JPH0315273Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field of the Invention The present invention relates to an apparatus for condensing a laser beam to perform predetermined laser processing on a workpiece.

Prior Art A laser beam is generally emitted from a laser oscillator and is irradiated onto the processing surface of a workpiece by a condenser lens. In such an optical path process of a laser beam, since the laser beam itself does not travel straight in a strictly parallel state, scattering and diffusion of the laser beam are unavoidable.

In addition, if there are multiple reflecting mirrors in the path of such a laser beam, these reflecting mirrors cannot be machined into exact flat surfaces and have slightly concave or convex surfaces, so the The laser beam undergoes re-spreading or slight convergence. Therefore, when such a laser beam is focused on the processing surface of the workpiece by a condensing lens, if the condensing lens is moved in the optical axis direction,
The central position of the condenser lens and its focal position change within the optical path of the laser beam. A laser beam in a focused state is influenced by diffusion or convergence phenomena during the optical path, and its focus changes. Such a change in the focal position results in an increase or decrease in the luminous flux density at the focal position,
This will immediately have a negative effect on the accuracy of laser processing.

Purpose of the invention and its solution Therefore, the invention aims to keep the optical path length of the laser beam constant even during processing, thereby avoiding the effects of diffusion and convergence in the middle of the optical path of the laser beam. That's true.

Therefore, in the present invention, the light source of the laser oscillation device and the condensing lens are connected by a bendable beam guide whose optical path length does not change.
In addition, the present invention allows the saddle that supports the condensing lens to be supported while maintaining a constant distance in a plane parallel to the work table that supports the workpiece, and to direct the laser beam to these planes. Therefore, the distance between the condenser lens and the focal point of the laser beam, that is, the processing surface of the workpiece, is always maintained at a constant distance.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of the present invention will be specifically described below based on an embodiment shown in the drawings.

The laser processing device 1 of the present invention has as main parts:
It is equipped with a laser oscillator 2. This laser oscillation device 2 is installed at a fixed position, and the output from its light source 2a, that is, the laser beam 3, passes through a cylindrical beam guide 4 and reaches a head 6 supported by a saddle 5. There is.

This beam guide 4 is constructed by connecting three tubes 7, 8, and 9, for example. These tubes 7, 8, and 9 are connected to each other by rotary joints 10, 11, and 12 so as to be freely rotatable, that is, to be freely bent when viewed in a plane, for example, about three vertical Z axes. The laser beam 3 is
is always guided with a constant optical path length to the condenser lens 14 inside the head 6. The optical axis of this condensing lens 14 is set to be perpendicular to the XY plane.

The saddle 5 is mounted so as to be slidable in the X-axis direction by a guide surface 15a of a horizontal cross beam 15. Note that this cross beam 15 is mounted on a base 17 by a column 16. The base 17 also slidably supports a work table 19 for supporting a work 18 by means of a guide surface 17a on its upper surface. The guide surface 17a is formed in a direction three-dimensionally orthogonal to the cross beam 15, that is, in the Y-axis direction, and the upper surface of the work table 19 is parallel to the cross beam 15.

The beam guide 4 is supported at both ends in a so-called double-supported state, but since it is provided with pair of rotating joints 10, 11, and 12 in the middle, it can be attached to the laser oscillator 2, etc., if necessary. Attached strut 20, rotating sling 22, and strut 2
0 and one end of the tube 8, for example, by a hanging wire 21 or the like. With such support means, the beam guide 4 will not be deformed by its own weight, so the optical path length of the laser beam 3 can be fixed even more accurately.

Function of the invention Next, the function of the laser processing apparatus 1 will be explained.

The work 18 is placed on a predetermined position on the work table 19 and fixed in a positioned state.
In this state, a numerical control device (not shown)
The head 6 is given a motion in the X-axis direction, and the work table 19 is given a motion in the Y-axis direction.
Thereby, the focal position on the optical axis of the condensing lens 14, that is, the processing point 23, can be moved to an arbitrary position with respect to the upper surface of the workpiece 18. During this movement, the plane containing the X-axis and the plane containing the Y-axis are parallel in plane, so the distance between the center point of the condensing lens 14 and the top surface of the workpiece 18 is always kept constant. There is.

On the other hand, the laser beam 3 output from the light source 2a of the laser oscillation device 2 passes through the inside of the beam guide 4, is reflected by the mirror 13 inside, reaches the condensing lens 14, is focused there, and is focused at the focal point, i.e. The laser beam is irradiated to a processing point 23 of the workpiece 18, and the necessary laser processing is performed on the workpiece 18 at the processing point 23.

