CA1068091A - Method and apparatus for traversing a strand between two spaced rows - Google Patents

Abstract

ABSTRACT
A method of traversing a strand between two spaced rows of strand-restraining elements moving together in the same direction in the same plane to form a web is implemented by a pair of strand-restraining members associated with each row of strand-restraining elements for slideably engaging the strand and moving it in alternate traverses toward one and then the other row while forming a loop in the strand during each traverse. The loop is brought into a plane parallel to the plane of the rows of strand-restraining elements and beyond the rows. means are provided for disengaging the loop from the strand-engaging members and depositing the loop around the strand-restraining elements.

Description

10~8~191 .

Backrround of the Invention This invention relates to a method and apparatus for traversing a strand or strands to form a restrained cross-laid web. More particularly, it relates to a method adaptable to forming restrained webs of a wide variety of strand laydown patterns, and to apparatus upon which the method can be carried out at high speed.
A "restrained web" is one in which the strands which comprise the ~eb, aft~r being cross-laid in a given configuration, are held in that configuration by pins or other restraining elements until a desired operation is carried out upon the web. Additional tension may be applied to the restrained web by increasing the distance of the pins across the web after it is laid.
Many types of machines ha~e been developed for withdrawing a strand from a package and traversing it across a moving conveyor to form a web useful for rein-forcing paper or other sheet materials, or for forming scr~m or other ~abrics. The cross-laid web is fre~uently combined with a warp sheet of strands, and the two sheets may be bonded together with adhesives or othe~lise. How-ever~ most of the prior art apparatus can be operated only at relatively low speed. Many of these machines are restricted to laydown of a single ~trand, and others are incapable of forming a restrained web. Most of the prlor art machines are restricted to a particular laydown pattern, e.g., a diagonal patte m , which can be varied only to a minor extent such as by changing the spacing of the strands. In partlculnr, the achievement of a truly orthogonal laydowll has been a problem ln the prlor art.

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8~9~ ., This ls lmportant, since for many products it is desired to have re~nforcin~ strands across the width of the product at right angles to the long or machine direction of the product.
Though the term "strand" will be used through-out the specification, this term is meant to include materials such as yarn~ threads, cords, filaments and the like. Such strands may be of either natural or synthetic material. ^
Su~nary of the Invention , According to this invention a new method and apparatus have been developed for cross laying or tra-versing strands at 90 degrees or other angles to the machine direction at relatively high speed. The apparatus is one for traversing a strand between two spaced rows of ; strand-restraining elements moving together in the same direction at the same speed in the same plane to form a web. The apparatus lncludes a strand supply source, a guide located out of the plane of the rows of strand-restraining elements but ~etween the rows for receiving the strand from the supply source, and at least one pair of rotatable strand-engaging members associated with each row o~ strand-restraining elements for slidably engaging the strand between the guide and the plane of the rows and traversing the strand toward one and then the other row while forming a loop in the strand during each tra-verse. The loop is brought into a plane substantially parallel with-the plane of the rows and extended beyond the rows and ls then disengased from the strand-engaging members and deposlted about ~t least one of the strand-.;. ~ .

