GB1082224A - A method of and an apparatus for transporting filaments - Google Patents

Abstract

1,082,224. Spinning apparatus. IMPERIAL CHEMICAL INDUSTRIES Ltd. Feb. 7, 1966 [Feb. 25, 1965], No. 8164/65. Heading B5B. A method of transporting filaments from a spinneret comprises passing the filaments from the spinneret directly into a zone of controlled pressure in which a gas is fed under pressure in such a manner that there is no gas flow past the spinneret in the direction of travel of the filaments and from which zone the gas is allowed to escape in such a manner that it entrains the filaments and carries them from the zone in a substantially separated condition. Preferably, the gas flowing through and from the outlet of the zone exerts a tension on the filaments entrained thereby and attenuates and molecularly orientates these filaments. Such filaments may be collected in the form of a non-woven batt. Apparatus for transporting filaments from a spinneret comprises a hollow body mounted immediately below and surrounding the face of the spinneret and making a gas tight seal therewith, inlet means mounted in the body below the spinneret and adapted to feed a gas under pressure into the body, and restrioted outlet means in the body through which, in operation, the gas is allowed to escape in such a manner that it entrains the filaments and carries them from the body in a substantially separate condition. Two forms of suitable apparatus are shown in Figs. 1 and 3. In use, the apparatus of Fig. 1 is threaded up and cylinder 10 is first bolted to pack body 16 and filaments 60 (only one of which is shown in 2) are led away by means of a suction gun. Female member 26 is then temporarily supported beneath cylinder 10 and filaments 60 are passed through the arcuate slot 40 (Fig. 2). Female member 26 is then mounted on the cylinder 10. The male assembly is then secured to the female member 26 and the filaments pass from the interior of the cylinder 10 to the exterior via restricted outlet formed by the slot 54. Compressed air is then introduced through inlet tube 57 into cylinder 10 and the suction gun removed. The compressed air, which is at substantially constant pressure throughout cylinder 10, escapes through outlet 54 and in so doing entrains filaments 60 and carries them through outlet 54 from which they emerge well separated. Such filaments may be laid down on receiving surfaces of " Duralumin " (Registered Trade Mark) or copper mesh to form batts. Such batts are not affected by electrostatic disruption, are coherent and do not disintegrate on handling. Filaments transported by the apparatus may emerge as continuous or discontinuous filaments depending upon the operating conditions. Fig. 3 illustrates an alternative form of apparatus differing from that of Figs. 1 and 2 in the construction of the male and female members. The male and female members define a restricted outlet 76 in the form of an annular slot. The birefring- ence and denier per filament of filaments transported by the apparatus can be altered by adjusting factors such as, throughput, spinning temperature, threadline temperature, compressed air supply, preheating of air, use of steam, cylinder dimensions, and outlet slot dimensions, e.g. width, depth and aerodynamic shape. An outlet slot of non-uniform dimensions along its length can be designed to produce filaments of mixed birefringence, suitable in the products of batts of mixed drawn and undrawn filaments. In Figs. 1 and 3 annular outlet slots are used (see slots 38 and 40, Fig. 2), but straight outlet slots may be used in conjunction with curtain spinnerets. The position below the spinneret of the gas inlet to the cylinder shown at 57 may be altered when more than one inlet is used in order to give a more uniform distribution of gas within the cylinder. The distribution of gas passing through the outlet slot may also be modified by arranging deflector plates beneath the outlet slot or by directing additional gas streams across the outlet slot or along the path of travel of the filaments.. Additional gas streams may be utilized to traverse the filaments. The apparatus and method of the invention are suitable for the preparation of yarns and non-woven materials made from polyamides, polyolefins and polyesters. In an example, the spinning of polyethylene terephthalate filaments is described. When used in the preparation of non- woven materials the..method provides a single stage method of laying filamentary batts.