JP2000288767A - Laser beam machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve reliability of machining and working efficiency by preventing an optical system in a laser beam machining head from contamination due to a spatter generated in laser beam machining. SOLUTION: Relating to a laser beam machine that an object to be machined is irradiated with a laser beam converged by a converging lens or a converging mirror 3 arranged at a laser beam machining head and laser beam machining is conducted, a nozzle 6 having an injection hole to inject a high speed fluid from the direction roughly orthogonal to an optical axis of the laser beam, is arranged between a machining torch 4 and the converging lens or the converging mirror 3, plural fins 11 arrayed with avoiding a passing part of laser beam is arranged between a machining torch 4 and the converging lens or the converging mirror 3. The spatter intruding into the laser beam machining head is caught by the fins 11, contamination of the optical system is reduced, reliability of machining and working efficiency are improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser processing apparatus for welding a metal material or the like with a laser beam, and more particularly, to a protective structure for an optical system such as a condenser lens or a condenser mirror for condensing the laser beam. The present invention relates to a laser processing apparatus provided with

[0002]

2. Description of the Related Art Generally, in a laser processing apparatus, when performing processing such as welding on a member to be processed by a laser beam, spatters generated during the processing sometimes adhere to a lens or a mirror for condensing the laser beam. . Due to the adhesion of the spatter,
Since the welding performance is reduced, it is necessary to frequently clean the lens and mirror in order to prevent this, and as a result, problems such as a reduction in the operation rate of the laser processing apparatus and a reduction in the life of the lens and mirror are caused. Therefore, between the processing torch that irradiates the workpiece with the laser light and the condensing lens or the condensing mirror, a nozzle in which a high-speed fluid is injected from a direction substantially orthogonal to the optical axis of the laser light is formed. Or place
Measures have been taken such as opening the opposing portion of the nozzle to make it easier for spatter to escape. As a conventional example which proposes means for injecting a high-speed fluid from a direction substantially perpendicular to the optical axis of a laser beam for the purpose of preventing spatter adhesion, JP-A-6-114586, JP-A-6-170
577, JP-A-9-164495 and JP-A-9-220687.

[0003]

However, when welding a hot metal material using a large-capacity laser, the heat input is large and the oxide scale is remarkable, so that large-scale spatters may occur. is there. Therefore, even if a nozzle or the like is provided as described above, it is not necessarily effective for sputtering having a large particle diameter and a high scattering speed. further,
Due to equipment space restrictions, it is sometimes difficult to arrange multi-stage nozzles, or it is not possible to secure a sufficient space in the nozzle opposing portion.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problem, and it is an object of the present invention to effectively prevent spatter from adhering to a converging lens or a converging mirror, thereby improving processing reliability and efficiency. It is an object of the present invention to provide a laser processing device capable of performing laser processing.

[0005]

According to a first aspect of the present invention, there is provided a laser processing apparatus, comprising: a condensing lens or a converging mirror provided on a laser processing head. In a laser processing apparatus that irradiates light to the workpiece from the tip of the processing torch and performs laser processing, the laser torch is arranged between the condensing lens or the condensing mirror of the processing torch, avoiding a portion through which laser light passes. A plurality of fins are provided. Further, the laser processing apparatus according to claim 2 of the present invention irradiates a laser beam focused by a focusing lens or a focusing mirror provided on a laser processing head to a workpiece from the tip of a processing torch to perform laser processing. In the laser processing apparatus for performing the above, between the processing torch and the condensing lens or the condensing mirror, there is provided a nozzle having an ejection port for ejecting a high-speed fluid from a direction substantially orthogonal to the optical axis of the laser light. In addition, a plurality of fins are arranged between the nozzle and the condenser lens or the condenser mirror so as to avoid a portion through which the laser light passes. Further, in claim 1 or 2, the plurality of fins are sequentially attached to the inner surface of a fin outer cylinder disposed in a laser processing head so as to surround a periphery of a laser beam passing portion. Item 3). Claims 1 to
3. The fin according to claim 3, wherein the plurality of fins are made of copper and the surface layer is plated with gold.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In a laser processing apparatus according to the present invention, a sputter generated when processing a workpiece by irradiating the workpiece with laser light is focused through a laser beam irradiation opening of a processing torch. The laser beam enters the direction of the lens or the condensing mirror. First, the traveling direction is bent to the opposite side of the nozzle by high-speed fluid such as dry air injected from a direction substantially perpendicular to the optical axis of the laser beam. . The minor spatter is carried out to the open air together with the fluid, but the spatter with a large particle size and high scattering speed is only slightly bent, and the processing torch placed above the nozzle is attached. It scatters on the guide and the frame of the processing head body further above. The spatters that have collided with them are partially adhered at the same time as the collision, but reflect a considerable amount, and eventually adhere to the condenser lens or the condenser mirror or the flat mirror in front of the condenser lens or mirror. Further, some of the high-speed sputters having an extremely large particle diameter are scattered directly to the upper condensing lens or the condensing mirror almost without being affected by the fluid.

