US3230584A

US3230584A - Methods and apparatus for making strands, rovings, yarns and the like

Info

Publication number: US3230584A
Application number: US350146A
Authority: US
Inventors: Kalwaites Frank
Original assignee: Johnson and Johnson
Current assignee: Johnson and Johnson
Priority date: 1964-03-05
Filing date: 1964-03-05
Publication date: 1966-01-25
Anticipated expiration: 1983-01-25

Description

Jan. 25, 1966 F. KALWAITES 3,230,584

METHODS AND APPARATUS FOR MAKING STRANDS, ROVINGS, YARNS AND THE LIKE Filed March 5, 1964 4 SheetsSheet 1 INVENTOR Fem/K haw/r55 ATTORNEY Jan. 25, 1966 F. KALWAITES 3,230,534

METHODS AND APPARATUS FOR MAKING STRANDS, ROVINGS, YARNS AND THE LIKE 4 Sheets-Sheet 2 Filed March 5. 1964 INVENTOR Aka K 4741/;44/755 BY MM 7 M ATTORNEY Jan. 25, 1966 F. KALWAITES METHODS AND APPARATUS FOR MAKING STRANDS, ROVINGS, YARNS AND THE LIKE 4 Sheets-Sheet 5 Filed March 5, 1964 ATTORNEY Jan. 25, 1966 F. KALWAlTES TUS FOR MAKING STRANDS 3,230,584 ROVINGS, YARNS METHODS AND APPARA AND THE LIKE 4 Sheets-Sheet 4 Filed March 5, 1964 INVENTOR /?4/VA [41/144/755 [2,121. BY

fl nmm M4.

ATTORNEY United States Patent 3,230,584 METHODS AND APPARATUS FOR MAKING STRANDS, .ROVIN GS, YARNS AND THE LIKE Frank Kalwaites, Somerville, N.J., assignor to Johnson & Johnson, a corporation of New Jersey Filed Mar. 5, 1964, Ser. No. 350,146 26 Claims, (Cl. 19-150) The present application is a continuation-in-part of my co-pending application Serial No. 772,740, filed November 10, 1958, and now abandoned.

This invention relates to strands, rovings, yarns and the like and to novel methods and apparatus for making the same.

In the conventional production of presently available commercial yarn, textile fibersare carded into a fibrous web which is drafted, made into rovings, or otherwise mechanically processed in a plurality of separate steps, and then twisted or spun into yarn having sufficient strength and integrity to be used in weaving, knitting, braiding, and like textile fabricating operations. The resulting twisted yarn ordinarily exhibits an undesirably irregular and vvariable linear density, wherein thin, uneven and weak sections andthick, bulky portions are commonplace. Additionally, this twisted yarn is a compromise of many, antagonistic qualities, notably softness and strength, which are, usually inversely related. In some cases, this compromise of qualities severely limits the usefulness of the twisted yarn, such as for example, when softness is desirable but must be sacrificed for strength, or vice versa.

In co-pending, commonly-assigned patent applications Serial Numbers 745,010 and 745,163, filed June 27, 1958, now US. Patents No. 3,135,023 and No, 3,018,521, respectively, there are disclosed methods and apparatus for making strands, yarns and the like involving, inter alia, the application of fluid rearranging forces, including a combination of liquid and pneumatic forces, to a layer of a fibrous starting material whereby it is divided and formed into strands having substantially, constant linear density, along with excellent softness and good strength. Such methods and apparatus have commercial practicability, and acceptable strand s, yarns, and the like, have been made employing the principles set forth in said patent applications. l

, It has now been discovered that the fibrous layer of starting material may be converted into a plurality of unitary strands by methods and apparatus employing pneumatic principles exclusively. Such methods and apparatus involve the passing of a gaseous medium, such as air, through the fibrous layer of starting material and during such passage dividing the layer into a plurality of fibrous strips.

Portions of the gaseous medium arelaterally deflected in spaced, generally parallel zones so that they exert components of force on each of the fibrous strips in directions generally parallel to the plane thereof, whereby at least one of the sides of each of thefibrous strips is individually rolled inwardly in substantially spirallywrapped fashion to form' unitary strands.

It has also been discovered that the conversion of the fibrous layer of starting material into a plurality of unitary strands is facilitated by drafting the starting fibrous layer or otherwise increasing its degree of fiber alignment with respect to the longitudinal axis of the fibrous layer. This is accomplished, according to another .phase of the present inventive concept, by forming a fibrous layer on a moving surface, such as the peripheral surface of a rotating dolfing cylinder of acard, and then removing the fibers therefrom and depositing them in pressing contact 3,230,584 Patented J an. 25, 1966 Ice on another moving surface, such as an endless supporting screen or belt, which possesses a greater surface linear speed than the surface from which the fibers are removed. In this way, the fibers are not only doifed from the forming surface and transferred to a supporting carrier but are simultaneously drafted, whereby higher degrees of fiber parallelization and alignment are provided to facilitate the strand formation. F

The starting web or layer which is processed to form the products of this invention may contain-natural or synthetic, vegetable, animal or mineral fibers such as cotton, silk, wool, vicuna, mohair, alpaca, flax, ramie, jute, abaca, etc.; synthetic or man-made fibers such as the cellulosic fibers, notably cuprammonium, viscose or regenerated cellulose fibers; cross-linked cellulosic fibers such as Corval and Topel; cellulose ester fibers such as cellulose acetate (Celanese) and cellulose tri acetate (Arnel); the saponified cellulose ester fibers such as Fortisan and Fortisan-36; the polyamide fibers suchas nylon 420, nylon 6 (polycaprolactam), nylon 66 (hexamethylene diamine-adipic acid), nylon 610 (hexamethylene diamine-sebacic acid), nylon 11 (l'l-amino'undecanoic 'acid-Rilsan);' protein fibers such as Vicar-a;

halogenated hydrocarbon fibers such as Teflon (polytetrafluoroethylene); hydrocarbon fibers such as poly: ethylene, polypropylene, polybutadiene, and polyisobutyl ene; polyester fibers such as Kode'l and Dacfo'n; vinyl fibers such as Vinyon and saran; dinitrile fibers such as Darvan; nitrile fibers such as Zefran; acrylicfibers such as Dynel', Verel, Orlon, Acril-an, Creslan, etc.; mineral fibers such as glass, metal; etc.

The starting web may comprise either discontinuous fibers or continuous fibers, i.e. filamentary material. i If discontinuous fibers are used in'the starting web the lengths of the fibers will vary from about /2 inch up to about 2 /2 inches or more in length, depending upon the particular properties and characteristics requiredor desired in the resulting strands. If desired, the fibrous layer may contain a minor proportion, less than about by weight and preferably less than about 25% by weight, of fibers other than those of textile length. These other fibers may be of papermaking length, which extend from about /2 inch inlength down to about of an inch in length, which shorter fibers normally cannot be used in conventional methods of producing strands or yarns.

7 less than about inch and down to about of an inch.

If continuous fibers are used in the starting web, e.g., a web of spread tow, .any of the synthetic or made-made continuous filaments may be used, or any of the longer natural fibers, e.g., wool, vicu'na, etc., which veryoften have lengths greater than 2 /2 inches may be used; The continuous fiber webs used in accordance with the present invention have a high degree of orientation and there is little cross entanglement of the fibers.

