New multifunctional laser head

Line processing head for laser transmission welding

30 % lower processing costs for polymer bonding

Fiber-reinforced thermoplastics and the use of laser transmission welding are opening up entirely new possibilities of functionalization and design in lightweight automobile construction. The newly developed and highly compact line processing head “LPH-L” from LIMO Lissotschenko Mikrooptik GmbH can reduce processing costs by up to 30 % and enables the processing of parts previously considered too complex.

LIMO’s new laser processing head “LPH-L” offers a unique combination of five features:

  • At only 153 mm x 90 mm, it is up to 50 % more compact than comparable processing heads.
  • Four welding geometries are possible using one and the same multifunctional laser head (welding points, surfaces, contour welding and continuous materials). Thus “LPH-L” offers a wide range of welding options – without scanner technology.
  • Temperature-regulated processing and data logging are already integrated into the laser system.
  • Weighing only 1200 g, the compact and robust head can be deployed on lightweight robot arms.
  • The “LPH-L” is newly designed, less complex and can reduce processing costs in comparison to similar systems by up to 30 %.

Peter Bruns, Director Application and Customer Service at LIMO, summarizes the advantages of the new “LPH-L” as follows: “With LIMO’s new compact line processing head, suppliers of lightweight automobile components can now serve the middle and low-cost market segments as well as the high-end segment.”

The new processing head allows laser welding in four geometries

Together with a fiber-coupled industrial laser system, the compact processing head “LPH-L” can generate a 12 x 2 mm welding line. By rotating the processing head, the welding line can be adjusted to a minimum length of 5 mm. By variable handling of the line processing head (e.g. mounted on a robot arm), it is possible to achieve diverse welding geometries using only one tool. In addition, the processing head is able to compensate for level differences in the component of up to 12 mm.

The “LPH-L” also allows welding spots to be applied in the form of short lines of e.g. 10 mm. These “line-spots” are more strain-resistant than standard spots. The laser head is also able to weld a surface of 12 x X mm, where “X” denotes a variable surface size. In this way surfaces are more quickly bonded than is possible with, for example, a laser scanner. The system can also create a third beam geometry, namely a contour weld of width 5-12 mm.

Applied to continuous material in a roll-to-roll process, the laser beam head can also generate a continuous weld seam. This also highlights the advantage of gentler line welding: Heat is generated more slowly along the line (linear intensity distribution) than in the case of laser spot welding. At the same time, the strength of the weld is not impaired. The advantage: heat-sensitive materials or components are not distressed by the welding process.

Usage in industrial manufacturing

The new laser beam head allows the processing of large as well as small and fragile components such as membranes, opening up new possibilities in design and functionalization. The processing head can be integrated into the manufacturing process inline and can be deployed on a robot arm. The welding process is monitored by an integrated measurement and control system. Processing data are stored to enable track and trace.

LIMO has vast experience in laser welding for car bodies and components encompassing for more than 40 different assembly groups in the car interior, exterior, the cockpit, under-the-hood parts, lighting elements, etc. LIMO’s industrial laser systems have also been successfully utilized in the medical and electronics sectors.

Laser polymer welding is an industry-compatible and product-friendly bonding technology that produces tough yet aesthetically pleasing weld seams. Processing is clean and contactless. The bonding surface does not have to be pre-cleaned, post-cured or processed in any way. It is particularly suited for sensitive materials, for optically demanding surfaces, for very precise weld seams or for very short cycle times. Containers manufactured using laser welding (e.g. to hold fluids or to house sensors) display a very high density, with a burst pressure of 10-30 bar. Electronic parts are not impaired by the welding process. Furthermore, diverse combinations of materials can be processed, such as PMMA/ABS, PC/PBT, PP/TPE as well as glass fiber-reinforced polymers.

The “LPH-L” processing head has proved itself through comprehensive field trials and is available ex stock for immediate delivery by LIMO.