PRODUCTION OF TEXTURED YARN

Abstract: A method for detecting a yarn break between the cooling drum and the windup in a yarn bulking process and containing the broken end to prevent the broken end from interrupting adjacent threadlines.

Description: TITLE Production of Textured Yarn Bac.kcrro.ind of the Invention This invention relates to the production of multiple ends of textured yarn, and more particularly, it relates to preventing the breakdown of adjacent ends of such yarns up on the occurrence of a breakdown of one such end upstream of the cooling drum. Methods and apparatus for texturing yarn are well known. One such method is described in U.S. Patent No. 4,908,919. In order to improve productivity, methods for texturing such yarns have included processing multiple ends of such yarns in a side-by-side relationship using a common rotating cooling drum. However using this side-by- side method of producing textured yarns provides the opportunity for a breakdown of a threadline in the process downstream of the drum to interrupt or breakdown adjacent threadlines, which is highly undesirable. Summary of the Invention A method for bulking a plurality of yarns traveling side-by-side that includes the steps of heating, stretching, and passing each of said yarns through a bulking jet then forming the resultant bulked yarn into a plug and cooling the plug on a rotating drum, withdrawing said bulked yarns from said plugs, and forwarding them in paths to a windup the improvement for capturing said bulked yarns when one or more of said yarns have been interrupted between said drum and said windup comprising: containing each of said bulked yarns in an open-ended tube extending along said yarn path from said drum toward said windup to prevent the yarn when interrupted from entangling with yarn in adjacent paths and interrupting adjacent yarns, and recapturing said yarn when interrupted from said tube by means of a vacuum applied to the outlet end of said tube by a jet moveable into and out of engagement with said outlet end. The jet is moved into engagement with the outlet end of said tube when a threadline motion sensor detects absence of the threadline between the outlet end of the tube and the windup. Brief Description of the Drawings Fig. 1 is a schematic illustration of a multi-end texturing process useful in the practice of this invention. Figs. 2-6 are schematic illustrations of the system showing recapturing and restringing a broken threadline downstream of the cooling drum. Fig. 7 is a cross-sectioned view of the outlet end 20a. of tube 20 showing a threadline cutter built into the outlet end to cut off the tail of a threadline downstream of jet 22. Detailed Description of the Illustrated Embodiment The process chosen for purposes of illustration in Fig. 1 includes a plurality of separate threadlines 12 being spun as filaments from a spinneret 10 and each threadline is passed around a series of feed rolls 14-14A to establish the spun denier of the undrawn filaments. A fixed amount of elongation in the threadlines 12 is obtained by setting the speed of draw rolls 16-16D with respect to feed rolls 9-9B to develop the final denier and physical properties of the threadlines 12. The threadlines are next forwarded to jet bulking devices 18. In the jets 18 the threadlines 12 are subjected to the bulking action of a hot fluid. The hot fluid exhausts with the threadline against a rotating drum 19 having a perforated surface on which the yarn cools to set the crimp. From the drum, each threadline in a crimped or bulked form passes to a series of open-ended tubes 20 which deliver each threadline to a package winder generally designated as 35. Figs. 2-6 illustrate the method for initial string-up of a threadline 12 from the drum 19 through the tube 20 or the recapture of a broken threadline contained in tube 20. As shown in Figs. 2 and 3, a jet 22 is moveable into and out of engagement with the outlet end 20a of table 20. The inlet end 20k of the tube 20 is adjacent the threadline on the drum. The jet 22 and its inlet end 22b is moved into and out of engagement with tube outlet 20a by means of a pneumatically powered a 2- axis mechanism (not shown) but represented by direction arrows 21 and 23. In Figs. 4 and 5 the threadline is captured by the jet 22 and transferred to waste receiver 24 through flexible tube 24a. Then the 2-axis mechanism is retracted horizontally from the outlet end 20a to expose the running threadline 12 which an operator can cut into a manual string-up gun 27 and proceed with the string-up procedure (Fig. 6 and Fig. 1) through centering guide 25, past a threadline motion sensor 26, around the take-up rolls 31, through an interlace jet 32 and let down rolls 33, through a finish applicator 34, to the winder 35. The threadline motion sensor 26 detects the absence of yarn between the tube outlet 20a and the windup and then activates the moveable jet 22 to engage the outlet end of tube 20. A cutter 40 built into the outlet end 20a of tube 20 cuts off the tail 12a of any threadline that may be trapped between the inlet of jet 22 and the outlet end 20a of tube 20. The cutter 40 is mounted on tube 20 and covered by sleeve outlet 20a. A spring 42 pushes sleeve outlet 20a over the cutter 40 to protect its cutting edge. The flared inlet 22b of jet 22 pushes broken end 12a against cutter 40 cutting it as the recapture jet engages outlet end 20a of tube 20. Thus, making a positive capture of threadline 12 possible.

Claims: What is claimed is: 1. In a method for bulking a plurality of yarns traveling side-by-side that includes the steps of heating, stretching, and passing each of said yarns through a bulking jet then forming the resultant bulked yarn into a plug and cooling the plug on a rotating drum, withdrawing said bulked yarns from said plugs, and forwarding them in paths to a windup the improvement for capturing said bulked yarns when one or more of said yarns have been interrupted between said drum and said windup comprising: containing each of said bulked yarns in an open-ended tube extending along said yarn path from said drum toward said windup to prevent the yarn when interrupted from entangling with yarn in adjacent paths and interrupting adjacent yarns, recapturing said yarn from said tube by means of a vacuum applied to the outlet end of said tube by means of a jet moveable into and out of engagement with said outlet end. 2. The method of Claim 1, including the additional step of sensing the presence of said bulked yarns between said tube and said windup and moving said jet into engagement with the outlet end of said tube in the absence thereof.

Inventors: POTTER JERRY FULLER, POTTER, JERRY, FULLER
Applicants: DU PONT, E.I. DU PONT DE NEMOURS AND COMPANY
Application year: 1995
Main classification: D02G1
IPC codes: B65H54, B65H67, D02G1, D02G3, D02J1