| 摘要 |
A method of cold drawing, forming and otherwise cold working a sheet metal blank to form a can end member for seaming to one end of a can body in which the can end has a continuous score line along which the can end is severed for complete removal of an end panel, and in which a protective metal fold is formed in the can end with portions of the fold metal extending to a location circumferentially outward beneath and beyond the score line location to present a dull hazard-free edge on the end panel when torn from the can end member. The metal working procedure includes steps of blanking, drawing, panel forming, curling, redrawing, resizing, coining, scoring, out-folding and embossing, by cold working operations performed on a thin sheet metal blank to produce a can end, accompanied by forming an integral rivet to join a pull tab to the end panel portion of the can end. A can end with a continuous annular three layer fold having a continuous annular score line in the top layer. The two lower layers extend radially beneath and beyond the location of the score line. There is a 100 DEG sector of the three layer fold part extending on either side of a center line of a pull tab connected to the can end used to sever the score line which is thicker than the remaining extent of the continuous fold; and the top layer in the sector has a clearance space above the two lower layers.
|
