JPS5814589A - Blower for laser light generating device - Google Patents

Abstract

PURPOSE:To shut out the lubricating oil which will be mixed in the main body of the titled device by a method wherein the vacant space located in the vicinity of the outer circumference of a driving motor and the part adjoining to the inlet port of a blower are coupled using piping, the vacant space and the inner part of the main body of the laser light generating device are interconnected making a detour passing through a labyrinth part, and the difference of pressure applied from the vacant space to the inner part of the main body of the laser light generating device is removed. CONSTITUTION:A vane wheel 14 is installed at the tip of the output shaft 13 of a driving motor 12 which constitutes the blower 10, and a laser medium is exhausted from the inlet port 15 to an exhaust port 16 by means of the vane wheel. An ordinary structure is formed in this constitution, but a bypass passage consisting of a piping 22, an oil mist trap 23 and a piping 24 is additionally provided, and said bypass passage is interconnected to the vacant space 20 made at the outer circumference of the stator of the motor 12. At this point, the conductance of the piping part which forms the bypass passage is sufficiently made larger than that of the labyrinth 18, and also, coupled with the existence of the oil misttrap 23, the vapor of lubricating oil 21 accumulated at the bottom of the blower can be prevented from flowing into the main body of the device.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a blower for a laser beam generator, and more particularly to a blower having a blower drive motor equipped with a bearing lubricating oil supply device.

FIG. 1 shows an example of a conventional carbon dioxide laser beam generator. Electrodes 2.3 are disposed at both ends of the discharge tube 1, and the inside of the discharge tube 1 is filled with a V-ther medium 4 consisting of a mixed gas of CO2, N, and He. When glow discharge 5 is generated between electrodes 2 and 3, laser light is generated by stimulated emission with CO and gas in an excited state. A chamber having mirrors 6.7 at both ends is connected to both sides of the discharge tube 1.
The V-laser light generated in the discharge tube 1 is reflected back and forth between the two sides, is amplified, and a part of it passes through the tube 6 and is taken out as a laser beam 8 to the outside. The suction side of a blower 10 is connected to the chamber where @7 is provided via a heat exchanger 9,
The exhaust side of this blower 10 is connected by a pipe 11 to the chamber in which the pipe 6 is provided. Heat wave f due to glow discharge
t,;x The laser medium 4 in the discharge tube 1 is cooled by the heat exchanger 9 and then fed into the discharge tube 1 again by the blower 10.

FIG. 2 is a detailed sectional view of the blower 10.

An impeller 14 is attached to the tip of the output shaft 13 of the drive motor 12. A suction port 15 is provided in the casing near the tip of the impeller 14, and an exhaust port 16 is provided in the casing near the outer periphery. The output shaft length 3 is supported by bearings 17a and 17b, and a labyrinth 18 is provided on the outer periphery of the output shaft between the n1 bearing 17a and the impeller 14.

Next, a hole extending in the axial direction is formed inside the power shaft 13, and an oil filler port 19 is provided at the upper part near the bearings 17a and 17b.
a and 19b communicate with the hole.

Further, a space 20 is provided between the outer circumference of the stator of the drive motor and the casing forming the outer shell. Furthermore, the bottom of this casing is lubricated with "!72: Futomi Knee, 1° KIAi. To rotate 7 times, the laser medium 4 enters through the suction port 15, passes through the impeller 14, and is guided to the exhaust port 16. Bikaru.

Lubricating oil 21 sucked up through the hole inside the output shaft 13 by centrifugal force is supplied to the bearings 17a and 17b through the oil supply port 19a.
, 1.9b. At this time, the labyrinth 18 prevents the vapor of the lubricating oil 21 from flowing out toward the impeller '14.

By the way, it has been found that the blower 10 having the conventional structure described above has the following problems.

That is, when replacing the laser medium 2 by evacuating the inside of the V-laser light generator with a vacuum pump (not shown) in a housing of about IQ''l'orr, the blower 10, suction port 15, and exhaust port 16 The space 20 between the connected laser beam generator main body and the motor 12 is a labyrinth 1 with small conductance.
It becomes connected through 8. Therefore, the pressure drop in the space 20 is extremely slow compared to the pressure drop speed inside the laser device main body. Therefore, from the space 20,
1. Lubricating oil 2.
1 flows out toward the impeller 14. Therefore, when the laser medium 4 is again filled into the laser device main body, the lubricating oil 21 is mixed into the laser medium 4, resulting in a drawback that the laser oscillation characteristics are significantly impaired.

