| 摘要 |
PURPOSE:To produce the hard vinyl chloride sheet with reliable bending strength and accurate profile of bent fillet by a method wherein a concave fold is formed by means of depressing a mold on a fold position of hard vinyl chloride sheet and high-frequency heating and melting the fold position and leaving the both end fold parts. CONSTITUTION:Side sheets 1, 2, 3, 4, connecting piece 5, end side sheets 6, 7, hanging piece 8 and folding pieces 9 made of a hard vinyl chloride sheet are continuously connected to one another through the intermediary of respective fold (a). The folds (a) are formed by means of depressing a round edge mold (c) on the fold forming positions of hard vinyl chloride sheet and high-frequency heating and melting said positions. The folds (a) are not only depressed by the mold (c) but also high-frequency heated while they are being depressed to make the folds thinner also growing both sides of the folds into padding due to a bit of material moving to both sides. Through these procedures, the bending strength may be improved making a cartoning machine applicable to this sheet. |
