US3082505A

US3082505A - Needling process for manufacturing textile products

Info

Publication number: US3082505A
Application number: US155945A
Authority: US
Inventors: Richard D Wells
Original assignee: Crompton and Knowles Corp
Current assignee: Crompton and Knowles Corp
Priority date: 1958-06-13
Filing date: 1961-11-30
Publication date: 1963-03-26
Anticipated expiration: 1980-03-26

Description

R. D. WELLS March 26, 1963 NEEDLING PROCESS FOR MANUFACTURING TEXTILE PRODUCTS Original Filed June 13, 1958 4 Sheets-Sheet 1 I 5 5 m L 4 g a w G 1 4 ll j 3 F A m 1 3 3 W U a A H HHHHP 7 H 3 v hl l ln l n ..I w H U HHHHWH 7 mm 5 I HHHHH HI F HHHHH W m 6 Q a 7 G w I N 2 F UNI]; m m;- m F w |l|\/l|||||\ l l w s, 4 Q u. 2 o o o H M 0 o o l H G l O o O W l II W F. o o...o.. .H F 2 W FIG. l5 1' INVENTOR RICHARD D. WELLS @ewwT #kj ATTORNEY March 26, 1963 R. D. WELLS 3,082,505

NEEDLING PROCESS FOR MANUFACTURING TEXTILE PRODUCTS Original Filed June 13, 1958 4 Sheets-Sheet z FIG. 8

INVENTOR RICHARD D. WELLS ATTORNEY March 26, 1963 R. D. WELLS 3,082,505

NEEDLING PROCESS FOR MANUFACTURING TEXTILE PRODUCTS Original Filed June 13, 1958 4 Sheets-Sheet 5 49 l"

FIG l

54, 54

56 83 83 51 so an 5 E 58 55%; wac m i '85 84 a 60 N as 59 W3 FIG. ll 3 W 2. 7 82 L {1| mvzwoa 1 P 57 w RICHARD-Q WELLS ATTORNEY QQQMT.

March 26, 1963 R. D. WELLS 3, 0

NEEDLING PROCESS FOR MANUFACTURING TEXTILE PRODUCTS Original Filed June 13, 1958 4 Sheets-Sheet 4 FIG. 32

INVENTQR RICHARD D. WELLS ATTORNEY 3,082,505 NEEDLING PROCESS FOR MANUFACTURING TEXTILE PRODUCTS Richard I). Wells, Westwood, Mass, assignor to Crompton & Knowles Corporation, Worcester, Mass, a corporation of Massachusetts Original application June 13, 1958, Ser. No. 741,859,

now Patent No. 3,925,586, dated Mar. 20, 1962. Divided and this application Nov. 30, 1961, Ser. No. 155,945

14 Claims. (Cl. 28-722) The application is a division of my copending application, Serial No. 741,859, filed June 13, 1958, now Patent 3,025,586 issued March 20, 1962 which application relates to an apparatus for treating or acting, as by needling, on a group of fibers loosely assembled in a web. This divisional application relates more particularly to a needling process set forth in the above identified application but not claimed therein.

Current methods for manufacturing so-called nonwoven fabrics ordinarily employ some form of adhesive to hold the fibers together, or depend upon the use of thermoplastic fibers which can be stuck to each other by the heating process. Such fabrics, however, do not have the same feel or texture commonly found in knit and woven fabrics. In order to attain a more acceptable feel it is an important object of the invention to eliminate the use of objectional amounts of adhesive or thermoplastic fibers by providing methods and apparatus to effect mechanical interlocking or bonding of fibers.

The batt or web of fibers ordinarily does not have suificient strength to withstand the strains of ordinary usage and it is a further object of the invention to provide methods and apparatus for gathering certain of the fibers into reenforcing yarn-like structures which act to strengthen and reenforce the web.

By way of illustrating the invention, five types of structure are set forth in one of which the reenforcing zones or structures are transverse of the plane of the web and ex tend from at least one surface of the web into the latter in such manner as to gather or twist fibers in concentrations which are connected to each other by fibers which partake only partly of the twisted concentrations. In the second form of the invention reenforcing yarn-like structures are formed lengthwise in a single 'batt or web of fibers, and in the third form two batts or webs are brought into tangential or at least surface contact with each other and the reenforcing structures are made from fibers drawn from both webs. In the fourth form reenforcing structures are formed on both sides of a web. In the fifth form the fibers are gathered together to form a yarn-like structure which is not necessarily connected to any similar structure but can be used either as a step for further treatment to produce yarns or can be used directly as produced as will be set forth hereinafter.

