Online Encyclopedia

Search over 40,000 articles from the original, classic Encyclopedia Britannica, 11th Edition.

INDUSTRIAL

Online Encyclopedia
Originally appearing in Volume V28, Page 448 of the 1911 Encyclopedia Britannica.
Spread the word: del.icio.us del.icio.us it!

INDUSTRIAL  TECHNICOLOGY All See also:

weaving schemes are reducible to a few elementary principles, but no attempted See also:classification has been quite successful, for fabrics are constantly met with that possess characteristics supposed to be See also:peculiar to one class, but lack others which are deemed equally typical . Nevertheless, since some classification is essential, the following will be adopted, namely: See also:Group i, to include all fabrics made from one warp and one weft, provided both sets of threads remain parallel in the finished See also:article and are intersected to give the requisite feel and See also:appearance: Group 2, to include (a) fabrics constructed from two warps and one weft, or two wefts and one warp, as in those that are backed, reversible and figured with extra material; (b) two or more distinct fabrics built simultaneously from two or more warps and wefts, as in two, three and other ply cloths; (c) fabrics built by so intersecting two or more warps and wefts that only one texture results, as in See also:loom-made tapestries and figured repps . Group 3, to include fabrics in which a portion of the weft or warp rises vertically from the ground-See also:work of a finished piece, as in velveteens, velvets, plushes and piled carpets . See also:Groups 4, to embrace all fabrics in which one portion of the warp is See also:twisted partially, or wholly, See also:round another portion, as in gauzes and lappet cloths . Although some fabrics do not appear to fall into any of the above divisions, and in others the essential features of two or more groups are combined, yet the grouping enumerated above is sufficiently inclusive for most purposes . The fabrics included in Group i are affected by the nature and closeness of the yarns employed in their construction, by See also:colour, or by the See also:scheme of intersecting the threads . The most important See also:section of this group is See also:Plain See also:Cloth, in which the warp and weft threads are approximately equal in thickness and closeness, and pass over and under each other alternately, as in fig, i, which shows a See also:design, See also:plan and two sections of plain cloth . Such a fabric would, therefore, appear to admit of but slight ornamentation, }et this is by no means the See also:Case, for if thick and thin threads of warp and weft alternate, the resultant fabric may be made to assume a corrugated appearance on the See also:face, while beneath it remains See also:flat, as in poplins, repps and cords . A plan and a See also:longitudinal section of a repp cloth is shown at fig . 2 . Colour may also be employed to See also:ornament plain fabrics, and its simplest application produces stripes and checks . But colour may convert these fabrics into the most See also:artistic and costly productions of the loom, as is the case with tapestries, which Fin. i.—Plain Cloth .

are at once the See also:

oldest and most widely diffused of ornamented textiles . Tapestries only differ from See also:simple plain cloth in having each See also:horizontal See also:line of weft made up of numerous See also:short lengths of parti-coloured See also:thread . Many See also:fine specimens of this See also:art have been recovered from See also:ancient See also:Egyptian and Peruvian tombs, and many are still produced in the Gobelins and other celebrated manufactories of See also:Europe . Twills are next in importance to plain cloth on, See also:account of their wide range of application and See also:great variety of effects; in elaborately figured goods their use is as extensive as where they provide the only ornament . Twills invariably See also:form See also:diagonal ribs in fabrics, and these are due to the intervals at which the warp and weft are intersected; thus two or more warp threads are passed over or under one or more than one weft thread in See also:regular See also:succession . Twills are said to be equal when similar quantities of warp and weft are upon the face of a fabric, unequal when one set of threads greatly preponderates over the other set, as in See also:figs . 3, 4, which require four warp and weft threads to See also:complete the scheme of intersections . If the ribs form angles of 45 degrees, the warp and weft threads per See also:inch are about equal in number, but for an unequal See also:twill the material most in See also:evidence should be closest and finest . The See also:angle formed may be greater or less than 45 degrees, as in figs . 5, 6; if greater, the warp preponderates, if less, the weft preponderates . Twills are simple and See also:fancy; both terms refer to the schemes of intersecting . In the Fin .

2.-Repp Cloth . former the same number of warp threads are placed successively above or below each weft thread, and the ribs are of See also:

uniform width, as in figs . 3, 4 . In the latter more warp threads may be above one pick than another, the ribs may vary in width and small ornament may be introduced between the ribs, as in figs . 5, 6 and 7, where the dark squares represent warp upon the See also:surface . Twills may be broken up into zigzags, lozenges, squares and other geometrical designs; all of which may be produced by reversings in the diagonal lines, or by See also:reversing the weave of an unequal twill . Fig . 8 is a zigzag, namely, a twill reversed in one direction . Fig . 9 is a See also:diamond, or a twill reversed in two directions, and fig. io is a See also:diaper, or an unequal twill which gives a warp face in one See also:place and a weft face in another . Satins and satteens form another important section of Group 1 . In a satin the bulk of the warp, and in a satteen the bulk of the weft, is on the face of a fabric .