The denier of the individual synthetic fibers, whether discontinuous or continuous, referred to above is pref-v erably in the range of'the approximate thickness of the natural fibers mentioned and consequently deniers in the range of from about 1 to about 5 are preferred. Where greater opacity or greater covering power is desired, special fiber deniers of down to about /1 or even about /2 may be employed. Where desired, denier-s of up to about 5.5, 6, 8, 10, 15, or higher, may be used. The minimum and maximum denier used are naturally dicrated by the desires or requirements for producing a par- 3 ticular strand or yarn, by the machines and methods for producing the same, and so forth.

The weight of the fibrous web or layer of starting material may be varied within relatively wide limits de-,

pending upon the requirements of the intermediate or the completed products. A single, thin web of fibers, such as produced by a card, .as presented by the dofiing cylinder, may have a weight of from about 25 to about 250 or more grains per square yard and may be used in the application of the principles of the present invention.

Furthermore, a single thin web of continuous filaments, such as produced by spreading a tow of continuous filaments into a wide sheet by using fluid forces to spread the tow, may have a weight of from about 40 to about 200 or more grains per square yard and may be used in the application of the principles of the present invention. Within the more commercial aspects of the present invention, however, web Weights of from about 50 grains per square yard to about 150 grains per square yard are contemplated.

It, of course, will be appreciated that the heavier the starting web is, the heavier will be the individual strands produced therefrom, assuming no change in the number of strands so produced. And, similarly, the greater the number of strands produced from a starting web, the lower will be the weight of each individual strand so produced.

As will become evident from a consideration of the following specification, when the fibrous starting material is divided by the gaseous medium into a plurality of fibrous strips which, in turn, are rolled into unitary strands, the number and width of the fibrous strips are determined principally by the nature, arrangement and orientation of the fibers in the starting layer, the freedom of movement of the individual fibers as they are moved on'a supporting member, the physical nature and intensity of the gaseous medium employed, the shape, size, and the spacing of the parallel zones in which the pneumatic forces are applied by the gaseous medium, and the like.

The number and width of the fibrous strips which are converted into unitary strands affects the length of the individual fibers that may be employed in the starting material as well as the degree of fiber alignment that should be present'in the starting material in order to avoid too many interconnecting cross fibers and to achieve substantially separate strands as'the final prodnote. If the individual fibers in the starting material are no longer than the distance separating the strands produced, the degree of alignment or parallelization of the fibers in the starting material is relatively unimportant. However, when the individual fiber length is greater than the distance between the strands produced, the degree of alignment of the fibers in the starting material becomes increasingly important as the length of the fibers increases. If it is desired to achieve substantial separation of adjacent strands without being required to sever any large number of interconnecting fibers, the degree of alignment or parallelization of the starting fi'bers must be higher when the fibers are longer.

A conventional card web as present on the dofi'ing cylinder of the card makes a suitable starting material for the application of this invention, particularly after it has been given some additional drafting or aligning over that produced by the carding machine. In such fibrous webs, it is diificult to measure fiber orientation or alignment directly because the individual fibers thereof are curled, hooked and bent, with various segments of the fibers extending in various directions. A kind of average orientation which is helpful in describing the physical characteristics of the web may be defined and experimentally measured. This physical characteristic is called the degree of fiber orientation, the degree of fiber alignment, or the percent of fiber parallelism. This dee or percent is determined by lightly bonding the web uniformly with a material such as starch, drying the bonded web, measuring tensile strengths lengthwise and crosswise of the bonded web and then computing the percentage of lengthwise or length-strength of the web to its total strength. Total strength, for this purpose, is the arithmetical sum of the tensile strengths in the long and cross directions. Thus, if the long tensile strength in a conventional card web is 3 times the cross tensile strength, the degree of fiber orientation is 75%.

One skilled in the art who applies the teaching of this specification, will be able to examine a given starting fibrous layer and determine whether the principles of this invention can be used to produce satisfactory strands connected by a minimum, if any, connecting fibers. In' making this determination, measurement of the degree of fiber orientation as defined above will be helpful.

When the fibers of the starting material are continuous there must be little if any cross-over of the continuous fibers and virtually all of the continuous fibers must be substantially parallel to each other and run in'the longitudinal direction of the starting web. When the fibers of the starting material are of fairly long textile length, say, about 1% inches or over, the starting fibers should display an alignment of at least about 90% or more in the longitudinal direction prior to the initiation of strand formation. With fibers of medium textile length, say, from about inch to about 1% inches, a fibrous starting material having about or more alignment will produce satisfactory strand products. If fibers of relatively short textile length, from about /2' inch to about /1 inch, are employed, a strating material of as low as about 70% may be used.

The, invention will be more fully understood from the description which follows, taken in conjunction with the accompanying drawings in which there are illustrated preferred designs of machine and modes of operation embodying the invention. It is to be understood that the invention is not to be considered limited to the constructions disclosed except as determined by the scope of the appended claims. In the following drawings:

FIGURE 1 is a simplified, fragmentary, schematic per spective view showing the general principles of operation of the present invention;

FIG. 2 is a simplified, schematic cross-sectional view showing in greater detail the construction of a vacuum box employed with this invention;

FIG. 3 is a simplified, schematic, fragmentary, ex-

. ploded perspective view of a part of the front end of the same vacuum box;

FIG. 4 is a simplified, schematic view in plan of the vacuum box and its associated deflector forming plates and cooperating forming slots with the fibrous web and strands-omitted for purposes'of clarity;

FIG. 5 is a simplified, schematic view in cross section, taken on the line 55 of FIG. 4, looking in the direction indicated, prior to the formation of the strands;

FIG. 6 is a simplified, schematic view in cross section, taken on the line 6-6 of FIG. 4, looking in the direction indicated, showing the initial formation of the strand;

FIG. 7 is a simplified schematic view in cross section, taken on the line 77 of FIG. 4, looking in the direction indicated, showing the formation-of the strand at a later stage than that shown in FIG. 6;

FIG. 8 is a simplified, schematic view in cross section, taken on the line 8-8 of FIG. 4, looking in the direction. indicated, showing the strand in substantially completed orm;

' FIG. 9 is a simplified, schematic, fragmentary view in, plan of a modification of the deflector forming plates and cooperating forming slots in the vacuum box;

FIG; 10 is a simplified, schematic view in cross section, taken on the line 10 -10 of FIG. 9, looking in the direc-- tion indicated, showing an initial stage of the formation of the strand;

FIG. 11 is a simplified, schematic view in cross section, takenon the line 1111 of FIG. 9, looking in the direction indicated, showing an intermediate stage of formation of the strand;

FIG. 12 is a simplified, schematic view in cross section, taken on the line 12,12. of FIG. 9, looking in the direc tion indicated, showing the strand in substantiallyv completed form;

FIG. 13 is a fragmentary perspective view in slightly exploded form, showing a strand product of the present invention; and

FIG. 14 is a fragmentary perspective view in slightly exploded form, showing another embodiment of the strand product of the present invention.

In the embodiment of the invention illustrated in FIGS. 1 to 81 of the drawings, aconventional textile card comprisinga main cylinder 20 and a conventional dofling roll or cylinder 22 are shown in FIGS. 1. and 2 to provide for the normal carding of the fibers fed to the card and the producing of a thin, fibrous web on the dofiing cylinder. The directions of rotation of the card and the doffing cylinder are as illustrated by the directional arrows. Only a portion of the width of the main cylinder 20 and dofting cylinder, 22 of the. card is illustrated and it is to be ap preciated, that the actual width ofthe main cylinder and doffing cylinder is manytimes the width illustrated.

