Safety cap for threaded closure

Claim 1

A safety closure for containers having external threaded openings, said closure comprising the combination of an internally threaded inner closure member adapted to be threaded onto the externally threaded opening of the container to close said opening, said inner closure member and said container being shaped to form an open space directly beneath at least the outer peripheral portion of the bottom of said inner closure member when said member is threaded onto said container, said inner closure member also forming a plurality of recesses in the outer side wall thereof, an outer closure member fitted over said inner member and freely rotatable relative to said inner member to normally prevent rotation of said inner member, the top of said outer member overlapping the top of said inner member and the bottom of said outer member forming a flange extending radially inwardly beyond the outer periphery of the bottom of said inner member in said open space to hold said outer member captive on said inner member, the axial dimension of the internal space between the top of said outer member and said flange being substantially greater than the maximum axial dimension of said inner member to permit limited axial movement of said outer member relative to said inner member, said outer closure member forming a plurality of lugs projecting inwardly from the inner sidewall thereof, said lugs being axially spaced away from the recesses in the outer sidewall of said inner member when said outer member is in its lowermost position where said flange is spaced away from the bottom of said inner member, said lugs also being normally radially spaced away from said recesses at any axial position of said outer member relative to said inner member, said lugs being located for axial alinement with said recesses when said outer member is in its uppermost position where said flange engages the bottom of said member, the sidewalls of said outer closure member being sufficiently flexible to permit said lugs to be pressed into said recesses when alined therewith to provide latching engagement between said inner and outer members whereby said inner member may be rotated to remove the closure from said container.