In order to produce the reenforcing yarn-like structures it is an important object of the invention to subject the fibers in localized zones of the web to rotary action which will coil at least some of the fibers on themselves and wherein some of the coiled fibers extend into adjacent areas of the web to have frictional contact with other fibers not necessarily entangled in the yarn structure.

It is a further object of the invention to use fibers some of which will have a length suflicient to extend from one reenforcing structure to an adjacent similar structure and become coiled into both structures so that the lateral strength of the web is increased.

It is a still further object of the invention to subject localized areas of the web to the action of rotating needles which when rotated are eifective due to characteristics such as barbs to collect some of the fibers into the aforesaid yarn-like structures. As the needles are rotated on States Patent their axes the web is fed forwardly in a direction away from the needles in order to produce continuous yarn-like structures.

Many nonwoven fabrics lack the property of drape and are also only slightly elastic in any direction, particularly lengthwise and crosswise. It is an important object of the present invention to provide a process and apparatus to produce a product in the nature of a nonwoven fabric which is capable of elastic stretch lengthwise and also crosswise.

This latter characteristic of the fabric is attained by coiling some of the fibers helically so that the yarn-like structure has lengthwise elasticity and spirally coiling other fibers, or parts of those coiled helically, to permit uncoiling to provide transverse elasticity.

In the accompanying drawings examples are given of each of the five types of structures already mentioned and apparatus for producing the structures and methods employed to produce them are described.

FIG. 1 is a combined plan and side view ofa fabric made according to the first form of the invention wherein short reenforcing structures are assembled out of fibers in the web and extend at least partway through the web from one side to the other,

FIG. 2 is a view similar to FIG. 1 but wherein lengthwise yarn-like structures have been formed in a single web of fibers,

FIG. 3 is a view similar to FIG. 2 but wherein the web has been made by joining two distinct webs by reenforcing yarn-like structures located between the two webs and having their fibers drawn from each of the webs so that the latter are closely bonded to each other,

FIG. 4 is a view showing an end of a fabric similar to that shown in FIG. 2 but with a row of reenforcing yarnlike structure on both sides thereof,

FIG. 5 is a view similar to FIG. 1 but showing a single yarn-like structure formed as such without reference to a fabric,

FIG. 6 is a side elevation in diagrammatic form showing a machine for producing the type of fabric shown in FIG. 1,

FIG. 7 is a diagrammatic elevation of a machine looking in the direction of feed of the web to be acted on for producing for instance the types of fabrics shown in FIGS. 2, 3 or 4,

FIG. 8 is a diagrammatic side view looking in the direction of arrow 8, FIG. 7,

FIG. 9 is an enlarged section on line 99, FIG. 8,

FIG. 10 is a side elevation in the direction of arrow 10, FIG. 9, parts being broken away and parts in section,

FIG. 11 is a plan view looking in the direction of arrow 11, FIG. 9,

FIG. 12 is a diagrammatic view showing part of the structure shown in FIG. 10 in a somewhat diflerent position for producing for instance the type of fabric shown more specifically in FIG. 2,

FIG. 13 is a diagrammatic view showing structure and method for producing the fabric shown in FIG. 4,

FIG. 14 is a plan view in the direction of arrow 14, FIG. 8, parts being omitted, showing the web split into a number of separate tapes or ribbons for forming the single structure shown in FIG. 5,

FIG. 15 is an enlarged section on line 1515, FIG. 2,

FIG. 16 is a diagrammatic view looking in the direction of arrow 16, FIG. 15, illustrating the manner in which a single fiber can be jointed to two adjacent yarn-like structures,

FIG. 17 is an enlarged diagrammatic section on line 17-47, FIG. 3, showing the manner in which two webs can be joined as contemplated in the third form,

FIG. 18 is a diagrammatic plan view showing a varia- 3 tion in the structure shown in FIG. 11 whereby the needles turn in the same direct-ion,

FIG. 19 is a view similar to FIG. 15 but modified to show thefiber relation produced by the variation shown in FIG. '18,

FIG. 20 is similar to FIG. 17 except that the coiling has been done by the structure shown in FIG. 18,

FIG. 21 is a side view on an enlarged scale of a needle such as can be used with the invention,

FIG. 22 shows a fabric such for instance as set forth in FIG. 2 in normal size in full lines and in stretched size in dotted lines,

FIGS. 23 to 26 show fabrics of diflierent forms but all of the general type shown in FIG. 4,

FIG. 27 is a diagrammatic plan view of a fabric made according to the invention showing various fiber relations,

FIGS. 28 to 31 show modified forms of needles which can be used, and

FIG. 32 is a side elevational view with certain of the parts in cross section and showing the structural means to rotate the needles shown in FIG. 13.

