Snap on twist off tamper-proof closure for containers

Abstract

A flexible closure for a container, such as a blow molded jug, having a neck surrounding an opening therein and a pair of vertically spaced fastening configurations on the exterior thereof, the closure having a cap portion with an annular ribbed flange and a tear skirt depending from the annular ribbed flange, the tear skirt having a pull tab for the removal thereof, the cap portion having an annular flange therein and the ribbed flange having an annular groove therein defining a frangible wall joining the ribbed flange and the tear skirt. The annular flange in the cap portion seats under one of the fastening configurations on the neck of the container and the annular groove in the annular ribbed flange receives the other fastening configuration on the neck of the container to form dual fasteners, either one of which is capable of holding the closure on the neck portion of the container. A pair of circumferentially spaced thread-like ribs are formed on the inner surface of the ribbed flange and a pair of circumferentially spaced thread-like ribs are formed on the outer surface of the neck portion of the container. When the tear skirt is removed, the opposite sides of the ribbed flange of the flexible closure may be moved inwardly to engage the thread-like ribs so that twisting the closure removes it from the neck of the container.

Dependencies are inferred from the claim text.