device for detecting foreign substances in a kunststoffharz

摘要

A method and a device for detecting by image processing foreign matter in a resin flowing through a passage in an extrusion head of an extruder for extruding a plastic to form a plastic-covered power cable. A see-through glass window is provided at a throat portion having a resin passage having a reduced sectional area and provided in the extrusion head between a breaker plate at the leading end of a screw and a head body having a die and a nipple mounted therein. A light source and a camera are provided outside and opposite to the glass window to detect any minute foreign objects in the resin flowing through the throat portion. IMAGE