JPS5933075B2 - Laser processing method and device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a laser processing method and apparatus suitable for deburring a workpiece.

In general, machined workpieces have burrs attached to the machined portion, and after machining, it is necessary to perform reprocessing to remove the burrs, a so-called deburring operation.

This can be done manually using a file, or mechanically using a drill or file. However, although the mechanical method is highly efficient, secondary burrs are generated by this operation after deburring, and further work is required to remove them. Furthermore, if the area to be deburred is the opening periphery of a through-hole, it is necessary to deburr both the front and back sides, so the labor required for deburring is large in mass production, creating a major bottleneck in streamlining production. It is becoming. The same applies not only to deburring but also to chamfering and other processing on both the front and back surfaces. The present invention was made in order to eliminate the above-mentioned disadvantages, and the focus of the laser beam is placed inside the through hole to be reworked, and the peripheral edges of the openings at both ends of the through hole are simultaneously reworked before and after the focus. The present invention provides a laser processing method for reprocessing the opening peripheral portion of a through hole with high efficiency and without generating secondary burrs, and an apparatus for implementing this method.

Hereinafter, details of the present invention will be explained with reference to an illustrated embodiment. In FIGS. 1 and 2, a workpiece 1 has a rectangular plate shape, and a through hole 2 is drilled approximately in the center thereof, and burrs 5 are formed on the peripheral edges 3 and 4 of openings at both ends of the front and back sides of the workpiece 1.
, 6 have occurred. In this embodiment, the present invention is applied to reprocessing to remove these burrs 5 and 6. First, the apparatus of the present invention will be explained.

A processing table 12 is mounted on the base 11, and the workpiece 1 is placed on it. Although the processing table 12 is schematically shown, it is a so-called XY table that can move and position the workpiece 1 two-dimensionally. A laser oscillation device 13 is provided above the base 11, and is fixed by a support 14 fixed on the base 11 so that its position can be adjusted in the vertical direction (in this figure). Base 1
1, there are further supports 15 and 16 on both sides of the processing table 12.
has been planted. An annular beam mechanism 19 that converts the laser beam IT from the laser oscillation device 13 into an annular beam 18 is supported and fixed at the top of these pillars 15 and 16, and a converging lens 2 that converges the annular beam 18 is below the annular beam mechanism 19.
0 and the converging lens 2 to the workpiece 1.
A focal position adjustment mechanism 21 for moving the lens 0 forward and backward is fixed so as to be adjustable in position. The above-mentioned annular light flux mechanism 19 has both pillars 1
5 and 16 and to which each part of the annular beam mechanism 19 is attached; and an adjustment body 25 which is made of an annular plate and has a beam diameter adjusting screw 24 on its inner side and is fixed to the frame 23. , which has a conical reflecting surface 26 and is made up of a conical mirror body 28 provided at the center of the frame 23, and an annular plate body, and has a screw 29 fitted to the beam diameter adjustment screw 24 on the outside, and a screw 29 on the inside that fits into the beam diameter adjustment screw 24. It is comprised of a conical inner surface mirror body 31 having a conical reflective inner surface 30 corresponding to the conical reflective surface 26 . The conical mirror body 28 and the conical inner mirror body 31 are coaxially provided, and by rotating the conical inner mirror body 31, it can be moved up and down with respect to the conical mirror body 28. Further, in order to allow the annular beam 18 to pass through, the mounting portion 32 of the frame 23 is supported by a radial thin connecting body (not shown). The focal position adjustment mechanism 21 consists of an adjustment member 21a formed in a substantially annular plate shape, and a position adjustment screw 3 is provided on the inner surface of the adjustment member 21a.
5 is provided, and the mounting holes 36, 36 allow the support 15
, 16, and is fixed in a desired position with a machine screw.

The converging lens 20 includes a lens body 40 and this lens body 4.
It consists of an annular frame 41 that supports 0. Frame 4
1 holds the lens body 40 by a stepped portion 42 formed on the inner surface and a lid body 43, and a screw 44 provided on the outer surface fits into the position adjustment screw 35, so that the adjustment member 2
It is supported by 1a. Therefore, the movement of the adjustment member 21a allows the focal position 45 of the lens 20 to be largely adjusted relative to the workpiece 1, and the rotation of the frame 41 allows precise movement adjustment. The apparatus of the present invention is constructed as described above, and the operation thereof as well as the method of the present invention will be described.

．． The adjustment is performed by introducing an adjustment laser beam (not shown) similar to the processing laser beam 17, for example, from the side. First, the focal point 45 is located at the center of the depth of the hole 2 of the workpiece 1 and on the axis of the hole 2.
/
- (T,=-t) by moving the lens 20 from the focus adjustment mechanism 21VC. Next, the conical inner mirror body 31
is rotated to adjust the outer diameter D of the annular beam 18 so that the laser beam 46 comes into contact with the peripheral edges 3 and 4 of the opening of the workpiece 1. With the above adjustment completed, the processing laser beam 17
, the laser beam 17 is bent at right angles by the conical reflective surface 26 and further bent at right angles by the conical reflective inner surface 30 to become an annular beam 18 and go toward the lens 20, where the annular beam 18 is focused into a laser beam 46 that enters the through hole 2 and is transmitted therethrough.

At this time, the burrs 5 and 6 are immediately vaporized and removed by the laser beam 46. A trigram example Vc. Although an annular beam was obtained by the conical reflecting surfaces 2 and 6 and the conical reflecting inner surface 30, the same effect can be obtained by using two conical prisms 47 and 48 as shown in FIG. .

As detailed above, since the laser processing method of the present invention uses a laser beam, no secondary burrs are generated after processing.

Furthermore, since the focus is placed on the inside of the through hole, both the front and back surfaces can be processed at the same time, resulting in extremely high efficiency and other excellent effects. In addition, the device of the present invention converts the laser beam into an annular beam and then converges it with a converging lens, so the energy density is high both before and after the focal point, making it possible to process the annular beam sufficiently. This provides various excellent effects such as being able to easily adapt to the hole diameter of the workpiece by just adjusting it. Although this embodiment has been described with respect to a straight hole, similar processing can be performed on a tapered hole by adjusting the focal point position.

Further, although the case of deburring has been described, it goes without saying that the present invention may also be applied to chamfering or other processing of the peripheral edge of the opening.

[Brief explanation of drawings]

FIG. 1 is a sectional front view of essential parts of an embodiment of the present invention. FIG. 2 is an enlarged view of the main part of FIG. 1. FIG. 3 is a front view of a main part showing a modification of the main part of the above embodiment. 1...
Workpiece, 2... Through hole, 3, 4... Opening periphery,
12... Processing table, 13... Laser oscillation device, 17.
...Laser beam, 18...Annular beam, 19...
Annular light beam adjustment mechanism, 20... Converging lens, 21... Position adjustment mechanism, 45... Focal point.

Claims (1)

[Scope of Claims] 1. A laser processing method, characterized in that a laser beam is focused within a through hole provided in a workpiece, and peripheral edges of openings at both ends of the through hole are simultaneously processed. 2 a laser oscillation device, an annular beam mechanism that converts the laser beam oscillated from the laser oscillation device into an annular beam and adjusts the diameter of the annular beam, and a device that is provided on the optical path of the annular beam and converges the annular beam. a processing table that supports a workpiece having a through hole through which a laser beam from the convergence lens passes; and a focal position adjustment mechanism that adjusts a distance between the workpiece and the convergence lens. A laser processing device comprising: