US3520037A - Method and apparatus for producing wide webs from continuous multifilament yarns - Google Patents

Description

July 14, 1970 Filed Dec. 7, 1967 F. KALWAITES ETAL 3,520,037

METHOD AND APPARATUS FOR PRODUCING WIDE WEBS FROM CONTINUOUS MULTIFILAMENT YARNS 4 Sheets-Sheet l INVENTORSZ BY Q y 1970 F. KALWAITES ETAL METHOD AND APPARATUS FOR PRODUCING WIDE WEBS FROM CONTINUOUS MULTIFILAMENT YARNS 4 Sheets-Sheet 2 Filed D90. 7, 1967 IT QAS -INVENTORS: Fem K A444 /7's fP/vssz ATTORNEY.

y 1970 F. KALWAITES ETAL 3,

METHOD AND APPARATUS FOR PRODUCING WIDE WEBS FROM CONTINUOUS MULTIFILAMENT YARNS Filed D60- 7, 1967 4 Sheets-Sheet 3 INVENTORS: Fem/K A444 025s EPA/57 A nvaqs ATTO NEY.

14, 1970 F. KALWAITES ETAL 3,520,037

METHOD AND APPARATUS FOR PRODUCING WIDE WEBS FROM CONTINUOUS MULTIFILAMENT YARNS Filed Dec. 7. 1967 4 Sheets-Sheet 4 INVENTORS. FRANK A444 11/4/7219 EPA/5.5T A. Po/ 7,94 s

ATTOR EY.

United States Patent 3,520,037 METHOD AND APPARATUS FOR PRODUCING WIDE. WEBS FROM CONTINUOUS MULTI- FILAMENT YARNS Frank Kalwaites, Somerville, and Ernest L. Poitras, Cranbury, N.J., assignors to Johnson & Johnson, a corporation of New Jersey Filed Dec. 7, 1967, Ser. No. 688,857 Int. Cl. D02g l US. Cl. 28-1.5 11 Claims ABSTRACT OF THE DISCLOSURE A method and apparatus for producing wide webs from a plurality of continuous multifilament yarns comprising moving a plurality of continuous multifilament This invention relates to a method for producing webs or sheets of continuous filaments from a plurality of continuous multifilament yarns and to apparatus for carrying out such a method.

Fibrous webs are made from staple length fibers and/ or short length paper making fibers. Such webs are usually made by a card engine or by paper making or air laying machines. These machines produce a sheet or web of overlapping, intersecting, randomly arranged fibers. The web is held together by the frictional entanglement of the fibers and is quite weak. Nonwoven fabrics produced from these webs are usually produced by plying a number of webs together and applying adhesive to the laminate to bond it into a unitary structure.

The present invention contemplates a method for making a new type web of continuous textile filaments. The filaments run the entire length of the Web and may be relatively parallel or may be in various wavy type configurations. Nonwoven fabrics may be produced by laminating sheets or webs of these filaments together either parallel to each other or at angles to each other and if desired small amounts of adhesives may be applied to hold the plies together. Fabrics produced from such techniques have great strength in the direction of the filament alignment and also have a different hand and feel as compared to fabrics made from staple length fibers.

The desirability of such a filament fabric has been known, however, we have developed a method and apparatus for continuously, uniformly producing the base webs from which such fabrics may be produced.

In the fiber industry it is common practice to produce yarns from continuous filaments. The synthetic materials are extruded through a spinerette in continuous lengths and go through the necessary drawing and orienting operations as are commonly known. These filaments may in some instances be cut in various lengths to produce staple fiber from which which standard nonwoven fabrics or spun yarns are produced. In some instances if the filaments are large enough they may be used by themselves to produce a monofilament yarn and in still other instances when the filaments are quite small in diameter a plurality of these filaments are bundled together as extruded and form what is commonly termed a multifilament yarn. In some instances a twist may be 3,520,037 Patented July 14, 1970 ice applied to those multifilament yarns to improve the strength of the yarn. It is these multifilament yarns which have substantially zero twist from which we are able to produce webs of continuous filaments in accordance with the method and apparatus of the present invention.

