Laser beam machine

Abstract

To provide a laser beam machine that can suppress heat generation of a galvanometer mirror and vibrate the galvanometer mirror at high frequency.SOLUTION: A first galvanometer mirror 32a has a reflective coating applied to a first incident plane on which a laser beam is incident, and reflects the laser beam incident on the first incident plane. A second galvanometer mirror 32b has a reflective coating applied to a second incident plane on which the laser beam is incident, and reflects the laser beam incident on the second incident plane. The first galvanometer mirror 32a and the second galvanometer mirror 32b are formed of a glass material that transmits a portion of the laser beam that is incident on the first and second incident planes and is not reflected by the reflective coating but is transmitted through the reflective coating and penetrates into an interior. A first damper 41 and a second damper 42 absorb the laser beam transmitted through the first galvanometer mirror 32a and the second galvanometer mirror 32b.SELECTED DRAWING: Figure 15

Description

[Technical field]

[0001] The present invention relates to a laser processing machine. [Background technology]

[0002] Patent Documents 1 to 3 describe laser processing machines that process a workpiece by vibrating a laser beam emitted from a processing head using a galvanometer mirror of a galvanometer scanner unit. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5388948 [Patent Document 2] Patent No. 6272587 [Patent Document 3] Patent No. 6748150 Summary of the Invention [Problem to be solved by the invention]

[0004] In order to make the laser beam oscillate at a high frequency, the galvanometer mirror is generally made of silicon (Si) or silicon carbide (SiC), which can increase its rigidity. The surface of the galvanometer mirror is coated with a reflective coating to reflect the incident laser beam. In recent years, the laser beam emitted by a laser oscillator has become higher in power. Even if the reflectivity of the laser beam due to the reflective coating is, for example, 99.9%, the light absorption rate of silicon or silicon carbide is almost 100%, so the galvanometer mirror will generate heat due to the high-power laser beam that is not reflected by the reflective coating and passes through it. If the galvanometer mirror is made larger, the heat generation of the galvanometer mirror can be reduced.

[0005] On the other hand, there is a demand for the vibration frequency of the galvanometer mirror to be high, at 1 kHz or more. Increasing the size of the galvanometer mirror increases the inertia, making it difficult to vibrate the galvanometer mirror at the required high frequency. Therefore, there is a demand for a laser processing machine that can suppress heat generation in the galvanometer mirror and vibrate the galvanometer mirror at a high frequency. [Means for solving the problem]

[0006] One aspect of one or more embodiments includes a processing head including a collimation lens that converts a diverging laser beam into collimated light, a galvanometer scanner unit that receives the laser beam emitted from the collimation lens and vibrates the laser beam to be irradiated onto a workpiece to be processed, and a focusing lens that focuses the laser beam emitted from the galvanometer scanner unit and irradiates the workpiece, the galvanometer scanner unit having a first incident plane on which the laser beam is incident and a first galvanometer mirror that reflects the laser beam incident on the first incident plane, and a focusing lens that rotates the first galvanometer mirror. a second galvanometer motor that drives a first galvanometer mirror, a second incident plane on which a laser beam is incident is provided with a reflective coating, a second galvanometer mirror that reflects the laser beam incident on the second incident plane, and a second galvanometer motor that drives to rotate the second galvanometer mirror, the first and second galvanometer mirrors being formed of a glass material that transmits a laser beam that is not reflected by the reflective coating and that has penetrated the reflective coating and entered inside, of the laser beam that is incident on the first and second incident planes, respectively, and the laser processing machine is further provided with first and second dampers that absorb the laser beam that has transmitted through the first and second galvanometer mirrors. Effect of the Invention

