Abstract: The invention is directed to a metallic easy-opening can end, and to a method of manufacturing the same, the can end having a tear panel which is highly resistant to blowout pressure. The can end is first drawn between a preforming punch and a die to an outwardly open concave configuration, and is thereafter compression scored between a scoring punch and a scoring anvil to reduce the thickness of the drawn metal, thus forming the removable tear panel.

Abstract: The invention is directed to a metallic easy-opening can end, and to a method of manufacturing the same, the can end having a tear panel which is highly resistant to blowout pressure. The can end is first drawn between a preforming punch and a die to an outwardly open concave configuration, and is thereafter compression scored between a scoring punch and a scoring anvil to reduce the thickness of the drawn metal, thus forming the removable tear panel.

Abstract: An improved tooling configuration enables production of an end panel opening score line without loss of the enamel protective coating on the reverse side of the end panel. Current scoring methods frequently result in enamel loss, and hence, necessitate coating repair before the end panel may be attached to the can body. By controlling the angular relationship of the score punch and anvil, while simultaneously confining the displaced metal, the enamel which was previously applied to the panel is retained substantially in place with only a slight reduction in thickness. Punch angles of 90.degree. - 100.degree. and anvil angles of 25.degree. - 35.degree. have been found to be effective, with a punch angle of 90.degree. and an anvil angle of 30.degree. being optimum. The metal may best be confined and controlled by the simultaneous formation of an anti-fracture score concentric with, and radially inward of the opening score line.

Abstract: An improved easy-open end closure which maintains close contact between a tab and container end panel prior to opening, regardless of doming of the end panel. An integral rivet is formed on the end panel inclined off-center 10.degree.-20.degree. toward the end panel center, the rivet securing the pull tab thereto whereby the tab converges with the end panel toward the periphery thereof.SUMMARY OF THE INVENTIONWhen easy-open containers employing integral off-center rivets are subjected to excessive internal pressure the end closure bulges outwardly and exerts an upward force on the tab. Occassionally the tab is rotated upwardly about the rivet and retains this displacement after the internal pressure has been reduced and the end panel bulging has subsided. Tab displacement of this sort detracts from the appearance of the container.

Abstract: An improved non-detachable end closure has an outwardly facing dome-shaped opening flap. Non-detachable end closures, wherein the rivet for tab attachment is located in the center of the opening flap, may evidence low panel distortion under internal pressure. Forming the opening flap as an outwardly-facing dome provides increased distortion resistance and making the tab ring-shaped permits nesting of the ring in shielded location to prevent accidental opening. The arrangement of a dome within a well, which nests the ring tab, permits locating an expandable securing lug for the tab to the non-detachable dome panel within an upwardly widening space between the dome and interior of the ring tab. The structure makes the ring tab relatively inaccessible and inhibits the tendency of users who are familiar with current detachable ring pull tabs from pulling the tab off and encourages the user to push the tab inwardly.