In accordance with the present invention we take a plurality of the zero twist multifilament yarns and supply them in the same plane substantially parallel to each other. We move this sheet of yarns in a first path. We then change the direction in which this sheet of yarns is moving to a second path with the second path making an angle with the first path of less than 70 degrees. While the yarns are moving in the second direction we place them under a draft of at least 2 percent. This change in direction coupled with the draft places a curl or crimp in substantially all of the filaments of the yarns. The curled yarns are then moved in a third path and while being so moved are intermittently tensed and relaxed which disengages the curl in each filament from the curl in adjacent filaments. The yarns are intermittently tensed and relaxed a plurality of times to disengage filament curls and blend the filaments of one yarn with the filaments of adjacent yarns to produce a uniform wide sheet of continuous filaments.

In carrying our invention into practice the apparatus comprises means for supplying a layer of zero twist, continuous, multifilament yarns, said yarns being substantially parallel to each other and in the same plane, means for moving the yarns in a first path, means for moving the yarns at an acute angle of less than 70 degrees, and means for applying a draft to said yarns substantially immediately after the yarns pass through said acute angle. Positioned substantially immediately after said drafting means are means for intermittently tensing and relaxing said yarns a plurality of times whereby individual filaments disengage from adjacent filaments and the filaments of one yarn blend with the filaments of adjacent yarns to form a web of continuous filaments.

The amount of draft applied to the yarns may vary from about 2 percent to 10 percent and preferably ranges from about 3 percent to 6 percent. These drafts place the yarns under sufficient tension so that when properly combined with passing'the yarns through an acute angle the yarns will curl. The draft is actually the difierence in lineal speed between two positions through which the yarn passes with the lineal speed of the second position being 2 percent to 10 percent faster than the lineal speed of the first. The amount of tension applied to the yarn will vary dependent upon the amount of elongation the filaments have. In any event, the maximum amount of tension applied should not be greater than 60 percent of the breaking strength of the yarn. Generally the lower the percent elongation of the yarn the lower the amount of tension required, e.g., with rayon yarns having 14 percent elongation tensions as low as 4 percent of the yarn breaking strength will suffice to curl the yarns. Yarns having 18 to 25 percent elongation require tensions of from about 10 to 15 percent of the yarn breaking strength in order to produce a curl in the yarn. The optimum tension for most yarns is from about 25 percent to 35 percent of the breaking strength of the yarn.

The invention will be more fully understood from the description which follows taken in conjunction with the accompanying drawings in which:

FIG. 1 is a schematic top view of apparatus for carrying the present invention into practice;

FIG. 2 is a schematic side view of the apparatus of FIG. 1;

FIG. 3 is a schematic top view of another form of apparatus for carrying the present invention into practice;

FIG. 4 is a schematic side view of the apparatus of FIG. 3;

FIG. 5 is a schematic top view of still other apparatus for carrying the present invention into practice;

FIG. 6 is a schematic side view of the apparatus of FIG. 5;

FIG. 7 is an enlarged cross-sectional view of the curling or crimping apparatus as depicted in FIGS. l and 2;

FIG. 8 is an enlarged cross-sectional view of the curling and crimping apparatus depicted in FIGS. 3 and 4;

FIG. 9 is an enlarged cross-sectional view of the tensing and relaxing apparatus depicted in FIGS. 2 and 6.

Referring to the drawings in FIGS. 1 and 2 there is shown a bank 20 of yarn packages 21. The yarn is continuous multifilament yarn preferably with zero twist or low twist. The yarns are drawn from the packages through a spacer comb 22 to maintain the yarns in substantially the same horizontal plane and approximately equally spaced apart. The spaced yarns are passed between the nip formed by a pair of rotating rolls 23 and 24. The rolls are mounted in suitable stands 25 and 26- and are mounted for rotation in these stands by standard bearings, etc. The sheet of yarns then passes between the nip of a rotatable roll 27 and a stationary blade 28. The blade is in contact with the roll over the entire length of the roll, that is on a line parallel to the roll axis. The roll and blade are suitably mounted in framing 29. The yarns pass to a second pair of rotatable rolls 30 and 31 mounted for rotation in suitable framing 32. The speed of these rolls 30 and 31 is greater than the speed of the rotatable roll 27. The yarn then passes between the nip formed by a fluted roll 33 and a rotatable roll 34. Both the fluted and rotatable rolls are mounted for rotation in suitable framing 35. The fluted roll intermittently passes the yarn when the raised portion of the roll is in line with the surface of the rotatable roll and allows the yarn to relax in the recessed areas. The web is then placed on a conveyor 36 for bonding in further processmg.