_ 3 _ -~ 9 restraining elements, The method involves not only forming a loop in the strand in the plane of traverse but turning the loop out of the plane Or tra~erse into a plane su~stantially parallel wit~ the plane of the strand-restraining elements and then depositing the loop thus oriented onto at least . one of the strand-restraining elements to form a restrained cross-laid web.
Brief Description of the Illustrated Efflbodiments _ Fig. l is a front elevation of the apparatus for traversing strahds according to the present invention, Fig. 2 is a top view of the apparatus shown in.
Fig. l.
Fig. 3 is a partially sectioned vlew of the apparatus shown in Fig. l taken along 3-3.
Fig. 4 is a perspective view showing the rela-tionship of hooks and spreaders on the rotating disks for traversing two strands onto the pin conveyor.
Fig. 5 is a view taken along 5-5 of Flg. 4.
20 Fig. 6 is a view taken along 6-6 of Fig. 1~.
Flg. 7 is a view taken alon~ 7-7 of Fig. 4.
. Fig. 8 is a perspective view of another rela-; tionship o,f hooks and spreaders on rotating disks driven together for traversing a single strand onto the pin ~' conveyor.
'f Fig. 9 is a view taken along 9-9 of Fig. 8.
Fig. 10 is a view taken along lO-10 of Fig. 8.
Fig. ll is a view taken along ll-ll of Fig. 8. :~
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Fi~. 12 shows a typical pattern of a single~
- 30 strand restrained web havin~ parallel, dia~onal courses ~0Ç~8~9~
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iormed by traversing the strand between the rows of strand-restrainlng pins.
Figo 13 shows a single-strand restrained web ln which all the courses are parallel and orthogonal to the long direction o~ the web.
Fig. 14 shows a restrained web like the one in Fig. 13, including details of spacing pins for achieving - a pattexn in which ad~acent courses of the web are truly ~-parallel. -Fig. 15 shows a single-strand restrained web in which the courses of the web have V-shaped re~ersals at each side, only the alternate courses of the web being parallel.
Fig. 16 shows a two-strand restrained web having a patte m in which all courses are parallel and are orthogonal to the long direction of the ~reb. ~ ~-Fig. 17 sho~s a two-strand restrained web having `
a pattern in which all courses of the web are parallel and are diagonal to the long direction of the web.
Fig. 18 shows a two-strand restralned web having diagonal courses with V-shaped reversals at each side of the web. -~
Detailed Description of the Illustrated Embodiments Referring to Figs. l-3, a suitable framework is indicated comprising bottom ~rame 20 and two upri~ht frames 22, 24 moun~ed to the ~ottom frame. Positively;~
driven pr~lary disks 26 and 28 are mounted on sharts 27 `
and 29, respectively, for rotation, in the directions shown by the arrows, in ~earlngs mounted on ~rame 22. In a slmilar manner po~itively driven secondary disks 30, 32 ~ .

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10~8091 are mounted in a skewed relationship to the primary disks on respectlve shafts 31 and 33 for rotation, in the direc-tion of the arrows, in bearings mounted on frame 24. Posi-tioned midway between disks 26, 28 is a dual-eyelet guide ; 34 for receiving strands 36 as they come (preferably after passing through a tension gate~ not shown) from supply packages 38 mounted on creel 39, which is so positioned that the strands move freely to and through the eyelets of the guide. The eyelets may be provided with slits to facilitate string up.
Primary disks 26, 28 carry yarn hooks 40 attached at five equal spacings on their peripheries and extending outward from these disks. Each of the hooks 40 comprises an arm with an end projecting at right angles to the arm and there are slots formed in this end with the same spacing -~ as the eyelets in guide 34. The plane of disk rotation is such as to align the slots with the eyelets in guide 34.
The ælots may be formed in a number of ways, e.g.~ by groov-ing the projecting end of the arm or by inserting pins therein.
Secondary disks 30, 32 carry spreader arms 61 attached at four equal spacings on their peripheries and ex-tending outward from these disks. The relative speed of rotation of the primary and secondary disks is such that hooks and spreaders always pass by guide 34 ln the same position relative to each other. Each spreader arm 61 has fingers extending outward from the arm with spacings between the ,, , :
fingers that match the spacings of the eyelets in guide 34.
The path of spreader rotation is such that the fineers ~ust clear guide 34 as they pass by. The interrelationship between the fingers on arms 61, the slots in hooks 40, and the eyelets '' .

