摘要 |
<p>A method of, and apparatus for, forming a tapered-wall metal can body by drawing. The method includes the steps of: (a) producing a metal can body blank (64) comprising a smooth generally cylindrical wall (66), an integral base (68) at one end of said wall, and a trimmed free rim (70) exposed at the opposite, open end of said wall, said rim being generally normal to said wall; (b) advancing the can body blank, base first, into a die (42) (hereafter the "tapered die") by means of a punch (18) engaged inside the blank with only the base of said blank, so as to bring the said wall progressively into greater contact with a tapered internal working surface (44) of the die; (c) simultaneously with the step (b) applying longitudinal pressure, as well as transverse restraint, to the exposed free rim of the said wall by means of a pressure collar (28) whereby to urge the blanks squarely into the tapered die, and maintaining at least that pressure, and restraint, as the blank is advanced progressively further into said tapered die; and (d) continuing the advancement of said blank by continued advancement of said punch and simultaneous application of said longitudinal pressure, and transverse restraint, to said rim, until the said wall lies uniformly against said working surface of said die throughout a desired longitudinal length of said wall.</p> |