If perfect in construction both See also:

present a smooth, patternless appearance, which is due in See also:part to the scheme of intersections, in part to using fine material for the surface threads and placing it See also:close enough together to render the points of intersection invisible; the threads of the other set being coarser and fewer in number . Satins differ from twills in having each warp thread lifted, or depressed, separately, but not successively . From five to upwards of See also:thirty threads of warp and weft are required to complete the various schemes of intersecting . If the intervals between the intersections are equal the weave is said to be perfect, as in fig . 11, but if the intervals are irregular it is said to be imperfect, as in fig . 12 . In Damasks a satin is combined with a satteen weave, and since any desired See also:size and shape of either weave may be produced, great facilities are offered for the development of all kinds of ornamentation . But in See also:combination neither the satin nor the satteen can be perfect in construction, for one requires a preponderance of warp, the other a preponderance of weft; as a sequence every point of intersection is distinctly visible on both surfaces . Brocades are fabrics in which both sets of threads may be floated irregularly upon the surface to produce ornamental effects, and they may be taken as typical of all one warp and one weft fabrics that are figured by irregularly floated materiaie', wnether the threads are uniformly or irregularly distributed, and whether one weave or several weaves be employed . Group 2 includes all backed and reversible fabrics, as well as those ornamented with extra material and compounded . Cloths intended for men's See also:wear are often backed, the See also:object of which is to give See also:weight and bulk to a thin texture without interfering with the Satteen . Satteen .

face effects . Either warp or weft may be used as backing; if the former there are two See also:

series of warp to one series of weft threads, while in the latter there are two series of weft to one series of warp threads . The face material is superposed upon that of the back, but the ratio of face threads may be one or two to one of back . In See also:order to avoid disturbing the face weave, only those threads are used to bind the backing that are hidden on the face, as in fig . 13, which gives the design and a transverse section of a backed fabric; A is face weft; B back weft, and the circles are warp threads; of the latter C, D, are beneath both B and A . This See also:diagram will serve equally as a longitudinal section of a warp-hacked fabric, if A represents a thread of face warp, B a thread of back warp and the circles are weft threads . Weft backing is capable of giving a more spongy feel to a fabric than warp, because softer materials may be used, but in these fabrics the length output of loom is reduced by See also:reason of the wefts being superposed . Warp-backed fabrics, whether uniformly coloured or striped, do not materially reduce the output of a loom, for every weft thread adds to the cloth length . Reversible fabrics may have either two series of differently coloured wefts or warps to one of the other series, in which event they may be similarly figured on both sides by causing the threads of the See also:double series to See also:change places, as in the design and transverse section, fig . 14; or, by allowing one series to remain constantly above the other, as in backed cloths, both sides may be similar or dissimilar in colour and See also:pattern . Fabrics figured with extra material may have two series of warp or weft threads to one series of the other set, and they may yield reversible or one-sided cloths . A ground texture may have extra material placed above or below it, as in fig .

15, where a design and transverse section of the cloth are given; the waved lines and circles represent a See also:

cross-section of plain cloth and A is a thread of extra material; or See also:ordinary and extra material may be used See also:con-jointly for figuring . See also:Compound cloths must have at least two textures, and be as distinct in See also:character as if See also:woven in See also:separate looms; they have many advantages over backed cloths, thus: the same design and colouring may be produced on both sides; where bulk and weight are required a fine surface texture may be formed over a ground of inferior material, and soft weft be passed between the upper and See also:lower textures . The fabric is more perfect and admits of either simple or elaborate patterns being wrought upon the surface, with simple ones beneath, as in piques and matelasses . One texture may be constantly above the other and connected at the selvages only, as in See also:hose pipes and See also:pillow slips; or at intervals a thread may pass from one texture into the other, in which event both are See also:united, as in many styles of See also:bed-covers and vestings . If differently colouree' ... . . ^ .. :':..Y+.^ r.: a^NU . viii"iiN' . ^ ii.Nii .A ^ Fabric . Extra Weft . the textures may change places at See also:pleasure, as in See also:Kidderminster carpets; or, from three to twelve textures may be woven simultaneously, and united, as in belting cloth .

