Laser oscillator and laser processing apparatus including the same

Abstract

To provide a laser oscillator capable of collecting an air flow from a flow passage connected to a laser light source without stopping the laser light source.SOLUTION: The laser oscillator 80 comprises a laser beam source 10, a pump 41, a first filter 42 for removing organic matter, a main pipe 44, a bypass pipe 44A, a collecting pipe 46, a flow control valve 45A, and first and second valves 45B and 45C. The main pipe 44 is connected in series to the laser light source 10, the pump 41, and the first filter 42, and dry air is circulated inside the main pipe 44. The bypass pipe 44A is connected in parallel with the main pipe 44, and the collecting pipe 46 is arranged in series with the bypass pipe 44A. The flow control valve 45A is arranged in series in the main pipe 44, and the first and second valves 45B and 45C are arranged in series in the bypass pipe 44A.SELECTED DRAWING: Figure 2B

Description

[Technical Field]

[0001] The present disclosure relates to a laser oscillator and a laser processing device including the same. [Background technology]

[0002] In recent years, expectations for laser processing have been rising for various materials such as copper, gold, and resin. For example, in the automotive industry, there are demands for electrification, miniaturization, high rigidity, greater design freedom, and improved productivity, and expectations for laser processing are high. To achieve highly productive processing, a laser light source capable of generating high-efficiency, high-power laser light is required. A semiconductor laser element is known as a suitable laser light source for this requirement. In particular, to increase the output of laser light, a laser light source equipped with a laser diode bar having multiple emitters that emit laser light is useful. In a laser processing device using such a laser light source, a technology has been proposed in which a pump and a dehumidifier are connected in series to the housing via piping, and dry air is circulated through a path including the piping, in order to adjust the moisture content inside the housing that houses the laser diode bar (see, for example, Patent Document 1).

[0003] When a semiconductor laser element emits high-power laser light, contaminants may adhere to the light-emitting end face of the semiconductor laser element and accumulate as deposits. A typical contaminant is a siloxane compound with a Si-O-Si bond. When a siloxane compound in the atmosphere is irradiated with laser light, a photodecomposition reaction occurs, and the decomposed products adhere to the light-emitting end face and form deposits.

[0004] When the thickness of the deposits accumulated on the light-emitting end face increases, the output power and beam quality of the laser light decrease. Therefore, various configurations have been proposed to prevent siloxane-derived deposits from adhering to the light-emitting end face of a semiconductor laser element. For example, Patent Document 2 describes a method in which the inside of a housing that houses a semiconductor laser element is filled with an insulating liquid containing a surfactant, and the insulating liquid is circulated to wash away and remove siloxane compounds adhering to the light-emitting end face of the semiconductor laser element. This prevents deposits from accumulating on the light-emitting end face of the semiconductor laser element. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2020-177990 [Patent Document 2] Japanese Patent Publication No. 2020-155652 Summary of the Invention [Problem to be solved by the invention]

[0006] However, the techniques proposed so far have not been able to collect siloxane from a flow path connected to a laser light source without stopping the laser light source.

[0007] The present disclosure has been made in consideration of these points, and its purpose is to provide a laser oscillator that can collect airflow from a flow path connected to a laser light source without stopping the laser light source, and a laser processing device equipped with the same. [Means for solving the problem]

[0008] In order to achieve the above object, a laser oscillator according to the present disclosure includes at least a laser light source that emits laser light and an airflow circulation mechanism, the airflow circulation mechanism including at least a pump that circulates airflow inside the laser light source, a first filter that removes at least chemical substances contained in the airflow, a main pipe that is connected in series to the laser light source, the pump, and the first filter and serves as a flow path for the airflow, and an airflow collection mechanism provided between an air intake port of the pump and an airflow outlet port of the laser light source, the airflow collection mechanism having a first connection point and a second connection point to the main pipe. a bypass pipe connected in parallel to the main pipe at a connection point; a collection pipe arranged in series with the bypass pipe; a flow control valve arranged in series with the main pipe located between the first connection point and the second connection point; a first valve arranged in series with a portion of the bypass pipe that is provided to extend from the first connection point; and a second valve arranged in series with a portion of the bypass pipe that is provided to extend from the second connection point, wherein a portion of the air flow passing through the bypass pipe is collected by the collection pipe.

[0009] The laser processing device according to the present disclosure is characterized by comprising at least the laser oscillator and a laser processing head that receives processing laser light emitted from the laser oscillator and irradiates the light toward a workpiece. [Effects of the Invention]

[0010] According to the present disclosure, airflow can be collected from a flow path connected to a laser light source without shutting down the laser light source. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a schematic configuration diagram of a laser processing device according to an embodiment. [Figure 2A] FIG. 2 is a schematic diagram illustrating the configuration of a main part of a laser oscillator during normal operation. [Figure 2B] FIG. 2 is a schematic diagram illustrating the configuration of the main parts of the laser oscillator when collecting dry air. [Figure 3]FIG. 10 is a schematic configuration diagram of a main part of a laser oscillator according to a comparative example. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Note that the following description of the preferred embodiments is merely exemplary in nature and is not intended to limit the present disclosure, its applications, or its uses.