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in guide 34 ~ill be described in morc detail later.
Mounted below the disks in frame 20 are a pair of endless driven conveyors 50, 51. The conveyor 50 is mounted on pulleyG 52, 54 and conveyor 51 is similarly mounted on pulleys (not sho~m). Pulley 52 and its counter-part for conveyor 51 are mounted on a~le 56 which is mounted for rotation in bearings mounted on one end of the frame 20, and pulley 54 and its counterpart for con-veyor 51 are mounted on axle 57 mounted for rotation in bearings mounted at the other end of frame 20. Both con-veyors move together at the same rate of speed in the direction of the arrows sho~ . Mounted on the surface of both conveyors are upstandin~ pins 5~ for restraining the `
strands. m e pins in each row are arranged with the spacing required to obtain the desired web pattern, and the conveyors are moved together in such a way that the proper relationship of pins in each conveyor with respect ~-to the other is maintained.
Doff blades 65, 66 are rotatably mounted on driven shaft 67 in bearings mounted on ~rame 20, These blades are rotated in vertical planes that are close to ; but outside the paths of conveyors 50, 51. The blades preferably have notches that match the positions of the slots in hooks 40 as the blades rotate past the hooks.
The blades may also have notches that matcll the positions of the spaces between fin~ers in spreader arms 61.
Synchronization of the blades 65, 66 is such that each blade passes between an a~n 61 and conveyor 50 or 51 shortly after arm 61 passes over the conveyor. The blades travel at a hi~her velocity t~lan the velocity o~ the arms, ~
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the blades pre~erably being given five to fi~teen rotatlons for each rotation of primary disks 26~ 28.
Although all the various motors, pulleys, belts or like mechanical means have not been completely illustrated in the drawings or completely described in the specification ~or driving or supporting the various rotating disks and conveyors in their desired or required speeds or with the rotation indicated by the direction arrows, it is to be appreciated that such elements and descriptions have been omit~ed to keep the drawings and the description succinct and to avoid the introduction o~ matters which are well known expedients in the art. The mechanical driving means and various ~rames which are used are conventional and merely involve the application of well known mechanical principles.
, Referring now to Figs. 4-7, the operation of the hooks 40, the spreader arms 61 on the rotating disks along ,~ with the endless conveyors 50, 51 and their respective doffing blades 65, 66 provides the means for slideably en-gaging the strands and traversing them toward one and then the other row of pins 59 on each conveyor. A loop in each strand is formed during each traverse and then the loop is brought into a plane substantially parallel to the plane of the conveyors before bein~ disengaged from the hooks and spreaders and then deposited around pins 59 on the respective conveyors to form an ortho~onal web 37 movlng in machine direction L. More particularly, Fi~. 4 shows two strands ; 36 being fed from a source of supply to the eyelets of gulde 34 located above the plane of the conveyors 50, 51 and each strand is thence led toward and beyond conveyor 51 by the hook 40 on primary disk 28 in a traversine plane which '' "`

