Food manufacturer Knorr has implemented machine vision at its sachet packaging plant in Heilbronn, Germany to provide a quality check of the seals on the sachets. The vision system consisted of a Cognex In-Sight Micro camera, In-Sight Explorer vision software with PatMax pattern recognition technology and a Cognex VisionView 700 visualisation panel. The system was installed by Aku.Automation of Aalen, Germany.
Sporadic production errors can occur in the filling or final sealing stages of high-speed sachet production operations. Knorr requires zero errors on its production lines. The vision system has replaced a manual check at the end of the production line.
The relief of the welded seams was inspected and any material overlap or defective welds are detected immediately and the product is discharged.
Another important quality parameter is the angle the welded seam makes with the outer edge of the bag. Using PatMax pattern recognition technology, the In-Sight Micro works out the observed values, checks them against the tolerance values using an internal processor and if there is an overshoot or undershoot, it sends a not-in-order signal to the PLC, which removes that product from the process.
By cropping the pictures to only the image areas that are relevant for quality checking, the imaging experts Aku.Automation have managed to increase the evaluation rate to 840 frames per minute.
Due to the In-Sight Micro’s small dimensions (30 x 30 x 60mm), it has an extremely wide range of fitting options so that it can be used almost anywhere in the production line. The VisionView user interface display makes monitoring the manufacturing and inspection process very simple.