Immediately adjacent. the dofiing cylinder 22 and approximately at the position where the fibrous web formed thereon is conventionally removed by the usual textile dofling means is a suction or vacuum box 24. A hollow conduit or vacuum header 28, connected to asuitable suction device (not shown), passes through the interior of the vacuum box 24.and'provides the me'ans for withdrawing airfrom within the vacum box 24, as well as constituting a supporting bracket therefor. The hollow vacuum header 28 is adjustably mounted in supporting brackets so that the nose portion 32 (best seen in FIG. 3) of the vacuum box can be accurately positioned and spaced with respect to, theperiphery of the rotating dofier cylinder 22 Such positioning and spacing is important to the application of the present invention and is in the range of from about 0.005 inch to about 0.125 inch and preferably from about 0.015 inch to about 0.030 inch.

As seen in FIG. 3, the sides of the vacuum box'24 are extended forwardly above and beyond the nose portion .32 thereof to form

end flanges

34, 34 in which elongated

slots

36, 36 are provided to permit-the adjustable and accuratemounting of a guide nip roller 36 therein. Suitable locking means (not shown) are provided for mounting and securing the guide nip roller 36 in position properly adjusted with respect to the periphery of the doffing cylinder 22. The guide-nip roller 36 is positioned as close as conveniently possible to the doffing cylinder 22 so as to provide a minimum of clearance and to facilitate the trans fer of a fibrous web from the dofling cylinder. This clearance will depend to some extent upon the weight of the web on thedofling cylinder, the nature and staple length of the fibers in the fibrous web, etc., and in most cases, a clearance of from about 0.005 inch to about 0.125 inch, and preferably from about 0.015 inch to about 0.030 inch has been found satisfactory. This distance, however, may be increased in particular situations where the web weight or type of fiber permit such an increase.

, A foraminous supporting screen or carrier 60, such asa nylon or wire belt, is positioned so as to cover the nose portion 32 of the vacuum box 24, pass under the'guide niproller 36, and then extend along the top surface of the vacuum box 24. This foraminous supporting screen 60 is endless and moves in a complete cycle past the vacuum box 24 and its nose portion 32 for a purpose to become clear. hereinafter.

Consideration of FIG. 2 will reveal that when air is drawn into the vacuum box 24 by the vacuum header 28 there will be suction or a negative pressure applied to the a, doffing cylinder to induce an air flow pastthe guide nip roller 36 and through the foraminous supporting screen 60 into the vacuum box 24. This airflow is basically in two parts with one lowerpart passing between the guide.

nip roller 36- and the nose 32 of the vacuum box 24, and the other upper part of the air flow passing between the guide nip-roller 36 and a supporting guide bracket 30.

The nose portion 32 of the vacuum box 24 is perforated, as illustrated in FIG. 3, to provide for a more even and uniform flow of air whereby the fibers on the dofiing cylinder 22 are. removed therefrom and are drawn in the direction of the vacuum box 24 at that location and are thus deposited, on the foraminous supporting screen 60. Both parts of the air flow referred to above pass through I the foraminous supporting screen- 60 on their way into the vacuum box 24 and in so, doing hold in place the fibers of the fibrous web, which are positioned on the foraminous screen.

The. upper surface of'the vacuum box-24 is open and a removable, slotted forming plate 38. is adapted to be positioned in such a way as to extend over this opening. A locking slot 40 is provided along the full length, of the supporting guide bracket 30; and is adapted to cooperate with a locking lip 42, which extends downwardly along the full length of the removableforming-plate 3.8. The length of the forming plate 38 is sufiicient to extend beyond thev rear edge of the opening in-the-upper surface.

of the vacuum box 24 and to restupon the rear slanted edge thereof.

Forming slots 44 are provided in the top surface of the removable. forming plate-38 of the vacuum boxand provide openings'through which air may be drawn into the vacuum box 24-by means of the vacuum header-28 and associated suction means. As shownin FIGS. land 4, the forming slots 44 extendgenerallyangularly along the length of the. formingplate- 38. but are slanted thereon with respect to the m'achinedirection to such an extentthat' thefopeningat the leading end of one. forming slot at least coincides with and preferably slightly overlaps the opening in the trailing edge-of the adjacent slot, as determined by a line extending in the machine direction.

An air deflector frame or open plate 46 (FIG. 1) comprising a forwardly positioned support 48 and a rearwardly positioned support 50 isprovided and may be positioned directly above the removable forming plate38 and the, foraminous supporting screen 60. Legs 52, 52- are. provided so that the air deflector plate 46 is. accurately and sufficiently spaced from and generally parallel to the removal forming plate 38 and the foraminous supporting screen 60. The

legs

52, 52 of the air deflector frame 46 reston the foraminous supporting screen 60 and are prevented from movement therewith by extension bars (not shown) which extend beyond the sides of .the foraminous supporting screen 60 and are secured to a stationary structure, preferably the card frame itself. Deflector strips 54 are provided and extend from the forward support 48 to the rearward support 50. As illustrated in FIG. 4, the air deflector strips 54 extend generally in the machine direction but arev slanted slightly with respect thereto so that their vertical projections generally fall upon and cover the forming slots 44.

The cross-sectional views'shown in FIGS. 6 through 8 illustrate the relationship of the air deflector strips 54 and the forming slots 44. The air deflector strips 54 are wider and longer than the forming slots 44 and, as positioned, prevent the direct access of air into these slots. Theileft hand edge of each deflector strip 54 (as seen in FIGS. 6-8), is positioned substantially above the left-hand edge of each forming slot 44, whereas the right-hand edge of each deflector strip 54 is positioned well to the right-hand edge of each forming slot 44.

Although the terms right-hand and left-hand are used herein with reference to specific constructions utilizing the present invention, it is to be appreciated that such specific constructions are primarily illustrative and could be readily reversed, in which case left-hand and right-hand descriptive terms would also be reversed.

The positioning of the air deflector strips 54 thus divides the flow of air into the vacuum box into two basic components. The first of these components travels downwardly in substantially a vertical or near-vertical direction beneath the left hand side of the air deflector strips 54, as viewed in FIGS. 6 through 8, and passes through the foraminous supporting screen 60 and then through the forming slots 44. This substantially vertical or nearvertical air flow exerts a force against the layer, one component of such force being generally perpendicular to the plane of the layer. This component tends to hold the parts of the layer in position on the movable foraminous supporting screen 60 which is interposed between the air deflector strips 54 and the slotted forming plate 38 and,

which continuously moves past the forming slots 44.

The second component of the air flow passes to the right of and under the air deflector strips 54 and, as illustrated by the directional arrows, possesses a component of force which is generally horizontal and substantially parallel to the plane of the foraminous supporting screen 60 and the web positioned thereon. This lair flow additionally is concentrated and increased by the fact that the air is being funneled through the narrow opening created between the deflector strip and the foraminous screen. It is this increased air flow which, in passing angularly through the fibrous web, severs it and then, due to its horizontal component of force, rolls it inwardly and in spiral fashion into a untiary strand.

If desired, the air deflector strips may be slanted slightly upwardly, as shown in FIGS. 6 through 8. This angle may range from as low as about to as high as about 30 with respect to the plane of the forming plate and preferably from about to about 20.

