US2541745A - Method of and apparatus for weaving leno fabric - Google Patents

Description

Feb. 13, 1951 H. .1. CARRAGHER METHOD OF AND APPARATUS FOR WEAVING LENO FABRIC 15 Sheets- Sheet 1 Filed Sept. 5, .1947

Feb. 13, 1951 J CARRAGHER 2,541,745

I METHOD OF AND APPARATUS FOR WEAVING LENO FABRIC Filed Sept. 5, .1947 I I5 Sheets-Sheet 2 Feb. 13, 1951 H. J. -CAR RAGHER 2,541,745

METHOD OF AND APPARATUS FOR WEAVING LENO. FABRIC Filed Sept. 5, .1947 .5 Sheets-Sheet 3 [MeraZar fizzy/ad 6W7; er 9% i 0 W5.

Feb. 13, 1951 J, CARRAGHER 2,541,745

METHOD OF AND APPARATUS FOR WEAVING LENO FABRIC Filed Sept. 5, .1947 '5 Sheets-Sheet 4 Feb. 13, 1951 H. J. CARRAGHER k5 Sheets-Sheet 5 2 M w W 7 p w p METHOD OF AND APPARATUS FOR WEAVING LENO FABRIC Filed Se t. 5, .1947

Patented Feb. 13, 1951 METHOD OF ANIi APPARATUS FOR W'EAVING LENO FABRIC Hugh- J. Carragher, Danielson, Conn assignor to Powdrcll & Alexander, Inc., Danielson, ConrL, a corporation of Massachusetts Application September 5, 1947,. Serial No. 772,434

15 Claims.

, 1 This invention relates to improvements in method and apparatus for lenoweaving, including the weaving of figured fabrics in which leno weaving is alternated with another type or types of weaving.

Principal objects of the invention are to reduce thread breakage; to facilitate setting upthe loom; to simplify securing proper tension on the warp threads; to equalize warp tension at successive picks in weaving; and generally to allow use of a lower maximum tension than has heretofore ordinarily been practicable. A further advantageous feature of the invention is that it helps to avoidv so-called tracking or pairing of the picks. Another advantage is in saving in operating power.

As is well known in leno weaving, so-called standard or ground warp threads and so-called doup warp threads are crossed by douping mechanism, and a shed formed of the crossed threads so that the pick of the shuttle binds such crossing into the web. Various forms of douping mechanism may be employed in crossing the doup threads and the standard threads. For simplicity, the invention will be described as employing douping mechanism operating in the general manner of that of United States Patent Nos.

1,037,150; 1,037,151; and 2,040,791 in whichv the .doup threads are controlled by doup needles which are operatedby harness-actuated lifting 'heddles as described in said patents, all of the doup threads being guided on their way from the warp beam tothe doup needle edges by passing beneath a so-called dead rod or dancing bar, while the standard threads are controlled by harness-actuated heddles, which may be referred :to-as standard heddles or ground h-eddles, located at the rear of such doup needles. In operation, movement of the doup thread to the right with relation to its corresponding standard thread when opening the shed may be termed douping to the right, and movement of the doup thread to the left with relation to its corresponding standard thread when opening the shed may be termeddouping tothe left." In the following discussion the terr'n's'fleft and right will be taken to meanleft andright of the weaverv as hefaces the breast beam. For simplicity indescription, only one row of doup needles and their associated harnesses is here illustrated.

Herein when reference is made to figure or fancy weaving it is intended thereby to designate such material as figured niarquisette which is a combination of plainweaving with cross or'leno weaving. The term plain weaving is herev used for convenience 'todesignate a weave (whatever the pattern in which each warp is always dis- For figure weaving. it is customary to provide a bank of standard harnesses and to draw in the standard threads in accordance with some predetermined pattern, and provision is made for automatically suspending the douping action and imparting a full shedding action to some or all of the standard harnesses while the doup thread remains idle.

