a workpiece 41 at the start of laser processing are shown. Here, the beam axis 45 of the laser beam 43 makes an angle α1 with a tangent line 48 to the surface of the insert 42 of the workpiece 41 . Fig. 22 and Fig.23 A workpiece 41 is shown at a later stage of laser processing. Fig.23 It is shown that the laser beam 43 is moved with its beam axis 35 along an insert 42 of a workpiece 41. The beam axis 45 of the laser beam 43 forms an angle α2 with a tangent 48 to the workpiece surface, which angle is different from α1. Fig.24 and 25The workpiece 41 is shown at a later stage of laser processing. The laser beam 43 continues to move along the surface of the insert 42 of the workpiece 41. The beam axis 45 of the laser beam 43 makes an angle α3 with a tangent line 48 of the workpiece surface. Fig.26 and 27 The workpiece 41 is shown with the insert 42 shortly before the end of the laser processing. At this time, the laser beam 43 is located at the lower end of the insert 42, and the beam axis 45 of the laser beam 43 forms an angle α4 with the tangent 48. The angles α1, α2, α3 and α4 are different, but are between 1° and 10°. In this case, α1<α2<α3<α4 applies. Figures 20 to 27 It is shown that the angle between the beam axis 45 of the laser beam 43 and the tangent 48 of the workpiece surface 41 changes during laser processing, wherein the angle is always between 1° and 10°.

[0058] Fig.28 A laser processing device 50 for performing the method is shown. The laser processing device 50 comprises a workpiece fixture 54 for receiving and fixing a workpiece 55, a moving device 51 for moving the workpiece 55 in the fixture relative to a device base 56, and a laser 52 for generating a laser beam 53 and moving it by a laser scanning device. In this case, the moving device 51 has three linear axes X, Y, Z and two rotation axes B and C.

[0059] All features of the present invention may be essential features of the present invention and may be used individually or in combination with each other.

[0060] Reference numerals

[0061] 1 Workpiece

[0062] 1a Plane of workpiece

[0063] 2 Laser beam impact point

[0064] 3,3' laser beam

[0065] 4,4' recess

[0066] 5,5' beam axis

[0067] 7,7'Generated workpiece surface

[0068] 8,8' Flame

[0069] 9 Edge

[0070] 10,10' groove

[0071] 11 Second Workpiece

[0072] 12 Inserts

[0073] 13 Laser Beam

[0074] 15 Beam axis

[0075] 17 Workpiece surface tangent

[0076] 21 Second Workpiece

[0077] 22 Insert

[0078] 23 Laser Beam

[0079] 25 beam axis

[0080] 27 Workpiece surface tangent

[0081] 31 Second Workpiece

[0082] 32 Inserts

[0083] 33 Laser Beam

[0084] 35 beam axis

[0085] 37 Trajectory of the workpiece surface

[0086] 38 Tangent

[0087] 41 The Fifth Artifact

[0088] 42 Inserts

[0089] 42a Insert

[0090] 43 Laser Beam

[0091] 45 beam axis

[0092] 48 Tangent

[0093] 50 Laser processing equipment

[0094] 51 Mobile Devices

[0095] 52 Laser

[0096] 53 Laser Beam

[0097] 54 Workpiece Fixing Device

[0098] 55 Workpiece

[0099] 56 Device base

Claims

1. A method for laser-based workpiece processing, wherein a laser processing device (50) is used to remove material with a laser (52) to produce a defined workpiece surface (7', 37) on a workpiece (1, 11, 21, 31, 41, 55), the laser processing device (50) comprising a workpiece fixture (54) for accommodating and fixing the workpiece (1, 11, 21, 31, 41, 55); a moving device (51) for moving the workpiece fixture (54) relative to a device base (56); and a laser (52), the laser beam (3', 13, 23, 33, 43, 53) of the laser being arranged to move the workpiece fixture (54) relative to a device base (56); Its geometrical beam axis (5', 15, 25, 35, 45) irradiates a workpiece (1, 11, 21, 31, 41, 55) accommodated in the workpiece fixture (54), wherein the laser processing device (50) is designed to align the workpiece (1, 11, 21, 31, 41, 55) arranged in the workpiece fixture (54) relative to the laser beam (3', 13, 23, 33, 43, 53) and to move the laser beam (3', 13, 23, 33, 43, 53) relative to the workpiece (1, 11, 21, 31, 41, 55), characterized in that The following method steps: The workpiece (1, 11, 21, 31, 41, 55) and the laser beam (3', 13, 23, 33, 43, 53) of the laser (52) are aligned relative to each other so that the beam axis (5, 15, 25, 35, 45) of the laser beam (3', 13, 23, 33, 43, 53) forms an angle α with a tangent (17, 27, 38, 48) to the workpiece surface (7', 37) at the intersection of the beam axis (5', 15, 25, 35, 45 and the workpiece surface (7', 37) during machining, which is between 1° and 10°; The laser beam (3', 13, 23, 33, 43, 53) is aligned at the angle α relative to the workpiece (1, 11, 21, 31, 41, 55) to remove material from the workpiece (1, 11, 21, 31, 41, 55), wherein 1°≤α≤10°.

