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The jacquard machine was introduced into England about 1818 and came into general use from 1824 to 1832. It was introduced into Scotland about 1824. Fig. 16 is a representation of the early form of jacquard, and of course intended for hand-loom work. Although the present machines for power-loom work are very different in make, nearly all the working parts as here used are to be found in different machines at present working, or still being made, though the best machine makers have adopted newer and better principles for fast working and withstanding wear and tear. Fig. 16a is a view of the interior of the machine. The working of the machine will be explained further on; only those parts that will not be given in the new machines will now be noticed. The griffe or frame for raising the hooks is lifted by the straps A, A, Fig. 16, which are attached to the pulleys B, B, and a cord C over a pulley on the same shaft as B, B, is attached to a treadle beneath the loom. As the weaver presses down this treadle the griffe is raised, and when the treadle is released the griffe falls of its own weight. The cylinder is moved out and in by the pulley E, fastened on the bent iron bar, attached to the frame which carries the cylinder, when the griffe rises and falls. D, D is a frame which lies in the turned-up portion of the hooks; only a few hooks are shown, and the outer bars of the frame. There should be a bar in the frame for each row of hooks. This frame rises up and down with the hooks, the turn on the ends of which must be of such length that when the frame is raised by the hooks lifted by the griffe, it will not be raised out of the turns on those that are left down. This frame is for the purpose of preventing the hooks from turning round, so that the turns on the upper end of them, as shown at A, A, Fig. 16a, cannot get out of position to be caught by the blades or crossbars of the griffe. The lower ends of the hooks rest on a perforated board as shown in Fig. 16a, and tail cords are looped on them and pass through the perforated board as shown. To these cords is fastened the neck of the harness. Machines with these perforated boards and frames to keep the hooks in position are still (1890) being made in Yorkshire. In Fig. 16a is shown a section through the spring box B. This box contains a spiral spring for each of the horizontal needles, the ends of which press against the springs, which allow them to yield or move back as the cards press on their points; but recover them again when the card is moved away by the cylinder. Similar spring-boxes are now used.

Fig. 16

It might be interesting to describe the various changes and attempted improvements that have been made on the original jacquard, but it would take up too much space, and many of them are of more historical than practical importance; some of them will be mentioned that may be interesting from a mechanical point of view, in connection with the descriptions of the machines, even though they have only been partially successful. Though a very different machine from what it originally was, the principle of the jacquard remains the same, and is not likely to be altered or superseded till a revolution takes place in the process of weaving.

Fig. 16a

A jacquard machine is simply a shedding motion by which a great variety of sheds can be formed; the larger the machine, or the greater the number of hooks it contains, the greater is the variety of shedding that can be produced by it.

If a jacquard is made small, with, say, from 16 to 48 hooks, it is called a dobby or shedding motion, and is used for working shaft mountings; but the ordinary jacquard machines have from 200 to 600 hooks, which have long cords, called the harness, connected to them, no shafts being required, as each hook has only a few cords tied to it, which can be raised independently of the others. The fewer the cords that are tied to each hook, the greater is the variety of shedding that can be made on the same number of warp threads, till, when there is but one cord to the hook, any thread or any number of threads can be raised independently of any of the others.

Jacquards may be divided into four classes—viz. single-acting, double-acting lift, double acting with double cylinders, and twilling jacquards; and besides these there are several other varieties made for special purposes. The single-acting is the real jacquard, and much the simplest machine. It has the disadvantage which all single-acting shedding motions have—viz. that one shed must be closed before the following one begins to open. This is on account of the same lifter having to open each shed; it must bring down the set of hooks that are raised, and then raise the next set.

This constitutes the true jacquard lift; and while it makes a clear shed, and is desirable for some purposes, it is generally considered the most imperfect form of shedding—that is, so far as the making of a good cloth is concerned. It is not suitable for making a heavy, well-covered cloth, nor for working at a high speed, 120 to 140 picks per minute being a very good speed to drive it.

