PROCESS FOR PRODUCTION OF A BOBBIN TUBE FOR YARN, DEVICE FOR EMBODIMENT OF SUCH PROCESS, BOBBIN TUBE OBTAINED AND MODE OF UTILISATION OF SAID BOBBIN TUBE

摘要

The invention relates of a cardboard tube (2) which is applied against rotatory die (10) by means of a narrow marginal end area thereof having a an interior hollow roll (7). Said rotatory die (10) is provided with a concave surface (11) that is designed to form an entrant perimetric step (13)The diamter of the that extends inward by constriction of said narrow marginal area (14). The diameter of the riser thereof is equal to the interior diameter of the cardboard tube (2). At the same time against the interior hollow roll (7) is applied a force (F)to flatten the cavity (9) of the interior hollow roll (7) and apply the wall (8) whereof against the interior face of the wall of the cantilevered end of the cardboard tube(2) formed by the action of its rotatory die (10).