[0007] According to the laser processing machine of one or more embodiments, heat generation in the galvanometer mirror can be suppressed, and the galvanometer mirror can be vibrated at a high frequency. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram illustrating a laser processing machine according to one or more embodiments. [Diagram 2] FIG. 2 is a perspective view showing a galvano scanner unit included in the laser processing machine according to one or more embodiments. [Diagram 3] FIG. 3 is a perspective view of the galvanometer mirror of the first configuration example as seen from behind. [Figure 4] FIG. 4 is a front view of the galvanometer mirror of the first configuration example. [Diagram 5] FIG. 5 is a rear view of the galvanometer mirror of the first configuration example. [Figure 6A] FIG. 6A is a plan view showing the chamfering of four corners for forming a galvano mirror of the first configuration example from a rectangular sapphire glass plate. [Figure 6B] FIG. 6B is a side view showing partial thickness chamfering for forming the galvanometer mirror of the first configuration example from a rectangular sapphire glass plate. [Figure 7] FIG. 7 is a perspective view showing a mounting structure of a galvanometer mirror to a shaft of a galvanometer motor in the first configuration example. [Figure 8] FIG. 8 is a perspective view of the galvanometer mirror of the second configuration example as seen from behind. [Figure 9] FIG. 9 is a front view of the galvanometer mirror of the second configuration example. [Figure 10] FIG. 10 is a rear view of the galvanometer mirror of the second configuration example. [Figure 11] FIG. 11 is a side view showing partial thickness chamfering for forming a galvanometer mirror of the second configuration example from a rectangular parallelepiped synthetic quartz plate. [Figure 12] FIG. 12 is a perspective view of a galvanometer mirror according to a modification of the second configuration example, as viewed from behind. [Figure 13] FIG. 13 is a front view of a modified galvanometer mirror according to the second configuration example. [Figure 14] FIG. 14 is a rear view of a modified example of the galvanometer mirror of the second configuration example. [Figure 15] FIG. 15 is a cross-sectional view showing a detailed configuration example of the collimator unit included in the laser processing machine according to the first embodiment. [Figure 16] FIG. 16 is a cross-sectional view showing a detailed configuration example of a collimator unit included in the laser processing machine according to the second embodiment. [Figure 17] FIG. 17 is a top view showing a detailed configuration example of a collimator unit included in the laser processing machine according to the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, a laser processing machine according to one or more embodiments will be described with reference to the accompanying drawings. First, an example of the overall configuration of a laser processing machine according to one or more embodiments will be described. In FIG. 1, a laser processing machine 100 includes a laser oscillator 10, a process fiber 12, a laser processing unit 20, an NC device 50, and an assist gas supply device 80.

[0010] The laser oscillator 10 generates and emits a laser beam, and the process fiber 12 transmits the laser beam emitted from the laser oscillator 10 to the laser processing unit 20. Typically, the laser oscillator 10 is a fiber laser oscillator that emits a laser beam with a wavelength of 1060 nm to 1080 nm. The laser oscillator 10 is not limited to a fiber laser oscillator. The NC device 50 is an example of a control device that controls each part of the laser processing machine 100.

[0011] The laser processing unit 20 has a processing table 21 on which the sheet metal W, which is the workpiece to be processed, is placed, a gate-shaped X-axis carriage 22, a Y-axis carriage 23, a collimator unit 30 fixed to the Y-axis carriage 23, and a processing head 35. The X-axis carriage 22 is configured to be movable in the X-axis direction on the processing table 21. The Y-axis carriage 23 is configured to be movable in the Y-axis direction perpendicular to the X-axis on the X-axis carriage 22. The X-axis carriage 22 and the Y-axis carriage 23 function as a moving mechanism that moves the processing head 35 along the surface of the sheet metal W in the X-axis direction, the Y-axis direction, or any composite direction of the X-axis direction and the Y-axis direction.

[0012] Instead of moving the processing head 35 along the surface of the metal sheet W, the processing head 35 may be configured to be fixed in position and the metal sheet W may be moved. The laser processing machine 100 may be provided with a movement mechanism that moves the processing head 35 relative to the surface of the metal sheet W.

[0013] A nozzle 36 having a circular opening 36a at its tip and emitting a laser beam from the opening 36a is attached to the processing head 35. The laser beam emitted from the opening 36a of the nozzle 36 is irradiated onto the metal sheet W. An assist gas supply device 80 supplies nitrogen, oxygen, or the like as an assist gas to the processing head 35. When the metal sheet W is processed, the assist gas is sprayed onto the metal sheet W from the opening 36a.

[0014] 2, the collimator unit 30 includes a collimation lens 301, a galvanometer scanner unit 302, and a bend mirror 303. The collimation lens 301 converts the divergent laser beam emitted from the process fiber 12 into parallel light (collimated light). The galvanometer scanner unit 302 includes a galvanometer motor 33a (first galvanometer motor) and a galvanometer motor 33b (second galvanometer motor) that drive the galvanometer mirror 32a (first galvanometer mirror) and the galvanometer mirror 32b (second galvanometer mirror) to rotate them within a predetermined angle range, respectively.

[0015] The collimated laser beam emitted from the collimation lens 301 is incident on the galvanometer mirror 32a, which reflects the incident laser beam. The laser beam reflected by the galvanometer mirror 32a is incident on the galvanometer mirror 32b, which reflects the incident laser beam. The laser beam reflected by the galvanometer mirror 32b is incident on the bend mirror 303. The bend mirror 303 reflects the laser beam emitted from the galvanometer scanner unit 302 downward in the Z-axis direction, which is perpendicular to the X-axis and Y-axis.

[0016] 2, the galvanometer motors 33a and 33b are fixed to a support member (not shown), and the positions of the galvanometer mirrors 32a and 32b are set in the space of the collimator unit 30. The galvanometer mirrors 32a and 32b may be collectively referred to as the galvanometer mirror 32, and the galvanometer motors 33a and 33b may be collectively referred to as the galvanometer motor 33. A detailed configuration of the collimator unit 30 will be described later.