A single-acting jacquard is a very simple machine, and when properly made should give very little trouble in working, particularly if the motions are properly set in relation to each other, and if such methods of working are adopted as will cause the least wear and tear on it.

In whatever way jacquards are made, the principle of working is much the same. There are a number of upright hooks set in a frame; attached to each hook is a horizontal wire or needle, one end of which is pressed upon by a spring, which keeps both it and the hook steady and in position, while the other end, or point, passes through a perforated plate, beyond which it projects about half an inch (see Fig. 16a). To lift the hooks there is a set of bars or knives arranged in a frame, just below the heads of the hooks; this frame is called the ‘griffe’ or ‘brander,’ and if raised would draw all the hooks up with it. What hooks will be lifted for each shed is regulated by perforated cards being pressed against the points of the needles. A perforation in the card allows the point of a needle to pass through and the hook to be raised; but where there is no perforation the card comes against the point of the needle, pressing it back, and holding the head of the hook clear of the blade of the griffe, so that the griffe will pass without raising the hook. It will thus be seen that any variety of shedding can be made by punching the cards to suit it. Fig. 17 shows one of the best makes of single-acting jacquards. One of the best methods of driving is shown in this and the following figure. The griffe is raised by means of the lever G, which is sometimes supported on a beam fastened to the roof or pillars of the shed, or it may be supported by an upright fastened on the frame of the loom. A portion of this upright is shown in Fig. 17, and as well as being fastened to the loom frame, it should be stayed to the top of the machine. One end of the lever is fastened by a link connection to the centre of the bar across the griffe frame, care being taken that the connection is so made as to draw up the griffe vertically, and not have any strain on the slide rods or spindles that are used for keeping the griffe horizontal when rising.

Fig. 17

The other end of the lever is connected to a crank on the crank-shaft of the loom by a rod, E (Fig. 17); also shown at A (Fig. 18), where the crank is also given.

Fig. 18

In hand-loom machines the griffe is frequently pushed up from below instead of being drawn up from the top as is shown in Fig. 17. The method of doing this is similar to that given for lifting the griffes of twilling jacquards.

F (Fig. 17) is called the cylinder or barrel, evidently taking its name from the round cylinders or barrels used in the old machines, but is in reality a square prism. It is made of wood, and perforated on each side with a set of holes—a hole for each needle in the machine; its use is to draw round the chain of cards and press each one against the needles, or horizontal wires, in the machine. In order to keep the cards firmly on the cylinder, flat steel springs are sometimes used, as shown, attached to the top rail of the frame which holds the cylinder; and there are also steel wires which pass down in front of the cylinder over the ends of the cards. These springs are useful when only a small number of cards is used and the machine driven quickly; with a large set of cards, where there is plenty of drag on them from their own weight, they are not necessary, and but seldom used; but they are in common use in the Yorkshire districts.

It will be seen from the illustrations (Figs. 17 and 18) that the cylinder hangs in a frame suspended from the top of the machine; this is called the swing or batten motion, to distinguish it from the horizontal or sliding motion which is shown at Fig. 20 (No. 1) and in Fig. 27. The swing motion is the simpler of the two, and is cleaner, requiring less oil; but the sliding motion is steadier, and does not swing the cards so much, consequently is more suitable when the cylinder has to travel quickly. The swing motion also requires the machine to be higher; with a slide motion the frame is usually cut off a little above the griffe.

The cylinder has to travel out and in when the machine is working, so that it may be turned round and bring a fresh card against the needles for each shot. There are many methods of accomplishing this, which may be divided into two classes—viz. independent motions, or those which are driven from the loom independently of the machine; and self acting motions, or those which drive the cylinder out and in through the rising and falling of the griffe. The latter are the simpler, but the former are much better, causing less wear and tear on both the cards and machine, as will be explained further on.