While certain features of my invention are of utility in leno looms having a single harness of standard heddles, added advantages result from incorporation of the invention in leno looms having a plurality of such harnesses. Thus such plurality of harnesses are neededto accommodate the necessary number of heddles. for fine weaving,v and. more especially, as above suggested, to give selective control of. groups ofthese heddles in weaving-a patternfduring suspension of leno weaving. Therefore, the invention will be explained as incorporated. in aleno loom having a plurality of rows of harnesses of standardv heddles, some, at least, ofwhich cooperate with the doup needles in leno weaving but which. act alone to weave plain fabric during-suspension of leno 25 weavi g Especially in'leno looms of this type difiiculties have long been encountered due to the different effects. which are produced in douping to the two different sides of the standard thread, and, al-

though eiforts have been made to minimize such differences, the difficulty has remained and constitutes a source of great inconvenience.

In customary leno weaving procedure, when a doup thread is passed to one side of its corresponding standard thread (in the present disclosure the right side), a so-called slack shed. is formed, and when the doup thread is passed to the opposite .side (here the left side) of its standard thread, a so-called tight shed is formed. Obviously it would be desirable if the doup threads could be tensioned to the same degree whenever the leno shed is open, whether the doup thread has been raised at the right or left of its associated standard thread, thus avoiding the alternate tight and slack sheds.

, Customarily the cooperating doup and stand,-

ard threads of a pair aredisposed in side-by-side relation (in parallel vertical planes) at thelocation ofthe heddle eye through which the stand ard thread passes. Assuming that in the closed shed the doup threadis at theright (as the weav,

er faces the loom) of the associated standard thread, then in douping to the right the doup thread merely rises .in its own vertical plane. However, in douping to theleft, the doup thread must first be crossed. horizontally to the left below the. standardthread and then raised. Thus, douping to the left requires a greater length of thread than douping to the right; consequently,

the doup thread is differently tensioned at successive picks. As a result, the shed formedin douping to the right is looser (slack shed) than when douping to the left (tight shed).

At each opening of the shed, in leno weaving, a standard and doup thread of a, pair diverge rearWardly-from the fell of the cloth, and, as viewed from the side of the loom (although they may not actually touch each other), appear, when so viewed against a vertical plane, to make an acute angle with one another. At the rear of the open leno shed the standard and doup threads diverge forwardly, and when similarly viewed (although they may not actually touch) appear to make an acute angle with each other in the vertical plane. Hereinafter, for convenience in description, these apparent angles, as seen against a vertical plane, will be referred to as the front and rear shed-angles, respectively. The present invention is particularly concerned with preventing the apex of the rear shed-angle from approaching too closely to the heddle through whose eye passes the standard thread of a given pair, especially those heddles nearest to the doup needles.

In customary leno looms the paths of a cooperating pair of doup and standard threads are such that the apex of the rear shed-angle, induced by the douping, may occur to the rear of the heddle of the corresponding standard thread when forming the slack shed, but in forming the tight shed the apex of the rear shed-angle can 'no longer occur at such location but only forwardly of the heddle eye which carries the corresponding standard thread, the threads mutually restraining each other in vertical planes, in front of the heddle. The doup thread thus urges the standard thread to a less open shed position, and the standard thread tends to pull the doup thread down so that the run of doup thread, extending to the doup needle eye, makesa less acute angle with the run of standard thread which extends forwardly to the fell of the cloth than during the formation of the slack shed.

The mutual deflection of one thread by the other in forming the tight shed involves a bending of each thread around the other and consequent increased tension and friction in forming the tight shed. This effect is increased by the fact that the threads attain a mutually dethreads. When successive crossings are tight and loose, then each newly beaten-in tight crossing tends to transfer its tension to the next loose crossing, which tends to cause each tight pick, that is each pick woven through a tight shed, to back off away from the preceding pick, causing the filling threads in the woven fabric to appear in pairs rather than equally spaced.

In an effort to equalize the tension between the tight shed and the slack shed, it is customary to allow the tight shed to be smaller than the slack shed, for instance, by not raising the doup threads as high in forming the tight shed as in forming the slack shed, thus decreasing to some extent the displacement of the doup threads in forming the tight shed as compared to the slack shed. However, this expedient introduces the difliculty that the smaller tight shed tends to squeeze the shuttle, increasing danger of thread breakage, and also, by the friction between the warps and the shuttle, increasing the power consumption of the loom.

