JPH02165889A - Nozzle of laser beam machine - Google Patents

Abstract

PURPOSE:To prevent the influence by a spatter at the time of working by using a first electrode in which a nozzle is connected to an electromagnetic capacity detector, and a second electrode which is placed in the outside periphery of a first electrode and connected to said electromagnetic capacity detector, and protruding a first electrode from a second electrode. CONSTITUTION:A first electrode 6a protrudes from a second electrode 6c. The protruding part of a first electrode is in a columnar shape in which the tip part is formed like a truncated cone, and in its inside, passages of a laser beam and assist gas are formed. A first electrode and a second electrode are insulated from each other, and as for a material, copper, brass, etc., are desirable. As for a material of an insulating plate 3, an insulating sleeve, and insulators 6b, 6d, ceramic, etc., are desirable. At the time of controlling an interval between the tip of a nozzle 6 and a work 10, a capacitance between both of them is detected by a capacitance detector 9, and an operating signal is sent to a controller so that its value becomes a prescribed value. Since a first electrode protrudes, damage caused by a spatter, etc., is received by only is first electrode, and parts can be replaced easily.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a nozzle for a laser processing machine. More specifically, the present invention relates to a nozzle suitable for processing workpieces having complex shapes.

[Prior art] In order to maintain processing accuracy in a laser processing machine, it is necessary to keep the distance between the nozzle of the laser processing machine and the workpiece (hereinafter referred to as the workpiece) constant so that the workpiece is at the focal point of the laser beam. There is. One method of maintaining a constant distance between the nozzle tip and the workpiece is to use changes in the capacitance between the nozzle tip and the workpiece. FIG. 4 shows a nozzle of such a conventional laser processing machine.

In the figure, (1) is a lens holder that holds a condensing lens ('2J) inside, which is attached to the head body (not shown) of a laser processing machine.The lower end of the lens holder (1) is A nozzle (6) is fixed in an electrically insulated state with a mounting bolt (S) having an insulating sleeve (4) through an insulating plate (3).The nozzle (6) has an inverted hollow truncated conical shape, and its tip An injection port (6f) through which laser light and assist gas pass is formed in the center of the lower end.The nozzle (6) has a first electrode (6a) arranged concentrically from the inside, an insulating 1 (6b) and a second electrode (6C).This insulation 1 (6b) ensures electrical insulation between the first electrode (6a) and the second electrode (6C). 1N pole (6a) is insulated 2 (6b
) is supported by an electrode fixing plate (6e) attached to the second electrode (6C).

(7) is the connection port (6g) provided on the second electrode (6C)
This is a connector that is connected to the A coaxial cable (8) is connected to the end of the connector (7) opposite to the connection port (6g). The first electric wire (8a), which is the core wire of the coaxial cable (8), passes through the inside of the connector (7) and passes through the first electrode (
6a). Further, a second electric wire (8b) outside the first electric wire (8a) is connected to a second electrode (6C) via a connector (7). However, the first electric wire (8a
) and the second electric wire (8b) are connected to an external capacitance detector (9). (g)) is a workpiece to be laser processed.

[Problems to be Solved by the Invention] As explained above, in the nozzle of a conventional laser processing machine, since the second electrode extends to the tip of the first electrode, the tip of the nozzle becomes thick and enters the narrow valley of the three-dimensional workpiece. It was also unsuitable for machining complex three-dimensional shapes such as irregularities on the workpiece surface. In addition, since the end faces of the 1'F4 pole and the second electrode are on the same plane and near the laser emission part, the first and second electrodes may be damaged due to adhesion of spatter during laser processing.
There was also the problem that one pole was easily short-circuited, making it impossible to measure the distance between the nozzle tip and the workpiece.

The present invention has been made in view of the problems of the prior art as described above, and it is an object of the present invention to provide a nozzle for a laser processing machine that can be used for three-dimensional workpieces with complex shapes and is less susceptible to spatter during processing. With the goal.

[Means for Solving the Problems] The nozzle of the laser processing machine of the present invention detects the electromagnetic capacitance between the nozzle tip and the workpiece, and adjusts the movement of the nozzle so as to maintain a constant distance between the two. A nozzle for a laser processing machine according to the present invention, wherein the nozzle is arranged around a first electrode connected to an electromagnetic capacitance detector, and the first electrode is electrically insulated from the first electrode. a second electrode connected to a laser processing machine, the nozzle is installed in a laser processing machine in an electrically insulated state from the workpiece, and
It is characterized in that the tip of the first electrode protrudes from the second electrode.