[0013] (Background to the invention) One possible method for measuring the siloxane concentration is to measure the siloxane concentration by collecting the airflow passing through the housing, as in the configuration disclosed in Patent Document 1. However, in this case, it is necessary to provide a joint for attaching and detaching the collection tube to the piping.

[0014] To collect the airflow in the piping, for example, the following procedure must be performed. First, the laser light source is stopped, and the collection tube is connected to the piping. Then, the laser light source is turned on again, and the pump is operated to collect the airflow in the piping. However, in this case, there is a risk that foreign matter or outside air may get mixed into the piping, which is the airflow path, and flow into the aforementioned housing. If foreign matter or contaminants contained in the outside air get mixed into the inside of the housing, they may adhere to the light-emitting end face of the semiconductor laser element, degrading the characteristics of the laser light.

[0015] Therefore, the following disclosure proposes a method that can collect airflow from a flow path connected to a laser light source without shutting down the laser light source.

[0016] (Embodiment) [Configuration of laser processing equipment and laser oscillator] FIG. 1 is a schematic diagram of a laser processing device according to an embodiment.

[0017] The laser processing apparatus 200 includes a laser oscillator 80, an optical fiber 90, and a laser head 100. The laser oscillator 80 also includes a plurality of laser light sources 10, a beam combiner 20, a focusing optical unit 30, an airflow circulation mechanism 40, a control unit 60, a power supply 70, and a fourth housing 50. The plurality of laser light sources 10, the beam combiner 20, and the focusing optical unit 30 are housed inside the fourth housing 50. A portion of the optical fiber 90 is also housed inside the fourth housing 50.

[0018] The laser light source 10 has laser diode bars 12 inside the first housing 11 (see FIG. 2). Each laser diode bar 12 has a plurality of emitters that emit laser light. In the example shown in FIG. 2, one laser diode bar 12 is housed inside the first housing 11, but this is not particularly limited. One laser diode bar 12 may be housed inside the first housing 11. Also, one or more laser diodes may be housed inside the first housing 11. One emitter is formed in the laser diode. In addition, when one laser light source 10 includes multiple emitters, laser light emitted from each emitter may be collected into a single laser light by a collecting optical system (not shown) arranged inside the first housing 11 and emitted to the outside of the first housing 11. In other words, the laser light source 10 has one or more semiconductor laser elements inside the first housing 11.

[0019] The beam combiner 20 has a plurality of optical components (not shown) inside the second housing 21, and combines the laser beams emitted from the plurality of laser light sources 10 into a single processing laser beam LB. Inside the beam combiner 20, the processing laser beam LB is shaped so that it fits within the effective focusing diameter of a focusing lens (not shown) provided in the focusing optical unit 30. It is preferable that the processing laser beam LB be shaped inside the beam combiner 20 into a shape suitable for laser processing, that is, so that it is circular on a plane perpendicular to the traveling direction.

[0020] The focusing optical unit 30 has at least a focusing lens (not shown) inside the third housing 31, and focuses the processing laser light LB emitted from the beam combiner 20 and optically couples it to the incident end of the optical fiber 90.

[0021] The airflow circulation mechanism 40 supplies dry air, the moisture content and siloxane compound concentration (hereinafter referred to as siloxane concentration), to each of the first to third housings 11, 21, and 31. The dry air that has flowed inside each housing is collected by the airflow circulation mechanism 40 and supplied again to the inside of each housing. The configuration and operation of the airflow circulation mechanism 40 will be described in detail later.

[0022] The control unit 60 has one or more central processing units (CPUs) and a storage unit (neither shown). The storage unit is configured with semiconductor memory such as a random access memory (RAM) or a read only memory (ROM). The storage unit may further include a hard disk drive (HDD), a solid state drive (SSD), or the like.

[0023] The control unit 60 controls the laser oscillation of each laser light source 10 by supplying control signals such as output voltage and on time to the power source 70. It is also possible to control the laser oscillation of each laser light source 10 individually. For example, the laser oscillation output, on time, etc. may be different for each laser light source 10. The control unit 60 also controls the operation of the pump 41 (see FIG. 2) of the airflow circulation mechanism 40.

[0024] For example, processing parameters during laser processing are simultaneously displayed on the display unit 61. The display unit 61 usually includes a display device such as a liquid crystal display or an organic EL display.

[0025] As described above, the power supply 70 supplies power for laser oscillation to each of the multiple laser light sources 10. The power supplied to each laser light source 10 may be different based on a command from the control unit 60. Furthermore, if the laser head 100 is held by a manipulator (not shown) and is movable, the power supply 70 may supply power to the manipulator. Note that power may be supplied to the manipulator from a separate power supply (not shown).

