| 摘要 |
A method of winding a length of plastic ribbon (such as a zipper of the type used in reclosable packaging) around a cylinder of a spool having a first flange at one end and a second flange at the other end, comprising the following steps: (a) winding the ribbon with a winding tension in a first range when the portion of the ribbon being wound is within a first volume surrounding a central region of the cylinder; and (b) winding the ribbon with a winding tension in a second range when the portion of the ribbon being wound is within second and third volumes surrounding respective portions of the cylinder disposed between the central region and the first and second flanges respectively. To reduce camber in the portions of the wound ribbon disposed in the second and third volumes, i.e., near the respective spool flanges, the upper limit of the second range of winding tension is less than the lower limit of the first range of winding tension, i.e., the winding tension near the spool flanges is less than the winding tension in the central region.
|
