Package verification and presence/absence detection
Cermex — Perfect packaging at 150 products per minute
The pharmaceutical division of an Irish company manufactures the liquid that is injected during MRI scans. This product, which is expensive and sensitive to light, is packaged in small flasks/containers and is placed in special crates for maximum protection. In order to inspect this packaging, Cermex, specialist in end-of line packaging machines, chose vision technology. A Checker® vision sensor and an In-Sight® vision system from Cognex verify the number of flasks placed in the crates as well as checking for the presence of a document in each one.
The flasks containing the liquid are sent to a WB45 wrap-around packing machine where they are packed in boxes in batches of 12 or 18 depending on the box format. This machine is specially developed by Cermex for sizing the carton, packing the flasks, folding and preparing the boxes, inserting the information leaflet as well as closing and sealing the boxes… all at a speed of 150 products per minute.
Find the leaflet — regardless of its position
Both Cognex vision systems are integrated into the machine and intervene at 2 different stages. Firstly, at the packaging post where Checker verifies the number of flasks present in each crate by detecting the presence or absence of the bottle tops. Then before the final packaging, an In-Sight vision system checks for the presence of the information leaflet in each of the cartons passing on the line. This is not a simple operation. The position of the leaflet in the box is completely random, the document can slip during the process and end up flat or on its side anywhere in the box. To ensure its presence, the vision system needs to be able to find it regardless of its location or the box size. In-Sight relies on the localization tool PatMax®, powerful software capable of meeting this challenge despite difficulties and inconsistencies in lighting, a constant challenge in vision applications and an inevitable issue on the factory floor. When there is a problem, such as the absence of the leaflet or a flask, In-Sight and Checker send a signal to the PLC which releases a trigger causing the machine to stop.
"We opted for a 100% vision solution for several reasons," says Jean-Marc Passemard, Operational Marketing Manager at Cermex. "The technological homogenity of the two inspections, the space-saving qualities of the products as well as great value for money. Not to mention the fact that Cognex has a strong international reputation, which reflects well on us as a company."
Easy integration for the end-user
When integrating vision systems into the packaging machine certain ergonomic constraints needed to be respected in order to maintain easy access to the machine for operators and ensure that the Cognex systems interface well with the PLC controlling the packer. Size changes (flask size and carton size) are also automatically managed by the PLC, so camera and lighting position do not need to be manually modified.
According to Stéphane Faivre-Duboz, sales engineer at Cognex: "This application demonstrates all of the advantages to be had by modern vision systems: integration, compact, the capacity and flexibility necessary to handle high speed production and adapt to non-stop production."