[0026] The optical fiber 90 has at least a core and a cladding (not shown). The core is provided at the axial center of the optical fiber 90 and functions as an optical waveguide that guides the processing laser light LB incident from the focusing optical unit 30 to the laser head 100. The cladding is provided so as to surround the outer periphery of the core and functions as an optical confinement layer that confines the processing laser light LB inside the core.

[0027] The laser head 100 irradiates the processing laser light LB transmitted through the optical fiber 90 toward the outside. For example, in the laser processing apparatus 200 shown in Fig. 1, the processing laser light LB is irradiated toward a workpiece W, which is an object to be processed and placed at a predetermined position. In this manner, the workpiece W is laser processed.

[0028] In this embodiment, four laser light sources 10 are mounted on the laser processing apparatus 200, but this is not particularly limited. The number of mounted laser light sources 10 can be changed as appropriate depending on the output specifications required for the laser processing apparatus 200 and the output specifications of each laser light source 10. For example, there may be one laser light source 10. In this case, the beam combiner 20 functions only as a beam shaper for the processing laser light LB.

[0029] According to the laser processing apparatus 200 of this embodiment, the workpiece W can be laser processed using a high-power processing laser beam LB. This allows, for example, drilling or cutting a thick plate of the workpiece W in a short time. Furthermore, by using the optical fiber 90, it becomes easy to guide the processing laser beam LB to the workpiece W located away from the laser oscillator 80. Furthermore, by providing the laser head 100 at the tip of the optical fiber 90, it becomes easy to irradiate the processing laser beam LB at a desired position on the workpiece W.

[0030] [Airflow circulation mechanism configuration] FIG. 2A is a schematic diagram of the main parts of the laser oscillator during normal operation. FIG. 2B is a schematic diagram of the main parts of the laser oscillator during dry air collection. For ease of explanation, FIGS. 2A and 2B and FIG. 3 shown later illustrate the flow of dry air with respect to the first housing 11 of the laser light source 10. Similarly, dry air is supplied to the second housing 21 and the third housing 31 from the airflow circulation mechanism 40, and the dry air is collected. Note that the airflow circulation mechanism 40 may be provided separately for each of the second housing 21 and the third housing 31.

[0031] 2A and 2B, the airflow circulation mechanism 40 has a pump 41, a first filter 42, and a second filter 43. The pump 41, the first filter 42, the second filter 43, and the first housing 11 of the laser light source 10 are connected in series by a main pipe 44.

[0032] Dry air discharged from the exhaust port 41A of the pump 41 passes through the first filter 42 and the second filter 43 and flows into the first housing 11 through the airflow inlet 11B. Furthermore, the dry air that flows out from the airflow outlet 11A into the main pipe 44 enters the intake port 41B of the pump 41 and is circulated through the exhaust port 41A via the same path.

[0033] The first filter 42 has a desiccant (not shown) that adsorbs moisture contained in the dry air flowing through the main pipe 44 and a filter (not shown) that adsorbs organic and other chemical substances, such as siloxane compounds, contained in the dry air. The second filter 43 removes dust particles and other particles contained in the dry air. Therefore, the dry air introduced into the main pipe 44 passes through the first filter 42 and is circulated inside the main pipe 44, thereby reducing the moisture content and organic content to below predetermined values. Similarly, the dry air passes through the second filter 43 and is circulated inside the main pipe 44, thereby reducing the number of dust particles per unit volume to below predetermined values.

[0034] The airflow circulation mechanism 40 also has an airflow collection mechanism 47. The airflow collection mechanism 47 is made up of a bypass pipe 44A, a collection tube housing 44D, a flow rate adjustment valve 45A, a first valve 45B, a second valve 45C, and a collection tube .

[0035] The bypass pipe 44A is connected to the main pipe 44, which connects the airflow outlet 11A of the first housing 11 and the intake port 41B of the pump 41, at a first connection point 44B and a second connection point 44C. In other words, the bypass pipe 44A is connected in parallel to the main pipe 44, which connects the airflow outlet 11A of the first housing 11 and the intake port 41B of the pump 41. A collection tube housing 44D is provided in the center of the bypass pipe 44A. Typically, the collection tube housing 44D is directly connected. When a cylindrical collection tube 46 is attached to the bypass pipe 44A, the collection tube 46 is housed in the collection tube housing 44D. When housed in the collection tube housing 44D, the collection tube 46 is in communication with the bypass pipe 44A. The collection tube 46 is detachably attached to the collection tube housing 44D, and the dry air flowing through the air circulation mechanism 40 is collected by the collection tube 46. This will be described in further detail later.

[0036] The flow rate control valve 45A is disposed in series with the main pipe 44 between the connection point with the bypass pipe 44A. The flow rate of dry air flowing through the main pipe 44 is adjusted by adjusting the opening of the flow rate control valve 45A. In addition, as will be described later, the flow rate of dry air flowing through the bypass pipe 44A is also adjusted.