In operation as the yarn passes about the edge of the stationary blade it is placed under considerable tension by the pair of nip rolls 30 and 31 and when this yarn passes through these nip rolls and this tension is relaxed intermittently the yarn curls and the intermittent tensing and relaxing of the yarn causes the curl in adjacent individual filaments of a multifilament yarn to disengage and get out of registry and merge into filaments of adjacent yarns to form a web or sheet of individual continuous filaments which are uniformly intermingled throughout the sheet.

Referring to FIGS. 3 and 4 there is shown a bank 40 of packages 41 containing multifilament, zero twist yarns 42. The yarns are fed through a spacer 43 to form a sheet of parallel multifilament yarns. This sheet is passed between a pair of nip rolls 44 and 45 mounted for rotation in suitable framing 46. The sheet passes over a stationary nip blade 47 also mounted in this framing 46 and through a second set of nip rolls 48 and 49 mounted for rotation in the framing 46. The second set of nip rolls is rotating faster than the first set of niprolls. The sheet passes to a third set of hip rolls 50 and 51 running just slightly slower than the speed of the second set of nip rolls. As it passes between these two sets of nip rolls it is intermittently contacted with a beater mechanism 52. The beater mechanism comprises a rotatable roll 53 mounted for rotation in suitable framing 54 and extending outwardly from this rotatable roll are 4 bars 55. These bars are mounted on rods 56 extending outwardly from the center roll 53. The beater mechanism intermittently tenses and relaxes the filaments as they move from the nip of rolls 48 and 49 to the nip of rolls 50 and 51. Rolls 50 and 51 should have a slightly faster peripheral linear speed than rolls 48 and 49 to prevent slack from building up in yarns as they are being conveyed.

This beater mechanism causes the curled filaments to disengage from adjacent curled filaments and become entangled with the filaments of adjacent yarns to form a continuous sheet of interengaged filaments which is placed on a conveyor 57 for further processing.

Referring to FIGS. 5 and 6 there is shown yet another apparatus for carrying the present invention into practice. A bank 60 of packages 61 of zero twist, continuous multifilament yarns 62 is shown. The yarns are drawn from the package through a spacer comb 63 to form a sheet of substantially equally spaced continuous multifilament yarns. This sheet is passed about a portion of the periphery of the nip roll 64 around the sharp edge of the blade 65 and between this blade and a second roll 66. The rolls 64 and 66 rotate in the same direction and are mounted for rotation in bearings mounted in the frame 67. Roll 66 rotates slightly faster than roll 64. The blade 65 is also mounted in the frame 67. A smaller roll 68 also mounted for rotation in bearings in the frame maintains the yarns in contact with the surface of the roll 64 to provide a uniform feed to the blade. The filaments continue in their path to a pair of nip rolls 69 and 70 mounted for rotation in bearings mounted in suit able framing 71. This set of nip rolls is rotating faster than the roll 66. The sheet of filaments then passes between a fluted roll 72 and smooth surfaced roll 73. These rolls 72 and 73 are mounted for rotation in bearings mounted in suitable framing 74. The fluted roll alternately tenses and relaxes the sheet of filaments and causes individual filaments of the yarn to disengage with adjacent filaments to form a web of continuous interengaged filaments. The web is placed on conveyor 75 for further processing.