Referring more particularly to FIG. 6 which diagrammatically shows a machine to produce the type of fabric illustrated inFIG. 1, frame 10 has upright posts 11 which sup-port a table 12 having abearing 13 slida-ble on each post 11. Extending over and secured in fixed position on the table is a web supporting plate 14 provided with perforations 15 to register with other perforations 16 in a second plate 17 mounted over the plate 14. The plate 17 is mounted for rising and falling motion and has end supports 18 which normally rest on fixed stops 19 which limit down motion of plate 17 The machine has a shaft 26 driven in any convenient manner to which is secured a crank 21 connected by links 22 to feed arms 23 rockable about fixed studs 24. Each arm 23 has a feed pawl 25 which meshes with a ratchet Wheel 26 rotatable on the corresponding stud 24 and secured to a pulley 27. Each pulley drives a belt 28, the belt at the left driving a feed pulley 2,9 for a flexible web feeding belt 30 trained around an idler pulley $1. The belt 28 at the right drives a pulley 32 for a flexible take-off belt 33 trained around an idler pulley 34. A

' take-off board 35 receives material fed to it by belt 33.

Hold pawls 36 prevent retrograde motion of ratchet wheels 26.

A cam 40 is secured to shaft and has a low dwell 41, an incline 42, a high point 43 and a decline 44. The cam engages a roll 45 rotatably mounted on the underside of table 12. Rotatable needles N to be described in detail hereinafter are normally located above plate 17 in register with the openings 16 in the top plate and 15 in the bottom plate.

In the operation of the machine shown in FIG. 17 the web or batt W1, which is made of a large number of loosely assembled fibers, is fed by belt 30 to the space between

plates

14 and 17 when the low'area 41 of cam 40 has let the roll 45 and table 12 down to their low positions. At this time the crank arm 21 will be giving feeding strokes to pawls .to advance belts and 33 to feed the web between the

plates

14 and 17 When the crank arm has made a half turn and starts a reverse motion of the feed pawls 25 the cam 40 will lift the table 12 and plate 14 to elevate the web against the plate 17 and lift it off the supporting stops 19, thereby subjecting the web to some restraint. As the cam continues to turn the

plates

14 and 17 and also the web rise so that the needles N can pass through the holes 16 and continuously rotate in the web to gather fibers into coiled form at spaced intervals as shown for instance at S1, FIG. 1. The holes 15 are provided in plate 14 to permit the needles to go entirely through the web it this is desired. As the crank 21 continues the idle motion of the pawls the cam 40' continues to turn and lower the plate 14. The plate '17, by its weight, will move the web down away from the needles and come to rest on the stops 19. This will complete the operation with respect to a section of the web and the belt 33 will then move the treated web onto the take-01f table or board 35 as the belt 30 feeds the next section of web between

plates

14 and 17. In this Way the web is provided with transverse reenforcing areas of coiled fibers some at least of which extend into adjacent parts of the nontreated web to have frictional holding contact therewith.

The needles may be mounted and operated as shown for instance in FIGS. 7 and 9. In FIG. 7 the driving motor M has a drive lpulley 46 connected by belt 47 to driven pulley 48 secured to the upper end of a vertical shaft 49. As shown more particularly in FIG. 9 the shaft 49 extends down Zthrough a top plate 50 and has secured thereto a gear '51 and continues beyond the latter and has mounted on the lower end thereof a chuck 52 in which the upper end or shank of a needle N is secured. Other chucks 53 similar to chuck 52 are mounted on vertical shafts 54 each having a gear 55 secured thereto. The

gears

51 and 55 mesh, adjacent gears and needles turning in opposite directions; The vertical position of the chucks is determined by a'second plate'56 vertically adjustable by nuts 57 on upright screws 58 the lower ends of which are secured to the frame 59.

