US3839853A

US3839853A - Apparatus and method for continuously drawing and texturing yarn

Info

Publication number: US3839853A
Application number: US00097726A
Authority: US
Inventors: Kenzie P Mc
Original assignee: Fiber Industries Inc
Current assignee: Celanese Corp
Priority date: 1970-12-14
Filing date: 1970-12-14
Publication date: 1974-10-08
Anticipated expiration: 1991-10-08

Abstract

1. AN APPARATUS FOR CONTINUOUSLY DRAWING AND TEXTURING CONTINUOUS FILAMENT SYNTHETIC HEAT-SETTABLE YARN INCLUDING A. MEANS FOR SUPPORTING YARN SUPPLY SOURCES, B. SPACED APART DRAW ROLLS OPERATING AT DIFFERENT SURFACE SPEEDS TO DRAW THERE BETWEEN PAIRS OF YARNS WITHDRAWN FROM SAID SUPPLY SOURCES, C. MEANS TO TWIST TOGETHER THE YARNS OF EACH PAIR OF YARNS, D. YARN HEATING MEANS FOR THEREAFTER HEATING PAIRS OF YARN WHILE IN TWISTED-TOGETHER CONDITION, E. MEANS FOR THEREAFTER SEPARATING THE TWISTED YARNS COMPRISING A FIRST PAIR OF YARN DRIVEN GROOVED ROLLER THREAD GUIDES ENGAGEABLE BY THE YARNS UPON SEPARATION AND A SECOND SET OF YARN GROOVED ROLLER THREAD GUIDES POSITIONED BELOW SAID FIRST SET OF GROOVED THREAD GUIDES.

Description

United States Patent [191 McKenzie 57/157 TS X Wyatt 57/157 TS X 3,475,896 11/1969 Gibson et 3,422,613 1/1969 Berger et 3,327,462 6/1967 57/34 HS 3,423,924 1/1969 Comer et a1. 57/157 TS 3,091,908 6/1963 Carruthers......... 2,987,869 6/1961 Klein.................,.........

[ APPARATUS AND METHOD FOR CONTINUOUSLY DRAWING AND TEXTURING YARN [7 51 Inventor: Phillip E. McKenzie,

Winston-Salem, NC.

Assignee: Fiber Industries, Inc.,

Glarkme, Primary Examiner-Donald E. Watkins Attorney, Agent, or Firm-Parrott, Bell, Seltzer, Park & Gibson [22] Filed: Dec. 14, 1970 ABSTRACT [21] Appl. No: 97,726

tus includes means for coordinating the drive of the yarn drawing section with the drive of the yarn texturing section of the machine.

References Cited UNITED STATES PATENTS SW15. TS 2 Claims, 10 Drawing Figures 2,890,568 W1llens 2,896,395 7/1959 Fink............... 3,261,154 7/1966 Michalek INVENTOR. PmLuP ET. MEKENZJ r: 7%,

Jag/a o! ATTORNEYS am mam 3,839,863

mm 2 M s Jig-2 INVENTOR: PHHJJP E: M KENZHE 80 $00 A MMMJ%MM ATTORNEYS mamas Fmmwnm 8mm SMEI 3 0F 5 D INVENTOR:

PmLuP Er. MQK w Wfiaezdigw,

ATTORNEYS PAIENIEunm slam SHEET 0? 5 mwflOkOi ZO E INVENTOR: H \..L\ P MQK ATTORNEYS mm @m mQ U TE 1.? w mm, Mm? w r wm :fi

APPARATUS AND METHDD FOR CUNTHNDDUSLY DRAWING AND TEXTIUMNG YA The present invention relates generally to an apparatus and method for simultaneously drawing pairs of synthetic thermoplastic yarns and then texturing the yarns in a continuous process and more particularly to such a process which includes texturing by twisting pairs of yarns together, heat-setting the twistedtogether yarns, and separating the yarns. This apparatus and method imparts a high degree of permanent crimp or curl to the yarns.

