JPH04305987A - Gas laser oscillator - Google Patents

Abstract

PURPOSE:To make smooth the flow of gas laser to be supplied to discharge electrodes by providing a compressing flow path in the gas flow inlet port side of the laser gas flow path formed between a pair of discharge electrodes of discharger and providing an expanding flow path in the gas flow exhaust port side. CONSTITUTION:Circuit boards 14, 15 which are also used as the mounting boards are respectively provided opposed with each other in the sides of electrode supporting boards 11, 12 provided opposed with each other and a laser gas flow path 16 is formed between the pairing circuit boards 14, 15. A bell mouth type expanding flow path 18 is formed in the gas inlet port side of this flow path 16 in order to smoothly supply the laser gas. The flow path extending to the expanding flow path 18 from the compressing flow path 17 of laser gas through the flow path 16 between the circuit boards 14, 15 forms a part of a laser gas circulating flow path 3 and forms continuous and smooth flow path structure. An inclination angle alpha of the expanding flow path 18 is set, for example, to about 8 to 13 degrees.

Description

[Detailed description of the invention]

[Purpose of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas laser oscillation device, and more particularly to a gas laser oscillation device with an improved laser gas flow path in a discharge section.

0002

[Prior Art] Conventionally, as a gas laser oscillation device, as shown in FIG.
There is one configured as shown below. The gas laser oscillation device has a main body casing 1 as a gas laser, and this main body casing 1 accommodates a cylindrical frame 2 in the center. Laser gas is sealed along the periphery of this frame 2, and a wind tunnel 3 in which the laser gas is circulated is formed as a laser gas circulation flow path. A pair of bases 4, 4 is provided with an interval between the inner surface of the main body casing 1 and the frame 2 forming the wind tunnel 3, and a semi-cylindrical discharge electrode is provided on these bases 4, 4. 5, 5 are arranged facing each other with a gap in between. These discharge electrodes 5, 5 are connected to a high voltage power source (not shown). The wind tunnel 3 is also provided with a cooler 6 and a blower 7 for circulating laser gas, and the blower 7 is driven by a drive motor 8.

[0003] When the blower 7 is driven by the drive motor 8, the laser gas in the wind tunnel 3 is circulated in the direction of arrow A in the figure and is supplied between the discharge electrodes 5, 5, passing between them. When the laser gas passes between the discharge electrodes 5, 5, a discharge voltage is applied to the laser gas and the laser gas is excited.

When the energy of the excited laser gas drops to a lower energy level, a laser beam is output, and this laser beam is taken out to the outside as a laser beam perpendicular to the laser gas circulation flow path (wind tunnel 3). It has become. On the other hand, the laser gas generated by laser oscillation retains most of the energy obtained by the discharge as heat, but is cooled by heat exchange in the cooler 6, returned to the blower 7, and supplied to the discharge electrodes 5, 5 side. Ru.

[0005]

[Problems to be Solved by the Invention] According to the configuration of the conventional gas laser oscillation device, the discharge electrodes 5, 5 to which the laser gas is supplied are provided protruding into the laser gas circulation flow path. Circulation flow path resistance to the laser gas flowing through the gap increases. The increase in flow path resistance requires the blower 7 to have a large blowing capacity in order to supply a predetermined laser gas, which increases the output of the drive motor 8, which in turn reduces the efficiency of the entire gas laser oscillation device. become.

Furthermore, the fact that the discharge electrodes 5, 5 protrude into the laser gas circulation flow path causes disturbances in the flow velocity distribution of the laser gas, which makes the discharge at the discharge electrodes 5, 5 less stable, and There was a possibility that laser oscillation could not be obtained.

