Lid for a container neck provided with a thread or undercut shoulder

Abstract

A two-piece lid for closure of a container neck with a thread or undercut shoulder having a lid member formed of a metal and a separate safety ring formed of synthetic material. The ring has an upper part and lower part, with the upper part positioned inside a sidewall protrusion which is provided at the lower edge of the lid member. In order to make the safety ring undamageable, the ring can be shrinkable in its lower part. On the other hand, the upper part of the safety ring can be formed as an outwardly directed edge and the lower part can be formed as an inwardly obliquely directed lip, so that the ring has a substantially Z-shaped cross-section. In both cases, there are no parts protruding over the protrusion of the lid member, where the ring could be damage unintentionally. If the safety ring also is stressed, either by separated elongation tongues on the inside of the lower part or by deformation of the upper part of the ring obliquely upwardly into the inside of the lid member portion, the separated, torn open parts of the lower part will spread to the outside away from the container neck after opening of the lid. These torn open parts cannot be pushed back inwardly to mislead a following user of the lid that the container is still unopened. In order to push the lower part of the ring over the container neck with less effort during assembly, the lower part is provided with toothing facing and engaging grooving formed on the outer parts of the safety ring.