It will be seen in Fig. 18 that as the cylinder travels out it will be caught by the hook K¹, and turned round; the head or lantern of the cylinder is made of iron, as shown, so that the hook, or shears, will take a firm catch on it. To prevent the cylinder from turning more than one card at once, and to keep it steady so that it will always come in fair against the needles, it is held firm by a hammer pressed on it by a spring. This pressure is applied in different ways, one of which may be clearly seen in Fig. 17, and another in Fig. 27. When taking out the cylinder, or wanting to run it round quickly to draw over a number of cards, the hammers can be held up by a hook or sliding catch, which should be fitted to the machine for the purpose.

One of the best independent motions for driving the cylinder is shown in Fig. 17; and that shown in Fig. 18 is also a very good one for small machines, perhaps the most convenient that is made; but the former is much stronger. In Fig. 17 a connecting-arm from the frame of the cylinder is attached to the lever B. The connecting-arm should have a slotted joint, so that it can be made shorter or longer, if required, for the purpose of regulating the pressure of the cylinder on the needles.

The lever B is on a horizontal shaft, bracketed to the frame of the loom, or to the beams on which the machine rests; or some machines have bearings attached to their framing for it. There is, of course, a lever, as B, and a connecting-arm at each side of the machine. There is another lever on the end of the shaft, at right angles to B, which is connected with an eccentric on the crank-shaft of the loom by a rod, C, in the same way as the rod C is connected with the eccentric in Fig. 18. The eccentric can be set to bring the cylinder against the needles at any required time, independent of the lifting motion of the machine, which cannot be done when the self-acting motions are used. The larger the eccentric, the greater dwell the cylinder will have against needles. The method of working the cylinder in Fig. 18 is somewhat similar, and can easily be seen; but it will be observed that a good deal of pressure will be put upon the studs on which the cylinder frame, or batten, hangs, particularly when the cylinder is being pressed in, as this is effected by drawing down the lever L; however, in a light machine this does not matter much.

Fig. 19

The principal feature in this motion is the escapement apparatus for the purpose of disengaging the cylinder from its connection with the driving eccentric when it is required to turn some of the cards back. Fig. 19 (Nos. 1 and 2) shows this arrangement. The motion is not quite the same as that given in Fig. 18, but is on the same principle, and one may be easily understood from the other. In Fig. 18 the latch G comes out of the notch in the quadrant F, when the handle E is pressed close; the handle is on the lever D, having its fulcrum on the shaft N, and the quadrant F is connected to the eccentric rod C. The quadrant is loose on the shaft, and the lever is fast on it. Fig. 19 is a more convenient motion. The two halves of the handle A are held apart by the spring H, and this, through the hook B on the inner end of the handle, presses the latch or catch on the slide D into the notch on the quadrant C. The quadrant and handle are one piece, and are fast on the shaft E, and a lever F on this shaft is connected to the batten of the machine, in the same manner as shown by D and B in Fig. 18. When there are two or more machines, one of these levers would be required for each. The lever K is loose on the shaft E, and the rod G connects it with the eccentric, same as is shown by the rod C in Fig. 18. In No. 2, Fig. 19, the quadrant is left out to show clearly how the hook B acts on the slide D, and also to show the lever K on the shaft. The two halves of the handle, being pressed out by the spring, keep D in position, firmly pressed inwards; but when the handle is pressed the hook B presses the slide D outwards, leaving the quadrant free to pass up or down; and by pulling down the cord H (Fig. 18), which raises the shears K and K¹, the cards can easily be turned back by working the handle up and down, as the under shears will catch the cylinder and turn it the reverse way. The weaver must be careful not to jerk the motion and throw the cards off the cylinder or damage them; but a very little practice will enable anyone to turn them back quite easily and quickly. This motion answers very well for one, or perhaps two, small machines; for a 400 or 600 machine, or any smaller size working spottings, &c., it is very convenient, but when large mountings are required, as in 800 to 2400 machines, it is quite too weak for the work; even if made strong enough it would not be satisfactory, as the strength of spring that would be required to bear the strain and keep the catch in the notch would make it a very difficult matter to use the motion for reversing the cylinder. For heavy machinery the method of working the cylinder shown in Fig. 17 is far preferable, and separate motions for turning back the cards can be fixed on the machine. These will be explained further on.

