Metallic container closure having internal pressure release function

Abstract

A metallic container closure of the invention comprises a shell of a thin metal sheet having a circular top panel wall (7) and a skirt wall (9) , and a synthetic resin liner arranged in the shell, the skirt wall (9) having a thread-forming region and an annular groove (17) positioned at an upper end portion of the thread-forming region, wherein an internal pressure release line A extending in thecircumferential direction is arranged in the skirt wall (9) at a portion over the annular groove (17), and annular bead (30) is arranged so as to pass through between the internal pressure release line (A) and the annular groove (17). The metallic container closure effectively releases the gas when the pressure in the container is elevated and effectively prevents the skirt wall from being deformed at a portion where the internal pressure release line (A) is formed when it is being wrap-seamed with the mouth-and-neck portion of the container.

Description

technical field [0001] The present invention relates to a metal container cap having an internal pressure releasing characteristic, that is, a characteristic of automatically releasing the internal pressure of the container when the internal pressure of the container rises excessively. Background technique [0002] Generally, after filling carbonated beverages, etc. into the container, a container cap is attached to the mouth and neck of the container to seal the mouth and neck, and when the contents of the container are overheated, the internal pressure of the container phenomenon of excessive rise. In addition, when the container cap is detached from the mouth and neck of the container, and then the container cap is attached to the container mouth and neck again to seal the container, the internal pressure of the container may rise excessively when the contents rot and ferment. [0003] When the internal pressure of the container increases as described above, the cap of t...

AI Technical Summary

Problems solved by technology

However, in metal sheets made of high tensile strength, for example, the tensile strength is 200 to 230N / mm 2 When a thin plate made of aluminum base alloy (Aluminum Base Alloys) forms a thin shell, the drop impact resistance is improved, and the breakage of the bridging portion between the gaps caused by the drop impact can be effectively prevented, but on the contrary, due to the rise of the internal pressure, the gap The bridging part is not broken, and the internal pressure is not released, so the internal pressure of the container may rise excessively, and the top wall of the container cap may fly out or the container may be damaged.