There may be from one to three threads of face warp to one of back, and the wefting may or may not correspond with the warping . Fig . 16 shows the face and ^^.^^ M ME ' 14' o B C D Fabric . A A A back weaves, the design, and a transverse section of a compound cloth with two threads of face warp and weft to one of back, and both are stitched together . The circles in the upper and lower lines represent face and back warps respectively, and A, B, C are weft threads placed in the upper and lower textures . Loom-made tapestries and figured repps form another section of Group 2 . As compared with true tapestries, the loom-made articles have more limited colour schemes, and their figured effects may be obtained from warp as well as weft, whether interlaced to form a plain face, or See also:

left floating more or less loosely . Every weft thread, in passing from selvage to selvage, is taken to the surface where required, the other portions being See also:bound at the back . Some specimens are reversible, others are one- sided, but, however numerous the warps and wefts, only one texture is produced . When an extra warp of fine material is used to bind the wefts firmly together a plain or twill weave shows on both sides . If a single warp is employed, two or more wefts form the figure, and the warp seldom floats upon the surface . Where warps do assist to form figure it rarely happens that more than three can be used without overcrowding the See also:reed .

Fig . 17 gives the design, and a transverse section of a reversible See also:

tapestry in four See also:colours, two of which are warps and two N.,mep ,N.2se p wefts . If either warp or weft is on the ° ° surface, corresponding threads are be- See also:neath . The See also:bent lines represent weft and FIG . 17.—Tapestry with the circles warp . Figured repps differ Two Warps and Two from plain ones in having threads of one, Wefts. or more than one, thick warp floated over thick and thin weft alike; or, in having several differently coloured warps from which a fixed number of threads See also:ace lifted over each thick weft thread; the face of the texture is then uniform, and the figure is due to colour . Group 3 . Piled Fabrics.—In all methods of weaving hitherto dealt with the warp and weft threads have been laid in longitudinal and transverse parallel lines . In piled fabrics, however, portions of the weft or warp assume a See also:vertical position . If the former there are two series of weft threads, one being intersected with the warp to form a See also:firm ground texture, the other being bound into the ground at regular intervals, as in the design and transverse section of a See also:velveteen, fig . 18; the circles and waved lines form plain cloth, and the loose thread A is a See also:pile pick . After leaving the loom all threads A are cut by push- See also:ing a See also:knife lengthwise between the plain cloth and the pile .

As each pick is severed both pieces rise vertically and the See also:

fibres open out as at B . Since the pile threads are from two to six times as numerous as those of the ground, and rise from an immense number of places, a uniform See also:brush-like surface is formed . Raised figures are produced by carrying the threads A beneath the ground cloth, where no figure is required, so that the knife shall only cut those portions of the pile weft that remain on the surface . The effect upon the face varies with the See also:distribution of the binding points, and the length of pile is determined by the distance separating one point from another . See also:Chenille.—When chenille is used in the construction of figured weft-pile fabrics, it is necessary to employ two weaving operations, namely, one to furnish the chenille, the other to place it in the final fabric . Chenille is made from groups of warp threads that are separated from each other by considerable intervals; then, multi-coloured wefts are passed from See also:side to side in accordance with a predetermined scheme . This fabric is next cut midway between the groups of warp into longitudinal strips, and, if reversible fabrics such as table-covers and curtains are required, each See also:strip is twisted axially until the protruding ends of weft radiate from the core of warp, and form a See also:cylinder of pile . In the second weaving this chenille is folded backward and forward in a second warp to See also:lay the colours in their appointed places and pile projects on both sides of the fabric . If chenille is intended for carpets, the ends of pile weft are bent in one direction, and then woven Into the upper surface of a strong ground texture . Warp-piled Fabrics have at least two series of warp threads to one of weft, and are more varied in structure than weft-piled fabrics, because they may be either plain or figured, and have their surfaces cut, looped or both . Velvets and Plushes are woven single and double . In the former case both ground and pile warps are intersected with the weft, but at intervals of two or three picks the pile threads are lifted over a See also:wire, which is subsequently withdrawn; if the wire is furnished with a knife at its See also:outer extremity, in withdrawing it the pile threads are cut, but if the wire is pointed a line of loops remains, as in See also:terry See also:velvet .

