Closure fastening means

Claim 1

A hollow plastic plug for fitment to the mouth of a container having a substantially rectangular mouth, said plug having: a. a substantially rectangular cross-section with a long side and a short side; b. a top wall having an opening extending in the direction of the long side of said plug from the short side thereof; c. a skirt downwardly depending from said top wall and adapted to obtain said fitment, said skirt having a stepped portion for bearing on the edge of the container mouth upon fitment of said plug to said container; d. a flap, adapted to close said opening, integrally formed and hinged to the top wall at the end of said opening remote from said short side, said hinge extending along a line perpendicular to said long side; e. a recess in said plug adapted to receive the free end of said flap in its closed position; and f. a cooperating snap-action means integral with said plug and having a first portion on the bottom surface of said flap at its free end and a second portion disposed adjacent said recess, said first and second portions having complementary coupling surfaces extending in a direction perpendicular to said long side of said plug, and said second portion having, i. an inwardly extending horizontal wall, ii. an inwardly and downwardly directed beveled wall depending from the innermost end of said horizontal wall, iii. a second horizontal wall inwardly extending and spaced downwardly from the lowermost extent of said beveled wall, and iv. a vertical connecting wall connecting said lowermost extent of said beveled wall to the innermost extent of said second horizontal wall, and said first portion having, v. a downwardly extending vertical wall, said vertical wall having a downward extent approximate the vertical distance between said first and second horizontal walls, vi. a latch wall outwardly extending from said vertical wall to an extent such that when said vertical wall and said connecting wall are in contact said latch wall extends beneath said second horizontal wall, and vii. a downwardly and outwardly extending wall connected at one of its ends to said top wall and at its other end to said latch wall.