Carbon dioxide gas laser device

Abstract

To provide a carbon dioxide gas laser device that operates with an excitation gas that is a mixture of carbon dioxide gas supplied from a gas cylinder containing only carbon dioxide gas and nitrogen gas contained in the taken-in atmosphere in order to significantly reduce running costs.SOLUTION: A carbon dioxide gas laser device according to the present disclosure includes: a discharge tube containing an excited gas; a first air supply valve that is disposed at a first position of the discharge tube and adjusts an amount of carbon dioxide gas, which is a first main component of the excitation gas, supplied into the discharge tube; a second air supply valve that is arranged at a second position of the discharge tube and adjusts an amount of air containing nitrogen gas, which is a second main component of the excitation gas, supplied into the discharge tube; and an exhaust valve that adjusts an amount of the excited gas exhausted from the discharge tube.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a gas flow type carbon dioxide laser device. [Background technology]

[0002] Carbon dioxide lasers are gas lasers capable of stably outputting high-power laser light and are the most widely used laser in industry. They are used widely not only for cutting, drilling, welding, and surface modification of metals and non-metals, but also in medical settings such as medical and cosmetic fields.

[0003] High-output carbon dioxide lasers in the kW class generally use a "gas flow type" laser oscillator, in which a mixture of carbon dioxide, nitrogen, and helium gases is supplied from a gas cylinder to a discharge tube as excitation gas, while small and medium-output carbon dioxide lasers below the several hundred watt level generally use a "sealed type" laser oscillator, in which this mixed gas is sealed inside the discharge tube.

[0004] 4 is an example of the overall configuration of a conventional gas flow type carbon dioxide gas laser device 21. In the carbon dioxide gas laser device 21, an excitation gas is sealed in a discharge tube 22 equipped with a total reflecting mirror 23-1 and a partial reflecting mirror 23-2 at both ends, and the excitation gas is excited by an electric discharge between a third electrode 24-1 and a fourth electrode 24-2 to generate laser light.

[0005] The excitation gas is a mixed gas whose main components are carbon dioxide gas, nitrogen gas, and helium gas, and is supplied from a gas cylinder 27 through a needle valve 25 into the discharge tube 22 .

[0006] Nitrogen gas contained in the excitation gas is essential for efficient output of laser light, and sufficient laser output cannot be obtained without nitrogen gas. On the other hand, helium gas has a cooling effect and has the effect of suppressing the temperature rise of the excitation gas and increasing the laser output, but if some restrictions on the laser output are acceptable, it is possible to obtain a sufficiently practical laser output even if the excitation gas does not contain helium gas.

[0007] In the conventional carbon dioxide laser device 21, the excitation gas stored in the gas cylinder 27 is supplied into the discharge tube 22 via the needle valve 25, and then exhausted to the outside of the discharge tube 22 via the vacuum pump (exhaust pump) 29, and is not recovered. Most of the excitation gas is helium gas. For this reason, the conventional carbon dioxide laser device 21 had to consume a large amount of helium gas when it operated. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Publication No. 60-113491 [Patent Document 2] Japanese Patent Application Publication No. 5-7033 Summary of the Invention [Problem to be solved by the invention]

[0009] Helium is a limited resource that is only produced in limited areas on Earth, and is an expensive gas. In the case of a gas flow type such as the carbon dioxide laser device 21, the excited gas exhausted from the discharge tube 22 is not recovered, and therefore a large amount of helium gas is consumed, resulting in extremely high running costs.

[0010] Therefore, an object of the present disclosure is to provide a carbon dioxide laser device that operates with an excitation gas that is a mixture of carbon dioxide gas supplied from a gas cylinder containing only carbon dioxide gas and nitrogen gas contained in the taken-in atmosphere, in order to significantly reduce running costs. [Means for solving the problem]

[0011] The carbon dioxide laser device of the present disclosure comprises: a discharge tube containing an excitation gas; a first supply valve arranged at a first position of the discharge tube and configured to adjust the amount of carbon dioxide gas, which is one of the main components of the excitation gas, supplied into the discharge tube; a second air supply valve arranged at a second position of the discharge tube and configured to adjust the amount of air containing nitrogen gas, which is the second main component of the excitation gas, supplied into the discharge tube; an exhaust valve for adjusting the amount of the excited gas exhausted from the discharge tube; The carbon dioxide laser device operates with an excitation gas mainly composed of the carbon dioxide gas supplied from the first air supply valve and nitrogen gas in the atmosphere supplied from the second air supply valve. Effect of the Invention