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10~80~31 contains its respectlve eyelet in euide 34 and ls transverse to the plane of the conveyors. As the strands are led toward conveyor 51 they are lntercepted and slideably engaged by a hook 40a on pr~mary disk 26 at a location between conveyor 51 and guide 34 and each strand is thereupon led by a first point of sl~ding engagement on hook 40a through an arc in the traversing plane towards conveyor 50. As the strands are led toward conveyor 50 the fingers of spreader arm 61a move down between the strands and across the traversing plane of each strand to intercept each strand in a second point of sliding engagement. This ~ction is caused by mounting the primary -and secondary disks so that, in the vicinity of the inter-~ection o~ the planes o~ the two disks, the tips of the 6preader fingers are farther away from the center of the primary disk than the hooks are. Thus, the strands are led -` by spreader arm 61a still towards conveyor 50 but also away from the traversin~ plane in a direction opposite the motion of the conveyors through an arc in the skew plane of second-ary disk 30, said skew plane intersecting both the travers-ing plane and the conveyor plane.
While the strands are being led towards conveyor 50 after being intercepted by hook 40a and then spreader arm 61a, each strand is formed as an open loop, with one corner o~ the loop moving ln the traversing plane and one corner mov-lng in the skew plane. Each loop is led beyond the conveyor 50 whereupon the strands are intercepted by do~f blade 65 slideably engaged around the pins 59 of conveyor 50. To show this clearly, locations 5-5, 6-6 and 7-7 on Fig. 4 are presented as enlar~ed views (Figs. 5, 6, 7) of the relation-ship o~ the strands, hook and spreader duri~g the traverse ;...................................................................... ~
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through those locations. Referring now to Fig. 5, eachhook 40a has an end 42 projecting at a right angle and there are slots 43 in the end 42 with the same spacing as the eyelet in guide 34 and each spreader arm 61a has at its extreme end fingers 63 which extend outward from the arms and also form spacings 64 which match the spacing of the eyelets in guide 34. The fingers 63 have engaged strands 36 and are leading them towards the conveyor 50 but away ~rom the traversing plane. In Fig. 6, taken at location 6-6 of Fig. 4, the open loops are shown being formed and in Fig. 7 this is shown more clearly wherein the strands 36 have been led by two sliding points of engagement, one on each slot of the hook 40a and one on each finger of the ;~
spreader arm 61a in the form of open loops beyond the con-veyor 50. Each loop consists o~ three sections, a side ~ection 36a between the guide 34 and the spreader arm 61a, an end section 36b between the two sliding points of engage-ment on the spreader arm and the hook and side section 36c between the ho~k 40a and conveyor 51. The loop is moved to the conveyor plane by the action o~ do~f blade 65 so that the side sections 36a and 36c are deposited ln intervals between pins 59 on conveyor 50, the end section 36b of the loop bridges a designated n~nber of pins. All of the slide-able engaging points holding both loops are disengaged from the strands during the depositlon of the loops.
Figs. 8-11 represent an alternate embodiment with four hooks and spreader arms placed at equal spacing around the periphery of each pr~nary and secondary disk.
These disks as with the preferred embodlment are in a skewed relationship with each other, however, companion ..

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~8091 primary and secondary disks (26' and 30~; 2~ and 32') are driven together ~or traversine a single strand onto the pin conveyors. Similar elements have been eiven the same numbers only the numbers have been primed.
Conveyors 50', 51' comprising t~ro rows of strand-restralnlng elements (i.e., pins 59'~ which are parallel to and spaced apart from one another, defining a conveyor plane, are moved longitudinally in the same direction in the conveyor plane.
A strand 36' is fed from a source of supply 38' to a forwardin~ point (guide 34') located midway between the two rows and at a distance from the conveyor plane, and the strand is thence led to~ards one o~ the rows (conveyor 51') in a traversing plane which contains -the ~oruardin~ point and is transverse to the conveyor plane, intercepting both conveyors.
As the strand is led towards one of the rows (conveyor 51'), it is intercepted and slideably engaged -: by hook 40a' between that row and the guide 34 ', and the ;
strand is thereupon led by a first slidin~ point of engagement on hook 40_' throu~h an arc in the traversin~
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plane towards the other row (conveyor 50', Fig. 8).
As tlle strand is led toward conveyor 50' it is intercepted a~ain between the rorwarding point (guide 341 ) and the first slic~ine point o~ en~agement on hook 40a' by spreader 61a' (Fig. 9) and is then led by a second sliding point Or en~a~ement on spreader 61a', still towards the other row but also away from the traversing plane in a direction :~ .
opposite the direction o~ motion of the con~eyors 50', 51', through an ~rc in a slcew plane, sald skew plane intersectine ' . `

