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Motion Control System Controls and Automates Packaging Machines
Pilz Automation Safety L.P.
Overall motion management
Packaging machines in the pharmaceutical sector are demanding: they have to be reliable, modular and versatile, but most of all they have to be flexible and efficient. The requirements of the corresponding drive and automation system are equally high. Pilz motion control manages the movement of all the servo axes to ensure that complex workflows from infeed to cartoning do not fall out of sync and so that products can be switched at the touch of a button.
With impressive speed and the rhythmic sounds of all these simultaneous processes, foil-packaged tablets stream out of the machine on four channels at once. The machine operation is fully automatic; the actual packaging process is barely visible to the eye. Within seconds, knives transform the endless sheets into manageable sizes, which then find their way into standard cartons with the package inserts included.
Tablets in the morning, maybe capsules in the afternoon, but both need to be sealed on the same machine. Packaging on pharmaceutical products calls for innovative concepts, the wide range of products and packaging sizes demand flexible solutions. Stored process parameters mean that packaging machines can be changed over quickly at the touch of a button, guaranteeing cost effectiveness. Each system must be modular and easily expandable according to need; what’s more, only those plant sections that are currently in use should be active.
As a subsidiary of the international company Romaco-Pharmatechnik GmbH, Romaco develops packaging machines specifically for the pharmaceutical industry. Part of the product portfolio of the Karlsruhe, Germany-based company includes heat sealing machines, which seal pharmaceutical products in film so that they are air and moisture-tight and provide a perfect fit for the relevant shape. The company offers a flexible selection of machinery covering a wide range of functions in accordance with individual customer requirements.
A key component of a versatile packaging machine designed for a variety of tasks is a sealing roller with an asynchronous motor, which sets the timing for all subsequent axes via incremental encoders. A conveyor system feeds in the product for packaging, which is then inserted synchronously into the sealing roller. The heated sealing rollers take the liner material from rollers on both sides, forming an airtight enclosure around the pharmaceutical product. Servo motors drive the axes on a packaging machine. They guarantee a rapid reaction to changing process parameters and therefore a high degree of flexibility in production.
Pilz motion control (PMC) is responsible for the reliable, synchronous, fully automatic control and coordination of the individual drive axes and motion elements on the heat sealing machines. Precision is the trump card. For example, the intelligent control and automation solution ensures that the imprint on a pre-printed seal is always positioned in the middle of the tablet pack, or that the lengthways and crossways cut on the packaged product always separates exactly in the middle of two tablets, and that the perforation blade puts the tear line needed to separate individual tablets exactly where it belongs, to within a tenth of a millimeter. Any variations in dimension due to varying fill quantities are adjusted automatically by the controller during operation. “The automation system manages all the movements of a large number of physically separate servo axes within a plant or application”, explains Harald Dietel, Head of Product Management at Pilz. In addition to the original motion control tasks the system also undertakes the machine’s automation in conjunction with the integrated PLC.
There are two different types available: You can either employ the drive-integrated PMCprimo Drive (up to nine axes) or the controller-based PMCprimo 16+ (up to over 100 axes), depending on the number of axes used. PMCprimo Drive is integrated directly within the motor amplifier and can incorporate up to eight additional drives. At the same time it performs the task of a central controller. In this configuration the system contains everything required for the complete automation of small or medium-sized machinery, such as the packaging machine described above. PMCprimo Drive works economically right from the first axis; it reduces the amount of wiring involved and saves space within the control cabinet. If you need to control more than nine axes or larger plants, the PMCprimo 16+ is the system to choose as a central controller. It can be used to implement complex motion and control functions with well over 100 axes. Servo amplifiers, servo motors, panels and many other components required for automation technology help to round off the system.
Whether you are planning a new design or a retrofit for your machine, whether you want a small machine or need whole packaging lines equipped with infeed, packer, cartoning station, palletizer or pick-and-place: both the drive and controller based solutions offer the optimum hardware basis for any application. Pilz motion control is expandable, remaining open and flexible to developments of any type.Both versions have something in common: less work is required during implementation and programming. Numerous function blocks for automating axis movement are available and ready to use. To activate functions such as “cross cutting” for example, just start this up from the menu and set reasonable parameters. The system will detect any implausible combinations and not allow them.
There was a whole range of reasons why Romaco Siebler opted for Pilz motion control for their heat sealing machines. “Simplicity and expandability were the convincing arguments. Because of the large number of compatible functions, it took hardly any effort to implement the entire system, and that includes parameter setting and diagnostics”, stressed Martin Schneider, electrical design engineer at Romaco Pharmatechnik GmbH in Karlsruhe. Selection was made even easier by the compact design and the fact that both control and automation functions are included in one system and are from one source. “Competent advice and project backing convinced us that we made the right decision” added Jürgen Kratzmeier, Technical Manager at Romaco Pharmatechnik GmbH.
Pilz wants to go one step further in the future: The plan for the next controller generation is that it should combine the various requirements of standard control technology, safety technology and motion control in one system.
Pilz is a global company, as such, not all standards and information will be applicable worldwide. Please check with your local Pilz office to ensure your factory and/or machines meet local standards.