US3327462A - Yarn separating means - Google Patents

Description

W. K. WYATT YARN SEPARATING MEANS June 27, 1967 5 Sheets-Sheet 1 Filed June 17, 1965 A 770/?1VEY5.

W. K. WYATT June 27, 1967 YARN SEPARATING MEANS 5 Sheets-Sheet 2.

Filed June 1'7, 1965 I N VENTOR. l/l/LY/ii Jiifhfyail, 62w 6L0 June 27, 1967 w. K. WYATT YARN SEPARATING MEANS 5 Sheets-Sheet 5 Filed June 17, 1965 June 1967 w. K. WYATT 3,327,462

YARN SEPARATING MEANS Filed June 17, 1965 5 Sheets-Sheet 4 I N VEN TOR.

mz/iam/mmglam June 27, 1967 w. K. WYATT 3,327,462

YARN SEPARATING MEANS Filed June 17, 1965 5 Sheets-Sheet 5- I NVEN TOR.

v ads A T70/7/YEY5.

United States Patent 3,327,462 YARN SEPARA'HNG MEANS William Kirk Wyatt, Lansdale, Pa, assignor to Turbo Machine Company, Lansdale, Pa, a corporation of Pennsylvania Filed June 17, 1965, Ser. No. 464,797 7 Claims. Cl. 5734) This invention relates to means for controlling the separation of double-end (or multi-end) twisted yarn into divided or separate ends of yarn.

While the separating device of the present invention has other uses, an important use is as a component of apparatus used for false-twisting double-end thermoplastic yarns, and when used for this purpose, the invention represents a modification of the separating means shown in US. Patent 3,091,908, issued June 4, 1963, to G. A. Carruthers, and assigned to the assignee of the present application.

In one form of apparatus shown in the drawings of the Carruthers patent, conical withdrawal rolls are driven in timed relation with respect to the in-feed rolls so that the yarn between the withdrawal rolls and in-feed rolls is maintained under a limited and predeterminable amount of tension. The apparatus is preferably so operated that the peripheral speeds, at approximately the longitudinal centers, of the conical withdrawal rolls are equal to the peripheral speeds of the in-feed rolls, and in operation, the conical withdrawal rolls function automatically to compensate for any difference of yarn tension as may occur between the two single ends of the double-end yarn and tend to cause the point of separation to be maintained at substantially the same point.

While conical roll separating means, such as referred to above, operate very satisfactorily in false-twisting apparatus, they operate best when the yarn is supplied or fed through the apparatus at a rate substantially equal to that at which it is taken away. However, they may also be used satisfactorily for use in false-twisting apparatus in which the yarn is passed through a controlled tension device at the in-feed end and pulled through the falsetwist zone by conical nip rolls located at the output end, particularly where a tension-control means is provided.

The present invention provides a yarn-separating control device which stabilizes the yarn separation point when a controlled amount of tension is applied at the infeed end.

It has been found that slight differences in frictional resistance or drag tend ordinarily to occur, and that these cause one of the single ends of the twisted yarn to be withdrawn more readily than the other. Such variations in drag tend to cause the separation point to wander to one side or the other.

An object of the present invention is to prevent such undesirable occurrences from happening and to maintain or stabilize the separation point at a substantially fixed location irrespective of unavoidable variations in the frictional resistance offered to the individual single ends of yarn.

The invention will be clear from a consideration of the following detailed description of several embodiments selected for illustration in the drawing in which:

FIG. 1 is a perspective elevational view, partly diagrammatic, showing one specifi form of false-twisting apparatus embodying the present invention;

FIG. 2 is an enlarged front elevational view showing the front conical drive rollers which pull the yarn, and showing the yarn separating device of the apparatus of FIG. 1;

FIG. 3 is a side elevational view of the separating device, which also shows the mounting of the rear conical rollers;

FIG. 4 is a top plan view of the conical rollers appearing in the preceding figures showing also the mounting of the rear conical rollers;

FIG. 5 is a view in perspective showing a modified form of yarn separating device embodying features of this invention;

FIG. 6 illustrates in perspective another form of separating device according to this invention; and

FIG. 7 depicts diagrammatically yet another form of separating device embodying features of this invention.