2. The method according to claim 1, characterized in that: During the laser processing, the laser beam (3, 13, 23, 33, 43, 53) and the workpiece (1, 11, 21, 31, 41, 55) move relative to each other, so that a portion of the workpiece (1, 11, 21, 31, 41, 55) is removed, wherein a surface (7, 37) of the workpiece to be processed is formed at the interface with the removed portion.

3. The method according to claim 1 or 2, characterized in that: The angle α depends on the material of the workpiece (1, 11, 21, 31, 41, 55), the wavelength of the laser (52) and the average power of the laser (52).

4. The method according to claim 1, 2 or 3, characterized in that: The laser (52) is pulsed.

5. The method according to claim 4, characterized in that The angle α depends on the pulse duration and the pulse energy.

6. The method according to any one of the preceding claims, characterized in that When the laser beam (3', 13, 23, 33, 43, 53) is irradiated onto the workpiece (1, 11, 21, 31, 41, 55), a flame (8') is generated, the flame containing the material of the workpiece (1, 11, 21, 31, 41, 55) sublimated by the laser beam (3', 13, 23, 33, 43, 53), wherein an opening angle γ of the flame (8') depends on the material of the workpiece (1, 11, 21, 31, 41, 55) and the laser beam (3', 13, 23, 33, 43, 53), and the angle α is set to be as large as the opening angle γ.

7. The method according to any one of the preceding claims, characterized in that The laser beam (3, 13, 23, 33, 43, 53) is focused on the workpiece (1, 11, 21, 31, 41, 55), wherein the focal points of the focused laser beam (3', 13, 23, 33, 43, 55) are respectively located at the positions where the beam axis (5', 15, 25, 35, 45) intersects with the surface (7', 37) of the workpiece to be processed.

8. The method according to any one of the preceding claims, characterized in that The surface (7) of the workpiece to be processed is a plane.

9. The method according to any one of claims 1 to 7, characterized in that The workpiece surface (37) to be processed is an arcuate surface. During the laser material removal process, the moving device causes the workpiece (31) accommodated in the workpiece fixing device to rotate around the workpiece rotation axis.

10. The method according to any of the preceding claims, characterized in that Removal of material from the workpiece (1, 11, 21, 31, 41, 55) is performed with the laser beam (3', 13, 23, 33, 43, 53) aligned at a constant angle α relative to the workpiece (1, 11, 21, 31, 41, 55).

11. The method according to any one of claims 1 to 9, characterized in that When removing material from the workpiece (1, 11, 21, 31, 41, 55), the angle α varies within an angle range of 1≤α≤10°.

12. The method according to any one of the preceding claims, characterized in that The laser beam (3', 13, 23, 33, 43, 53) moves relative to the surface of the workpiece (1, 11, 21, 31, 41, 55), wherein during the relative movement, the angle α between the axis of the laser beam and the tangent of the surface of the workpiece to be processed is within an angle range of 1≤α≤10°, and the relative movement is a superposition of a first movement and a second movement, wherein during the first movement, the laser beam (3', 13, 23, 33, 43, 53) moves between a first point A on the surface of the workpiece (1, 11, 21, 31, 41, 55) and a second point B on the surface of the workpiece (1, 11, 21, 31, 41, 55), wherein during the second movement, the laser beam (3', 13, 23, 33, 43, 53) moves within a closed or open curve, wherein the range of the curve is smaller than the path of the laser beam (3', 13, 23, 33, 43, 53) from point A to point B.

Images