JENOPTIK - VOTAN™ W - Laser Welding Machines
The chute channel - an important safety element.
A chute channel is a shoebox- sized frame mounted on the rear of an instrument panel. On deployment, the airbag opens into the chute and creates the necessary pressure for the airbag flap to open and for the material to tear along the designated contour. For this reason the quality of welding seam on the chute channel is a significant safety issue.
Advantages
• Quality and process control; control of the melting temperature in the seam area by means of an integrated infra-red sensor in the welding head. Because of the localised heating, the welding seam is not visible from the décor front view and there are no visible indentations
• Process flexibility – the robot controlled welding head allows a free choice of programmable welding contours without tool change
• The direct contactless application of the laser energ requires no pause between the heating process and the creation of the weld seam
• Vibration free generation of the weld seam in the airbag chute channel on the rear side of the instrument panel protects the deliberately weakened contour of the airbag flap
• Glass fibres in GFK materials in the instrument panel remain undamaged during the process
• Even with weld seams of < 0.5mm, high tensile strengths for the welds are achieved
• Compact units for combined LHD and RHD jigs (a laser on a robot with welding head)
• A gel cushion for the instrument panel protects the decor side from possible damage
Technology
Using a 400W diode laser, an airbag chute channel made of the natural- coloured and therefore laser transparent material PP-GF30 is welded on the rear side of an instrument panel made of glass-fibre reinforced PP material.
The welding head is moved along the weld contour by a robot. The laser beam passes through the optically transparent chute material and so the total energy is absorbed entirely at the required seam location on the instrument panel. A welding process lasts between 20 and 50 seconds depending on laser power.
Process control
The melting point of the plastic material is measured in real time by means of an integrated, pyrometric temperature sensor and so the laser power can be exactly controlled.
This process control thus guarantees the high quality and strength of the weld, which for a safety relevant component such as air-bag module is, a particularly desirable requirement.
Lasers welding of airbag chute channel on instrument panels
laser welded instrument panel
Application sheet - Laser Welding of chute channels