Silver weight unevenness correcting apparatus

摘要

Sliver weight unevenness correcting apparatus of a feed-forward type has: a sliver weight measuring section for detecting the variations in weight of a bundle of slivers; a correcting draft device having front rollers disposed downstream of the sliver weight measuring section relative to the direction of advancement of slivers, the front rollers being rotated at a constant speed, and back rollers disposed between the sliver weight measuring section and the front rollers, the back rollers being rotated at a variable speed; a rotation detector for detecting the number of revolutions of the front rollers; an unevenness correcting circuit having a ratio circuit for operating a ratio (E0/E1) between a reference sliver weight (E0) and the detected weight (E1) thereof, a delay circuit for delaying the speed control of the back rollers of the correcting draft device for a predetermined period of time, and a contrasting operational circuit for multiplying the ratio (E0/E1) and a ratio (NF/k) between the number (NF) of revolutions of the front rollers and a reference draft value (k) and for producing a multiplied signal (E0/E1x NF/k); and a speed control circuit for producing a speed control signal responsive to the multiplied signal to control the speed of back rollers through a rotation transmitting mechanism. This arrangement enables accurate correction of sliver weight unevenness even short in wavelength in a drawing frame running at a high speed.