Speed is key in battery production. Varta Consumer Batteries GmbH & Co. KgaA in Dischingen, Germany produces up to 1 billion portable batteries annually. In order to meet customer demands for product quality, the company relies on a high level of automation. Varta has strict tolerance limits for battery production, specifically for the interfaces for energy transfer (i.e., the plus and minus poles). Batteries that have mechanical faults or performance defects must be rejected. However, Varta is also concerned with preserving production efficiency and containing costs, so it is also important to keep the proportion of rejects as low as possible. Varta selected aku.automation vision systems featuring VisionPro® 3D software and a 3D camera. They have succeeded in achieving 100% fault detection and minimum rejection of acceptable parts on seven production lines with this vision system in place.
A small but major difference
Until the introduction of industrial vision systems, humans inspected products for possible mechanical defects. In 2010 Varta started using 2-D vision to detect quality defects caused by contamination and mechanical distortion rather than personnel. However, these systems identified pseudo-rejects at an unacceptable rate of 8 -10%. Even the smallest particles of contamination, which had no negative effect on either the battery's performance or appearance, were graded by 2-D vision systems as defects.
aku.automation solved this problem using a 3-D camera, in combination with powerful VisionPro® 3D software. This new system made differentiation between contamination and mechanical distortion easy and reduced the pseudo-reject rate to an acceptable level.
Performance without limits
In the process of testing the 3-D vision system, Varta used VisionPro 3D software to compile an extensive reference sample catalogue. Varta is able to successfully differentiate between contamination and mechanical defects, thanks to the VisionPro 3D histogram and blob analysis tools, among other things. VisionPro 3D’s multi-processing capabilities deliver the high speed application support that Varta requires and VisionPro 3D allows the 3D system to make use of the full capacities of modern multi-core devices.
Room for success
For Varta, the newly acquired 100% testing/inspection quality provides an additional product differentiator in a highly competitive market. And not least, the minimized rejection rate is making a vital contribution to the long-term future of the production facility.