SUMMARY OF THE INVENTION In view of the above drawbacks, an object of the present invention is to provide a blower for a laser light generating device that prevents lubricating oil from entering the laser device main body through the labyrinth portion.

The present invention provides a space portion near the outer periphery of the drive motor;
The vicinity of the suction port of the blower is connected through piping, and the space and the inside of the laser beam generator main body are communicated by bypassing the labyrinth part, thereby creating a pressure difference from the space of the drive motor toward the inside of the laser device main body. This prevents this from occurring.

An embodiment of the blower for a laser beam generator according to the present invention will be described below with reference to FIG. 3, in which the same parts as those of the conventional blower are denoted by the same reference numerals.

An impeller 14 is attached to the tip of the output shaft 13 of the drive motor 12. This impeller 14 has a structure substantially similar to the conventional example in which the impeller 14 takes in the laser medium from the suction port 15 and discharges it to the exhaust port 16. The difference from the conventional example is that the space 20 provided on the outer periphery of the stator of the drive motor 12 and the suction port 15 are connected through a pipe 22, an oil mist trap 23, and a pipe 24, and there is a bypass passage. It is located where it is set up. The conductance of the piping section forming this pie-pass passage is set to be sufficiently larger than the conductance in the labyrinth 18, and since the oil-missing wrap 23 is inserted in the bypass passage, this This prevents the vapor of the lubricating oil 21 from flowing into the main body of the V-za optical device through the bypass passage.

According to this embodiment, the space 20 of the drive motor 12 and the suction port 15 are communicated with each other through a bypass passage with a large conductance consisting of a pipe 22, an oil mist trap 23, and a pipe 24. This has the effect of eliminating the pressure difference that occurs between the two ends of 18. Therefore, the lubricating oil 21 is prevented from flowing into the main body of the V-laser light generator due to the pressure difference, and the laser light generator can maintain stable laser oscillation characteristics.

In this embodiment, when the blower 10 is in operation, the pressure in the exhaust port 16 is higher than that in the suction port 15 by the pressure head of the blower. Therefore, the space 25 on the back side of the impeller 14 (the pressure in this part is equal to the pressure at the exhaust port 16) is the space 20 of the driving motor 12 (the pressure in this part is equal to the pressure in the suction port 15 due to the bypass passage).
Due to the higher pressure, the laser medium flows into the space 20 through the bilinse 18 only slightly. Therefore, on the contrary, the vapor of the lubricating oil 21 is completely prevented from flowing into the space 25, and the vapor of the lubricating oil 21 is completely prevented from flowing into the main body of the laser beam generator.

As described above, the blower for a laser beam generating device of the present invention has the effect of preventing lubricating oil from entering the laser device main body through the labyrinth portion.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram showing an example of a conventional carbon dioxide laser beam generator, FIG. 2 is a sectional view showing details of the blower in FIG. 1, and FIG. 3 is a laser beam generator according to the present invention. FIG. 2 is a vertical cross-sectional view showing an embodiment of a commercial blower. DESCRIPTION OF SYMBOLS 1...Discharge tube, 2.3...Electrode, 4...Laser medium, 6°7...Bell, 9...Heat exchanger, 10...Blower, 12...For driving Motor, 13!・Output shaft, 1
4... Impeller, 15... Suction port, 16... Exhaust port, 17a, 17b... Bearing, 18... Labyrinth,
19a, 19b... Fuel filler port, 20.25... Space,
21...Lubricating oil, 22.24...Fig. 1 ■ Fig. 2 Diagram 3

Claims (1)

[Scope of Claims] 1. A driving motor that rotates an impeller that circulates a laser medium of an L/- laser beam generator is provided, and a bearing of the motor is constantly supplied with lubricating oil by a lubricating oil supply device. In the blower for a laser beam generator, an internal space of the motor, which communicates with the laser medium suction port via a rotary shaft seal portion of the motor, and a vicinity of the suction port are communicated by a bypass passage made of piping. A proa for a laser beam generator characterized by: 2. The prower for a laser beam generator according to claim 1, characterized in that an oil vapor condensing device is inserted into the bypass passage.