A Closure for a Container(One action opening device with a cam system for reducing the opening force

Abstract

There is described a closure (1) for a container comprising: a pouring spout (2) having a neck (5) to define a pour opening (3) and a cover portion (6) closing one end (8) of said neck (5); a cap (4) which can be rotated about a . longitudinal axis (A) to be fitted to, and removed from, the pouring spout (2); cam means (16, 17) for transforming a rotation impressed to the cap (4) into a stroke thereof having a rotational component about the same rotation axis (A), and a translational 623 / 2011 component along said axis (A) to couple / detach the ca£ (4) with / frbm the pouring spout (2); a weakening line (9) provided on said end (8) of the neck (5); first opening promoting means (25) provided on an annular outer periphery of the cover portion (6); and second opening promoting means (26) provided on an annular inner periphery of the cap (4) and arranged for engaging the first'opening promoting means (25) upon removal of the cap (4) from the pouring spout (2) to separate the cover portion (6) from the neck (5) along the weakening line (9); the first and second opening promoting means (25, 26) comprise at Jeast one. further cam element (30) arranged aloijg an angular portion of the annular periphery of the Cover portion (6) and configured to enhance locally the lifting thrusj produced by the cap (4) on the cover portion (6) as a result of the action of the cam means (16,17) during removal of the cap (4) from the pouring spout (2).