| 摘要 |
Method and apparatus for forming a series of elongated troughs having different widths at their opposite ends into a metal foil strip in several forming stages with the aid of sets of upper and lower dies which, one after the other, engage the metal strip which is promoted stepwise from stage to stage. The troughs are formed in a pre-forming stage with the same width at both ends and in the final forming stages the width of the trough at one end is reduced by the formation of pleats so as to obtain the final form of the troughs without bending of the strip.
|
