Winding inspections of foils on a roller

Description

An inspection is performed lengthwise across a roller to determine whether foil has wound on the roller. In the event of winding thicknesses of greater than approximately 2 mm, winding would lead to severe machine damages. Up to now, a laser throughbeam photoelectric sensor was used. This was, first of all, difficult to align and, second, led to false switch-offs due to vibrations during operation. For this reason, a more reliable, more easily alignable sensor solution with a non-divergent light beam over the entire roller width of approx. 1.2 m was sought.

Solution

The PRKL 25B laser retro-reflective photoelectric sensor with polarization filter and the matching MTKS 50x50 reflector are used. With this photoelectric sensor and the reflector, an optimum solution was found that ideally satisfies the requirements for large range and simple alignment.