JP2008091444A - Gas laser oscillator and laser machining system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a three-axis orthogonal gas laser oscillator for individually generating independent two or more laser beams in the desired output with a comparatively compact structure and for individually adjusting quality of each laser beam. <P>SOLUTION: A couple of independent laser oscillators, each of which is formed of a pair of electrodes 2, 3 constituted with a couple of plate electrodes having a longer axis and a shorter axis in the face-to-face relationship and corresponding optical resonators 25a, 25b, are arranged in the vertical direction keeping the predetermined interval within a vacuum vessel 1 filled with a mixed gas as the laser medium. Moreover, a blower 10 for supplying a mixed gas through circulation while cooling the same mixed gas from the short axis direction to a discharge gap in each independent laser oscillation system, a heat exchanger 11 and a gas duct 12 are also arranged in the same vacuum vessel 1. Electrical power applied to a pair of electrodes 2, 3 is controlled independently. Structural components of the optical resonators 25a, 25b are selected to ensure the desired quality of the generated laser beams 26a, 26b. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a gas laser oscillator referred to as a three-axis orthogonal type and a laser processing system that performs simultaneous processing on a plurality of axes using the three-axis orthogonal type gas laser oscillator.

  FIG. 8 is a block diagram illustrating a configuration example of a conventional laser processing system. In the laser processing system, high productivity is required, not to mention processing quality. For example, as shown in FIG. 8, a plurality of laser beams emitted from the laser light source are emitted (two in the example shown in FIG. 8). Is applied to a workpiece (two workpieces in the example shown in FIG. 8) and enables simultaneous machining on multiple axes (two axes in the example shown in FIG. 8). There is.

  The laser processing system shown in FIG. 8 has a laser oscillator 40 that emits one laser beam 46 as a laser light source, two work tables 41a and 41b on which works 42a and 42b are respectively mounted, and an emission of the laser oscillator 40. An optical system 43a, 43b, 43c for transmitting the laser beam 46 to the workpieces 42a, 42b mounted on the two work tables 41a, 41b, respectively, and a control device 44 for controlling each of these elements are provided.

  The operation will be described. The laser oscillator 40 is a gas laser oscillator here, but performs laser oscillation under the control of laser oscillation conditions (timing, intensity, time width) from the control device 44, and outputs a laser beam 46 to the optical system 43a. .

  Under the control of the control device 44, the optical system 43a distributes the emitted laser beam 46 of the laser oscillator 40 in two directions, the path to the optical system 43b and the path to the optical system 43c, by the energy division method or the time division method. The energy division method is a method of dividing an incident laser beam into two paths by dividing the energy. In addition, the time division method is a method in which an incident laser beam is time-divided into two paths using an optical switching element such as an acousto-optic deflection element.

  The optical system 43b shapes the laser beam 46a incident from the optical system 43a under the control of the control device 44, and two-dimensionally scans and condenses and irradiates the work 42a placed on the work table 41a. 47a is generated. Similarly, the optical system 43c shapes the laser beam 46b incident from the optical system 43a under the control of the control device 44, and condenses and irradiates the work 42b placed on the work table 41b by two-dimensional scanning. The laser beam 47b to be generated is generated.

  Here, processing quality and productivity important as evaluation items of the laser processing system are determined as follows in the configuration example shown in FIG.

  That is, the processing quality is determined by the spatial beam mode of the laser beam irradiated to the workpiece 42 (a, b) determined by the laser oscillator 40 or the optical system 43 (a, b, c), or the laser irradiated per unit time. It is determined by a temporal beam irradiation method such as pulse energy or beam irradiation pause time.

  Further, the productivity is determined by the laser output to the workpiece 42 (a, b) determined by the output loss in the laser oscillator 40 or the optical system 43 (a, b, c), or the optical system 43 (a, b, c). ) And the moving speed of the beam irradiation position determined by the control device 44 that controls it, the moving speed of the work table 41 (a, b) holding the work 42 (a, b), the beam to be irradiated at once It is determined by the number.

  Thus, it is no exaggeration to say that both processing quality and productivity important for the performance of the laser processing system are determined by the laser oscillator 40 and the optical system 43 (a, b, c). Since the laser oscillator 40 is required to have a high output, a gas laser oscillator referred to as a three-axis orthogonal type will be described as a gas laser oscillator that enables a high output.

  9 and 10 are conceptual diagrams showing a configuration example of a conventional three-axis orthogonal gas laser oscillator. 9 is a cross-sectional view along the optical axis direction, and FIG. 10 is a cross-sectional view along the direction perpendicular to the optical axis.