Referring to FIG. 7 there is shown one type of curling mechanism of the apparatus of the present invention. In tangential contact along a line parallel to the axis of a rotatable roll is a stationary blade 81. This blade is mounted in a suitable spring mounting means 82 so that it may be forced with some pressure against the surface of the roll. The roll is preferably a medium rubber having a Durometer of from about 50 to 75. Mounted a short distance forwardly of the blade is a pair of rotatable nip rolls 83 and 84. These rotatable nip rolls rotate slightly faster than the first roll. The sheet of yarns pass between the roll and the blade and about the edge of the blade to the nip of the rotating rolls. By this technique the yarns are curled or crimped. The draft between nips A and B shown must be greater than 2 percent and the angle on at which the yarn passes about the blade must be less than 70 degrees. It is desirable that there be a finite distance C between the nip formed by the blade and the first roll and the edge of the blade. The reason for this is that if the blade edge is on the resilient surface of the roll it will tend to become indented in the surface and cause filament breakage. Distances of from about Ms inch to A inch have been found satisfactory in curling polyester and rayon yarns.

Referring to FIG. 8 there is shown another curling apparatus comprising a first set of nip rolls and 91 rotating in the direction of the arrows shown and a second set of nip rolls 92 and '93 rotating slightly faster than the first set and rotating in the direction of the arrows shown. Mounted between the two sets of nip rolls is a stationary blade 94. The blade is mounted out of alignment of the two nips D and E. A sheet of continuous filament yarns is passed between the first nip up and over the blade into the second nip. This arrangement has been found satisfactory for crimping polyester and rayon yarns. The second set of nip rolls must have a surface linear speed of at least 2 percent greater than the surface linear speed of the first set of nip rolls. The distance F that the blade must be from a line between the two nips may range from about Ms inch to a couple of inches or even greater. The important thing is that the angle B at which the yarn passes and goes over the blade must be 70 degrees or less. In operation the important points on the curling of the yarn are that the yarn must pass through a path that is at an acute angle to itself of 70 degrees or less and the yarn either as it passes through this angle or immediately after passing through this angle must be under tension and have at least 2 percent draft. With these two criteria the mechanism will curl or crimp polyester, polyamide, acrylic, rayon, or other synthetic polymer or artificial multifilament yarns.

The blades described in accordance with the present invention may be of various rigid or semi-rigid materials such as steel, preferably spring steel or other various plastic materials. Blades having a thickness of .020 inch have been found suitable for use in accordance with the present invention. The edge of the'blade may be straight or it may be beveled on either or both sides.

Another modification of the apparatus is to heat the yarn as it is passing about the blade to aid in the curling operation. The amount of heat will, of course, depend upon the type of yarn being treated. Such temperatures may vary from about room temperature to about 430 F. The temperature should not be so high as to overly soften the yarn as it is being treated. The heating of polyester yarns improves the curling operation and tends to set the curl in the yarn. The heating of rayon yarns reduces the moisture content of the yarn and the humidity around the yarn to give better curling.

After being curled the yarns are intermittently tensed and relaxed. Referring to FIG. 9 there is shown a simple mechanism for tensing and relaxing the yarns. This mechanism comprises a pair of rolls. These rolls are rotatable in the direction of the arrows shown. The upper roll 100 has flutes 101 over its entire surface so that as a high area 102 contacts the bottom roll 103 the yarns passing between the rolls are moved forwardly whereas when a recessed area aligns with the axis of the bottom roll the yarns are allowed to relax. This action of the mechanism alternately tenses and relaxes the curled multifilament yarns a plurality of times which forces the individual filaments of the yarn to disengage with adjacent filaments of that same yarn and merge with adjacent individual filaments of adjacent yarns into a web of interengaged continuous filaments. The fluted rolls should have a peripheral linear speed such as to prevent slack from building up as the sheet of filaments is being processed.

Another mechanism for applying this alternate tensing and relaxing of the yarns has been previously described in conjunction with FIGS. 3 and 4. Furthermore, if desired, more than one mechanism for tensing and relaxing the yarns may be put in series to further separate individual filaments from each other and merge them into a helter-skelter pattern or web of filaments.