Machines are commercially available for texturing thermoplastic textile yarns by twisting pairs of yarns to gether along a certain distance, heat-setting these twisted-together yarns and then separating the same. In all known machines of this type, pairs of yarns which have previously been drawn in a separate operation are utilized. The drawing process takes place concurrently with or soon after the yarn is formed by extrusion and the drawn yarns are wound onto suitable support tubes which provide the supply packages for this type of yarn texturing machine. It will be appreciated that it is difficult to draw yarns uniformly when they are extruded and thereafter drawn at different times. Even if the yarns are uniformly drawn, they remain on the supply packages for variable lengths of time before they are used.

During the time these supply packages are stored, the retractive forces in the yarns tend to return the yarns to a partially drawn condition. Also, these retractive forces act differently on different lengths of the yarn, depending on the position a particular length of yarn occupies on the wound supply package. For example, yarn lengths positioned near the inner core of the package are not retracted to the same degree as those yarn lengths which occupy the outer layers of the package. Thus, drawn yarn which is wound on a supply package does not have completely uniform characteristics throughout its length so that a subsequent texturing process will not produce completely uniform crimp or curl to the yarn. Also, when drawing has taken place a considerable length of time before the yarn is textured, the molecules become set in the drawn condition and it is more difficult to reorientate these molecules during a subsequent texturing operation which imparts a crimped or curled deformation to the yarn.

One factor limiting the speed of operation of twisted yarn texturing machines is the difficulty of withdrawing drawn yarns from the supply packages at very high speeds. As the speed of operation of the machine is increased, the speed of withdrawal of the yarn from the supply packages increases and the variation of yarn tension becomes greater, depending upon the portion of the supply package from which the yarn is being withdrawn. Thus, in practice the speed of yarn withdrawal from the supply packages has been limited to avoid such undue tension variations, snarling, excessive ballooning, yarn breakage, etc., which might occur if the yarn is withdrawn from the supply packages at too high speeds.

It is an object of the present invention to provide an apparatus and method for continuously drawing and texturing pairs of thermoplastic yarns to impart uniform crimp and curl to the yarns and to provide enhanced stretch and elastic recovery to fabrics formed of these yarns.

it is another object of the present invention to provide an apparatus and method for continuously drawing and texturing pairs of thermoplastic yarns whereby the undrawn yarn is withdrawn from the supply packages at a lesser speed than the speed at which the yarns are textured to thereby permit a substantial increase in the texturing speed while maintaining the speed of withdrawal of the yarn from the supply packages at a level well below the upper limit.

The simultaneous drawing of the pairs of yarns immediately preceding the texturing step insures the uniform drawing of the pairs of yarns which are twisted together in the subsequent texturing process. Also, the molecules of the freshly drawn yarns are still partially in the transition state and are somewhat mobile so that they may be more easily reorientated and permanently set while the yarns are deformed by being twisted together.

The freshly drawn yarns have uniform characteristics throughout their lengths because they are not wound onto an intermediate supply package where the retractive forces act differently on different lengths thereof.

In accordance with the present invention, the draw-- ing process has been combined with the texturing process wherein at least two yarn ends are drawn, twisted together and heat-set in a continuous operation. The apparatus includes means for withdrawing undrawn pairs of yarn from supply packages on a creel positioned behind each texturing station; means for drawing the pairs of yarn uniformly to the desired degree; means for thereafter texturing the yarns by twisting the yarns together and heat setting the twisted yarns; and means for separating the yarns and taking the individual yarns up on suitable packages. The speed of the op eration of the drawing section is coordinated with the speed of the operation of the texturing section. Although the texturing process is described in connection with the twisting together of pairs of yarns, it is to be understood that three or more yarns may be twisted together, heat-set and then separated.

Since the yarn moving directly from the drawing operation to the texturing operation is still somewhat heated and the molecules are in a mobile condition, the crimp or curl imparted by the texturing process is more permanent and may be more easily applied than if the molecules in the yarn were completely set, as they would be if the yarn had been drawn a considerable time before the texturing process. The draw rolls provide a positive feed input to the texturing section so that the yarns are fed to the texturing section under completely uniform conditions with no variations in tension. The positive feed draw rolls thus eliminate the tension variations caused by withdrawing the yarn from the supply packages, regardless of thespeed the yarn is withdrawn.

