The ML20 markless sensor from Sick is designed to be used like a print mark sensor but does not require any optical marking on the package, instead detecting a taught-in design pattern.
It therefore features more flexibility and more design freedom when planning packaging and needs less set-up time when it comes to changing labels and formats, avoiding unnecessary use of materials.
The ML20, which can be used for controlling cutting edges, for example, employs a method for contrast pattern detection that involves teaching in a pattern sequence to the sensor. The pattern is detected during processing, at a scanning speed of up to 7 m/s, resulting in a switching signal. Even in the case of complex designs, tolerances in the track course of the continuous material and high machine speeds, the ML20 delivers reproducibility of up to 0.6 mm and precise and stable detection of nearly any pattern.
When changing label or film rolls, the sensor avoids unnecessary cutting loss and waste, since pattern detection is active immediately - the material can be used very soon after the beginning of the roll. Moreover, in the case of various packaging procedures, such as when labelling bottles, it is possible to save additional material that used to be dedicated exclusively to the mark.