Moreover, the tensions can not be fully equalized merely by allowing the tight shed to be smaller than the slack shed because in forming the tight shed the doup threads, as they chafe by the standard threads, tend to raise these standard threads and so reduce the size of the shed, this type of reduction in the size of the shed not being accompanied by reduction in the doup thread tension but, on the contrary, tending to,

increase the tensions of both the doup and ground threads.

In ordinary plain or one-and-one weaving, alternate threads of the warp shed first form the upper and then the lower wall of the open shed. In contrast with this, in plain leno weaving, alternate warp threads (for example the doup threads) always form the same shed wall (usually the top wall), while the intervening warp threads (standard warps) always form the other wall of the shed (usually the bottom wall). 7 Furthermore, in plain leno weaving, it is customary to place both doup and standard threads in the closed-shed position at the instant of A douping in order to facilitate the crossing of the .flecting relation before the shed is fully opened and thereafter saw past one another as the shed .continues to open.

Modern standard heddles used in leno weaving consist essentially of vertical, generally fiat metal strips which lie in planes generally parallel to the direction of the warp. When the doup thread is crossed, in usual prior fashion, with the stand- ,ard thread in the formation of the tight shed, the doup thread can readily jam in between the flat surface of the heddle and the portion of standard thread which has just emerged from the heddle eye, the restraint exerted by the standard thread upon the doup thread tending to hold the doup thread in this jammed condition. Objectionable chafing of the thread thus occurs at the standard heddles, this chafing condoup threads beneath the standard threads and at the same time to avoid excessive lift of the doup threads. To insure a sufilciently open shed, the standard threads are moved downwardly from the closed'shed or mid-position as the shed is opened, the standard thread harness being given a half-shedding motion by the dobby mechamsm.

Since the standard threads thus move away from the mid-position as the shed opens it is necessary to locate the dead rod (around which all of the doup threads pass) so that it will not interfere with the motion of the standard threads.

In a loom designed to weave plain leno only it is sometimes possible so to'locate the dead rod immediately to the rear of the standard heddles (and not far below themid-plane of the warp sheet), and thus the run of doup. thread, extending forwardly from the dead rod to the doup needle eye, inclines upwardly and forwardly with a relatively slight slope and consequently makes an obtuse angle with the forward run of the doup thread extending fromthe doup needle eye. However, when the loom is designed for weavin fig.- ured fabrics (including plain weaving as well as leno weaving) which necessitates the provisionof a substantial number. of standard harnesses with provision for moving these harnessesboth upand down (and usually to a greater extent than is necessary inleno weaving), the location of the dead rod, so that it will not interfere with the standard threads during plain weaving, and where it will insure an acceptable upward slope of the run of doup thread leading toward the doup needle eye in the open shed, becomes a matter of substantial difficulty. For this class of weaving a bankof twelve or more harnesses is not un'- common. Such a bank of harnesses occupies a very substantial space (from front to rear) in the loom so that in a loomusing the usual standard thread heddles, it is no longer possible to locate the dead rod at the most desirable position. The dead rod is necessary as a guide'for the doup threads and to help to maintain the tension on the doup threads in the closed shed position.

In the embodiment of the invention herein chosen for illustration,- the doup needles are attached to their actuating rods below the shedding point, being known as bottom doups. However, it is to be understood that the invention is equally applicable to apparatus of' the kind in which the doup needles are attached to their actuating rods above the shed line and known as top doups.

Thus, although for convenience in description use is herein made of such expressions as up and fdown in describing the motion of certain parts, it is to be understood that these expressions as so used, apply specifically to the embodiment actually shown, and are not to be regarded as limiting the application of the invention.

As indicated above, the present invention aims avoid the various disadvantages described above. More particularly the invention aims to reduce and equalize thread tensions and to enable the two open leno sheds to be of substantially the same size and shape and to be formed with equal facility in a leno loom designed for figure weav ing, and to enable the loom to be set up for operation with the minimum of effort.

