摘要 |
A method and apparatus for deep drawing a product from a blank ( 5 ), in which, during deep drawing, the blank ( 5 ) is held near its edge by a downholder ( 8 ) against a die ring cooperating with the downholder ( 8 ), thereby preventing, at least reducing wrinkle formation in the blank, by adjusting, at the beginning of deep drawing, the downholder ( 8 ) such that a downholder ( 8 ) force exerted by the downholder ( 8 ) on the edge of the blank is relatively small, and by controlling, during the further course of the process, the downholder ( 8 ) on the basis of a predetermined thickness trend of the mentioned edge during deep drawing and/or a trend or critical value derived from this thickness trend.
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