16—HIGH-SPEED PHOTOGRAPHIC STUDIES OF THE FIBRE CONFIGURATION DURING TRANSFER FROM THE OPENING ROLLER OF A ROTOR-SPINNING UNIT

Abstract

A study is reported of the configurations fibres adopt in open-end spinning during their transfer from the opening roller down the transfer channel to the rotor. A technique was developed for quantifying the fibre configurations in three-dimensional (3-D) space. This involved taking high-speed (3-μs flash) photographs of the configurations, viewed from two vertical planes placed mutually at right angles. The photographic images were then digitized and fed into a micro-computer, and numerical values relating to the fibre configurations were calculated. The relationship between the numerical data and the changes in the ratio of the air-flow speed at the inlet of the transfer channel to the peripheral speed of the opening roller was examined. The results obtained showed that, as this ratio increased, the percentage of fibres with a near-straight configuration also increased. Increasing the ratio to the maximum for the machine design increased the number of near-straight fibres to only 28% of the total number of observed configurations. The statistics used to quantify the observed fibre shapes showed good correlation with the classification of the fibre configurations. It may therefore be possible to use these statistics for optimizing the design of the fibre-transfer channel.