  9 and 10, the vacuum vessel 50 is filled with a mixed gas that is a laser medium. A plate-like discharge electrode having a predetermined length (major axis), width (minor axis), and thickness on the upper side in the height direction in the vacuum container 50 in the vacuum container 50 in the illustrated example. 51a and 51b are opposed to each other with a predetermined discharge gap.

  For this pair of discharge electrodes 51a and 51b, a semi-transparent partial reflecting mirror (PR) 52 is disposed on one end side in the major axis direction, and a total reflecting mirror (TR) 53 is disposed on the other end side. Further, a transverse mode limiting aperture 54 that defines the oscillation mode of laser oscillation is interposed between the other end in the major axis direction of the discharge electrodes 51a and 51b and the total reflection mirror 53. That is, the major axis direction of the discharge electrodes 51a and 51b is the laser optical axis direction.

  And the air blower 55 and the heat exchanger 56 are arrange | positioned in the lower stage side of the height direction in the vacuum vessel 50, and the gas duct 57 is provided between the air blower 55 and the discharge gap of discharge electrode 51a, 51b. A gas flow 58a of a mixed gas, which is a laser medium blown out by the blower 55 at high speed, is supplied from the gas duct 57 to the discharge gap of the discharge electrodes 51a and 51b from the lateral direction that is the short axis direction, and the gas flow that has passed through the discharge gap. A circulating gas supply path for taking 48b into the blower 55 is formed. The heat exchanger 56 is provided in the course of the returning gas flow 58b.

  In the above configuration, by applying high frequency power to the discharge electrodes 51a and 51b, an excitation discharge 60 is formed between the electrodes (discharge gap), and the partial reflection mirror 52, the transverse mode limiting aperture 54, and the total reflection mirror 53 are formed. Laser oscillation is performed by the optical resonator configured as follows, and the laser beam 61 is output from the partial reflection mirror 52 to the outside of the vacuum vessel 50.

  At this time, if the input power is large, the temperature of the excited gas increases and the excitation efficiency decreases, so that the high temperature gas in the discharge gap of the discharge electrodes 51a and 51b is always supplied by the blower 55, the gas duct 57 and the heat exchanger 56. It is designed to flow completely in the horizontal direction while cooling. As a result, in the optical resonator, the excitation discharge 60 is always maintained in a state in which high oscillation efficiency can be obtained, so that a high laser output can be stably obtained.

  As described above, the gas laser oscillator configured as shown in FIGS. 9 and 10 is named “3-axis orthogonal type” because the discharge direction, the gas flow direction, and the laser optical axis direction are orthogonal to each other. However, it is known as a gas laser oscillator suitable for high output.

  By the way, in the configuration shown in FIGS. 9 and 10, in order to realize further higher output, either a method of increasing the discharge volume or a method of increasing the discharge power density is required. To increase the discharge volume, the entire laser oscillator may be enlarged. On the other hand, in order to increase the discharge power density, it is necessary to develop a power source for increasing the input power. For reasons such as technical difficulties, measures will be taken to enlarge the entire laser oscillator.

  However, since this measure goes against the demand for miniaturization, a three-axis orthogonal gas laser oscillator that can prevent the enlargement of the laser oscillator and aim for higher output with a relatively compact configuration has been proposed. (For example, Patent Documents 1 and 2). The outline is shown below.

  For example, Patent Document 1 discloses a three-axis orthogonal gas laser oscillator having the configuration shown in FIGS. 11 and 12 (hereinafter referred to as “improved example 1”). 11 is a cross-sectional view along the optical axis direction, and FIG. 12 is a cross-sectional view along the direction perpendicular to the optical axis.

  11 and 12, three discharge electrodes 70a, 70b, and 70c are arranged on the upper side in the height direction in the vacuum vessel 50 so as to overlap each other with a predetermined discharge gap. For the pair of discharge electrodes 70b and 70a, a total reflection mirror (TR) 71 is disposed on one end in the long axis direction, and a folding mirror 72a is disposed on the other end in the long axis direction. Yes. For the other pair of discharge electrodes 70b and 70c, a semi-transparent partial reflecting mirror (PR) 73 is disposed on one end side in the long axis direction, and a folding mirror is provided on the other end side in the long axis direction. 72b is arranged to face the folding mirror 72a in an inclined state.

  And the air blower 55 and the heat exchanger 56 are arrange | positioned in the lower stage side of the height direction in the vacuum vessel 50, and a gas duct is provided between the air blower 55 and each discharge gap of the discharge electrodes 60b and 60a and the discharge electrodes 60b and 60c. 75 is provided. By this gas duct 75, the gas flow 76 of the mixed gas, which is a laser medium blown out at high speed by the blower 55, is bifurcated into gas flows 76a and 76b in the same direction in the discharge gaps of the discharge electrodes 70b and 70a and the discharge electrodes 70b and 70c. A circulation gas supply path is formed in which the gas flows 77a and 77b supplied from the lateral direction of the gas and passing through the respective discharge gaps are taken into the blower 55 as one return gas flow 77. The heat exchanger 56 is provided in the course of the return gas flow 77.