It will thus be apparent (FIG. 2) that the fibrous web which is formed on the dofling cylinder 22 is removed from the periphery of such cylinder by the vacuum sucking action at the nose portion 32 of the vacuum box 24. In this action, the fibrous web is deposited upon the foraminous supporting screen or carrier 60 which is interposed between the vacuum box 24 and the dofling cylinder 22. The foraminous supporting screen 60 moves onwardly carrying the fibrous web past the nose portion 32,

left hand side of the air deflector strips, as described previously in connection with FIGS. 4 through 8, and holds that portion of the fibrous web in position. The laterally deflected portion of the air flow penetrates the fibrous web in zones at the right edge of forming slots 44 to divide the web into a plurality of fibrous strips. As the strips move onwardly in a machine direction along the forming plate 38 and under the air deflector strips 54, the horizontal forces exerted by the air flow, in conjunction with the slanting and tapering configuration of these forming slots 44, is such that thesides of the divided fibrous strips are individually rolled inwardly to form a plurality of unitary strands. As is seen, the zone in which the air passes through the fibrous web is progressively shifted to the left in FIGS. 6 through 8 as the fibrous web advances in the machine direction.

The precise operation is illustrated in FIGS. 5 through 8. In FIG. 5, the fibrous Web is illustrated in unitary, intact form, being carried by the foraminous supporting screen 60 as it moves over the forming plate 38 prior to its movement over the forming slots 44.

FIG. 6 illustrates the initial division of the fibrous web into a series of substantially parallel, divided fibrous strips. The position illustrated is subsequent to the initial division of the fibrous web and shows the initial rolling inwardly of one side of each fibrous strip.

FIG. 7 illustrates the action at a later stage in which the forming slots 44 and deflector strips 54, and thus the zones to which the passage of air through the fibrous layer is confined, have all moved to the left of their original position and have enabled the fibrous strip to continue rolling to form a spirally wrapped unitary strand.

FIG. 8 illustrates the spirally wrapped, unitary strand S in substantially completed form wherein the forming slots 44 and air deflector strips 54 have moved to their farthest-left strand-forming position. The completed :strand product S is illustrated in slightly exploded form in FIG. 13 which clearly illustrates the spiral wrapping of the substantially parallelized or aligned fibers. Such a strand product S has excellent uniformity, substantially constant linear density and a minimum of thin, weak portions or thick, bulky sections. The individual fibers each lie in a spirally-shaped surface having-more than one convolution and which is wrapped into a unitary strand construction. A plurality of spiral convolutions up to three, four or more is obtainable if the, fibrous strips into which the card layer was initially subdivided are sufiiciently wide.

The foraminoussupporting screen moves beyond the end of the vacuum box 24 and is directed downwardly (FIG. 1) carrying the strands S onwardly to'conventional twisting devices, such as a flyer-twister (not shown) or other processing or treating means, asdesired.

A guide roll 62 is provided to direct the foraminous supporting screen 60 upwardly, where it passes between suitably positioned tensioning and tracking

rollers

64 and 66. Roll 66 may be adjusted vertically so as to control the tension in the foraminous supporting screen 60. 7 Roll 64 may be selectively and positively driven by a conventional'variable speed device (such as a Reeves drive) which drives a belt 68 and pulley 70 at any desired or required linear speed. A shaft 72 is provided to transmit the driving power from the driving pulley 70 to the drive roll 64. In the event that a simpler, more direct drive is desired, guide roll 62 may be independently directly. driven from a source of power (not shown) as desired or required.

The foraminous supporting screen 60 1 is thus independently driven ata surface. linear speed which is at least equal to the surface peripheral speed of the doffing cylinder 22, and preferably greater than that speed, in order to draft the fibrous web and increase its fiber orientation in the machine direction. This speed ratio of the foraminous supporting screen 60 to the dotfing cylinder is preferably greater than 1:1 and may be increased to 3:1 or 5:1 or

even higher depending upon the extent of the drafting desired or the fiber parallelism or alignment required. Within the more commercial aspects of the present invention, a speed ratio of from about 2:1 to about 4:1 has been found most advantageous.

The importance of the positioning and size of the guide nip roll 36 is to be appreciated at this time. In order to properly draft the fibers which are to be dofied from the dofiing cylinder 22 by the suction applied at the nose portion of the vacuum box 24 and transferred to the conveyor belt 60, it is necessary that the distance between the point of removal of the fibers from the doffing cylinder 22 to the point of pressing contact between the guide nip roll 36 and the conveyor belt 60 be less than the average staple length of the fibers in the web. If this distance is greater than the average staple length of the fibers, the drafting will be unsatisfactory for the purposes of the present invention.

The size of the guide nip roll is also an important consideration inasmuch as the use of the guide'nip roll which is too large will prevent its proper locating insofar as the critical distance between the point of fiber removal on the dofling cylinder and the gripping point of the dofl'ed fibers by the cooperating guide nip roll and the conveyor belt is concerned. Use of too small a guide nip roller is also to be cautioned against inasmuch as such 9 increases the tendency of the 'doffed fibers to wrap thereabout and not transfer properly to the conveyor belt. The circumference of the guide nip roll should therefore be greater than the average staple length of the fibers being dofied in order to prevent such undesirable wrapping.

It is therefore seen that the drafting of the fibers is accomplished by the greater linear speed of the conveyor belt on and the cooperating nip roll 36, as compared to the lesser peripheral linear speed of the doffing cylinder 22, taken .in conjunction with the grip on the fibers by the guide nip roll 36 and the conveyor belt 60, as the fibers are doffed from the dofiing cylinder;

The guide nip roll 36 possesses an additional function of providing for the removal of the dotted fibers from the peripheral surface of the doffing cylinder at a very sharp angle of depa-rturewhich usually is greater than 45 and approaches 90in many cases (see FIG. 2). In this way, the dotted fibrous web is quickly and more reliably removed fromthe dofling cylinder and is likely to drift back to the dofling cylinder as it would tend to do if the angle of departure were low. Measurement of the angle of departure is very difiicult inasmuch as the surface of the conveyor belt and the surface of the dofling cylinder are theoretically tangential at their point of proximity but an understanding .is obtained from FIG. 3 wherein it is noted that the conveyor belt is very quickly curved from a convex configuration to a concave configuration by the guide nip roll whereby the sharpness of the departure angleis increased rapidly. Additionally, the guide nip roller 36 promptly grips the fibers and presses them adheringly against the conveyor belt 64 thereby making the frictional engagement of the fibers with the conveyor belt more secure to decrease even further the possibility of their drifting back to the doffing cylinder.

Another aspect of the present inventive concept is to be noted at this time in that the foraminous supporting screen 66, if driven at a surface linear speed which is lessthan the surface peripheral speed of the doifing cylinder 22, will condense the fibrous web and increase its density (grains per square yard) and simultaneously decrease its fiber orientation in the long or machine direction. The use of such lower ratios, which may be as low as' 1:2, 1:3 or less, increases the isotropic characteristics of the web to a point wherein substantially an isotropic fibrous web containing fibers substantially at random may be obtained. Such an isotropic web, although not useful for the preparation of strands, rovings, yarns and the like in accordance with the present invention, possesses many other uses for which isotropic characteristics are desired. It is therefore seen that apparatus and methods are provided according to the. present inventive concept of changing the fiber orientation of the fibrous web, eitherto an increased or a decreased degree, simultaneously with its removal from the surface upon which it is formed.

In PEG. 9, there is illustrated a modification of the forming plate and cooperating forming slots which utilizes the same pneumatic principles previously described. A forming plate 138 is provided which fits upon and rests upon the upper surface of a vacuum box similar to vacuum box 24. The forming slots 144, however, are bifurcated and somewhat generally having a slanting Y-configuration comprising a tapered base portion 143 and angularly extending arms. 145 and 147.