The present invention has been made in consideration of the above-mentioned circumstances, and provides a gas laser that can smooth the flow of laser gas supplied to the discharge electrode, improve operating efficiency, and oscillate a stable laser beam. The purpose is to provide an oscillation device. [Structure of the invention]

[0008]

[Means for Solving the Problems] In order to solve the above-mentioned problems, the gas laser oscillation device according to the present invention includes a gas laser body in which a laser gas is sealed, a blowing means for circulating the laser gas inside the gas laser body, and a circulating means for circulating the laser gas inside the gas laser body. and a discharge section that forms a part of the circulation flow path for the laser gas and excites the laser gas being circulated, and the discharge section is connected to the substrate, leaving a portion where the discharge occurs. a pair of discharge electrodes embedded in the
The laser gas flow path formed between the discharge electrodes includes a contraction path provided on the gas inlet side, and an enlarged path provided on the laser gas outlet side from the discharge electrodes.

[0009]

[Operation] In the gas laser oscillation device of the present invention, a contracting channel is provided on the gas inlet side of the laser gas channel formed between a pair of discharge electrodes in the discharge section, and an expanding channel is provided on the gas outlet side. Because of the continuous and smooth flow path structure, the laser gas contracted in the contracted flow path is smoothly guided to the discharge electrode, and the laser gas flows between the pair of discharge electrodes at a high speed without any variation in the velocity distribution. The temperature rise of the laser gas due to flow and discharge is small, and deterioration of the laser gas can be reduced, and a stable laser beam can be oscillated while improving operational efficiency.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a gas laser oscillation device according to the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a side sectional view showing a preferred embodiment of a gas laser oscillation device according to the present invention. In explaining this gas laser oscillation device, the same parts as those of the conventional gas laser oscillation device shown in FIG.

The gas laser oscillation device shown in FIG. 1 has an improved discharge section 10 housed in a main body casing 1 serving as a gas laser main body. The discharge section 10 is provided with electrode support plates 11 and 12 that are arranged opposite to each other with a laser gas circulation path (wind tunnel) 3 in between. One electrode support plate 11 has the function of a lid covering the top opening of the main body casing 10, and this electrode support plate 11 is fixed with fixing means such as bolts via an O-ring 13 as a sealing means. Further, the other electrode support plate 12 is provided at the top of the cylindrical frame 2, and both electrode support plates 11 and 12 are opposed to each other, for example, with an interval in the vertical direction.

On the other hand, substrates (bases) 14 and 15, which also serve as mounting stands, are attached to opposing surfaces of the electrode support plates 11 and 12, respectively, and the flow of laser gas is prevented between the pair of substrates 14 and 15. A channel 16 is formed. A bellmouth-shaped contraction channel 17 that smoothly supplies the laser gas is formed on the gas inlet side of the channel 16, and a diffuser-shaped enlarged channel 18 is formed on the gas outlet side. The passage from the laser gas contraction passage 17 to the enlarged passage 18 via the passage 16 between the bases 14 and 15 constitutes a part of the laser gas circulation passage 3 and has a continuous smooth passage structure.

The upstream guide blocks 20 and 21 forming the contracted flow path 17 have, for example, a 1/4 arc shape and are connected to the base 14.
, 15 is installed adjacent to the upstream side of each electrode support plate 11.
, 12. Further, the downstream guide blocks 22 and 23 forming the enlarged path 18 are installed adjacent to the downstream sides of the bases 14 and 15, and are fixed to the respective electrode support plates 11 and 12 in the same manner as the upstream guide blocks 20 and 21. be done. The inclination angle α of the enlarged path 18 is set, for example, to about 8° to 13°.

Further, recesses 25 and 26 extending in the width direction of the laser gas flow path 16 are formed on the upstream guide blocks 20 and 21 of the pair of bases 14 and 15.
, 26 have a discharge electrode 2 having a curved shape such as a semi-cylindrical shape.
7 and 28 are installed opposite each other in a pair. discharge electrode 27,
The surface of 28 (the part where discharge occurs) is the base 14, 1
It is formed almost flush with the surface of 5.

