US3461661A - Textile strand splice and method of forming same - Google Patents

Description

Aug. 19, 1969 M. F. IRWIN ETAL 3,461,661

TEXTILE STRAND SPLICE AND METHQD OF FORMING SAME I Filed May 16. 1968 United States Patent i 3,461,661 TEXTILE STRAND SPLICE AND METHOD OF FORMING SAME Malcolm F. Irwin, Philadelphia, and Frederick J. E. Hampel, East Greenville, Pa., assignors to Techniservice Corporation, Lester, Pa., a corporation of Pennsylvania Continuation-impart of application Ser. No. 645,410,

June 12, 1967. This application May 16, 1968, Ser.

Int. Cl. D06c 29/00 U.S. Cl. 57-442 8 Claims ABSTRACT OF THE DISCLOSURE Multifilament textile strands are spliced in an elongated chamber open at both ends and having a conduit for directing fluid, such as air and sometimes a resin, into the chamber to rotate circumferentially. The resulting splice has substantially constant diameter throughout.

This application is a continuation-in-part of our copending application, Ser. No. 645,410, filed June 12, 1967, now Patent No. 3,407,583. Reference is also made to our prior copending application, Ser. No. 609,463 filed Jan. 16, 1967 and now abandoned, of which the aforementioned application was itself a continuation-in-part.

This invention relates to splicing of textile strands composed of a plurality of filaments, i.e., principally multifilament strands, optionally having staple fiber components. The strands to be spliced together are overlapped, and the overlapped lengths are subjected to fluid rotating circumferentially thereof, which swirls the component filaments so that the strands will not be separated by applied tensions. Gun-like apparatus is provided by doing so and for applying an auxiliary adhesive agent when desired.

There is a considerable need for a simple, reliable, and cheap strand-splicing method to replace the old-fashioned method of tying and knotting, which has its own disadvantages, being conducive to snagging and breaking of the strands in ordinary textile processing. Some methods for joining or splicing textile strands together utilize solvents or actually melt component filaments and are limited to thermoplastic strands. Fluid jet methods whereby air or the like is blown at or through textile strands to entangle the component filaments have been devised also. These and other splicing methods are either so complex as to be too costly or are unreliable in their operation or results or produce an undesirable knot-like or other lump or enlargement at the splice itself or in part of the splice.

A primary object of the present invention is provision of a method for air-splicing textile strands.

Another object is provision of gun-like apparatus for practicing that method.

A further object is application of an adhesive agent to the spliced strands.

Other objects of the present invention, together with means and methods for attaining the various objects, will be apparent from the following description of a preferred embodiment and the accompanying diagrams.

FIG. 1 is a perspective view of an apparatus component useful according to the present invention;

FIG. 2 is a side elevation, partly in section, of apparatus of this invention including the component apparatus of FIG. 1 (sectioned transversely) and showing two strands therein about to be joined;

FIG. 3 is an end elevation of two such strands on an enlarged scale;

FIG. 4 is a fragmentary side elevation of a portion of the apparatus of FIG. 2, showing part thereof in alternative positions;

3 ,4 6 1,661 Patented Aug. 1 9, 1 969 FIG. 5 is a front elevation of the apparatus component of FIG. 1 with strands to -be joined in place;

FIG. 6 is a side elevation of a resulting splice of textile strands;

FIG. 7A is a sectional elevation (sectional shading omitted because of the small scale) through the splice talzien at 7A-IA on FIG. 6 on the same scale as FIG. 3; an

FIG. 7B is a similar sectional elevation therethrough taken at 7B7B on FIG. 6.

In general, the objects of the present invention are accomplished by the steps of juxtaposing the respective strands side by side, rotating fluid circumferentially of the juxtaposed strand lengths and thereby swirling the component filaments from both of the strands into an inseparable structure. The invention provides, as means for doing so, splicing apparatus comprising a tubular chamber, open at its opposite ends, with a slot extending one end to the opposite end and communicating with the exterior and with the chamber interior throughout its length, and having a fluid inlet extending from the exterior to the chamber interior between the ends.

FIG. 1 shows splicing chamber 11 in the form of a rectangular parallelepipedal block having longitudinal cylindrical bore 12 from end to end and slot 13 extending along the top from end to end and communicating with bore 12 throughout. Tube 14 fits into one side of the block midway of its ends and nearer theslotted top surface of the block than the bottom, terminating essentially tangentially of the cylindrical interior. Aflixed to the bottom and extending beyond the opposite ends of the block is strip 15, which has upstanding from each of its ends one of a pair of clips 16 extending past the bore axis.

