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A sheet metal pull tab for easy opening cans of the full panel pull-out type which has a special and coordinated configuration, shape and contour of pull-ring, keyhole-shaped slot, nose and nose-forming walls which serve readily without tab failure to rupture the score line formed in a can end for r

A sheet metal pull tab for easy opening cans of the full panel pull-out type which has a special and coordinated configuration, shape and contour of pull-ring, keyhole-shaped slot, nose and nose-forming walls which serve readily without tab failure to rupture the score line formed in a can end for removal of an end panel defined by the score line. The new pull tab structure imparts unusual overall strength to the pull tab that enables the pull tab either to provide greater strength when formed from the same gauge sheet metal or to provide the same strength when formed from lighter gauge sheet metal as compared with similar prior sheet metal pull tabs having the same outer contour; and also to provide such a pull tab structure which reduces the amount of metal, disregarding gauge, that is required to form the strong pull tab structure.

대표청구항 ▼

A sheet metal pull tab for a full panel pull-out easy opening metal can including, flat top and rounded outer side walls forming a tab perimetric contour defined by spaced curved tab ring and nose ends connected by parallel tab sides; the flat tab top wall having an inner side wall defining a keyhol

A sheet metal pull tab for a full panel pull-out easy opening metal can including, flat top and rounded outer side walls forming a tab perimetric contour defined by spaced curved tab ring and nose ends connected by parallel tab sides; the flat tab top wall having an inner side wall defining a keyhole-shaped slot; the contour of the keyhole slot including a curved ring portion at the curved tab ring end connected by reversely curved portions to parallel portions extending toward the tab nose end; the rounded outer tab side wall having an inturned bead-forming flange extending around the tab perimeter ring end, parallel sides, and portions of the curved nose end, and ending in spaced bead terminals; the curved tab ring portion inner side wall being rounded and having an inturned bead-forming flange at the ring end, said last-mentioned bead-forming flange terminating at the reversely curved portion connections with said parallel keyhole portions; the inner keyhole slot side wall parallel portions being connected adjacent the tab nose end by portions curved inwardly toward the nose end; said last-mentioned inward curved inner side wall portions being connected with straight wall portions angled at 90° toward each other; the angled straight wall portions at the tab nose end extending downward from the flat tab top wall to and being connected with a generally right triangularly-shaped flat nose bottom wall; the parallel, inwardly curved, and straight angled tab inner side wall portions extending vertically downward from the flat tab top wall and vertically with respect to said flat nose bottom wall; the flat tab top wall at the tab nose end and the 90°angled straight tab inner side wall portions merging in a generally rectangular flat nose tip offset upward from the nose bottom wall in the zone of the projected intersection of the angled straight vertically oriented tab inner side wall portions; an ear extending rearward from the nose bottom wall; there being rivet-receiving aperture means formed in the ear; a narrow tapered side extension of the nose bottom wall located at either side of and spaced from the ear projecting toward the ear from the lower ends of the parallel keyhole vertical side wall portions; the narrow tapered side extensions terminating rearward of the nose bottom wall where tHe reversely curved inner side wall portions merge with the keyhole parallel inner side wall portions; there being curved slots formed between the ear and tapered side extensions; the curved slots having terminal zones located at hypotenuse corners of the right triangular nose bottom wall; the nose bottom wall right-angled corner being located adjacent the rectangular nose tip; the flat tab top wall having maximum width between adjacent parallel outer side and inner keyhole walls laterally of a tab centerline passing through the nose tip and rivet-receiving aperture means; and the flat tab top wall having a nose portion between each bead terminal and a straight angled nose wall portion whose width is approximately ½the maximum top wall width measured on a line extending radially of the center of the rivet-receiving aperture means.