  In the above configuration, the middle discharge electrode 70b is a common electrode (high potential), the discharge electrodes 70a and 70c on both sides are low potential, and the discharge electrodes 70b and 70a forming one pair and the other discharge electrode are formed. By applying high-frequency power between the electrodes 70b and 70c, excitation discharges 78a and 78b are formed between the electrodes (discharge gap), respectively, and the partial reflection mirror 73, the folding mirrors 72a and 72b, the total reflection mirror 71, and the like. Laser oscillation is performed by one optical resonator configured as follows, and a laser beam 79 is output from the partial reflection mirror 73 to the outside of the vacuum vessel 50.

  According to the improved example 1, the excitation resonance space can be formed in the optical axis direction twice as compared with the configuration shown in FIGS. 9 and 10 to generate optical resonance. Further higher output than the configuration shown in FIGS. 9 and 10 can be achieved.

  Next, for example, Patent Document 2 discloses a three-axis orthogonal gas laser oscillator having the configuration shown in FIGS. 13 and 14 (hereinafter referred to as “improved example 2”). 13 is a cross-sectional view along the optical axis direction, and FIG. 14 is a cross-sectional view along the direction perpendicular to the optical axis.

  13 and 14, one pair of discharge electrodes 80 a and 80 b and the other pair of discharge electrodes 81 a and 81 b are arranged at a predetermined interval on the same plane on the upper side in the height direction in the vacuum vessel 50. And the cooler 82 is disposed in the gas flow path between the discharge electrodes 80a and 80b and the discharge electrodes 81a and 81b.

  For this pair of discharge electrodes 80a and 80b, a semi-transparent partial reflecting mirror (PR) 83 is disposed at one end in the long axis direction, and a folding mirror 84a is disposed at the other end in the long axis direction. In addition, for the other pair of discharge electrodes 81a and 81b, a total reflection mirror (TR) 85 is disposed at one end in the long axis direction, and a folding mirror 83a is disposed at the other end in the long axis direction. A folding mirror 83b that faces in an inclined state is arranged.

  The blower 55 and the heat exchanger 56 are arranged on the lower side in the height direction in the vacuum vessel 50, and a diagram is provided between the blower 55 and the discharge gaps of the discharge electrodes 81a and 81b and the discharge electrodes 82a and 82b. 9 and a gas duct 57 having the same configuration as in FIG. 10 is provided. In the illustrated example, the discharge gas flow 58a of the blower 55 flows by the gas duct 57 from the discharge gap of the discharge electrodes 80a and 80ba → the cooler 82 → the discharge gap of the discharge electrodes 81a and 81b, and the discharge electrodes 81a and 81b. From the discharge gap, the gas flow 58b is returned to the blower 55.

  In the above configuration, high-frequency power having the same polarity is applied between the discharge electrodes 80a and 80b forming one pair and between the discharge electrodes 81a and 81b forming the other pair, so that the distance between the electrodes (discharge gap) is reduced. Excitation discharges 86a and 86b are respectively formed in the laser beam, and laser oscillation is performed by a single optical resonator composed of a partial reflection mirror (PR) 83, folding mirrors 84a and 84b, and a total reflection mirror (TR) 85. A laser beam 87 is output from the reflecting mirror (PR) 83 to the outside of the vacuum vessel 50.

  According to this modified example 2, optical resonance can be generated by forming twice the excitation discharge space in the gas flow direction (short axis direction) as compared with the configuration shown in FIG. 9 and FIG. With this configuration, higher output can be achieved than the configurations shown in FIGS.

Japanese Patent Laid-Open No. 7-142786 (FIG. 1) Japanese Patent Laying-Open No. 2003-218434 (FIG. 5)

  However, in the above-described modified examples 1 and 2, it is possible to prevent the three-axis orthogonal gas laser oscillator from becoming enormous and to achieve a high output with a relatively compact configuration, but the output of one laser beam is increased. Therefore, not only the load on the mirror of the optical resonator increases, but also the load on the optical components in the optical system that transmits the laser beam to the workpiece in the laser processing system using it as a laser light source increases. However, there is a problem that stability and life are deteriorated.

