US3443292A

US3443292A - Apparatus for interlacing multi-filament yarn

Info

Publication number: US3443292A
Application number: US733476A
Authority: US
Inventors: Eugene L Davis Jr
Original assignee: EI Du Pont de Nemours and Co
Current assignee: EIDP Inc
Priority date: 1968-05-31
Filing date: 1968-05-31
Publication date: 1969-05-13
Anticipated expiration: 1986-05-13

Description

May 13, 1969 p/ [15, JR 3,443,292

APPARATUS FOR INTERLACING MULTIFILAMENT YARN- Filed May 31, 1968 INVENTOR EIICEIE LOANS, JR.

ATTORNEY United States Patent 3,443,292 APPARATUS FOR INTERLACING MULTI- FILAMENT YARN Eugene L. Davis, Jr., Mechanicsville, Va., assignor to E. I. du Pont de Nemours and Company, Wilmington, DeL, a corporation of Delaware Filed May 31, 1968, Ser. No. 733,476 Int. Cl. D02g 3/00; D04h 17/00; D01h 13/26 US. Cl. 28-1 6 Claims ABSTRACT OF THE DISCLOSURE A fluid interlacer device is disclosed as particularly useful for providing coherency in yarn which, as fed to the device, contains both slack filaments and taut, load-bearing filaments. A pair of fluid passages direct streams into a yarn passageway so that the streams intersect at the 0pposite wall of the yarn passageway. Another fluid passage directs a stream tangentially into the yarn passageway. The pair of intersecting streams opens the filament bundle and starts to interlace the filaments. The tangential stream rotates the yarn bundle, presenting different portions to the interlacing streams, and the excess length of slack filaments is taken up in loops or coils. Protruding portions of broken filaments are also interlaced into the bundle. The product maintains its unity without twist, has a uniform appearance, and may have a desirable bulkiness.

The present invention relates to apparatus for producing interlaced, multifilament yarn and is more particular- 1y concerned with gas or liquid interlacers having both intersecting and tangentially-directed fluid streams.

The improved fluid interlacer of this invention has a straight yarn passageway extending through a body member from a yarn inlet on one face to a yarn exit on the opposite face, a pair of fluid passages for directing fluid streams across the yarn passageway so as to intersect each other at the oppostie side of the passageway, and a third fluid passage for directing a fluid stream approximately tangentially into the yarn passageway. The pair of fluid passages is in substantial alignment with a plane perpendicular to the longitudinal axis of the yarn passageway and is located nearer to the yarn inlet than to the yarn exit. The third fluid passage is located nearer to the yarn exit than to the yarn inlet and directs fluid in substantial alignment with a plane perpendicular to the longitudinal axis of the yarn passageway. The effectiveness of the third fluid passage may be improved by curving it in the same direction as the vortex produced by it. This passage and the pair of fluid passages are preferably located near to and at ap proximately equal distances on each side of the midpoint of the yarn passageway. The yarn passageway is preferably of circular cross section and of a length at least several times the diameter thereof.

A thin string-up slot may be provided for inserting a running length of yarn into the yarn passageway. When such a slot is present, it intersects the yarn passageway tangentially for the full length of the passageway. The pair of fluid passages direct fluid streams to intersect at a portion of the yarn passageway wall which is not intercepted by the slot, and the tangential fluid passage is directed to produce a vortex which will retain the yarn in the yarn passageway rather than allow it to escape through the string-up slot.

Fluid interlacing devices have been described in Bunting and Nelson, US. Patent Nos. 3,110,151 and 3,115,691. Fluid twisters have been described in Breen and Sussman, US. Patent No. 3,079,745; Clendening, Patent No. 3,353,- 344; and Nagahara et al., Patent No. 3,206,922.. The use of a single vortex jet for interlacing was disclosed in the above Bunting and Nelson Patent No. 3,110,151. Fluid interlacing, fluid twisting and combinations of the two have been used to give synthetic filament yarns the handling characteristics of true twisted yarns by preventing filaments from separating from the yarn bundle. However, neither the fluid interlaceres nor the fluid twisters individually have been successful in giving satisfactory handling performance to yarns which have a substantial number of stretched or slack filaments. Since these filaments are longer than their neighbors, they remain projecting from the surface of the yarn bundle as arch-like loops after usual fluid interlacing or twisting operations. Broken filaments have also been diflicult to bind firmly into the yarn bundle with prior fluid apparatus.

The present invention provides apparatus useful for forming the excess length of stretched filaments into loops or coils, intermingling the excess length into the body of the yarn bundle, and interlacing the stretched and unstretched filaments together so as to produce a cohesive yarn of uniform appearance. The invention also provides apparatus which is useful for gathering protruding portions of broken filaments and interlacing them firmly into the yarn bundle. Other objects and advantages of the invention will become apparent from the disclosure and claims.

The invention will be more easily understood by reference to the drawings, wherein:

FIGURE 1 shows an isometric view of a preferred fluid interlacing apparatus of this invention,

FIGURE 2 shows a cross-section perpendicular to the yarn passage at section line 22 of FIGURE 1, the plane of the two intersecting fluid passageways, and

FIGURE 3 shows a cross-section perpendicular to the yarn passage at section line 33 of FIGURE 1, the plane of the tangential fluid passageway.

Referring to FIGURE 1, yarn passage 4 is a cylindrical hole bored through body 9. Two fluid passages 5 enter yarn passage 4 near the midpoint of the length of yarn passage 4. The fluid passages are supplied with fluid through plenum 6. Beyond the midpoint of the yarn passage, tangential fluid passage 7 intersects the yarn passage. It is supplied with fluid through tube 8. Slot 10 extends the full length of the yarn passage and provides access for a running length of yarn 11 to be threaded into the yarn passage.