Fig . 19 is the design, and two longitudinal sections of a See also:

Utrecht velvet . The circles at A are weft threads, and the bent line is a pile thread, part of which is shown cut, another part beinglooped over a wire . At B the circles are repeated to show how the ground warp intersects the weft . Double Plushes consist of two distinct ground textures which are kept far enough apart to ensure the requisite length of pile . As weaving proceeds the pile threads are interlaced with each series of weft threads, and passed from one to the other . The uniting pile material is next severed midway between the upper and lower textures, and two equal fabrics result . Fig . 20 gives three longi- A c B o FIG . 19.—Utrecht Velvet . FIG . 2o.—Double See also:Plush .

tudinal sections of a double pile fabric . The circles A, B are weft threads in the upper and lower fabrics respectively; the lines that interlace with these wefts are pile warp threads which pass vertically from one fabric to the other . At C, D the circles are repeated to show how the ground warps intersect the wefts, and at E the arrows indicate the cutting point . Figured Warp-pile Fabrics are made with regular and irregular cut and looped surfaces . If regular, the effect is due to colour, and this again may be accomplished in various ways, such as (a) by knotting tufts of coloured threads upon a warp, as in Eastern carpets ; (b) by See also:

printing a fabric after it leaves the loom; (c) by printing each pile thread before placing it in a loom, so that a pattern shall be formed simultaneously with a pile surface, as in tapestry carpets; (d) by providing several sets of pile threads, no two of which are similar in colour; then, if five sets are available, one-fifth of all the pile warp must be lifted over each wire, but any one of five colours may be selected at any place, as in See also:Brussels and See also:Wilton carpets . Fig . 21 is the design, and a longitudinal section of a Brussels See also:carpet . The circles . represent two tiers of weft, and the lines of pile threads, when not lifted over a wire to form loops, are laid between the wefts; the ground warp interlaces with the weft to bind the whole together . When the surface of a piled fabric is irregular, also when cut and looped pile are used in combination, design is no longer dependent upon colour, for in the former case pile threads are only lifted over wires where required, at other places a flat texture is formed . In the latter case the entire surface of a fabric is covered with pile, but if the figure is cut and the ground looped the pattern will be distinct . Group 4 .

Crossed Weaving.—This group includes all fabrics in which the warp threads intertwist amongst themselves to give intermediate effects between ordinary weaving and See also:

lace, as in gauzes . Also those in which some warp threads are laid transversely in a piece to imitate See also:embroidery, as in lappets . Plain See also:Gauze embodies the principles that underlie the construction of all crossed woven textiles . In these fabrics the twisting of two warp threads together leaves large interstices between both warp and weft . But although See also:light and open in texture, gauze fabrics are the firmest that can be made from a given quantity and quality of material . One warp thread from each pair is made to cross the other at every pick, to the right and to the left alternately, therefore the same threads are above every pick, FIG . 22.—Plain Gauze. but since in See also:crossing from side to side they pass below the remaining threads, all are bound securely together, as in fig . 22, where A is a longitudinal section and B a plan of gauze . See also:Leno is a See also:muslin composed of an See also:odd number of picks of a plain weave followed by one pick of gauze . In texture it is heavier than gauze, and the cracks are farther apart transversely . Fancy Gauze may be made in many ways, such as (a) by using crossing threads that differ in colour or See also:count from the remainin threads, provided they are subjected to slight tensile See also:strain; (b) by causing some to twist to the right, others to the left simultaneously; (c) by combining gauze with another weave, as plain, twill, satin, See also:brocade or pile; (d) by varying the number of threads that cross, and by causing those threads to entwine several ordinary threads; (e) by passing two or more weft threads into each crossing, and operating any assortment of crossing threads at pleasure . Fabric .

a ovc•~.•.r• 0 oa:. i~oo< . a:•~e: •eo Ko ...rune•.... a ne c Geo... fl.neeeeeore.u•,• ^ uoer . ~ue~s..r _ teee Lappet weaving consists in diapering the surface of a plain or gauze fabric with simple figures . This is done by See also:

drawing certain warp threads into a transverse position and then lifting them over a thread of weft to See also:fix them in the texture; after which they are moved in the opposite direc- tion and lifted over the following pick . The material between one binding point and another must See also:float loosely, and this limits the usefulness of lappet figuring . In fig . 23, the thick lines show a lappet spot upon a plain texture . Notwithstanding diverse struc- See also:ture, intricate mechanisms are not essential to the See also:production of either simple or complex textures; the most elaborate and beautiful specimens of the See also:weaver's art have been manufactured upon simple machinery . Weaving Machinery . The longitudinal threads of a fabric are called warp, See also:caine, twist and organzine, and the transverse threads are weft, shoot, woof, filling and tram . A loom for intersecting these several threads must provide for: (I) Shedding; namely, raising and lowering the warp threads in a predetermined sequence so as to form two lines between which the weft may be passed . (2) Picking, or ,placing lines of weft between the divided warp .