[0012] According to the present disclosure, it is possible to provide a carbon dioxide laser device that operates on an excitation gas that is a mixture of carbon dioxide gas supplied from a gas cylinder containing only carbon dioxide gas and nitrogen gas contained in the taken-in atmosphere, in order to significantly reduce running costs. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is a diagram showing an example of an overall configuration diagram of a first carbon dioxide gas laser apparatus according to a first embodiment of the present disclosure. [Diagram 2] FIG. 2 is a diagram showing an example of the relative positions of a first supply valve and a second supply valve of a first carbon dioxide gas laser apparatus according to a first embodiment of the present disclosure. [Diagram 3] FIG. 13 is a diagram showing an example of an overall configuration diagram of a second carbon dioxide gas laser apparatus according to a second embodiment of the present disclosure. [Figure 4] FIG. 1 is a diagram showing an example of an overall configuration diagram of a conventional carbon dioxide gas laser device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.

[0015] (First embodiment of the present disclosure) FIG. 1 shows an example of an overall configuration diagram of a first carbon dioxide gas laser device 1 according to a first embodiment of the present disclosure.

[0016] A first carbon dioxide laser device 1 according to a first embodiment of the present disclosure includes a discharge tube 2 made of a dielectric material such as glass, a total reflecting mirror 3-1 hermetically joined to one end of the discharge tube 2, a partial reflecting mirror 3-2 hermetically joined to the other end of the discharge tube 2, a first electrode 4-1 and a second electrode 4-2 as a pair of electrodes for discharging, a first air supply valve 5-1 that supplies carbon dioxide gas, which is one of the main components of the excitation gas in the discharge tube 2, into the discharge tube 2, a second air supply valve 5-2 that supplies air containing nitrogen gas, which is the second main component of the excitation gas in the discharge tube 2, into the discharge tube 2, and an exhaust block 9 that exhausts the excitation gas in the discharge tube 2.

[0017] An excitation gas consisting mainly of carbon dioxide gas and nitrogen is enclosed in the discharge tube 2. Carbon dioxide gas, which is one of the main components of the excitation gas, is supplied into the discharge tube 2 via a first air supply valve 5-1. Nitrogen gas, which is the second main component of the excitation gas, is supplied into the discharge tube 2 as part of the atmosphere via a second air supply valve 5-2.

[0018] A first electrode 4-1 and a second electrode 4-2 arranged on the discharge tube 2 are a pair of opposing discharge electrodes, and a discharge occurs between the first electrode 4-1 and the second electrode 4-2 by applying a voltage to the first electrode 4-1 from a power source (not shown). This discharge excites the excitation gas sealed in the discharge tube 2, and the resulting laser light is amplified by repeatedly reflecting between the total reflecting mirror 3-1 and the partial reflecting mirror 3-2, and is output to the outside from the partial reflecting mirror 3-2.

[0019] The first air supply valve 5-1 is disposed at a first position of the discharge tube 2, and is a valve for adjusting the flow rate of carbon dioxide gas supplied from a gas cylinder 7 connected via a first tube 6-1. The second air supply valve 5-2 is disposed at a second position of the discharge tube 2, and is a valve for adjusting the flow rate of air supplied from a filter 8-1 connected via a second tube 6-2. The first air supply valve 5-1 and the second air supply valve 5-2 may be opened and closed manually or automatically by using a control means.

[0020] The arrangement positions of the first air supply valve 5 - 1 and the second air supply valve 5 - 2 may be in any positional relationship with each other, but are preferably arranged at positions equidistant from the end points of the discharge tube 2 .

[0021] Fig. 2 shows an example of the relative positions of the first and second intake valves 5-1 and 5-2 of the first carbon dioxide laser device 1 according to the first embodiment of the present disclosure. If the portion leading from the first intake valve 5-1 to the discharge tube 2 is referred to as the first intake port 5-3 and the portion leading from the second intake valve 5-2 to the discharge tube 2 is referred to as the second intake port 5-4, Fig. 2 shows an example in which the distance d1 between the center point (black circle) of the first intake port 5-3 and one end point of the discharge tube 2 is equal to the distance d2 between the center point (black circle) of the second intake port 5-4 and one end point of the discharge tube 2.

[0022] As shown in Figure 2, in the first carbon dioxide laser device 1 according to the first embodiment of the present disclosure, a first air intake 5-3 through which carbon dioxide gas is supplied into the discharge tube 2 is opposed to a second air intake 5-4 through which nitrogen gas contained in the atmosphere is supplied into the discharge tube 2, thereby improving the mixability of the supplied carbon dioxide gas and nitrogen gas and making it possible to seal a more uniformly mixed excitation gas in the discharge tube 2.

