Pinpoint laser processing

New technology: Laser cleaning as well as laser pre-treatment and post-treatment of surfaces and for sealing and joining surfaces. There are about 30 applications in automotive engineering alone, especially in electromobility.

Typical applications in the field of electromobility include, for example, the adhesive pretreatment of battery packs, module housings and flanges for battery assembly. Adhesive pretreatment of uncoated battery boxes and components for battery boxes made of aluminum is another significant application. Laser pretreatment eliminates the need for coating as well as the application of an adhesion promoter. Bonding with non-oil-compatible 1K cold-curing PU-based adhesive systems is possible and has already been implemented.

Another field of application for the clean laser is the pretreatment of formed aluminum sheet metal components prior to welding, which is increasingly being used in both classic automotive construction and electromobility. However, precise paint stripping can also be carried out in the area of the sealing zones at the contact point of the battery tray or lid without leaving any residue, thus optimally preparing the sealing areas for an EMC-stable, electrically conductive transition. The battery modules used usually have to be ground-contacted at specific points inside the battery box. This is where the high-precision clean lasers are an advantage, as ground points can be generated in less than a second with process reliability and with an accuracy of a few hundredths of a millimeter. Complex geometries are also possible.

In addition to applications around battery production, there are also applications around the production of fuel cells and the powertrain in the field of electromobility. A special process is used for the partial stripping of enameled copper wire for contacting. In this process, the new special Wireline optics enable all-round processing of wires in throughfeed or static all-round stripping of paint or insulation in the end area. Due to the distribution over four processing surfaces, processing with only one laser system allows cost-effective decoating of hairpins for the production of stators in a cycle of seconds. Not only PA but also PEEK-coated wires can be freed from insulation and optimally welded. In addition, the complete stator is freed from resin residues with Cleanlaser after the impregnation process to enable a precisely fitting and thermally optimally bonded installation in the motor housing.

Precision is of great importance in the laser bonding pretreatment of control units and electronic components as well as in the stripping of paint from the contact surfaces of battery trays. Here, sealing areas are more and more often design-related due to their complex shape and constantly variable width. In order to be able to process these contours with minimal programming effort, Cleanlaser has developed the new Contourscan functionality. This makes it possible to synchronize the movement of the automation technology with the laser beam deflection system in real time.

There are many advantages to the new technology: It is no longer necessary to program the geometry to be processed. The path calculation of the machine is done automatically by importing a suitable dxf contour from the drawing data within a few minutes. Even large components with several square meters of surface can be machined fully automatically. The machine automation and the position of the scanner are synchronized in real time. This means that even circular paths and arcs (such as bolted areas in sealing surfaces) can be processed precisely and without delay. Contour accuracies in the range of a few tenths of a millimeter are possible even for large components. Thanks to the variable and continuous path control as well as the dynamic adjustment of the machine feed depending on the machining width, the sealing and contacting surfaces can usually be machined "in one pass", i.e. without interruption and repositioning. Non-productive times are virtually eliminated and the utilization efficiency of the laser system is optimized. Less laser power and therefore a lower investment and running costs result in better quality and lower cycle time than common path-programmed robot controls.

Cleanlaser offers turnkey automation systems with integrated contourscan technology, which has also found its way into electromobile production. The machines are based on either the modular Cleancell platform or the new Cleangantry, a gantry system technology that features scalable dimensions up to 3 x 6 meters and options such as loading via drawers or rotary indexing tables.

Clean-Lasersysteme GmbH
www.cleanlaser.de