Multifilament yarns used in accordance with the present invention may be of any of the various synthetic filaments such as rayon, the polyamides, the polyesters, the polyolefins, etc. The denier of the individual filaments may vary from about 2 denier up to 20 denier or higher and the yarns may contain anywhere from about 10 to 200 filaments or more.

Although all of the various holders. pulleys, belts, beaters, or like mechanical means including suitable framing have not been illustrated completely in the drawings or described in the specification for driving or supporting the various rotating cylinders, roll, beaters, at their desired or required speeds or with the rotation or movement indicated by the direct arrows it is to be appreciated that such elements have been omitted to keep the drawings and descriptions distinct and to avoid the introduction of matters which are well known expedients in the art. The mechanical driving means and various frames which are used are conventional and merely involve the application of well known mechanical principles.

The invention will be further illustrated in greater detail by the following specific examples.

6 EXAMPLE I Twenty four mutifilament, zero twist rayon yarns are placed in a parallel, horizontal plane with the yarns approximately inch apart. The yarns used are 600 total denier per yarn and 4 denier per filament. The parallel plane of twenty-four yarns is passed through the apparatus depicted in FIGS. 1 and 2. The yarns are taken from suitable packages drawn through a spacer comb to form the plane of the yarns, which is fed through the first set of nip rolls. The yarn is then passed through the single stationary roll and blade unit, and from there to the second set of nip rolls. The second set of nip rolls rotates 5 percent faster than the roll in contact with the stationary blade. The angle that the yarn makes with the blade as it passes about the blade is approximately 30 degrees. The single roll has a rubber surface (Durometer 65). The blade is spring steel and has a thickness of .020 inch. The parallel multifilament yarns after passing through the blade and roll and to the second set of nip rolls is substantially uniformly curled. The yarns pass from the second set of nip rolls to the nip formed by a fluted roll and a smooth surface roll and are intermittently relaxed and tensed a plurality of times to merge individual filaments to a uniform web of individual continuous filaments arranged in a general helter-skelter pattern but aligned in the length of the web so formed.

EXAMPLE II Twenty-seven multifilament, zero twist rayon yarns are placed in a parallel horizontal plane with the yarns approximately Ainch apart. The yarns used are total denier per yarn and 3.6 denier per filament. The parallel plane of the twenty-seven yarns is passed to the apparatus depicted in FIGS. 3 and 4. The yarns are taken from suitable packages and drawn through a spacer comb to form the plane of yarns and fed to the curling mechanism. The curling mechanism comprises a first set of nip rolls and a second set of nip rolls with a stationary blade placed therebetween but out ofthe line between the two nips. The yarns pass through the first set of nip rolls about the blade and through the second set of nip rolls. The second set of nip rolls rotate at approximately 3 percent faster than the first set of rolls. The blade is spring steel and has a thickness of .020 inch. The distance between the line between the nips at the top of the blade is approximately one inch. The angle which the yarn makes as it passes about the blade is approximately 60 degrees. The parallel multifilament yarns after passing through the second pair of nip rolls are substantially uniformly curled. The yarns then pass through another set of nip rolls. Between the second and third pair of nip rolls there is a beater roll as shown in the drawings. As the beater roll rotates the filaments are alternately stretched and relaxed. This action separates and individualizes the filaments and merges them into a uniform web of continuous filaments.

EXAMPLE HI Twenty-four multifilament, zero twist polyester yarns are placed in a parallel, horizontal plane with the yarns approximately inch apart. The yarns used are 670 total denier per yarn, 13 denier per filament. The parallel plane of 24 yarns is passed to the apparatus depicted in FIGS. 5 and 6. The yarns are taken from suitable packages and drawn through a spacer comb to form the plane of yarns which is fed to the double roll and blade unit. A uniform tension is placed on the yarns as they are fed to the blade unit. The uniform tension is provided by the small roll in contact with the input roll. The input roll is a steel roll having a sandblasted surface. The second roll has a rubber covered surface with the rubber having a Durometer hardness of approximately 50. The blade is spring steel and has a thickness 7 of .020 inch and a beveled edge. The beveled edge contacts the surface of the steel roll and the other edge contacts the rubber roll. The yarns are drafted about 3 percent as they .pass through the mechanism. The parallel multifilament yarns after passing through the blade and pair of rolls are substantially uniformly curled and passed through a pair of nip rolls under a minimum of tension. The minimal tension is sufficient to prevent sagging of the curled yarns. From this pair of nip rolls the yarns are passed to a third pair of nip rolls consisting of a rubber roll and a steel roll. The rubber roll has flutes on its surface. These rolls intermittently tense and relax the filaments which separates the filaments and merges them into a uniform web. A uniform web weighing approximately 150 grains per square yard and comprising individual continuous filament yarns in a helterskelter :pattern is formed.