U Other and further objects and advantages of the invention will be pointed out in the annexed specification and by reference to the accompanying drawings wherein Fig. 1 is a more or less diagrammatic elevation of a leno loom embodying the present invention,- designedfor figure weaving and, viewed from the right-hand side of the loom, indicating the positions of the lay, the doup needle harness, a plurality of standard harnesses and the dead rod, withthe parts positioned as they appear after the" shed has been opened in douping to the left;

Fig. 2 is a view generally similar to Fig. 1 but omitting some of the parts and showing the loom when the leno shed is closed;

Fig.- 3 is a diagram, omitting many of the parts shown in Fig. 1, but illustrating the general shape and location of the shed formed in douping to the right in leno weaving, in accordance with the present invention;

Fig. 4 is a diagram generally similar to Fig. 3 but illustrating the shape and location of the shed formed in douping to the left in leno weaving, in accordance with the present invention;

Fig. 5 is 'a view illustrating a common shape of shed formed in douping to the left in a leno loom of the customary prior construction;

Fig. 6 is a similar view showing a commonshape' of shed formed in douping to the right in the or-' dinary leno loom Fig. 7 is a side elevation of a doup needle of a standard type such as may be used in the prac tice of the present invention;-

' Fig. 8 is a view generally similar to Fig. 1 but Phowingtheparts arrangedzror plai n weaving;

6 with the doup needles in the c1osed-shed position, and with the standard heddles arranged in op'en' shed position; and

Fig. 9 is a fragmentary section through a piece of leno fabric, illustrating the way in which the weft picks interlock with the standard and doup warps.

Although various forms of mechanism may be used to pass the doup threads on alternating sides of the ground threads and to carry the doup threads to open-shed position, the invention is, as indicated above, illustrated as employing doup heddle mechanism having the general construc tion of those of United States Patents Nos. 1,037,150; 1,037,151; and 2,040,791. The construetioh of this mechanism will not be described indetail because it is well known in the art, and the aforesaid patents may be referred to as showingdetails-of construction.-

As shown in Figs. 1 and 7 of the drawings, the doup heddle, indicated enerally by the reference character I0, includes a doup needle ll of generally inverted U-shape, having a rounded upper end I I at which is located an eye I2 for the doup thread. Each of the depending legs L of doup needle I I is preferably provided, as is well known, with a slot l3 for the reception of aharness rod M (Fig. 8 so actuated as yieldingly to urge the doup needle downwardly.

The illustrated doup heddle H3 further includes two lifting heddles I! and I8. Lifting heddle I1 is; providedat its top and bottom with slots for the reception of the horizontal rods of one harness 22, and lifting h-iddle I8 is provided at its top and bottom with slots for the reception of the horizontal rod of another harness 20, the two harnesses and their lifting heddles l1 and I8 being moved up and down by a dobby motion (not shown) as customary in leno Weaving.

Each lifting heddle l1 and I8 comprises a twe ply portion, between the two plies of which one of the respective legs L of the doup needle ll extends, so that the doup needle is lifted by whichever lifting heddle I! or I8 is raised by its harness at the moment.

. Each doup thread d extends through the eye |=2 of one of the doup needles, as indicated above, and also between the two lifting heddles I! and I8. The standard thread s is threaded between the two lifting heddles I! and I8 in the same direction as the doup thread but does not pass through the eye of the doup needle. Fig. 2 shows the parts in the positions which they occupy when the shed is closzd for leno weaving. As illustrated, the standard thread s and the doup thread ddo not cross when the shed is closed: The construction of the doup heddle I0 is suchv that when the threads are passed through it, as shown in the drawings, the raising of the lifting heddle l1 carries the doup thread :1 above the standard thread s on the far side of the latter, as. viewed in Figs. 1 and 4, thus douping to the left. Similarly raising the lifting heddle I8 car rie's' the doup thread 11 above the standard thread son the near side of the latter, as shown in Fig. 3, thus douping to the right. After the formation of each successive open shed in leno weavi ing, whether douping to the right or left, the shuttle 2 passes through the shed, laying a pick P (Fig. 9) of filling between the lifted doup thread d forming the top wall of the shed, and the depressed standard threads 3 forming the bottom wall of the shed.

