Slubbed open end spun yarn and process and device for producing it

摘要

A method of making slub or thick and thin yarns with twist variation an open end spinning machines operates by changing the speed of the yarn as it leaves the rotor of the .open end spinning machine. The method produces a unique slub yarn which has a portion of high twist adjacent the slub -in the yarn which has lower yarn twist. In the apparatus, the roving 12 is spun by a rotor in a housing 14 and leaves through a doff tube 18 from whence it passes through rollers 21,23 to be wound on to a roll 28. A lever 20 with a roller 19 at its end swings randomly up and down to lengthen and shorten the yarn between the doff tube 18 and rollers 21,23 thereby speeding up and slowing down the speed of the yarn leaving the doff tube.