11—fibre Motion in Roller and Apron Drafting

The motion of floating fibres in roller and apron drafting has been investigated using an apparatus which permits the direct observation of marked fibres as they pass through the drafting zone at reduced speed. A description of the apparatus is given together with a summary of the results. The experiments show that at some point after being released by the back rollers the fibres are alternately accelerated and decelerated until they finally attain front-roller speed. The point at which this motion commences varies from fibre to fibre, but the average velocity during the ensuing motion is remarkably constant and is practically independent of fibre length, draft and of the type of drafting system. The experiments also confirm that apron drafting gives greater control of the floating fibres than roller drafting.