Instead of the eccentric and crank for driving the cylinder and raising the griffe being as they are shown in Fig. 18, though a plan frequently in use, it is neater, and perhaps better, to have the eccentric at the back of the fly-wheel, and the fly-wheel either cast with one half solid, or have a plate fastened across two or more of the spokes, to which the connecting-rod can be attached with a bolt fastened in a slot. The amount of lift can be increased or diminished, either by shifting the top of the connecting-rod along the lever G (Fig. 17), or by increasing or reducing the throw of the crank at the fly-wheel.

Fig. 19a

Self-acting motions actuate the cylinder through the rising and falling of the griffe without requiring any special connection from the loom. One of the most convenient of these is that frequently used on hand-loom machines, and known as the S iron or swan-neck motion. It is shown in Fig. 19a (No. 1), and another form of it on a swing cylinder motion is shown in Fig 16. D is the swan-neck or S iron. In the groove in it a roller stud on the griffe frame travels, sliding in and out the cylinder A as the griffe falls and rises. E is the slide bar, which may be flat or round; if round, there must be some means of keeping it from turning in its bearings, which is generally accomplished by having a crossbar bolted across the two slide bars behind the machine.

No. 2, Fig. 19a, is a motion for the same purpose, but consists of a series of levers; and No. 3 is an arrangement of a similar nature. B is the fulcrum of the levers, or fast pin by which they are connected to the machine. C shows the attachment of the levers to the slide rod of the machine. A is the connection with the cylinder frame. As the griffe rises or falls it will easily be seen that the cylinder will be driven out or in.

The connecting-bar H is in two parts, slotted and bolted together at H to admit of regulating the position of the cylinder.

No. 4 is a motion on a different principle; it is a French motion. It will readily be seen that the cylinder is driven out and in by the toothed wheel, which is wrought by a rack on the slide rod E. This slide rod works outside the framing of the machine, as is common in the French machines. One point must be observed about these motions—viz. that they must have a certain amount of dwell at the bottom of the stroke, or when the cylinder is in. The reason of this dwell will be explained further on, but the method of obtaining it may be given here. In the swan-neck motion (No. 1), any desired dwell can easily be obtained at either top or bottom by the length of the slot that is in a vertical direction, as when the stud is passing through this portion of the slot no motion is given to the cylinder. In the lever motions Nos. 2 and 3, as well as in No. 4, the dwell is got by the levers or arms passing the centres; in Nos. 2 and 4 it is by the lever or arm H passing the back centre, which may be considered as a crank; and in No. 3 it is the short lever C passing the centre that gives the dwell.