  Further, since the conventional three-axis orthogonal gas laser oscillator is configured to output one laser beam, in order to configure a multi-axis laser processing system using one of the laser beams as a laser light source, the number of beams is used as energy. It increases to 2 or more by the division method or the time division method. FIG. 8 shows a case where one emitted laser beam is divided into two, and one workpiece is associated with each of them. However, if the number of workpieces to be processed simultaneously is small relative to the number of beams, production is performed. There are cases where the improvement of sex cannot be achieved.

  That is, in a multi-axis laser processing system using an energy division method, when a plurality of laser beams having different processing patterns are irradiated on one workpiece, for example, two laser beams having different processing patterns are applied to one workpiece. However, if one of the two laser beams is received by a damper in the optical path, an increase in the number of discarded laser beams will hinder productivity.

  On the other hand, in a multi-axis laser processing system using a time division method, if the pulse repetition response speed of the laser oscillator does not have a response speed that is about twice the maximum positioning speed of the optical system, there is a waiting time in beam irradiation. This will hinder productivity.

  The present invention has been made in view of the above, and can independently generate two or more independent laser beams at a desired output with a relatively compact configuration, and each laser beam has its quality individually. An object of the present invention is to obtain a three-axis orthogonal type gas laser oscillator that can be adjusted to the above.

  Another object of the present invention is to obtain a multi-axis laser processing system with good processing quality and high productivity by using the three-axis orthogonal gas laser oscillator according to the present invention as a laser light source.

  In order to achieve the above-described object, a gas laser oscillator according to the present invention has a gap between two plate electrodes having a major axis and a minor axis in a single container filled with a mixed gas as a laser medium. Laser oscillation based on the excitation discharge is performed by a discharge electrode pair that forms an excitation discharge corresponding to input power in a certain discharge gap, and a total reflection mirror and a partial reflection mirror that are arranged opposite to each other across the major axis direction of the discharge electrode pair. And at least two independent laser oscillation systems each including an optical resonator that emits a laser beam to the outside from the partial reflection mirror, and all the laser oscillation systems are arranged side by side in the opposing arrangement direction of the discharge electrode pair And cooling the mixed gas supplied to the discharge gap in each of the independent laser oscillation systems as a gas flow passing from one end side to the other end side in the minor axis direction. Gas circulation supply means for reluctant circulated, characterized in that is arranged.

  According to the present invention, at least two independent laser oscillation systems are provided in one container, but each laser oscillation system does not need to be increased in size, so that a multi-beam can be output with a relatively compact configuration. An axially orthogonal gas laser oscillator can be obtained.

  According to the present invention, it is possible to obtain a three-axis orthogonal gas laser oscillator capable of outputting two or more independent laser beams with a relatively compact configuration.

  Exemplary embodiments of a three-axis orthogonal gas laser oscillator and a multi-axis laser processing system according to the present invention will be described below in detail with reference to the drawings.

Embodiment 1 FIG.
1 and 2 are conceptual diagrams showing a configuration of a three-axis orthogonal gas laser oscillator according to Embodiment 1 of the present invention. 1 is a cross-sectional view along the optical axis direction, and FIG. 2 is a cross-sectional view along the direction perpendicular to the optical axis.

  1 and 2, the first electrode pair 2 is provided in the vacuum container 1 filled with a mixed gas as a laser medium, in the illustrated example, on the upper side in the height direction in the vacuum container 1. The discharge electrodes 2a and 2b and the discharge electrodes 3a and 3b, which are the second electrode pair 3, are arranged side by side at appropriate intervals in the opposing arrangement direction of the discharge electrodes in each electrode pair with the major axis direction aligned in the same direction. ing.

  In addition, between the discharge electrode 2b and the discharge electrode 3a, the insulation distance which considered the maximum potential difference was calculated | required by experiment etc., the safety factor was considered, and it has arrange | positioned so that it may become the space | interval beyond it. Specifically, for example, the distance between the discharge electrode 2b and the discharge electrode 3a is 1.5 to 2 times or more of the discharge gap between the discharge electrodes 2a and 2b and the discharge gap between the discharge electrodes 3a and 3b. It has been arranged. However, the distance between the discharge electrode 2b and the discharge electrode 3a can be reduced by increasing the insulation by inserting an insulating material between the discharge electrode 2b and the discharge electrode 3a or enclosing a high-pressure gas. Is possible.

  For the discharge electrodes 2a, 2b and the discharge electrodes 3a, 3b, semi-transparent partial reflecting mirrors (PR) 4, 5 are respectively arranged on one end side in the major axis direction, and a total reflecting mirror is arranged on the other end side. (TR) 6 and 7 are arranged. Further, a transverse mode limiting aperture 8 is arranged between the other end side in the long axis direction of the discharge electrodes 2a and 2b and the total reflection mirror (TR) 6, and the other end side in the long axis direction of the discharge electrodes 3a and 3b and the entire other side. A transverse mode limiting aperture 9 is arranged between the reflector (TR) 7 and the reflector 9.

