Closure with an elastically deformable element

A valve configured for opening and closing a filling-emptying channel operatively connected to a liquid holding container, comprising:

• A) a valve body, including:
• i) an annular inner surface, wherein the annular inner surface bounds the filling-emptying channel, has a shape of a truncated cone with a base inward relative to the container, and wherein the annular inner surface includes a largest inner diameter, ii) a ring, wherein the ring includes a boss and a hole, wherein the boss and the hole are centrally located relative to the annular inner surface, and iii) at least two arms, wherein the at least two arms operatively connect the annular inner surface and the ring;
• and B) an elastically deformable valve plate, wherein the valve plate includes:
• i) an outer circumferential edge, wherein a plate diameter of the valve plate at the outer circumferential edge is greater than the largest inner diameter, ii) a centrally located inward extending conical part, configured to extend in deformed engaged relation in the hole, and iii) an area of circumferentially outwardly narrowed thickness;
• wherein in blocking relation of the filling-emptying channel, the conical part extends in the hole and the outer circumferential edge extends within and in engaged relation with the inner annular surface, whereby the valve plate has a convex cup shape, and wherein force applied outwardly on the valve plate is operative to cause the conical part to disengage from the hole and the area of circumferentially outwardly narrowed thickness to change convexity, whereby the valve plate is disengageable from the valve body to open the filling-emptying channel.