As' the motor M turns it causes continuous rotation of shaft 49 which in turn causes continuous rotation of all of the needles and this arrangement can, if desired, be utilized to drive the needles N which are shown in FIG. 6. The lower end of each needle is provided with a barb B off-set slightly from the shank of the needle and it is the barb on each needle which gathers certain of the fibers into the yarn-like structures S1 of FIG. 1. The

shafts

49 and 54 have collets 60 which engage the underside of plate 56 to limit upward motion of the chucks and needles. The gears which are secured to the shafts rest On collars or washers 61 supported by the top of plate 56. In this way vertical adjustment of the plate 56 determines the position of the lower ends of the needles.

When making the fabric shown in FIG. 2 from a single web of fibers the web W2 is fed into a drum 65 which can be turned by means of gear reducer 66 shown in FIG. 7 as being driven by a connecting shaft 67 turned by the motor M. The needles shown in FIG. 12 have been disposed to operate at an angle but in other respects the driving mechanism will be as already described in connection with FIG. 9. The web W2 is fed in the direction of arrow a, FIG. 12, andthe free ends of the needles terminate close to the friction, soft rubber, surface 68 of the drum or cylinder 65. The ends of the needles have the barbs on them extended into the Web and rotate at a speed sufficient to gather fibers into yarn-like assemblages or coils S2 which run lengthwise of the web, these yarn-like structures being to the left of the needle as viewed in FIG. 12.

When producing the fabric shown in FIG. 3 the needles can have the disposition'shown in FIG. 9, that is, upright with their barbed lower ends terminating near the nip between two

cylinders

70 and 71 which turn in opposite directions as indicated by arrows b and c, FIG. 10. These are the drums which are shown in FIGS. 7 and 8 and are driven by the gear reducer 66 so that their angular speed is considerably less than the rotational speed of the needles. Two webs W3A and W313 are trained respectively over the upper parts of the cylinders 7 0 and 71 which may be similar to the drum or cylinder 65. As the drums 7t and 71 turn they draw the webs down to the space or nip between them and cause the two webs to come into surface engagement with each other at a point approximately at the lower end of the needles. As the needles turn their barbs collect fibers from each of the two webs WSA and WBB into yarn-like structure S3 and in this way unite the two webs into a single web W3 which corresponds to the web shown in FIG. 3. The

lower part of FIG. 3 shows the web W3A as at the top and the web WSB as at the bottom with the yarn-like structures S3 connecting these two webs to form the single united web W3. As shown in FIG. 8 the fabric W3 is led down around guide rolls 75 and then to a wind-up roll 74- which can be driven from the reducer 66 somewhat after the manner of driving cloth rolls in looms. A similar wind-up drum or roll can be provided to collect each of the various products set forth herein.

Experience shows that the barbs B can occupy several difierent positions with respect to the line showing the centers of the two cylinders 711 and 71, that is, they can be slightly above the line, on it, or slightly below it. Whatever their position it is desirable that the two webs be under some compression and that the barbs turn on axes which lie on the plate of contact of adjacent surfaces of the two webs W3A and W33. The single web shown in FIG. 2 can be passed between the two

rolls

70 and 71 if desired, and it need not necessarily be made as indicated in FIG. 12.

As shown more particularly in FIG. 9 'web guide means 8t) are provided to compress the webs somewhat before they reach the positions of mutual engagement. This means also prevents the webs from ascending the shanks of the needles and further provide means to arrest vibra tion of the needles. The means 3'1 comprises two

arcuate wings

81 and 82 extending lengthwise of the

rolls

70 and 71 and having their upper ends secured as at 83 to plate 56. These wings are joined at their lower ends 84 through which extend vertical holes 85 which receive the shanks of the needles.

FIGS. 13 and 32 illustrate the structure by which the fabric shown in FIG. 4 is produced. A roll 9ft feeds a web W4 to the first set of needles 941 which produces yarnlike structures S41 on one side of the Web W4. The latter then moves to a second roll 92 and a second set of needles 94 produces yarn-like structures S42 on the opposite side of the web. The latter is then led over a roll 94 to a wind-up mechanism (not shown) similar to that shown in FIG. 8. Equal gears 86 cause the rolls to rotate as indicated and may be driven from mechanism 66 as shown in FIG. 7. The shaft 49 can be driven as indicated in FIG. 7 and drive the needles 91 very much as indicated in FIG. 9. A vertical shaft 87 is connected by equal bevel gears 85 to a driven shaft 89 similar to shaft 49 and operatively connected as indicated in FIG. 32 to the needles 93.

