Method and apparatus for utilizing a shadow effect for counting newspapers, magazines, books, printed products, signatures and other like printed matter

Abstract

Printed products, such as newspapers are fed past a counting station arranged in imbricated fashion, preferably folded edges passing downstream first. A high intensity light source is arranged so that its light beams are oriented at an angle which, while illuminating upper surfaces of the newspapers, causes the forward folded edges to cast a shadow upon the upper surface of a downstream newspaper that the forward edge of the newspaper creating the shadow rests upon. An image sensing device creates an image of a given region which includes the leading edge of the newspaper creating the shadow. This image is compared with stored criteria to determine if the 'shadow' is due to a leading edge of a newspaper and to thereby discriminate a newspaper leading edge from other spurious conditions which, although they may create a 'shadow', fail to meet the criteria of a leading edge of a newspaper.