[0023] Furthermore, a stirring means 10 may be provided between the first air inlet 5-3 and the second air inlet 5-4 to uniformly mix the carbon dioxide gas supplied from the first air inlet 5-3 and the nitrogen gas contained in the air supplied from the second air inlet 5-4. The stirring means 10 may be composed of, for example, an impeller and a motor for rotating the impeller. Figure 2 shows an example in which the stirring means 10 is provided between the first air inlet 5-3 and the second air inlet 5-4.

[0024] The gas cylinder 7 is a carbon dioxide gas cylinder that stores only carbon dioxide gas. The carbon dioxide gas stored in the gas cylinder 7 is supplied to the first air supply valve 5-1 via the first tube 6-1.

[0025] The filter 8-1 is connected to an opening 8-2 for taking in outside air into the discharge tube 2, and is a filter that removes impurities such as dust from the air that has flowed in from the opening 8-2.

[0026] The exhaust block 9 includes an exhaust valve 9-1 and a vacuum pump (exhaust pump) 9-2 that are disposed in the discharge tube 2. The exhaust block 9 opens the exhaust valve 9-1 and operates the vacuum pump (exhaust pump) 9-2 to exhaust the gas in the discharge tube 2 to the outside, thereby creating a negative pressure inside the discharge tube 2. Next, the flow of the excited gas will be described.

[0027] With the first air supply valve 5-1 and the second air supply valve 5-2 closed, the exhaust valve 9-1 is opened and the vacuum pump (exhaust pump) 9-2 is operated to evacuate the inside of the discharge tube 2. In this evacuated state, the first air supply valve 5-1 and the second air supply valve 5-2 are opened. As a result, a predetermined amount of carbon dioxide gas stored in the gas cylinder 7 and nitrogen gas contained in the atmosphere are supplied to the evacuated discharge tube 2, and they are mixed together and sealed in the discharge tube 2 as excited gas.

[0028] The mixture ratio of carbon dioxide gas and nitrogen gas contained in the excitation gas is set to a predetermined value. The opening amounts of the first air supply valve 5-1 and the second air supply valve 5-2 are adjusted so as to achieve this predetermined mixture ratio.

[0029] Furthermore, there may be multiple predetermined values ​​for the mixture ratio of carbon dioxide gas and nitrogen gas contained in the excitation gas. In the first carbon dioxide gas laser device 1 according to the first embodiment of the present disclosure, when changing the mixture ratio of carbon dioxide gas and nitrogen gas contained in the excitation gas, it is only necessary to adjust the amount of carbon dioxide gas supplied from the first intake valve 5-1 and the amount of nitrogen gas supplied from the second intake valve 5-2, and there is no need to replace the gas cylinder 7. Therefore, the first carbon dioxide gas laser device 1 according to the first embodiment of the present disclosure can very easily change the mixture ratio of carbon dioxide gas and nitrogen gas contained in the excitation gas.

[0030] When the required amount of excitation gas is sealed in the discharge tube 2, the first carbon dioxide laser device 1 applies voltage to the first electrode 4-1 from a power source not shown, causing a discharge between the first electrode 4-1 and the second electrode 4-2. This discharge excites the excitation gas and outputs a laser.

[0031] Thereafter, while discharge is occurring between the first electrode 4-1 and the second electrode 4-2, the excited gas, which has become hot due to excitation, is exhausted by the vacuum pump (exhaust pump) 9-2 of the exhaust block 9, and the excited gas that is insufficient due to exhaust from the exhaust block 9 is replaced by carbon dioxide gas being supplied from the first air supply valve 5-1 and nitrogen gas being supplied from the second air supply valve 5-2, thereby filling the discharge tube 2 with the excited gas. The amount of excited gas exhausted from the exhaust block 9 is adjusted by the opening amount of the exhaust valve 9-1 so that the inside of the discharge tube 2 becomes an appropriate negative pressure.

[0032] As described above, the first carbon dioxide laser device 1 according to the first embodiment of the present disclosure has some limitations in laser output because the excitation gas does not contain helium gas, but since the excitation gas is mainly composed of carbon dioxide gas supplied from a gas cylinder 7 storing only carbon dioxide gas and nitrogen gas contained in the taken-in atmosphere, it is possible to significantly reduce running costs.

[0033] (Second embodiment of the present disclosure) FIG. 3 shows an example of an overall configuration diagram of a second carbon dioxide gas laser device 11 according to a second embodiment of the present disclosure.

[0034] The second carbon dioxide laser device 11 is configured by adding a first flow meter 12-1 between the first air intake valve 5-1 and the gas cylinder 7, and adding a second flow meter 12-2 between the second air intake valve 5-2 and the opening 8-2 to the first carbon dioxide laser device 1.