[0037] The first valve 45B is disposed in series with a portion of the bypass piping 44A that extends from the first connecting point 44B. The second valve 45C is disposed in series with a portion of the bypass piping 44A that extends from the second connecting point 44C. The flow of dry air into the bypass piping 44A is controlled by operating the first valve 45B and the second valve 45C.

[0038] [Airflow circulation mechanism operation] 2A, during normal operation of the laser oscillator 80, the pump 41 is operated in response to a control command from the control unit 60. Dry air discharged from an exhaust port 41A of the pump 41 is circulated through the main pipe 44, which connects the first filter 42, the second filter 43, the first housing 11, and the pump 41. During this time, dry air does not flow through the bypass pipe 44A.

[0039] Furthermore, the dry air that has passed through the first filter 42 and the second filter 43 multiple times is also circulated inside the first housing 11. As a result, the amount of dust, the amount of moisture, and the amount of organic matter including siloxane compounds in the atmosphere inside the first housing 11 are each kept below a predetermined value.

[0040] On the other hand, the laser diode bar 12 generates a large amount of heat during operation, and even if a cooling mechanism (not shown) is provided inside the first housing 11, the temperature of the laser light source 10, including the first housing 11, rises over the course of operation. If a resin product is placed inside the first housing 11, some of the organic matter containing the siloxane compound may volatilize as the temperature rises, causing the siloxane concentration inside the first housing 11 to exceed a preset allowable value. Resin products include sealing materials used in pipe connections and circuit boards on which components are mounted.

[0041] If this occurs, as mentioned above, the photodecomposed siloxane compound may adhere as a deposit to the light-emitting end surface of the laser diode bar 12, which may cause a decrease in the output power and beam quality of the laser light emitted from each emitter.

[0042] Therefore, it is necessary to periodically measure the siloxane concentration in the atmosphere inside the first housing 11 to confirm that the siloxane concentration is below an allowable value. In the example shown in this embodiment, when measuring the siloxane concentration, first, the collection pipe 46 collects dry air flowing through the bypass pipe 44A.

[0043] In this case, as shown in FIG. 2B , the first valve 45B and the second valve 45C are opened. Furthermore, the aperture of the flow rate control valve 45A is adjusted to allow a predetermined flow rate of dry air to flow through the bypass pipe 44A. Because the resistance of the trapping pipe 46 to the flow of dry air is high, when the trapping pipe 46 is attached to the trapping pipe housing 44D, the resistance of the bypass pipe 44A becomes higher than that of the main pipe 44. Therefore, if the flow rate control valve 45A is not provided or if the flow rate control valve 45A is fully open, dry air will not flow through the bypass pipe 44A at the desired flow rate, and the required amount of dry air will not be collected by the trapping pipe 46. Therefore, the aperture of the flow rate control valve 45A must be adjusted.

[0044] After a predetermined amount of dry air has been collected in the collection tube 46, the first valve 45B and the second valve 45C are closed, and the collection tube 46 is removed from the collection tube housing 44D. The collection tube 46 is set in the sample housing 310 of the gas chromatography mass spectrometer 300 (hereinafter referred to as GC-MS300), and the siloxane concentration of the collected dry air is measured. After the measurement, the collection tube 46 is reattached to the collection tube housing 44D. Note that the laser oscillator 80 may be operating while the collection tube 46 is removed.

[0045] If the measured siloxane concentration is below the aforementioned allowable value, the laser oscillator 80 can be operated without any particular maintenance. On the other hand, if the siloxane concentration exceeds the allowable value, the operation of the laser oscillator 80 is stopped, and the necessary inspection and maintenance are performed. For example, the laser light source 10 is disassembled, the interior of the first housing 11 is inspected, and parts including the laser diode bar 12 are replaced if necessary. Parts other than the laser diode bar 12 may be cleaned and then reattached to the first housing 11. The first filter 42 is also inspected, and the organic filter is replaced if necessary.

[0046] The allowable value of the siloxane concentration inside the first housing 11 varies depending on the wavelength and output of the laser light. When the wavelength range of the laser light is from near ultraviolet to blue, in other words, the wavelength range is 370 nm or more and 460 nm or less, the allowable value is 1 μg / m 3 It is difficult to measure such low concentrations of siloxane using a commercially available volatile organic compound measuring instrument. Therefore, as shown in this embodiment, the dry air flowing through the first housing 11 is collected by the collection tube 46, and the siloxane concentration of the collected dry air is measured by the GC-MS 300.

[0047] [Effects, etc.] As described above, the laser oscillator 80 according to this embodiment includes at least the laser light source 10 and the airflow circulation mechanism 40. The laser light source 10 also includes at least the laser diode bar (semiconductor laser element) 12 that emits laser light, and the first housing 11 that houses the laser diode bar 12.

[0048] The air circulation mechanism includes at least a pump 41, a first filter 42, a main pipe 44, and an air collection mechanism 47.