Fig. 20

Fig. 21

Fig. 22

Fig. 20 is a view of the interior of a single-acting jacquard machine with the framework removed; only one row of hooks and needles are given, to avoid confusion. The blades or knives of the griffe, with a support running across their centres, are shown at B. A is the face-plate or needle board, sometimes made of iron, but better to be of hard wood. C is the spring-box, the detail of which is given in Fig. 24. E, E¹ are the hooks, and F, F¹ the needles. D is the grating through which the hooks pass, and are supported by it. It will be seen that the hooks and needles are arranged in rows of eight: a 400 machine would have 50 or 51 of these rows in it; 500 machines are usually arranged in rows of 10, and 600 machines in rows of 12. The hooks should be set perfectly upright or vertical, and should be close up against the knives, but not pressing against them. There should be a provision made for shifting both the grating and the knives, so as to admit of both them and the hooks being properly set in relation to each other; but if set correctly by the maker, which they should be, no alteration is necessary. A (Fig. 21) is a side view of four hooks and needles, with the ends of the knives of the griffe shown at a, a, a, a. When the machine is working the needles are acted upon by perforated cards cut from the pattern. Suppose we take plain cloth—that is, a pattern in which each half of the warp, or every alternate thread, is raised and sunk alternately; then, if the first card acts on all the odd numbers of the needles, and the second card on all the even numbers, this repeated would make plain cloth. Whenever a hook of the jacquard is to be raised a hole is cut in the card for the needle connected with that hook, and a card with all the even numbers of holes cut in it will cause the griffe to raise all the even-numbered hooks. Refer to b (Fig. 21), where the second and fourth holes are cut in the card. If the card is pressed against the needles, as at c, the first and third needles will be pressed back, and will push the first and third hooks back from their position—shown by the dotted lines—to the position in which they are shown in B (Fig. 21); but the second and fourth hooks are not moved, as their needles pass through the holes in the card. If the griffe is now raised, the blades or knives will pass the first and third hooks, but will lift the second and fourth; and if the odd numbers of holes are cut on the next card, the first and third hooks will be lifted when it is pressed against the needles, as shown at C (Fig. 21), thus making the cross-shed; and this explains the principle of working any pattern by the jacquard without taking into consideration the intricacies of mounting, &c. In C (Fig. 21), it will be seen that if the knives d, d were upright instead of slanting, they would come down on the heads of the hooks that are under them, but, being slanted, their lower edges pass the heads of the hooks, and press them away as the griffe descends. Sometimes, even with slanting knives, if there is much vibration in the hooks, or if the loom ‘bangs off,’ some of the hooks are liable to get under the knives and be ‘crowned,’ or bent down. To avoid this deep blades are often used, principally in double-acting machines, so that the lower edges of the blades will not pass the bottom hook, as shown at D (Fig. 21). This prevents any danger of crowning, but it darkens the machine a little—that is, makes it more difficult to see down into it if any of the wires require to be examined; it also requires the heads of the hooks to be somewhat higher above the heads of the needles than is necessary with the narrow blades. Another principle has been tried—viz. that of making the heads of the hooks as shown in Fig. 22, and using narrow blades. This effects its object well, but there is too much friction of the knives against the hooks, and the latter are liable to wear out too quickly. A good machine with firmly set hooks should work very well without these protections if it is steadily placed above the loom, and it is better not to be resting on the loom framing, if convenient to have it so. It will be seen from the foregoing explanation that the proper time, or, rather, the necessary time, for the cylinder to press against the needles is just after the griffe begins to rise. When the griffe is down the top edges of the knives should be 3/16in. or ¼in. lower than the turned points of the hooks, and before this edge rises up to the hooks those that are not to be lifted should be full back, or the cylinder should be close in, having the front of the head of the hooks 3/16in. or ¼in. behind the blades. The cylinder should have a short dwell in this position; and if it has a longer dwell it may assist to reduce the friction of the heads of the hooks against the knives; but if it has too great a dwell it may have to travel out and in too quickly to make up for the lost time, which will probably not be compensated for by the advantage of the increase in the dwell. Now, when the cylinder is driven with an independent motion, as in Figs. 17 and 18, it is easy to set the eccentric so that it can be brought in at any required time; but when a self-acting motion is used, it is plain that if the cylinder must press against the needles when the blades of the griffe are passing the heads of the hooks in rising, it must also press against them in the same position when the griffe is falling, unless some special escapement motion could be devised to avoid it, and this is where the dwell is required, and where the evil effect of the motion takes place; and it is worse in a double-lift machine with one cylinder, as the heads of the hooks in it are larger, or have a longer turn on them. A little consideration will suffice to show that when the brander or griffe is falling, say, with one-half of the hooks hanging on its knives, and the cylinder is brought in against the needles before the hooks are quite down, as it must be, it will either cause the hooks to be shot off the knives, or will put a considerable strain on them, as well as upon the needles and cards. It is for this reason that these motions are objectionable, particularly in power-loom work, where the speed is high and the hooks are strong. In hand-loom work it is not so objectionable, as there is more spring in the wires, and the heads of the hooks need not be too large, and, besides, the speed is less and the wear and tear not so great; but, even with this, if a hand-loom machine that has been in use for some time be examined, it will be seen that the points of the hooks are considerably worn, and that the edges of the knives are hollowed out like a coarse saw by the friction of the hooks on them. This latter will partly arise from the lifting of the hooks.