(3) Beating-up, or striking each weft thread into its appointed position in the fabric . (4) Letting-off, or holding the warp tense and delivering it as weaving proceeds . (5) Taking-up, or drawing away the cloth as manufactured . (6) Temples, for stretching the fabric widthwise in order to prevent the edge threads of a warp from injuring the reed, and from breaking . See also:

Power looms require the above-named contrivances to See also:act automatically, and in addition: (7) A weft-See also:fork, to stop a loom when the weft becomes exhausted or breaks . (8) Mechanism for stopping a loom when the See also:shuttle fails to reach its appointed See also:box . (9) For weaving cross stripes, multiple shuttle boxes are needed to bring different colours, or See also:counts of weft, into use at the proper See also:time . (so) In some looms a See also:device for automatically ejecting a spent cop, pirn or shuttle, and inserting a full one, is requisite . (II) If a weaver has to attend to a greater number of looms than usual, a device for stopping a loom when a warp thread fails is essential . The See also:Hand-Loom.—During the 17th and the first See also:half of the r8th centuries it was observed that wherever any See also:branch of the textile See also:industry had been carried to a high See also:state of excellence the looms used to manufacture a given fabric were similar in essentials, although in structural details they differed greatly . See also:Prior to the invention of the See also:fly shuttle by See also:John See also:Kay, in 1733, no far-reaching invention had for generations been applied to the hand-loom, and subsequently the See also:Jacquard See also:machine and multiple shuttle boxes represent the thief changes . A hand-loom as used in Europe at the present time (see fig .

24) has the warp coiled evenly upon a See also:

beam whose gudgeons are laid in open steps formed in the loom framing . Two See also:ropes are coiled round this beam, and weighted to prevent the warp from being given off too freely . From the beam the threads pass alternately over and under two See also:lease rods, then separately through the eyes of the shedding See also:harness, in pairs between the dents of a reed, and finally they are attached to a cloth See also:roller . For small patterns healds are used to form sheds, but for large ones a Jacquard machine is required . Healds may be made of twine, of wire or of twine loops into which See also:metal eyes, called mails, are threaded . But they usually consist of a number of strings which are secured above and below upon wooden laths called shafts, and each See also:string is knotted near the See also:middle to form a small See also:eye . From two to twenty-four pairs of shafts may be employed, but the healds they carry most collectively equal the number of threads in the warp . These healds will be equally or unequally distributed upon the shafts according to the nature of the pattern to be woven, and the threads will be See also:drawn through the eyes in a predetermined order . The upper shafts are suspended from pulleys or levers, and the lower ones are attached directly or indirectly to treadles placed near the See also:floor . The weaver depresses these treadles with his feet in a 'sequence suited to the pattern, and the scheme of drawing the warp through the healds . When a treadle is pressed down, at least one pair of shafts will be lifted above the others, and the warp threads will ascend or descend with the healds to form a See also:shed for a shuttle, containing weft, to be passed through (see SHUTTLE) . The reed (fig .

25) is the See also:

instrument by which weft is beaten into position in the cloth; it also determines the closeness of the warp threads, and guides a moving shuttle from side to side . It is made by placing strips of flattened wire between two half round ribs of See also:wood, and binding the whole together by passing tarred twine between the wires and round the ribs . Such a reed is placed in the lower portion of a See also:batten, which is suspended from the upper framework of the loom . In front of the reed, and immediately below the warp, the projecting batten forms a See also:race for the shuttle to travel upon from side to side . Before Kay's invention a shuttle was thrown between the divided warp and 'caught at the opposite selvage, but Kay continued the projecting batten on both sides of the warp space, and constructed boxes at each end . Over each box he mounted a spindle, and upon it a See also:driver, or picker . Bands connected both pickers to a stick which the weaver held in his right hand, while with the left hand he controlled the batten . Thus: a treadle is pressed down by one See also:foot to form a shed; the batten is pushed back till a sufficient portion of the shed is brought in front of the reed, and the depressed threads See also:lie upon the shuttle race; a clear way is thus provided for the shuttle . A See also:quick See also:movement of the stick tightens the See also:cord attached to a picker and projects the shuttle from one box to the other . The batten is now drawn forward, and the reed beats up the weft left by the shuttle . As the next treadle is depressed to form another See also:division of the warp for the return movement of the shuttle, the last length of weft is en-wrapped between intersecting warp threads, and the remaining movements follow in regular succession (see fig . 26) .

