Packaged with care

Foodstuffs must be packaged precisely, safely and carefully. When positioning or spacing products, it is particularly important to avoid flattening or damage during the packaging process.
The “Dynamic Stocker” accumulator made by the French firm Euro Cri converts an irregular product flow at the output of a production machine into a regular flow, as found when packaging biscuits, for example. The accumulator gathers the unpackaged products as they arrive and creates a “buffer store”, which can be regulated according to the change in the material flow.
The greatest challenge was to arrange the packaging process so that it was 100% synchronous with the rhythm of the existing horizontal flow-packer. The flow-packer forwards incoming products in an irregular sequence. Development and design demanded an automation solution capable of controlling complex movements and handle various transport speeds simultaneously. The focus was on the movement of a total of six axes. It had to be possible to coordinate the axis movements with 100% accuracy, so that the various speeds at different points of the conveyor could be synchronised precisely and safely regulated.
Euro Cri opted for a Pilz motion control solution (PMC), which enables precise synchronisation of the respective motion processes.

Complete packaging solution
As a supplier of complete automation solutions, Pilz France supported Euro Cri from planning and development to implementation and commissioning.
The central element of the motion control solution is the controller-based PMCprimo 16+, which performs the complex motion and control functions.
Used in conjunction with the servo amplifiers PMCtendo DD and servo motors PMCtendo AC, the result is a drive solution which can react flexibly to different format specifications and can be used to implement high cycle counts with ease. The absolute position of the motors can be read during operation, after the machine is shut down or after power failure. Systems with PMCtendo are modular and expandable. As a result, users can react flexibly to product changes. In addition to simplifying positioning and storing motion tasks, the PMCtendo DD also provides the power supply and motor drive on the “Dynamic Stocker”.

Packaging process is safely monitored
The packaging process can be monitored and regulated using PMIvisu operator terminals. The motion curves relevant for the cycle are calculated in the simplest way possible: the operator simply enters the set data on the operator terminal – the packaging length and the position of the section to be embossed, etc – and the system automatically calculates the motion profile for runtime. Adjustments are made via the operator terminal, whereby the material flow control system fulfils different product type requirements. The display can be used not only to select recipes but also to view error messages. The cause of the error always appears first; at the touch of a button the operator receives specific instructions on how to rectify the error.
Safety-related functions such as emergency stop, emergency off, or safety gate monitoring on the “Dynamic Stocker” are monitored via the compact safety relay PNOZsigma. The PSENmag safety switch was incorporated into the safety gate to ensure the packaging process is not interrupted unnecessarily; it is suitable for the very highest hygiene requirements and provides one hundred per cent protection against defeat.
“With Pilz we have gained a competent partner in the automation industry. We will continue to work with them in the future to develop leading-edge packaging systems for our customers,” says Mathieu Carie, Head of Automation at Euro Cri.



Author: Yannick Le Héno,
International Sales
Market Development
Pilz GmbH & Co. KG