JPH06101601B2 - Gas laser device - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a gas laser device applied for processing or the like.

Configuration of Conventional Example and Problems Thereof In the conventional gas laser device, as shown in FIG.
The laser medium in the discharge tube 1 is circulated at high speed by connecting the roots blower 2 to the discharge medium, and the laser medium supply unit 7 partially replenishes the fresh laser medium while partially evacuating the discharge tube by using the vacuum pump 6. The inside of 1 is kept in a constant decompressed state, a constant gas flow is made to flow in the discharge tube 1 by the roots blower 2, and a DC power source E is applied to the electrodes 8 and 8'in the discharge tube 1 to cause discharge and laser oscillation is performed. .

By the way, the roots blower 2 has oil seals 3a on both sides of the rotor chamber 3 in order to maintain airtightness between the rotor chamber 3 for rotating the rotor 4 inside and the outside of the blower shaft for transmitting the driving force from the drive motor. An intervening oil sump gabox 5 is provided. In order to prevent oil from being mixed in the laser gas circulation system K of the gas laser device, the gas box 5 is decompressed by using the same vacuum pump 6 as the laser gas circulation system K or another vacuum pump.
A method is taken to prevent mixing of the oil mist from the oil seal 3a.

However, when oil mist is mixed in the laser gas circulation system K during normal steady operation, oil mist is accumulated in the path 5a connecting the vacuum pump 6 and the gabox 5 every time the operation and stop are repeated, Since the rotor chamber 3 and the gusset 5 are at the same low pressure state by the same vacuum pump 6, there is no pressure difference between the rotor chamber 3 and the gusset 5, and the oil from the gusset 5 is passed through the oil seal to the rotor chamber 3. Mist is mixed in, the oil in the vacuum pump 6 and the gas box 5 flows backward and the oil mist is mixed in the laser gas circulation system K through the connection path 6a, and the total reflection mirror and the output mirror in the system are contaminated. Adhesion of oil mist to 8,8 'caused anxiety about discharge, and eventually caused a reduction in laser output.

OBJECT OF THE INVENTION The object of the present invention is to eliminate the above-mentioned conventional drawbacks.
Prevents oil mist from entering the laser gas circulation system,
It is an object of the present invention to provide a gas laser device capable of preventing a decrease in laser output and surely obtaining a stable output.

Configuration of the Invention A gas laser device of the present invention, a discharge tube, and a roots blower having a box that circulates a laser medium in the discharge tube and oil seals a blower shaft,
A vacuum pump that maintains a constant pressure inside the discharge tube and decompresses the inside of the gap box, and is interposed between the circulation path of the laser medium and the vacuum pump, and connects the gap box and the vacuum pump. And an oil mist separator located closer to the circulation path of the laser medium than the other part. As a result, it is possible to prevent oil mist from being mixed into the rotor chamber through the connection path of the vacuum pump, and also to prevent oil from being mixed into the rotor chamber through the oil seal.

Description of Embodiments One embodiment of the present invention will be described with reference to FIG. That is, 1 to 8, 8 ', E, K are the same components as described above,
The description is omitted. 9 is an oil mist separator,
It is provided on the connection path 6a of the vacuum pump 6.

By interposing the oil mist separator 9 at the position shown in the figure, the oil mist existing in the connection path 5a between the gas box 5 and the vacuum pump 6 and the inflow of the oil mist into the laser gas circulation system K due to the reverse flow from the vacuum pump 6 are introduced. In addition, the pressure in the gusset 5 can be kept lower than the pressure in the laser gas circulation system K by several Torr by the filter of the oil mist separator 9, and the pressure difference between the gusset 5 and the rotor chamber 3 (several Torr). By rotor room 3
It is possible to prevent oil from mixing in.

EFFECTS OF THE INVENTION According to the present invention, it is possible to prevent oil mist from entering the laser gas circulation system, prevent contamination of oil such as the mirror and the discharge electrode, and reliably obtain a stable laser output. be able to. Further, since the oil mist separator can lower the pressure in the gearbox lower than the pressure in the rotor chamber of the roots blower, it is possible to prevent oil mist from mixing into the rotor chamber from the gearbox through the oil seal. There is an effect.

[Brief description of drawings]

FIG. 1 is a schematic diagram including a laser gas circulation system of an embodiment of the present invention, and FIG. 2 is a schematic diagram of a conventional example. 1 ... Discharge tube, 2 ... Roots blower, 5 ... Gabox, 6 ... Vacuum pump, 7 ... Supply section, 9 ... Oil mist separator

Claims (1)

[Claims] 1. A discharge tube, a roots blower having a gap box that circulates a laser medium in the discharge tube and oil seals a blower shaft, and maintains a constant pressure inside the discharge tube and reduces the inside pressure of the gap box. A vacuum pump; and an oil mist separator interposed between the circulation path of the laser medium and the vacuum pump and located closer to the circulation path of the laser medium than the connecting portion between the gap box and the vacuum pump. Gas laser device.