Sheet movement monitor in sheet processing, especially offset printing, machine, has light barrier, optically reflective surface on guide path along which light beam passes by surface light conduction

摘要

The sheet movement monitor has a light barrier with a light source (2), a light receiver (3) and a light beam (4) passing between them and an optically reflective surface on the sheet guide path (1). The light beam passes along the surface of the sheet guide path by surface light conduction. The sheet guide path is curved and the light beam passes along the concave side.