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While the strand is being led towards the other row (conveyor 50') after the two interceptions, it is being held in an open loop ~hairpin loop) having three sections: a side section 36a' between the fo~qarding point and the second sliding point o~ engagement, an end section 36b' between the two sliding points of engage-ment, and a side section 36c' between the hoolc 40a' and conveyor 51'.
The strand is led by the two sliding points of engagment in the form of the open loop beyond the other row o~ strand-restrainlng elements, whereupon the strand is intercepted by doffing blade 65~ (~ig. 11) and slideably engaged upon each side section of the loop at points near the conveyor and moved to the conveyor plane, so that the side sections of the loop are depo~ited within intervals be-tween the strand-restraining elements~ the end section of the loop bridging a designated n~nber of intervals between strand-restraining elements. All o~ the slideable engaging points are disengaged from the strand during the deposition of the loop.
Fig. 12 illustrates a typi~al web pattern o~-tained by traversing a single strand 36' around the pins 59' in the manner sho~m in Fig. 8, the completed web mov- ` -ing in the lon~ or machine direction of the web as sho~m by the arrow L parallel to the center line o~ each row of .. . .
pins. The completed web is restrained by the pins, whicl hold pin~contactin~ se~ments of the strand. ~s shown in more detail in Fi~. 14, the pin contactlng segments 104 are defined ~y t~ngent points 105 at the outermost point ~-',~

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of each pin, and 106, on or near the center line of the row of pins. In addition to the pin-contacting segments, the web comprises courses 107 lying between tangent points 106 at opposite sides of the conveyor and selvage segments 108 parallel to web direction L lying outside the rows of pins between tangent poin~s 105. With respect to the cross direction C of the web, normal to L, and with respect to the forward direction of the web, adjacent courses are laid down at angles aL and aR from the left and right sidés of the conveyor (Fig. 12), respecti~ely. The effective strand directlon during the strand laydown is shown by arrow SL for angle aL and by arrow SR for angle aR. In the pattern specifically shown in Fig. 12, each course is laid do~ parallel to the previously laid do~m course, -~ .
æo that aL = ~aR- The loop fo~ned in the strand during each traverse as the web is laid down is sufficiently wide to be deposited around two pins at each side of the conveyor, the end of the loop on the supply side of the strand being one end of the next course to be laid down.
Fig. 13 represents the special situation in which aL = aR = - Each course o~ the web is orthogonal to the long direction of the web, the strand ~eing laid down at right angles to the direction of the motion of the conveyor. All courses are parallel to one another.
In order for each course o~ the web to be truly parallel to the precedin~ course, as in the web patterns of Figs. 12 and 13, each end of each course (tan~ent point 10~) must ~e equally spaced in the lon~ direction of the web from each end of ~he precedin~ course. ~ first 30 requixement ~or achievin~ such parallellsm is ~ pin ~~

