Security device for puncturable cartridge

摘要

A flexible elastic member (41) which may be made from metal or plastic has folds (46,48) which rest on the concave base (7) of the canister. The member is also in contact with a side wall and carries a crown type safety joint (44) at the upper end (42). The safety joint presses against the inner portion of the canister top (11) which is designed to be perforated in use