| 摘要 |
In order to make a sack with a fold edge and a pleat made in the short time, rigid materials can be adopted. At the corresponding position away from position needing the pleat height (10) at the position of the opening of the sack material (12), the fold edge (1) of the sack material (6) adopts the guide edges positioned on both sides of the sack material to position and clamp two outfolding edges (4), (5); the clamping depth is always equal to the folding depth (11) of the fold edge; two outfolding edges are turned about 90 DEG to a flat surface perpendicular to the surface of the sack material every time, and infolding edges (3) are expanded to a trapezoid; after the fold surface of the trapezoid is folded along the expanded infolding edges, a pleating plate (21) which is folded is pushed between the mutually relative side walls (16), (17), and is connected with an open-mouth sack edge (15) on the longitudinal direction of the sack material in a pleating area. |
