US3814341A

US3814341A - Yarn winding apparatus

Info

Publication number: US3814341A
Application number: US00395229A
Authority: US
Inventors: F Dickson; W Williams
Original assignee: EI Du Pont de Nemours and Co
Current assignee: EIDP Inc
Priority date: 1973-09-07
Filing date: 1973-09-07
Publication date: 1974-06-04
Anticipated expiration: 1991-06-04
Also published as: GB1433300A; JPS5053636A; FR2243137B1; DE2442683A1; CA1026298A; FR2243137A1; NL7411877A

Abstract

A yarn windup having two abutting yarn package supports per chuck in which two yarns are held near the abutting ends of the supports by retractable guides until the yarns are cut by a cutter. Transfer tails are then wound as the retractable guides are moved away from yarn engagement releasing the yarn into traverse guides to begin normal traverse winding. Optionally, the retractable guides are shaped so that during release of the yarn, they momentarily move the yarn slightly toward the abutting ends of the tubes to cross over and trap the cut yarn ends.

Description

June 4, 1974 United States Patent [191 Dickson, III et al.

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BACKGROUND OF THE INVENTION This invention concerns winding yarns or threads, more particularly, winding a transfer tail automatically as threadlines running at high speed are severed and begin winding onv packages.

' When winding yarn on a package, it is generally desirable to provide an initial wrap in the form of a short helix on a package support tube outside the package area. This wrap is commonly referred to as a transfer tail. Means for winding such tails automatically on a single package are known; for example, from Jackson U.S. Pat. No. 3,097,804 and Vanneman U.S. Pat. No. 3,166,262. A method of applying two running threadlines on two yarn package ltubes on the same chuck is known from, for example, Pabis U.S. Pat. No. 3,276,704 and in the latter patent, the yarn is positively attached to the package tube by entrapping the yarn in a slot cut partially around the tube. The extra cost of providing such slotted tubes is sometimes justified by increased sureness of grippingthe yarn; however, it would be desirable to avoid such cost if a well-secured transfer tail could be obtained otherwise. This added security of attachment presents a problem for the customer because the transfertail is so tightly wedged in the cut that it is difficult to dislodge. In addition, when the transfer tail of one package is tied to the beginning of another package, the yarn may accidentally become snagged in thc cut resulting in breakage ofthe yarn and failure to transfer yarn from the exhausted package to a new full package. Furthermore, when two or more yarns are handled simultaneously, it is desirable to find simpler ways of threading up the machine using less complex equipment.

SUMMARY OF THE INVENTION In a yarn winding apparatus including two surface driven tubular yarn package supports having abutting ends, a self-threading traverse guide associated with each yarn support through which yarn passes and which move yarn axially of said supports in a normal stroke length as a package is wound, and means for collecting and disposing said yarn when not being wound into a package, a mechanism for initiating wraps simultaneously on adjacent ends of abutting supports which overlap a severed length adjacent its end, said mechanism comprising: a pair of fixed guides positioned above said traverse guides atequal distances from the vertical plane of the abutting support ends, each of said fixed guides being positioned within the stroke'length ofa corresponding traverse guide; a cutting means position beyond said supports in alignment with said plane; a pair of retractable guides positioned between said fixed guides and said traverse guides at equal distances from said vertical plane between said plane and the end of said stroke length, said guides having yarn engaging slots opening toward and in proximal alignment with said cutting means; means mounting said retractable guides for simultaneous movement to and from a yarn engaging position and motive means coupled to said mounting means for imparting said move ment. Optionally, the retractable guides are shaped to move the running yarns momentarily toward the central abutting ends of the tubes as the guides retract, thus forcing the loops of yarn to cross the cut ends and trap them positively before the retractable guides release the yarns.

BRIEF DESCRIPTION OF THE DRAWINGS F IG, 1 is an isometric view of a typical windup showing a first pair of yarns strungup and ready for cutting.

FIG. 2 shows an overhead view of the yarn path from the retractable guides to the cutter in more detail.

FIG. 3 is a view similar to FIG. 2 showing an optional retractable guide arrangement for positively trapping the cut ends.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawing, it will be seen that the windup chosen for purposes of illustration includes generally as components thereof a` machine frame lr6, a pair of rotatable chucks 7, 20, a drive roll 6, and reciprocating traverse guides 26 through which yarn advances to package supports 8. A mechanism for initiating wraps simultaneously on abutting ends of package supports 8 is provided in association with the windup and includes a pair of fixed guides l positioned above traverse guides 26 at equal distances from the vertical plane of the abutting support ends, a pair of retractable guides 4 also positioned equal distances from the vertical plane of the abutting support ends but between guides 1 and guides 26. The yarn engaging slots of the guides 4 are equally spaced from the plane of the abutting support ends by a distance less than that from the plane to the nearest end of the normal stroke length of traverse guides 26. Preferably, the distance is between A0.10 and 0.30 inch.

'The distance between the cutting mechanism 10 and the axes of chucks 7, 20 is preferably greater than the maximum radius of a completed yarn package. A suitable cutter assembly is described in greater detail in Vanneman U.S. Pat.`No. 3,166,262. Two additional `

threadlines

13 and 14 are held temporarily in fixed guide l2 positioned beyond the end of drive roll 6 for later attachment to abutting yarn tubes on a second chuck 20. The running yarns are held in sucker gun 22 which carries them to a waste bin during stringup. It may be preferable to stringup the tubes on chuck 20 before those `on chuck 7, depending on the particular combination of machine elements.

Referring to FIG. 2,

yarns

2 and 3 are held in stringup position by retractable guides 4 so that they form paths 417 within about one-fourth inch from the abutting ends of yarn support tubes 8. Because the yarn is wrapped one and one-half times on tubes 8, the visible wraps 17 tend to lie on top of

yarn ends

2, 3 which are converging toward slot 9 in cutter bar 10.

