Patent GB-1378610-A (GB)
Title: Method of and apparatus for producing yarn-
IPC: D01H4/30
Filed: 1973-08-31
Abstract: 1378610 Open-end spinning INSTITUT TEXTILE DE FRANCE 31 Aug 1973 [1 Sept 1972] 41049/73-Headings D1D and D1F A method of open-end spinning a yarn comprises forming a curtain of fibres into a fringe of individual fibres or groups of fibres mechanically suspended by one of their ends, the free ends of the suspended fibres being progressively and successively supplied to the open end of the yarn being formed in such a manner that a major portion of each fibre is substantially parallel to the yarn being formed in the region of the open end of the yarn, and the end of each fibre being held until the fibre has been integrated into the yarn by the influence of the rotational effect imparted to the yarn by the twisting motion. Apparatus for carrying out the method comprises feed means 1 including a rotary drum 1c, a carding device 2 for receiving a lap of fibres from the feed means 1, the carding device including a carding cylinder 2a rotatable about an axis parallel to the axis of rotation of the drum 1c, a rotatable combing disc 3 for receiving a curtain of carded parallel fibres from the carding cylinder 2a, the combing disc 3 being rotatable about an axis perpendicular to the axis of rotation of the carding cylinder 2a, and the disc 3 being provided on a peripheral surface with a plurality of radially arranged pins 3f cooperating with the pins 2c of the carding cylinder 2a and being inclined relative to the axis of rotation of the disc to extend beyond the periphery of the disc for forming a fringe of fibres mechanically by one end to the said pin, the apparatus also including doffing means 4 for doffing the fibres from the disc 3, and twisting means e.g. false twist tube 5 for twisting fibres doffed from the disc 3 into a yarn 8. The disc 3 is preferably frusto-conical in cross-section, and the doffing means 4 preferably comprises a stationary cam arranged externally of the disc 3 and extending from inwardly below the periphery of the disc to a position adjacent the free ends of the pins 3f. The doffing means may also include an air nozzle directed towards the free ends of the pins or a serrated wheel.  In a further embodiment, a plurality of doffing means are arranged around the circumference of the combing disc 3 for varying the direction of twist produced. Preferably a set of doffing means and twisting means are provided for each direction of twist and the sets are arranged symmetrically relative to the median plane passing through the carding means and the axis of rotation of the combing disc. In a preferred embodiment, the apparatus includes a plurality of spinning heads including feed means, carding means and a combing disc, and a plurality of twisting means, the number of twisting means being greater by one than the number of spinning heads, and the twisting means and the spinning heads being arranged alternately in an array. Common drive means is preferably provided for similar elements of each spinning head. The apparatus preferably also includes means for sucking fibres stuck to the disc and may be operative responsive to a yarn break detector.