In accordance with the invention, yarns are under positive coordinated control throughout the drawing, texturing, and take-up sequences of procedure. This results in a more efficient, better running, precisely functioning machine, producing better quality yarn.

The invention also achieves substantial economics resulting from increased production at lower costs. By combining the drawing and twisted yarn texturing operations into a single continuous process, thecost of texturing is reduced by elimination of the intermediate step of winding the drawn yarn onto supply packages with the attendant problems of handling. Also, since the yarns are substantially elongated in the drawing process, the speed of yarn travel through the texturing operation may be greatly increased, by as much as 50 percent to 100 percent or more. The combined process also produces yarn having enhanced stretch characteristics and fabrics formed of this yarn have enhanced elastic recovery. Further, the yarn has more uniform characteristics throughout its length, such as crimp and curl, reaction to heat, affinity to dyes, stretchability and recoverability. I

Other objects and advantages of the present invention will become apparent in connection with the following detailed description of the invention which is given in connection with the drawings, in which:

FIG. I is a fragmentary front elevational view illustrating both end portions and one complete yarn texturing station of a yarn texturing machine of the present invention;

FIG. 2 is a transverse vertical sectional view taken substantially along the line 2-2 in FIG. 1;

FIG. 3 is a fragmentary vertical sectional view taken substantially along the line 3-3 in FIG. ll;

FIG. 4 is a fragmentary rear elevational view looking at the left-hand side of FIG. 2;

FIG. 5 is a fragmentary vertical sectional view taken substantially along the line 55 in FIG. 2;

FIG. 6 is an enlarged horizontal sectional view taken substantially along the line 66 in FIG. 5;

FIG. 7 is an enlarged horizontal sectional view taken substantially along the line 7-7 in FIG. 5;

FIG. 8 is a somewhat schematic illustration of the manner in which the undrawn yarn is first drawn and then twisted together to texture the same;

FIG. 9 is an enlarged horizontal sectional view through the heater tube of the machine; and

FIG. 10 is an isometric view of one set of feed rolls and the yarn separating pulley supported thereabove.

Referring particularly to FIG. 8, the sequence of operations of the invention is illustrated with reference to a single texturing station of a combined drawing and texturing machine. Individual undrawn or incompletely drawn yarn ends Y-l through Y-4 are withdrawn from respective yarn supply sources, such as packages -23 and pass through individual guide eyes -28. These yarns are gathered together as they pass through guide eyes and 30' (FIG. 8). Pairs of the yarns, such as yarns Y-l, Y-2 and Y-3, Y-4 are joined together to form respective pairs of yarn ends, indicated Y and Y. These paired ends of yarn Y and Y are then guided to drawing means by a pair of guide pins 31 and a forked guide 32. The drawing means are illustrated by a first and second sets of draw rolls with a draw pin therebetween. The paired yarns pass initially beneath a spring loaded rubber-covered feed roll 33 which is resiliently urged into engagement with a steel drive roll 34, the

rolls

33, 34 forming the first set of draw rolls. The yarns Y and Y pass upwardly and are wrapped about a draw pin 35 and then downwardly and are wound around the second set of draw rolls, including a driven roll 36 and a separator roll 37. The pairs of yarns Y and Y may be maintained in separated condition as they engage the first and second sets of draw rolls and may converge as they pass around the draw pin 35 and draw roll 36. The yarns are elongated or drawn between the sets of draw rolls due to the differential in speed thereof.

