JPH0536157B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a laser processing machine, for example, a laser processing machine that fixes a workpiece and processes it by scanning the workpiece with a laser beam.

[Conventional technology]

FIG. 4 shows an example of a conventional mirror moving type laser processing machine disclosed in, for example, Japanese Patent Laid-Open No. 59-120393.

In the figure, reference numeral 1 is a fixed tube fixed to a laser oscillator (not shown) and attached to the optical path of the laser beam 2, 3 is a bellows that is connected to the fixed tube 1 and can be expanded and contracted in the optical axis direction, and 4 is a fixed tube attached to the optical path of the laser beam 2. An air vent hole opened on the surface of the bellows 3; 5 a mirror box connected to the bellows 3 and movable by a head drive device 6; 7 a mirror for bending the laser beam 2. , 8 is a mirror holder that supports and fixes the mirror 7; 9 is a mirror holder that focuses the bent laser beam 2 with a lens 10;
This is a head portion for guiding the nozzle hole 12 of the nozzle 11.

Next, the operation of the laser processing machine will be explained.

A laser beam 2 emitted from an oscillator (not shown) passes through a fixed tube 1, a bellows 3, and a mirror box 5, is bent by a mirror 7, is guided to a head section 9, is focused by a lens 10, and is focused at a nozzle 1.
1. Through the nozzle hole 12, the workpiece (not shown)
The mirror box 5 is irradiated upward and moved at high speed in the direction of the optical axis to perform processing.

[Problem that the invention seeks to solve]

The conventional laser processing machine is constructed as described above, and therefore, the following problems occur because the mirror box 5 including the mirror 2 is moved at high speed in the air.

As shown by the dotted line in FIG. 4, the mirror box 5 is moved at high speed in the direction of arrow A for laser processing.

Due to this movement, the volume inside the bellows 3 changes rapidly, so the outside air flows from the air hole 4 to the bellows 3.
flow inside. At that time, dirt, dust, oil mist, etc. floating in the air (hereinafter referred to as floating objects) enter the mirror 7 and It adheres to the surface of the lens 10, and further,
If the laser 2 is irradiated from above, it will cause burn-in. The mirror 7 and lens 10 that have been burned in this way have problems such as a decrease in overall reflection or uneven reflectance, resulting in a decrease in laser power on the workpiece and loss of light focusing characteristics. ing.

This invention was made in order to solve the above-mentioned problems, and prevents the adhesion of floating objects to the mirror and lens surfaces, thereby preventing a decrease in the power of the laser beam and a decrease in the focusing characteristics. The purpose of the present invention is to provide a laser processing machine that can perform stable processing.

[Means for solving problems]

The laser processing machine according to the present invention reciprocates the head part along the opening provided in the duct, always closes the opening of the duct with a sheet that can be wound up at both ends, and further uses a wiper provided in the duct. The inside of the duct is sealed by pressing against the sheet, and the sealed duct is filled with gas that does not affect the transmission of laser light.

[Effect]

In the optical transmission section of the laser processing machine according to the present invention, the movable part of the mirror box is surrounded and sealed by the sheet and the duct provided in the opening of the sheet. There was no intrusion;
Furthermore, there is no change in the volume of the optical transmission section due to movement of the head section, and no outside air flows into the duct.

〔Example〕

Hereinafter, the present invention will be described with reference to FIGS.
This will be explained based on FIG.

Note that the fixed tube 1, laser beam 2, head drive device 6, mirror 7, mirror holder 8, head portion 9, lens 10, nozzle 11, and nozzle hole 12 are all equivalent to those in the conventional device. .

In the figure, reference numeral 21 is a duct, a part of which is provided with an opening 22 through which the head portion 9 moves, and a mirror box 23 is installed within this duct 21. Reference numeral 24 is a sheet, for example, a metal sheet, which is attached at both ends to the sheet winding unit 25 and can be freely wound in either direction. A connected motor, 30 a wiper for keeping the duct 21 airtight, 31 a wiper holding plate, 3
2 and 33 are bolts and nuts for fixing the wiper holding plate 31 to the duct 21, respectively.

Next, the operation of the above embodiment will be explained.

In the laser processing machine of the present invention configured as described above, the head portion 9 is configured as the head drive device 6.
When the sheet is driven to the right in FIG. The sheet 24 is wound up.

At the same time, the motor 26 of the sheet winding section 25 on the left end side of the sheet 24 is rotated to the left at a speed that follows the speed of the head drive device 6, and the sheet 24 is sent out from the winding roller 28.

At that time, the sliding surface between the seat 24 and the duct 21 is pressed down by the wiper 30,
Therefore, the inside of the duct 21 is maintained in a sealed state.

Furthermore, since the mirror box 23, mirror 7, and mirror holder 8 connected to the head section 9 are installed inside the duct, the volume inside the duct 21 does not change at all even when the head section 9 moves. Therefore, the duct 2 due to the movement of the head portion 9
1. No airflow occurs between the inside and outside.

In the above embodiment, the sheet 24 is wound by the motor 26, but the sheet 24 may be wound by the tension of a spring. In other words, any means that can follow the speed of the head drive device 6 and move the sheet 24 smoothly without sagging may be used.

Further, in the above embodiment, the explanation has been made regarding the movement of the head section 9, but the same effects as in the above embodiment can be achieved if the portion moves the laser beam.

Furthermore, in order to further clean the inside of the duct 21, a gas that does not affect the transmission of the laser beam, such as nitrogen gas or dry air, may be filled in the duct.

〔Effect of the invention〕

As described above, in the laser processing machine of the present invention, the head portion reciprocates along the opening provided in the duct, and the opening of the duct is always closed by a sheet that can be wound up at both ends. By moving the head part, floating objects in the outside air can be prevented from entering the duct, and this can prevent a decrease in the power of the laser beam and a decrease in the focusing characteristics, allowing stable processing. It has the effect of being able to In addition, the inside of the duct is sealed with a wiper, and the sealed duct is filled with gas that does not affect the transmission of laser light, so the cleanliness inside the duct is more reliably maintained, resulting in even more stable processing. It has the effect of being able to do the following.

[Brief explanation of the drawing]

FIG. 1 is a partial cross-sectional view showing an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along the - line in FIG. 1, FIG. 3 is a cross-sectional view taken along the - line in FIG. 2, and FIG. 4 is a conventional FIG. 2 is a partial cross-sectional view showing a laser beam processing machine. In the figure, 1...fixed tube, 2...laser light,
9...Head portion, 11...Nozzle, 21...Duct, 23...Mirror box, 24...Seat,
25... Sheet winding section. In each figure, the same reference numerals indicate the same or equivalent parts.

Claims (1)

[Scope of Claims] 1. A duct connected to a laser oscillator and having an opening into which laser light is introduced; a base end inserted into the duct through the opening, and a distal end It has a nozzle in the part,
a head part for irradiating the workpiece with the laser beam; a head drive device for reciprocating the head part along the opening; each section is windable, and includes a sheet that always closes the opening, and a wiper that is installed in the duct and presses the edge of the sheet to seal the inside of the duct. A laser processing machine characterized in that a gas that does not affect the transmission of the laser beam is sealed. 2. The laser processing machine according to claim 1, wherein the sheet is made of a metal material. 3. The laser processing machine according to claim 1 or 2, wherein the sheet is wound in the direction of both ends by either a motor or a spring.