Ultrasonic plastic welding of automotive interiors

1 min read

Ultrasonic technology continues to be adopted as the process of choice for a growing number of plastic welding applications, many of which are within the automotive sector. The precise control, and resultant consistency in the process, makes it the ideal solution for joining and welding a wide range of polymer types and component variants, according to OEM Telsonic.

In a recent application by Poole-based Telsonic UK, “B” pillar products for the new Land Rover Defender are assembled using the company’s ultrasonic technology by KASAI Slovakia.

The system, designed and built by Telsonic UK and shipped to Slovakia, is used to weld left and right hand B pillar assemblies joining the seat belt cowls to the polypropylene pillars. Correct assembly is assured through the use of sensors to detect that all parts are in place, including the cowl, main pillar substrate and the airbag cover.

The machine also senses two colour variants of each of the three parts and also checks that metal clips and black felts are in position using a combination of inductive and camera sensors. Quality limits are also set for both weld delivery and collapse of the weld features.

The individual component parts are manually loaded into PU nests mounted onto an Indexing table, with the parts being secured within the nests by swing clamps.

The weld features are tubular staking pins and are formed to JLR weld specification by four Telsonic manufactured twin Titanium mother-daughter sonotrodes, fixed to four Telsonic 35kHzAC450 actuators complete with SE3512C converters including integrated cooling. The sonotrodes are powered concurrently by four TelsonicMAG3512E generators, selectable for Right or Left hand part only weld operation if necessary. Weld cycle time is 15 seconds per pair of “B” pillars.

The machine is guarded with Keyence light guards and painted and finished to Kasai Slovakia’s strict site requirements and specifications. In addition, the HMI and manuals are dual language.

Bar code labels are printed for left- and right-hand parts, only if all component parts are sensed as being present and the weld quality meets the pre-determined thresholds. A further check is then made to verify the position of the bar code label. The component parts are only released from the clamps if all of the above criteria are met.