Prepared for all eventualities
Modern labelling machines with integrated servo technology offer complete flexibility for a precise container dress. Markus Müller, HEUFT Product Manager Labelling, explains the advantages.
Mr Müller, where and why is servo technology used in labelling machines?
"State-of-the-art, wrap-around labellers have a servo-controlled toothed belt so that the rotating speed of the containers can be exactly controlled and finely adjusted. Modern self-adhesive and wet glue labellers are equipped with servo-controlled rotating platforms in order to apply labels perfectly onto up to 72,000 bottles or jars per hour. They are responsible for the fine alignment of the containers with millimetre accuracy. Servo technology is also in the dispensing head of our self-adhesive labelling machines. It distributes the labels from the roll precisely there. Generally speaking this technology permits a flexible and accurate positioning of the labels. In addition servos are very efficient and economical especially when they manage without gears and have lifetime lubricated bearings – as do the HEUFT machines. This makes them practically maintenance-free and non-wearing."
Are there other advantages?
"Yes, servo labellers show their true strengths above all along filling lines with a great variety of brands particularly in the premium sector: specific container diameters require specific rotating cams. The cam of a modern servo machine is changed fully automatically whereas in the past cam segments had to undergo an elaborate mechanical replacement. Consequently program changes function within a very short time at the push of a button and considerably less change parts are needed for this. The marketing aspect is also an important argument: you never know what the Marketing Department will devise next – perhaps the introduction of embossed bottles or containers with the no label look plus special windows in the label where it is necessary to align using different characteristics. A tremendous amount of flexibility is required for this. Those who have a machine such as the HEUFT TORNADO S flex, which is already prepared for all eventualities from the outset, are at an advantage."
Do you have an example?
"The mechanical cam had to be changed completely in the past and all the brands, including those which already existed, had to be commissioned again from scratch in order to carry out the precise application of a newly introduced wrap-around label to the bottle neck. This requires a lot of time, energy and money. In contrast with servo technology only the one, newly added brand has to be extended and the cam programmed accordingly. This keeps the time and effort involved within limits."
Let’s get back to the fine alignment of the containers: how does this work?
"Using optical detection procedures and servo technology: typical container characteristics such as swing tops, embossing and even hairline mould seams are identified by camera and used as reference points for the adjustment. The servos below the platforms then rotate and orientate the bottles so precisely that the labels always remain stuck exactly in the positions intended for them. This practically excludes false positioning. The same applies to bubbles and folds which can occur e.g. when gluing over the mould seam."
Does this servo-controlled adjustment have other positive effects?
"Definitely! Orientation marks are no longer necessary; this makes the containers cheaper. The risk of glass breakage and wear are reduced at the same time. Because force is exerted during a conventional mechanical adjustment: special fingers engage in the rotating bottles. This can damage them. The fingers themselves wear out eventually. By comparison everything works completely without contact using servo technology. And where there is no contact there is no wear."
Even the servos themselves, as mentioned above, are practically non-wearing. But what happens should one fail?
"Replacing the motors is very easy. Any mechanic can deal with this in no time at all without having to call an electrician. The new servo is then programmed fully automatically at the machine afterwards."
Is it possible to combine several labelling procedures in one machine using servo technology?
"Yes, we have just installed such a flexible labeller for an important Russian fruit juice and baby food producer. The machines of the HEUFT TORNADO flex series apply self-adhesive front and back labels to bottles and tamper evident labels to food jars from above first. Their safety tabs are then folded down and rolled on neatly. Wrap-around labels are applied afterwards aligned for this purpose. This functions absolutely precisely because the servos always know the exact position of the containers as soon as the lid labels are present. In addition they ensure a fast change to another type of packaging. Because completely different rotating cams are required for the wrap-around labelling of baby food jars and the self-adhesive labelling of juice bottles. The changeover is also possible in this case at the push of a button due to the servo technology!"
Mr Müller, thank you for talking to us!