Short extensions

149 and 151 are provided at the ends of the

arms

145 and 147, respectively, and extend substantially in the machine direction or the direction of predominant orientation of the fibers in the starting web.

v A foraminous supporting screen 160 which is similar in construction and operation to previously-described fora-ruinous supporting screen 60 is provided and moves along upon the surface of the forming plate 138. Positioned above the foraminous supporting screen 160 is an air deflector plate 146 which is similar in operation and function to air deflector plate 46. The main difference between the air deflector plate 146 and the air deflector plate 46 is that the air deflector plate 146 is formed in a one-piece integral construction. .It is basically similar, however, and also has a forwardly positioned support 148 and a rearwardly positioned support 15f) and connecting deflector strips 154.

As noted in FIG. 9, the air deflector strips 154 have a forwardly extending portion 153 which extends generally in the machine direction and a rearwardly extending portion 155 which is tapered and which is positioned at an angle to the direction of fiber movement. The air deflector strip 154 possesses a configuration so that it overlies the bifurcated forming slot 144 and controls the flow of air thereinto. The lower surface of the air deflector strips 154 is curved or tapered as shown in FIGS. 10 through 12 in order to properly control and direct the fiow of the air currents into the forming slots- 144. Open sections 157 are provided in the air deflector plate 146 in order to permit the free flow of air around the air deflector strips 154, through the fibrous web, then through the foraminous supporting screen 169 and finally through the bifurcated forming slots 144 in the upper surface of the forming plate 138.

It will be appreciated that a fibrous web moving in the direction indicated in FIG. 9 willbe initially subdivided into a plurality of individual fibrous strips. This subdivision is accomplished by the deflected air flow on both the right and left sides of the respective air deflector strips 154.

FIG. 10 illustrates the'division ofthe fibrous web into fibrous strips at an early stage in the formation ofthe desired st-rand product. The substantially vertical flow of the air at the left side of the air deflector strip 154 passing through the web directed overthe slotted portion 149 holds that portion of the web in position. The deflected portion of the air passing around theright side of the air deflector strip 154 and through the portion 151 of the forming slot divides the fibrous web into a plurality of fibrous strips and tends to roll the right side of each fibrous strip inwardly in spiral fashion to form a strand product S.

FIG. 11 shows an intermediate stage of thefor-mation of a strand product and discloses the rolling inwardly of the right side of the fibrous strip.

FIG. 12 illustrates a substantially completed, spirallywrapped strand product. At this stage, the strand is sub stantially complete except for a slight compacting action when the strand passes the extreme end of the rearwardly extending tapered portion 143 of the forming slot 144.

With reference to FIG. 9, it is to be noted that the bifurcated forming slot 144, in addition to tapering substantially in a Y-form, also slants or leans to the right as viewed therein. In the event that the Y-form is symmetrically positioned with respectto the machine direction so that an upright Y is obtained, and the air deflector plate is also made symmetrical so as to overlap both sides of the symmetrical Y-slots, two laterally deflected air flows will result and both sides of the subdivided fibrous strip will be curled inwardly by oppositely directed components of force.

In this way a strand S is obtained which comprises two spirally-wrapped sections connected by the central portion of the fibrous strip, such as shown in FIG. 14. All the fibers therein are substantially parallelized or aligned and the strand pro-duct S has excellent uniformity, substantially constant linear density and a minimum of thin, weak portions or thick, bulky sections. The fibers lie in their spiral surfaces, although the number of spiral convolutions is less than in the case of a singly wrapped strand product as illustrated in FIG. 13. Such a strand is normally undesirable for use in normal textile operations inasmuch as it possesses a weak center section. However, in certain special textile operations it is desirable and I I such a strand may be produced by using a symmetrical Y-form rather than a slanted Y-forrn.

The invention will be further illustrated in greater detail by the following specific examples. It should be understood, however, that although these examples may describe in particular detail some of the more specific features of the invention, they are given primarily for purposes of illustration and the invention in its broader aspects is not to be construed as limited thereto.

Example I The starting fibrous material is a 40-inch wide card web of viscose ray-on fibers weighing about 100 grains per square yard and containing fibers having a length of about 1% inches and a denier of 1 /2. The degree of fiber alignment is about 90%. The card web is drafted by being doffed from the doffing cylinder to the foraminous supporting screen which is moving at a velocity of 40 yards per minute as compared to the peripheral velocity of the doifing cylinder of yards per minute. The apparatus used is illustrated in FIG. 1.

The center-to-center spacing of the forming slots is 3 inches, as measured in a direction at right angles to the machine direction. The length of the forming slots is 8 inches, as measured in the machine direction. The width of the forming slots at their forward position is -76 inch and the width of the forming slots at the rearward position is A inch. The air deflector strips are so positioned that their lower surfaces have an angle of about 15 with respect to the upper surface of the forming plate. The center line of the forming slot has an angle of about 70 with respect to the cross-axis of the web so that the front end of each slot slightly overlaps the rear end of an adjacent slot.

The card web is subdivided into 13 separate strands which are spirally wrapped in cross section. Each strand weighs approximately 7 /2 grains per linear yard of length. The strands are then twisted so that the resulting yarns have increased strength and can be manually handled and processed.

The resulting yarn has excellent uniformity and substantially constant linear density. It is capable of being used in weaving operations.

Example 11 The procedures set forth in Example I are followed substantially as set forth therein with the exception that the starting materals comprise a blend of 50% by weight of the viscose rayon fibers used in Example I and 50% by weight of cotton having a staple length of 1% inches. The degree of fiber alignment is about 90%.

The resulting yarn is comparable to the all viscoserayon yarn obtained in Example 1, taking into account the expected differences due to the substitution of 50% by weight of the viscose ray-on by cotton. The yarn has excellent uniformity and substantially constant linear density and can be readily twisted into yarn. It is capable of being used in Weaving operations.

Example III The procedures set forth in Example I are followed substantially as set forth therein with the exception that the starting materials comprise a blend of by weight of the viscose rayon fibers used in Example I, 50% by weight of cotton having a staple length of 1% inches and 25% by weight of nylon 66 staple fibers having a length of 1 /2 inches and a denier of 1 /2. The degree of fiber alignment is about 90%.

The resulting yarn is comparable to the yarns obtained in Examples I and II, taking into account the expected differences due to the inclusion of 25% by weight of nylon fibers.

Examples IV, V, and VI The procedures set forth in Example I are followed substantially as set forth therein with the exception that 12 the angularity of the lower surface of the airv deflector strips with respect to the forming plate is changed from the 15 value employed therein.

In these examples, the angular relationship is 0, 10, and 20.

Strands are formed under all conditions and are capa bio of being processed into yarns and used in weaving operations.

Examples VII,. VIII and IX The procedures set forth in Example I are followed substantially as set forth therein with the exception that the linear surface velocity r'atio of the foraminous supporting member to the dotting cylinder is changed from the 2:1 ratio employed therein.

In these examples, ratios of 1 /2:1, 2 /221 and 3%:1 are used. The resulting degrees of fiber alignment are about 92% and 94%, respectively.

The yarn obtained using a ratio of' 1 /2 :1 is not as desirable as the yarns obtained using the higher velocity ratios, due most likely to the fact that the drafting of the card Web is less when lower velocity ratios are used. Under conditions of low or no draft, many crossing fibers extend between the strands and cutting devices may be necessary to provide for complete separation of the strands. Under conditions of higher drafting, the fibers are readily removed from the dofiing cylinder and transferred to the nylon foraminous screen in very highly drafted form, usually with greater, than fiber alignment.