FIG. 18 shows how the needles of a bank can all be rotated in the same direction. Plate 95 similar to plate 56 replaces the latter and has rotatable thereon pinions 96 which mesh with gears 97 smaller in diameter than

gears

51 and 55. A central vertical shaft 98 is similar to shaft 49 and other shafts 99 are similar to shafts 54. In this way all the needles turn in the same direction as distinguished from the form shown in FIG. 11 wherein adjacent needles turn in opposite directions. The reason for providing these two types of drive for the needles will be set forth hereinafter.

The single yarn-like structures such as shown in FIG. 5 can be produced as set forth in FIG. 14 wherein the web, before reaching the feed roll 100, has been split into thin tapes or ribbons 101. A needle 102 is provided for each tape and may be mounted and operated as already described. As roll 100 and the needles 102 turn the fibers of the tapes will be gathered into coiled forms S5, but unlike the previously described forms, the yarn-like structures in this instance are separate and do not form parts of a fabric.

The needles for producing the various forms or structures S1-SS may all have the same general characteristics shown in FIG. 21. The needle shown in that figure has a straight shank 105 one end of which is adapted to fit into holding means such as the clutches 53 shown in FIG. 9. The other end of the shank is formed with the previously described barb B which as shown in FIG. 21

extends obliquely away from the shank and is pointed at 106. The barb lies preferably all on one side of the axis of the shank, projecting beyond the extended cylindrical surface or envelope of the needle shank. The base 167 of the barb is rounded at 1% to merge along a smooth curve with the part of the shank opposite to the point 106, and a second smooth curve 109 connects the base with the side of the shank adjacent to the point.

In the operation of the various forms of the invention the barbs on the needles engage fibers in various ways and have more effect on some fibers than on others. If the fibers are of a preferred random distribution in the web some of them will approach a needle parallel to the direction of feed of the web and be little affected by the needle. Other fibers may be disposed crosswise of the web feed and will be engaged either near an end or at a point more or less midway of the ends. Still other fibers will be oblique to the direction of travel and may have one end engaged by one needle and later have the other end engaged by an adjacent needle. Other fibers may not be directly engaged by any needle but will be frictionally touching a fiber that is acted on by a needle and to some extent have its position changed by the first fiber. Other fibers may be transversely disposed but not be affected by a needle. No attempt is made herein to show all possible arrangements and dispositions which the fibers can occupy as they move toward the needles as the web is drawn forwardly. A few specific fiber relations will be described but they are not by any means to be considered as anything more than representative examples.

The fibers are acted on by two forces one of which moves the web in an onward or forward direction and the other of which arises from the rotating needles and produces the coiling of the fibers. The onward feed tends to draw the coils into lengthwise helical form and the needles tend to arrange parts at least of the fibers into spiral form. Many of the fibers are therefore both helically and spirally coiled and can be stretched lengthwise due to the helical coiling and can be partly uncoiled when the fabric is stretched crosswise due to the spiral coiling. Some uncoiling can occur in the helically wound parts of the fibers incident to crosswise stretch.

In FIG. 15 a single fiber 1.10 is shown as connected to two adjacent structures S2 between which a straight part 111 of the fiber extends. The left-hand end of fiber can be considered as having been acted on by counterclockwise turning needle and the right-hand end by a clockwise turning needle, see FIG. 9. FIG. 16 shows one possible arrangement of the helically coiled parts 112 and 113 of the fiber 110.

FIG. 17 shows a fiber 1:15 disposed similarly to fiber 110 except that its structures S3 are common to the two webs which they join. FIG. 15 shows two

fibers

118 and 119 caught into the right and left-hand structures S2 respectively and extending into adjacent parts of the fabric, or to adjacent similar structures (not shown). Similarly, fibers 120 and 12.1 extend to the right and left from structures S3 in FIG. 17.

FIG. 19 is a view similar to FIG. 15 except that the yarn-like structures are produced by needles all of which turn in the same direction, see FIG. 18, and FIG. 20 is similar to FIG. 17 but with the same exception. The fiber in FIG. '19 passes from the top of one of the coiled structures down through the web to the bottom of the adjacent structure, this being true also in FIG. 20. In FIG. 19 fibers 126 are similar to

fibers

118 and 119, FIG. 15, and in FIG. 20 two fibers 127 and 128, one from the upper web and the other from the lower, are shown connected to the left-hand yarn structure S3.

