Methods of and apparatus for crimping,bulking or texturising filaments

摘要

969,648. Finishing yarns. MONSANTO CO. Nov. 24, 1961 [Dec. 12,1960(2)], No. 42168/61. Heading D1F. A thermoplastic filament is crimped or bulked by passing it through a treating zone under tension and uniformly heating one side of the filament to a stress-relief temperature while simultaneously maintaining e.g. by cooling, the opposite side at a lower temperature. Heating may be effected by continuously directing a heated gas e.g. air at a temperature of 60-1100‹F., at successive contiguous points on the filament, or by passing the filament through a non-wetting liquid such as molten solder. The heat-treated filament may be collected under the same tension and thereafter relaxed to develop therein a helex which coils alternately in opposite directions. As shown in Fig. 1, mono- or multifilament yarn 11 is advanced from a bobbin 12, past a tensioning device 14, one turn around a driven "heat-sink" roll 17, thence to a take-up roll 18. A nozzle 21 directs heated air from a source 22 on to the yarn so that the exposed side(s) of the individual filamen (s) is/are heated to or near the softening or melting point of the material thereof: since the yarn is under tension on roll 17 it is flattened and spread so that, in general, the individual filament(s) is/are exposed to the hot air and in contact with roll 17. The main flow of heated air is in a direction parallel to the yarn path, Fig. 3 (not shown). The air temperature, spacing of nozzle from roll, hot air supply temperature, yarn speed, yarn tension and/or roll temperature may be adjusted or controlled to determine and regulate the bulking effects. The roll 17, Fig. 4, is secured to driving shaft 26 and positioned adjacent to a manifold 27 which has air intake and exhaust openings. 28 and 29 and communicating passages 33 and 34 through which a stream of cooling air is directed by fan blades (not shown) integral with the roll. Specification 969, 649 is referred to.