Sorting apparatus

摘要

Optical sorting apparatus wherein during sorting, articles are directed to free fall through an illuminated inspection chamber. A light reflecting background positioned in the chamber is adjustable to form a variable reference standard of reflectivity. A sensor positioned to receive light from the background establishes a reference level and also receives reflected light from objects passing through the chamber. A change in detected light level from the reference level is indicative of a property of an article to be sorted for selectively effecting sortation of the article.