Digital Packaging Machinery: Communication by Data Transfer

Only a few years ago, no one would have guessed at the rapid pace at which the packaging machinery is going digital. We take a look at the latest trends.

10/10/05 Only a few years ago, no one would have guessed at the rapid pace at which the packaging machinery is going digital. On the contrary, it seemed that switch cabinets would need to become ever larger with the increasing pace of electronisation. Bus systems which drastically reduce the number of cables needed plus decentralised computers have meant this development has been halted. Nowadays, a freestanding switch cabinet is no longer necessary in the packaging industry. Digital packaging machinery takes up even less space than its mechanical or electromechanical predecessors.
The age of automation in the packaging industry began about 20 years ago: All-mechanical machinery was equipped with a programmable logic controller (PLC) for the logic functions and a mechanical line shaft for the drive. This first generation was, however, not very flexible. Shorter product life cycles and range diversification, especially in the food sector, prompted ever louder calls for greater flexibility. In the second generation electronic drive systems took over an increasing number of functions from the line shaft. Logic functions were still controlled by PLC systems.
Control and drive technologies proved the key technology in the packaging machine construction industry. Today, fully electronic, third generation (Gen3) machines boasting all the advantages of servo technology are setting new standards. Digital packaging machinery offers not only better output and greater flexibility but also additional features like tele-maintenance, integration into the ERP system of a company or evaluation of production data.
The logic functions formerly performed by PLC are losing their significance. Electronic motion functions now dominate. The number of servo engines is increasing with the demands for flexibility. Motion control is integrated into Gen3 controls and is no longer necessary as external PLC. This means physical and logical interfaces are no longer required as they were in the past due the different programming languages and systems. Some firms have been setting trends in this field since the mid-1990s with integrated motion control and logic solutions for the packaging machine construction  industry.
Toploading is gaining increasing popularity for packaging products in folding boxes. Flexible cartoning machinery loads the boxes from above making it much more flexible than a horizontal solution. Robot arms can be equipped with different vacuum grab heads to deal with the most varied of products. This solution is also effective for loading composite packaging: In the pharmaceuticals sector, blister packs, ampoules, bottles, package inserts, inlays or spoons can be packaged. The state of the art in toploaders will be showcased at interpack 2005 in Düsseldorf from 21 to 27 April.
In the confectionery sector, toploaders are used for the placing of various individual chocolate shapes in deep-drawn trays. The flexibility of the toploading principle also primarily lies in the large-format sector. The machinery can be adapted to new folding box shapes with just minor adjustments. This means new product types and future requirements can be anticipated.
Today, the controls for packaging machinery to cater to individual customer demands are still very heterogeneous and are characterised by the developments of individual manufacturers. Standardisation would not only make key components from different manufacturers interchangeable but would also free users of their dependence on manufacturer-specific expertise. So-called open control architecture would promote still greater flexibility here.
Internationally coordinated automation concepts are being elaborated by the OMAC (Open Modular Architecture Controls) working group for packaging machinery. Those initiating the working group were machinery users from the branded product industry who collaborate within the OMAC alongside machinery builders and technology suppliers. The aim here is to make the hardware for automation systems interchangeable in the medium term. The next step should then be to harmonise the different systems for communication between machines and to standardise the operating philosophy. An initial European OMAC Packaging Working Group symposium was held in Düsseldorf during interpack 2002.
Another trend is system solutions which allow automation technology (AT) to communicate with information technology (IT) and its standards via data networks. This means corporate information networks and vertical data integration are possible from the pilot and control stage through to the production stage. Joint communication standards facilitate the processes from diagnostics and tele-maintenance to the Internet and logistics for spare parts purchasing. This means the flow of information from digitalised packaging machinery can be utilised for more efficient production including up and downstream business processes.
With tele-maintenance the rapid exchange of information saves working time and travel costs. When mechanical malfunctions are remedied online downtime is reduced. Remote diagnosis at Bosch, for instance, makes error detection possible within the computer, at the operating interface and in the servo drive system. Changeovers to other products or packaging materials also require software adaptations that are performed via tele-servicing.
Digital packaging machinery equipped with a wireless system that can link up with external transport vehicles to control the automatic supply of packaging material is, of course, still a vision of the future.
The quality requirements in the food and pharmaceutical industry are rising with the increasing globalisation of markets as country-specific guidelines must be adhered to. This also means the requirements made of quality assurance systems such as automatic image processing are higher. Optical sensors make it possible to capture details in mass production at high speeds where individual manual inspection would not be possible. This means improved quality guarantees because the production process is monitored completely and is no longer merely subjected to random checks. The significance of constant inspection is, for instance, made clear in the production of glass bottles and containers: chips on the tops of reusable bottles make tops more difficult to open later on, quite apart from the possibility of glass chips entering the bottles. Faulty products must be reliably identified and removed from the cycle. Optical systems include operating interfaces with flexible configuration features that can be adapted to the needs of inspections.
Controls for packaging machinery are dependent on precise information from sensors. For instance, special light barriers in the field of film packaging can achieve decisive rationalisation benefits. The amount of film consumed can be reduced when the light barrier is positioned outside the oblong film bag. This makes high demands on the sensor as it must recognise the product through the film. This can pose a problem with multi-layer films, welded seams or creasing. Adaptive receivers have proven successful in such cases as these. They can adapt to the different products and film types.