Laser welding allows faster and more precise work than the traditional spot welding laser systems. In particular, remote laser welding systems have advantages in terms of translation/movement speed and in terms of problems relating to the movement of the head in function of the tooling necessary to block the components. While a traditional laser head has to move and re-locate at every stretch of welding, SmartLaser technology, developed by Optec for COMAU, is able to work far from the object (>750mm) and move the laser spot simply modifying the working angle of the laser beam and its focal distance.

SmartLaser system is the integration of a focusing and re-positioning module with an anthropomorphic robot. The part of the focus has been fully developed, designed, manufactured and assembled by Optec. It is basically composed by two parts, a collimator and a focus system that, working in symbiosis, allow to have a constant spot welding in a working volume of about 350mm x 450mm x 270°.

The movements of the optic take place via linear motors of up to 8g acceleration, while the rotation of the mirrors and laser head is entrusted by rotary engine capable of achieving very high speeds, about 1300°/s. These characteristics allow the system to be able to break down the welding time of about 7 times compared to other systems on the market

In cutting application, the quality of the spot is very important in terms of dimensional and optical aberration, associated to the need of a variation of the spot, for the countless applications, both in terms of size and in terms of location.

The optical head for laser cutting is, in effect, a zoom lens with a magnification factor of 5X: it is able to vary the spot from 80μm to 400μm with optic fiber input of 50μm in diameter, to vary the distance of cutting with a range of ±10mm from the nominal focal plane with a remarkable spot quality.

It's also possible to cut any material with thickness from 0.2 mm up to 20-25mm! All changes are obtained by linear motor system (3 groups in motion) with high-speed performance and maintenance of the position. There are several of such optical layouts: linear, at 90° and in configuration for 3D cutting. It is not necessary to replace any lens, instead as competitors propose, but only by setting a desired value of position and SPOT via computer. High efficiency and quality of the spot make cutting precise and fast, with great productivity benefits. Similarly, heads are available as fixed lenses for easier cutting applications.

In laser applications, a derivation of the cutting head has been the optical head for the "Cladding" or surface treatment of metal surfaces.

The need to perform a surface treatment (surface hardening, nitriding treatments, anti-wear treatment , etc. ..) without having to thermally stress the mechanical piece, but to act only on the treatment area, has led to the development of these laser optical heads for thermally intervene in local mode on the workpiece. The powders are distributed on the workpiece by specific distributed integrally installed with the optical head (these are standard components available on the market) and the laser head is able to vary the shape of the spot and its dimensions for each specific application. Circular, elliptical, rectangular spots can be generated with up to 4kWatts laser power!

The versatility of this technology is dictated by the speed of its execution, by the very small impact on the rest of the mechanical piece, by a reduction of use of deposited powders and, not last, by a reduction of energy consumption for the process (no more thermal ovens, but focused laser source).

Laser welding is becoming more widespread in the industrial world thanks to its high productivity and reached quality. The fiber laser sources are characterized by very high beam quality, a feature that leads to high irradiance (W/mm2) provided on the material.

During welding, defects due to juxtaposition of parts, although limited to a few tenths of a millimeter, can impair the final quality of the welded piece. In order to industrialize the welding process, it is essential a good coupling tolerance; to reduce the costs of preparation of the plates, it is often required that the geometry of the welding section is sufficiently large to permit this.

A solution, that allows to enlarge the size of the joint while keeping the high irradiance, is to put in oscillation high dynamic laser beam: this technique is commonly called wobbling. Optec has developed a welding head able to put in rotation the laser beam, thereby to generate an axisymmetric tool welding. The rotation of the beam does not require the reversal of motion typical of systems in linear oscillation, whose tuning is somewhat complex due to the accelerations to which the optical system is subjected.

The structure of the head is constituted by an optical collimator and focus and by a module interposed between the two parts, entirely produced by Optec.

The module, completely independent and interfaced with any optical system available on the market, allows to transform any welding head in a wobbling welding system.

This system allow to have a spot welding of a few millimeters, while maintaining high radiance that you would have only with a spot of few tens of microns.
Patent Pending - N° WO2013/072817