JPS5933073B2 - Laser removal equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a laser removal device that removes a substance by condensing and heating a laser beam onto the substance.

In the laser removal device, the removal material adheres to the lens,
There are problems such as the occurrence of bulges in the removed portion, which may become a serious hindrance depending on the field of application. 1st
The figure shows an example of a conventional laser processing machine. A laser beam 2 emitted from a laser device 1 is condensed and irradiated onto a processing portion 6 of a workpiece 5 by a condenser lens 3 to perform processing. At this time, melting, scattering, and evaporation occur, and some of the scattered evaporates 4 remain as deposits 7 on the surface of the lens 3. As a result, the laser light transmittance of the lens decreases, which adversely affects subsequent processing. This is especially a big problem when processing in a vacuum because the process is performed in a vacuum. As a conventional technique for solving this problem, a technique shown in FIG. 2 is known. A container window 11 for maintaining a vacuum between the condenser lens 3 and the workpiece 5, a movable transparent plate 9, and a fixed or movable flat plate 10 having one or more plates L are provided. There is. A portion of the scattered evaporated matter 4 adheres to the flat plate 10 as shown at 7, and a portion that passed through the holes adheres to the transparent plate 9 as shown at 8. By moving the transparent plate 9 before it adheres to the extent that it affects processing, work can be carried out continuously. FIG. 3 Moving the flat plate 12 with the I opening,
Laser light is emitted when the aperture matches the laser optical axis.

The laser beam 2 is condensed and irradiated onto the workpiece 5 by a condenser lens 3, and processing is performed.A flat plate 12 is rotated so that the aperture position is synchronized with the laser irradiation, and a An air flow is generated by the fins 13, and the scattered evaporated matter 4 during processing is swept away and does not rise toward the lens. FIG. 4 shows →l when processing is performed using the conventional processing method. The laser beam 2 is directed to the workpiece 6 of the workpiece 5 by the condensing lens 3.
(- Condensed light is irradiated and removal is performed, but the molten material that pops out at this time remains as an undesirable bulge 14 in the peripheral area.
As a countermeasure against this problem, a double lens system shown in FIG. 5 is known. The center part 15 of the laser beam 2 is a lens Al7
The processed portion 6 of the workpiece 5 is irradiated with condensed light by the lens Bl8, and a bulge 14 is generated around it. The peripheral laser beam 16 is focused only by the lens 17, and the focal point 19 of the lens A
In order to condense the light so that it converges, the bulge 14 is irradiated and the bulge 14 is removed. As mentioned above, individual countermeasures have been considered for the occurrence of adhesion and build-up of removed materials, but there is no known solution that can solve both of these problems at the same time, and complex equipment that combines these two problems is not known. It is easy to imagine what will happen.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the drawbacks of the prior art described above, and to provide a laser removal device that does not cause adhesion of scattered evaporated matter and at the same time does not cause undesirable swelling around the processed area. That is, in the present invention, a movable flat plate having one or more apertures and adjacent transparent plates having the same number of necessary thicknesses is placed between the workpiece and the condenser lens, and the apertures and the transparent plate By sequentially bringing the laser into the optical axis during laser irradiation and processing the same part of the processing part in both conditions, when processing through a transparent plate, processing is performed with the focused pit aligned, and the scattering and evaporation that occurs at that time is avoided. The object is blocked by a transparent plate, and when processing through an aperture, the pit is missed due to the absence of the transparent plate.As a result, the processing laser density is low, so there is only a small amount of evaporated matter.
By melting and stabilizing the unfavorable bulges that have already occurred, by moving the flat plate, there is less adhesion of scattered evaporated matter to a single transparent plate, and continuous work can be performed.