[0017] The processing head 35 is provided with a focusing lens 304 that focuses the laser beam reflected by the bend mirror 303 and irradiates the metal sheet W with the laser beam.

[0018] The laser processing machine 100 is centered so that the laser beam emitted from the opening 36a of the nozzle 36 is located at the center of the opening 36a. In a standard state, the laser beam is emitted from the center of the opening 36a. The galvanometer scanner unit 302 functions as a beam vibration mechanism that vibrates the laser beam, which travels through the processing head 35 and is emitted from the opening 36a, within the opening 36a. The NC device 50 controls the galvanometer motor 33a to rotate the galvanometer mirror 32a, and controls the galvanometer motor 33b to rotate the galvanometer mirror 32b.

[0019] The galvano scanner unit 302 can displace the laser beam irradiated to the metal sheet W in the X-axis direction, the Y-axis direction, or any composite direction of the X-axis direction and the Y-axis direction under the control of the NC device 50. This allows the galvano scanner unit 302 to vibrate the laser beam in a direction parallel to the traveling direction of the processing head 35 (laser beam), in a direction perpendicular to the traveling direction, or so that the beam spot draws a circle.

[0020] Next, a detailed description will be given of a configuration example of the galvanometer mirror 32. In a first configuration example of the galvanometer mirror 32, the galvanometer mirror 32 is formed using sapphire glass as the glass material. The galvanometer mirror 32 formed using sapphire glass in the first configuration example will be referred to as the galvanometer mirror 32S. In a second configuration example of the galvanometer mirror 32, the galvanometer mirror 32 is formed using synthetic quartz as the glass material. The galvanometer mirror 32 formed using synthetic quartz in the second configuration example will be referred to as the galvanometer mirror 32Q (or 32Q'). As the galvanometer mirrors 32a and 32b in FIG. 2, any one of the galvanometer mirrors 32S, 32Q, and 32Q' is used. The galvanometer mirrors 32S, 32Q, and 32Q' will be described in detail in order.

[0021] <First configuration example> 3 to 5 are respectively a perspective view, a front view, and a rear view of the galvanometer mirror 32S as seen from the rear. Sapphire glass is formed by artificially crystallizing high-purity aluminum oxide to a large size. The galvanometer mirror 32S is shaped as shown in Figs. 3 to 5 by chamfering multiple faces of a rectangular sapphire glass plate, as described later.

[0022] 3 to 5, a laser beam is incident on the incident plane S11. The incident plane S11 is provided with a reflective coating made of a dielectric multilayer film that reflects a laser beam in a predetermined wavelength band. The incident plane S11 has a reflectance of 99.5% or more for a laser beam with a wavelength of 1040 nm to 1150 nm. Therefore, the incident plane S11 reflects 99.5% or more of the incident laser beam.

[0023] As described later, the lower end of the galvanometer mirror 32S in Fig. 3 is an end that is connected to the tip of a shaft 331 (see Fig. 7) of the galvanometer motor 33. A first end face 321 located on the lower end side is connected to the incident plane S11. A second end face 322 located on the opposite side to the first end face 321 along the direction of the shaft 331 is also connected to the incident plane S11. The direction connecting the first end face 321 and the second end face 322 is defined as the length direction.

[0024] As shown in FIG. 4, the length from the first end face 321 to the second end face 322 is L32. The widest part 32WP is the part that is widest in the width direction perpendicular to the length direction. The width of the widest part 32WP is W32. The length L32 and the width W32 have a relationship of L32>W32. As an example, the length L32 is about 33 mm, and the width W32 is about 22 mm. The widest part 32WP is located on the second end face 322 side of the center of the length L32 of the galvanometer mirror 32S. The entire range of the widest part 32WP in the length direction is located on the second end face 322 side of the center of the length L32.

[0025] 3 to 5, the first side end face 323 and the second side end face 324 respectively connect both ends in the width direction of the first end face 321 and both ends in the width direction of the widest part 32WP. The first side end face 323 and the second side end face 324 are spaced apart in the width direction from the first end face 321 toward the widest part 32WP. The third side end face 325 and the fourth side end face 326 respectively connect both ends in the width direction of the second end face 322 and both ends in the width direction of the widest part 32WP. The third side end face 325 and the fourth side end face 326 are spaced apart in the width direction from the second end face 322 toward the widest part 32WP.

[0026] The galvanometer mirror 32S has a thickest portion 327 at its center in the width direction. As an example, the thickness of the thickest portion 327 is 3 mm. In the galvanometer mirror 32S, the thickest portion 327 is formed over the entire range from the first end face 321 to the second end face 322. The surface of the thickest portion 327 is a flat surface S12. The first side portion 328 and the second side portion 329 are provided on both sides of the thickest portion 327 in the width direction. The first side portion 328 and the second side portion 329 have a thinner thickness from the thickest portion 327 toward both ends in the width direction. The surfaces of the first side portion 328 and the second side portion 329 are flat surfaces S13 and S14, respectively.

