摘要 |
A package of tape is formed with flanged portions built up at the ends and a central helical traverse portion. The flanged portions are effectively formed by a plurality of separate spiral windings each of which is interlocked with each other and the central traverse portion. The central portion is formed from a plurality of helical traverses with reversal positions slightly inside the inner edge of the flanged portions. Either the central traverse portion or the flanged portions is built up first to form a step following which the other is built up to meet the step. The step cannot be so high that the tape cannot traverse the step. The extreme ends of the package is thus formed by the stable spiral windings while edge drop-off from the ends of the traverse portion is limited to height of the last helical traverse. |