The device is of the type having a stacking drum with openings in its cylindrical periphery by means of which the articles to be conveyed can be adhered by suction to the drum and accumulated in an orderly stack, with the suction air being effective only within a predetermined circumferential range of...http://www.google.fr/patents/US4073487?utm_source=gb-gplus-shareBrevet US4073487 - Discharging and stacking device for flat articles