As the pairs of yarns Y and Y leave the separator roll 37, they pass through respective yarn guides 40, 41 and downwardly beneath respective twist trapping means such as guide pulleys 42, 43. From the

pulleys

42, 43 the yarns pass upwardly through a suitable separator guide 45 and between positioning guide pins 36 as they start their upward movement through means for heat setting the twisted yarns broadly indicated at 50 (FIGS. 3 and 8). The heat setting means 50 is illustrated as a slightly curved heater tube having spaced yarn receiving grooves therein for directing the separated pairs of yarns Y and Y upwardly therethrough. At the upper end of the heater 50, the pairs of yarns Y and Y are directed over suitable upper and lower yarn guide rollers 52, 53 and then downwardly to yarn separating and twist trapping means, broadly indicated at 55. The yarn separator means 55 includes sets of yarn guide pulleys. After separation, the individual yarn ends (-1 through Y-4- are drawn downwardly by feed roll means such as pairs of feed rolls 60, 61 and 62, 63, through guides 64 and 65 and are wound onto take-up packages -73.

The pairs of yarns Y1 and Y-2 forming the paired yarn ends Y are twisted together with the desired number of turns between the guide pulley 42 and the separation point 55 while the pairs of yarns Y3 and Y-4 are twisted together between the guide pulley 43 and the separation point 55. These twisted-together pairs of yarns are spiraled about each other in a helical manner and are heat-set in this deformed condition as they move up the separated grooves of the heater 50.

This continuous process of drawing and texturing of the paired yarns insures that the yarns are positively fed in a uniform manner to the texturing section since the second set of draw rolls 36, 37 provide a positive input feed means for the texturing section. Also, the continuous drawing and texturing of the yarns provides other advantages. For example, the drawing of the yarns causes an orientation of the molecules along the longitudinal axis of the yarn and since the molecules have been recently orientated to this position, they are still mobile and may be easily reorientated while the pairs of yarns are twisted together as they pass over the heater 50. With a given twist, greater and more uniform crimp and curl is produced in the yarn than the crimp and curl which would be produced if drawing had not immediately preceded the texturing. Also, when drawing and texturing is carried out in two separate steps, the winding of the freshly drawn yarn onto a package causes the retractive forces to be unevenly applied throughout the length of the yarn from the inside of the package to the outside. Since the respective pairs of yarns Y-l, Y-2 and Y-3, Y-4 are simultaneously drawn to the same degree, their characteristics will be uniform throughout their respective lengths.

For purposes of illustration the invention is shown in association with a conventional twist texturing machine which has been modified in accordance with the present invention. The machine illustrated is of the type known as the Duotwist Texturing Machine manufactured and sold by Turbo Machine Company, Lansdale, Pennsylvania. It is to be understood that the present invention may also be practiced on other types of twisted yarn texturing machines wherein twisted together yarns are heat-set and then separated. The machine includes end frames 80, 81 (FIG. 1) and normally includes eight yarn texturing stations spaced along between these end frames. A control housing 82 is supported adjacent the end frame and a main drive motor 83 is supported thereon (FIGS. 2 and 4).

Drive belts 8d connect the drive motor 83 to one end of a stub shaft 85 which is suitably supported for rotation intermediate its ends on the end frame 86. A drive belt 86 drivingly connects the other end of the stub shaft 85 with a feed control shaft 9ft which extends from one end frame to the other and is suitably sup ported for rotation at each texturing station (FIG. 5), in a manner to be presently described. A drive belt 9i drivingly connects the other end of the stub shaft @5 with one end of a take-up drive shaft 92 (FIG. 2) which supports drive roll segments 93 spaced along the front of the machine and between the end frames 86, 81.

The take-up packages 76-73 at each station are wound onto respective take-up tubes 95, 96 which are in turn supported on rotatable mandrels supported at one end for rotation in the upper ends of swing arms 97, 98 (H6. 1). The lower ends of the swing arms 9'7, 96 are supported on a pivot shaft itltl which is suitably supported at opposite ends of the machine frames 86, hi. Counterweights 116i, E62 are supported on the lower portions of the swing arms W, 98 and tension springs W3 (F IG. 2) normally pull the upper end of the swing arms 97., 9 h inwardly so that the outer peripheral surface of the take-up tubes 95, 96 or the outer peripheries of the take-up packages 76-73 are held in driving engagement with the drive rolls 93 on the take-up shaft '92. This type of machine is normally set up to make a single package on each of the takeup tubes 95, 96. in the present illustration, pairs of packages are wound on each of these take-up tubes so that two pairs of yarns may be textured in what may be termed a double thread line arrangement.

