METHOD AND APPARATUS FOR THE MANUFACTURE OF INCORPORATED CLOSURE CARDBOARD TUBES FOR PACKAGING OR SHIPPING ARTICLES OR DOCUMENTS, AND TUBES OBTAINED BY CARRYING OUT SAID METHOD

摘要

P THE PROCESS INCLUDES CONTINUOUS FORMATION OF A CARDBOARD TUBE ON THE TURNING CHUCK OF A SPIRAL AND THE CUTTING OF THE TUBE IN TUBE ELEMENTS 17, 18 EJECTED BY THE MACHINE. THIS CUTTING IS PERFORMED ACCORDING TO A SINUSOID-SHAPED CUT WITH THE APPROPRIATION OF APPROPRIATE FOLDING LINES 24, 25. THE TUBE ELEMENTS 18, 17 WHERE THE ENDS HAVE TWO OPPOSITE TABS 21, 22 FOLDABLE, THE ENDS ARE OBTAINED WITHOUT LOSS OF MATERIAL. ADJACENTES OF TWO SUCCESSIVE TUBE ELEMENTS BEING DEPHASE OF 90. / P P The invention relates to the production of cylindrical tubes in cardboard for the dispatch of documents. / P