Mechanical analysis on constant cross-section segment of fiber band in condensing zone during compact spinning

摘要

It has been found through experiments that under the same spinning condition, the twist of the compact spun yarn is approximately and averagely 5% larger than that of traditional ring-spun yarn. The larger part of the twist is called additional twist. Since the additional twist affects the subsequent processing to some extent, it is worth studying carefully. A theoretical model for analyzing the additional twist of a fiber band with constant cross-section in the condensing zone of a cotton-type compact spinning machine through a mechanical discussion is presented in this paper. Factors affecting the additional twist of the yarn, including the pressure of the profile tube, the friction coefficient between the fiber band and the lattice apron, the length of the suction slot, and the curvature radius of the profile tube, are discussed by numerical integral analysis. The experimental results verified the proposed fiber band additional twist model.