Example X 'The procedures of Example I are followed substantially as set forth therein except that the forming slots are /4 inch wide for their full length and are not tapered.

Satisfactory strands are prepared and are comparable to the strands produced in Example I.

Example XI The procedures of Example I are followed substantially as set forth therein withthe exception that the forming plateand air deflector plate of FIG. 9 are used therein. The dimensions of the bifurcated forming slots are as follows: the total length ofthe slot as measured in the machine direction is 8 inches; the center-to-center distance between adjacent slots is 2 /8 inches; the spacing between the upper parallel legs of the bifurcated portion is 1%; inches; the length in the machine direction of the upper parallel leg portions is 1 4 inches; and the angle taken by the center line of the bifurcated slot is approximately 75.

The dimensions of the air deflector strips are as follows: the length of the strip is 8% inches; thewidth of the forward portion of the strip is 1 inches; the length of the forward portion of the strip is 3 inches; the

width of the strip at the most rearward portion is inch;

and the angle taken by the center line of the rearward portion of the strip is about 75.

The resulting yarn is comparable to the yarn obtained in Example I. It has excellent uniformity and substantially constant'linear density. It is capable of being used 1n weaving operations.

Examples XII, XIII and XIV The procedures set forth in Example I are followed substantially as set forth therein with the exception that the starting material weighs about 50, 150, and grains per square yard. Individual strands are produced therefrom and have excellent uniformity and substantially constant linear density. The strands are capable of being twisted into yarns, with the lighter strands being capable of being twisted to a higher and harder degree. The yarns are capable of being used in weaving operations.

Example XV The procedures set forth in Example I are followed substantially as set forth'therein with the exception that appended hereto.

13' the air deflector strips are removed and the air is permitted to flow directly into the forming slots without being deflected in any way. Strand formation is not accomplished and such an operation is commercially impracticable for producing strands.

This example illustrates the necessity for the air deflector strips and the creation of a laterally deflected air flow having the required component of force to roll the divided fibrous strips inwardly to form the desired unitary strands.

Although several specific examples of the inventive concept have been described, the same should not be construed as limited thereby nor to the specific values mentioned or constructions described but to include other values and other constructions as set forth in the claims It is understood that any suitable changes, modifications and variations may be made without departing from the spirit and scope of the invention.

What is claimed is:

1. The method of converting a fibrous layer contain- ;ing aligned fibers into a plurality of unitary strands which comprises: causing a gaseous medium to flow in the direction of and through said fibrous layer; and deflecting saidv gaseous medium to divide it into a plurality of portions prior to being passed through said fibrous layer, said plurality of portions comprising certain spaced portions which exert components of force on said layer in a direction generally perpendicular to the plane thereof to hold spaced areas of said layer in position and other spaced portions which are simultaneously deflected to divide said layer into a plurality of strips, each said deflected portion exerting a component of force on a fibrous strip in a direction generally parallel to the plane thereof and toward a respective holding portion, whereby at least one edge of each strip is individually rolled inwardly upon itself to form a plurality of compact unitary strands.

2. The method of converting a fibrous layer containing aligned fibers into a plurality of unitary strands which comprises: continuously moving said fibrous layer; causing. a gaseous medium to flow in the direction of and through said fibrous layer while it is being continuously moved; and deflecting said gaseous medium to divide it into a plurality of portions prior to being passed through said fibrous layer, said plurality of portions comprising certain spaced portions which exert components of force on said layer in a direction generally perpendicular to the plane thereof to hold spaced areas of said layer in position and other spaced portions which are simultaneously deflected to divide said layer into a plurality of strips, each said deflected portion exerting a component of force on a fibrous strip in a direction generally parallel to the plane thereof and towarda respective holding portion, whereby at least one edge of each strip is individually rolled inwardly upon itself to form a plurality of compact unitary strands;

3. The method of converting a fibrous layer containing aligned discontinuous fibers into a plurality of unitary strands which comprises: drafting said fibrous layer to increase the fiber alignment thereof in the long direction; passing a gaseous medium through said drafted fibrous layer; and deflecting said gaseous medium to divide it into a plurality of portions prior to being passed through said drafted fibrous layer, said plurality of portions comprising certain spaced portions which exert components of force on said layer in a direction generally perpendicular to the plane thereof to hold spaced areas of said layer in position and other spaced portions which are simultaneously deflected to divide said layer into a plurality of strips,

each said deflected portion exerting a component of force rolled inwardly upon itself to form a plurality of compact unitary strands.

4. The method of converting a fibrous layer containing aligned discontinuous fibers into a plurality of unitary strands which comprises: drafting said fibrous layer at a drafting ratio of from about 2:1 to about 4:1 to increase the fiber alignment thereof in the long direction; passing a gaseous medium through said drafted fibrous layer; and deflecting said gaseous medium to divide it into a plurality of portions prior to being passed through said drafted fibrous layer, said plurality of portions comprising certain spaced portions which exert components of force on said layer in a direction generally perpendicular to the plane thereof to hold spaced areas of said layer in position and other spaced portions which are simultaneously deflected to divide said layer into a plurality of strips, each saiddeflected portion exerting a component of force on a fibrous strip in a direction generally parallel to the plane thereof and toward a respective holding portion, whereby at least one edge of each strip is individually rolled inwardly upon itself to form a plurality of compact unitary strands.

5. Apparatus for converting a fibrous layer containing aligned fibers into a plurality of unitary strands which comprises: vacuum means for passing a gaseous medium through said layer; deflector means to divide said gaseous medium into a plurality of portions; said vacuum means having openings therein so positioned with respect to said deflector means that spaced portions of said gaseous medium exert components of force on said layer in a direction generally perpendicular to the plane thereof to hold spaced areas of said layer in position and other spaced portions of said gaseous medium are simultaneously deflected to divide said layer into a plurality of strips; each said deflected portion exerting a component of force on a fibrous strip in a direction generally parallel to the plane thereof and toward a respective holding portion, whereby at "least one edge of each strip is individually rolled inwardly upon itself to form a plurality of compact unitary strands.

6. Apparatus for converting a fibrous layer containing aligned fibers into a plurality of unitary strands which comprises: vacuum means for passing a gaseous medium through said layer; a plurality of deflector plates to divide said gaseous medium into a plurality of portions; said vacuum means having a plurality of openings therein so positioned with respect to said deflector plates that spaced portions of said gaseous medium exert components of force on said layer in a direction generally perpendicular to the plane thereof to hold spaced areas of said layer in position and other spaced portions of said gaseous medium are simultaneously deflected to divide said layer into a plurality of strips; each said deflected portion exerting a component of force on a fibrous strip in a direction generally parallel to the plane thereof and toward arespective holding portion, whereby at least one edge of each strip is individually rolled inwardly upon itself to form a plurality of compact unitary strands.

7. Apparatus as defined in claim 6 wherein the deflector plates are angularly slanted with respect to the plane of the fibrous layer.

8. Apparatus as defined in claim 6 wherein the deflector plates are angularly slanted up to as high as about 30 with respect to the plane of the fibrous layer.

9. Apparatus as defined in claim 6 wherein the deflector plates are angularly slanted at an angle of from about 5 to about 20 with respect to the plane of the fibrous layer.

10. Apparatus as defined in claim 6 wherein the deflector plates and the openings in the vacuum means are elongated and are angularly slanted with respect to the fiber alignment of the fibrous layer.