The description which follows is phrased in specific terms in the interest of clarity. Such specific terms are not intended to limit the scope of the invention in any way but are intended only to describe specifically those forms of the invention that have been selected for illustration in the drawings.

Referring now to the specific form of apparatus of the present invention shown in FIG. 1, a pair of single ends of yarn 20 and 21 from supply sources 10 and 11 are pretwisted, as by hand, to form the double-end twisted yarn Y, which is passed through false-twist apparatus shown to include a tensioning device 12, a heater unit 13, and a cooling zone 14, which may be ambient air. The twisted double-end yarn Y then passes between and under a pair of laterally-spaced fingers 36, 37 which are part of the separation control device identified comprehensively by reference numeral 30. The individual single ends of yarn and 21 then separate and pass outwardly over and about guide spools 74 and 75, which are also part of the separating device 30. The single ends 20, 21, then pass down between the nips of oppositely disposed pairs of conical nip rollers 16, 18, and 17, 19. The single end of yarn 20 which passes through the nip of conical rollers 16, 18, passes through guide eye 46 down through reciprocating traversing guide 22 and on to a take-up roller 24. The single end of yarn 21 passes through the nip of conical rolls 17, 19, through guide eye 47, down through reciprocating traversing guide 23, and on to takeup roll 25.

Takeup rolls 24 and 25 are spring biased, by means not shown, and are driven peripherally by frictional engagement with a drive roller 26 which is illustrated as driven by electric motor through belt drives 41 and 42.

The front roll 16 and 17 of each pair of conical nip rolls is preferably provided with a surface of soft resilient rubber or other material having a high coeflicient of friction. The back conical rolls 18 and 19 may preferably have a smooth metal surface. The conical nip rolls 16, 18 and 17, 19 function to pull the yarn through the falsetwisting apparatus, against suitable tension supplied by device 12.

So far as the present invention is concerned, the conical nip rolls may be mounted for rotation and driven by suitable means other than as shown. In the preferred embodiment, the front conical rolls 16, 17 are mounted on a common shaft 48, shown as driven by belt 44 which in turn is driven by motor 40 through belt drives 41 and 43. Thus, in view of the common drive source 40, the speed of the conical nip rolls 16 and 17 has a relationship to the speed of the drive roll 26 which drives the take- up rolls 24, 25.

In the illustrated embodiment, the front conical rolls 16, 17 are shown supported by a hollow rectangular support member which projects horizontally forwardly from an upright plate 52 mounted on frame member 53 of the apparatus. Support member 50 has a circular base 51 which is adjustable angularly relative to plate 52 so that the orientation of the conical nip rolls may be adjusted.

An arm 54 is shown secured to, and extending horizontally forwardly from, the upper edge of the plate 52, and supports a vertically disposed plate 56 upon which is mounted the yarn separation control or stabilization device 30. Plate 56 is provided with a vertical slot 156 for adjusting plate 56 vertically, as by means of screw 57.

The separating device 36 includes a disc 53 which is pivotally supported On plate 56 as by an integral stud 59 having a spring-loaded wing nut 159. An inverted generally V-shaped spring-tensioned wire member 70 has a circular crotch portion which loops over and around the periphery of disc 58 and has a pair of arms 72 and 73 which extend downwardly and outwardly. At the lower extremity of each of the arms '72, 73 is a guide spool 74 and 75.

The arms 72, 73 are spring-tensioned outwardly, and are provided with a restraining collar 76 which embraces the arms 72 and 73 just below the disc 58. Collar 76 constrains the arms 72, 73 and maintains fixed (and adjustable) the lateral spacing of the guide spools 74, 75. The spacing between spools 74, 75 may be reduced by forcing the collar 76 downward and by holding the collar at its lowered position, as by the adjustable threaded stop bolt 176. A horizontally disposed U-shaped bracket 77 mounted on plate 56, and adjustable vertically, functions as a limit stop for the arms 72, 73, limiting the extent to which the arms may move in the plane of the arms, i.e., laterally relative to the double-end twisted yarn Y.