The. standard harmssesH. are shown as eight in-v number (Fig.1 although a. greater or lesser number may be used. Each standard heddle 23 is provided at its top and bottom with a slot for the reception of the horizontal rod 3| of the corresponding standard harness. Somewhat above the mid-point of each standard heddle 23 an eye 35 is provided for the passage of one of the standard threads 8. The standard harnesses are actuated by any suitable mechanism, for instance the well-known pump-rod and quadrant, so as to move the harnesses between the positions shown in Fig. 2 and Fig. 3 during leno weaving, that is to say, to impart to the standard harnesses a half-shedding motion so as to carry the standard threads 8 from the closedshed position to the depressed, open-shed position and vice versa. Thus in leno weaving the closing of the shed and the opening of the shed arebrought about by cooperative actuation of the doup needles and such of the standard harnesses as take part in the leno weaving, each of these elements moving from the closed-shed position, such as shown in Fig. 2, alternately to the open-shed positions of Figs. 1 or 3.

The doup threads (1, which have been separated from the standard threads of the warpby any suitable guides, pass forwardly toward the doup needLs beneath the dead rod, said rod being sometimes ,referred to as a vibrating bar or dancing rod. This dead rod R is, as known in the art, yielding mounted so that it may vibrate vertically in response to varying tensions of the doup threads. Usually, though not necessarily, the dead rod R, in its vibratory motion, makes contact with the standard threads s as well as the doup threads (1 which pass beneath it In accordance with prior practice (Fig. 6), if a doup thread d were to extend from the dead rod R to the doup needle eye on the near side of the standard heddles 23 (douping to the right with slack shed formation), the apex of the rear shed angle A would be located to the rear of thestandard heddle 23 carrying the corresponding standard thread s (at least as respects the forwardly located harness). The angle G between the runs R and R of doup thread at the front and rear of the doup needle is thus very obtuse. On the other hand, the apex of the rear shed angle A will be disposed forwardly of the standard heddle 23 which carries the corresponding standard thread when the doup thread is crossed to the far side of the standard thread (Fig. 5) in douping to the left, thus making the angle G more acute and producing a tight shed. When the doup thread is thus crossed to the far side of the standard thread (Fig. 5), the apex of the rear shed angle A is necessarily located forwardly of the standard harness heddle 23 and the doup thread is thus held downwardly and d-flected from its normal course as shown in Fig. 5 by the tensioned standard thread s while the latter is deflected upwardly (from its normal course between the heddle eye and the fell of the cloth) by the tension of the doup thread, the threads partially wrapping about each other just forwardly of the heddle eye. Since the threads are thus partially wrapped before the shed is completely opened, the result is that one thread saws against the other, causing chafing. While the variable location of the apex of the rear shed angle A of a single standard thread s of the front standard harness H and its corresponding doup thread dhas just been described, similar efiects will occur with respect to the doup andstandard: thread threads of several of the forwardly located standard harnesses. It may be ascertained (by projecting a straight line from the doup needle eye (Fig. 1) tangent to the dead rod R) that, as illustrated, (at least in the case of the forward harnesses) slack sheds and tight sheds will be formed at alternate doupings if the doup threads in customary manner pass the standard heddles while disposed always at the same side of the latter, as illustrated in Figs. 5 and 6.