FIG. 22 illustrates diagrammatically a valuable property possessed by the fabrics already described. Taking the second fabric as an example, and referring to FIGS. 15 and 16, the fabric W2 may have an original length e but because of the helical coiling shown in FIG. 16

the length can be stretched or increased to f. The original width g can be increased to the width it due to the uncoiling of the spirals shown in FIG. 15, or to uncoiling of the helices. On release of the stretching forces the helical and spiral coils will tend to return to their original forms. The fabric is thus seen to possess considerable elasticity due to the coiling of the fibers. This property is possessed by other of the fabrics, such as W3 and W4.

In the fabric W1 the yarn-like structures S1 are short and transverse of the plane of the web, but these structures S1 are spirally and helically coiled and can unwind in response to lengthwise and transverse stretching forces.

When a single web is being processed, as in FIG. 12, or when being fed by one of the drums in FIG. 10, the yarn-like structure S2 is likely to be nearer one side of the web than the other and it is for this reason that the method set forth in FIG. 13 can produce the fabric W4. FIGS. 23-26 show diagrammatically some of the forms of fabric W4 with particular reference to the direction of rotation of the needles shown in FIG. 13.

In FIG. 23 the direction of coiling for the top structures S41 is clockwise whereas for the lower structures S42 the direction is counterclockwise. The structures S41 and S42 are staggered as shown so that if the fabric is subjected to a later compressing operation the structures of the two series can nest close to or between each other.

In FIG. 24 the top series S41 is made by needles operated as in FIG. 9 whereas the bottom series is made by needles turning as for the bottom series in FIG. 23.

In FIG. 25 both top and bottom series are coiled clockwise, while in FIG. 26 both series are formed by needles which rotate in opposite directions for each series.

As already mentioned the fibers can assume a great many different positions and relations only a few of which will be described in connection with FIG. 27. In that figure a fiber 130 is shown coiled into the left-hand structure S2 and having a free end 131 which has frictional holding relation with the free end 132 of another fiber 133 coiled into the central structure S2. Another fiber 134 coiled into the left-hand structure has a free end 135 which has frictional holding relation with an uncoiled fiber 136 lying between two adjacent structures but not directly connected to either of them. .Other fibers 137 are not connected directly to any structure S2, and fiber 138 similar to fiber 110 is shown as frictionally engaged with another fiber 139 not connected to any structure S2. Other of the fabrics can have similar fiber relations.

In FIG. 23 the series of structures S41 and S42 are shown as cross connected by fibers 140 which, like others similar to them but not shown, tend to bind the two series together, the ends of fiber 140 being coiled into structures on opposite sides of the web. Similarly,

fibers

141, 142 and 143 in FIGS. 24, 25 and 26 respectively bind the structures S41 and S42 in each form to each other.

The invention has been practiced with a web containing 25% viscose fibers and 75% acetate fibers. Tests were made of samples of the web one inch wide, six inches long, and about one-quarter inch thick. The tests showed an average breaking strength of the unprocessed web samples'of 4.3 grams, whereas the processed samples containing a single lengthwise yarn-like structure, as S2, had a breaking strength averaging 23.4 grams. The coiling of the 'fibers therefore resulted in an increase of more than 500% in the strength of the web. Both the processed and unprocessed samples had in them approximately the same number of fibers.

The invention is not limited to the specific types of fibers mentioned and the fibers can be of dififerent lengths and may be either oriented, as lengthwise of the web, or placed at random.

The separate tape or ribbon webs shown in FIG. 14

8 can be out or otherwise derived from a wider web in any approved manner. One method could, for instance, be similar to the procedure set forth in American Wool Handbook, 1948, published by Textile Book Publishers, Inc., New York City, the chapter on Blending and Woolen Carding, section on Tape Condensers.

A needle which has operated successfully had a shank diameter of 0.039 inch and the point of the barb traveled in a circular path having a diameter of 0.044 inch. The length of the barb was 0.113 inch from its point to the point of merging of curve 108 with the shank. The needle was operated at 400 rpm. and the feed of the web was about two feet per minute. Other speeds of needle rotation and web feed were found to be satisfactory and types of barbs having dimensions approximating those given but of the same general shape were found to be satisfactory. The smaller the offset of the point from the shank axis the smaller will be the diameter of the yarn-like structure. The

curves

108 and 109 were honed in order to insure clearance of the structures S1S5 from the needles as the webs advanced.

