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SENSORS...

Contrast sensors ensure labels

are aligned on boxes of sweets

During high-volume production of confectionery, sealed cartons of bagged candy
travel by conveyor to a labelling station. Contrinex’s versatile and high-performance,
RGB light-based photoelectric contrast sensor checks the label’s alignment and
confirms the presence of print registration markings. If a label is blank, illegible or

wrongly positioned, the carton is diverted to a holding area for investigation
n the food-processing industry, packaged the carton. From time to time, misfeeds or
consumer products require labelling – both for malfunctions occur within the printer-applicator,
identification and for batch control – before which consequently applies labels that are either
Ifinal packing. During confectionery production, blank, illegible or wrongly positioned. Failure to
sealed cartons of bagged candy travel by conveyor detect these errors results in unidentified or
from carton-taping stations to a label printer- untraceable products arriving at subsequent
applicator, before passing to the final packing area. operations or, critically, at the customer’s premises.
The printer-applicator, which is located at one A highly reliable non-contact sensor system is
side of the conveyor, produces a continuous feed of needed. The sensor must detect the alignment of
printed labels from roll-stock. As each carton passes labels and confirm the presence of print markings as
the applicator head, the label-stock advances, cartons leave the printer-applicator, rejecting any
peeling a single label and applying it to the side of defective cartons.