The traversing guides are moved back and forth by grooved traversing rolls 165 which are fixed on a traversing drive shaft MP6 (HG. h). The guides 65 operate to wind the individual yarns Y-ll through Y-4 onto the supply packages -73 at each processing station of the machine. The drive shaft 106 is driven at variable rates by means of a variable drive unit 166a (FIG. ll) which includes a variable speed drive pulley 1636b. The drive unit lltlba is conventionally driven from the take up shaft 92. so that the rotational speed of the traversing shaft 106 is varied, relative to the speed'of the take-up shaft 92 in a predetermined manner to prevent overlying successive layers of wound yarn directly on top of the yarns in the succeeding layer. this traversingmechanism may be termed a wandering traversing system.

The feed control shaft is made up of a plurality of clutch control housings or units iii (FIGS. 5 and '7) which are interconnected by couplings. as indicated at lilh in FIG. 5. Bearings 109 are supported on the outer surfaces of each of the housings W7 and support opposite end portions of the feed control shaft 96 for rotation. A timing gear pulley illil is supported for rotation on the shaft W and is selectively drivingly connected thererto by a clutch iii. A timing gear drive belt i112 (FlG. 7) drivingly connects the timing gear pulley lillfl and a timing gear pulley Hi3 which is fixed to a drive shaft lllld. The feed rolls 61, 63 are fixed on opposite ends of the drive shaft lid and adjacent a support housing 115. The front feed rolls 60, 62 are supported for rotation in the upper ends of support arms which are connected to a support bracket i116. Adjustable resilient means is provided for urging the bracket 1116 and the front feed rolls 60, 62 inwardly into pressure engagement with the back feed rolls 61, 63 so as to draw the yarns therebetween as rotation is imparted to the shaft TM.

in accordance with the present invention, the conventionai stop motion has been replaced by means for stopping both the drawing means and the feed roll means simultaneously upon a yarn breakage. Such means are illustrated as including a forked stop motion wand 126 (FIG. 2) supported above the yarn separator means 55 and on the housing 1115 so that when one of the yarns breaks, this stop motion wand 126 will be moved by the other yarn to close a microswitch 121i and actuate the clutch ill to disconnect the drive be tween the feed control shaft 96 and the rear feed rolls 61, 63. This clutch till is engaged by means of a manually operable handle ll22 (FIGS. 11 and 7).

Preferably the machine is provided with an exhaust duct 1125 (M68. 2 and 3) having a branch pipe i126 positioned adjacent the upper end of each heater 50 to remove any fumes which arise from the heater 550 as the yarns are heat-set thereby.

The heater 50 has a pair of yarn receiving grooves for receiving the twisted-together pairs of yarns Y and Y therein (H6. 9) and is preferably surrounded with insulation material E27. A cover plate T28 encloses the yarn receiving grooves in the heater tube 50. A suitable heating medium, such as steam, is circulated through each of the heater tubes 56 by means of upper and lower branch lines 130, 131 (FIG. 3) which are respectively connected to longitudinally extending supply lines 1132 and 133 which extend to a suitable source of steam, not shown.

The series of upper and lower guide rollers 52, 53 are suitably supported for adjustment on a suitable support plate 1135. The conventional yarn supply creel usually mounted on posts 136 of the Turbo machine for supporting pirns of drawn yarn for direct passage to the guide pulleys d2, 43 has been removed. in accordance with the present invention, a special yarn creel is provided on the rear of the machine for supporting a plurality of supply packages of undrawn yarn at each texturing station.

