JPS5994594A - Laser light transmitter - Google Patents

Abstract

PURPOSE:To decrease the change in the shape of a laser beam owing to a thermal effect and to perform stable laser working by providing a cooling means and maintaining the inside of a protection cover at a low temp. CONSTITUTION:A cooling pipe 9 is disposed along the surface of the wall in a protective cover 3 provided in an optical path wherein the laser light 2 emitted from a laser oscillator 1 is conducted via a total reflection mirror 4 to a material 8 to be worked. Both ends of the pipe 9 are connected to a cooler 10 provided on the outside of the cover 3. The cooler 10 is connected to a temp. control unit 11 and the unit 11 is connected to a temp. measuring device 12. A temp. sensor 13 is attached through the wall surface of the cover 3, which sensor 13 is connected to the device 12. The cooler 10 is controlled by the sensor 13 and the unit 11 to maintain the inside of the cover 3 at a low temp. in the stage of operation.

Description

[Detailed description of the invention] [Technical field of invention] The present invention relates to an improvement in a radar optical transmission device.

[Technical background of the invention]

In general, the Rade light obtained by a Rade oscillator is a light with good directivity, and by condensing it with a condensing lens, a high output density can be obtained. It is widely used in various processing processes such as cutting and hardening.

That is, the conventional laser beam transmission device is configured as shown in FIG.
The beam is guided to a total reflection mirror 4 for beam bending through a rib-shaped protective cover 3 for protection and safety. The total reflection mirror 4 bends the Radhe light 2 by 90° and guides it to the condenser lens 5. The radar light 2 is condensed by the condenser lens 5, passes through a processing nozzle 6, and is irradiated onto a workpiece 8 placed on a table 7.

[Problems with background technology]

In the conventional radar light transmission device as described above, the beam shape of the radar light 2 changes due to the thermal effect accompanying the absorption of the air within the protective cover 3 during transmission of the radar light. As a result, in the case of cutting, for example, the diameter and position of the focused spot change, making it impossible to perform normal cutting.

[Objective of the invention]

The purpose of this invention is to reduce absorption during laser beam transmission, reduce shape changes in the Radhe beam due to thermal effects,
An object of the present invention is to provide a radar optical transmission device capable of performing stable laser processing.

[Summary of the invention]

The present invention provides a laser beam transmission device in which a protective cover is provided on the optical path of a laser beam emitted from a laser oscillator to a workpiece via a total reflection mirror, and a cooling means is provided to keep the inside of the protective cover at a low temperature. This is a radar optical transmission device.

[Embodiments of the invention]

Generally, the distortion of the beam shape during laser beam transmission is thought to be due to the distribution of gas density caused by the thermal effect accompanying the absorption of the laser beam by a gas such as air. The absorption of laser light that causes this is CO□ laser light (λ = 10.6 μm)
In this case, it seems that H2O in the air is mainly effective.

On the other hand, the density of H20 vapor when saturated in air is about 209/cTL at 300, and when the temperature is lowered to 30, 1
Decrease by orders of magnitude. Therefore, by keeping the air in the transmission line at a low temperature, the amount of H20 vapor can be reduced, absorption can be reduced, and distortion in the shape of the laser beam can be reduced.

Therefore, the laser beam transmission device of the present invention is constructed as shown in FIG. 2, and the same parts as in the conventional example (FIG. 1) are given the same reference numerals.

That is, a cooling pipe 9 is installed along the wall inside a protection cover 3 in the shape of an i9 ink, for example, which is provided on the optical path of the Raded light 2 emitted from the Raded oscillator 1 and reaches the workpiece 8 via the total reflection mirror 4. Both ends of this cooling nozzle 9 are connected to a cooler 10 located outside the protective cover 3. This cooler 10 is connected to a temperature control unit 11, and this temperature control unit 11 is connected to a temperature measuring device 12i1C. Further, a temperature sensor 13 is installed through the wall surface of the protective cover 3, and this temperature sensor 13 is connected to the temperature measuring device 12.
It is connected to the.

During operation, the cooler 10 is controlled by the temperature sensor 13 and the temperature control unit 11 to maintain the inside of the protective cover 3 at a low temperature.

〔Effect of the invention〕

According to the present invention, since the inside of the protective cover 3 is kept at a low temperature by providing a cooling means, absorption of the radar light 2 during transmission is reduced, and changes in the shape of the laser beam due to thermal effects are reduced. As a result, stable radar processing can be performed.

Incidentally, FIG. 3 shows a modification of this invention, and the same effect as the above embodiment can be obtained. That is, a circulation path 14 is formed as a pipe gas in the protective cover 3, a fan 15 is provided in this circulation path 14, and a meandering cooling pipe 16 is provided to direct the air inside the protective cover 3 in the direction indicated by the arrow. The air is circulated through the air, and the fan 15 is used to forcefully cool the air.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing a conventional laser beam transmission device, FIG. 2 is a schematic diagram showing a laser beam transmission device according to an embodiment of the present invention, and FIG. 3 is a schematic diagram showing a modification of this invention. FIG. DESCRIPTION OF SYMBOLS 1... Rade oscillator, 2... Laser light, 3... Protective cover, 4... Total reflection mirror, 5... Condensing lens, 6... Processing nozzle, 7... Table, 8...Workpiece 9...Cooling pipe, 10...Cooler, 11.
...Temperature control unit, 12...Temperature measuring device, 13.
...Temperature sensor, 14...Circulation path, 15...Fan, 16...Cooling 7 mother iso. Applicant's agent Patent attorney Takehiko Suzue Figure 1 Figure 3 Figure 2 Figure 3

Claims (3)

[Claims] (1) In a laser beam transmission device in which a protective cover is provided on the optical path of the laser beam emitted from a Rede oscillator to the workpiece via a total reflection mirror, a cooling means is provided to keep the inside of the protective cover at a low temperature. A radar optical transmission device characterized by: (2) The cooling means has a cooling pipe arranged inside the protective cover and connected to the cooler, and further controls the cooler by a temperature control unit and a temperature sensor installed inside the protective cover. A radar optical transmission device according to claim 1. (3) The cooling means includes a circulation path provided in the protective cover, a fan provided in the circulation path, and a serpentine cooling A'
The radar optical transmission device according to claim 1, further comprising a temperature control unit and a temperature sensor provided within the protective cover, the radar optical transmission device further comprising a temperature control unit and a temperature sensor provided within the protective cover. .