[0027] The galvanometer mirror 32S having the above-mentioned shape can be formed by chamfering the four hatched corners C1 to C4 of a rectangular sapphire glass plate 320S, as shown in FIG. 6A, and by chamfering the hatched regions T1 and T2 of the sapphire glass plate 320S in the thickness direction, as shown in FIG. 6B.

[0028] Of the laser beams incident on the incident plane S11, a small portion that is not reflected by the reflective coating passes through the reflective coating and enters the inside of the galvanometer mirror 32S. Since the light absorption rate of sapphire glass, which is the glass material forming the galvanometer mirror 32S, is less than 1%, the galvanometer mirror 32S transmits more than 99% of the laser beam that has entered the inside. Therefore, the galvanometer mirror 32S hardly generates heat due to the laser beam that passes through without being reflected by the reflective coating. Therefore, since heat generation is suppressed even if the beam diameter of the collimated light emitted from the collimation lens 301 is narrowed, there is no need to enlarge the galvanometer mirror 32S, and it can be made as small as possible.

[0029] The flat surfaces S12 to S14 are preferably coated with an anti-reflection coating made of a dielectric multilayer film. The flat surfaces S12 to S14 on which the anti-reflection coating is applied have a transmittance of 98% or more for a laser beam having a wavelength of 1040 nm to 1150 nm.

[0030] 7, a fixing part 332 for fixing an end part of the galvanometer mirror 32S on the first end face 321 side is provided at the tip part of the shaft 331 of the galvanometer motor 33. The end part of the galvanometer mirror 32S on the first end face 321 side is inserted between a pair of protruding walls of the fixing part 332 and is fixed to the fixing part 332 by being bonded with an adhesive. In this way, the galvanometer mirror 32S is connected to the shaft 331 of the galvanometer motor 33, and the galvanometer mirror 32S rotates integrally with the shaft 331 due to the rotation of the shaft 331.

[0031] According to the galvanometer mirror 32S, the inertia can be significantly reduced compared to the inertia of the rectangular parallelepiped sapphire glass plate 320S by chamfering the four corners C1 to C4 and the thickness direction of the regions T1 and T2. According to the galvanometer mirror 32S, the heat generation can be suppressed, so the galvanometer mirror 32S can be made smaller, and the inertia can be reduced along with the miniaturization. Therefore, if the galvanometer mirror 32S is used as the galvanometer mirror 32 in the laser processing machine 100, the galvanometer mirror 32 can be vibrated at a high frequency. Here, the high frequency is, for example, 1 kHz or more.

[0032] Incidentally, when the galvanometer mirror 32S is rotated by the galvanometer motor 33 within a predetermined angle range, if the galvanometer mirror 32S is deformed by the vibration of the galvanometer mirror 32S, the beam profile of the laser beam emitted from the galvanometer mirror 32S deteriorates. If the beam profile of the laser beam deteriorates, the luminance of the laser beam on the surface of the sheet metal W decreases. The luminance of the laser beam on the surface of the sheet metal W is set to 100% when the laser beam emitted from the galvanometer mirror 32S is irradiated onto the sheet metal W in a state in which the galvanometer motor 33 does not drive the galvanometer mirror 32S. It is preferable that the thickness of the thickest part 327 is set to a thickness such that at least 98% of the luminance is obtained when the laser beam emitted from the galvanometer mirror 32S is irradiated onto the sheet metal W in a state in which the galvanometer motor 33 drives the galvanometer mirror 32S and the galvanometer mirror 32S is deformed.

[0033] Galvanometer mirror 32S has a shape in which four corners C1 to C4 and regions T1 and T2 in the thickness direction are chamfered, and is therefore more easily deformed than rectangular sapphire glass plate 320S. If the thickness of thickest part 327 is set to a thickness that can obtain the maximum brightness of the laser beam of 98% or more as described above, deformation of galvanometer mirror 32S does not substantially pose a problem.

[0034] <Second configuration example> 8 to 10 are respectively a perspective view, a front view, and a rear view of the galvanometer mirror 32Q as seen from the rear. The galvanometer mirror 32Q is shaped as shown in Figs. 8 to 10 by chamfering a plurality of faces of a rectangular parallelepiped synthetic quartz plate, as will be described later. In the second configuration example, the same reference numerals are used for parts that are substantially the same as those in the first configuration example, and their description may be omitted.

[0035] 8 to 10, a laser beam is incident on the incident plane S21. The incident plane S21 is provided with a reflective coating made of a dielectric multilayer film that reflects a laser beam in a predetermined wavelength band. The incident plane S21 has a reflectance of 99.5% or more for a laser beam with a wavelength of 1040 nm to 1150 nm. Therefore, the incident plane S21 reflects 99.5% or more of the incident laser beam. The first end face 321 and the second end face 322 are connected to the incident plane S21.