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10~91 arrangement in which the pins on each slde o~ the con~
veyor nre arranged in identlcal spaclng patterns, the pins in each row bein~ positioned for equal spacing of the tan~ent points 106 at which the courses contact the pins (rather than equal center-to-center spacing of the pins). Fig. 14 shows a suitable pin arrangement for obtaining the web laydown pattern shown in Fig. 13. Each row of pins comprises pairs of pins of diameter d having centers spaced apart by distance D, the center of each 10 pin in each of such pairs being separated in the direc-tion away from the other by a distance D ~ 2d from the center of the nearest pin of the next pair in the same row. The ends 106 o~ adjacent courses are thereby equally spaced from one another on each side in the long direction of the web, the spacing being the distance D ~ d in the arrangement shoun in Fig. 14. The patterns of the two rows are offset with respect to one another such that each pair of pins (separated by center-to-center pin spacing of D) is positioned opposite a gap having a center-to-center pin spacin~ of D ~ 2d on the other side, ~hich positions the courses ortho~onal to the long direction of the web. For diagonal laydown Or patterns with true parallelism o~ ad~acent courses~ such as shown in Fig. 12, the appropriate positionin~ o~ pairs of pins on one side of the conveyor with respcct to the pairs of pins on the other side is the same as the posi~
tionin~ employed for the correspondin~ ortho~onal pattern, except that the pairs of pins on the right side are orfset b~ an~le aL from the correspondin~ gap on the other side.
3o In the precedln~ discussion the strnnd dlameter has been -' ~' .~ , .
_ 14 -... r, -- - -- : - -10~8091 treated as ne~ligible. For more precise parallellsm, and especially ~hen the strand di~neter ls not negligi-ble, the pin spacing should be arranged for equal spacing of the center points of the strands in adJacent courses.
In addition to pin spacing, factors controlling the laydown pattern for each strand include the direc-tions in which the strand is traversed from left to right and rrom right to left, the direction of loop formation with respect to the direction of web laydown, and the 10 speed of the conveyor with respect to the rate of strand i~
deposition along thé selvage. In setting up the apparatus ~..
to lay down a ~reb pattern in which aL = -~R (including aL = aR = ), the primary hooks are pre~erably mounted ~-to rotate in the same plane on each side of the guide.
During each traverse o~ the strand a loop is ~ormed which can be readily deposited around the strand- -restrainin~ elements, e.g., a pin or pins. m e loop needs to be of sufficient width to span the targeted pins or other strand-restraining elements in their entirety so that deposition can be completed e~ectively, but should be only slightly wider than the maximum distance to be spanned; othe~ise, strand deposition is Jerky because the loop collapses under tension until it is restrained The normal manner ~or ~orming loops is to ~onn them in the direction away from the direction in which the completed web is moving, i,e , in the direction away ~rom the co~lrse which has just been laid down. Formin~ the loops in this normal manner is a second requirement for lnyinlr down each course o~ the we~ truly parallel to the precedin3 course.
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` 30 The conveyor carryin~ the rows o~ pins can ~e : . _ .
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ad~usted to opcr~te at any desired speed. The rate of travel of the pins is thus independent of the rate at which loops are generated and laid do~ to form selvage segments. Accordingly, a third requirement for laying ; down each course truly parallel to the preceding course is ~hat the distance traveled by the conveyor per unit of time be set equal to the total distance between courses of a single strand laid down per unit of time.
In forming the patte m of Fig. 15, the pins are equally spaced along each row in staggered relationship to the pins on the opposite side of the conveyor. The strand is laid down during each traverse at an angle to L, in the direction ~way from the course ~hich has just been laid do~, but during each traverse only a small loop ls formed, the size of the loop bein~ suita~le Lor de-position about a single pin. The conveyor is operated at a speed sufficient that adjacent courses are laid doT~ at the desired angles aL = aR f negative sign. In this lay-do~. pattern the strand thus makes essentially a V-shaped re~ersal, the pin-contactin~ segments of the s~rand oeing in contact with a~nost half the circumference of each pin. This web pattern contains no selva~e section OL the strand parallel to the rows of pins between courses.
Fig. 16 illustrates the web pattern obtained by traversing two strands, 108 (solid line) and 109 (line ; ~
of dashes), in the manner sho~n in Fig. 4. To show the paths of each of the strands alons the selva~e more clearly, one of the strands is shown spaced nway from the pins, although both of the strands are actually in contact ~; 3 with the p~ns around which they are traversed, In the . ., .~ .

