Center shot sorting system and method

Abstract

A system and method for sorting items (16) computes the geometric center ('centroid') (156) of any item containing a defect (26) or multiple defects, and directs an ejection air blast at the centroid of the defective item rather than at the location of the defect. Video data from a scanning camera (24) are transmitted to an 'item processor' (32A') and a 'defect processor' (32). The item processor builds in memory (108) an image of every acceptable or defective item while the defect processor builds a 'defect list' (170) of defect coordinate locations detected only on defective items. The defect processor transmits the defect list to the item processor where the defect list is compared with the stored image of the item. For each item containing at least one defect, the item processor computes a defective item centroid that is added to a defective items list (174) for use by a defect removal process that actuates air blasts directed toward the centers of defective items. Air blasts directed toward the centroids of defective items maximize their deflection and minimize item spinning and thereby improve item rejection efficiency and reduce the inadvertent bumping of adjacent acceptable items toward the rejection conveyor. If multiple defects are detected on a single item, a single air blast is directed at the centroid of the defective item.