Fig. 23

In the old Jacquard, given in Figs. 15 and 16, the hooks are shown resting on a perforated board, and it was mentioned that in order to prevent them from turning round a frame lay in the turned-up portion of the hooks. The grating in Fig. 20, through which the turned-up bottoms of the hooks pass, readily accomplishes this object. Sometimes flattened hooks are used, as in C (Fig. 23), with the needles twisted once or twice round the hooks; this makes a firm arrangement, but if anything goes wrong with a hook it is not easy to get it clear of the needle. When the needles were made with a full twist or loop on them, as at B, the same was the case; they are now usually made as at A, and if arranged in the machine as in Fig. 20, there is no danger of the hooks sliding out of the recess in the needle, and if a hook gets bent or broken, it can be taken out and replaced by a new one without disturbing the needles.

Fig. 16 shows how the needles press against the springs in the spring-box, which is much the same as that at present in use. Fig. 24 is the present arrangement. No. 1 gives a plan of the end of a needle, B. C C is the horizontal wire which supports it as shown in section at C C in No. 2. D (No. 1) is a section of the vertical wire shown at D D (No. 2), which passes through the loops or eyes on the ends of the needles, and keeps the springs from shooting them too far forward. A (No. 2) is a wire which passes down at the outside of the box over the ends of a row of springs, so that by drawing out this wire any of the springs can be drawn out without taking off the spring-box, as the springs pass through the box. The springs should be strong enough to keep the hooks and needles steady, but if unnecessarily strong they give the card and cylinder unnecessary work.

Fig. 24

In some machines there is no spring-box. The hooks are made double, as shown in Fig. 25, and rods, as a, a, run along between the rows of hooks; the spring of the double wire keeps the hooks steady. There is a clap-board used, similar to that in the French draw loom, (Fig. 13), which is pressed against the needles with springs; this board is connected with the face-plate by a bar at each end, forming a frame. The needles do not project much through the face-plate, but when the cylinder is pressed against it, it slides back on the needles, and presses the clap-board back, which also allows those needles to go back which the card presses against. The needles are not looped on the hooks, but have a turned catch in front of them as shown. The bottom of the hook rests on a hole board, C, through which the tail cords pass; and through the hooks at D are wires fixed in a frame which rises and falls when the hooks are raised, and keeps them from turning round, same as explained in Fig. 15. Machines of this description are at present being made in France, and work with a rising and falling shed, which will be hereafter explained (see Fig. 30).

Fig. 25 Fig. 26 Fig. 27

In working, the card cylinder must be so set that it will come forward fair on the needles—that is, that when it comes forward the points of the needles will enter fair into the centres of the holes in it. For the purpose of setting it there must be provision made in the fittings so that it can be moved laterally or vertically. In the swing motion the frame can be moved laterally by means of the two screw studs on which it hangs. C, Fig. 27, shows the bearing on which the stud of the cylinder revolves. This bearing can be raised up or down in the frame R—a side view of which is given at S—by slackening the bolt B with the wing nut A, and adjusting the bearing with the set screw D or E.

A method commonly adopted by tacklers or tuners to see that the needles are perfectly fair in the centres of the holes in the cylinder, is to rub their fingers on some dirty oil, and touch over the points of the needles with it. They then bring in the cylinder against the needles with a card on it, in which about half of the holes are cut. The points of the needles mark the card where there are no holes, and it can easily be seen whether the mark is in the centre of where a hole should be, or not.

One of the best bearings and attachments for a cylinder with a horizontal slide motion is given in Fig. 26. D is the bearing for the cylinder E, and C the bolts for setting it. F F is the bracket which holds the hammer and bearings, which can be set in position on the slide bar B by the bolt A. I is the hammer held down by the spring H attached to the rod G.