Although several specific examples of the inventive concept have been described for purposes of illustration, the invention should not be construed as limited thereby nor to the specific features mentioned therein. It is understood that changes, modifications, variations, may be made in the method and apparatus as herein described without departing from the spirit and scope of the invention.

What is claimed is:

1. A method of producing a web of individual filaments arranged in an overlapping, interengaging, intersecting layer of individual continuous filaments comprising, continually moving a plurality of continuous filament, zero twist yarns arranged in a plane in a first path and at a first speed, changing the direction at which the said yarns are moving to a second path making an angle of less than 70 degrees with the direction of said first path by directiing the yarns over a member while simultaneously increasing the speed at which the yarns are moving at least 2 percent of the first speed to apply tension to said yarns, whereby stresses are placed in the yarn to impart a tendency in the yarn to curl, removing said tension whereby a series of curls are formed in the yarns and applying intermittent tensing and relaxing forces to the yarns whereby the curls of the individual filaments are placed out of registry and the individual filaments merge into a uniform web of continuous filaments.

2. A method according to claim 1 wherein the speed is increased from about 2 percent to percent of the first speed.

3. A method according to claim 1 wherein the speed is increased from about 3 percent to 6 percent of the first speed.

4. Apparatus for producing a web of interengaged, continuous filaments, comprising, supply means for supplying a plurality of continuous multifilament, zero twist yarns, spacing means for arranging the yarns in a plane of substantially parallel, spaced apart multifilament yarns, means including a member over which the yarns are passed for moving the yarns in an angular direction of less than 70 degrees, means for increasing the speed of the yarns at least 2 percent while moving in said angular direction to apply tension to said yarns, whereby stresses are placed in the yarn to impart a tendency in the yarns to curl and means for removing said tension and applying intermittent tensioning forces to the plurality of yarns whereby a curl is placed in the yarns when the tension is removed and individual filaments in each yarn are disengaged with adjacent filaments and merge with fllaments or adjacent yarns when the intermittent tensioning forces are applied to produce a web of filaments.

5. Apparatus according to claim 4 wherein the means for moving the plane of yarns in an angular direction and increasing the speed of the yarns comprises, a first rotatable roll, a stationary blade constituting the memher in line contact with the surface of the first rotatable roll to form a nip therebetween through which the plane 8 of yarns is passed and a pair of nip rolls rotating at a faster peripheral linear speed than said first rotatable roll and spaced from said first roll and blade and in a lower horizontal plane than said first roll and blade.

6. Apparatus according to claim 4 wherein the means for moving the plane of yarns in an angular direction and increasing the speed of the yarns comprises, two pair of rotatable nip rolls, means for rotating the second pair of nip rolls at a faster peripheral linear speed than first pair, said pairs of nip rolls being in the same horizontal plane and a stationary blade constituting the member positioned between said pairs of nip rolls but above such horizontal plane whereby the yarns pass from the first set of nip rolls upwardly about the edge of the blade and down into the second set of nip rolls.

7. Apparatus according to claim 4 wherein the apparatus for moving the plane of yarns in an angular direction and increasing the speed of the yarns comprises, a pair of rotatable rolls, the axis of said rolls being parallel and the rolls positioned with respect to each other to form a nip between the rolls and having a minimum clearance between the rolls at the nip, means for rotating the rolls in the same direction and at different linear surface speeds, a blade constituting the member positioned adjacent the nip and extending parallel to the axis of said rolls, said blade being in contact with the surface of both of said rolls.