In accordance with the present invention, the several forward standard harnesses, whose heddles would otherwise form tight and slack sheds, as above described, are provided with elongate slots 4'! which cooperate with the douping mech ani'sm to insure uniformity of conditions as 'r espects thread-tensioning and shed shape and dimensions when douping to the right and left, re spectively. These slots 41 each extend from a point below, and preferably closely adjacent to the eye 35, downwardly substantially to the slot which receives the lower rod 3!. The upper end of each slot 41 is separated from the thread eye 35 by a portion of the material of the heddle which thus forms a separator to prevent rubbing contact of the standard and doup threads where they pass through the heddle. As illustrated in the drawings, each doup thread is threaded through the slot 4? in the same direction that the corresponding standard thread 3 is threaded through the thread eye 35 of the heddle. The slots 4? are suificiently long so that when the standard harnesses are used for plain weaving (while leno weaving is suspended and the doup threads are in the depressed idle position) the upward motion of the standard heddles when raised to the extreme upper limit of their shedding mo tion will not substantially displace the idle runs of doup thread. When the doup thread and corresponding standard thread are thus threaded through the standard heddle, each of these threads extends through the heddle from one side to the other of the latter, and where they thus pass through the heddle they are maintainedin substantially the same vertical plane, that is'to say, one is substantially directly above the other.

Comparing, for example, the positions of the threads of the visible heddle 23 of the front standard harness H in Figs. 3 and 4, it will be observed that the slot 4! positions the doup thread 173 so that the apex of the rear-shed angle A is always located forwardly of the heddle whether douping to the right or left. Moreover, the positioning of the doup thread at the top of its slot 4?, which is vertically separated from the standard thread eye 35, insures that the rear shed angle A (Whether douping to the right or left) will be prevented from closing rearwardly upon the heddle 23, and will always occur sufficiently forwardly of the heddle eye to prevent the doup thread from being jammed or chafed between the standard thread and heddle. Neither the doup ing thread nor standard thread is deflected vertically by the other at any point between the standardharness and doup needle. There isno tendency for the doup thread to lift the standard thread whether douping to the right or. toflthe left. As viewed in the drawings (Figs. 3 and 4), the runs R of doup thread which lead from the rear shed angle A follow substantially thesame course when douping to the right or left, and

thus the tension of the doup thread is substan-,

tially the same in douping to the right or left. Since there is no vertical tensioning of the standard thread by the doup thread, thepaths a9 and tensions of the standard threads are like.- wise the same when douping to. the right or left. Thus, the creation of uneven tension and alternate tight and slack sheds is substantially avoided.

Thus, a lower general tension can be employed,

and warp breakage is reduced by such lower tension and by the avoidance of excessive tensions during douping. Warp breakage is reduced by the avoidance of the small-sized shed such as previously has occurred on alternate picks. An adeduate-sized shed, which does not squeeze the shuttle, is insured in both douping to the left and douping to the right, and the power consumption of the loom accordingly reduced. Any slackening orv compensating device employed to re- .lieve tension on the doup threads can operate in the same manner and to the same extent during .douping to. the right and douping to the left, and in adjusting the loom the tension on the threads can be initially adjusted ateither open shed position of Fig. l or of Fig. 3., and will then be the same for the other opposite open shed position. So-called tracking or pairing of the picks is avoided by the fact that the same tensions are employed in both open shed positions. Where the doup and standard threads are threaded through the slotand eye of a heddle as described above, it is .more convenient to thread them through the heddle from the same side, as illustrated in the drawings, but this is not essential and the doup and standard threads could be threaded through the standard heddle from opposite sides if desired and otherwise have the ,same' courses shown in the drawings.

The loom illustrated in the diagrams is adapted for weaving so-called figured goods by a proper shedding of the standard threads during suspension of leno weaving. In Fig. 8 the doup heddles .10. are shown as lowered'so as to depress the doup threads and cause them to lie inactive at the bottom of the douping shed, the mechanism for lifting the heddles I? and I8 being temporarily inactive. The standard harnesses, or selected ones of them, are then given a full shedding mo.- :tion by the dobby or other appropriate mecha .nism (not shown). Fig. 8 shows by way of example the front harness of the group of harnesses H raised and the next harness to the rear lowcred, the slots 47 through which the doup threads pass being so long that the idle doup threads are not deflected by the raising of the harnesses H to the full upward shedding position. It will be understood that after weaving one or more plain picks with the parts disposed as in Fig. 8, the operation of the doup heddles may be resumed so that the loom reverts to the weaving of leno fabric as in Figs. 1, 2,.and .3.