However, if there are a plurality of fins arranged so as to avoid the laser beam at the height position of the processing torch mounting guide or the processing head body frame arranged above the nozzle, the processing torch mounting guide or processing is conventionally required. The sputter that has reached and reflected on the head body frame enters the groove between the fins. The spatter that has entered the groove between the fins is captured and cannot reach the upper condenser lens or condenser mirror. As a result, spatter adherence to the condenser lens or the condenser mirror can be greatly reduced.
It should be noted that a corresponding effect can be obtained even with a plurality of fins without providing a high-speed fluid injection nozzle.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a laser processing apparatus according to the present invention will be described below with reference to the accompanying drawings. FIG. 2 is a sectional view showing the vicinity of a processing head of a conventional laser processing apparatus. Here, a description will be given below by taking a high-energy laser beam obtained by condensing a mirror as an example. The processing head is a path of a laser beam emitted from a laser generator (not shown), and the laser light is reflected and transmitted from a flat mirror 2 disposed on a processing head frame 1 to a condensing mirror 3, and finally transmitted. Focused on the workpiece 9,
Used for laser processing such as welding. A processing torch guide 5 is arranged on the processing torch 4, and in the middle of the processing torch 4, a nozzle for supplying dry air from the side, in this example, an air knife 6, and a dry air and a sputter discharge Rectifying plate 7 and a carry-out opening 8.

In this arrangement of the equipment, the sputter that has entered the direction of the condensing mirror 3 through the laser light guide hole 10 of the processing torch 4 firstly has an air knife 6 in a direction substantially perpendicular to the optical axis of the laser light. The traveling direction is bent to the side opposite to the air knife by the dry air jetted by the nozzle. The minor spatter is carried out together with the dry air from the air knife exhaust hole 8 to the open outside air. But,
The spatter having a large particle diameter and a high scattering speed is scattered in the direction of the processing guide guide 5 above the air knife exhaust hole 8 and the processing head main body frame 1 further above by only slightly bending. . Some of the sputters that collide with these collide with the collision, but they reflect a considerable amount and eventually adhere to the condensing mirror 3 and the flat mirror 2 in front of it.

FIG. 1 shows an embodiment of the present invention. These processing torch guides 5 and the processing head body frame 1 further above
If there are a plurality of sputter capture fins 11 arranged at a height of, avoiding the laser beam, the gap (groove) between the fins
Is trapped in the groove portion and does not reach the upper converging mirror 3. In the present embodiment, a lower end portion is sandwiched by the inner diameter portion of the processing torch guide 5, and a fin outer cylinder 12 extending upward into the processing head main body frame 1 is provided, and a concentric ring shape is formed on the inner surface of the fin outer cylinder 12. The present invention was implemented by brazing a plurality of the sputter capturing fins 11. The fin outer cylinder 12 is arranged so as to surround a peripheral portion of the laser beam.

The mounting pitch of the sputter capturing fins 11 is such that the sputter bent by the dry air from the air knife 6 is reflected from the lower portion of the sputter capturing fins 11 and the outer fin outer tube portion 12 from the area where the sputter capturing fins 11 are installed. Are arranged so as to have an angular relationship that does not protrude. Therefore, the pitch is narrow in the portion of the processing torch guide 5 that is close to the air knife 6, that is, where the intrusion angle of the sputter is deep, and is relatively small in the portion of the processing head body frame 1 that is far from the air knife 6, that is, the shallow angle of the sputter. There is a wide array.

Further, the sputter capturing fins 11 of the present invention
The fin outer cylinder 12 is made of copper, and its surface layer is plated with gold to improve the releasability of sputters captured by the sputter capturing fins 11, and that the spatters adhering to the fins and the outer cylinder are used for periodic repair. Improves removability.

Although the above is one embodiment of the present invention, various embodiments which do not depart from the gist of the present invention, for example, a form in which the processing torch guide 5 is provided with a sputter capturing fin as a single product by machining. Of course, there is a possibility.

[0014]

According to the processing apparatus of the present invention described above, the air knife for injecting dry air and the condensing mirror are disposed between
By arranging a plurality of fins arranged so as to avoid the laser beam passage portion, the amount of spatter adhered to the condensing mirror in this embodiment is less than about 1/2 of the conventional product, and the mirror cleaning frequency is also reduced. １ ／ or less. Therefore, the operation rate of the present laser processing apparatus is improved, the frequency of mirror replacement is reduced, and a great effect is exhibited.

[Brief description of the drawings]

FIG. 1 is a sectional view showing the vicinity of a laser processing head according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view near a conventional laser processing head.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Processing head main body frame 2 Flat mirror 3 Condensing mirror 4 Processing torch 5 Processing torch guide 6 Air knife 7 Air knife straightening plate 8 Air knife exhaust hole 9 Workpiece 10 Processing torch laser beam guide hole 11 Sputter capture fin 12 Fin outer cylinder

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hiroyuki Yamamoto 20-1 Shintomi, Futtsu-shi, Chiba F-term in the Technology Development Division of Nippon Steel Corporation (reference) 4E068 CG03 CH02

Claims (4)

[Claims] 1. A laser processing apparatus which performs laser processing by irradiating a workpiece to be processed from a tip of a processing torch with a laser beam focused by a focusing lens or a focusing mirror provided in a laser processing head. A laser processing apparatus comprising a plurality of fins arranged between the condenser lens or the condenser mirror of the torch so as to avoid a portion through which laser light passes. 2. A laser processing apparatus for performing laser processing by irradiating a laser beam focused by a focusing lens or a focusing mirror provided on a laser processing head from the tip of a processing torch to a workpiece. Between the torch and the condenser lens or the condenser mirror, there is provided a nozzle having an ejection port for ejecting a high-speed fluid from a direction substantially orthogonal to the optical axis of the laser beam, and the nozzle and the condenser lens Alternatively, a laser processing apparatus characterized in that a plurality of fins arranged so as to avoid a portion through which laser light passes are provided between condensing mirrors. 3. A plurality of fins are sequentially attached to an inner surface of a fin outer cylinder disposed in a laser processing head so as to surround a periphery of a portion through which a laser beam passes.
Or the laser processing apparatus according to 2. 4. The laser processing apparatus according to claim 1, wherein the plurality of fins are made of copper and have a surface layer plated with gold.