In addition, the present invention provides the above-mentioned laser removal device by applying an oily film to the surface of the transparent plate on the workpiece side and installing a wiper to wipe off the scattered particles attached to the surface of the transparent plate, thereby eliminating the need to replace the transparent plate. This is a device that left the rest of the world. Hereinafter, the present invention will be described in the sixth section.
A detailed description will be given based on an embodiment shown in FIGS. In FIG. 6, the laser beam 2 passes through a condensing lens 3, passes through a transparent plate 21 attached to a movable plate 20 of a window 11 of a vacuum container, and focuses on a processed portion 6 of a workpiece 5, thereby performing removal. The scattered evaporated matter 4 generated during removal adheres to the surface of the transparent plate 21. Therefore, the scattered evaporated matter 4 does not adhere to the window 11. During this machining, the bulge 1 of the machined part as shown in Figure 7a
4 occurs. After this removal process is completed, the movable flat plate 20
to align the thin transparent plate 22 with the laser optical axis.
By doing this, the laser beam 1 focuses 23 in front of the workpiece 5, and the bulge 14 of the workpiece 5 (FIG. 7a)
Since the laser beam is irradiated with focused light at a low power density, almost no processing is performed, and the bulge 14 is melted and stably welded to the base material (FIG. 7 B14). A small amount of scattered evaporation material generated at this time adheres to the thin transparent plate 23. In either case, it is extremely effective to place a cutting board 24 to prevent the film from adhering to transparent plates other than those in the optical path. By doing the above, the flat plate 20 is made into a disk (Fig. 8) and rotated so that the transparent plates 21 and thin transparent plates 22 attached alternately to the flat plate 20f1C are aligned with the optical axis one after another. Therefore, the removal and addition can be carried out continuously in a vacuum without causing the scattered evaporated matter to rapidly reduce the light transmittance.

If the amount attached to the thin transparent plate is sufficiently small, only the opening may be used instead of the thin transparent plate 22. It is well known that vacuum deposition does not adhere well unless the surface to which it is applied is clean. By using this in reverse, if the vacuum side of the window material is intentionally dirty, the scattered evaporated matter that has adhered to the window can be easily removed. FIG. 9 shows one of the other embodiments of the present invention.

The laser beam 2 passes through the condenser lens 3 and enters the window 1 of the vacuum container 25.
1, the processed portion 6 of the workpiece 5 is irradiated with focused light and removed. Then, the scattered evaporated matter adheres to the window 11. window 11
A wiper 26 installed near the window 11 is moistened with low-evaporation oil such as vacuum oil, and the window 11 is wiped with this wiper 26 before processing. However, 27 indicates the wiper movement [TJ. Therefore, the scattered evaporated matter will adhere to the window surface via the oil film. By wiping the window 11 with the wiper 26 before the deposit becomes thick enough to affect processing, the deposit can be easily removed. Figure 10 (
This is an example in which the embodiment shown in Fig. 9 is applied to the embodiment shown in Fig. 6. An oil application wiper 26a is used to stain the surfaces of the transparent plate 21 attached to the flat plate 20 and the thin transparent plate 21 with oil etc. in advance, and a wiping wiper 26b is used to wipe off the adhered surfaces after processing. I'll prepare it for you.
By providing this, deposits on the transparent plates 21 and 22 are removed by a wiper every time, so there is no need to replace them, and work efficiency is significantly improved. In practice, the wiper 26a
, 26b may be used to apply oil or the like and remove deposits at the same time without any problem. Figure 11 is the 10th
The illustrated embodiment is another embodiment in which the rotation of the flat plate 20 is also used for wiping with a wiper.

The laser beam 2 passes through the condensing lens 3 and the window 11 of the vacuum container 25, passes through one of the one or more transparent plates 21 attached to the rotary plate 20, and is condensed and irradiated onto the workpiece 5. Removal processing is performed. Next, the rotating plate 28 is rotated by the rotational force from the drive section. Then, when the thin transparent plate 22 coincides with the laser optical axis, the rotation is stopped, and the laser beam is irradiated in an out-of-focus state, thereby melting and stabilizing the bulge. The above steps are repeated one after another to rotate the rotary plate 20, but a wiper 26c is provided at a certain point in one rotation, and all the transparent plates are always wiped by this wiper 26c once in one rotation. When the disc 20 rotates, the rotational torque is generated by the bevel gears 29, 30.
is transmitted to the shaft 31 via the rotary wiper 26c, thereby rotating the rotary wiper 26c. The wiper 26c is impregnated with oil with low evaporability, and when wiping the wiper 26c, it removes deposits and at the same time coats the transparent plate with an oil film. The circumferential speed of the disk 20 on the wiping surface and the circumferential speed of the wiper 26c are set to be different, and the wiping effect is maintained by causing sliding by the difference in circumferential speed rather than rolling relative to each other. Further, in order to keep the pressure at the optimum level during wiping, a spring 32 that adjusts the pressure to a constant level and a pressure adjustment screw 33 are used to hold down the bearing at the end of the shaft of the wiper 26c. By repeating removal and wiping in this way, work can be continued without having to replace many parts. The phases of the transparent plates 21 and 22 are detected by a drive unit 28 and sent to a laser control unit, and the laser is emitted after confirming that the transparent plates are placed on the optical axis. When the workpiece 5 is rotating, a workpiece rotation phase signal is input to the rotary plate control unit 34, which drives the object and the transparent plate so that they coincide with the laser optical axis at the same time. By sending a phase signal to one drive unit, it is possible to continuously and automatically perform processing in synchronization with the rotation of the workpiece.