During such processing, even if the saddle 5 moves in the X-axis direction, the beam guide 4 is bent, so the distance from the light source 2a of the laser oscillator 2 to the processing point 23, that is, the focal position of the condenser lens 14, is
Always constant. Therefore, even if a diffusion phenomenon or a convergence phenomenon occurs in the optical path of the laser beam 3, there is no quantitative change in these phenomena, so that the degree of convergence of the laser beam 3 at the processing point 23 is always constant. As a result, stable machining accuracy can always be ensured.

In addition, in this embodiment, since the saddle 5 is guided separately in the X-axis direction and the work table 19 is guided in the Y-axis direction, the head 6 or the workpiece 18 is guided in the X-axis direction and the Y-axis direction simultaneously. Compared to the conventional type, errors in the guide sliding portion do not accumulate, and the accuracy of positioning control is improved.

Modification of the Idea In the embodiment described above, the three rotary joints 10, 11, 12 of the beam guide 4 are kept to the minimum number, but more can be provided if necessary. Further, the rotational axes of the rotary joints 10, 11, 12 may be in not only the vertical direction but also in other directions. Furthermore, the moving directions of the saddle 5 and the work table 19 only need to be parallel in a plane, and therefore do not necessarily have to be horizontal. Condensing lens 14
The direction of the laser beam 3 projected from the front panel does not necessarily have to be downward.

Note that FIG. 4 shows an example in which the work table 19 is fixed and the column 16 is moved in the Y-axis direction by the guide surface 17a. In this variant, the head 6 moves in the direction of the X-Y axis.

Effect of invention The present invention provides the following unique effects.

First of all, regardless of the amount of movement of the saddle, the light source of the laser oscillator and the focal point of the condensing lens, that is, the processing point of the workpiece, are always constant, and even when the beam guide is bent, the optical path length of the laser beam changes. Therefore, even if a mirror or the like is present in the optical path, it will not be affected by diffusion or convergence on the reflecting surface or aberration, and the degree of convergence of the laser beam at the processing point will always be constant, resulting in high Accurate and stable laser processing can be achieved.

Second, because the plane containing the saddle movement trajectory and the plane containing the work table movement trajectory are parallel in plane, the distance between the optical axis of the condenser lens and the processing point on the plane is always constant. Therefore, stable laser processing can always be performed for the above reasons.

Third, since the saddle and work table are designed to be able to move independently in orthogonal directions, it is possible to drive the saddle in the X-axis and Y-axis directions simultaneously, or to move the work table in the
Compared to a type that is driven simultaneously in the axial and Y-axis directions, errors do not accumulate on the sliding guide surface, and the weight of the moving parts can be reduced, allowing the mechanical guide mechanism to achieve high precision. Can be configured based on

[Brief explanation of the drawing]

Fig. 1 is a front view of the laser processing device of the present invention, Fig. 2 is a plan view of the same device, Fig. 3 is an optical path diagram of the optical system, and Fig. 4 is a part of the laser processing device according to a modification of the present invention. It is a front view. 1... Laser processing device, 2... Laser oscillation device, 2a... Light source, 3... Laser beam, 4...
Beam guide, 5...saddle, 6...head,
7, 8, 9...Tube, 13...Mirror, 14
...Condenser lens, 15...Cross beam, 16...
...Column, 17...Base, 18...Work, 1
9...Work table.

Claims (1)

[Claims for Utility Model Registration] (1) A laser oscillation device installed in a fixed position and a unidirectional laser beam emitted from the light source of this laser oscillation device that is freely bent to create a constant optical path length. a beam guide capable of guiding a laser beam to a laser beam, a condensing lens that condenses a laser beam emitted from the beam guide, a saddle that rotatably supports one end of the beam guide and holds the condensing lens, and the saddle. The machine is equipped with a cross beam that can move the workpiece in one direction within a plane, and a work table that positions and fixes the workpiece to be processed at the focal position of the condensing lens, so that the top surface of the workpiece is aligned with the saddle during processing. A laser processing device, which is set parallel to a moving direction, and has no change in optical path length from the laser oscillation device to the focal point of the condenser lens at any position on the saddle. (2) A utility model registration claim characterized in that the beam guide is constituted by a plurality of tubes, three or more rotary joints provided at the tube connection positions, and a plurality of mirrors provided at the rotary joint positions. A laser processing device according to scope 1. (3) Utility model registration claim 1, characterized in that the work table is mounted so as to be movable in a plane parallel to the plane of movement of the saddle in a direction perpendicular to the direction of movement of the saddle. The laser processing device described. (4) Utility model registration claim 1, characterized in that the work table is fixed in a fixed position, and the cross beam is movably mounted by a column in a direction perpendicular to the moving direction of the saddle.
The laser processing device described in Section 1.