In cases where the weft forms parti-coloured stripes across a fabric, also where different counts of weft are used, shuttles, equal in number c a, The warp beam. d, The reed in position for pick- b, The lease rods by which the e, ing, and also for beating-up . is divided and Woven cloth . warp crossed . c, c, Two pairs of shafts containing healds . f, The cloth beam . to the colours, counts or materials, must be provided . By See also:

Robert Kay's invention of multiple shuttle boxes, in 176o, much of the time lost through changing shuttles by hand was prevented . His drop boxes consist of trays formed in tiers and fitted into the ordinary shuttle boxes . Each See also:tray is capable of holding a shuttle, and by operating a See also:lever and plug with the forefinger and thumb of the left hand, the trays may be raised and lowered at pleasure to bring that shuttle containing the colour next needed into line with the picker . The Draw Loom.—Large figured effects were formerly produced in draw looms, where the warp threads were so controlled by separate strings that any assortment could be lifted when required . Thus: to the lower end of each string a dead weight, called a lingoe, was attached, and a few inches above the lingoe a See also:mail was fixed for the See also:control of a warp thread . The strings passed through a drilled See also:board which held the mails and warp threads facing the proper reed dents .

Still higher up, groups of strings were connected to See also:

neck cords; each group consisted of all strings required to rise and fall together constantly . If, for example, in the breadth of a fabric there were twelve repeats of a design, twelve strings would be tied to the same neck cord, but taken to their respective places in the comber board . The foregoing parts of a draw loom harness are clearly shown in fig . 27 : A are lingoes, and the dots represent mails . B is the comber board; between B and C are mounting strings and neck cords, two strings being attached to each cord; and C is the bottom board . Each neck cord, after being led through a perforated bottom board C, and over a grooved See also:pulley, was threaded through a See also:ring on the See also:top of a vertical cord called the simple, and passed horizontally to, and tied upon a See also:bar rigidly fixed near the See also:ceiling of the weaving See also:room . The simple cords were similarly attached to a bar placed near the floor . From one See also:hundred to several thousands of neck and simple cords could be used in one harness . The design to be reproduced in cloth was read into the parallel lines of the simple by looping a piece of string round each cord that governed warp threads to be lifted for a given shed; after which all the loops were bunched together . By pulling at a bunch of loops the simple cords were deflected and they caused all warp threads con-trolled by them to be lifted above the lever of those undisturbed . Similar bunches of loops were formed for every shed required for one repeat of a design, and they were pulled in succession by the draw-boy, while the weaver attended to the batten and picking . The Jacquard machine is the most important invention ever applied to the hand-loom, but it is not the work of one See also:man; it represents the efforts of several inventors whose labours extended over three-quarters of a See also:century .

This apparatus has taken the places of the simple, the loops, the pulleys and the draw-boy of the older shedding See also:

motion, but other parts of the harness remain unchanged . In 1725 Basile Bouchon substituted for the bunches of looped string an endless See also:band of perforated See also:paper by which the simples for any shed could be selected . In 1728 M . See also:Falcon constructed the machine since known as the Jacquard and operated it through the See also:medium of perforated See also:cards, but it was attached to the simple cords and required a draw-boy to manipulate it . In 1745 Jacques de Vaucanson united in one machine Bouchon's band of paper and the mechanism of Falcon . He placed this machine where the pulley box previously stood, and invented mechanism for operating it from one centre . It is said that about the See also:year 18ot J . M . Jacquard was called upon to correct the defects of a certain loom belonging to the state, in doing which he asserted that he could produce the desired effects by simpler means, and this he undoubtedly accomplished . In or about 1804 he discarded the simple and all but a few inches of the vertical neck cords; he placed Falcon's apparatus immediately over the centre of the loom and severally attached the upper portions of the neck cords to the hooks; all of which Vaucanson had previously done . He then perforated each face of a quadrangular See also:frame= used by Falcon to See also:guide the cards to the draw-boy, and since known as the cylinder—and invented means whereby the cylinder could be made to slide horizontally to and fro, and at each outward See also:journey make one-See also:quarter of a revolution . Cards were so held upon this cylinder by pegs that at each rotatory movement one was brought into See also:action and another moved away .

By means of two treadles placed beneath the warp one weaver could operate the entire loom . The cylinder was controlled with one foot, the selecting parts with in hanks or used in a saturated See also:

condition, require winding upon the other, and both hands were See also:free to attend to picking and beating- ~ pirns, or into cops of suitable sizes . Pirn winders differ greatly in up . • construction, but the See also:majority are furnished with conical shapers, In a Jacquard machine the warp threads are raised by rows of consisting either of slip cups, or of See also:cone rollers mounted upon studs. upright wires called hooks . See D, fig . 27 . These are bent at both extremities and are normally supported upon a bottom board C, which is perforated to permit the neck cords from the harness beneath to be attached to the hooks . Each of a series of horizontal needles E—one of which is shown enlarged and detached at the foot of the drawing—is provided with a See also:loop and a coiled eye; the former to permit of a to-and-fro movement, the latter to receive a See also:hook . The straight ends of the needles protrude about one-quarter of an inch through a perforated See also:needle board G, but the looped ends See also:rest upon bars placed in tiers . A wire passed through all the loops of the needles which form one vertical line limits the extent of their A lateral movement, and small helical springs, a, enclosed in a box F, impinge upon the loops of the needles with sufficient force to See also:press them and their hooks forward . A frame H, called a See also:griffe, is made to rise and fall vertically by a treadle which the weaver actuates with one foot . This frame contains a blade for each line of hooks, and when the See also:blades are in their lowest position the hooks are free and vertical with their heads immediately over the blades, hence, an upward movement given to the See also:grille would lift all the hooks and thereby all the warp threads .

Phoenix-squares

Only certain hooks, however, must be lifted with the griffe, and the selection is made by a quadrangular See also:

block of wood, I, called a cylinder, and cards which are placed upon it . Thus, each face of the cylinder has a perforation opposite each needle, so that if the cylinder be pressed close to the needle board the needle points will enter the holes in the cylinder and remain undisturbed . But if a card, which is not perforated in every possible place, is interposed between the cylinder and the needles, the unpunctured parts of the card close up some of the holes in the cylinder, and prevent corresponding needles from entering them . Each needle so arrested is thrust back by the advancing card; its See also:spiral See also:spring a is contracted arid its hook D is tilted as shown in the figure . If at this instant the griffe H ascends, its blades will engage the heads of all vertical hooks and lift them, but those dislocated by being tilted will remain unlifted So soon as the pressing force of a card is removed from the needles the See also:elasticity of the springs restores both needles and hooks to their normal positions . Cards are perforated by See also:special machinery from a painted design, after which they are laced into a See also:chain and passed over conical pegs upon the cylinder; the number required to weave any pattern equals the number of weft threads in that pattern . The cylinder is generally drawn out and turned by each upward movement of the grille, and restored to the needles by each downward movement, so that each face in succession is presented to the needles, and each rotatory movement brings forward a fresh card . As the griffe rises with vertical hooks a shed is formed, and a thread of weft is passed across the warp . The grille then descends and the operation is repeated but with a new combination of lifted threads for each card . A Jacquard may contain from too to 1200 hooks and needles, and two or more See also:machines may be mounted upon the same loom . Since Jacquard's time attempts have been made to dispense with hooks, needles, springs, cards, the cylinder and several other parts; machines have also been specially designed for effecting economies in the manufacture of certain fabrics; but although some of these devices are used in different sections of the industry, the single lift Jacquard remains unchanged, except in its details, which have been modified to give greater certainty of action to the moving parts . The most far-reaching changes are directly due to efforts made to adapt the Jacquard to fast See also:running power looms .

See also:

Alfred See also:Barlow, John and See also:William Crossley, and others, devised means whereby two hooks could control the same warp thread, and they provided the machine with two griffes, each capable of actuating alternate rows of hooks . One griffe was caused to ascend as the other descended, therefore, if one of the two hooks that operate a warp thread is lifted for the first shed, the other hook can begin to rise for a second shed immediately the first begins to fall . About half the time originally needed for shedding is thus saved, and as a result Jacquards can now be run at 210 to 220 picks per See also:minute . Preparing Warp and Weft for Weaving.—The power loom is only one of a series of machines which revolutionized weaving . Although See also:early inventors of the power loom did much to perfect its various movements, the commercial results were disappointing, chiefly because means had not been devised for preparing warp and weft in a suitable manner for such a machine . William See also:Radcliffe, of See also:Stockport, perceived these shortcomings, and concluded that, by division of labour, weaving could be brought into line with, the then recently invented, See also:spinning machinery . He, therefore, set himself the task of solving the problems involved, and by inventing the beam warper, the dressing sizing machine, the shuttle See also:tongue, and the See also:pin cop, he enabled the power loom to become a See also:factor in the textile industry . The See also:term preparation embraces winding, warping, sizing, See also:Yorkshire dressing, drawing-in, twisting and occasionally other operations . Weft Winding.—Weft yarns invariably receive simpler treatment than warp yarns ; in many cases none at all . Cops and ring spools pass See also:direct to the loom unless their dimensions are unsuited to the shuttles, in which case they, together with wefts bleached or dyed A pirn, whose See also:head is coned to See also:fit inside a shaper, is slipped over a spindle, and both are passed, either vertically or horizontally, through a shaper; the basal end of the spindle being flattened to enter a rectangular hole in a wharve which is driven from a central See also:tin See also:drum . A thread is attached to a rotating pirn, and a vibrating guider leads it to and fro inside the shaper . Both spindle and pirn recede from the shaper until the pirn is full, when they become stationary .