[Function] In the present invention, since the first electrode is made to protrude from the second electrode, the tip of the nozzle can be made thin, and it is possible to process workpieces with unevenness or narrow parts. Since the end face adjacent to the 1N-pole second electrode and the end face of the second electrode are separated from each other, they are less likely to be affected by sputtering during processing.

[Examples] The present invention will be described below based on Examples, but the present invention is not limited to these Examples.

FIG. 1 is a vertical cross-sectional view of a nozzle of a laser processing machine according to an embodiment of the present invention, and FIG. 2 is a vertical cross-sectional view of a nozzle tip of still another embodiment of the present invention.

In FIGS. 1 to 3, the same or equivalent parts as in FIG. 4 are given the same reference numerals as in FIG. 4, and the explanation thereof will be omitted.

In the embodiment shown in FIG. 1, the first electrode (6a) is more protruding than the second electrode. 11th! The protrusion of the pole (6a) is a cylindrical body with a truncated conical tip, and a passage for the laser beam and assist gas is formed inside.

As the material for the first electrode (6a) and the second electrode (6c), any known electrode material can be used, but it is preferable to use copper, brass, etc. from the viewpoint of electrical conductivity and heat conductivity.

Insulation plate (3), insulation sleeve (4), insulation 1 (6b)
As the material for the insulation 2 (6d), any known insulating material can be used, but from the viewpoint of heat resistance and strength, it is preferable to use ceramic or the like. These insulating materials can be formed, for example, by ceramic spraying. Ceramic spraying allows the insulation to be thinner and the equipment to be more compact.

In this embodiment, the distance between the tip of the nozzle (6) and the workpiece (T) is controlled by measuring the capacitance between them using a capacitance detector ( 9) and sends an operation signal from the capacitance detector (9) to a control device (not shown) of the laser processing machine so that this value becomes a predetermined value.

In this example, ↓, nozzle (6) and workpiece □
Although the distance between the □□ and the □□ was controlled by detecting the capacitance between the two, other electromagnetic methods such as measuring eddy current, magnetic force, etc. may be used.

The embodiment shown in FIG. 2 is different from the embodiment shown in FIG.
Insulation 01) is applied to the base of the protruding portion of the first electrode (6a) to improve short-circuit prevention performance due to sputtering or the like.

The same insulating material as the insulating plate (3) can be used as the material for the insulating OD, and it can be similarly formed by ceramic spraying.

In the embodiment shown in FIG. 2, the insulation 0η is applied to the root of the protrusion of the first electrode (6a), but the insulation 0D may be applied to all the protrusions.

The embodiment shown in FIG. 3 is different from the embodiment shown in FIG.
The electrode (6C) is provided with insulation 01).

In the embodiment shown in FIGS. 2 and 3, the first N pole (
6a) and the second N-pole (6C), so damage caused by sputtering during processing is avoided by reducing the chance of short-circuiting between the first electrode (6a) and the second N-pole (6C).
Since only the first electrode (6a) is affected, parts must be replaced only when the first electrode (6a)
), and maintenance costs are low.

[Effects of the Invention] As explained above, when using the nozzle of the laser processing machine of the present invention, since the first electrode is made to protrude more than the second electrode, it is possible to process workpieces with complex shapes, and it is possible to process workpieces with a complicated shape. Since only the first electrode is damaged by sputtering or the like, parts need to be replaced only for the first electrode, resulting in low maintenance costs.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of one embodiment of the nozzle of the laser processing machine of the present invention, FIG. 2 is a longitudinal cross-sectional view of another embodiment of the nozzle of the laser processing machine of the present invention, and FIG. FIG. 4 is a vertical cross-sectional view of a nozzle tip of still another embodiment of a nozzle for a laser processing machine, and FIG. 4 is a vertical cross-sectional view of a conventional nozzle. (Main symbols in the drawing) (1): Lens holder (6): Nozzle (7): Connector (8) Twin coaxial cable (to): Work Figure 1

Claims (2)

[Claims] (1) A nozzle for a laser processing machine that adjusts the movement of the nozzle by detecting electromagnetic capacitance between the nozzle tip and the workpiece so as to maintain a constant distance between the two, wherein the nozzle is connected to the electromagnetic capacitance detector.
an electrode, and a second electrode disposed on the outer periphery of the first electrode in an electrically insulated state and connected to the electromagnetic capacitance detector, and the nozzle performs laser processing in an electrically insulated state from the workpiece. 1. A nozzle for a laser processing machine, which is attached to a laser processing machine, and wherein a tip of the first electrode protrudes beyond the second electrode. (2) The nozzle for a laser processing machine according to claim 1, wherein a predetermined portion of the protruding portion of the first electrode is coated with an electrically insulating material.