[0036] 9, the length from the first end face 321 to the second end face 322 is L32, and the width of the widest part 32WP is W32. As with the galvanometer mirror 32S, the length L32 and the width W32 have a relationship of L32>W32. As an example, the length L32 is about 33 mm, and the width W32 is about 22 mm. The widest part 32WP is located closer to the second end face 322 than the center of the length L32 of the galvanometer mirror 32Q.

[0037] 8 to 10, the first side end face 323 and the second side end face 324 respectively connect both ends in the width direction of the first end face 321 and both ends in the width direction of the widest part 32WP. The first side end face 323 and the second side end face 324 are spaced apart in the width direction from the first end face 321 toward the widest part 32WP. The third side end face 325 and the fourth side end face 326 respectively connect both ends in the width direction of the second end face 322 and both ends in the width direction of the widest part 32WP. The third side end face 325 and the fourth side end face 326 are spaced apart in the width direction from the second end face 322 toward the widest part 32WP.

[0038] The galvanometer mirror 32Q has a thickest portion 327 at its center in the width direction. As an example, the thickness of the thickest portion 327 is about 4.4 mm. In the galvanometer mirror 32Q, the thickest portion 327 is not formed over the entire range from the first end face 321 to the second end face 322, but is formed over the range from the first end face 321 to the widest portion 32WP within the range from the first end face 321 to the second end face 322. The end of the thickest portion 327 on the second end face 322 side is located at a predetermined position in the length direction of the widest portion 32WP. The surface of the thickest portion 327 is a flat surface S22.

[0039] The first side portion 328 and the second side portion 329 are provided on both sides in the width direction of the thickest portion 327. The thicknesses of the first side portion 328 and the second side portion 329 become thinner from the thickest portion 327 toward both ends in the width direction. The surfaces of the first side portion 328 and the second side portion 329 are planes S23 and S24, respectively.

[0040] Galvano mirror 32Q has inclined tip 330 formed on the second end face 322 side. Inclined tip 330, the thickness decreases from the end of thickest part 327 on the second end face 322 side toward second end face 322. The surface of inclined tip 330 forms plane S25.

[0041] The galvanometer mirror 32Q having the above-mentioned shape can be formed by chamfering the rectangular parallelepiped synthetic quartz plate 320Q shown in Fig. 11 in the same manner as the sapphire glass plate 320S shown in Fig. 6A and Fig. 6B, and further chamfering the hatched region T3 in the thickness direction. That is, the galvanometer mirror 32Q can be formed by chamfering the four corners C1 to C4 and the regions T1 to T3 in the thickness direction of the rectangular parallelepiped synthetic quartz plate 320Q.

[0042] Of the laser beams incident on the incident plane S21, a small portion that is not reflected by the reflective coating passes through the reflective coating and enters the inside of the galvanometer mirror 32Q. Since the optical absorption rate of synthetic quartz, which is the glass material forming the galvanometer mirror 32Q, is nearly 0%, the galvanometer mirror 32Q transmits nearly 100% of the laser beam that enters the inside. Therefore, the galvanometer mirror 32Q generates almost no heat due to the laser beam that passes through without being reflected by the reflective coating. Therefore, there is no need to enlarge the galvanometer mirror 32Q, and a minimum size is sufficient.

[0043] The flat surfaces S22 to S25 are preferably coated with an anti-reflection coating made of a dielectric multilayer film. The flat surfaces S22 to S25 on which the anti-reflection coating is applied have a transmittance of 98% or more for a laser beam having a wavelength of 1040 nm to 1150 nm.

[0044] The attachment structure of galvanometer mirror 32Q to shaft 331 of galvanometer motor 33 is the same as the attachment structure of galvanometer mirror 32S to shaft 331 of galvanometer motor 33 shown in Fig. 7. Galvanometer mirror 32Q is fixed to fixed portion 332 by inserting an end portion on the first end face 321 side between a pair of protruding walls of fixed portion 332 and adhering with an adhesive. Galvanometer mirror 32Q is connected to shaft 331 of galvanometer motor 33, and galvanometer mirror 32Q rotates integrally with shaft 331 as shaft 331 rotates.

[0045] According to the galvanometer mirror 32Q, the inertia can be significantly reduced compared to the inertia of the rectangular parallelepiped synthetic quartz plate 320Q by chamfering the four corners C1 to C4 and the thickness direction of the regions T1 to T3. According to the galvanometer mirror 32Q, the heat generation can be suppressed, so the galvanometer mirror 32Q can be made smaller, and the inertia can be reduced along with the miniaturization. Therefore, if the galvanometer mirror 32Q is used as the galvanometer mirror 32 in the laser processing machine 100, the galvanometer mirror 32 can be vibrated at a high frequency. Here, the high frequency is, for example, 1 kHz or more.