  In short, the first electrode pair 2 (discharge electrodes 2a and 2b) and the first optical resonator 25a (partial reflection mirror (PR) 4, total reflection mirror (TR) 6 and transverse mode limiting aperture 8) are provided. One independent laser oscillation system is configured. Similarly, the second electrode pair 3 (discharge electrodes 3a and 3b), the first optical resonator 25b (partial reflecting mirror (PR) 5, total reflecting mirror (TR) 7 and transverse mode limiting aperture 9) and Constitutes an independent laser oscillation system.

  And the air blower 10 and the heat exchanger 11 are arrange | positioned in the lower stage side of the height direction in the vacuum vessel 1, and the gas duct 12 is provided between the air blower 10 and each discharge gap of the discharge electrodes 2a and 2b and the discharge electrodes 3a and 3b. Is provided. The gas duct 12 divides the gas flow 15 of the mixed gas, which is a laser medium blown out by the blower 10 at a high speed, into two gas flows 15a and 15b, in the same direction in the discharge gaps of the discharge electrodes 2a and 2b and the discharge electrodes 3a and 3b. A circulating gas supply path is formed in which the gas flows 16 a and 16 b supplied from the lateral direction of the gas and passing through the respective discharge gaps are taken into the blower 10 as one feedback gas flow 16. The heat exchanger 11 is provided in the course of the return gas flow 16.

  Next, the operation of the three-axis orthogonal gas laser oscillator shown in FIG. 1 will be described. First, FIG. 3 is a diagram for explaining the relationship between the two pairs of discharge electrodes, the high-frequency power source, and the control device in the gas laser oscillator shown in FIG. FIG. 4 is a time chart for explaining an example of a laser output mode.

  As shown in FIG. 3, the discharge electrodes 2a and 2b and the discharge electrodes 3a and 3b are connected to independent high-frequency power sources 20a and 20b, respectively. The high frequency power supplies 20a and 20b operate independently under the control of the control device 21, respectively. That is, the high frequency power source 20a supplies high frequency power to the discharge electrodes 2a and 2b in accordance with the control signal 22a from the control device 21. The high frequency power source 20b supplies high frequency power to the discharge electrodes 3a and 3b in accordance with a control signal 22b from the control device 21.

  Specifically, for example, as shown in FIG. 4, the high frequency power supplies 20a and 20b receive power from the control signals 22a and 22b in response to a command for the power input time width and power density. I do.

  Thereby, the first electrode pair 2 (discharge electrodes 2a and 2b) and the second electrode pair 3 (discharge electrodes 3a and 3b) form excitation discharges 24a and 24b with independent high-frequency power, respectively. 1 optical resonator 25a (partial reflection mirror (PR) 4, transverse mode limiting aperture 8 and total reflection mirror (TR) 6), and second optical resonator 25b (partial reflection mirror (PR) 5, transverse mode) In the limiting aperture 9 and the total reflection mirror (TR) 7), laser oscillations with independent contents are performed, and laser beams with independent contents from the partial reflection mirrors (PR) 4 and 5 to the outside of the vacuum vessel 1 respectively. 26a and 26b are output.

  In this case, in the gas circulation supply system, the shape of the gas duct 12 is optimized so that the discharge distributions of the excitation discharges 24a and 24b are the same as much as possible, that is, the gas flow distribution is not different. Specifically, in particular, the pressure loss of the gas flow flowing between the first electrode pair 2 (discharge electrodes 2a, 2b) and between the second electrode pair 3 (discharge electrodes 3a, 3b) is equalized. The gas supply port between the electrodes has a large opening shape so that the pressures of the gas flows 15 a and 15 b to be supplied are equal, and the gas passing through the electrodes 16 a and 16 b between the electrodes is taken into a return gas flow 16. The flow path has a smooth shape so that the loss does not increase and becomes a laminar flow.

  As described above, the first electrode pair 2 and the first optical resonator 25a, and the second electrode pair 3 and the second optical resonator 25b are configured as independent laser oscillation systems. ) The beam modes of the laser beams 26a and 26b can be made the same or different, and (2) the intensities of the laser beams 26a and 26b are made almost the same or different. Is possible.

  (1) To make the beam modes of the laser beams 26a and 26b the same, the first optical resonator 25a and the second optical resonator 25b may be configured with the same specification specifications. In this case, there is a variation due to the shape of the first electrode pair 2 or the second electrode pair 3 or a variation due to the gas flow between the discharge distributions of the excitation discharges 24a and 24b. When the beam modes of the laser beams 26a and 26b are different to the extent that they affect the processing quality when used as a laser light source of the processing system, the laser beam can be adjusted by finely adjusting the transverse mode limiting apertures 8 and 9. It is possible to make each beam mode of 26a, 26b the same.

