Plastic snap hinge

In a plastic closure having a first part (10) attachable to a container, a second part (20) connected in one piece with the first part (10) by a main film hinge (31), a spring element (32) which engages the first part (10) and the second part (20) and bridges an axis of rotation of the main film hinge (31) and generates a snap effect, the improvement comprising:

• the main film hinge (31) continuously extending through an area in which the main film hinge (31) is bridged by the spring element (32), and in a closed state of the plastic closure the spring element (32) is positioned completely within a continuous shell wall of the closure.

In a one-piece plastic closure for fastening on a container, having a lower part (10) attachable to the container, a cap (20) which is integral with the lower part (10) by a main film hinge (31) positioned in a pivot axis, a spring element (32) capable of generating a snap effect, the spring element (32) extending beyond the main film hinge (31) and hingedly connected at one end to the lower part (10) and at an opposite end to the cap (20), the improvement comprising:

• the main film hinge (31) extending continuously over the spring element (32), the spring element (32) having two U-shaped partial spring elements (33) extending parallel to each other and having an interspace (34) between the U-shaped partial spring elements (33), an interior surface (38) of each of the U-shaped partial spring elements (33) inclined toward the interspace (34) at least in an area of two U-shaped arches (35) of the U-shaped partial spring elements (33), such that a thickness of each of the two partial spring elements (33) tapers toward the interspace (34), and in a closed state of the closure, the spring element is (32) positioned completely within the closure.