The cards are kept in position on the cylinder by pegs or studs, originally made of wood, and driven into the cylinder. Now they are made of brass, and set in a slotted bracket, so that they can be shifted in order to have the holes in the cards corresponding exactly with those in the cylinder. The pegs should also be set on springs, so that if a card gets off them, and between them and the needle plate, they will yield or sink into the cylinder, and not break the card. In all good machines they are made in this way.

When the motion for driving the cylinder is not fitted with an escapement for the purpose of turning back the cards, it is necessary for the convenience of the weaver to have a motion on the machine for the purpose.

Fig. 28

Figs. 28 and 29 show two varieties of these motions. A is the cylinder head; C, the catch for reversing the cylinder; F, the spring for returning the catch to its position; E, a cord which hangs down, with a knob on the end of it, in a convenient position for the weaver to catch and work the motion. In Fig. 28 the motion is on the opposite side of the machine to the shears, but might be on either side, and the weaver has to raise the shears to turn the cylinder, which she can easily do by catching the knob for raising the shears in one hand, and working the reversing motion with the other. The cylinder must be full out for this motion to turn it properly, and this prevents the weaver from tearing the cards on the needles, as she might easily do by trying to turn the cylinder when it is too close in. In Fig. 29, B is the shears for turning the cylinder, and both it and the pushing catch, C, pass through a keeper or bracket, D, on the side of the machine. There is a rise on C a little back from the point, and when the cord E is pulled down C is shot forward by the lever, which has its fulcrum at G, and in going forward the rise on it comes into contact with the bend in the shears, and raises them up so that it can turn the cylinder when it catches on the head of it. Both these are good and convenient motions. For the latter the cylinder should be about half-way out when the cards are being turned back.

Fig. 29

Sometimes the cylinder may not be completely turned by the shears when the machine is working, by reason of the cards catching, or if the shears are too long, or it may arise from other causes. In this case the cylinder would come in with one corner against the needles, and be pressed heavily against the needle plate. Some of the levers would probably be broken, or the cylinder might be shot out of its bearings and fall, breaking the yarn, or perhaps injuring the weaver. To avoid this, small snecks, as at H, Figs. 28 and 29, are set so that when the cylinder is square it will pass over them; but if turned angularly its lower edge will catch on the point of the sneck, as the cylinder is coming in, and turn it square. The sneck is held up with a spring so as to allow the cylinder in turning to depress it. Sometimes the sneck, as at H, is liable to cause broken shots; for if the weaver turns back the loom, and the cylinder moves out sufficiently far to be turned to its angular position, and remains there, it will, in coming in, be turned square by the sneck, and thus a card would be passed over without a pick being put in for it. This is sometimes remedied by putting the sneck above the cylinder, instead of below it, which would turn it the reverse way; but this might come wrong at other times. The better plan is to keep it below, and let the weaver get to understand what she is doing, as it is not very difficult to learn.

The setting of a jacquard machine for working consists in adjusting the cylinder motion so as to bring in the cylinder at the proper time, and press it sufficiently close against the face-plate to keep the hooks clear of the knives of the griffe, without pressing it too close; and regulating the lifting of the griffe to suit the time for shedding, and to give the size of shed required. The shed must be open for the shuttle to pass through; the time for picking is when the cranks of the crank-shaft of the loom are at the bottom centre, therefore the shed should be almost fully open at this time. The lifting of the griffe can be made a little earlier or later to suit circumstances, but very little alteration can be made, as it takes a full revolution of the crank to raise and lower the griffe. Further consideration will be given to jacquard shedding after double-acting machines have been explained.

The motion for working the cylinder, if an independent one, should be rigid and strong; for if there is any spring in it, though the cylinder may be brought in sufficiently close when there is much cutting on the card, if a blank card or one with very little cutting on it comes on, the extra pressure on the needles, especially with a large machine, may prevent it from getting in sufficiently close to clear the hooks from the griffe. With self-acting motions there may sometimes be some trouble in this way, as the weight of the griffe may not be sufficient to press in the cylinder. In this case the griffe may be weighted, or may be allowed to drop quicker, or the lifting rod and lever may be made to assist in pressing it down somewhat.

