JPS6022618Y2 - Gas flow type laser oscillator - Google Patents

Description

[Detailed description of the invention] (1) Technical field of the invention The invention relates to a laser oscillation tube with a gas flow set that uses carbon dioxide, nitrogen, helium, etc. as gaseous materials, and in particular stabilizes the gas pressure inside the laser oscillation tube. This invention relates to a gas flow laser oscillator that can reduce gas consumption.

(2) Prior Art and Problems Conventional laser oscillators of this type supply a gaseous material such as carbon dioxide gas from a gas supply section into the laser oscillation tube, and suck and exhaust the gaseous material with an exhaust pump. A certain amount of gas flow was formed inside the oscillator tube.

However, in this case, the suction pressure by the exhaust pump may pulsate in accordance with its rotation, and microscopic observation of the gas flow reveals that it pulsates in response to the pulsations in the suction pressure. .

Therefore, the pulsation propagates into the laser oscillation tube, causing the gas pressure to fluctuate and the laser output to fluctuate.

Further, since the gas flow rate of the entire gas flow system flows linearly in proportion to the suction pressure of the exhaust pump, the gas consumption increases in proportion to the suction pressure.

(3) Purpose of the invention The present invention was made to solve the above problems, and provides a gas flow laser oscillator that can stabilize the gas pressure inside the laser oscillation tube and reduce gas consumption. The purpose is to

(4) Structure of the invention and the above-mentioned object is, according to the invention, in a laser oscillator with a gas flow set including a gas supply section, a laser oscillation tube, and an exhaust pump for sucking and exhausting gas, from the laser oscillation tube to the exhaust pump. A distant relative is provided by providing a laser oscillator with a gas flow set, which is characterized in that a filter for restricting the gas flow is provided in the middle of the flow path.

(5) Embodiments of the invention Hereinafter, embodiments of the invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic diagram showing a gas flow laser oscillator according to the present invention.

The gas supply unit 1 stores carbon dioxide, which is a gas material for a gas laser, for example, and is made of a pressure-resistant cylinder with a capacity of about 1.
The carbon dioxide gas is stored at a pressure of 2.

The carbon dioxide gas from the gas supply section 1 is supplied by a regulator.
The pressure is reduced to a secondary pressure of 2 kp/c4, the flow rate is kept constant by the flow valve 2, and the flow flows into the laser oscillation tube 3.

Inside the laser oscillation tube 3, carbon dioxide gas generates plasma through discharge, and a pumping action is performed internally to amplify and feed back the plasma, thereby outputting a laser beam.

After contributing to laser oscillation in this way, carbon dioxide gas is
It is sucked in by an exhaust pump 4 such as a vacuum pump provided on the exhaust side of the laser oscillation tube 3, and is discharged into the atmosphere from an exhaust section 5.

Here, in the present invention, a filter 7 is provided in the middle of the flow paths 6, 6' from the laser oscillation tube 3 to the exhaust pump 4.

This filter 7 restricts the gas flow in the flow paths 6, 6' to form flow path resistance, and also generates a pressure difference between the gas pressure in front and behind the filter 7.
For example, a membrane filter with a pore diameter of 0.5 to 1.0 μm is used.

The filter 7 is selected by comprehensively determining the gas pressure inside the laser oscillation tube 3, the flow path length between the laser oscillation tube 3 and the exhaust pump 4, the exhaust capacity of the exhaust pump 4, the gas flow rate, etc. However, the filter is not limited to the above-mentioned membrane filter, but may be a tap-type filter, etc., as long as it generates a large pressure difference as a resistance in the flow path 6.degree. 6'.

By providing the filter 7 as described above, the pressure change in the gas flow system from the gas supply section 1 to the exhaust pump 4 becomes as shown in FIG. 2.

That is, the high-pressure carbon dioxide gas in the gas supply section 1 is reduced to a secondary pressure of 1 to 2 kg/Cft by the regulator, and flows into the laser oscillation tube 3 with the flow rate kept constant by the flow valve 2.

Inside the laser oscillation tube 3, the gas pressure P is constant.

The pressure of the gas flow exiting the laser oscillation tube 3 is slightly reduced due to the resistance of the flow path 6, and the gas pressure reaches P2 immediately before the filter 7.

Since the cross-sectional area of the flow path is greatly constricted at the position of the filter 7, the filter 7 acts as a large resistance to the flow path, and behind the filter 7, the gas pressure is greatly reduced to P3.

At this time, as a matter of course, the gas flow rate is also throttled and reduced.

The pressure of the gas flow passing through the filter 7 is slightly reduced due to the resistance of the flow path 6', and the gas pressure reaches P at the inlet of the exhaust pump 4.

Here, as mentioned above, a pressure difference of ΔP=P2-P3 occurs between the front and rear of the filter 7, so this pressure difference exerts a buffer effect, causing the exhaust pump 4 behind it to rotate. The propagation of pulsations caused by this is blocked.

Furthermore, the gas pressure P4 at the inlet of the exhaust pump 4 is Δ"("P
'4 P4), the gas flow rate of the entire gas flow system is reduced.

(6) Effects of the invention Since the present invention is constructed as described above, even if the suction pressure by the exhaust pump 4 pulsates according to its rotation, the buffer effect is exerted by the pressure difference before and after the filter 7, and the above-mentioned effect is achieved. The propagation of pulsations into the laser oscillation tube 3 can be blocked.

Therefore, the gas pressure within the laser oscillation tube 3 can be stabilized, and the laser output can be kept constant.

In addition, the gas flow is restricted by the filter 7 and the exhaust pump 4
Since the flow rate towards the gas flow system can be reduced, the gas consumption of the entire gas flow system can be reduced.

Furthermore, although an oil rotary vacuum pump is generally used as the exhaust pump 4, after the exhaust pump 4 is stopped after using the laser oscillator, oil mist inside the exhaust pump 4 flows backward through the channels 6 and 6'. The filter 7 can block the intrusion into the laser oscillation tube 3 by using the filter 7.

Therefore, it is possible to prevent the reflecting mirror for amplification and return from being contaminated with the oil mist.

[Brief explanation of drawings]

FIG. 1 is a schematic explanatory diagram showing a laser oscillator with a gas flow system according to the present invention, and FIG. 2 is a graph showing pressure changes in the gas flow system from the gas supply section to the exhaust pump. 1...Gas supply section, 2...Flow rate valve, 3
... Laser oscillation tube, 4 ... Exhaust pump, 5 ... Exhaust section, 6.6' ... Channel,
7...Filter.

Claims (1)

[Scope of utility model registration request] In a gas flow laser oscillator having a gas supply section, a laser oscillation tube, and an exhaust pump for sucking and exhausting gas,
A laser oscillation tube with a gas flow set, characterized in that a filter for restricting gas flow is provided in the middle of the flow path from the laser oscillation tube to the exhaust pump.