Patent GB-905258-A (GB)
Title: Method and apparatus for bulking yarn
IPC: D02G1/00
Filed: 1960-09-15
Abstract: 905,258. Finishing yarns. CHEMSTRAND CORPORATION. Sept. 15, 1960 [Sept. 28, 1959], No. 31756/60. Class 120 (3). Continuous filament, untwisted or twisted yarn is bulked by displacing successive portions of the yarn laterally from the normal path of its travel to form it into a tortuous, e.g. corrugated, shape, the displacement comprising a continuous and progressive varying of the displacement of alternate portions of the yarn from such path to predetermined distance ; transferring the yarn to a storage area wherein the yarn is maintained in its deformed state ; continuously moving the yarn through the area in relaxed condition for a predetermined period of time for treatment, e.g. heating and/or cooling, to cause the yarn to be permanently set and withdrawing the yarn from the area to be collected in orderly manner. The yarn may be preheated and/or continuously attenuated before lateral displacement. Yarn speeds and stretching may be regularly or irregularly varied to produce corresponding effects in the bulked yarn. Yarns having different composition and denier, e.g. one yarn of undrawn thermoplastic filaments and a similar or dissimilar drawn yarn or a yarn which is not thermoplastic, may be combined before bulking. The filaments may be of circular or non-circular, e.g. X- or Y- shaped, cross-section and composed of polyamides, polyesters, polyethylene, polypropylene, polyurethane, copolymers of vinyl acetate and vinyl chloride, vinylidene chloride or acrylonitrile and a minor proportion of mono-olefinic compounds, or acrylonitrile and vinyl chloride, or mixtures thereof, or glass. As shown in Fig. 1, incompletely drawn nylon yarn 10, supplied by a package 11 previously doffed from a spinning-machine (or fed directly therefrom) is passed through a guide 13, feed-rollers 14, around a stretch or draw-pin 15, which may be heated and where most of the stretching is concentrated, two or more turns about separator roll 17 and draw roll 16 rotated at a peripheral speed in excess of that of rolls 14, thence through a guide 18 to the bite formed by pins 20 and 21 carried by rotating hubs 22 and 23, Fig. 2. The overlap of opposed pins progressively diminishes in the direction of movement of the hubs to zero and thereafter the pins become spaced apart, whereby successive portions of the yarn are subjected to lateral displacement alternately in opposite directions. The yarn, guided by a member 26, is transferred to pins 24 carried on an accumulator wheel 25, which is rotated in synchronism with hubs 22, 23, through gears 44, 45, and during its travel thereon the yarn is retained by a wire 30 and may be heated (as by an electric element 27 and reflector shield 28) and/or cooled by passage through the ambient atmosphere. Deformed yarn is doffed from wheel 25 by a guide 31, forwarded by rolls 32, the peripheral speed of which in relation to that of the hubs 22, 23, may be varied, e.g. to determine the extent of relaxation of the yarn on the wheel 25, to a traverse guide 33, and is wound into a package 36. The apparatus of Fig. 4 comprises a preheater 47 and a rotated plate 48 against the periphery of which yarn deformed by pins 20, 21, is pressed by an endless belt 50.