[0046] In the case of the galvanometer mirror 32Q as well, the brightness of the laser beam on the surface of the metal sheet W is set to 100% when the laser beam emitted from the galvanometer mirror 32Q is irradiated onto the metal sheet W while the galvanometer motor 33 is not driving the galvanometer mirror 32Q. It is preferable that the thickness of the thickest part 327 is set to such a thickness that a brightness of at least 98% is obtained when the laser beam emitted from the galvanometer mirror 32Q is irradiated onto the metal sheet W while the galvanometer motor 33 drives the galvanometer mirror 32Q and the galvanometer mirror 32Q is deformed.

[0047] The reason why the galvanometer mirror 32Q, whose glass material is synthetic quartz, has the inclined tip 330, which is chamfered in the thickness direction in the region T3, is as follows. When the galvanometer mirror 32 is vibrated, the galvanometer mirror 32Q, whose glass material is synthetic quartz, is more likely to deform than the galvanometer mirror 32S, whose glass material is sapphire glass. Therefore, there are cases where the thickness of the thickest part 327 of the galvanometer mirror 32Q needs to be made thicker than that of the galvanometer mirror 32S. When the thickness of the thickest part 327 of the galvanometer mirror 32Q is made thicker than that of the thickest part 327 of the galvanometer mirror 32S, it is preferable to provide the inclined tip 330 in order to reduce the inertia.

[0048] <Modification of the second configuration example> Figures 12 to 14 show galvanometer mirror 32Q', which is a modified example of galvanometer mirror 32Q. Figures 12 to 14 are a perspective view, a front view, and a rear view, respectively, of galvanometer mirror 32Q' as seen from the rear. In galvanometer mirror 32Q', parts that are substantially the same as those in galvanometer mirror 32Q are denoted by the same reference numerals, and descriptions thereof may be omitted.

[0049] As shown in FIG. 12 and FIG. 14, in the galvano mirror 32Q', the thickest part located at the center in the width direction is a trapezoidal thickest part 327'. The surface of the thickest part 327' is a trapezoidal flat surface S22'. As the rectangular thickest part 327 and flat surface S22 in the galvano mirror 32Q are changed to the trapezoidal thickest part 327' and flat surface S22', the first side part 328 and the second side part 329 are respectively a first side part 328' and a second side part 329', and the inclined tip part 330 is an inclined tip part 330'. The surfaces of the first side part 328' and the second side part 329' are respectively flat surfaces S23' and S24', and the surface of the inclined tip part 330' is a flat surface S25'.

[0050] The galvanometer mirror 32Q' having the above-mentioned shape can be formed by chamfering the four corners of the rectangular parallelepiped synthetic quartz plate 320Q in the same manner as the galvanometer mirror 32Q, and by chamfering a portion of the thickness to form a first side portion 328', a second side portion 329', and an inclined tip portion 330'. The attachment structure of the galvanometer mirror 32Q' to the shaft 331 of the galvanometer motor 33 is the same as the attachment structure of the galvanometer mirror 32Q to the shaft 331 of the galvanometer motor 33.

[0051] According to galvanometer mirror 32Q', when length L32, width W32, and thickness of thickest portion 327' are the same as length L32, width W32, and thickness of thickest portion 327 in galvanometer mirror 32Q, the inertia can be made smaller than that in galvanometer mirror 32Q.

[0052] Incidentally, the galvano mirror 32S whose glass material is sapphire glass does not have the inclined tip 330 that is chamfered in the thickness direction of the region T3, but the inclined tip 330 may be provided to further reduce the inertia. Also, the galvano mirror 32Q or 32Q' whose glass material is synthetic quartz may be configured without the inclined tip 330 or 330'.

[0053] Next, a detailed configuration example of the collimator unit 30 provided in the laser processing machine 100 will be described with reference to Fig. 15 to Fig. 17. Fig. 15 shows the collimator unit 30 provided in the laser processing machine 100 according to the first embodiment, and Figs. 16 and 17 show the collimator unit 30 provided in the laser processing machine according to the second embodiment. Figs. 15 to 17 show a case where the galvanometer mirror 32S is used as the galvanometer mirror 32.

[0054] First Embodiment In FIG. 15, the collimator unit 30 has a housing 30B fixed on a base 30C and a housing 30A connected to the housing 30B. The housings 30A, 30B, and the base 30C are made of metal such as aluminum or copper. The housing 30A connects the process fiber 12 and houses a collimation lens 301 at the end on the housing 30B side. The collimation lens 301 is attached to a collimation lens attachment portion 311. A cylindrical laser beam path 30A1 is formed in the housing 30A. The divergent laser beam emitted from the process fiber 12 passes through the laser beam path 30A1 and enters the collimation lens 301.

