JPH04258394A - Machining head of laser beam machine - Google Patents

Abstract

PURPOSE:To easily maintain by preventing the contaminated substance splashed from the part to be machined from invading the deep inside the machining head. CONSTITUTION:The laser beam 2 esmitting from the laser oscillator 1 is reflecfted with the mirror 3 and 4, and sent to the lens 15. The lens 15 collects the laser beam 2 at the focus 17 once and sends it to the parabolic surface mirror 6. The screening plate 19 having the passing hole 19a is set at the focus 17. The laser beam 2 passes through the passing hole 19a of this shielding plate 19. The parabolic surface mirror 6 reflects the laser beam 2, collects and irradiates on the part to be machined. On the other hand, the assistant gas 10 for laser beam machining is jetted from the gsa jetting part 20, jetted to the material 7 side to be machined through the passing hole 19a. The contaminated substance 13 splashed from the material 7 to be machined is blown out with this assistant gas 10. So, the contaminated substance 13 does not contaminate the machining head 5. If the contaminated substance 13 invades, it is shielded with the shielding plate 19, and prevented from invading to the light introducing path 12 side.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a processing head of a laser processing machine that processes a workpiece by condensing a laser beam emitted from a laser oscillator, and particularly relates to a processing head of a laser processing machine that processes a workpiece by focusing a laser beam emitted from a laser oscillator. It relates to a processing head of a processing machine.

0002

2. Description of the Related Art In recent years, metal processing techniques using laser processing machines have increased dramatically. FIG. 3 is a schematic diagram of a laser processing machine that has been widely used in the past. In this laser processing machine, a laser beam 2 emitted from a laser oscillator 1 is reflected by mirrors 3 and 4 in a light guide path 12 and advances into a processing head 5 . The light is then focused by a parabolic mirror 6 and irradiated onto the surface of the workpiece 7, which is the focal point. On the other hand, auxiliary gas 10 is guided from a gas cylinder (not shown) to a gas supply section 9 through a gas pipe 8. The auxiliary gas 10 is emitted from the gas supply section 9, is squeezed by a nozzle 11, and is applied to the workpiece 7.
is irradiated. The surface of the workpiece 7 is melted by the interaction between the laser beam 2 and the auxiliary gas 10, thereby achieving laser processing.

0003

However, in the laser processing machine shown in FIG. 3, a large amount of contaminants 13 such as spatter and contaminant gas are scattered from the workpiece 7 and enter the processing head 5. This contaminant 13 contaminates the parabolic mirror 6, and further contaminates the light guide path 12, mirrors 3, 4, etc. Therefore, there is a problem in that these parts must be cleaned frequently, making maintenance difficult. In particular, if the mirror 3 becomes dirty, it becomes difficult to align the optical axis after cleaning.

FIG. 4 is a schematic diagram of a processing head of a laser processing machine designed to prevent such contaminants 13. This laser processing machine uses a parabolic mirror 6 and a nozzle 11.
A window 14 is provided between the two. This window 14 is a transparent material, such as zinc selenide, thereby filtering out contaminants 13.

[0005] However, the window 14 itself is easily contaminated and deteriorated, so it must be replaced frequently. In particular, when spatter or the like adheres to a transparent material, heat accumulates there, making it susceptible to burnout. FIG. 5 is a schematic configuration diagram of a processing head in which the position of the window 14 is devised. In FIG. 5, a window 14 is provided between the mirror 4 and the parabolic mirror 6. Since the parabolic mirror 6 is resistant to contamination, parts further back than the parabolic mirror 6 are protected. This makes the window 14 less susceptible to contamination than in the case of FIG. Therefore, maintenance becomes easier. but,
When performing three-dimensional processing, since the processing head 5 faces sideways or upwards, the window 14 is also contaminated.

As described above, with the structure of the processing head of a conventional laser processing machine, it is impossible to prevent contaminants from entering the light guide path at all as shown in FIG. required frequent cleaning of optical components. Therefore, there was a problem that maintenance was difficult. Furthermore, for these reasons, laser processing machines for three-dimensional processing have been subject to significant limitations in the application of laser processing.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a processing head for a laser processing machine that can prevent contaminants from penetrating deep into the processing head.