  Accordingly, when the beam modes of the laser beams 26a and 26b are made different, the first optical resonator 25a and the second optical resonator 25b may be configured with different specification specifications. This makes it possible to select a beam mode suitable for different processing when used as a laser light source of a laser processing system. The beam mode can be changed by changing the aperture diameter or changing the curvature of the partial reflection mirror or the total reflection mirror. In general, the smaller the aperture and the larger the curvature of the reflecting mirror (that is, flattening), the smaller the order of the beam mode.

  Specifically, the settings of the first optical resonator 25a and the second optical resonator 25b are made different, and the order of the beam mode in the first optical resonator 25a is changed in the second optical resonator 25b. When the laser beam is used as a laser light source in a laser processing system in a state higher than the first order, a workpiece that can obtain better processing quality when the mode order is higher is irradiated with the laser beam 26a, and the mode order is lower and the light condensing property. It is possible to selectively use a workpiece that can obtain a good processing quality when it is better, such as irradiating a laser beam 26b.

  (2) Further, in order to make the intensities of the laser beams 26a and 26b substantially the same, the input power amounts of the high-frequency power sources 20a and 20b are related to each other so that the excitation discharges 24a and 24b maintain substantially the same intensity. Can be set. In this case, the pumping efficiency varies depending on the variation in load applied between the electrodes of the first electrode pair 2 and the second electrode pair 3, or the first optical resonator 25a and the second optical resonator 25b. When the optical pumping efficiency varies depending on the variation of the laser beam, the final laser output can be made substantially the same by finely adjusting the high-frequency power sources 20a and 20b.

  Therefore, in order to make each intensity | strength of laser beam 26a, 26b different, what is necessary is just to set each input electric energy of high frequency power supply 20a, 20b mutually independently so that excitation discharge 24a, 24b may maintain different intensity | strength. Thereby, when used as a laser light source of a laser processing system, it is possible to select a laser output suitable for different processing.

  Specifically, for example, by making the input power amount of the high-frequency power source 20a larger than the input power amount of the high-frequency power source 20b, the laser beam 26a is irradiated for processing that requires a large laser output, thereby reducing the laser output. For better processing, it is possible to selectively use the laser beam 26b.

  As described above, according to the first embodiment, in each optical resonance region in two independent optical resonators, the excitation discharge is always kept in a state where high oscillation efficiency can be obtained, and each is independent. The two laser beams to be output can be generated with substantially the same beam quality or arbitrary beam quality, so that two stable and high laser outputs can be obtained and the two lasers generated A multi-output three-axis orthogonal gas laser oscillator capable of adjusting the beam quality to a desired quality can be provided.

  In addition, the thermal load on the optical component can be reduced as compared with a conventional three-axis orthogonal gas laser oscillator that achieves high output with a single laser beam output, thereby improving stability or reliability. Can increase the life expectancy.

  In addition, since two stable high laser outputs can be obtained without particularly increasing the size of each laser oscillation system as in the conventional improvement examples 1 and 2, a relatively compact configuration can be achieved. In addition, it is possible to obtain a multi-output three-axis orthogonal gas laser oscillator with excellent cost performance.

Embodiment 2. FIG.
5 and 6 are conceptual diagrams showing a configuration of a three-axis orthogonal type gas laser oscillator according to Embodiment 2 of the present invention. 5 is a cross-sectional view along the optical axis direction, and FIG. 6 is a cross-sectional view along the direction perpendicular to the optical axis.

  As shown in FIGS. 5 and 6, in the three-axis orthogonal type gas laser oscillator according to the second embodiment, the discharge electrode 2 a, which is the first electrode pair 2, is arranged on the upper side in the height direction in the vacuum vessel 1. 2b and the first optical resonator 25a are arranged, and the discharge electrodes 3a and 3b and the second optical resonator 25b as the second electrode pair 3 are arranged on the lower side, and the blower 10 and the first optical resonator 25a are arranged between them. The heat exchanger 11 is disposed, and a gas duct 27 is provided between the blower 10 and the discharge gaps of the discharge electrodes 2a and 2b and the discharge electrodes 3a and 3b.

  The gas flow path by the gas duct 27 includes the flow path of the gas flows 28a and 29a returning from the blower 10 to the blower 10 via the first electrode pair 2 and the blower 10 from the blower 10 via the second electrode pair 2. It consists of the flow path of gas flow 28b, 29b which returns to.

