抄録
An attempt has been made to measure the bulkiness of slivers and of yarns with the frictor designed by the authors initially for the purpose of detecting sliver thickness irregularity. Results:
1) When a sliver is inserted into the frictor with its ends tied together to form a sliver loop and circulated repeatedly, the dynamic drawing force of the sliver against the frictor decreases with each repetition (Figs. 1 and 2). We call the curve showing the drawing force against the number of repetitions “the bulkiness curve of sliver.” A similar result is obtained by inserting yarn bundles into the frictor and shifting them back and forth.
2) A method of testing and evaluating sliver properties with the aid of the frictor has been established.
3) The factors affecting the bulkiness of slivers and of yarn bundles have been investigated in terms of fiber orientation, fiber length, fineness and yarn count, twist multiplier, etc.
4) The bulkiness of synthetic fibers, natural fibers and their blends have been compared in terms of the behavior of sliver and yarn bunldes when they are passed through the frictor.