[0049] The pump 41 circulates an airflow through a main pipe 44 connected to the laser light source. More specifically, the pump 41 circulates an airflow, in this case dry air, inside the first housing 11. The first filter 42 removes at least chemical substances contained in the dry air, typically siloxane compounds. The main pipe 44 is connected in series to the first housing 11, the pump 41, and the first filter 42, and serves as a flow path for the dry air. The airflow collecting mechanism 47 is provided between the intake port 41B of the pump 41 and the airflow outlet 11A of the first housing 11.

[0050] The air flow collecting mechanism 47 has a bypass pipe 44A, a collecting pipe 46, a flow rate adjustment valve 45A, a first valve 45B, and a second valve 45C. The bypass pipe 44A is connected to the main pipe 44 at a first connection point 44B and a second connection point 44C, and is connected in parallel to the main pipe 44. The collecting pipe 46 is arranged in series with the bypass pipe 44A. The collecting pipe 46 collects a portion of the dry air passing through the bypass pipe 44A. In addition, the bypass pipe 44A is provided with a collecting pipe housing 44D, and the collecting pipe 46 is detachable from the collecting pipe housing 44D.

[0051] The flow rate adjustment valve 45A is disposed in series in the main pipe 44 located between the first connection point 44B and the second connection point 44C. The first valve 45B is disposed in series in a portion of the bypass pipe 44A that extends from the first connection point 44B. The second valve 45C is disposed in series in a portion of the bypass pipe 44A that extends from the second connection point 44C.

[0052] By configuring the laser oscillator 80 in this manner, it is possible to collect dry air flowing inside the first housing 11 without stopping the operation of the laser oscillator 80, i.e., the laser light source 10. Furthermore, when deposits formed by photodecomposition of the siloxane compound accumulate on the light-emitting end faces of the laser diode bars 12 and become thick, laser light is absorbed at the light-emitting end face, causing thermal destruction of the light-emitting end face and preventing the emission of laser light.

[0053] According to this embodiment, by collecting dry air flowing inside the first housing 11 and measuring the siloxane concentration, it is possible to determine whether the laser oscillator 80 is operable and perform maintenance on the laser oscillator 80 at an appropriate timing. This makes it possible to suppress a decrease in the output and beam quality of the laser light emitted from the laser source 10, and ultimately the processing laser light LB emitted from the laser oscillator 80. Furthermore, the laser diode bar 12 can be replaced at an appropriate timing before it is damaged.

[0054] On the other hand, if the airflow collecting mechanism 47 is not provided, it is difficult to collect the dry air flowing inside the first housing 11.

[0055] Fig. 3 is a schematic diagram of the main parts of a laser oscillator according to a comparative example. The laser oscillator 80 shown in Fig. 3 differs from the laser oscillator 80 of the present embodiment shown in Figs. 2A and 2B in that it does not include an airflow collecting mechanism 47.

[0056] In the laser oscillator shown in FIG. 3 , it was necessary to stop operation of the laser oscillator 80 and remove the main pipe 44 connected to the first housing 11 to collect the dry air flowing inside the first housing 11. However, this method requires stopping the laser oscillator 80 every time the siloxane concentration is measured, resulting in extended downtime for the laser oscillator 80. Furthermore, when the main pipe 44 is removed, the alignment of the optical system of the laser oscillator 80 may be shifted due to reattachment work, etc. This necessitates readjustment of the optical system, further extending downtime. Furthermore, removing and reattaching the main pipe 44 may introduce air and dust contained therein from the outside into the first housing 11. In this case, moisture, organic matter, and dust may adhere to the light-emitting end faces of the laser diode bars 12 and the surfaces of the optical components inside the first housing 11, potentially resulting in reduced laser light output and beam quality.

[0057] On the other hand, according to the present embodiment, maintenance of the laser oscillator 80 can be performed at an appropriate time by collecting dry air flowing inside the first housing 11 and measuring the siloxane concentration without stopping the operation of the laser oscillator 80. In other words, unnecessary maintenance is not performed, and prolonged downtime of the laser oscillator 80 can be suppressed.

[0058] Furthermore, when the collection tube 46 is removed, the bypass pipe 44A is opened, which may temporarily allow external air and dust contained therein to enter the main pipe 44. If the airflow collection mechanism 47 is provided, for example, between the second filter 43 and the airflow inlet 11B of the first housing 11 shown in FIGS. 2A and 2B, moisture, organic matter, and dust that have entered with the air may flow directly into the first housing 11 without being removed. If this occurs, as described above, this may cause a decrease in the output power and beam quality of the laser light.

[0059] On the other hand, according to the present embodiment, the air flow collecting mechanism 47 is provided between the intake port 41B of the pump 41 and the air flow outlet 11A of the first housing 11. In this manner, even if air gets into the main pipe 44 when the collection tube 46 is removed, the first filter 42 and the second filter 43 can properly remove the mixed moisture, organic matter, and dust. From the viewpoint of properly removing the mixed moisture, organic matter, and dust, the air flow collecting mechanism 47 may be provided between the exhaust port 41A of the pump 41 and the first filter 42.