11. Apparatus as defined in claim 10 wherein the leading edge of an opening in the vacuum means at least coincides with the trailing edge of an adjacent opening,

as determined by a line extending in the direction of fiber alignment. 12.; Apparatus as defined in claim 10 wherein the leading edge of an opening in the vacuum means overlaps the trailing edge of an adjacent opening, as determined by a line extending in the direction of fiber alignment 13. Apparatus for coverting a fibrous layer containing aligned fibers into a plurality of unitary strands which comprises: vacuum means for passing a gaseous medium through said layer; a plurality of deflector plates to divide said gaseous medium intd a plurality of portions; said vacuum means having a plurality of elongated slotted openings therein so positioned with respect to said deflector plates that spaced portions of said gaseous medium exert components of force on said layei" in a direction generally perpendicular to the plane thereof to hold spaced areas of said layer in position and other spaced portions of said gaseous medium are simultaneously deflected to divide said layer into a plurality of strips; each said deflected portion exerting a component of force on a fibrous strip in a direction generally parallel to the plane thereof and toward a respective holding portion, whereby at least one edge of each strip is individually rol'led inwardly upon itself to form a plurality of compact unitary strands.

14. Apparatus as defined in claim 13 wherein the deflector plates are Wider and longer than the elongated slotted openings in the vacuum means and prevent the direct access of gaseous medium thereto.

15. Apparatus for converting a fibrous layer containing aligned fibers into a plurality of unitary strands which comprises: vacuum means for passing a gaseous medium through said layer; a plurality of deflector plates to divide said gaseous medium into a plurality of portions; said vacuum means having a plurality of bifurcated openings therein so positioned with respect to said deflector plates that spaced portions of said gaseous medium exert components of force on said layer in a direction generally:

perpendicular to the plane thereof to hold spaced areas of said layer in position and other spaced portions of said gaseous medium are simultaneously deflected to divide said layer into a plurality of strips; each said deflected portions exerting a component of force on a fibrous strip in a direction generally parallel to the plane thereof and toward a respective holding portion, whereby at least one edge of each strip is individually rolled inwardly upon itself to form a plurality of compact unitary strands.

16. Apparatus for converting a fibrous layer containing aligned fibers into a plurality of unitary strands which comprises: means for continuously moving said fibrous layer; vacuum means for passing a gaseous medium through said layer while it is being continuously moved; deflector means to divide said gaseous medium into a plurality of portions; said vacuum means having openings therein so positioned with respect to said deflector means that spaced portions of said gaseous medium exert components of force on said layer in a direction generally perpendicular to the plane thereof to hold spaced areas of said layer in position and other spaced portions of said gaseous medium are simultaneously deflected to divide said layer into a V plurality of strips; each said deflected portion exerting a component of force on a fibrous strip in a direction generally parallel to the plane thereof and toward a respective holding portion, whereby at least one edge of each strip is individually rolled inwardly upon'itself to form a plurality of compact unitary strands.

17. Apparatus for converting a fibrous layer containing aligned fibers into a plurality of unitary strands which comprises: a foraminous supporting screen for moving said fibrous layer; vacuum means positioned under said foraminous supporting screen for passing a gaseous medium through said layer; deflector means to divide said gaseous medium into a plurality of portions; said vacuum means having openings therein so positioned with respect to said deflector means that spaced portions of said gaseous medium exert componentsof force on said layer in a di- Cir rection generally perpendicular to the plane thereof to hold spaced areas of said layer in position and other spaced portions of said gaseous medium are simultaneously deflected to divide said layer into a plurality of strips; each said deflected portion exerting a component of force on a fibrous strip in a direction generally parallel to the plane thereof and toward a respective holding portion, whereby at least one edge of each strip is individually rolled'inwardly upon itself to form a plurality of compact unitary strands. 18. Apparatus for converting a fibrous layer containing aligned discontinuous fibers into a plurality of unitary strands which comprises: means for drafting said fibrous layer to increase the fiber alignment thereof in the long direction; vacuum means for passing a gaseous medium through said drafted fibrous layer; deflector means to divide said gaseous medium into a plurality of portions; said vacuum means having openings therein so positioned with respect to said deflector means that spaced portions of said gaseous medium exert components of force on said layer in a direction generally perpendicular to the plane thereof to hold spaced areas of said layer in position and other spaced portions of said gaseous medium aresirnultaneously deflected to divide said layer into a plurality of strips; each said deflected portion exerting a component of force one fibrous strip in a direction generally parallel to the plane thereof and toward a respective holding portion, whereby at least one edge of each strip is individually rolled inwardly upon itself to form a plurality of compact unitary strands.

19. Apparatus for converting a fibrous layer containing aligned fibers into a plurality of unitary'strands which comprises: a rotatable surface for carrying a fibrous layer of aligned fibers, vacuum means for passing a gaseous medium through said layer, a moving surface passing over said vacuum means, suction means for transferring said layer from said rotatable surface to said moving surface, a plurality of deflector plates to divide said gaseous medium into a plurality of portions, said vacuum means having openings therein so positioned with respect to said deflector plates that spaced portions of said gaseous medium exert components of force on said layer in a direction generally perpendicular to the plane thereof to hold spaced areas of said layer in position and other spaced portions of said gaseous medium are simultaneously deflectedto divide said layer into a plurality of strips, each said deflected portion exerting a component of force on a fibrous strip in a direction generally parallel to the plane thereof and toward a respective holding portion, whereby at least one edge of each strip is individually rolled inwardly upon itself to form a plurality of compact unitary strands.

20. Apparatus for converting a fibrous layercontaining aligned fibers into a plurality of unitary strands which comprises: a rotatable surface for carrying a fibrous layer of aligned fibers, vacuum means for passing a gaseous medium through said layer, a moving surface passing over said vacuum means, suction means spaced from about 0.005 inch to 0.125 inch from said rotatable surface for transferring said layer from said rotatable surface to said moving surface, a plurality of deflector plates to divide said gaseous medium into a plurality ofportions, said vacuum means having openings therein so positioned with respect to said deflector plates that spaced portions of said gaseous medium exert components of force on said layer in a direction generally perpendicular to the plane thereof to hold spaced areas of said layer in position and other spaced portions of said gaseous medium are simultaneously deflected to divide said layer into a plurality of strips, each said deflected portion exerting a component of force on a fibrous strip in a direction generally parallel to the plane thereof and toward a respective holding portion, whereby at least one edge of each strip is individually rolled inwardly upon itself to form a plurality of compact unitary strands.

21. Apparatus for converting a fibrous layer containing aligned fibers into a plurality of unitary strands which comprises: a rotatable surface for carrying a fibrous layer of aligned fibers, vacuum means for passing a gaseous medium through said layer, a moving surface passing over said vacuum means, suction means spaced from about 0.015 inch to 0.030 inch from said rotatable surface for transferring said layer from said rotatable surface to said moving surface, a plurality of deflector plates to divide said gaseous medium into a plurality of portions, said vacuum means having openings therein so positioned with respect to said deflector plates that spaced portions of said gaseous medium exert components of force on said layer in a direction generally perpendicular to the plane thereof to hold spaced areas of said layer in position and other spaced portions of said gaseous medium are simultaneously deflected to divide said layer into a plurality of strips, each said deflected portion exerting a component of force on a fibrous strip in a direction generally parallel to the plane thereof and toward a respective holding portion, whereby at least one edge of each strip is individually rolled inwardly upon itself to form a plurality of compact unitary strands.