I am aware that there has been disclosed in United States Patents Nos. 413,440. and 825,244, primarily for use in weaving tapestry and velvet carpet, a heddle having an eye for one warp yarn and an elongate slot for a stuifer yarn. Such construction of the heddle affords a certain degree of lost motion between the heddle and the includes, means for suspending leno weavingwhile weaving plain fabric, said loom having doup nee:- dlesfor crossingdoup warps with standard warps, and heddles for the standard warps, e h stand: ard heddle having an eye for the passage of ,a standard warp, each standard heddle also having an elongate. slot for the passage of the correspond? ing doup warp, saidslot being long enough to al: low full shedding of the standard warp, during plain weaving, without Substantial displacement of the doup thread from an inactive idle position.

2. In combination in aloom comprising doup,- iing mechanism, including .doup'needles, operative to. form sheds .of doup and standard threads, the loom including a standard harness of fiat metal heddles provided with eyes for the standard threads, each heddle of said harness having. in addition to said eye and separate therefrom, an elongate slot for the reception of the doup thread corresponding to the: standard thread which passes through the eye of said heddle and guide means located rearwardly of the standard harness for guiding the doupv threads, the doup needles, heddle slots and guide means being so located 1'61? atively .to .each other that at each open lenoshed the doup thread is positioned by engagement with the end of the slot nearest to said eye.

3. In combination'ina loom comprisingstandeard harnesses including flat metal heddles pro:- vided with. eyes for standard. threads, the heddles being operative to move the standard threads be tween'closed shed andopen shed positions, a doup harness including doup needles adapted to move doup threads fromeither side to the opposite side of the corresponding standard threads while in the closed shed position and then to the open shed position, each heddle of at least the forward standard harness having elongate slots for doup t reads. separate from the eyes for the standard threads, thereby to prevent vertical deflection of either of corresponding doup and standard threads by the other, in the vicinity of the standard harness, while douping either to the right or left.

4. In comb nation-in a loom equipped for figure weaving and designed to form sheds of doupand standard threads for leno weaving, and to form sheds of standard threads during suspension of leno weaving, the loom includ ng standard hare nesses each having heddles provided with eyes for the standard threads, each standard heddle ofat least the forward harness having, in addition to said eye, and separate therefrom, an elongate slot forthe reception of the doup thread corresponding to the standard thread which passes through the eye of said heddle, and a gu de rod to the rear of the standard harness for guiding the doup threads on their way to said heddle slots, an inactive run of each doup-thread extending from-the guide-rod-to the lay oftheloom during suspension of leno weaving, the slots in the heddles being so long that said inactive runs of doup threads are not substantially deflected by the motion of the standard heddles when operated for full shedding during suspension of lenoweaving. I

5. In combination in a weaving loom of thelsind designed for alternative plain and leno weaving and which comprises doup heddles, adeadrodfor guiding doup threads on their way to the doup heddles, a pluralityof standard thread harnesses which are given a half-shedding motion during leno weaving and a full-shedding motion during plain weaving, and wherein the operation of the doup heddles is suspended during plain weaving, characterized in that each of the heddlesof .athe

foremost, at least, of the standard harnesses has an eye for the standard thread and an elongate slot below the eye for the passage of the corresponding doup thread, the slot being so long that when the standard heddle is moved to form a full 'she'd during plain weaving the course of the idle doup thread is substantially unchanged by movement of the standard heddles.

6. In combination in a weaving loom of the kind designed for alternative plain and leno weaving and which comprises doup needles, a plurality of standard thread harnesses to which a shedding motion is imparted, each heddle of the standard harness being aflat metal strip having an aper- I ture slightly above its mid-point for the passage of a standard thread, characterized in that each standard heddle has an elongate slot below said eye for the passage of the corresponding doup thread, said slot being so long that movementof the heddle to the extreme limits of its shedding 1 motion does not deflect the doup thread.

