| 摘要 |
A method of eliminating corrugation in central umbrella cover, being made of a plain weave cloth, in which the weft has no stretchability, while the warp has a slight stretchability; before the umbrella cloth being cut into an umbrella cover, the umbrella cover and the main rib are set a different angle of ten degrees; the tail end of the main ribs and the sewing points of the umbrella cloth are not fallen on the parallel line of the warp or the weft; from the sewing points to the central part of the ribs, there are different length so as to balance the tension of various stretch points; the edge of the umbrella cover is cut out and sewed properly so as to provide suitable corrugation-proof. When the umbrella is opened, the central portion of the umbrella cover would not have corrugation and looseness because of the main ribs having a slight curvature, and the oblique weave mesh able to balance the stretched tension.
|