As best shown in lFlG. 4, the yarn creel preferably includes a support frame 146 for the packages 26423 which is mounted by bearings for swinging movement on a post Mil. The lower end of the post Ml is supported on a longitudinal frame member M2 and the upper end is supported on a longitudinal support bar M3. The bearings of the frame Mil are supported by collars on the post Mil so that the frame Mi) may swing around substantially 180 from the position shown in H6. d so that the operator may easily donn and doff the supply packages 2-23 therefrom. The individual guide eyes Lid-2h are centered in front of each of the supply packages 26-23 and are fixed on the frame Milt. The yarn guides 30 and 30' are also supported on the frame 114m and provide two eyelets or guides for the pairs of yarns Y-l, (-23 and if-3, Y- -i. The guide pins Hill are suitably supported on the vertical frame members 1136 (FIG. 11).

A draw roll support plate 156) is suitably supported on and extends between pairs of the vertical supports 136 at each texturing station to provide support for the yarn drawing means. As shown in FIG. 6, the driven draw rolls 3d, 36 are fixed on one end of respective shafts 151, 152 which are in turn rotatably supported in suitable bearings on the plate 150 and a shelf 153.

Suitable means for driving the draw rolls 34, 36 are provided such as timing belt pulleys 154, 155 on shaft 152 and a timing belt 156 which drivingly connects the pulley 155 with a pulley 157 on the drive shaft 151.. A belt adjusting pulley 160 (FIG. is supported on one end of an arm 161 which is adjustably supported at its other end on one of the support plates for the shelf 153. The pulley 160 maintains the timing belt 156 in engagement with the

pulleys

155, 157 to impart rotation to the shafts 151, 152. It is noted that the pulley 155 is smaller than the pulley 157 and this ratio may be varied as desired to provide the desired degree of elongation or drawing of the yarns as they move from the first set of draw rolls 33, 34, around the draw pin 35 and to the second set of draw rolls 36, 37.

The upper rubber covered draw roll 33 is supported on one end of a shaft which extends through the plate 150 and the other end of the shaft is fixed in one end of a spring arm 163 (FIG. 5). A torsion spring 164 surrounds the pivot of the arm 163 and maintains the rubber covered roll 33 in resilient contact against the driven draw roll 34. A timing belt 165 extends around the pulley 154 and around a timing belt pulley 166 (FIG. 5) which is fixed on a jack shaft 167. Another timing belt 168 drivingly connects a timing belt pulley 169 with the timing belt pulley 110 (FIGS. 5 and 7).

Since the draw rolls are drivingly connected to'the same feed control drive shaft 90 as the feed rolls 6M3, the relationship between these rolls remains constant and may be varied by changing the diameters of the various drive pulleys which form this driving connection. Thus, it is possible to maintain any desired amount of underfeed or overfeed on the yarns as they pass from the draw rolls 36, 37 to the feed rolls 6t), 61, and 62, 63. Also, the clutch 111 operates to simultaneously drive both the draw rolls and the feed rolls and operates to simultaneously stop their rotation, when the clutch 111 is moved between the operative and inoperative positions.

The feed control drive shaft 91) and the clutches 111 of the Turbo machine were originally designed to stop and start only the feed rolls 60-63 and it has been necessary, in accordance with the present invention, to modify the clutch arrangement 111 and the supporting means for the feed control shaft 90. To this end, an additional bearing 175 (FIG. 7) is suppored on the inside of the clutch housing 107, and an extension 176 is connected to the bearing 175 with an additional bearing 177 being fixed thereto. Also, the operating faces of the clutch 111 have been modified in order to withstand larger loads when engaging and disengaging.

As best shown in FIG. 10, the pairs of twistedtogether yarns Y and Y are separated by the separating means 55 and the individual yarns Y-3 and Y2 pass beneath a first pair of grooved roller thread guides, such as guide pulleys 180 and 180 which are each provided with a yarn guide groove therein. The yarns Y-3 and Y-2 move downwardly and pass over a second pair of grooved thread guides, such as guide pulleys 181 and 181, each having yarn guiding grooves of different diameters so that the yarns are separated as they are drawn downwardly and between the feed rolls 62, 63. These

pulleys

180, 180' and 131, 181 are driven by the yarns and are suitably supported for independent rotation. After separation, the yarns Y1 and Y-4l are guided beneath a first pair of guide pulleys 182 (FIG. 8) and then over a second pair of guide pulleys 183,

which are supported for independent rotation and identical to corresponding pairs of guide pulleys 186, 186, 181, 181.

