GB827561A - Improvements in elastic yarns and in method and apparatus for producing same - Google Patents

Abstract

827,561. Spinning yarn; roller arrangements in textile spinning &c. machines. UNITED STATES RUBBER CO. Aug. 19, 1957 [March 13, 1957], No. 26059/57. Classes 120(2) and 120(3) [Also in Group XXV] A balanced, single cover, elastic yarn having an elongation of at least 100% comprises a twisted or untwisted elastic e.g. rubber, core and a fibrous covering yarn or roving wrapped thereabout, the ratio of the elongated length of core at break in a given length of covered relaxed yarn divided by the length of fibrous cover in the given length being less than 1.50. Yarn is produced by twisting an elastic core thread sufficiently to balance the torque of the intended cover, stretching, and helically wrapping the roving &c. thereon. In a spinning process shown in Fig. 2, rubber thread R is fed from a spool 15 to rolls 50, 18, and its stretch regulated by the control of a roll 17: roving 27 fed from packages 20, 21, is drafted by passage through rollers 23, 24; 25, 26; and 50, 18. As the roving emerges from rollers 50, 18 with thread R it is wrapped therearound in a direction opposed to the twist therein as the composite yarn passes through a ring-traveller 28 and is wound on a rotating bobbin 30. In a twisting method shown in Fig. 3, the thread R, withdrawn from spool 15<SP>1</SP> and stretched under control of roll 17<SP>1</SP>, is merged with yarns Y at nip rolls 31, 32 and covered thereby as the composite yarn is passed through ring- traveller 38 and wound on a rotating bobbin 40. As shown in Figs. 4 or 5, rolls 50, 18, and 31, 32, comprise resilient cots 43, 43<SP>1</SP> or 43<SP>11</SP> for gripping the covering roving &c. 51 and a grooved pulley 44 or disc 45 enabling the thread R to pass through the rollers without being gripped in the nip.