FIG. 2 shows, in side elevation and partly in section, splicer 10 of this invention including (in transverse section) chamber 11 of FIG. 1 with two similarly sectioned strands 1, 1' shown at approximately the chamber axis. The strands are shown enlarged in FIG. 3, from which it can be seen that each contains numerous individual filaments. The near clip holding the strands outside the chamber is ahead of the sectional view in FIG. 2 and, therefore, not seen; the further clip, which normally would be visible at the rear, is omitted in the interest of clarity of the showing.

The splicer includes, in addition to the chamber and its attachments, gun 21 provided with intake fitting 22 at the base of grip 23. Supply hole 24 for air or other fluid (preferably gaseous) medium is attached to the intake fitting. Upper adjusting nut 25 limits the inflow of the air or other gas, which is initiated by depressing pivotally mounted trigger 20. Also carried by the gun is liquid container 31, which threads at its top into cap 32 afiixed to intake fitting 33 on barrel 29 of the gun. Lower adjusting nut 26 limits the inflow of liquid from the container to be propelled through and out of the barrel by the air or other gas.

FIG. 4 shows trigger 20 of the splicer gun in three successive alternative positions: A (solid line), B (dotdashed line), and C (broken line) corresponding, respectively, to the OFF position (no gas or liquid flowing), the BLOW position (gas only flowing), and the JET position (gas plus liquid flowing). Although the interior of the gun is not shown, a conventional paintspray gun may be used, in which the desired action and control are obtained by means of sliding valve elements which progressively move valve pistons (not shown) to uncover internal valves in the gas and liquid intake lines successively, the degree thereof being determined by the setting of the respective adjusting nuts, which vary the position or elfective length of the valve pistons.

In the practice of this invention, as will be apparent, a plurality (usually two but more can be used) of strands are juxtaposed by being overlapped for a length of at least as great as the spacing between clips 16 and are inserted through slot 13 in the top of the block comprising chamber 11 until they are received by the clips, which hold the overlapped strand lengths along substantially the axis of bore 12, as in FIG. 5. With the strands thus in place the trigger is depressed from position A (OFF) to position B (BLOW) for a short time (such as a few seconds) whereupon air (or other suitable gas, such as carbon dioxide or nitrogen) under pressure and optionally hot is injected into the chamber from gun barrel 29 through interconnecting tube 14. Rotated by the blast of gas so injected into the chamber, the juxtaposed strand lengths are swirled about to such an extent that filaments of each become interengaged with filaments of the other, with the result shown in FIG. 6.

The resulting strand structure is unitary, with increased diameter, along much or most of the length of the chamber bore, as so much interengagernent of filaments occurs that the original strand identity is lost there. Thus, FIG. 7A shows (in somewhat stylized form) a representative transverse cross-section through the splice at a location midway of the chamber ends, showing the component filaments sectioned essentially end-on. The central plane, in which this view is taken, as indicated on the view of the spliced structure in FIG. 3, is also the locus of maximum rotation by the jet. At this location the structure is somewhat looser than elsewhere in the splice, except at the ends, probably attributable to the fact that the filaments are essentially straight and parallel there where the induced twist (more properly false twist) in the strand reverses, more or less midway. The interstices at this central location are especially amenable to take-up and retention of adhesive when used. In FIG. 7B, which represents (similarly stylized) a representative transverse cross-section through the splice at a location intermediate the central portion and the end, the structure is generally similar to that shown in FIG. 7A but differs therefrom in exhibiting more elongated or elliptical filament cross-sections, and consequently somewhat reduced interfilament spacing, attributable to twist and interengagement of the component filaments. It will be understood that the relatively uniform stylization in representation of the individual filaments is merely an approximation and that in an actual splice greater variation in direction of major and minor axes in the respective generally elliptical sections would appear because of variation in filament orientation and in angle at which the respective filaments intersect the plane of the cut. Sectional shading is omitted from both FIGS. 7A and 7B because of size limitations.

If greater splice security is desired, as with strands of relatively few filaments or otherwise, further manual depression of the trigger to position C (JET) causes liquid resin to be atomized from container 31 and to be propelled into the chamber by the flow of air or other gas and onto the filaments, especially at the intermediate (FIG. 7A) position, where it solidifies to retain them in their spliced configuration. If desired, heat may be applied by any suitable means, as by a heating coil or infra red lamp (not shown) in the chamber, to cure the resin after application. Suitable resins will be apparent to those persons having ordinary skill in the art and may be of readily available melamine-formaldehyde, ureaformaldehyde, or epoxy type, for example. The splice should be retained in place with the air turned off or nearly so to avoid disturbance of the filament configuration during curing or setting of the resin. Hot air applied under low pressure at the BLOW position can be helpful in that regard.

Whether a resin or other adhesive is applied or not, the splice is removed from the chamber through the slot, and the unspliced ends or tails preferably are eliminated by cutting them off near their junction with the body of the splice. No special precautions are necessary in handling the spliced strand during performance of normal textile operations. The splicing process is quick and easy, and if desired the splicing apparatus can be provided with automatic timing means (not shown), which may be adjustable for different splicing periods, as for strands of dififerent composition, total denier, denier per filament, tension, or twist.