In accordance with the present invention, each section of the machine includes a drawing section and a texturing section with a common drive means. A clutch is interposed between the common drive means and the drawing and texturing sections so that the drawing and texturing operations may be simultaneously started and stopped.

In initially threading up the drawing and texturing station illustrated in FIG. 8, the yarns Y-l and Y-2 are drawn through the guide eye 30 to form the first yarn pair Y and the yarns Y-3 and Y-4 are drawn through the guide eye 30 to form the second yarn pair Y. The paired yarns Y and Y are passed around the guide pins 31, through the guide 32, beneath the draw roll 33, wrapped about the draw pin 35, wrapped about the second set of draw rolls 36, 37, separated and passed through respective guide eyes 411, 41, and then beneath the guide pulleys 42, 43. The yarns Y, Y are then passed upwardly adjacent the heater and maintained out of contact with the heater until the threading operation is completed. The yarns Y and Y are then guided over the respective rollers 52, 53 and the lower free ends are brought down to the separation point, adjacent the guide pulleys 180, 182.

The required amount of twist is then inserted in the first and second yarn pairs Y and Y by twisting them together the desired number of turns by any suitable means so that the paired yarns are twisted together from the separation point, back to the guide pulleys 42, 43. In order to obtain the same number of turns of twist per inch in each of the paired yarns Y and Y, it is necessary to impart a greater number of turns of twist in the paired yarns Y than in the paired yarns Y because the yarns Y follow a longer path of travel back to the guide pulley 42 than the path followed by the paired yarns Y back to the pulley 63.

When the proper amount of twist is inserted in the yarns Y and Y, the individual yarn ends Y-1 and Y2 of the paired yarn Y are separated and directed downwardly over the guide pulleys and through the feed rolls 66, 61 and 62, 63 and taken up on the respective yarn packages 70, 73. Also, the yarn ends Y-3 and Y-4 of the paired yarn Y are separated and directed downwardly over the guide pulleys and through the yarn feed rolls 60, 61, and 62, 63 and taken up on the

respective yarn packages

72, 71.

It is to be understood that the twist inserted in the paired yarns Y and Y remains trapped between the twist trapping pulleys 42, 63 and the separating means when the machine is in operation. As the yarns are continuously withdrawn from the supply sources 26-23 and taken up on the packages 711-73, the twisted together yarns are heat-set as they pass through the heating means 50.

If desired, the twist inserted in the yarns Y and Y may be in the same direction or in opposite directions and the yarns Y-l, Y-4 and Y-3, Y-2 may be taken up together on single packages rather than individual packages, as illustrated in FIG. 8. When the paired yarns Y and Y are initially twisted in opposite directions, they will each produce individual yarns having torque in opposite directions, that is, yarns having torque in S and Z directions. In this case, when the yarns Y-1, Y-4 and Y-3, Y-2 are taken up together, the

yarn on each package will have balanced torque. With suitable guide means, it is possible to take up the yarns Y-i, Y-Z and Y-3, Y-d together so that parallel yarn ends taken up on one package will each have torque in the one direction while parallel yarn ends taken up on the other package will each have torque in the other di rection.

