Patent GB-848893-A (GB)
Title: Methods and apparatus for imparting a crimped nature to a yarn
IPC: D02G1/10
Filed: 1957-01-28
Abstract: 848,893. Finishing, tensioning and winding yarn. DEERING MILLIKEN RESEARCH CORPORATION. Jan. 28, 1957 [Jan. 26, 1956], No. 3006/57. Classes 120(2) and 120(3). In a yarn-crimping apparatus, a running, thermoplastic, continuous filament yarn passes into contact with a heated peripheral surface of a driven roll and then, under tension and in an angular path, about the sharp edge of a blade member adjacent to this surface. The roll may constitute one feed roll of a yarn-overfeed system. As shown in Fig. 1, a yarn end from a package 10 is threaded through guides 80, 82, 84, and wrapped several times around the portions 32 and 56 of a driven roll 18 and a free roll 54, thence between a blade 62, detachably secured to an arm 60, and the portion 32 and thereafter to and several turns around the portions 34 and 58 (of the rolls 18 and 54) through a guide 86, optionally to apparatus by which size or an antistatic agent is applied, through a guide 74, finally to take-up apparatus 72. The portion 32, which may be thermally insulated from the portion 34 by means of a gasket therebetween, is heated by an internal annular heater e.g. electrical resistance elements, which maintains constant e.g. by a thermostat, the temperature of the outer surface of the roll 32 and the blade is positioned so that heated yarn passes about the blade edge 64 in a sharply angular manner i.e. it is caused to undergo a change of direction of at least 90 degrees: the blade may be at such an angle to the yarn path that yarn leaving the edge 64 passes in sliding contact with the face of the blade and is cooled thereby. The passage of yarn from large to small diameter portions of rolls 18 and 54 provides an overfeed which allows shrinkage of the yarn, under the influence of heat, under constant tension: if the yarn is incapable of contracting under the influence of heat e.g. it may have been heat-relaxed previously, tension control, other than by overfeeding, is necessary. In the apparatus of Fig. 6, a yarn end 108 is wrapped around an internally heated driven roll 92 and a free roll 104 sufficient turns to prevent slip and withdrawn from roll 92 about a blade edge 125, through a guide 128, around a driven roll 110 interconnected with roll 92 through gears 114, 96, 95, between the latter and a roll 116, around the latter roll, and leaves via a guide 129: tension regulation is provided by driving the roll 110 so that it has a lower peripheral speed than the roll 92 thereby allowing contraction of the yarn under the influence of heat as it leaves the roll 92 and passes about the edge 125: the roll 116 is carried on a pivot arm 118 and urged by a spring 122 into engagement with the roll 110. As shown in Fig. 8, an end of yarn 144 is passed several turns about an internally-heated driven roll 136, having a tapered portion, and a pin 143, withdrawn from the roll and passed about a blade 146 in a sharply angular manner. The yarn is then passed about guides 180 and 182, to winding apparatus 150 comprising a take-up spool 152 driven by peripheral contact with a traverse roll 160, about which the yarn is passed several turns, itself driven through an adjustable constant torque transmitting device 164 comprising gears 168 and 170 coupled through a friction clutch.