7. In combination in a weaving loom of the kind designed for alternative plain and leno weaving and which comprises doup needles, a plurality of standard thread harnesses to which a shedding motion is imparted, each' heddle of the standard harness being a flat metal strip having an aperture for the passage of a standard thread, characterized in that each standard heddle also has an aperture for the corresponding doup thread of a pair, said latter apertures being so shaped and located that movement of the heddles to the ex- :treme limits of shed formation do not deflect the :doup threads from their normal path.

8'. In combination in a weaving loom designed 'to weave leno fabric and which has doup heddles and means for actuating them and standard heddles and means for actuating them, the standard heddles being to the rear of the doup heddles, characterized in that each standard heddle is a metal strip having an eye for the passage of the standard thread and an'aperture 'for the'passage of the corresponding doup thread whereby the standard and doup threads of a pair are disposed in substantially the same vertical plane where they pass a standard heddle. 9. In combination in a weaving loom designed to weave leno fabric and which has doup heddles and means for actuating them and standard heddles and means for actuating them, the standard heddles being to the rear of the doup heddles, characterized in that each standard heddle is a fiat metal strip having an eye located at a point substantially mid-way its length and a'slot extending from a point just below the eye substantially to the lower end of the heddle. "10. In combination in aweaving loom designed towe'ave leno fabric and which has doup lied dles and means for actuating them and stand-'- ard heddles and means for actuating them,the standard heddles being to the rear of the doup heddles, characterized in that each standard lheddle is of metal and has an eye for the passage of the standard thread and an elongate slotfor the passage of the corresponding doup t w, a I a I a.

11. In combination in a loom designed to form sheds ofdoup and standard threads, each vshed Qliaving a-front and a rear angle, the loom includ-. ing-standard harnesses each having heddles pro-,- vided with eyes for the standard threads, each heddle of the front standard harness having, in addition to said eye and separate therefrom, an elongate slot for the reception ofthe doup thread Number corresponding to the standard thread which passes through the eye of said heddle, the eye and slot of said heddle being constructed and arranged to locate the rear shed angle adjacent to but forwardly of said standard heddle in both the right and left douping position.

12. In combination in a weaving loom designed to form sheds of doup and standard threads, each shed having front and rear angles, the loom including standard harnesses each having heddles provided with eyes for the standard threads, a full shedding motion being imparted to said standard harnesses during plain weaving, characterized in that each heddle, of some at least of said standard harnesses, has an elongate slot for a doup thread, said slot being separate from the eye thereby to insure the location of the rear shed angle at the same point in both right and left douping positions of the threads.

13. In combination in a loom designed to form sheds of doup and standard threads, each shed having a front and a rear angle, the loom including standard harnesses each having heddles provided with eyes for the standard threads, guide means in the rear of the standard harnesses for guiding the doup threads, the heddles of the front standard harness, at least, being slotted to receive the doup threads, thereby preventing the threads which form the rear shed angle from closing upon said slotted heddles.

14. Method of controlling the warp in a leno loom equipped for figure weaving and having doup needles for crossing doup warps with stand ard warps and having standard heddles for shedding warps during suspension of leno weaving, characterized in guiding the standard and doup warps of a pair to lie always in the same vertical plane at the location of the standard heddle, suspending the shedding motion of the doup needles during plainweaving, and allowing each standard heddle to move freely relatively to the corresponding doup warp while leaving the latter in a fixed idle position.

15. Method of controlling the warp in a leno loom equipped for figure weaving and having doup heddles for crossing doup warps with standard warps and having standard heddles for shedding warps during suspension of leno weaving, characterized in guiding the standard and doup warps of a pair to he always in the same vertical plane at the location of each standard heddle and, during plain weaving, imparting a full shedding motion to each standard warp while maintaining each doup warp in a fixed idle position.

HUGH J. CARRAGHER.

REFERENCES CITED "The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date 413,440 Firth Oct.,22, 1889 632,834 Cooker I Sept. 12, 1899 840,275 Whitmore Jan. 1, 1907 899,973 Hannah Sept. 29, 1908 1,757,947 Snow May 6, 1930 2,389,258 Hilton Nov. 20, 1945 FOREIGN PATENTS Number Country Date Great Britain Feb. 19, 1856

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