Unlike air-splicing methods of the prior art, the present invention is especially useful in joining strands having appreciable twist therein, i.e., one or more of the strands having more than one turn and as much as several turns or more per inch. During splice formation, at least when the strands have a like direction of twist, the twist is backed out at least partially (and usually reversed) on one side from an intermediate locus or plane, and while it is tightened somewhat on the other side therefrom the result is formation of a secure splice, which may be a bit unsymmetrical longitudinally with respect to that intermediate locus. When the twist in the unspliced strands is equal and opposite, the resulting splice is longitudinally symmetrical, i.e., the locus or plane of twistdiscontinuity in the false-twisted splice configuration is centrally located. Of course, the splicing process of this invention works as well on strands having little or no initial twist.

Nor is it necessary to increase or reduce tension in the strands to be joned, as untensioned strands may be treated at low fluid pressures or resulting velocities, and the flow may be increased in accordance with increasing strand tension. It often is desirable to start the fluid flow at a low pressure or rate and to increase it markedly during the formation of each splice as the swirling action takes place. While upon cessation of the fiow the false-twisting action ceases, and upon release from the splicer the induced false-twist is largely nullified, something of a twist-discontinuity usually remains at the intermediate locus in the splice, and minor twist-discontinuities may occur at each end of the spliced portion as it tends to but cannot quite assume the twist (or lack of it) in the adjoining single strand lengths.

Unlike previous splicing methods, whether they relied upon solvent or thermal softening or air entanglement, the present invention does not produce a relatively enlarged nub or knot-like structure at the center of the splice but provides a splice having its intermediate or twist-discontinuity (usually twist-reverseal) portion more nearly like that of the starting strands. The component filaments at such intermediate location are relatively parallel and although they naturally tighten under tension they are as disengageable or relatively loose under tension-free conditions as in the original strands under like conditions. The splice diameter is substantially uniform throughout. When resin or other adhesive is added it flows info the intermediate portion of the splice primarily, where it adheres and solidifies, without forcing the filaments apart and so enlarging the splice.

Other advantages and benefits of practicing the present invention in accordance with the disclosure of a preferred embodiment and modifications therein, as suggested, will be apparent. The respective starting strands cannot be reconstructed from the spliced structure even in the absence of adhesive binding except by painstaking manual separation of the individual filaments to permit restoration of them to their original positions. Ordinary textile processing tensions will not separate it into the two original strands either. Excessive tensions may break individual filaments or even all the filaments before separation of the splice itself.

The claimed invention:

1. In the air-splicing of a plurality of multifilament textile strands having appreciable twist therein, the improvement comprising rotating air circumferentially about lengths of the respective strands juxtaposed side by side, thereby false-twisting at least part of the juxtaposed lengths thereof in opposite directions from a longitudinally intermediate locus thereon and swirling filaments from each strand into interengagement with filaments from the other strand at locations flanking the intermediate locus.

2. The method of claim 1 wherein the false-twisting step forms a twist-discontinuity at the intermediate locus.

3. The method of claim 1 wherein the twist-discontinuity is a twist-reversal.

4. Textile strand splice of a plurality of multifilament strands, the splice being characterized by substantially constant diameter throughout and having an intermediate portion with a looser structure than the portions flanking the intermediate portion.

5. Textile strand splice according to claim 4, wherein the intermediate portion exhibits a twist-discontinuity.

6. Textile strand splice according to claim 5, wherein the portions flanking the intermediate portion exhibit oppositely directed twist.

7. Textile strand splice comprising a plurality of multifilament textile strands extending in opposite directions from portions of each strand constituting the splice, with an intermediate portion of the splice being characterized by filaments of the respective strands extending substantially straight and parallel to one another, and with portions of the splice flanking the intermediate portion being characterized by filaments of each strand interengaged with filaments of each other strand 8. Textile strand splice according to claim 7, wherein at the flanking portions of the splice the filaments are in swirling engagement.

References Cited UNITED STATES PATENTS 2,895,285 7/1959 Hilbert 57-34 XR 2,985,995 5/1961 Bunting et a1. 57-140 3,262,179 7/1966 Sparling 57-34 XR 3,339,362 9/1967 Dodson et a1. 57-159 3,274,764 9/1966 Gonsalves 57-142 3,306,020 2/1967 Rosenstein 57-22 3,334,477 8/1967 Morin et al.

FOREIGN PATENTS 824,742 12/1959 Great Britain. 956,992 4/1964 Great Britain.

DONALD E. WATKINS, Primary Examiner US. Cl. X.R. 57-159

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