| 摘要 |
The method herein disclosed is to groove the straw circumferentially, one groove at a time, progressively part way toward one end of the straw, starting inwardly from the other end, the grooves having sides of unequal length for snapping over center in flexing or straightening the straw. The machine involves one drum on which the grooving is performed, and a second drum on which the grooved straws are subjected to endwise compression to close the corrugations in the grooved portion and define reentrant folds.
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