[0055] The housing 30B houses the galvano scanner unit 302. The housing 30B is formed with a laser beam path 30B1 along which a laser beam emerges from the collimation lens 301, enters the incident plane S11 (first incident plane) of the galvano mirror 32a, is reflected by the incident plane S11, and is reflected by the incident plane S11 (second incident plane) of the galvano mirror 32b. A galvano motor 33a is attached to the upper part of the housing 30B by a motor holder 33h, and the galvano mirror 32a is located within the laser beam path 30B1. A galvano motor 33b is attached to the side of the housing 30B by a motor holder 33h, and the galvano mirror 32b is located within the laser beam path 30B1.

[0056] The laser beam traveling path 30B1 is connected to a first transmitted light traveling path 30B2 which causes the laser beam transmitted through the galvanometer mirror 32a to travel toward the outside of the housing 30B, and a second transmitted light traveling path 30B3 which causes the laser beam transmitted through the galvanometer mirror 32b to travel toward the outside of the housing 30B.

[0057] A first damper 41 is attached to the outer surface of the housing 30B so as to close the end of the first transmitted light path 30B2, and a second damper 42 is attached to the outer surface of the housing 30B so as to close the end of the second transmitted light path 30B3. The first damper 41 and the second damper 42 can be formed by black plating an aluminum or copper metal plate. For example, black Ni plating or black Cr plating can be used as the black plating. The first damper 41 and the second damper 42 preferably have an absorptivity of 70% or more in the wavelength band of the laser beam.

[0058] The first damper 41 absorbs the laser beam transmitted through the galvanometer mirror 32a and converts it into heat. The second damper 42 absorbs the laser beam transmitted through the galvanometer mirror 32b and converts it into heat. The first damper 41 and the second damper 42 are respectively attached with a first heat sink 43 and a second heat sink 44 via a heat dissipation sheet or a heat dissipation gel. The first heat sink 43 and the second heat sink 44 are in contact with or in close proximity to the first damper 41 and the second damper 42, respectively. The first heat sink 43 and the second heat sink 44 dissipate the heat generated in the first damper 41 and the second damper 42, respectively.

[0059] The first damper 41 and the first heat sink 43 may be integrated, and the second damper 42 and the second heat sink 44 may be integrated. That is, the collimator unit 30 includes the first heat sink 43 and the second heat sink 44 which are separate from or integrated with the first damper 41 and the second damper 42, respectively.

[0060] The bend mirror 303 is attached to a bend mirror mounting plate 313, which is fixed to the housing 30B. The focusing lens 304 is attached to a focusing lens mounting portion 314.

[0061] 15, the galvanometer mirror 32 is made of a glass material that transmits the laser beam that has penetrated the reflective coating and entered the interior, so it is possible to suppress heat generation from the galvanometer mirror 32. The laser beam that has transmitted through the galvanometer mirror 32 is absorbed by the first damper 41 and the second damper 42, and the first damper 41 and the second damper 42 are air-cooled by the first heat sink 43 and the second heat sink 44, so heat generation by the laser beam that has transmitted through the galvanometer mirror 32 does not become a problem.

[0062] Since heat generation from the galvanometer mirror 32 can be suppressed, it is possible to reduce the size of the galvanometer mirror 32. Therefore, the laser processing machine 100 can vibrate the galvanometer mirror 32 at a high frequency.

[0063] <Second embodiment> In Fig. 16 and Fig. 17, the same parts as in Fig. 15 are given the same reference numerals, and their explanation may be omitted. In Fig. 16, a laser beam path 30B4 is formed in the housing 30B, instead of the laser beam path 30B1, the first transmitted light path 30B2, and the second transmitted light path 30B3. The galvanometer mirrors 32a and 32b are located in the laser beam path 30B4.

[0064] The laser beam traveling path 30B4 has a first terminal end face B41 at a position a predetermined distance away from the galvanometer mirror 32a on the planes S12-S14 side of the galvanometer mirror 32a. The first terminal end face B41 prevents the laser beam from traveling through the galvanometer mirror 32a. The laser beam traveling path 30B4 has a second terminal end face B42 at a position a predetermined distance away from the galvanometer mirror 32b on the planes S12-S14 side of the galvanometer mirror 32b. The second terminal end face B42 prevents the laser beam from traveling through the galvanometer mirror 32b.

[0065] At least the first end face B41 and the second end face B42 are black plated. As in the first embodiment, black Ni plating or black Cr plating can be used as the black plating. By black plating the first end face B41 and the second end face B42, the first end face B41 and the second end face B42 function as first and second dampers that absorb the laser beam. The first end face B41 and the second end face B42 preferably have an absorptance of 70% or more in the wavelength band of the laser beam. Note that since it is not easy to black plate only the first end face B41 and the second end face B42, the entire housing 30B may be black plated.

