JPH04270091A - Laser beam machine - Google Patents

Abstract

PURPOSE:To present the laser beam machine so that the light deflection direction can be set arbitarily with the very simple composition without changing the inner structure of the laser osilating mechanism 1. CONSTITUTION:At least, two pieces of the phase delaying reflection mirrors 3a, 3b and, at least, two pieces of the phase synchronizing mirrors 4a, 4b are provided at the outside of the laser oscilating mechanism 1 to unit the laser light of lineary polarized light, and also the mirror holder 5 to arranged one part or all parts of the above reflecting mirrors 3a, 3b, 4a, 4b so as to mach the optical axis of the incident light and the emitting light is provided, and the driving mechanism 6 to revolves around the above optical axis provided a the above mirror holder 5.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a laser processing device, and more specifically, it is equipped with a function of arbitrarily setting the polarization direction of laser light, and is capable of low distortion welding, high-speed cutting, and the use of absorbents. The present invention relates to a laser processing device used for processing such as hardening.

0002

2. Description of the Related Art Conventional laser processing apparatuses in which the direction of polarization can be arbitrarily set include those shown in FIG.
It is described in Japanese Patent Laid-open No. 7587, and the one shown in FIG. 4 is described in Japanese Patent Application Laid-Open No. 60-61189.

Among these, in the laser processing apparatus shown in FIG. 3, a glow discharge 53 is generated by applying a voltage while flowing a laser medium gas between an anode 51 and a cathode pin 52, and the laser medium gas is The laser beam 54 is generated by pumping. At this time, the laser beam 54 is oscillated through the polarizer 55, so it is linearly polarized.
The direction of polarization is parallel to the plane of incidence on the polarizer 55.

This laser beam 54 is reflected by a reflecting mirror 55 and focused onto the surface of a workpiece 57 by a lens 56 . Next, the X-axis motor 58 and the Y-axis motor 59 move the workpiece 57 in a curved plane together with the moving table 60, so that the focal point of the laser beam 54 moves relatively on the surface of the workpiece 57. The cutting process is then performed.

At this time, the polarizer 5 is moved by the polarization control motor 61 so that the moving direction and the polarization direction are parallel to each other.
5 is rotated, and the direction of polarization is the laser beam 5 to the polarizer 55.
4, it corresponds to the rotation of the polarizer 55. The polarization control motor 61 is an X-axis motor 58,
It is controlled together with the Y-axis motor 59 by an NC device.

Furthermore, as the polarizer 55 rotates, the optical axis of the laser beam 54 moves circularly on the mirror surface of the total reflection mirror 62, but this is due to the refraction of the polarizer 55, which is tilted at a predetermined angle. This is because the optical axis of the laser beam 54 between the total reflection mirror 62 and the polarizer 55 is eccentric to the rotation axis of the polarizer holder 63.

On the other hand, in the laser processing apparatus shown in FIG.
3, the light is repeatedly reflected between the total reflection mirror 74 and the partial reflection mirror 75, and is amplified, and is output from the partial reflection mirror 75. Therefore, the laser beam 72 becomes linearly polarized light due to the presence of the reflecting mirror 73.

The direction of the linearly polarized laser beam 72 can be changed by controlling the rotation of the reflecting mirror 73 within a range of 0 to 180 degrees. That is, when the XY control section 76 drives the XY table 77 in the X direction, a signal is input from the XY control section 76 to the rotation control section 78,
By controlling the rotation angle of the holder 79 using the signal, the polarization direction of the laser beam 72 can be made to be in the X direction, which is the same as the driving direction of the workpiece 80, and the same can be done in the Y direction.

On the other hand, if the holder 79 is rotated at high speed regardless of the driving direction of the workpiece 80, the laser beam 72 linearly polarized by the reflecting mirror 73 can be equivalently converted into circularly polarized light.

That is, according to such a laser processing apparatus, by adding one optically rotatable reflecting mirror 73, the laser beam 72 can be equivalently circularly polarized, and the workpiece 80 can be driven. The direction of linearly polarized light can be controlled to a state corresponding to the direction.

[0011]

However, in such conventional laser processing equipment, (1) a polarizer is placed inside the resonator at the Brewster angle with respect to the optical axis;
Either the polarization direction of the laser beam is controlled by rotating the resonator, or (2) a reflector is attached to one end of the resonator in a holder whose center of rotation is aligned with the optical axis of the laser beam. This required complex modifications to the internal structure of the laser oscillator itself, such as installing a total reflection mirror to receive the reflected laser light and controlling the polarization direction of the laser light by rotating the holder. , it is difficult to stabilize the discharge for a long time,
Another problem is that it is considerably more expensive than the standard model, and solving this problem has been an issue.

0012

[Purpose of the Invention] The present invention has been made in view of such conventional problems, and by combining a plurality of reflecting mirrors outside the laser generating mechanism, it is possible to achieve a laser generating mechanism without changing the internal structure of the laser generating mechanism. It is an object of the present invention to provide a laser processing device that can arbitrarily set the discharge stability of standard specifications and can arbitrarily set the polarization direction of laser light.

[0013]

[Means for Solving the Problems] A laser processing apparatus according to the present invention includes at least two phase-delayed reflection mirrors and at least two phase-synchronized reflection mirrors outside a laser generation mechanism that emits linearly polarized laser light. and a mirror holder for arranging part or all of the reflecting mirror so that the optical axes of the incident light and the emitted light of the laser beam coincide, and the mirror holder is provided with a drive mechanism for rotating it around the optical axis. It is characterized by having a configuration with the following features.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a laser processing apparatus according to the present invention will be described with reference to the drawings.

FIG. 1 is a diagram showing a first embodiment of the present invention.

First, to explain the configuration, 1 is a laser oscillator that is a laser generation mechanism, 2 is a linearly polarized laser beam emitted from the laser oscillator 1, 3a and 3b are phase delay reflection mirrors, and 4a and 4b are A phase synchronized reflective mirror 5 is a reflective mirror consisting of a combination of one phase delay reflective mirror 3b and two phase synchronized reflective mirrors 4a and 4b, and the optical axis of the incident light and the output light of the laser beam 2 are aligned. 6 is a mirror holder drive which is a drive mechanism that rotates the mirror holder 5 around the optical axis, and has a gear 6b that meshes with the gear 6a. 7 is a condensing lens, 8 is a processing nozzle, 9 is a processing table, 10 and 11 are drive mechanisms for moving the processing table 9 together with the workpiece 12, such as an X-axis servo motor and a Y-axis servo. The servo motors 6, 10, and 11 are all connected to a numerical control device 13 for automatic control.

Next, the operation of such a laser processing apparatus will be explained.

Linearly polarized light PL emitted from the laser oscillator 1
The laser beam 2 of -1 is first changed into circularly polarized light PL-2 by the phase-delayed reflection mirror 3a in the front stage, then enters the mirror holder 5, and is again converted into linearly polarized light PL-3 by the phase-delayed reflection mirror 3b in the latter stage. return. After that, change the polarization direction to PL-3,
Two phase synchronized reflection mirrors 4a while maintaining PL-4,
4b, the light is oriented on the same axis as the original optical axis and exits from the mirror holder 5.

The laser beam 2 is focused near the tip of the processing nozzle section 8 and shaped into an appropriate beam shape to process the workpiece 12. At this time, a command is issued from the numerical control device 13 to the mirror holder driving servo motor 6, the X-axis servo motor 10, and the Y-axis servo motor 11 based on the machining data of the workpiece 12 inputted in advance to the numerical control device 13. . In response to this command, the servo motor 6 drives the mirror holder 5 around the optical axis, and performs the desired processing while always keeping the polarization direction PL-6 at a constant angle with respect to the workpiece 12.

FIG. 2 shows another embodiment of the invention.

In this embodiment, one phase-synchronized reflection mirror 4a is provided outside the mirror holder 5, and two phase-delayed reflection mirrors 3a, 3 are provided inside the mirror holder 5.
It has a total of four reflecting mirrors: b and two phase synchronized reflecting mirrors 4b and 4c.

In such a configuration, the laser oscillator 1
The laser beam 2 of the linearly polarized light PL-11 emitted from the
Enter the mirror holder 5 as -12. Then, after being changed into circularly polarized light PL-13 by the phase-delay reflecting mirror 3a in the front stage, it returns to linearly polarized light PL-14 again by the phase-delay reflecting mirror 3b in the latter stage.

After that, the polarization direction is changed to PL-14, PL-1
5, the two phase synchronized reflection mirrors 4b and 4c align the direction on the same axis as the original optical axis, and the light is emitted from the mirror holder 5. The subsequent operation is similar to that of the first embodiment.

According to this embodiment, although the number of reflecting mirrors increases, since the reflection angle can be set to 45 degrees, it is possible to use a reflecting mirror with a smaller diameter than in the first embodiment, which is economical. be. Furthermore, it is easy to combine with existing laser processing equipment.

[0025]

As described above, according to the present invention, at least two phase-delayed reflection mirrors and at least two phase-locked reflection mirrors are provided outside a laser generation mechanism that emits linearly polarized laser light. In addition, a mirror holder is provided in which part or all of the reflecting mirror is arranged so that the optical axes of the incident light and the outgoing light of the laser beam coincide with each other, and the rotation of the mirror holder is controlled. It is possible to arbitrarily set the standard discharge stability without changing the internal structure, and the polarization direction can be arbitrarily set, which is an extremely excellent effect.

Therefore, by using such a laser processing device, it is possible to utilize the effect of polarized light using the high power laser processing device proposed in Japanese Patent Application No. 2-132287 and Japanese Patent Application No. 2-132291. Processing such as low-strain welding, high-speed cutting, and hardening without the use of absorbent can be efficiently realized in three dimensions.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing an embodiment of a laser processing apparatus of the present invention in which the polarization direction can be arbitrarily set.

FIG. 2 is an explanatory diagram showing another embodiment of the laser processing apparatus of the present invention in which the polarization direction can be arbitrarily set.

FIG. 3 is an explanatory diagram showing an example of a conventional laser processing device in which the polarization direction can be arbitrarily set.

FIG. 4 is an explanatory diagram showing another example of a conventional laser processing device in which the polarization direction can be arbitrarily set.

[Explanation of symbols]

1 Laser generation mechanism (laser oscillator) 2 Laser beams 3a, 3b Phase delay reflection mirrors 4a, 4b, 4c Phase synchronization reflection mirror 5 Mirror holder

Claims (1)

[Claims] 1. At least two phase-delayed reflection mirrors and at least two phase-synchronized reflection mirrors are provided outside a laser generation mechanism that emits a linearly polarized laser beam, and part or all of the reflection mirrors are provided with a laser beam. 1. A laser processing device comprising: a mirror holder disposed such that the optical axes of incident light and emitted light coincide with each other, and the mirror holder is equipped with a drive mechanism for rotating the mirror holder around the optical axis.