  The same operational effects as those of the first embodiment can also be obtained by such an arrangement according to the second embodiment. In addition, the two electrode pairs can be completely independent both electrically and mechanically. However, in order to ensure the insulation distance between the discharge electrode 2b and the discharge electrode 3a and the blower 10 and the heat exchanger 11, compared with the arrangement shown in the first embodiment, the overall height is larger. There is a possibility of becoming.

  In the first and second embodiments, the output directions of the two laser beams are the same, but they may be opposite to each other. This can be easily realized by reversing the positional relationship between the partial reflection mirror and the total reflection mirror in the two optical resonators.

  In the first and second embodiments, the configuration in which two laser beams are output has been described. However, a configuration in which three or more laser outputs are obtained can also be realized based on the same idea.

Embodiment 3 FIG.
FIG. 7 is a block diagram showing the configuration of a multi-axis laser processing system according to Embodiment 3 of the present invention. The laser processing system shown in FIG. 7 uses the three-axis orthogonal gas laser oscillator 30 shown in the first or second embodiment as a laser light source, and uses the laser beams 36a and 36b emitted from the three-axis orthogonal gas laser oscillator 30 as one work table. An optical system 33a, 33b for transmitting to a work 32 placed on the head 31 and a control device 34 for controlling each of these elements are provided.

  The operation will be described. The two independent laser oscillation systems included in the three-axis orthogonal gas laser oscillator 30 perform independent laser oscillation under the control of independent laser oscillation conditions (timing, intensity, and time width) from the controller 34. Laser beams 36a and 36b are generated. The laser beam 36a is output to the optical system 33a, and the laser beam 36b is output to the optical system 33b.

  The optical system 33 a shapes the incident laser beam 36 a under the control of the control device 34, and generates a laser beam 37 a that condenses and irradiates the workpiece 32 placed on the work table 31 by two-dimensional scanning. .

  Similarly, the optical system 33b shapes the incident laser beam 46b under the control of the control device 34, and two-dimensionally scans the laser beam 37b that condenses and irradiates the workpiece 32 placed on the work table 31. Is generated.

  According to the third embodiment, one gas laser oscillator (three axes) capable of outputting the two laser beams shown in the first and second embodiments to a laser light source of a laser processing system that performs simultaneous processing in two axes. Since an orthogonal gas laser oscillator) is used, the configuration of the optical system provided between the gas laser oscillator and the workpiece is simplified. That is, the system can be configured relatively compactly, and a laser processing system with excellent cost performance such as easy maintenance can be obtained.

  In addition, the heat load on the optical component can be reduced compared to the optical system that transmits a single high-intensity laser beam as in the conventional example, so that the reliability of the optical system is improved and the life is increased. Can be planned.

  As described in the first embodiment, the two laser beams output from the gas laser oscillator can be controlled independently. Therefore, when two laser beams are irradiated to one workpiece, each laser beam is emitted. Even when the beam irradiation patterns are different, desired biaxial machining can be performed simultaneously without using the energy division method or the time division method. Therefore, good processing quality can be obtained, and productivity can be improved to the maximum.

  In the third embodiment, the case where two laser beams are irradiated onto one workpiece has been described. However, even if the number of laser beams and the number of workpieces are different, for example, two laser beams are irradiated with two laser beams. Even in the case where two workpieces are processed with a total of four beams, the desired biaxial machining can be performed simultaneously on each workpiece without using the energy division method or the time division method. In addition, good processing quality can be obtained, and productivity can be improved to the maximum.

  As described above, the three-axis orthogonal gas laser oscillator according to the present invention generates two or more independent laser beams with desired outputs in a relatively compact configuration, and the quality of each laser beam is improved. It is useful for generating by individually adjusting, and is particularly suitable for a laser light source of a laser processing system that performs multi-axis simultaneous processing.

  Moreover, the laser processing system according to the present invention is useful for performing multi-axis simultaneous processing with good processing quality and high productivity.

