Patent GB-1268985-A (GB)
Title: Method of air-conditioning undrawn yarn packages in a drawing machine
IPC: B65H54/70
Filed: 1970-05-22
Abstract: 1,268,985. Air-conditioning undrawn yarn packages in a drawing machine. TEIJIN Ltd. 22 May, 1970 [26 May, 1969], No. 25038/70. Heading B5B. In a process for unwinding undrawn synthetic yarns from packages supported on a creel stand located above a hot drawing machine, feeding the unwound yarn to the hot drawing zone in which the yarn is drawn and from which the yarn is withdrawn and wound up, air which has been conditioned to a predetermined temperature and humidity is blown against and over the packages of undrawn yarn from above or behind the packages and sucking the current of air rising from the hot drawing zone and the current of conditional air away from the yarn packages into a discharge duct to thereby prevent the current of hot air from rising from the hot drawing zone into the region of the packages of undrawn yarn. As shown in Fig. 1, an apparatus for carrying out the process of the invention comprises a creel stand 1 located above a hot drawing machine 10 to serve as a support for the undrawn yarn supply bobbins. The creel stand is provided with an air chamber 6 comprising a base 1<SP>1</SP>, pervious front and rear walls 7 and imperforate side-walls (not shown). The walls 7 may be perforated plates, wire gauze or sintered metal plates. On each wall 7 are mounted bobbin holders 2 on which are placed supply bobbins 3 of undrawn yarn Y wound as packages. Air duct 4 disposed above air chamber 6 communicates with the chamber through the inlet duct 5. Guide brackets 8 are mounted on the frame of creel stand 1 and yarn guides 9 are mounted on the brackets 8 coaxially with the bobbins 3 and spaced from the free ends of the bobbins. Below guides 9 are disposed hot drawing, twisting and winding devices of conventional type. Undrawn yarn Y is unwound from the supply bobbins 3 and pulled downwards through the guides 9 and guide 101 by the driven feed roll 103 with its associated rotatable press roll 104 mounted in the pivoted arm 102. The yarn is drawn by the draw roll 107 with its associated separator roll 108 over and in contact with the curved plate 106 which is heated by the electric heater 105. The draw roll 107 is driven at a higher peripheral speed than the feed roll 103, whereby the yarn is hot drawn at a predetermined draw ratio. The drawn yarn Y<SP>1</SP> is withdrawn from the draw roll 107 through the balloon guide 109 by the ring and traveller assembly 110 and twisted and wound on wind-up bobbin 111 as a package. Pressurized air conditioned to a predetermined humidity and temperature supplied from the duct 4 is fed into air chamber 6 via the duct 5 and blown through the pervious wall 7 (as shown by the plain line arrows a) to envelop the yarn packages 3 with a stream of conditioned air and prevent the streams of heated air rising from the heated plate 106 from approaching the vicinity of the packages of undrawn yarn 3. The conditioned air which has been blown over the packages 3 is preferably drawn downwards along the periphery of the drawing machine 10 by the suction of the suction duct 21 which communicates with an exhaust fan. The stream of air heated by the hot-plate 106 is also drawn downwards by the suction duct 21 (as shown by the wavy line arrows b) and passes around the wind-up mechanism 110, whereby yarn breakage due to friction between the drawn yarn and the traveller of the wind-up mechanism are prevented. In a second embodiment (Fig. 2, not shown), the conditioned air is blown downwards on to the packages of undrawn yarn from ducts located above the packages. In a third embodiment (Fig. 3, not shown) of the apparatus both the conditioned air which has been blown over the packages of undrawn yarn and the heated air rising from the hot drawing zone are withdrawn from the zone containing the packages and from the hot drawing zone by a suction duct spaced some distance from the front of the creel stand and at about the level of the top of the stand. Examples relate to polyethylene terephthalate yarn, but the apparatus is stated to be especially useful with polyamide and polyester yarns.