Closure for a spout of a thin-walled package

A closure assembly for a package with a flexible thin-walled bag for containing fruit juices and puree, yoghurt, and energy drinks, comprising:

• a spout unit extending along a spout axis, comprising a connection portion suitable for being hermetically applied to the flexible thin-walled bag, and a spout comprising an inner surface, wherein the spout unit further comprises at least one spout cam portion made on said inner surface;
• a closure applicable to the spout unit and comprising a cap unit comprising a cap engageable with the spout and extending along a cap axis, wherein the cap comprises a cap wall and a cap base that closes the cap wall at one end, wherein the cap unit further comprises at least one cap cam portion extending inwards from the cap base;
• wherein the at least one cap cam portion is at least partially complementary to the at least one spout cam portion;
• wherein, in a disengagement configuration, by rotating the cap about the cap axis with respect to the spout, an interaction between the at least one cap cam portion and the at least one spout cam portion causes an axial lifting of the cap with respect to the spout;
• wherein the at least one spout cam portion defines an upper cam surface inclined with respect to the spout axis and having at least one extension equal to at least one fourth of the circumference;
• and
• wherein the upper cam surface is arch shaped with a lowered center so as to define two opposite slopes and has an extension equal to half the circumference.