22. Apparatus for converting a fibrous layer containing aligned fibers into a plurality of unitary strands which comprises: vacuum means for passing a gaseous medium through a fibrous layer, means for passing a fibrous layer containing aligned fibers over said vacuum means, a plurality of deflector plates to divide said gaseous medium into a plurality of portions, said vacuum means having openings therein so positioned with respect to said deflector plates that spaced portions of said gaseous medium exert components of force on said layer in a direction generally perpendicular to the plane thereof to hold spaced areas of said layer in position and other spaced portions of said gaseous medium are simultaneously deflected to divide said layer into a plurality of strips, each said deflected portion exerting a component of force on a fibrous strip in a direction generally parallel to the plane thereof and toward a respective holding portion, whereby at least one edge of each strip is individually rolled inwardly upon itself to form a plurality of compact unitary strands.

23. Apparatus for converting a fibrous layer containing aligned fibers into a plurality of unitary strands which comprises: vacuum means for passing a gaseous medium through a fibrous layer, means for passing a fibrous layer containing aligned fibers over said vacuum means, a plurality of deflector plates to divide said gaseous medium into a plurality of portions, said vacuum means having a plurality of slotted openings therein so positioned with respect to said deflector plates that spaced portions of said gaseous medium exert components of force on said layer in a direction generally perpendicular to the plane thereof to hold spaced areas of said layer in position and other spaced portions of said gaseous medium are simultaneously deflected to divide said layer into a plurality of strips, each said deflected portion exerting a component of force on a fibrous strip in a direction generally parallel to the plane thereof and toward a respective holding portion, whereby at least one edge of each strip is individually rolled inwardly upon itself to form a plurality of compact unitary strands.

24. The method of converting a fibrous layer containing aligned fibers into a plurality of unitary strands which comprises: moving a fibrous layer containing aligned fibers over a supporting surface, subjecting said fibrous layer while on said supporting surface to a vacuum thereby causing a gaseous medium to flow in the direction of and through said fibrous layer and deflecting said gaseous medium to divide it into a plurality of portions prior to being passed through said fibrous layer, said plurality of portions comprising certain spaced portions which exert components of force on said layer in a direction generally perpendicular to the plane thereof to hold spaced areas in said layer in position and other spaced portions whichare simultaneously deflected to divide said layer into a plurality of strips, each said deflected portion exerting a component of force on a fibrous strip in a direction generally parallel to the plane thereof and toward a respective holding portion, whereby at least one edge of each strip is individually rolled inwardly upon itself to form a plurality of compact unitary strands.

25. The method of converting a fibrous layer containing aligned fibers into a plurality of unitary strands which comprises: forming a fibrous layer containing aligned fibers on a rotatable surface, applying suction to the fibrous layer on the rotatable surface and transferring said layer from said rotatable surface to a supporting surface, moving said layer over said supporting surface, subjecting said fibrous layer while on said supporting surface to a vacuum thereby causing a gaseous medium to flow in the direction of and through said fibrous layer and deflect ing said gaseous medium to divide it into a plurality of portions prior to being passed through said fibrous layer, said plurality of portions comprising certain spaced por tions which exert components of force on said layer in a direction generally perpendicular to the plane thereof to hold spaced areas in said layer in position and other spaced portions which are simultaneously deflected to divide said layer into a plurality of strips, each said deflected portion exerting a component of force on a fibrous strip in a direction generally parallel to the plane thereof and toward a respective holding portion, whereby at least one edge of each strip is individually rolled inwardly upon itself to form a plurality of compact unitary strands.

26. The method of converting a fibrous layer into a plurality of unitary strands which comprises: forming a fibrous layer on a rotatable surface, applying suction to the fibrous layer on the rotatable surface and transferring said layer from said rotatable surface to a supporting surface and simultaneously drafting the fibrous layer, moving said drafted layer over said supporting surface, subjecting said drafted fibrous layer while on said supporting surface to a vacuum thereby causing a gaseous medium to flow in the direction of and through said drafted fibrous layer and deflecting said gaseous medium to divide it into a plurality of portions prior to being passed through said drafted fibrous layer, said plurality of portions comprising certain spaced portions which exert components of force on said layer in a direction generally perpendicular to the plane thereof to hold spaced areas in said layer in position and other spaced portions which are simultaneously deflected to divide said layer into a plurality of strips, each said deflected portion exerting a component of force on a fibrous strip in a direction generally parallel to the plane thereof and toward a respective holding portion, whereby at least one edge of each strip is individually rolled inwardly upon itself to form a plurality of compact unitary strands.

References Cited by the Examiner UNITED STATES PATENTS 1,765,571 6/1930 Edson et a1. 2,274,424 2/1942 Miller l9150 2,274,425 2/ 1942 Miller 19150 3,018,521 1/1962 Harmon 19150 3,135,023 6/1964 Kalwaites 19151 X FOREIGN PATENTS 25,629 2/1920 Denmark.

17,199 1903 Great Britain.

21,915 1902 Great Britain.

24,136 1902 Great Britain.

DONALD W. PARKER, Primary Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 ,230,584 January 25, 1966 Frank Kalwaites It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 2 line 55 for "made-made" read man-made column 4 line 31 for "strating" read starting column 7 line 30 for "untiary" read unitary column 9, line 19 after "is" insert less line 63, for "having" read have column 11, line 26, for "5/6" read 5/8 Signed and sealed this 7th day of February 1967 SEAL) )RNEST W. SWIDER EDWARD J. BRENNER Lttesting Officer Commissioner of Patents

Claims

1. THE METHOD OF CONVERTING A FIBROUS LAYER CONTAINING ALIGNED FIBERS INTO A PLURALITY OF UNITARY STRANDS WHICH COMPRISES: CAUSING A GASEOUS MEDIUM TO FLOW IN THE DIRECTION OF AND THROUGH SAID FIBROUS LAYER; AND DEFLECTING SAID GASEOUS MEDIUM TO DIVIDE IT INTO A PLURALITY OF PORTIONS PRIOR TO BEING PASSED THROUGH SAID FIBROUS LAYER, SAID PLURALITY OF PORTIONS COMPRISING CERTAIN SPACED PORTIONS WHICH EXERT COMPONENTS OF FORCE ON SAID LAYER IN A DIRECTION GENERALLY PERPENDICULAR TO THE PLANE THEREOF TO FLECTED PORTION EXERTING A COMPONENT OF FORCE ON A FIBROUS STRIP IN A DIRECTION GENERALLY PARALLEL TO THE PLANE THEREOF AND TOWARD A RESPECTIVE HOLDING PORTION, WHEREBY AT LEAST ONE EDGE OF EACH STRIP IS INDIVIDUALLY ROLLED INWARDLY UPON ITSELF TO FORM A PLURALITY OF COMPACT UNITARY STRANDS.

5. APPARATUS FOR CONVERTING A FIBROUS LAYER CONTAINING ALIGNED FIBERS INTO A PLURALITY OF UNITARY STRANDS WHICH COMPRISES: VACUUM MEANS FOR PASSING A GASEOUS MEDIUM THROUGH SAID LAYER; DEFLECTOR MEANS TO DIVIDE SAID GASEOUS MEDIUM INTO A PLURALITY OF PORTIONS; SAID VACUUM MEANS HAVING OPENINGS THEREIN SO POSITIONED WITH RESPECT TO SAID DEFLECTOR MEANS THAT SPACED PORTIONS OF SAID GASEOUS MEDIUM EXERT COMPONENTS OF FORCE ON SAID LAYER IN A DIRECTION GENERALLY PERPENDICULAR TO THE PLANE THEREOF