While reference has been made to the spiral arrangement of parts at least of the coiled fibers, it is to be understood that the feature set forth in FIG. 22 for instance, especially the transverse stretching, can be derived from the helically wound parts of the fibers as well as any parts which may be spirally wound. Since the coil arrangement is made around a needle having an appreciable diameter the coils at one point in their formation may be hollow, but it is found that as the operation proceeds the yarn-like structures tighten on themselves so that in the finished product there is only a small axial hollow observable in the structures. Further, the barbs of the needles pick up the fibers from the web at an operating zone at the ends of the needles as suggested either in FIGS. 8, 10 or 12.

In all forms of the invention the method eifects a gathering of fibers or parts thereof drawn from a web and subjecting the gathered fibers or parts thereof to rotary action which orient them partly spirally and partly helically, and in all forms the yarn-like structures are moved away from the needles by wind-up rolls such as that shown at 74 in FIG. 8 so that the structures can clear the needles as other fibers approach the barbs. The needles are partly at least embedded in the web and the diameter of the path of rotation of the point of the barb is less than the thickness of the web. In the form shown in FIG. 1 the coil structures are shown substantially at right angles to the plane of the web but they could, if desired, be disposed at an angle by an appropriate modification of the machine shown in FIG. 6. In other forms the web at the zone of operation is moving more or less parallel to the axis of the needles and for this reason the web can be moved continuously instead of intermittently as contemplated in FIG. 6. The single web shown in FIG. 2 can be made either as suggested in FIG. 12 or by the structure shown in FIG. 10 wherein only one web will be fed over one of the drums.

The needles are preferably so mounted that their barbs do not abrade the convex rubber surfaces of the drums and when two drums are used as in FIG. 10 even a single web can be subjected to some compression as it approaches the operating zone. It is observed in operation that the fibers may gather around the part of the needle shank near the barb but they are found to slip off the shank and the barb as the web is fed forwardly. Means are provided for changing the relative speed of the needles with respect to the turning of the drums as for instance by replacing the pulleys 46 and 48 by other pulleys of different diameter which will alter the speed of the needles with respect to the rate at which the drums are turned. Another means for changing the relative speed of the needles and drums is to employ a type of reducer 66 which has a variable drive built into it.

In the foregoing the needle described is of the form shown in FIG. 21, but there are other forms of needles which can be used as shown in FIGS. 28-31. In FIG. 28 the lower end of the cylindrical shank 15b is bent laterally as at 151 and terminates in a cone 152. In FIG. 29 the lower end of the shank 155 is formed with a straight oblique surface 156 which leads to a barb or spur 157 which projects beyond the envelope of the shank 155. In FIG. 30 the shank 166 is formed with several downwardly pointed projections or spurs 161 and the lower end of the shank comes to a point 162. In FIG. 31 the shank 165 has its lower end 166 broadened by flattening and two prongs, projections, or spurs 167 and 168 are formed partly by the broadened end 166 and partly by the concave bottom 169 of the end 166.

The pointed parts of the various forms of needles may be considered as barbs, burrs, spurs, prongs or projections, but in the broader sense the needles of whatever form act due to their rotation to gather fibers into the yarn-like structures already described. The needles may in fact be formed otherwise than as shown and may be formed with a straight shank wetted with a liquid, preferably slightly adhesive, to collect the fibers as the needles turn. The needle shanks may be fluted to retain the liquid and the latter be applied to the needles in small jets.

Although the form of product shown in FIG. has been described as made from tapes or ribbons of fibers formed as such before reaching the needles, it may also be made by moving a wide web to the needles and cutting it into tapes at the needles. In fact, cutting may be omitted and reliance placed on the needles to separate the structures S5 from the web.

The guard 80 shown in FIG. serves not only to effect some compression of the web near the operating zone of the needle barbs, but also tends to arrest vibration of the barbed ends of the needles and furthermore is found to prevent fibers from climbing up the shanks of the needles. The plate .17, FIG. 6, also serves to prevent fibers from climbing up the needles.

in any of the coils shown in any of the forms described the fibers may be set in the coiled configuration by means well known in textile arts such as the heat-setting or" thermo-plastic fibers or chemical treatments which produce memory effects, thus enhancing the elastic behavior of the web system as set forth in FIG. 15.

