GB815647A - Improvements relating to the crimping of yarns - Google Patents

Abstract

815,647. Crimping yarns and fibres. BRITISH CELANESE Ltd. Aug. 24, 1956 [Aug. 26, 1955], No. 24578/55. Class 120(3) Multifilamentary or staple fibre yarns (or bundles of filaments) e.g. yarns of organic derivatives of cellulose such as cellulose acetate, regenerated cellulose such as viscose, polyamides such as polyhexamethylene adipamide, polyamino acids such as polyaminocaproic acid, or a polyester such as polyethylene terephthalate are crimped by running at least one yarn together with a wire between a doubling point for the yarn and wire and a separating point therefor, between which points the yarn and wire are twisted together with a number of turns of doubling twist (which is algebraically non-zero) and setting in the yarn, in a setting zone between the points, the twist imposed on the fibres thereof by local doubling twist in the zone. The wire e.g. a fine metal wire in the form of an endless loop or continuous length, need not become deformed and may be returned to the doubling point or rewound for repeated use. Setting may be effected by dry heat e.g. by passing the yarn through an electrically heated tube or in contact with a heated surface such as a curved plate or channel, or a fluid e.g. steam, hot air, solvent vapours, hot water, and, optionally, with direct heating of the wire. The yarns may be doubled with similar or different, crimped or uncrimped yarns and/or of opposed twists. In the process represented in Fig. 1, yarn 3 and wire 6 drawn from packages 4 and 7 pass through a guide 5 and a tensioner 8, one on each side of a waisted roller 9, through a heated setting tube 12, one on each side of a waisted roller 13, and are wound on bobbins 14 and 15: in threading-up, the yarn and wire 16 between the rollers 9 and 13 are twisted together e.g. 1,000 turns, as by means of a portable electric motor (not shown). In another process, Fig. 2, a yarn 21 drawn from a package 22 passes through a tensioner 23 to a guide 24 where it is joined by a wire 25 formed as an endless loop supported on guides 30 and continuously advanced by nip rollers 29; the yarn or wire together are tensioned by a braked pulley 26, pass one each side of the roller 9, thence, in the intertwisted form 20, through the tube 12, one on each side of the roller 13, and the yarn passes through nip rollers 27 (rotating at the same peripheral speed as roller 29) to a take-up device 28 (which may rotate at a peripheral speed less than that of the rollers 27 and 29) while the wire passes to its return run 33. The wire, within the setting zone, is heated by passage of electric current therethrough between contacts 31 and 32. Specifications 424,880, 458,595, 471,061 and 790,128 are referred to.