Referring to FIGURE 2, the center lines of fluid passages 5 intersect each other at the opposite wall of the yarn passage. The included angle between the center lines is designated as a. The bisector of this angle a will pass through the axis of yarn passage 4. Interlacing fluid can be supplied to plenum 6 by any conventional means.

Referring to FIGURE 3, fluid passage 7 enters yarn passage 4 approximately tangentially and close to stringup slot 10. Passage 7 is straight and is supplied with fluid through tube 8, which may be either straight or curved. Passage 7 should be kept as short as possible when it is used with a curved supply tube. When tube 8 is curved, the center of curvature is on the same side of the center line of the fluid passage as the center of the yarn passage. Fluid passage 7 is preferably located close to the edge of slot 10 so that the maximum velocity of the fluid stream curtains the slot and prevents yarn from being blown out of passage 4 through the slot.

In a preferred embodiment, yarn passage 4 has a diameter of 0.25 inch and a length of 1.25 inches. The planes in which the two sets of fluid passages lie, indicated by section lines 2-2 and 33, are approximately 0.17 inch on either side of the midpoint of the yarn passage length. The diameters of fluid passages 5 are each 0.062 inch. Included angle a is 30. The diameter of fluid passage 7 is 0.065 inch diameter and the inside diameter of tube 8 is approximately the same or slightly larger. The radius of curvature of tube 8 is 0.56 inch. Slot 10, which is tangential to yarn passage 4, has a width of 0.031 inch.

In operating the apparatus of this invention, the fluid interlacer is preferably positioned between suitable yarn forwarding means, i.e., means capable of advancing the strand through the interlacer at controlled positive tension. Yarn is taken away from the jet at the same speed at which it enters. Preferably, the jet is positioned so that yarn 11 first encounters fluid passages and then fluid passage 7. The action of the high velocity fluid streams from passages 5 opens the yarn bundle, separates filaments from each other and starts to interlace them. Before the interlacing is completed, however, the filaments enter the vortex flow created by the approximately tangential fluid passage 7. This flow rotates the whole yarn bundle and divided portions of the bundle, thus presenting the bundle to different portions of fluid streams from passages 5. By the combination of actions taking place in these two zones, the excess slack in stretched filaments is taken up in loops or folds, and then the interlacing action of the taut filaments is completed and binds the slack filaments into the interlaced bundle structure, which maintains its unity due to frictional constraint between adjacent filaments even when the bundle is at zero twist. However, the product is not as compact as an otherwise similar interlaced yarn which does not contain slack filaments and a desirable bulkiness may be imparted by intermingled slack filaments. In the present product, the taut, load-bearing, unstretched filaments do not form loops. There is little or no change in tenacity of the yarn after jet processing.

A surprising feature of this apparatus is that, when all of the fluid passages receive fluid at the same pressure, the majority of the fluid leaves the fluid interlacer at the end of the yarn passage which is closer to the tangential fluid inlet. This occurs in spite of the fact that all fluid passages lie in planes perpendicular to the yarn passage, that fluid passages are nearly equally distant from the two ends of the yarn passage, and that the majority of the fluid enters the yarn passage through the fluid passages 5. The forwarding action of this flow pattern apparently aids in gathering and folding the excess filament slack while the interlacing action is completed.

Preferably, interlacing is carried out as an adjunct to one or more of the common textile operations such as packaging, etc., thereby taking advantage of existing yarn forwarding means. The minimizing of slack filament loops protruding from the yarn bundle and the increased coherency of the entire structure provide greatly improved handling properties to the yarn in textile operations.

I claim:

1. In apparatus for fluid treatment of multifilament yarn to interlace the filaments, an improved fluid interlacer comprising a body member having a straight yarn passageway which extends from a yarn inlet on one face of the body member to a yarn exit on the opposite face, a pair of fluid passages for directing fluid streams across said passageway to intersect each other at the opposite side of the passageway, the two fluid passages being in substantial alignment with a plane perpendicular to the longitudinal axis of said yarn passageway and located nearer to the yarn inlet than to the yarn exit, and a third fluid passage for directing a fluid stream approximately tangentially into the yarn passageway in substantial alignment with a plane perpendicular to the longitudinal axis of the yarn passageway, said third fluid passage being located nearer to the yarn exit than to the yarn inlet.

2. Apparatus as defined in claim 1 wherein said yarn passageway has a circular cross section and a length at least several times the diameter thereof.

3. Apparatus as defined in claim 1 wherein said pair of fluid passages and said third fluid passage are located near to and at approximately equal distances on each side of the midpoint of the yarn passageway.

4. Apparatus as defined in claim 1 wherein the center lines of said pair of fluid passages intersect at the opposite wall of the yarn passageway.

5. Apparatus as defined in claim 1 wherein said third fluid passage is curved before it enters the yarn passageway.

6. Apparatus as defined in claim 1 wherein said body member has a thin string-up slot for inserting a running length of yarn into the yarn passageway, said slot intersecting the yarn passageway tangentially for the full length of the passageway sothat the fluid streams from said pair of fluid passages intersect at a portion of the yarn passageway wall which is not intercepted by the slot, and so that the tangential stream from said third fluid passage retains the yarn within the yarn passageway.

References Cited UNITED STATES PATENTS 3,079,745 3/1963 Breen et a1. 5734 3,110,151 11/1963 Bunting et a1. 57157 3,115,691 12/1963 Bunting et a1. 281 3,206,922 9/1965 Nagahara et al. .0.-- 57-34 XR 3,262,179 7/1966 Sparling 281 3,333,313 8/1967 Gilmore et al 28-1 3,353,344 11/1967 Clendening 5734 JOHN PETRAKES, Primary Examiner.

U.S. Cl. X.R.