As soon as the yarns are positioned in slot 9 of cutter bar 10, the operator moves the valve 11 (FIG. l) connected to a source of compressed air 4(not shown) which causes air to flow to both cylinders and 18. Cylinder 18 in cutter mechanism 10 causes blade 19 to sever both threadlines; at the same time cylinder 5 retracts piston rod 21 and guides 4 into the housing on top of machine frame 16. As guides 4 retract,

threadlines

2 and 3 contact the end of bumper plate l5 attached to frame 16 and guides 4 retract further, the yarns are released and move away from center to seek the shortest threadline distance between fixed guides l and tubes 8. ln so doing, they move off the surface of bumper plate l5 and into the space between machine frame 16 and drive roll 6 where they are picked up by traverse guides 26 to begin winding a normal package.

As the yarns move away from the tail winding position, they describe a helical path along tubes 8. The portion of this helical path which is not covered by the yarn package becomes the transfer tail. In the case of large yarn bundles with many filaments, which spread into a fairly wide band as they are pressed between tubes 8 and drive roll 6, an appreciable force is required to pull

threadlines

2, 3 from beneath wrap 17. When such yarns'are cut by cutter l0, the cut ends are immediately trapped by wrap 17 and become folded back and overwrapped with succeeding yarn.

FlG. 3 shows ari optional arrangement of retractable guides 4. The arrangement shown in FIG. 2 traps the cut yarns solely by superimposing succeeding yarn wraps on the path of the end to be cut. However, when small compact yarn bundles are being wound, running

ends

2, 3 may not be trapped firmly by wrap 17. ln this case, it is desirable to trap the cut ends more positively. ln FIG. 3, retractable guides 4' are shown with outer arms and yarn engaging surfaces 4a inclined inward toward the plane ofthe abutting support ends. As piston rod 2l retracts,

yarns

2 and 3 contact bumper plate l5 and then move toward each other as the guide surfaces converge. This forces yarn waraps 24 to move toward the abutting ends ofthe tube and cross over the cut ends, trapping them securely. As piston rod 21 retracts further. guides 4

release yarns

2 and 3 which move away from center in attempting to reach a shorter path from guides 1 to tubes 8. ln so doing, they move off the surface of bumper plate 1S and eventually are caught by traverse guides 26 to begin normal winding.

Before starting to string the machine, the operator moves air valve l1 to inactivate cutter l0 and to move piston rod 2l carrying retractable guides 4 toward drive roll 6 to a position for stringup.

The length of the transfer tail wound by this method is determined by the retracting speed of air cylinder 5, the proximity of bumper plate to the

threadlines

2 and 3, the distance between

threadlines

2 and 3 and the bumper plate as shown in FlG. 2, and the length and shape of the outer arms of guides 4. These are considered adjustable features to be selected at the discretion of the user.

Theretracting speed of air cylinder 5 may be regulated, for example, by a needle valve in the air supply line. Alternatively, a time delay may be introduced to start the retraction a definite time interval after the cutter operates.

A transfer tail wound by this method is easy to grip and unwind in the customers mill.

What is claimed is:

1. ln a yarn winding apparatus including two surface driven tubular yarn package supports having abutting ends, a self-threading traverse guide associated with each yarn support through which yarn passes and which move yarn axially of said supports in a normal stroke length as a package is wound, and means for collecting and disposing said yarn when not being wound into a package, a mechanism for initiating wraps simultaneously on adjacent ends of abutting supports which overlap a severed length adjacent its end, said mechanism comprising: a pair of fixed guides positioned above said traverse guides at equaldistances from the vertical pla-ne of the abutting support ends, each of said fixed guides being positioned within the stroke length of a corresponding traverse guide; a cutting means position beyond said supports in alignment with said plane; a pair of retractable guides positioned between said fixed guides and said traverse guides at equal distances from said vertical plane between said plane and the end of said stroke length, said guides having yarn engaging slots opening toward and in proximal alignment with said cutting means; means mounting said retractable guides for simultaneous movement to and from a yarn engaging position and motive means coupled to said mounting means for imparting said movement.

2. The mechanism as defined in claim l, each of said slots having a yarnengaging surface inclined toward said plane.

3. The apparatus as defined in claim l, wherein said motive means is a reversible pneumatic cylinder connected to a'supply of pressurized gas, said cylinder having a piston connected to a rod, said retractable guides being connectedto the rod.

=i :k a

Claims

1. In a yarn winding apparatus including two surface driven tubular yarn package supports having abutting ends, a selfthreading traverse guide associated with each yarn support through which yarn passes and which move yarn axially of said supports in a normal stroke length as a package is wound, and means for collecting and disposing said yarn when not being wound into a package, a mechanism for initiating wraps simultaneously on adjacent ends of abutting supports which overlap a severed length adjacent its end, said mechanism comprising: a pair of fixed guides positioned above said traverse guides at equal distances from the vertical plane of the abutting support ends, each of said fixed guides being positioned within the stroke length of a corresponding traverse guide; a cutting means position beyond said supports in alignment with said plane; a pair of retractable guides positioned bEtween said fixed guides and said traverse guides at equal distances from said vertical plane between said plane and the end of said stroke length, said guides having yarn engaging slots opening toward and in proximal alignment with said cutting means; means mounting said retractable guides for simultaneous movement to and from a yarn engaging position and motive means coupled to said mounting means for imparting said movement.

2. The mechanism as defined in claim 1, each of said slots having a yarn engaging surface inclined toward said plane.

3. The apparatus as defined in claim 1, wherein said motive means is a reversible pneumatic cylinder connected to a supply of pressurized gas, said cylinder having a piston connected to a rod, said retractable guides being connected to the rod.