Container closure with anti-nesting ribs

Abstract

Disclosed is a plastic injection molded closure having a plug-like section and an outer skirt. The plug-like section includes a vertical cylindrical wall having upper and lower annular nesting surfaces for nesting containers in a stack. An annular top wall outwardly extends from the vertical cylindrical wall upper end and a skirt depends downwardly from the outer periphery of the outer top wall. The lower free end of the skirt includes a bead defining a thick cross-sectional area on the skirt for engaging the upper flange of a container when mated therewith. The container upper flange extends outwardly and downwardly from the open end of the container and has a free end engaging the bead on the closure skirt. A plurality of radially inwardly directed ribs extend from the cylindrical wall and present upper surfaces to a superimposed closure that may be stacked therewith. The ribs, and particularly their upper surfaces prevent penetration of a superior closure into a cavity formed by the cylindrical wall, and thereby prevent wedging engagement with the superior closure and at least the upper portion of that cylindrical wall. The upper rib surfaces are located interiorly within the cavity and do not interfer with the long outer vertical plug sealing surface that engages the container.