GB793044A - Improvements in or relating to the production of bulky yarn - Google Patents

Abstract

793,044. Spinning and finishing yarns; thread guides; roller arrangements in textile spinning &c. machines. BRITISH CELANESE, Ltd. Oct. 18, 1955 [Oct. 20, 1954], No. 30213/54. Classes 120(2) and 120(3) An apparatus for producing bulky (and looped) yarn from a continuous filament yarn, as by the process of Specification 790,911, comprises an inlet tube extending through a chamber and provided with a jet tip which faces and enters the mouth of a venturi passage i.e. a passage beginning as a cone with a vertical angle of less than 60 degrees, converging steadily to a throat and then slowly enlarging, and co-operating therewith to form an annular passage for a fluid stream blown under pressure into the chamber and out through the venturi passage. The unit 7, Figs. 1 and 2, comprises a tube 8 having an enlarged yarn entrance 13 and threaded at 14 and 15 to be engaged by a spring-loaded head 17 and a collar 21 and jet tip 9, the tube slidably entering a tubular body 10, which is embraced by a union 11 for connecting to a compressed air line, and carries an extractor end piece 12 in which is formed a passage having a conical entrance 35 leading to a throat 36 and reopening to an oulet 37 and which co-operates with two conical portions on the tip viz. 38 and 41, to form an annular passage with a throat 42. The number of loops and curls in the bulked yarn may be increased by use of a cap 56, Fig. 5, which is removably attached to the extractor 12 by bayonet-fitting pins 57 and slots 58 and has an outlet 59 which is of smaller diameter than, and offset relatively to the axis of, the outlet 37. In the application shown in Fig. 3, untwisted yarn 43 is passed around a large diameter portion 44 of roller (being held in contact therewith by a loaded roller 47), upwardly through the jet unit 7, is drawn back to the nip between a small diameter portion 45 of the roller and a cork roller 46, passes through a guide 48, and is taken up on a ring spindle 49; the difference in diameter of the portions 44 and 45 compensates for the contraction of the yarn the loops in which are secured by the inserted twist. As shown in Fig. 4, a twisted or untwisted yarn 51, drawn from, or drawn from and twisted by, a stationary or rotating package 52, is forwarded by feed rollers 53 and passed through the jet unit 7 and a tension device 54 and is taken up on a drumdriven winding spindle 55 which operates at such speed in relation to the speed of rollers 53 as to allow for yarn contraction. Reference has been directed by the Comptroller to Specification 732,929.