[0066] As shown in Fig. 17, a water passage 45 for cooling the first end face B41 and the second end face B42 is provided in the vicinity of the first end face B41 and the second end face B42 of the housing 30B. Tubes 46a and 46b through which cooling water flows are connected to the water passage 45 by pipe joints 47a and 47b, respectively. The cooling water flows from a tube (e.g., tube 46a) on one side of the housing 30B through the water passage 45 to a tube (e.g., tube 46b) on the other side.

[0067] 16 and 17, the galvanometer mirror 32 is made of a glass material that transmits the laser beam that has penetrated the reflective coating and entered the interior, so that heat generation in the galvanometer mirror 32 can be suppressed. The laser beam that has transmitted through the galvanometer mirror 32 is absorbed by the first end face B41 and the second end face B42 that function as the first and second dampers. The first end face B41 and the second end face B42 are water-cooled by the cooling water flowing through the water passage 45, so heat generation by the laser beam that has transmitted through the galvanometer mirror 32 does not become a problem.

[0068] 16 and 17, it is possible to suppress heat generation from the galvanometer mirror 32, and therefore to reduce the size of the galvanometer mirror 32. Therefore, the laser processing machine 100 can vibrate the galvanometer mirror 32 at a high frequency.

[0069] The present invention is not limited to one or more of the embodiments described above, and various modifications can be made without departing from the gist of the present invention. [Explanation of symbols]

[0070] 10 Laser Oscillator 12 Process Fiber 20 Laser Processing Unit 21 Processing table 22 X-axis carriage 23 Y-axis carriage 30 Collimator unit 30A, 30B housing 30C Base 35 Processing head 32a, 32b, 32Q, 32Q', 32S Galvanometer Mirror 32WP widest part 33a, 33b Galvano motor 36 Nozzles 36a aperture 41 First damper 41 42 Second Damper 43 First Heat Sink 44 Second Heat Sink 45 Waterway 46a, 46b tube 47a, 47b Pipe joint 50 NC device 80 Assist gas supply device 100 Laser processing machine 301 Collimation Lens 302 Galvano Scanner Unit 303 Bend Mirror 304 Focusing Lens 321 First end face 322 Second End Face 323 First side end surface 324 Second side end face 325 Third side end face 326 Fourth side end face 327,327' Thickest part 328,328' First side 329,329' Second side 330,330' Beveled tip S11,S21 Incident plane S12~S14,S22~S25,S22'~S25' plane W Sheet metal (work material)

Claims

1. a collimation lens for converting a diverging laser beam into a collimated beam; a galvano scanner unit into which the laser beam emitted from the collimation lens is incident and which vibrates the laser beam to be irradiated onto a workpiece to be processed; a processing head having a focusing lens for focusing the laser beam emitted from the galvano scanner unit and irradiating the laser beam onto the workpiece; Equipped with The galvano scanner unit includes: a first galvanometer mirror having a first incident plane on which a laser beam is incident and having a reflective coating applied thereto, the first galvanometer mirror reflecting the laser beam incident on the first incident plane; a first galvanometer motor that drives the first galvanometer mirror to rotate; a second galvanometer mirror having a second incident plane on which the laser beam is incident and having a reflective coating applied thereto, the second galvanometer mirror reflecting the laser beam incident on the second incident plane; a second galvanometer motor that drives the second galvanometer mirror to rotate; having the first and second galvanometer mirrors are formed of a glass material that transmits a laser beam that is incident on the first and second incident planes and is not reflected by the reflective coating but penetrates the reflective coating to enter inside the mirror, The laser beam is transmitted through the first and second galvanometer mirrors. Laser processing machine.

2. The housing for accommodating the galvano scanner unit includes: a laser beam traveling path for traveling a laser beam that exits the collimation lens, enters the first incident plane, is reflected by the first incident plane, enters the second incident plane, and is reflected by the second incident plane; first and second transmitted light paths connected to the laser beam path, for transmitting the laser beam transmitted through the first and second galvanometer mirrors toward the outside of the housing; is formed, The first and second dampers are attached to the outer surface of the housing so as to close the terminal ends of the first and second transmitted light paths, respectively.

2. The laser processing machine according to claim 1.

3. 3. The laser processing machine according to claim 2, further comprising first and second heat sinks which are separate from or integral with the first and second dampers, respectively.

4. A housing that houses the galvano scanner unit has a laser beam traveling path along which a laser beam travels, the laser beam being emitted from the collimation lens, incident on the first incident plane, reflected by the first incident plane, incident on the second incident plane, and reflected by the second incident plane; the laser beam path has first and second end faces that impede the propagation of the laser beam transmitted through the first and second galvanometer mirrors, respectively; At least the first and second end faces are black-plated, so that the first and second end faces function as the first and second dampers.

2. The laser processing machine according to claim 1.

5. 5. The laser processing machine according to claim 4, wherein the housing has water passages near the first and second end faces for cooling the first and second end faces.

Images