| 摘要 |
The blocking element comprises a hollow central cylindrical housing situated, from the sealing membrane, as an extension of the head. This hollow housing covers the opening of the receptacle and its adjacent external wall. This overlapping shape has the advantage of avoiding the risk of adherence of blood by reducing the contact surface of the blocking element with the contents of the receptacle to the single membrane (10). It has in its internal surface an axial groove (32a) and two annular grooves (30a, 30b). The axial groove intersects the annular groove (30b) and has, at the point of intersection, a cross-section greater than that of this annular groove. When the blocking element is in the position of overlapping the tube, there is thus obtained, according to the level of engagement of the tube inside the hollow housing, a first position which is that of ventilation, then, by engaging the tube further, a second position which is that of leaktight closure both to liquids and to the external atmosphere. The head of the blocking element comprises, on its upper face, a flexible wall passed through by a diametral slot (12), whose edges constitute deformable lips (14). This slot gives access to an internal chamber (13) and terminates towards the periphery in radial cutouts (11a, 11b). <IMAGE> |
