JPH06262382A - Nozzle for laser beam machining - Google Patents

Abstract

PURPOSE:To enable a laser beam machining to a surface to be worked in a narrow space by arranging a total reflection mirror in a housing, making a laser beam from a condenser lens proceed in the right-angled direction, and providing a nozzle tip emitting a laser beam reflected by the reflection mirror, and at the same time, injecting assist gas. CONSTITUTION:In a nozzle for working, it is necessary to protect a 45 deg. total reflection mirror from fused splashes scattering from an object to be worked. A protective glass is arranged between the nozzle tip and the reflection mirror. In addition, this protective glass must be equipped with a hole making assist gas pass through. When the introducing pipe of assist gas projects to the side part of the nozzle for working, since it makes the working space of the nozzle for working narrow by the projection, a gas introducing port to the nozzle for working, is provided on the connecting terminal side of an optical fiber. Therefore, since the laser beam is emitted from the side surface of the nozzle, when there is a space for inserting a nozzle, a laser beam machining is possible.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a laser processing nozzle which enables laser processing in a narrow space.

[0002]

2. Description of the Related Art In a laser processing machine, the output light from a laser oscillator is transmitted by an optical fiber and guided to a processing nozzle,
In general, the gas is emitted from the tip of the nozzle together with the assist gas toward the workpiece. The structure of the laser processing nozzle usually has a connection terminal with an optical fiber at one end of a cylindrical housing, and collimates the laser light emitted from the optical fiber at a constant spread angle into the housing to refract it into parallel light. A lens and a condenser lens that further refracts parallel light from the lens and concentrates it on the front focal point are arranged. At the other end of the case, a condensed laser beam is emitted and the introduced assist gas is injected. It is provided with a nozzle tip having a small hole at the tip for doing so.

[0003]

Such a laser processing nozzle is held by a manipulator of a robot for processing such as welding and cutting. In this type of processing nozzle, the longitudinal axis of the casing is the surface to be processed. However, it has a drawback that it cannot be applied to a work surface in a narrow space where such a posture cannot be taken.

An object of the present invention is to provide a laser processing nozzle capable of performing laser processing even on a surface to be processed in a narrow space.

[0005]

In order to achieve the above object, the laser processing nozzle of the present invention can emit laser light from the side portion of the nozzle housing. That is, a 45 ° total reflection mirror for advancing the laser light from the condenser lens in a right angle direction is arranged in the housing, and the nozzle tip for emitting the laser light reflected by the reflection mirror and ejecting the assist gas is provided on the side surface of the housing. It was set up in.

[0006]

It is needless to say that the position of the 45 ° total reflection mirror must be selected so that it is focused in front of the small hole at the tip of the nozzle tip, and that the mounting angle of this total reflection mirror does not change during use. Need to be installed. This is because a change in the angle of the reflecting mirror causes a change in the focal position of the laser beam, which may damage the tip of the nozzle tip.

Further, in the conventional processing nozzle, a protective glass is provided downstream of the condenser lens in case the molten material scattered from the workpiece jumps through the small hole at the tip of the nozzle tip. In the processing nozzle, it is necessary to protect the 45 ° total reflection mirror from this molten droplet, and it is desirable to dispose a protective glass between the nozzle tip and the reflection mirror. This protective glass must be provided with holes to allow the flow of assist gas, and it is appropriate to provide multiple small holes in the peripheral part that does not interfere with the passage of laser light. It is advisable to arrange two pieces of glass so that they are separated from each other and the small holes do not overlap.

In the conventional processing nozzle, the introduction port for the assist gas is provided between the condenser lens and the nozzle tip.
When this gas introduction pipe extends to the side of the processing nozzle, the working space of the processing nozzle is narrowed by that amount, so the gas introduction port to the processing nozzle is provided on the optical fiber connection terminal side, and one It is advisable to partition the section or to arrange a flat conduit along the side of the housing so that the assist gas is introduced into the 45 ° total reflection mirror installation location.

[0009]

According to the laser processing nozzle of the present invention, the laser beam is emitted from the side surface of the nozzle, so that the laser processing can be performed as long as there is a space for inserting the nozzle. As a result, one of the limitations of laser processing is resolved, and it can be expected to be widely used.

Claims (1)

[Claims] 1. A collimating lens having a connection terminal for connecting to an optical fiber at one end of a cylindrical housing, and refracting laser light emitted from the optical fiber at a constant spread angle into parallel light in the housing. The other end of the housing is provided with a condenser lens that further refracts the parallel light from the lens and concentrates it on the front focal point, and a 45 ° total reflection mirror that advances the laser light from the condenser lens in the right angle direction. A laser processing nozzle comprising a nozzle tip that emits a laser beam reflected by the reflecting mirror and jets an introduced assist gas in the portion.