[0035] By adding the first flow meter 12-1 and the second flow meter 12-2, it becomes possible to quantitatively grasp the amount of carbon dioxide gas flowing through the first air intake valve 5-1 and the amount of nitrogen gas flowing through the second air intake valve 5-2, making it possible to easily adjust the first air intake valve 5-1 to narrow the flow rate of carbon dioxide gas and the opening and closing amount of the second air intake valve 5-2 to narrow the flow rate of nitrogen gas.

[0036] For example, under the control of the control means, the first air supply valve 5-1 adjusts the amount of carbon dioxide gas supplied to the discharge tube 2 based on the flow rate measurement result of the first flow meter 12-1, and the second air supply valve 5-2 adjusts the amount of air containing nitrogen gas supplied to the discharge tube 2 based on the flow rate measurement result of the second flow meter 12-2.

[0037] Although some embodiments of the present disclosure have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the gist of the invention. [Explanation of symbols]

[0038] 1: The first carbon dioxide gas laser device 2:Discharge tube 3-1: Total reflection mirror 3-2: Partial reflector 4-1: First electrode 4-2: Second electrode 5-1: First air intake valve 5-2: Second air intake valve 5-3: First air intake 5-4: Second air intake 6-1: First tube 6-2: Second tube 7: Gas cylinder 8-1: Filter 8-2: Opening 9: Exhaust block 9-1: Exhaust valve 9-2: Vacuum pump (exhaust pump) 10: Stirring means 11: Second carbon dioxide gas laser device 12-1: First flow meter 12-2: Second flow meter 21: Conventional carbon dioxide gas laser device 22:Discharge tube 23-1: Total reflection mirror 23-2: Partial reflector 24-1: Third electrode 24-2: Fourth electrode 25: Needle valve 27: Gas Cylinder 29: Vacuum pump (exhaust pump)

Claims

1. a discharge tube containing an excitation gas; a first gas supply valve arranged at a first position of the discharge tube and configured to adjust the amount of carbon dioxide gas, which is one of the main components of the excitation gas, supplied into the discharge tube; a second air supply valve arranged at a second position of the discharge tube for adjusting the amount of air containing nitrogen gas, which is the second main component of the excitation gas, supplied into the discharge tube; an exhaust valve that adjusts the amount of the excited gas exhausted from the discharge tube, a carbon dioxide laser device that operates using an excitation gas whose main components are the carbon dioxide gas supplied from the first air supply valve and the nitrogen gas in the atmosphere supplied from the second air supply valve;

2. a first flow meter connected to the first air intake valve and measuring a flow rate of carbon dioxide gas to be supplied to the first air intake valve; and a second flow meter connected to the second air intake valve and measuring a flow rate of atmospheric air containing nitrogen gas to be supplied to the second air intake valve, the first gas supply valve adjusts the amount of carbon dioxide gas supplied into the discharge tube based on the flow rate measurement result of the first flow meter; 2. A carbon dioxide laser apparatus according to claim 1, wherein said second air supply valve adjusts the amount of atmospheric air containing nitrogen gas supplied into said discharge tube based on the flow rate measurement result of said second flow meter.

3. 2. A carbon dioxide laser apparatus according to claim 1, wherein the distance between the center of a first air inlet, through which carbon dioxide gas is supplied from the first air inlet valve to the discharge tube, and the end point of the discharge tube is equal to the distance between the center of a second air inlet, through which atmospheric air containing nitrogen gas is supplied from the second air inlet valve to the discharge tube, and the end point of the discharge tube.

4. 2. A carbon dioxide laser device as described in claim 1, wherein the mixing ratio of carbon dioxide gas and nitrogen gas contained in the excitation gas is determined by the amount of carbon dioxide gas supplied by the first air intake valve and the amount of air containing nitrogen gas supplied by the second air intake valve.

5. Further comprising a filter for removing impurities from the air, the second air intake valve adjusts the flow rate of the atmospheric air supplied through the filter.

2. The carbon dioxide laser device according to claim 1.

6. A laser oscillation method using a carbon dioxide laser device having a discharge tube containing an excitation gas and having first and second air inlets, and first and second electrodes arranged on the discharge tube, comprising: supplying carbon dioxide gas from the first gas supply port to the discharge tube; supplying atmospheric air from the second air supply port to the discharge tube; applying a voltage to the first and second electrodes such that a discharge occurs between the first and second electrodes; Laser oscillation method.

7. The discharge tube is further provided with an exhaust port, further comprising the step of evacuating the discharge tube through the exhaust port. The laser oscillation method according to claim 6.

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