Patent GB-892587-A (GB)
Title: Improvements in or relating to the treatment of yarn
Inventor: BREEN ALVIN LEONARD
IPC: D02G1/16
Filed: 1958-11-27
Abstract: 892,587. Spinning and finishing yarns; twist tubes. DU PONT DE NEMOURS & CO., E.I. Nov. 27, 1958, No. 38367/58. Class 120(3) Staple yarn having a multitude of irunodal loops and protruding fibre ends irregularly spaced along its surface is formed by feeding staple fibre yarn through a high velocity gas jet, e.g. the apparatus described in Specifications 732,929 and 871,112, and controlling the separation of the fibres from each other so that it is effective over a distance less than the average length of the fibre. Two or more staple yarns or one or more continuous filament yarns with one or more staple yarns, as single ends or doubled with doubling twist opposing the twists in the individual yarns, may be fed together to the jet and subsequently separated or retained as composite blended, cored or intertwisted yarns. Fibre ends and convolutions are secured by residual or applied twist. The constituent yarns may comprise fibres of regenerated (viscose) cellulose, cellulose acetate, nylon, polyacrylonitrile, polyethylene terephthalate and/or cotton which may be crimped. During treatment in the jet, the yarn may be untwisted by the falsetwisting action of the jet, the run of the twist being arrested by snubbing the yarn on each side of the jet and so that the distance between snubbing points is less than the average length of the staple fibres. Entrance and exit surfaces of the jet may effect the snubbing. The twist and/or doubling twist in the yarns may be sufficient to control the fibre separation. Yarn emerging from the jet may be snubbed and removed from the gas stream by impinging against a baffle plate, and may then pass in contact with loose fibres, e.g. in the form of flock, which are entrained therein. The gas may be air, carbon dioxide, steam or yarn-setting vapours. As shown in Fig. 1, yarn 10 is fed by driven feed rollers 12 and 14 through a guide 18 to a jet nozzle comprising a hollow member 28 which terminates as a cone 32 within a hollow body 24 to which compressed air is supplied through a pipe 22 under regulation of a valve 34. Yarn emerging through exit 26 is diverted by a plate 36, or a guide (not shown) passes through a guide 40, and is taken-up by rollers 44, 46, driven at a peripheral speed less than that of rolls 12, 14, the resultant overfeed controlling the extent of the bulking action. In modified jet nozzles, Figs. 2, 3 and 4 (not shown) the air entrance intercepts the yarn passageway at an angle of about 45 degrees and/or is off-set to create a rotating jet stream and an adjustable hypodermic needle provides a passage for introduction of a selfthreaded yarn into the nozzle. The bulking may be effected by a glass or stainless steel T-tube through the leg of which compressed air is passed to deflect yarn from its vertical path through the other limbs of the T, Fig. 13 (not shown). The untwisting and bulking actions may be effected separately by "torque" and "texturing" jets and the yarn advanced by stepped draw rolls, Figs. 8 arid 9 (not shown). Flock may be added to the bulked yarn in a combined jet and baffled chamber, Fig. 11 (not shown).