METHOD FOR KEEPING CLEAN AN OPTICAL PASSAGE IN THE OPTO-ELECTRONIC DIMENSIONAL MEASUREMENT OF ROLLED CROSS-SECTIONS IN A CONTINUOUS PRODUCTION PROCESS

摘要

The optical channel (8) is maintained clear of dust etc. by using annular jets (2, 4) on either side of a measuring gaps (9) through which the rolled product is fed. The jets and the gap cooperate to providee a section force in the rolling direction which draws the dust particles away from the optical channel (8). Pref., the optical channel has a light source and a photodetector on opposite sides of the rolled product each protected by a respective optical window.