| 摘要 |
<p>PURPOSE:To form a box having a good welded condition free from water-leakage even through a thin resin sheet and to enable the formation of a tray-shaped box whose side wall is inclined outwards, too, by arranging a bottom-surface plate which will come to the position of the concave bottom surface of a lower die frame when it is pushed downwards by a press board. CONSTITUTION:A bottom-surface plate 5 is ordinarily located at a position forming a continuous plane in company with the upper surface of a lower die frame 4. When the bottom-surface plate 4 is pushed through an interposed resin sheet A, cut into the unfolded shape of a box, by a press board 3, the bottom-surface plate 5 is lowered to a position forming the bottom surface of a concavity 4'. The parts of the resin sheet A coresponding to the corners between the side walls of the box are hot-melted by heating blocks 2, and the resin sheet A is inserted into the lower die frame 4 so that the end surfaces corresponding to the corners between the side walls of the box are welded.</p> |