Hanks are carried by ryces, and cops and ring spools by skewers . Cop winders are chiefly used for coarse yarns, which they coil upon See also:

bare spindles . By this means a greater length of weft can be placed in a shuttle than when pirns are used . Warp winding consists in transferring See also:yarn from cops, ring spools or hanks, either to warpers, bobbins or cheeses (see See also:COTTON-SPINNING MACx1NE12Y) . Machines for this purpose are of two kinds, which are known respectively as spindle and drum . In the former each bobbin is placed upon a vertical spindle and rotated by frictional contact; a yarn guider meanwhile rises and falls far enough to lay the threads in even coils between the bobbin flanges . In the latter each bobbin, or See also:tube, is laid upon a rotating drum and a thread guide moves laterally to and fro; slowly for a bobbin, but quickly for a tube . Warping.--The number of longitudinal threads in a See also:web vary according to their closeness and its breadth . It is the See also:function of a warper to provide a sufficient number of parallel threads for a web, all of equal length, and to retain their See also:parallelism . Warpers are of three types, viz. See also:mill, beam and sectional . Mill warping is the oldest type now in extensive use . A mill warper has a creel in which from 50 to upwards of 300 bobbins or cheeses, are supported horizontally upon pegs, and the mill has a vertical See also:axis which carries three wheels, upon whose rims vertical staves are fixed about i ft. apart to form a See also:reel, from 5 to upwards of 20 yds. in circumference .

The threads from the creel are threaded in succession through leasing needles, then passed in groups of four to twenty threads between runners, and, finally, fastened by a peg to the mill staves . The needles are mounted alternately in two frames which may be moved up inclined planes; one to elevate odd threads, the other even ones, and both separations thus formed are retained upon separate pegs; this is the lease which enables a weaver to readily fix the position of a broken thread . As the mill rotates the threads form a tape about i in. wide, and the leasing apparatus slides down a See also:

post to coil the threads spirally upon the reel . \\"See also:hen the full length of warp has been made the mill is stopped, a half See also:beer lease is picked by hand from the divisions formed by the runners, and also retained upon pegs . The mill next reverses its direction of rotation, and as the leasing apparatus ascends the threads are folded back upon themselves . Hence, if a reel is 20 yds. in circumference, and 200 threads are in use to make a warp 60o yds. See also:long, and containing 2000 threads, the reel will make 3o revolutions (600-20=30) also 10 reversals, for at each reversal 200 additional threads will be added (2000=200=10) . When a warp is complete, strings are passed through the leases, and it is coiled into a See also:ball, loosely linked into a chain, or dropped into a See also:sheet . If a mill has its axis horizontal the leasing apparatus must slide horizontally . Winding on Frame.—After a ball warp has been bleached, dyed or sized, the half beers are laid amongst the See also:teeth of a coarse See also:comb to open out the threads to the necessary breadth, in which condition they are coiled upon a loom beam . Beath warping is the See also:system most extensively used in the cotton See also:trade . The creels for these machines have an See also:average capacity of about 600 bobbins, and are often V-shaped in plan . In each See also:leg of the V the bobbins are arranged in tiers of 16 to 20, and See also:row behind row .

The threads are drawn separately between the dents of an adjustable reed, then under and over a series of rollers; from here they are dropped amongst the teeth of an adjustable comb and led down to a warpers beam, which rests upon the surface of a drum . As the drum rotates the threads are drawn from the bobbins and wrapped in even coils upon the beam . On most of these machines mechanism is attached for arresting motion on the fracture of a thread, and also for accurately measuring and recording the lengths of warp made . When full, a warpers beam holds threads of much greater length than are needed for any warp, but they are insufficient in number . Thus: If 50o threads are in use, and warps of the above-named particulars are required, four similar beams must be filled (2000=500=4) and the threads from all are subsequently united . The See also:

chief parts of a beam warper may be used as a substitute for a mill warper, provided that mechanism be employed to See also:contract the threads to the form of a loose rope and coil them into a cylindrical ball, which will he subsequently treated as a mill warp . Or, one of these warpers may be furnished with parts which, when the threads are roped, links them loosely into a chain . Sectional warping is chiefly employed for coloured threads and its outstanding features consist in contracting the threads to form a ribbon of from 3 in. to 12 in. wide . This ribbon is coiled upon a block placed between flanges, and when completed is set aside until a sufficient number of similar sections have been made; after which they are slipped upon a See also: