JPH0647575A - Optical scanning type laser beam machine - Google Patents

Abstract

PURPOSE:To enlarge an allowable stroke and to execute laser beam machining in a wide range in an optical scanning type laser beam machine. CONSTITUTION:A moving condensing system 8 is composed of a beam diameter correcting lens 20, reflecting mirror 5 and condenser lens 6 and their positions are controlled by command from a CNC 100 as represented by arrows 9. The beam diameter correcting lens 20 is provided short of the reflecting mirror 5 and its position is controlled by the command from the CNC 100 as represented by the arrow 21. Thus, even when the moving condensing system 8 is moved and the beam diameter D1 on the condensor lens 6 is changed due to its movement, the beam diameter D1 is held at a fixed value by controlling the position of the beam diameter correcting lens 20. That is, even when the stroke of the moving condensing system 8 is enlarged from the nearest point S3 to the farest point S4, laser beam machining in a wide range is executed while the uniform machining quality is maintained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical scanning type laser processing machine for concentrating and irradiating a laser beam onto a work by using a moving condensing system, and more particularly to a stroke (optical scanning stroke) of the moving condensing system. The present invention relates to an optical scanning type laser processing machine which is expanded.

[0002]

2. Description of the Related Art Laser processing machines are widely used for processing such as cutting and welding. As the laser processing machine, an optical scanning type laser processing machine of a type in which a moving focusing system is moved to perform laser processing is known.

FIG. 2 is a diagram schematically showing a conventional optical scanning laser processing machine. The laser oscillator 1 comprises a total reflection mirror 2 and an output coupling mirror 3, and outputs a laser beam 4. The laser beam 4 expands in diameter due to a diffraction phenomenon when propagating in the free space, and enters the moving light converging system 8. The laser beam 4 that has entered the moving light condensing system 8 is deflected by the reflecting mirror 5 and then condensed by the condensing lens 6 to irradiate the work 7.
The position of the moving light condensing system 8 changes as shown by an arrow 9, and the laser beam 4 scans the work 7 according to the change.

The beam diameter D of the laser beam 4 is D1 on the condenser lens 6. Further, on the work 7, the light is not focused on one point of the focus, but is focused on the spot diameter D2.

[0005]

The above-mentioned conventional optical scanning type laser beam machine has the following drawbacks. The spot diameter D2 is
It depends on the beam diameter D1 on the condenser lens 6. Since the beam diameter D1 changes as a function of the position of the moving light focusing system 8, as a result, the spot diameter D2 also changes as a function of the position of the moving light focusing system 8. This is the calf (cutting groove)
Means that it changes at different positions on the work 7, so that uniform cutting quality cannot be guaranteed.

Further, the spot diameter D2 varies depending on various conditions such as the material of the work 7, the plate thickness, the surface condition, and the required cut surface roughness, and it is difficult to always optimize it. Therefore, the spot diameter D2 and the kerf are held to be optimum only when the beam diameter D1 happens to meet various conditions of the work 7. In that case, the allowable stroke S of the moving light converging system 8 is from the closest point S1 to the farthest point S2 shown in the figure.
However, the range is too small for general use. Thus, in the conventional optical scanning laser processing machine,
The range of laser processing was limited to a narrow range.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an optical scanning type laser processing machine capable of enlarging an allowable stroke and performing laser processing in a wide range.

Another object of the present invention is to provide an optical scanning type laser processing machine capable of performing laser processing with an optimum kerf for each work.

[0009]

According to the present invention, in order to solve the above-mentioned problems, an optical scanning laser for performing processing by converging and irradiating a laser beam output from a laser oscillator onto a work by using a moving condensing system. In a processing machine, light including a condenser lens of the movable condenser system and an optical component provided in the movable condenser system and capable of controlling a mutual distance between the condenser lens. A scanning laser machine is provided.

[0010]

In the moving light condensing system, the condensing lens and the optical component capable of controlling the mutual distance between the condensing lens are provided. Therefore, even if the moving condensing system moves and the beam diameter on the condensing lens changes due to the movement, the beam diameter can be maintained at a constant value by controlling the position of the optical component. Therefore, the allowable stroke of the moving light converging system can be expanded, and laser processing in a wide range becomes possible.

Further, when the optimum beam diameter on the condenser lens is set for various conditions such as the work material, plate thickness, surface condition, required cut surface roughness, etc., the position of the optical component should be controlled. Thus, the beam diameter can be constantly controlled to the optimum beam diameter. Therefore, the spot diameter is always optimally controlled, and it becomes possible to perform laser processing with an optimal kerf for each work.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram schematically showing an optical scanning laser processing machine of the present invention. The optical scanning laser processing machine of the present invention is C
It is composed of an NC 100, a laser oscillator 1 and a moving light condensing system 8.

The laser oscillator 1 comprises a total reflection mirror 2 and an output coupling mirror 3, and outputs a laser beam 4. Moving light collection system 8
Is composed of a beam diameter correction lens 20, a reflecting mirror 5 and a condenser lens 6, and its position is represented by a CNC as shown by an arrow 9.
It is controlled by a command from 100. The beam diameter correction lens 20 is provided in front of the reflecting mirror 5, and its position is controlled by a command from the CNC 100 as indicated by an arrow 21. By controlling the position of the beam diameter correction lens 20, the mutual distance between the condenser lens 6 and the beam diameter correction lens 20 can be controlled. Beam diameter correction lens 20
A long-focus lens or the like is used for this. The moving light condensing system 8
The position control of the beam diameter correction lens 20 is performed via a mechanism of a servo motor and a ball screw (not shown).

The CNC 100 is a processor (not shown).
And controls the entire laser processing machine based on a processing program. That is, a laser output command is output to the laser oscillator 1 and, as described above, a movement command is output to the moving focusing system 8 and the beam diameter correction lens 20, respectively, for control. Furthermore, CNC100
The memory (not shown) constituting the
The optimum beam diameter D10 on the condenser lens 6 is preset for various conditions such as plate thickness, surface condition, required cut surface roughness, and the like. The CNC 100 outputs a position command signal for the beam diameter correction lens 20 based on the optimum beam diameter D10.

The laser beam 4 output from the laser oscillator 1 is incident on the moving light condensing system 8 and is then irradiated on the work 7 via the beam diameter correcting lens 20, the reflecting mirror 5 and the condensing lens 6. . Laser processing is performed by the irradiated laser beam 4.

As described above, in this embodiment, the moving light condensing system 8 is used.
Inside, a condenser lens 6 and a beam diameter correction lens 20 whose mutual distance between the condenser lens 6 can be controlled are provided. Therefore, even if the moving condensing system 8 moves and the beam diameter D1 on the condensing lens 6 changes due to the movement, the position of the beam diameter correcting lens 20 is controlled to keep the beam diameter D1 at a constant value. can do. That is, the stroke of the moving light converging system 8 is set to the closest point S3 as shown in the figure.
From the farthest point S4 to the farthest point S, the beam diameter D1 can be maintained at a constant value, and the movable range of the moving light condensing system 8 is greatly expanded. Therefore, it is possible to perform laser processing over a wide range while maintaining uniform processing quality.

The optimum beam diameter D10 is set in advance for various conditions such as the material of the work 7 and the beam diameter D1 is set.
The position of the beam diameter correction lens 20 is controlled so that the beam diameter is held at the optimum beam diameter D10.

For example, when cutting a thin plate, it is necessary to reduce the kerf to increase the speed and improve the surface accuracy. Therefore, the optimum beam diameter D10 is set so that the kerf can be reduced. Further, when cutting the thick plate, it is necessary to enlarge the kerf and smooth the flow of the auxiliary gas, so the optimum beam diameter D10 is set so that the kerf becomes large. The position of the beam diameter correction lens 20 is controlled according to the optimum beam diameter D10. Therefore, the laser processing can be performed with the optimum spot diameter D2 corresponding to each work 7, and the laser processing can be performed with the optimum kerf. In this way, since the laser processing is performed with the optimum kerf for each work 7, a high degree of intelligence of the laser processing machine can be achieved.

[0019]

As described above, according to the present invention, in the moving light condensing system of the optical scanning laser processing machine, the condensing lens and the optical component in which the mutual distance between the condensing lens can be controlled. And. Therefore, even if the moving condensing system moves and the beam diameter on the condensing lens changes due to the movement, the beam diameter can be maintained at a constant value by controlling the position of the optical component. Therefore, the allowable stroke of the moving light converging system can be expanded, and laser processing can be performed in a wide range while maintaining uniform processing quality.

Further, the beam diameter on the condenser lens can be controlled to an optimum beam diameter set corresponding to each condition of the work. Therefore, the spot diameter is always optimally controlled, and the laser processing with the optimal kerf becomes possible.

[Brief description of drawings]

FIG. 1 is a diagram schematically showing an optical scanning laser processing machine of the present invention.

FIG. 2 is a diagram schematically showing a conventional optical scanning laser processing machine.

[Explanation of symbols]

 1 Laser Oscillator 4 Laser Beam 5 Reflector 6 Condenser Lens 7 Work 8 Moving Condenser System 20 Beam Diameter Correction Lens 100 CNC (Numerical Controller)

Claims (3)

[Claims] 1. An optical scanning laser processing machine for performing processing by concentrating and irradiating a laser beam output from a laser oscillator onto a work by using a moving focusing system, wherein a focusing lens of the moving focusing system, An optical scanning laser processing machine, comprising: an optical component that is provided in the moving light condensing system and is capable of controlling a mutual distance between the movable light condensing system and the condensing lens. 2. The optical scanning laser processing machine according to claim 1, wherein the control of the mutual distance is performed by a CNC. 3. The optical scanning laser beam machine according to claim 1, wherein the control of the mutual distance is performed based on data set in advance so that the workpiece can be optimally processed. .