In the gas laser oscillation device configured as described above, when the blower 7 as the blower means is driven by the drive motor 8, the laser gas inside the main body casing 10, which is the gas laser main body, is circulated in the direction of the arrow A in the figure and is contracted. is supplied from the flow path 17 to the flow path 16 between the discharge electrodes 27 and 28,
When passing through this flow path 16, a discharge is generated from a pair of discharge electrodes and excited. The excited energy is then extracted as a laser beam to the outside from a direction perpendicular to the laser gas circulation path 3. On the other hand, the laser gas that has been oscillated is sent to the cooler 6 through the expansion path 18, where it is cooled by heat exchange, and returned to the blower 7, where it is sent to the discharge electrode 2.
It is now supplied to the 7 and 28 sides.

In this way, as shown in FIG. 2, after the laser gas flows into the contraction channel 17, the guide block 2
0 and 21 to reach the discharge electrodes 27 and 28, the thickness t of the velocity boundary layer a formed on the guide blocks 20 and 21 by the laser gas flowing into the contraction channel 17 is smaller than that of the conventional method. It is thinner than that of .

Since the velocity distribution of the laser gas in the velocity boundary layer a is slower than the flow velocity in the velocity boundary layer a, the velocity boundary layer a
The thinner the thickness, the faster the speed of the laser gas between the discharge electrodes 27 and 28. Therefore, the temperature rise due to the discharge of the laser gas between the discharge electrodes 27 and 28 is reduced, the discharge is stabilized, the oscillation of the laser beam is stabilized, and the machining by the laser beam is of higher quality.

In this gas laser oscillation device, the bellmouth-shaped upstream guide blocks 20 and 21 forming the contracted flow path 17 and the discharge electrodes 27 and 28 are installed close to each other, so that the discharge after the laser gas contracted flow is prevented. The creepage distance to the electrodes 27, 28 is shortened, and the distance from the contraction part to the discharge electrodes 27, 28 is reduced.
The thickness of the velocity boundary layer of the laser gas that develops by 28 is suppressed. Therefore, the velocity loss of the laser gas flowing through the contracted flow path 17 between the discharge electrodes 27 and 28 is reduced, the laser gas can flow smoothly, the temperature rise between the discharge electrodes 27 and 28 due to discharge is reduced, and the discharge is stabilized. Therefore, the oscillation of the laser beam can be stabilized. Next, other embodiments of the gas laser oscillation device are shown in FIGS. 3 to 5.
Explain with reference to.

The gas laser oscillation device shown in this example differs from the gas laser oscillation device shown in FIGS. 1 and 2 only in the configuration of the discharge section, and the same parts are given the same reference numerals and explanations are omitted. do.

[0021] This gas laser oscillation device has a discharge section 10A.
A laser gas flow path 16 is formed between the bases 14 and 15 as mounting bases provided opposite to the electrode support plates 11 and 12, while upstream guide blocks 20A and 21A are provided on the upstream side of the bases 14 and 15. On the downstream side thereof, downstream guide blocks 22 and 23 are arranged adjacent to each other and facing each other. A pair of upstream guide blocks 20A,
21A, the laser gas is passed through the flow path 1 between the bases 14 and 15.
A bellmouth-shaped contraction channel 17A is formed to guide the base 1 to the base 1 between the downstream guide blocks 22 and 23.
A diffuser-shaped enlarged path 18 is formed to guide the laser gas flowing out from the flow path 16 between the holes 4 and 15.

Further, recesses 25A and 26A are formed in the center portions of the bases 14 and 15, and extend in the width direction of the laser gas circulation flow path. Electrodes 27 and 28 are buried. For example, the discharge electrodes 27 and 28 are arranged facing each other with an interval between the upper and lower sides, while the surfaces on which discharge occurs are the bases 14 and 15.
It is constructed almost flush with the surface of.

[0023] Thus, the blower 7 is driven by the drive motor 8.
When the laser gas circulation channel 3 is driven, the laser gas in the laser gas circulation channel 3 is circulated in the direction of the arrow A in the figure, and is supplied from the contraction channel 17A to the channel 16 between the discharge electrodes 27 and 28, and while passing through this channel 16, the laser gas is is excited by the discharge from the discharge electrodes 27 and 28. The excited energy is then extracted as a laser beam to the outside in a direction perpendicular to the laser gas flow path 16.

