| 摘要 |
PROBLEM TO BE SOLVED: To produce a cup bottom having only folds which are not so high to lie on top of one another when the fringe of a bottom part is compressed by a method in which after raw paper being stretched, mold clamping force is reduced gradually, a peripheral part enters an opening part, and it is bent substantially at right angle with regard to a middle part. SOLUTION: The central part of raw paper which is not tightened is stretched radially. After the paper being stretched slightly, a rapping part 80A is started to be drawn, mold clamping force is reduced gradually, and a outer barrel part can be drawn into an opening part 88A. The paper is contracted at a speed not to be broken. A radial clearance between the outside cylindrical surface of a draw-out part 82A and the cylindrical surface of the opening part 88A is somewhat narrower than the paper passing through the clearance so that the paper is compressed. In this way, a peripheral part is bent at right angle with regard to the central part of the paper and also compressed. |