[0060] During normal operation of the laser oscillator 80, the first valve 45B and the second valve 45C are closed, and the flow rate control valve 45A is open. When collecting dry air in the collection pipe 46, the first valve 45B and the second valve 45C are open, and the aperture of the flow rate control valve 45A is adjusted so that a predetermined flow rate of dry air flows through the bypass pipe 44A.

[0061] In this way, the dry air flowing inside the first housing 11 can be collected without stopping the operation of the laser oscillator 80 and by only slightly reducing the flow rate of the dry air flowing through the main pipe 44.

[0062] It is preferable that the first filter 42 further be provided with a desiccant for removing moisture contained in the dry air. If the moisture content of the dry air exceeds an allowable value, condensation or the like may occur inside the first housing 11, which may cause a decrease in the output power of the laser light or a deterioration in the beam quality.

[0063] By providing a desiccant in the path of the main pipe 44 between the exhaust port 41A of the pump 41 and the air flow inlet 11B of the first housing 11, condensation and the like can be prevented inside the first housing 11, and a decrease in the output of the laser light and a decrease in the beam quality can be suppressed.

[0064] It is preferable that a second filter 43 for removing dust contained in the dry air is provided between the exhaust port 41A of the pump 41 and the airflow inlet 11B of the first housing 11. This prevents dust from adhering to the light-emitting end faces of the laser diode bars 12 and the surfaces of the optical components inside the first housing 11, thereby suppressing a decrease in the output power of the laser light and a decrease in the beam quality.

[0065] 1, consider a case where a plurality of laser light sources 10 are provided in the laser oscillator 80, in other words, a case where a plurality of first housings 11 are provided and one or a plurality of laser diode bars 12 are arranged in each of the plurality of first housings 11. In this case, it is preferable that an airflow circulation mechanism 40 is connected to each of the plurality of first housings 11.

[0066] In this way, it is possible to collect the dry air flowing inside each of the plurality of first housings 11 without stopping the operation of the laser oscillator 80. Furthermore, by measuring the siloxane concentration of the collected dry air, it is possible to perform maintenance on the laser oscillator 80 at an appropriate timing. In other words, unnecessary maintenance is not performed, and prolonged downtime of the laser oscillator 80 can be suppressed.

[0067] It is preferable that one pump 41, one first filter 42, and one second filter 43 are commonly connected to each of the plurality of first housings 11. In this way, an increase in the number of pieces of equipment in the laser oscillator 80 can be suppressed, and an increase in the cost of the laser oscillator 80 can be suppressed.

[0068] It is also possible to provide a common air flow collecting mechanism 47 for each of the multiple first housings 11. In this case, it is possible to prevent an increase in the number of installed air flow collecting mechanisms 47, and to prevent an increase in the cost of the laser oscillator 80. It is also possible to provide an individual air flow collecting mechanism 47 for each of the multiple first housings 11. In this case, it is possible to easily identify, among the multiple laser light sources 10, the laser light source 10 in which the siloxane concentration inside the first housing 11 is high.

[0069] Furthermore, when a plurality of laser light sources 10 are provided, a beam combiner 20 is provided. The beam combiner 20 has a second housing 21 and combines the laser beams emitted from the plurality of laser diode bars 12 into a single processing laser beam LB. In this case, as described above, it is preferable that the airflow circulation mechanism 40 is connected to the second housing 21.

[0070] As described above, multiple optical components (not shown) are disposed inside the second housing 21. The output of the processing laser light LB is four times the output of the laser light emitted from one laser light source 10. When a high concentration of siloxane compounds is present in the atmosphere inside the second housing 21 and the processing laser light LB passes through these optical components, the photodecomposed siloxane compounds adhere to and deposit on the surfaces of the optical components. When the processing laser light LB is absorbed by these deposits, the deposits, and ultimately the optical components, generate heat, which can change the optical characteristics or, in extreme cases, damage the optical components.

[0071] As described above, by connecting the airflow circulation mechanism 40 to the second housing 21, it is possible to collect the dry air flowing inside the second housing 21. Furthermore, by measuring the siloxane concentration of the collected dry air, it is possible to perform maintenance on the beam combiner 20 at an appropriate time. This makes it possible to prevent the aforementioned deposits from adhering excessively to the surfaces of the optical components, maintain the optical properties of the optical components, and suppress a decrease in the output of the processing laser light LB and a decrease in beam quality. Furthermore, since unnecessary maintenance is not performed, it is possible to suppress prolonged downtime of the laser oscillator 80.

[0072] It is also possible to provide an air flow collecting mechanism 47 in common to each of the plurality of first housings 11 and the second housing 21. In this case, it is possible to prevent an increase in the number of air flow collecting mechanisms 47 installed, and to prevent an increase in the cost of the laser oscillator 80. It is also possible to provide an air flow collecting mechanism 47 individually to the second housing 21. In this case, it is possible to easily identify, among the plurality of laser light sources 10 and the beam combiner 20, those having a high internal siloxane concentration.