Another object of the present invention is to provide a machining head for a laser beam machine that has expanded applications in three-dimensional machining and the like.

[0009]

[Means for Solving the Problems] In order to solve the above problems, the present invention provides a processing head of a laser processing machine that processes a workpiece by focusing a laser beam emitted from a laser oscillator. a first condensing device that once condenses the light at a predetermined position of the light guide path in the processing head;
a second focusing device that focuses the laser beam that has passed through the predetermined position again and irradiates the workpiece; There is provided a processing head for a laser processing machine, characterized in that the processing head includes a shielding plate that provides shielding and is provided with a passage hole through which the laser beam can pass.

0010

[Operation] The laser beam emitted from the laser oscillator is
The light is once focused at a predetermined position on the light guide path by the first light condensing device, passes through the passage hole of the shielding plate, and is further irradiated onto the workpiece via the second light condensing device. Although contaminants are scattered from the workpiece, the shielding plate prevents the contaminants from entering deep inside the processing head.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram of a laser processing machine that is an embodiment of the present invention. In FIG. 1, the same components as in FIG. 3 are given the same reference numerals. A laser beam 2 emitted from a laser oscillator 1 is reflected by mirrors 3 and 4 and sent to a lens (first condenser) 15. The lens 15 is fixed with an auxiliary member 16. The light guide path 12 and the processing head 5 are hermetically separated by the lens 15 and the auxiliary member 16.

The focal point 17 of the lens 15 is
and the parabolic mirror 6. Therefore, the laser beam 2 that has passed through the lens 15 is once condensed at the focal point 17, spread out again, and is reflected by the parabolic mirror 6 (second condenser). The parabolic mirror 6 is formed so that the reflected laser beam 2 focuses 18 on the surface of the workpiece 7. More specifically, the surface of the parabolic mirror 6 is
It is formed to be part of an ellipse with focal points 17 and 18 as the focal point.

A shielding plate 19 is provided in the processing head 5 at a position where the focal point 17 is located. The shielding plate 19 has a passage hole 19a through which only the laser beam 2 focused at the focal point 17 can pass. Further, the shielding plate 19 is provided with an adjustment screw 19b, so that fine adjustment can be made so that the position of the passage hole 19a matches the focal point 17.

A gas injection section 20 is provided between the lens 15 and the shielding plate 19. This gas injection part 20 is
It is connected to a gas cylinder (not shown) via a gas pipe 8. The gas injection unit 20 injects the lens 1 from the hole 20a.
Auxiliary gas 10 for laser processing is injected into the space between 5 and shielding plate 19.

With such a configuration, in the laser processing machine of this embodiment, the auxiliary gas 10 is supplied to the hole 20a of the gas injection section 20.
When the liquid is ejected, it fills the space between the lens 15 and the shielding plate 19. However, since the lens 15 side is made airtight by the auxiliary member 16, the auxiliary gas 10 is
It is blown out from the passage hole 19a toward the workpiece 7 side. Then, while cooling the inside of the parabolic mirror 6 and the processing head 5, it is blown out from the nozzle 11, and the workpiece 7 is irradiated with the laser beam 2. While passing from the passage hole 19a to the nozzle 11, the auxiliary gas 10 blows away contaminants 13 scattered from the workpiece 7 toward the workpiece 7. Therefore, the contaminant 13 does not contaminate the inside of the processing head 5. Even if contaminants 13 should enter the processing head 5, they will be shielded by the shielding plate 19 and prevented from entering the light guide path 12 side.

Therefore, mirrors 3, 4 and lens 1
5 etc. are not contaminated, there is no need to frequently clean them, making maintenance easier. Further, even when this laser processing machine is used for three-dimensional processing, the number of applications increases because the intrusion of contaminants 13 can be prevented.

