Automatic control of short term sliver irregularities by the detection of drafting force.

A new instrument that measures drafting force continuously and eliminates short term variations in sliver weight has been developed by the authors (Figs. 1, 2). The electronic instrument consists of magnetic power amplifiers (Fig. 3) with a loop transfer function H (S) as given by eq. (6). The instrument has been found to successfully reduce short term sliver weight irregularities. The effect of loop gain and time constant on sliver irregularity has also been investigated. Also by changing the corner frequency ωa of the instrument, the effect of ωa on the wave length of sliver irregularities has been obtained (see Fig. 18).