[0073] The laser oscillator 80 is also provided with a focusing optical unit 30. The focusing optical unit 30 has a third housing 31, and focuses the processing laser light LB toward the incident end of the optical fiber 90. When there is one laser light source 10, the focusing optical unit 30 focuses the laser light emitted from the laser light source 10 toward the incident end of the optical fiber 90. In this case, as described above, it is preferable that the airflow circulation mechanism 40 is connected to the third housing 31.

[0074] A plurality of optical components, including a condensing lens, are also arranged inside the third housing 31. As described above, by connecting the airflow circulation mechanism 40 to the third housing 31, the dry air flowing inside the third housing 31 can be collected. Furthermore, by measuring the siloxane concentration of the collected dry air, maintenance of the collecting optical unit can be performed at an appropriate time. This prevents deposits generated by photodecomposition of the siloxane compound from excessively adhering to the surfaces of optical components, including the condensing lens, maintaining the optical properties of the optical components and suppressing a decrease in the output of the processing laser light LB and a deterioration in beam quality. Furthermore, since unnecessary maintenance is not performed, prolonged downtime of the laser oscillator 80 can be suppressed.

[0075] As described above, the allowable siloxane concentration inside the first to third housings 11, 21, and 31 varies depending on the wavelength and output of the laser light. Generally, the higher the output of the laser light, the faster the photodecomposition rate of the siloxane compound, so the allowable siloxane concentration must be lowered. Furthermore, when the wavelength of the laser light falls below a predetermined value, the photodecomposition of the siloxane compound begins, so the allowable siloxane concentration must be lowered.

[0076] When the energy of the laser beam exceeds the bond energy of silicon-oxygen (-Si-O-) or silicon-carbon (-Si-C-) in the siloxane compound, these bonds are broken, generating a gas containing siloxane in the atmosphere. When this gas adheres to the light-emitting end faces of the laser diode bars 12 or the surfaces of optical components, the aforementioned deposits are generated.

[0077] Wavelength ranges commonly used in laser processing include the so-called near-infrared range of approximately 900 nm to 1200 nm, the so-called green range of approximately 500 nm to 570 nm, and the so-called blue range of approximately 400 nm to 460 nm. Of these, the energy of laser light in the near-infrared range is lower than the bond energy of the silicon-oxygen and silicon-carbon bonds mentioned above. Therefore, in this case, although heat generated according to the output of the laser light may volatilize organic matter and generate gas containing siloxane, photodecomposition of siloxane compounds does not generally occur.

[0078] On the other hand, the energy of blue laser light is higher than the bond energy of silicon-oxygen and silicon-carbon. Therefore, in an atmosphere where the siloxane concentration is higher than the allowable value, the photodecomposition reaction of siloxane compounds generates gas containing siloxane, and if this gas adheres to the light-emitting end faces of the laser diode bars 12 or the surfaces of optical components, there is a high possibility that deposits will be formed. This tendency becomes more pronounced when the wavelength range of the laser light is shorter than that of blue, from the near-ultraviolet to the ultraviolet range. When the wavelength range of the laser light is green, photodecomposition of siloxane compounds is less likely to occur than when it is blue, but deposits may still be formed.

[0079] Considering these points, the laser oscillator 80 in this embodiment is useful when the wavelength range of the laser light emitted from the laser light source 10 is from the ultraviolet range to green, in other words, 270 nm or more and 570 nm or less. In particular, it is even more useful when the wavelength range of the laser light is from the near ultraviolet range to blue, in other words, 370 nm or more and 460 nm or less.

[0080] In these cases, the adhesion of siloxane increases the likelihood of deposits forming on the light-emitting end faces of the laser diode bars 12 and on the surfaces of the optical components. As shown in this embodiment, by collecting the dry air flowing through the laser oscillator 80 and measuring its siloxane concentration periodically or as needed, it is possible to prevent excessive adhesion of deposits to the light-emitting end faces of the laser diode bars 12 and on the surfaces of the optical components. This makes it possible to maintain the optical properties of the laser diode bars 12 and the optical components and to suppress a decrease in the output of the processing laser light LB and a decrease in beam quality.

[0081] The laser processing device 200 according to this embodiment includes at least a laser oscillator 80 and a laser head 100 that receives processing laser light LB emitted from the laser oscillator 80 and irradiates the workpiece W with the laser light LB.

[0082] By configuring the laser processing apparatus 200 in this manner, the dry air flowing inside the laser oscillator 80 can be collected and the siloxane concentration can be measured, allowing maintenance of the laser oscillator 80 at an appropriate time without stopping the operation of the laser oscillator 80. In other words, unnecessary maintenance can be avoided, and prolonged downtime of the laser oscillator 80, and therefore of the laser processing apparatus 200, can be suppressed.