Having now particularly described and ascertained the nature of the invention and in what manner the same is to be performed, what is claimed is:

1. The method of gathering loosely assembled fibers in a web into a spirally and helically oriented group of fibers which consists in the step of subjecting the fibers within the web progressively to continuous rotary motion to move fibers from their original positions Within the web into combined spiral and helical arrangement.

2. The method of gathering loosely assembled fibers in a web into a spirally and helically oriented group of fibers which consists in the step of subjecting the fibers within the web progressively to the action of a needle rotating around its lengthwise axis within the Web to move fibers from their original positions in the web into spirally and helically grouped arrangement.

3. The method of reenforcing a web of loosely assembled fibers consisting in the step of progressively subjecting the fibers within spaced zones of the web to continuous rotary motion to produce localized reinforcing groups of spirally and helically arranged fibers which are frictionally attached to fibers of the web between the groups.

4. The method of uniting two face to face contacting webs of loosely assembled fibers consisting in the step of subjecting the fibers in adjacent localized areas of the webs to rotary motion to produce groups of spirally arranged fibers common to the two webs and binding them together.

5. The method set forth in claim 4 wherein the rotary motion is caused by rotating needles around their length- 1% wise axes to cause barbs on the needles to enter each of the two webs as the needles rotate.

6. The method of uniting two webs of loosely assembled fibers consisting in the following steps: moving the two webs into engagement with each other along an area of contact, and subjecting spaced zones of fibers on opposite sides of said area of contact to rotary action to produce groups of coiled fibers extending into and connecting both webs.

7. The method set forth in claim 6 wherein the rotary action is produced by spaced barbed needles rotating around their lengthwise axes and the joined webs are moved in a direction away from the needles to clear the groups of fibers from the barbed ends of the needles.

8. The method of reenforcing a web of loosely assembled fibers consisting in the following steps: moving the web in a curved path, introducing barbed needles into the convex part of the web without penetrating to the concave part thereof, and rotating the needles to gather certain of the fibers into coiled groups of fibers which are connected to other coiled fibers in the web and extend in the direction in which the web moves.

9. The method of converting an elongated web of loosely assembled fibers into a yarn-like structure consisting in the step of subjecting the fibers to continuous rotary motion in a direction transverse of the length of the web to coil them in an extended yarn-like structure.

10. The method of converting an elongated web of loosely assembled fibers into a yarn-like structure consisting in the following steps: feeding the web to the nip between two rotating drums, rotating a needle in the web about an axis extending generally in the direction of feed of the Web to gather the fibers spirally and helically around said axis at the nip to form a yarn-like structure and drawing the yarn structure oil the needle.

11. The method of converting an elongated web of loosely assembled fibers into a yarn-like structure by a needle the axis of which extends generally in the direction of the length of the web and consisting in the following steps: causing the web to surround part of the needle with fibers, rota-ting said needle about its lengthwise axis to cause it to coil the fibers around it to produce a yarn-like structure, and drawing the yarn off the needle as the web is fed in said direction.

12. The method of producing a nonwoven fabric from a web of loosely assembled fibers consisting in the following steps: subjecting the fibers on one side of the web to continuous rotary action to form them into coiled yarnlike structures and thereafter subjecting the fibers on the opposite side of the web to continuous rotary action to form them into coiled yarn-like structures, thus providing a fabric having coiled structures on both sides thereof, and causing some at least of the fibers to be coiled into two yarn-like structures on opposite sides of the fabric.

13. The method set forth in claim 12 wherein the coiled structures on one side of the fabric are staggered transversely with respect to the web relatively to the coiled structures on the opposite side of the web.

14. The method of producing a nonwoven fabric from a web of loosely assembled fibers consisting in the following steps: subjecting the fibers on opposite sides of the web to continuous rotary action to form them into coiled yarn-like structure, and causing some of the fibers to be coiled into a yarn-like structure on one side of the web and extend through the web and be also coiled into a yarn-like structure on the opposite side of the web.

References Cited in the file of this patent UNITED STATES PATENTS Lundgren June 5, 1 945

Claims

1. THE METHOD OF GATHERING LOOSELY ASSEMBLED FIBERS IN A WEB INTO A SPIRALLY AND HELICALLY-ORIENTED GROUP OF FIBERS WHICH CONSISTS IN THE STEP OF SUBJECTING THE FIBERS WITHIN THE WEB PROGRESSIVELY TO CONTINUOUS ROTARY MOTION