The rear conical rolls 18, 1? may be mounted for rotation and pressed against the surface of the front conical rolls by any suitable means. One suitable means is illustrated in FIGURES 1, 2, 3, and 4. As there shown, the rear conical rollers 18 and 19 are supported by L- shaped brackets 62 and 63. Bracket 62 is adjustably secured pivotally to the top surface of the hollow rectangular support member 50, as by screw 162, and extends outwardly and downwardly, as best seen in FIGS. 1 and 2, while bracket 63 is adjustably pivotally secured to the bottom surface of support member 50, as by screw 163, and extends outwardly in the opposite direction and upwardly.

Air cylinders 68 and 69, mounted on circular base 51, are adapted to press the brackets 62 and 63 forwardly, thereby to cause the brackets 62, 63 to pivot about their respective pivot points and thereby to urge the rear conical rolls 18, 19 against the forward conical rolls 16, 17. Piston 66 of air cylinder 68 abuts against a finger 64 which forms an integral part of bracket 62 and extends downward from the upper leg thereof. Piston 67 of cylinder 69 abuts against a finger 65 which is a part of bracket 63 and extends upward from the lower leg thereof.

Tension springs 71 and 71a are connected between upright plate 52 and the pivotal brackets 62, 63 for pulling the brackets pivotally rearwardly when the pistons 66 and 67 are retracted, thereby to withdraw the rear conical rolls 18, 19, from frictional engagement with the front conical rolls 16, 17.

The operation of the false-twisting apparatus of FIG. 1, and of the yarn-separating device of FIGS. 14 will now be described. Assume that the hollow rectangular forwardly-projecting support member 50 has been properly oriented by angular adjustment of the base 51, and that the spacing between the guide spools 74, 75 at the extremities of arms 72 and 73 has been adjusted so that the single ends of yarn 20 and 21 pass through the nips of the pairs of conical nip rolls 16, 18 and 17, 19 at a suitable point intermediate the ends of the conical rolls.

The rubber-surfaced front conical rolls 16 and 17, driven bythe electric motor through belt drives 41, 43 and 44, pull the single ends of yarn 20 and 21 downwardly over the guide spools 74, 75 and deliver the single ends through guides 46, 47, and 22, 23, to the take-up rolls 24, 25.

In the false-twisting apparatus herein illustrated, the single ends of yarn 20 and 21 are assumed to have been pretwisted so that a twist extends from the separation point S upwardly, in FIG. 1, through the cooling and heating zones 14, 13, and through the tension device 12 to the point of convergence P.

At the separation point S, the yarn passes through and then outwardly under a pair of forwardly extending spaced- apart fingers 36, 37. These fingers receive and oppose the upward thrust of the yarn and prevent the point of separation S from moving upstream, thereby maintaining point S at a fixed level.

So long as the frictional resistance opposing travel downstream of each end of yarn is equal, the point of separation S will remain laterally steady, midway between the guide spools 74, 75, If, however, the frictional resist ance or drag on one of the yarn ends is greater than that on the other, the yarn end suffering the larger drag or resistance will apply a greater laterally-inward and downward force to one of the guide spools 74, '75 than to the other. The greater force will cause wire structure 70 to pivot laterally (relative to the double-end twisted yarn as viewed in FIG. 2) and the nip point at which one end of yarn is pulled through its conical rolls which move closer to the small end of the rolls, and the nip point of the other end of yarn will move toward the larger diameter end of its conical rolls. For example, if at a given moment it requires more force to pull the right yarn end 21 than it does to pull the left yarn end 20, guide spool 75 will be forced to the left, as viewed in FIGS. 1 and 2, and the nip point at which yarn end 21 passes through its conical rolls 17, 19 will move toward the small end of these rolls. The inverted V-shaped wire structure 70 will thereupon be forced pivotally to the left, disc 58 rotating clockwise on its pivot axis 59. Since the spacing between guide spools 74, 75 is held fixed, the guide spool 74 will move to the left, causing the other yarn end 20 to pass through its conical rolls 16, 18 at a nip point closer to the large end of the rolls. This increases the pull on yarn end 20 and as a result an increased force is exerted laterally-inward (to the right) on spool 74 which opposes and tends to limit the movement of the wire structure 70 to the left.

When the pivotal movement of the structure 70, as above described, carries guide spool 74 to the left a sufficient distance to cause the pull on the left yarn end 20 to exceed that on the right yarn end 21, the structure 70 will begin a return movement to the right, and this movement to the right continues until the pull on the rig-ht yarn end 21 equals that on the left yarn 20. The action takes place quickly and serves quickly to stabilize laterally the point of yarn separation S.