8. Apparatus according to claim 4 wherein the means for removing the tension and applying intermittent tensioning forces to place a curl in the stressed yarns comprises, a pair of nip rolls spaced from the means for increasing the speed of the yarns and in the same horizontal plane, a beater roll comprising a rotating member and at least two bars attached to said member parallel to the axis of the said rotating member and spaced therefrom, said rotating member being positioned so that the bars move through the path in which said plurality of yarns are passing whereby the yarns are intermittently tensioned and relaxed to place a curl in the filaments of the yarns and deregister the curl in the filaments of each yarn and merge filaments with adjacent filaments of adjacent yarns.

9. Apparatus according to claim 4 wherein the means for removing the tension and applying intermittent tensioning forces to place a curl in the stressed yarn comprises, a pair of nip rolls one of said rolls having flutes on its surface parallel to the axis of the roll and the other of said rolls having a smooth surface whereby yarns passing through the nip of said pair of rolls are intermittently tensioned and relaxed to place a curl in the filaments of the yarns and deregister the curl in the filaments of each yarn and merge filaments with adjacent filaments of adjacent yarns.

10. Apparatus for producing a Web of interengaged, continuous filaments comprising, supply means for supplying a plurality of continuous multifilament, zero twist yarns, spacing means for arranging the yarns in a plane of substantially parallel, spaced apart multifilament yarns, a rotatable roll and a stationary blade in tangential contact with the surface of said rotatable roll along a line parallel to the axis of said roll to form a nip therebetween, said rotatable roll and blade positioned to accept the plane of parallel yarns from said spacing means, a first pair of rotatable nip rolls positioned forwardly of and beneath the nip formed by said rotatable roll and blade to change the direction in which the yarns are moving, means for rotating said first pair of rotatable nip rolls at a faster peripheral linear speed than the peripheral linear speed of said rotatable roll to apply tension to the yarns as they change direction and a second pair of rotatable nip rolls positioned to accept the plane of yarns from said first pair of rotatable nip rolls, one of said rolls of said second pair having flutes on its surface parallel to the axis of the roll and the other roll of said second pair having a smooth surface to remove the ten sion and form curls in the yarns and to intermittently tension the curled yarns to disengage adjacent filaments and merge them with filaments of adjacent yarns to form a web.

11. Apparatus for producing a web of interengaged continuous filaments comprising, supply means for supplying a plurality of continuous multifilament, zero twist yarns, spaced means for arranging said yarns in a plane of substantially parallel spaced apart multifilament yarns, a first set of rotatable nip rolls, a second set of rotatable nip rolls, the nips of said first and second set being in the same horizontal plane, a stationary blade positioned between said first and second sets and having a free edge extending above said horizontal plane whereby the yarns change direction as they pass from said first set of rolls over the blade to said second set of rolls, means for rotating said second set of nip rolls at a faster peripheral linear speed than the peripheral linear speed of said first set to apply tension to the yarns as they pass over said blade, and a third set of rotatable nip rolls positioned to accept yarns from said second set of rotatable nip rolls, one of said rolls of said third set having flutes on its surface parallel to the axis of said roll and the other roll of said third set having a smooth surface, to remove the tension and form curls in the yarns and to intermittently tension the curled yarns to disengage adjacent filaments and merge them with filaments of adjacent yarns to form a web.

References Cited UNITED STATES PATENTS 2,022,854 12/ 1935 Greenwood. 2,115,313 4/1938 Matthew et a1. 2,215,112 9/1940' Van Beck et al. 2,244,203 6/ 1941 Kern. 2,247,504 7/1941 Kern. 2,790,208 4/1957 Smith. 3,017,309 1/1962 Crawford et a1. 3,175,348 3/1965 Block 281.5 XR 3,340,576 9/1967 Pannill et al. 3,376,609 4/ 1968 Kalwaites. 3,392,425 7/ 1968 Kalwaites.

ROBERT R. MACKEY, Primary Examiner US. Cl. X.R.

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