On the other hand, the laser gas generated by laser oscillation retains most of the energy obtained by the discharge as heat, but is cooled by heat exchange in the cooler 6, returned to the blower 7, and then transferred to the discharge electrodes 27, 28. supplied in between.

[0025] In this gas laser oscillation device, the contracted flow path 17A formed in the discharge section 10A, the discharge electrodes 27, 2
8 and the enlarged channel 18 are formed in a continuous and smooth channel structure, the channels 17A and 18 in the discharge section 10A,
The laser gas flows smoothly through the gas laser oscillators 16 and 18, and the effect is almost the same as that of the gas laser oscillation device shown in FIGS. 1 and 2. However, the contraction channel 1 on the inlet side of the discharge electrodes 27 and 28
Upstream guide blocks 20A, 21 forming 7A
Since the distance from A to the discharge electrodes 27 and 28 after contraction is longer than that shown in FIGS. 1 and 2, velocity boundary layers b develop on the surfaces of the upstream guide blocks 20A and 21A, as shown in FIG. Therefore, at the installation positions of the discharge electrodes 27 and 28, there is a possibility that the velocity distribution of the laser gas flow velocity near the discharge electrodes 27 and 28 is slightly disturbed and becomes slow.

[0026]

As explained above, in the gas laser oscillation device according to the present invention, a contracted flow path is provided on the gas inlet side of the laser gas flow path formed between a pair of discharge electrodes in the discharge section, and the gas Since an expanded channel is provided on the outlet side and a continuous smooth flow channel structure is created, the laser gas contracted in the contracted channel is smoothly guided to the discharge electrode, and the velocity distribution of the laser gas is adjusted between the pair of discharge electrodes. without any variation,
The laser gas flows at a high speed, and the thickness of the velocity boundary layer that develops from the contraction part to the discharge electrode is suppressed, reducing velocity loss, allowing the laser gas to flow smoothly, and increasing the temperature of the laser gas due to discharge. can be reduced. Therefore, discharge is stabilized and laser oscillation is stabilized.

Furthermore, since the pressure loss of the laser gas can be reduced, the output of the blower and the blower drive motor can be reduced, so that the overall efficiency of the laser oscillation device can be increased.

[Brief explanation of drawings]

FIG. 1 is a side sectional view showing an embodiment of a gas laser oscillation device according to the present invention.

FIG. 2 is an enlarged configuration diagram showing a discharge section of the gas laser oscillation device shown in FIG. 1;

FIG. 3 is a side sectional view showing another embodiment of the gas laser oscillation device according to the present invention.

FIG. 4 is a sectional view taken along line XX in FIG. 3;

FIG. 5 is a configuration diagram showing an enlarged discharge section of the gas laser oscillation device shown in FIG. 3;

FIG. 6 is a side sectional view showing a conventional gas laser oscillation device.

[Explanation of symbols]

1 Main body casing (gas laser main body) 2 Frame 3 Wind tunnel (laser gas circulation flow path) 4 Base 6 Cooler (cooling means) 7 Air blower (air blowing means) 8 Drive motor 10, 10A Discharge section 11, 12 Electrode support board 14, 15 Base 16 Laser gas channel 17 17A Contraction channel 18 Expansion channel 20, 20A, 21, 21A Upstream guide block 22, 23 Downstream guide block 25, 25A, 26, 26A Recess 27, 28 Discharge electrode

Claims (1)

[Claims] 1. A gas laser main body in which a laser gas is sealed, a blowing means for circulating the laser gas inside the gas laser main body, a cooling means for cooling the circulated laser gas, and forming a part of a circulation flow path for the laser gas. , and a discharge part that excites the circulated laser gas,
The discharge section includes a pair of discharge electrodes buried in the base leaving a portion where discharge occurs, and a contracted flow path provided on the gas inlet side of the laser gas flow path formed between the discharge electrodes.
A gas laser oscillation device comprising: an enlarged path provided on the laser gas outlet side from the discharge electrode.