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10tj8091 - s restrained web so obtained, all courses are orthogonal to the long direction of the web. The loops formed during traverse span three pins (more generally, n + 1 pins are spanned by each loop when n strands are traversed). For each strand the pins are spaced in a manner analogous to that shown in Fig. 14 (using a relatively large value for D), the pins for the other strand being inserted in each row in positions providing equal distances between the ~-courses in the web. In this pattern ~L ~ ~R =
Fig. 17 illustrates the web pattern obtained by ;
traversing two strands 111, 112 in a manner analogous to that employed in Fig. 12 for a single strand. In -the restrained web so obtained all courses are parallel to one another in the same diagonal direction between the two rows of pins. The loops formed during each traverse span three -pins, only the first pin and the third pin being utilized for restraining any given strand. In this pattern ~L =
~R-Fig. 18 illustrates the web pattern obtained by : ~.
traversing two strands (108' and 109') in a manner analo-gous to that employed in Fig. 15 for a single strand. Dur-ing each traverse of each strand a small loop is formed and deposited around a single pin. The two strands are traversed together, each being deposited at the end of each traverse around the second pin in the row from the las-t pin on the ~7 same side restraining the same strand. The web is charac-; terized in appearance as an array of diamond-shaped patterns.
In this pattern aL ~ ~R (both of negative sign).
Webs formed by the method and apparatus of this invention may be employed for any of the purposes described .:
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in the prior art for cross-laid webs.
In the apparatus oE the invention the operations of traversing and depositing the strands are advantage- -ously carried out with mechanical components which move in simple rotary pa-ths. Web formation at strand feed speeds in excess of 1000 yards per minute is readily obtained.
Although four hooks and four spreaders are shown on the disks of Fig. 8 and five hooks and four spreaders on the disks of Fig. 4 other combinations of hooks and spreaders are possible. When more than one strand is tra-versed, it is preferred to have fewer spreaders than hooks.
It is also preferred to engage the strand with a hook on ;~
one side prior to deposition of a loop on the other side of the eonveyor.
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Claims (10)

What is claimed is:

1. An apparatus for traversing a strand between two spaced rows of strand-restraining elements moving together in the same direction at the same speed in the same plane to form a web, said apparatus compris-ing:
a strand supply source;
a guide located out of the plane of said rows and between them for receiving the strand from said supply source;
at least one pair of rotatable strand-engaging members associated with each row of strand-restraining elements for slideably engaging the strand between said guide and said plane and traversing said strand toward one and then the other row while forming a loop in said strand during each traverse and bringing said loop into a plane substantially parallel to the plane of the rows of strand-restraining elements and beyond said rows; and means for disengaging said loop from said strand-engaging members beyond said rows of strand-restraining elements and depositing the strand in a loop around at least one of said elements,

2. The apparatus of claim 1, each one of said pair being mounted for separate rotation on different centers and in different planes, said different planes being skewed with respect to each other.

3. The apparatus of claim 1, said guide being a bar with a plurality of eyelets therein, one of the pair of said strand-engaging members being a hook with slots therein, there being the same number of slots in each hook as eyelets in said bar.

4. The apparatus of claim 1, said means for disengaging said loop from said members being a blade located outboard of each row and synchronously rotated with respect to said strand-engaging members and said rows through a circular path extending above and below said rows.

5. A method for traversing a strand between two spaced rows of strand-restraining elements moving together in the same direction in the same plane to form a web, each traverse comprising:
feeding the strand from a supply to a location out of the plane of the rows of strand-restraining elements and between them, and thence toward one of the rows;
engaging the strand between said location and said strand-restraining elements and moving the strand toward the other row of strand-restraining elements in a transverse plane angled to the plane of the strand-restraining elements while simultaneously moving the strand away from said transverse plane to form a loop in the strand;
bringing said loop into a plane substan-tially parallel to the plane of the strand-restraining elements; and depositing said loop on said other row of strand-restraining elements.

6. The method as defined in claim 5, said transverse plane being orthogonal with respect to said rows.

7. The method as defined in claim 5, said transverse plane being diagonal with respect to said rows.

8. The method as defined in claim 5, said transverse plane being perpendicular to the plane in which the strand-restraining elements are moving.

9. The method as defined in claim 5, said strand being moved toward the other row of strand-restraining elements in an arcuate path.

10. In a method of traversing a strand between two spaced rows of strand-restraining elements moving together in the same direction in the same plane to form a web, wherein said strand is fed from a supply between the rows towards one row and is traversed in a plane transverse to the plane of the strand-restraining elements toward the other row, a loop being formed in the strand during each traverse;
the improvement comprising: turning the loop out of the plane of traverse into a plane sub-stantially parallel to the plane of the strand-restraining elements; and then depositing it on said other row of strand-restraining elements.