JPH03146290A - Laser welding machine - Google Patents

Abstract

PURPOSE:To exhibit the output of an oscillator to the highest possible extent when the low output is executed by providing plural attachable and detachable laser torches in a high-output laser welding machine and nearly equally distributing the laser outputs to the laser torches. CONSTITUTION:The laser beam 1 released from the CO2 laser oscillator is bisected by a splitting mirror 2 having 45 deg. reflecting surface and is spectrally split in diametrically opposite directions. The spectrally split laser beams 4a, 4b are then respectively deflected toward a moving base 6 by reflecting mirrors 5a, 5b. Condenser lenses 8a, 8a are provided in these polarizing optical paths and the focal positions of the condenser lenses are constituted as laser beam torches. Even the output of the oscillator for which just the low output is needed is, therefore, produced to the max. possible extent and the shortening of the welding time is possible. The splitting mirror 2 is merely necessitated to be removed from the laser optical paths when the laser welding machine is desired to be used at the max. output.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a laser welding machine, and more specifically, to significantly reduce the takt time (welding time) of steel materials with small plate thickness even with a high-output laser welding machine. This is related to a traditional laser welding machine that can do this.

Conventional technology In recent years, laser welding methods have been widely used for welding steel plates. In this laser welding method, Figs.
As shown in the figure, due to the relationship between welding speed, penetration depth, welding speed, laser output, and cross-sectional shape of the welded part, welding with a large plate thickness is performed using a high-power laser, and welding with a small thickness is performed using a high-power laser. Welding is generally performed using a high-power laser. However, in this laser welding, the maximum output of the laser welding machine is determined by the output required to weld steel materials with large plate thickness, so when welding small plate thickness, the specifications of the welding machine tend to be excessive. .

In addition, as described in Japanese Patent Application Laid-open No. 58-65592, one laser beam is divided into two, a metal that absorbs the laser beam is coated with one of the divided laser beams to form a metal covering, and the other is divided into two. There is a method of welding base metals together by laser welding by emitting a metal coating formed by split laser beams.

However, although this method can weld base materials that are difficult to laser weld using two-step welding, it cannot maximize the output of the oscillator when welding small plate thicknesses that require only low output power. There was a problem.

Problems to be Solved by the Invention The purpose of the present invention is to solve the above-mentioned problems. Specifically, the present invention uses a welding machine with the maximum capacity necessary for each type of steel material to be welded, and uses a laser for welding steel materials with small thickness. The purpose of the present invention is to propose a laser welding machine that uses a plurality of torches by spectroscopy and can significantly reduce takt time.

Means for Solving the Problems and Their Effects Namely, the present invention provides a high-power laser welding machine with a plurality of removable laser torches, and is structured so that the laser power distribution to the laser torches is approximately equal. It is characterized by:

Hereinafter, the structure and operation of the means of the present invention will be explained in detail with reference to the drawings.

In addition, FIG. 1 and FIG. 2 are explanatory diagrams each showing an example of an apparatus used when carrying out the present invention, and FIG.
The figure is a graph showing the relationship between welding speed and penetration depth, and FIG. 4 is an explanatory diagram showing the relationship between welding speed, laser output, and welded part cross-sectional shape.

First, as shown in FIG. 1, a laser beam 1 emitted from a C02 laser oscillator (not shown) is divided into two parts v1 by a splitting mirror 2 having a 45 DEG reflective surface, and is split into two parts v1 in opposite directions.

The optical system including this split mirror 2 is capable of reciprocating in a direction perpendicular to the optical axis of the laser beam 1.

Spectral laser beam 4a separated into two directions by split mirror 2,
4b are respectively deflected toward the movable table 6 by reflecting mirrors 5a and 5b, and a condensing lens 8a is provided in their polarized optical path.
, 8a are provided, and the focal position of the condenser lens is configured as a laser beam torch.

With this configuration, laser light is supplied from the plurality of torches with approximately equal output distribution according to the thickness of the thin steel plate, and the welding part can be reliably welded and the maximum output, for example. If the welding time is 1/2 or less, the welding time can be reduced to approximately 172 seconds. In addition, the first
The dashed line in the figure shows the optical path when the split mirror is removed. In another embodiment, as shown in FIG. 2, a triangular prism 9 with a reflectance adjusted to 50% is used in place of the split mirror in FIG. 1, but the effect is the same as in the first embodiment. be.

In Examples 1 and 2, the laser beam is divided into two equal parts. However, the invention is not limited to this, and the laser light may be divided into any number of parts depending on the thickness of the plate.

Note that if you want to use the laser welding machine at maximum output, you can remove the split mirror or triangular prism from the laser beam path.

Example Hot rolled steel plates were welded on a pickling line using a beam welding machine shown in FIG.

In this case, hot rolled steel plates with a thickness of 611 Il were welded with a laser output of 10 KW without using a triangular prism.
During welding, a 2 m thick thin plate was divided into two halves using a triangular prism and welded with W at an output of 5. The welding time for the thin plate was 30 seconds in the conventional method, but it was 15 seconds in the example. Ta.

<Effects of the Invention> As explained in detail above, the present invention provides a high-output laser welding machine with a plurality of detachable laser torches, and is structured so that the laser output distribution to the laser torches is approximately equal. It is characterized by:

According to the present invention, since the laser beam is divided and used, the output of the oscillator side can be maximized even in welding that requires only a low output power, and the welding time can be significantly reduced. .

[Brief explanation of the drawings] Figure 1 and Figure 2 are explanatory diagrams showing an example of [2] used when carrying out the present invention, and Figure 3 shows the relationship between welding speed and penetration depth. The graph shown in FIG. 4 is an explanatory diagram showing the relationship between welding speed, laser output, and welding part surface shape. Code 1...Laser beam 2...Split mirror 4a, 4b...Spectral laser beam 5a, 5b...Reverse! ) 1 Mirror 6...Moving table 1...Workpieces 8a, 8b...Condensing lens 9...Triangular prisms 9a, 9b...・Semi-transparent mirror

Claims (1)

[Claims] 1. A high-output laser welding machine, characterized in that a plurality of detachable laser torches are provided, and the laser output distribution to the laser torches is approximately equal. Laser welding machine. 2) Claim 1, wherein the laser torch is configured with a triangular prism or a split mirror interposed in the laser optical path.
Laser welding machine described.