To prevent the wire structure 70 from moving pivotally to such an extent that the yarn ends 20 or 21 are moved beyond the ends of the conical rolls, or to othe-r-- wise limit the range of the pivotal movement of wire structure 70, a limit stop is provided in the form of U-shaped bracket 77 mounted on the plate 56 and adjustable in the vertical direction in slot 156. If one or the other of the arms 72, 73 contacts one of the forwardly extending arms of bracket 77, further movement in that direction of the wire structure 70 is prevented.

As a further precaution against the yarn ends 20, 21 being moved beyond the ends of the conical rolls 1619, as for example in the event of improper mechanical adjustments to the yarn separating device, there is provided, in the apparatus illustrated in the drawing, a pair of mercury limit switches 80 and 81 mounted at opposing ends of a bracket 82 secured to the upper edge of disc 58. The mercury switches 80, 81 are opposin-gly disposed at inclined positions. Thus, when the wire structure 70 pivots more than a selected distance to the left and disc 58 is rotated clockwise more than a predetermined amount, the right mercury switch 81 becomes closed; whereas when the wire structure 70 pivots more than a selected distance to the right, thereby rotating disc 58 counter-clockwise more than a predetermined amount, the left mercury switch 86 becomes closed. Closing of either of the mercury switches energizes the relay 83 (FIG. 1) and causes the switch contact 183 to open, thereby deenergizing the motor 40 to stop the apparatus.

The advantages and features of the yarn separating device 30 of the present invention are by now no doubt understood. The device 30 allows the conical rolls 1619 to pull pretwisted double-end yarn from their individual sources through the heating and cooling zones 13, 14 (wherein the false twist is set) against a selected amount of drag or resistance introduced by the tension device 12, without allowing the yarn ends to run off one or the other end of the conical nip rolls. The device 30 functions to compensate automatically for any differences which may tend to occur in the drag or resistance which opposes travel of the separate yarn ends 20, 21 through the false twisting apparatus. The device 30 does this (1) by maintaining the ply separation point S substantially fixed in the vertical direction (this is done by the fingers 36, 37) and (2) by introducing a counter force which opposes shifting of the ply separation point in the lateral direction. As already described, it the resistance or drag on the right yarn end 21 should become greater than that on the left yarn end 20, the guide spool 75 will move to the left, as viewed in FIG. 1, thereby causing spool 74 to also move to the left. But movement of spool 74 to the left is opposed by the increased force required to pull yarn end at the faster velocity corresponding to the larger diameter of the conical rolls 16, 18 at the new nip point. Thus, the yarn separation point S tends to be stabilized laterally by the device 30. As added features, the device includes adjustment, stop limit, and protective features already referred to.

While the yarn separating device illustrated in FIGS. 14 and described above represents the presently preferred form, other forms may be used. Two such other forms are illustrated in FIGS. 5 and 6. The form illustrated in FIG. 6 is very similar to that of FIGS. 1-4 and will be described first.

In FIGS. 6, the arms 172, 173 which support the guide spools 74, 75 are horizontally disposed, rather than vertically disposed as in FIGS. 1-4. The arms 172, 173 are separate, rather than integral, and the spacing between the spools 74. 75 is adjustable, as by means of a highfriction bolt and lock nut assembly 158 which allows lowfriction pivotal movement of the V-struc-ture 172, 173 as a unit about point 158 while maintaining the selected fixed spacing between spools 74, 75. In other respects, the structure of FIG. 6 is basically similar to that of FIGS. 1-4. For example, the fingers 136, 137 of FIG. 6 correspond to fingers 36, 37 of FIGS. 1-4. These fingers are fixed in position laterally and maintain the yarn separation point S at a fixed level vertically.

