Tamper indicating closure

Abstract

A unitary, integrally-formed, molded plastic closure used to seal containers having threaded necks and a radially extending collar situated therebelow. Closure includes internally threaded cap, plurality of tongues spaced about lower periphery of cap, frangible tamper indicating ring spaced axially below lower periphery of cap, and a plurality of thin webs interconnecting the ring and the tongue. Closure is advanced over the threaded neck on container by automated machinery so that ring abuts against collar on container. Indicating ring includes weakened area to allow limited radial expansion, and an inwardly extending radial flange may be defined at upper end of ring. Lugs are formed on periphery of tongues. After ring abuts against collar, continued advancement of the closure along threaded neck (1) shears the webs and frees the tongues from the ring; (2) subsequently enables the tongues to engage and enter the ring in serial fashion, and (3) resiliently interlocks the ring and the tongues. The interlocked continuous ring and tongues connotate that the closure has been seated for the first time and that no attempt has been made to disturb the contents of the container. Subsequently, when the closure is removed by advancing same over the neck of container in the direction opposite to the seating motion, the threads on container radially expand the tongues and interlocking ring, thus fracturing the tamper-indicating ring at weakened area. Ring falls free of the cap to reveal at least some of the tongues and serve as a visual indicator that closure has been opened at least one time.