As explained above, according to the present invention, it is possible to prevent scattered evaporated matter from adhering to the window in a vacuum, and to perform continuous removal processing while stabilizing the processing buildup. Workability is improved to a large degree, and there is no need to spend time wiping off deposits on the window by breaking the vacuum or replacing the window, which has the effect of significantly improving workability.

[Brief explanation of the drawing]

Figure 1 shows a conventional general laser processing machine, Figure 2 &. Figure 3 shows a conventional laser processing machine that performs laser processing on a workpiece in a vacuum. Figure 3 shows a conventional laser processing machine that performs laser processing on a workpiece by rotating a flat plate with an opening. Figure 4 shows how a workpiece is processed using the conventional laser processing method, and Figure 5 shows how the surrounding bulges are also removed and stabilized using the conventional double lens method. , FIG. 6 is a diagram showing an embodiment of the laser removal device according to the present invention, FIG. 7 a is a diagram showing a state in which the transparent plate shown in FIG. 6 is removed, and FIG. FIG. 8a is a diagram showing a state in which the raised portion is removed and stabilized using a thin transparent plate, FIG. 8a is a diagram showing a state in which the movable flat plate shown in FIG. FIG. 8A is a sectional view taken along the line A-A in FIG. 8, FIG.
The plan view of Figure a, and Figure 10 show the wiper shown in Figure 9.
Figures 11A and 11b show the apparatus when the laser removal apparatus shown in Figure 10 is applied to a workpiece formed of a rotating body. This is a diagram. Explanation of symbols 2... Laser light, 3... Condenser lens,
5... Workpiece, 6... Processing part, 14... Embossed part, 20... Movable flat plate, 21... Transparent plate, 22...
・Thin transparent plate, 24... Control board, 25... Vacuum container, 26... Wiper, 28... Drive unit, 34...
・Rotary plate control section.

Claims (1)

[Claims] 1. In an apparatus that performs removal processing by focusing a laser beam onto a workpiece, a movable member that moves in a direction perpendicular to the laser optical axis is provided between the condenser lens and the workpiece. 1. A laser removal device characterized in that a movable body is provided with a transparent plate and an opening, or two types of transparent plates having different thicknesses are alternately disposed on the movable body. 2. In an apparatus that performs removal processing by focusing a laser beam onto a workpiece, a movable body that is movable in a direction perpendicular to the optical axis is provided between the condenser lens and the workpiece, and the movable body A laser removal method characterized in that two types of transparent plates with different openings or thicknesses are arranged alternately, and a wiper is installed to wipe away scattered objects attached to the surface of the transparent plate on the workpiece side. Device. 3. In an apparatus that performs removal processing by concentrating a laser beam onto a workpiece, a rotary movable body that is rotatable in a direction perpendicular to the optical axis is provided between the condenser lens and the workpiece, and the rotatable movable body is provided between the condenser lens and the workpiece. A transparent plate and two types of transparent plates with different openings or thicknesses are arranged alternately on the body, and a wiper is installed to wipe off the flying debris attached to the surface of the transparent plate on the workpiece side. A laser removal device comprising a drive system that moves at least one of the rotary movable body or the workpiece so that the plate coincides with the laser optical axis and outputs a trigger signal to a laser control unit. .