As a specific, but non-limiting, example of the pro cessing of a particular type yarn, undrawn or raw nylon 66 monofilament yarns of about 60 denier may be drawn and textured in accordance with the present invention. The yarns are withdrawn from the supply packages 20-23 and the relative difference in surface speed between the first set of draw rolls 33, 36 and the second set of draw rolls 36, 37 is properly maintained to provide sufficient drawing of the pairs of yarns Y and Y to reduce the denier of each individual yarn to approximately denier. Thus, the draw ratio between the first and second sets of draw rolls is approximately 4 to 1. This size of yarn is particularly adapted for use in the knitting of relatively sheer fabrics, such as ho siery articles and the like.

in initially threading up this type of yarn, the paired yarns Y are twisted together with a total of 10,000 turns while the paired yarns Y are twisted together with a total of l 1,000 turns. The twist in these pairs of yarns extends from the separation point, back across the heater 50 and to the guide pulleys 432, 63 and provides approximately 100 turns per inch. The draw rolls 36, 37 and the feed rolls 60, 6ll and 62, 63 are rotated at a sufficient surface speed to move the yarn through the texturing section at a speed of approximately 2,000 feet per minute and to maintain the twisted together yarns under the desired amount of tension. The temperature of the heater is maintained at approximately 405 F. The relative difference in speeds between the feed rolls 60, 61 and 62, 63 and the take up drive roll segments 93 may be varied to wind the yarns onto the take-up packages under the desired degree of tension.

As another specific, but non-limiting, example, undrawn or raw nylon 66 yarn having three filaments with a total of approximately M denier is withdrawn from the supply packages -23 and the relative difference in surface speed between the first set of draw rolls 33., 36 and the second set of draw rolls 36, 37 is properly maintained to provide sufficient drawing of the pairs of yarns Y and Y to reduce the total denier of the yarn to approximately 118 denier. Thus, the draw ratio between the first and second steps of draw rolls is approximately 3.8 to I. This size of yarn is also particularly adapted for use in the knitting of relatively sheer fabrics, such as hosiery articles and the like.

In initially threading up this particular type of yarn, the paired yarns Y are twisted together with a total of 8,000 turns while the paired yarns Y are twisted together with a total of 9,000 turns. The twist in these pairs of yarns extends from the separation point, back across the heater 50 and to the guide pulleys 42, 43 and provides approximately 80 turns per inch. The draw rolls 36, 37 and the feed rolls 60., 61 and 62, 63 are rotated at a sufficient surface speed to move the yarn through the texturing section at a speed of approximately 2,000 feet per minute and to maintain the twistedtogether yarns under the desired amount of tension. The temperature of the heater is maintained at approximately 405 F. The relative difference in speeds be tween the feed rolls 60, 61 and 62, 63 and the take-up roll segments 02 may be varied to wind the yarns onto the take-up packages under the desired degree of tension.

it is to be understood that the number of turns of twist initially inserted in the paired yarns may be varied in accordance with the size or denier of the yarns and in accordance with the desired result to be achieved in the fabric produced by the yarn. As pointed out heretofore, the present invention has particular utility and ad vantage with the drawing and texturing of relatively fine denier yarns of the type used in producing light weight fabrics, such as hosiery articles and the like. These yarns usually range from about 7 to denier and are preferably textured by initially twisting the paired yarns together with about 30 to 150 turns per inch. However, the present invention is not limited to use with yarns within the deniers and fiber type usually referred to as hosiery yarns but may be used to process other types of yarns of various deniers for other end uses. For example, the yarns have particular utility for knitted or woven outerwear fabrics. Depending upon the type of yarn and the desired end use, the amount of twist, the speed of processing, and the amount of heat may be varied from those specifically set forth above.

in the drawings and specification, there has been set forth a preferred embodiment of the invention, and although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation.

ll claim:

it. An apparatus for continuously drawing and texturing continuous filament synthetic heat-settable yarn including a. means for supporting yarn supply sources,

b. spaced apart draw rolls operating at different surface speeds to draw there between pairs of yarns withdrawn from said supply sources,

c. means to twist together the yarns of each pair of yarns, I

d. yarn heating means for thereafter heating pairs of yarn while in twisted-together condition,

e. means for thereafter separating the twisted yarns comprising a first pair of yarn driven grooved roller thread guides engageable by the yarns upon separation and a second set of yarn grooved roller thread guides positioned below said first set of grooved thread guides.

2. The apparatus of claim ll wherein each of the second pair of grooved thread guides has yarn guiding grooves of different diameters.