In FIG. 5, the guide spools are omitted, being replaced by the non-rotatable fingers 274, 275, but this is a relatively insignificant difference over the structures of FIGS. l-4 and 6, previously described. The more significant difference in FIG. 5 is that the other pair of fingers 236, 237, which control the vertical level at which the yarn separation take place, are mounted on plate 27 0' for pivotal lateral movement, rather than being fixed as in the case of FIGS. l-4 and 6. As shown in FIG. 5, the guide fingers 274, 275, and also the fingers 236, 237 are mounted on and project forwardly from the lower edge portion of triangular plate 270 which is pivotally suspended at its upper corner as by a nut and bolt assembly 258 adjustably supported in the slot of a support member 256. The single yarn ends 20, 21 are taken from the yarn separation point S down between fingers 236, 23-7, then laterally outward in opposing directions, over and around fingers 274, 275, and then down to the nips of the conical pull rolls. The stabilizing action is similar in most respects to that already described in connection with FIGS. 1-4 and 6, but with the arrangement shown in FIG. 5, variation in the vertical level of the separation point S may occur in the event the lateral pivotal motion of the plate 270 is large.

FIG. 7 depicts graphically yet another arrangement in which the triangular plate 370, mounted for pivotal movement about pivot point 358, is provided with but two fingers 336 and 337. The fingers 336, 337 control the vertical level of the yarn separation point S.,They also serve the function of fingers 274 and 275 of FIG. 5. However, in the arrangement illustrated in FIG. 7, the conical drive rolls are not mounted on a common shaft, as is preferred, and as is the case in all of the previously described embodiments.

The stabilizing action in FIG. 7 is generally similar to that previously described and will by now be readily understood.

While the drawings show a twisted pair of yarns, it will be appreciated that multiple yarns may be processed or that more than one twisted set may be processed concurrently in a single apparatus. The yarns may vary widely in total denier and in number of filaments.

It will also be appreciated that, while the invention has been described in detail with reference to specific em bodiments thereof, many changes may be made without departing from the scope of this invention. For example, equivalent elements may be substituted for those shown and described, parts may be reversed, and certain features of the invention may be used independently of other features, all without departing from the spirit and scope of the invention as defined in the appended claims.

What is claimed is: I

1. In an apparatus for modifying heat-settable yarn filaments wherein said yarns are pretwisted and conducted in a tensioned condition longitudinally downstream through a heat-setting zone, and wherein withdrawal means are provided for drawing the heat-set yarns outwardly apart, said withdrawal means being automatically operative in response to variations of yarns feed positions to vary withdrawal rates in a manner to equalize the tensions of the yarns withdrawn, the combination which comprises stabilizing means having a pair of laterally spaced-apart guides arranged at opposite sides outwardly of the yarn path, each being arranged in guiding relationship with one of the separated yarns, said guide means being adapted to receive and oppose the downstream and laterally inwardly directed components of thrust of said separate yarns, support means arranged to support said guide means for unitary movement laterally back and forth according to the relative magnitudes of inwardly directed components of thrust, for changing said feed positions in response to differences sensed in said relative magnitudes; upstream-thrust-receiving means between said pair of laterally spaced-apart guides for preventing the yamseparation point from moving upstream; and stop means for limiting the lateral movement of said guid means.

2. In yarn modifying apparatus; spaced pairs of conical nip rolls through the nips of which pass, after separation, the first and second single ends of a doubleend twisted yarn, said conical rolls being adapted to pull said yarn under tension through a modifying zone in double-end twisted condition; and means for stabilizang the point at which the double-end yarn is separated into said first and second single ends, said stabilizing means including: first and second guide means spaced apart laterally, one on either side of the path of said double-end yarn, and about which the single ends of yarn are respectively passed enroute to the nips of the respective pairs of conical rolls, said first and second guide means being adapted to receive and oppose the downstream and laterally inward components of thrust of the said angle ends of yarn; pivotally-mounted support means for supporting said first and second guide means for unitary movement in one lateral direction or the other according to the relative magnitudes of the inward components of thrust, for changing the nip points in response to diiferences sensed in said relative magnitudes; means fixed mounted between said first and second guide means for receiving and opposing the upstream thrusts of said single. ends of yarn for preventing said separation point from moving upstream; and stop means for limiting thev lateral movement of said first and second guide means.

3. Apparatus as claimed in claim 2 characterized in that a power drive is provided for said conical nip rolls and in that switch means are provided mounted on said pivotal support means for shutting off the power drive when the pivotal movement reaches a predetermined limit.

