Closure clasp

A clasp for releasably effecting secure closure of a container having first and second portions pivotally attached to each other at a common edge, the first and second portions being pivotable into mating engagement in a closed position, said clasp comprising:

• (a) a catch fixed on the outside of the first portion of the container adjacent an edge thereof remote from the common edge;
• (b) a knob rotatably mounted on the outside of the second portion of the container adjacent an edge thereof remote from the common edge at a position opposite said catch when said first and second portions are in the closed position thereof, a projecting portion of said knob interior to the peripheral circumference thereof projecting beyond the edge of the second portion of the container to overlap the first portion of the container when the first and second portions are in the closed position thereof, and the side of said knob adjacent the container defining an underside of said knob;
• (c) a recess centrally formed in said underside of said knob;
• and
• (d) a catch channel formed in said underside of said knob communicating with said recess and extending therefrom radially outwardly into said projecting portion of said knob to terminate at a radially extreme point within said projecting portion;
• said knob being rotatable into an open position in which said catch channel is oriented normal to and extends beyond the edge of the second portion of the container, said catch channel in said open position of said knob being enterable by said catch when the first and second portions of the container are pivoted into the closed position thereof;
• said recess and said catch channel having sidewalls so configured that rotation of said knob into a position out of said open position when said first and second portions are in the closed position captures said catch in said recess and of said catch channel to preventing pivoting of the first and second portions out of the closed position thereof.