1 is a cross-sectional view along the optical axis direction showing the configuration of a three-axis orthogonal type gas laser oscillator according to Embodiment 1 of the present invention; FIG. It is sectional drawing along the direction perpendicular | vertical to the optical axis of the gas laser oscillator shown in FIG. It is a figure explaining the relationship between two pairs of discharge electrodes in the gas laser oscillator shown in FIG. 1, a high frequency power supply, and a control apparatus. It is a time chart explaining an example of the laser output aspect of the gas laser oscillator shown in FIG. It is sectional drawing along the optical axis direction which shows the structure of the 3-axis orthogonal type | mold gas laser oscillator by Embodiment 2 of this invention. FIG. 6 is a cross-sectional view along a direction perpendicular to the optical axis of the gas laser oscillator shown in FIG. 5. It is a block diagram which shows the structure of the laser processing system by Embodiment 3 of this invention. It is a block diagram which shows the structural example of the conventional laser processing system. It is sectional drawing along the optical axis direction which shows the structural example of the conventional triaxial orthogonal type gas laser oscillator. FIG. 10 is a cross-sectional view taken along a direction perpendicular to the optical axis of the three-axis orthogonal gas laser oscillator shown in FIG. 9. FIG. 10 is a cross-sectional view along the optical axis direction showing an improved example (part 1) of the three-axis orthogonal gas laser oscillator shown in FIG. 9. FIG. 12 is a sectional view taken along a direction perpendicular to the optical axis of the three-axis orthogonal gas laser oscillator shown in FIG. 11. FIG. 10 is a cross-sectional view along the optical axis direction showing an improved example (part 2) of the three-axis orthogonal gas laser oscillator shown in FIG. 9. It is sectional drawing along the direction perpendicular | vertical to the optical axis of the triaxial orthogonal gas laser oscillator shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vacuum container 2 1st electrode pair 2
2a, 2b Discharge electrode 3 Second electrode pair 3a, 3b Discharge electrode 4, 5 Partial reflector (PR)
6,7 Total reflector (TR)
8, 9 Aperture for restricting transverse mode 10 Blower 11 Heat exchanger 12 Gas duct 15, 15a, 15b, 16a, 16b, 16 Gas flow 20a, 20b High frequency power supply 21 Controller 21a, 21b Control signal 24a, 24b Excitation discharge 25a First Optical resonator 25b Second optical resonator 26a, 26b Laser beam 30 3-axis orthogonal gas laser oscillator 31 Work table 32 Workpiece (workpiece)
33a, 33b Optical system 34 Controller 36a, 36b, 37a, 37b Laser beam

Claims (7)

In one container filled with a mixed gas that is a laser medium,
A discharge electrode pair that forms an excitation discharge according to input power in a discharge gap, which is a gap between two plate electrodes having a major axis and a minor axis, and an opposing arrangement across the major axis direction of the discharge electrode pair And at least two independent laser oscillation systems each including an optical resonator that performs laser oscillation based on the excitation discharge by the total reflection mirror and the partial reflection mirror and emits a laser beam to the outside from the partial reflection mirror, and All the laser oscillation systems are arranged side by side in the opposing arrangement direction of the discharge electrode pair,
Gas circulation supply means for circulating the mixed gas supplied to the discharge gap in each of the independent laser oscillation systems while cooling as a gas flow passing from one end side to the other end side in the minor axis direction is disposed. A gas laser oscillator characterized by comprising:   The optical resonator in each of the independent laser oscillation systems includes a transverse mode limiting aperture that defines a laser oscillation mode so that the laser beams generated in each of the independent laser oscillation systems have almost the same beam quality or different desired ones. The gas laser oscillator according to claim 1, wherein the total reflection mirror, the partial reflection mirror, and the transverse mode limiting aperture are selected so that the beam quality is as follows.   The control means for controlling each oscillation operation in the independent laser oscillation system controls the power application timing, the power input time width, and the input power amount to the discharge electrode pair independently of each other. Item 3. The gas laser oscillator according to Item 1 or 2. The gas laser oscillator according to claim 1, which is a laser light source that emits a plurality of laser beams;
An optical system for two-dimensionally scanning each of a plurality of laser beams emitted from the gas laser oscillator to focus and irradiate one or more workpieces;
A laser processing system comprising: control means for controlling each oscillation operation mode of a plurality of independent laser oscillation systems incorporated in the gas laser oscillator and a two-dimensional scanning mode for each laser beam in the optical system. .   Each optical resonator in a plurality of independent laser oscillation systems built in the gas laser oscillator is capable of emitting a laser beam having a beam quality according to the processing characteristics of the workpiece. The laser processing system according to claim 4, wherein the laser processing system is configured by selecting a reflector and a transverse mode limiting aperture that defines a laser oscillation mode.   The control means is configured such that power supply timing, power input time width and input power amount to each discharge electrode pair in a plurality of independent laser oscillation systems built in the gas laser oscillator are independent from each other according to the processing characteristics of the workpiece. The laser processing system according to claim 4 or 5, wherein   The blower and the heat exchanger in the gas circulation supply means are arranged on one end side in the opposed arrangement direction of the discharge electrode pair, or two or more of the two or more arranged in the opposed arrangement direction of the discharge electrode pair The gas laser oscillator according to claim 1, wherein the gas laser oscillator is disposed between two discharge electrode pairs in the discharge electrode pair.

Images