4. In a false twisting apparatus in which left and right pairs of conical nip rolls are employed beyond the yarn separation point to pullseparately the single ends of pretwisted double-end yarn through an in-feed yarn tensioning device and through a false-twisting zone; a yarn separating device for controlling and stabilizing the point at which the double-end yarn separates into the two single ends, said device including: left and right yarn guides at fixed spacing laterally from each other, one on either side of the vertical plane of the double-end twisted yarn in the false-twist zone, for guiding the separate single ends of yarn to the nips of said left and right pairs of conical rolls respectively and for receiving. and opposing the laterally inward and downstream components of thrust of said single ends of yarn; pivotal support means supporting said left and right yarn guides for lateral pivotal movement while maintaining their spacing fixed relative to each other; fixed means disposed between, said left and right yarn guides for receiving and opposing the upstream components of thrust of said single ends of yarn for preventing movement of the separating point in an upstream direction; andmeans for adjusting the position.

of said fixed means.

5. Apparatus as claimed in claim 4 further. characterized inthat means are provided for adjusting the fixed spacing between said left and right yarn guides.

6. Apparatus as claimed. in claim- 5 further characterized in that stop means are pivoted for limiting the lateral pivotal movement of said left and right yarn guides.

7. Apparatus as claimed in claim 6 further characterized in that power drive mans are provided for driving said left and right pairs of conical rolls and in that switch means are provided for disconnecting said power drive when the lateral movement of said yarn guides reaches a preselected limit.

References Cited UNITED STATES PATENTS 2,987,869 6/ 1961 Klein 5734 3,091,908 6/ 1963' Carruthers 57-34 3,192,697 7/ 1 965 Carruthers 57-34' 3,237,391 3/ 1966- Carruthers 57-34 X 3,261,116 7/1966 Kunzle et al 2-872 X 3,261,155 7/1966 Kunzle' 2872 X 3,261,156 7/1966 Kunzle et al 2872 X FRANK J. COHEN, Primary Examiner.

D. E. WATKINS, Assistant Examiner.

Claims (1)

1. IN APPARATUS FOR MODIFYING HEAT-SETTABLE YARN FILAMENTS WHEREIN SAID YARNS ARE PRETWISTED AND CONDUCTED IN A TENSIONED CONDITION LONGITUDINALLY DOWNSTREAM THROUGH A HEAT-SETTING ZONE, AND WHEREIN WITHDRAWAL MEANS ARE PROVIDED FOR DRAWING THE HEAT-SET YARNS OUTWARDLY APART, SAID WITHDRAWAL MEANS BEING AUTOMATICALLY OPERATIVE IN RESPONSE TO VARIATIONS OF YARNS FEED POSITIONS TO VARY WITHDRAWAL RATES IN A MANNER TO EQUALIZE THE TENSIONS OF THE YARNS WITHDRAWN, THE COMBINATION WHICH COMPRISES STABILIZING MEANS HAVING A PARI OF LATERALLY SPACED-APART GUIDES ARRANGED AT OPPOSITE SIDES OUTWARDLY OF THE YARN PATH, EACH BEING ARRANGED IN GUIDING RELATIONSHIP WITH ONE OF THE SEPARATED YARNS, SAID GUIDE MEANS BEING ADAPTED TO RECEIVE AND OPPOSE THE DOWNSTREAM AND LATERALLY INWARDLY DIRECTED COMPONENTS OF THRUST OF SAID SEPARATE YARNS, SUPPORT MEANS ARRANGED TO SUPPORT SAID GUIDE MEANS FOR UNITARY MOVEMENT LATERALLY BACK AND FORTH ACCORDING TO THE RELATIVE MAGNITUDES OF INWARDLY DIRECTED COMPONENTS OF THRUST, FOR CHANGING SAID FEED POSITIONS IN RESPONSE TO DIFFERENCES SENSED IN SAID RELATIVE MAGNITUDES; UPSTREAM-THRUST-RECEIVING MEANS BETWEEN SAID PAIR OF LATERNALLY SPACED-APART GUIDES FOR PREVENTING THE YARNSEPARATION POINT FROM MOVING UPSTREAM; AND STOP MEANS FOR LIMITING THE LATERAL MOVEMENT OF SAID GUID MEANS.

Images