Next, another embodiment of the present invention will be described. Figure 2
FIG. 2 is a schematic configuration diagram of a laser processing machine that is another embodiment of the present invention. In this laser processing machine, a parabolic mirror 21 is used as a first condenser instead of the mirror 4 in FIG. 1. The laser beam 2 emitted from the laser oscillator 1 is
The light is reflected by the parabolic mirror 21, condensed at the focal point 17, spread out again, reflected by the parabolic mirror 6, and irradiated onto the workpiece 7.

The processing head 5 is provided with gas injection sections 22 and 23 so as to sandwich the shielding plate 19 therebetween. These gas injection parts 22 and 23 are both connected to a gas cylinder (not shown) via a gas pipe 26, and a cleaning gas (for example, purified air) 2 is ejected from holes 22a and 23a, respectively.
Inject 2b and 23b. Laser oscillator 1 on shielding plate 19
A guard plate 24 is provided on the side to prevent the gas 22b from flowing into the light guide path 12. Guard plate 24
is formed such that the closer it gets to the focal point 17, the narrower the distance between it and the shielding plate 19 is. As a result, the gas 22b is ejected more strongly toward the workpiece 7, and the contaminants 13 from the workpiece 7 are blown away toward the workpiece 7.

On the other hand, the gas injection section 23 has a nozzle shape and is configured to inject gas 23b toward the outlet 25. Thereby, the gas 23b discharges the contaminants 13 from the blow-off port 25 to the outside of the processing head 5. In this way, in this embodiment, the gas injection section 22
, 23 can prevent contaminants 13 from entering the laser oscillator 1 side. Note that effects can be expected even if only one of these is used.

[0020]

As explained above, in the present invention, the shielding plate located at the focal point of the first condenser prevents contaminants from entering deep inside the processing head. It is possible to prevent contamination of various parts such as certain mirrors. Furthermore, since the laser beam passes through the passage hole of the shielding plate, there is no problem even if the shielding plate becomes contaminated. This eliminates the need to frequently clean each component, making maintenance easier.

Furthermore, there is no risk of contamination even under adverse conditions such as when the laser beam is applied from below the workpiece.
It can also be used for dimensional processing, increasing the number of applications.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a laser processing machine that is an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a laser processing machine that is another embodiment of the present invention.

FIG. 3 is a schematic configuration diagram of a conventional laser processing machine.

FIG. 4 is a schematic configuration diagram of a conventional laser processing machine.

FIG. 5 is a schematic configuration diagram of a conventional laser processing machine.

[Explanation of symbols]

1 Laser oscillator 2 Laser beam 5 Processing head 6 Parabolic mirror (second condenser) 7 Workpiece 8 Gas piping 10 Auxiliary gas 11 Nozzle 12 Light guide path 13. Contaminants 15 Lens (first condensing device) 17,18 Focus 19 Shielding plate 20, 22, 23 Gas injection part 21 Parabolic mirror (first condenser) 24 Guard plate 25 Air outlet

Claims (8)

[Claims] 1. In a processing head of a laser processing machine that processes a workpiece by condensing a laser beam emitted from a laser oscillator, a first condenser that once converges the laser beam at a predetermined position within the processing head; a second focusing device that focuses the laser beam that has passed through the predetermined position again and irradiates the workpiece; 1. A processing head for a laser processing machine, comprising: a shielding plate that shields a workpiece and has a passage hole through which the laser beam can pass. 2. The laser processing machine according to claim 1, further comprising a gas injection unit provided near the shielding plate to inject gas toward the workpiece from the vicinity of the shielding plate. processing head. 3. The gas injection section is provided closer to the laser oscillator than the shielding plate, and injects the gas toward the workpiece through the passage hole. Processing head of the laser processing machine described. 4. The processing head of a laser processing machine according to claim 2, wherein the gas injection section is provided closer to the workpiece than the shielding plate. 5. The processing head of a laser processing machine according to claim 1, wherein the first condensing device is a lens. 6. The processing head of a laser processing machine according to claim 1, wherein the first condenser is a parabolic mirror. 7. The processing head of a laser processing machine according to claim 1, wherein the gas is an auxiliary gas for laser processing. 8. The processing head of a laser processing machine according to claim 1, wherein the gas is a cleaning gas.