In the assembly hall of A+F Automation und Fördertechnik GmbH, countless motors, drive mechanisms and vacuum-based grippers create a polyphonic background noise. For a well-known delicatessen producer, a 25-metre-long sort packer is undergoing final test runs before being dismantled into modules and reassembled and commissioned at the customer's premises. The modularly designed system repacks trays filled with delicatessen salads by type so that they are presented in the supermarket as a „colourful“ mix on the tray or on the shelf. A safety solution from Pilz ensures the necessary safety in the process.
A+F has equipped the Sortpacker with a modular hybrid safety solution consisting of a higher-level process control and safety control system. One Economical, functionally coherent overall solution, which the packaging machine manufacturer only offers in this form for Mushroom found. This safety solution offers optimum protection in combination with the decentralised PDP67 field distributors and the new safety gate system PSENslock 2, Reduces wiring effort and saves space in the control cabinet. The hybrid security concept also strengthens the security aspect, as it makes manipulation and unauthorised data access more difficult.
End-of-line packaging is a task with many different aspects
The cartons with the individual, unmixed delicatessen salad tubs are fed in via six lateral roller conveyors. As they enter the system, installed cameras recognise the contents and position of the respective tubs. Six Vacuum-based flexpickers suck in the containers and place them on a conveyor belt. Meanwhile, the empty cartons are placed on a parallel belt and manoeuvred to their pick-up position. When the Cups in a new assorted formation the transfer point, a handling module goes into action and places them in the trays that are now ready. The vacuum suction cup of the carton erector then removes blanks from the stacking magazine, folds them as required and covers the delicatessen salad cups in the trays. In order to take up as little space as possible in the outfeed area, a stacker picks up two trays at a time, positions them on top of each other and places the set on a gravity roller conveyor. At the end of the conveyor, the trays are ready for manual removal.
Flexibility and sophisticated security concepts
Operators of packaging systems often demand maximum flexibility and efficiency. The machines, which are generally highly automated, therefore require Sophisticated security concepts. These should effectively protect personnel from the risk of injury. However, they must not restrict operability or productivity.
Founded in 1974 and based in Kirchlengern, Germany, A+F develops and produces High-quality packaging machines. Since 2017, A+F has been part of the international group of companies EOL Packaging Experts GmbH, which offers end-of-line packaging machines and systems. In addition to the actual mechanical engineering, the entire group stands for the Assembly and commissioning of automated end-of-line solutions in the packaging industry.
The company offers a comprehensive portfolio of machines and systems for a wide range of packaging applications. In addition to standard machines, the portfolio includes customised systems including innovative handling solutions.
Trusting partnership for secure investments
Modular design, Easy-to-use safety and industrial security solutions have always been a high priority at A+F. For many years now, we have been working closely and in partnership with Pilz, the experts in safe automation.
„The integrated solutions and expert advice from Pilz not only make our systems particularly safe, but also easy to operate and convert. And therefore more competitive overall. With a strong reputation in the packaging industry and worldwide support, Pilz is our customers“ preferred supplier for safety and security."
Michael von Zmuda, Head of Engineering at A+F Automation und Fördertechnik GmbH
In line with technological progress, the requirements for efficient and intelligent safety solutions have also increased at A+F. Safety updates always go hand in hand with an increase in productivity, efficiency and a further reduction in downtimes. This is why A+F's systems today are equipped with the far More powerful and configurable small controller PNOZmulti 2 of the supplier, after the tried-and-tested PNOZmulti Classic from Pilz had been responsible for safety for many years. It ensures greater productivity, efficiency and further reduced downtimes.
Safe sensor technology for efficient processes
(Image: A + F, Pilz GmbH Co. & KG)
On the modular Flexpicker from A+F, feed and removal openings, carton and blank magazines as well as doors and bonnets typically need to be protected with suitable guards. On the infeeds and outfeeds as well as on the maintenance doors Intelligent sensor and light curtain solutions protect operating personnel reliably prevent fingers or even hands from becoming trapped. The safety gate system PSENslock 2 secures a total of twelve doors on the A + F machine with a locking force of 1000 N each. The focus here is on Protect the system from improper access and avoidable system downtimes. If access is actually required, the operator requests access via the display. The Flexpickers then move to their home position. Only then can the doors be opened. This saves time, as the system does not have to be laboriously moved back to the starting position, which minimises the operator's workload. Process flow more efficient makes.
The respective solenoid interlock PSENslock 2 is connected directly to the safe decentralised input modules field distributor PDP67 via plug & play with pre-assembled cables. A decentralised module can collect up to four PSENslock or emergency stop signals. A PDP-Link module (communication module to the field distributors) connected to the PNOZmulti 2 processes up to four field distributors in one line. Ergo: The Repackaging system actually only requires one cable from the control cabinet, to control and evaluate 16 PSENslock 2.
The pre-assembled cables serve the plug & play concept and help to reduce installation and commissioning times. For example, the signals from the TÜV-certified solution from Pilz for monitoring the cardboard blanks on the Flexpicker can also be processed via PNOZmulti 2.
Modular and flexible
The selected security solution goes hand in hand with a efficient diagnostic management The software logic in the PNOZmulti 2 analyses which door is currently „open/locked“ or which emergency stop is activated. The Pilz diagnostic system PVIS supports the plant operator with diagnostic messages, which appear as plain text on the unit display of the PNOZmulti 2 in the control cabinet. This enables them to rectify faults quickly, which contributes to more productive processes.
For the entire system, A+F relies on the Communication via ProfiNetThe ProfiNet module reports the current status of the safety controller including the extension modules cyclically to the process controller. At the same time, the PVIS diagnostic data is transmitted. The status of all safety functions is therefore visible on the HMI of the process controller at all times. The fact that the processing of the safety functions is outsourced to PNOZmulti 2 in this hybrid system reduces the load on the process controller and bus communication and makes it easier to control the process. Higher cycle times in the process possible.
„The modular design guarantees us maximum flexibility; we only pay for what we actually use. With the PDPs in the field, we reduce the wiring effort and save space in the control cabinet. At the same time, we provide our customers with simple and flexible diagnostic options.“
Michael von Zmuda
Realisation made easy
The PNOZmulti Configurator software tool can be used to Configure safety circuits intuitively with pre-assembled modules and functions. Changes to the configuration are always possible and can be traced at any time via the checksum stored in the programme (in PNOZmulti: CRC checksum). The intuitive graphical assignment of safe function blocks makes parameterisation and commissioning logical and failsafe.
The hybrid structure of the chosen safety solution is of central importance to A+F: both system manufacturers and operators can change process parameters at any time or, for example, restart the process control system - the safety control system remains unaffected. Michael von Zmuda summarises:
„We have really only found such a convincing, flexible Safe & Easy complete solution, which combines safety, configuration and operability such as diagnostics and cabling in an exemplary way, at Pilz!“