[0083] Furthermore, by collecting the dry air flowing through the laser oscillator 80 and measuring its siloxane concentration periodically or as needed, it is possible to prevent deposits from excessively adhering to the light-emitting end faces of the laser diode bars 12 and the surfaces of the optical components, thereby maintaining the optical characteristics of the laser diode bars 12 and the optical components and suppressing a decrease in the output of the processing laser light LB and a decrease in beam quality.

[0084] In the present specification, the airflow flowing through the laser oscillator 80 is dry air, but this is not particularly limited. For example, nitrogen gas in which the amounts of moisture, organic matter, and dust have been adjusted may flow through the laser oscillator 80. [Industrial Applicability]

[0085] The laser oscillator of the present disclosure is useful because it can collect airflow from a flow path connected to a laser source without shutting down the laser source. [Explanation of symbols]

[0086] 10 Laser light source 11 First cabinet 11A Airflow outlet 11B Airflow inlet 12 Laser diode bar (semiconductor laser element) 20 Beam combiner 21 Second cabinet 30 Condenser optical unit 31 Third cabinet 40 Airflow circulation mechanism 41 Pump 41A Exhaust port 41B Air intake 42 First filter 43 Second Filter 44 Main Pipe 44A Bypass piping 44B First connection point 44C Second connection point 44D Collection tube housing 45A flow control valve 45B First valve 45C Second valve 46 Collection tube 47 Airflow collection mechanism 50 4th cabinet 60 Control Unit 61 Display section 70 Power supply 80 Laser Oscillator 90 Optical Fiber 100 laser head 200 Laser processing equipment 300 Gas Chromatography Mass Spectrometer 310 Sample storage section LB laser beam for processing double work

Claims

1. a laser light source that emits laser light; an airflow circulation mechanism; The airflow circulation mechanism includes: a pump that circulates airflow inside the laser light source; a first filter that removes at least chemical substances contained in the airflow; a main pipe connected in series to the laser light source, the pump, and the first filter, and serving as a flow path for the airflow; an airflow collecting mechanism provided between an intake port of the pump and an airflow outlet of the laser light source, The airflow collecting mechanism includes: a bypass pipe connected to the main pipe at a first connection point and a second connection point and connected in parallel to the main pipe; a collection tube arranged in series with the bypass piping; a flow control valve disposed in series in the main pipe between the first connection point and the second connection point; a first valve disposed in series in a portion of the bypass pipe that is provided so as to extend from the first connection point; a second valve disposed in series in a portion of the bypass pipe that is provided so as to extend from the second connection point, A laser oscillator, characterized in that a part of the air flow passing through the bypass piping is collected by the collection pipe.

2. 2. The laser oscillator according to claim 1, the laser light source has at least a semiconductor laser element and a first housing that houses the semiconductor laser element; The laser oscillator is characterized in that the main pipe is connected to the first housing, and the air flow flows inside the first housing.

3. 2. The laser oscillator according to claim 1, 10. A laser oscillator according to claim 9, wherein the first filter is further provided with a desiccant for removing moisture contained in the airflow.

4. 2. The laser oscillator according to claim 1, A laser oscillator characterized in that the bypass pipe is provided with a collection tube housing, and the collection tube is detachably attached to the collection tube housing.

5. 2. The laser oscillator according to claim 1, a second filter for removing dust contained in the airflow, the second filter being provided between the exhaust port of the pump and the airflow inlet of the laser light source;

6. 2. The laser oscillator according to claim 1, During normal operation, the first valve and the second valve are in a closed state, and the flow rate adjustment valve is in an open state. a laser oscillator characterized in that, when the airflow is collected by the collection pipe, the first valve and the second valve are in an open state, and the opening of the flow rate control valve is adjusted so that the airflow flows through the bypass piping at a predetermined flow rate.

7. 3. The laser oscillator according to claim 2, a plurality of the first housings are provided, and the semiconductor laser element is disposed in each of the plurality of first housings; A laser oscillator, characterized in that the airflow circulation mechanism is connected to each of the plurality of first housings.

8. 8. The laser oscillator according to claim 7, a beam combiner having a second housing and combining the laser beams emitted from the plurality of semiconductor laser elements into a single processing laser beam; The laser oscillator is characterized in that the airflow circulation mechanism is connected to the second housing.

9. 2. The laser oscillator according to claim 1, a focusing optical unit having a third housing and configured to focus at least the laser light; The laser oscillator is characterized in that the airflow circulation mechanism is connected to the third housing.

10. 2. The laser oscillator according to claim 1, A laser oscillator characterized in that the wavelength of the laser light is 270 nm or more and 570 nm or less.

11. 11. The laser oscillator according to claim 10, A laser oscillator characterized in that the wavelength of the laser light is 370 nm or more and 460 nm or less.

12. 2. The laser oscillator according to claim 1, The laser oscillator is characterized in that the chemical substance includes at least a siloxane compound.

13. A laser oscillator according to any one of claims 1 to 12; a laser processing head that receives the processing laser light emitted from the laser oscillator and irradiates the light toward a workpiece.

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