Before starting the machine the needles should be examined to see that they are all free, and that they will spring out easily after being pressed back. The griffe should be perfectly horizontal and all the knives properly set; the holes in the cards and cylinder should exactly correspond, and when the cylinder comes in the needles should be fair in the centre of the holes; if not, the cylinder must be set as described (see description of Figs. 26 and 27).

The driving of heavy single-acting jacquards will be further considered under Twilling Jacquards.

When any of the hooks or needles in a jacquard get bent or broken, they can easily be straightened, or taken out and replaced by others. By putting a thin blade of iron or wood down through the needles alongside of the hook to be replaced, and springing open the passage, the old hook may be drawn out and a new one put into its place. The tail cord must, of course, be cut off the bottom of the hook, and a new one tied on. For changing a needle take off the spring-box and draw up the pin which fastens the row of needles at the back; then the needles in this row may be taken out till the defective one is reached, and the row made up again; or, the old one may be renewed without taking any of the others out. A flat blade is used to slide through the hooks and keep clear the place for the needle to be put in.

Card Frames.—The cards for jacquard work are usually hung on a frame as O, Fig. 18, wires sufficiently long to catch on both sides of the frame being tied to the lacing of the cards. The number of cards between each wire may vary to suit the space and the quantity of cards. Sixteen to twenty suit very well, the former for small and the latter for larger sets, and for very small sets twelve or fourteen might be more convenient. The frame may be made of round iron rod, or of flat or bar iron, and should be of the shape shown in the sketch, and not semicircular, as is usually the case, which presses the cards together in the centre; almost flat at the bottom, with just enough of a slope to make the cards slide back, is much the best. Of course, for a few cards it does not matter much what shape it is. P (Fig. 18) is the frame for the rollers over which the cards travel to the cylinder. They should be so sloped as to make the cards travel up nicely with sufficient drag on them, and not too much; on this depends a good deal the proper working of the cards, particularly when the machine is running at a high speed, and when springs are not used to steady them on the cylinder. It is usual to have a roller below the cylinder, attached to the frame which holds the cylinder, and the falling cards pass over it. Sometimes the cards, when falling, are shaken, so that some of the wires may not catch on the frame, but pass through it, or the ends of some of the wires may be bent and cause the same result; if the weaver neglects to put these up on the frame before the cards work round to those that have fallen, the wire may catch on it and prevent the cylinder from turning, or, perhaps, pull it out. Sometimes a crank or bend is made in the frame at the outer end, so that the wires can pass up through it without catching. The frame should just be sufficiently wide to enable the cards to pass freely through it with, say, one-eighth of an inch clearance at each side; then, if three or four inches at the outer end is cranked, or set out so as to be a little wider between the two bars than the length of the wires, they will pass up through without catching. Frames of the shape described are, of course, only suitable when the cards are to be wrought forwards—that is, with the cards falling between the cylinder and the machine; but if they require to be wrought both backwards and forwards, as is sometimes the case, the card frame must be made more of a semicircular shape, and the rollers must be set so as to give a sufficient fall to the cards, and keep them firm on the cylinder.

As has already been said, the nature of the shedding of a single-acting jacquard is objectionable for speed in working, for ease on the yarn, and for heavy work, or for well-covered work. The jacquard harness is levelled so that the yarn is all sunk, and the shed is entirely a rising one; it can easily be understood that when the griffe rises to open one shed, it must again fall before it can begin to rise to form the next shed. Now, mostly all tappet motions, and a great many dobbies or shedding motions, either have the yarn springing up and down from the centre, or have one portion rising and the other portion falling at the same time, so that in them the second shed could be open at the same time that the griffe in the single-acting jacquard had fallen to begin to rise the second shed; but as this would be much too soon, they can take a greater time to accomplish the work, and thus have a much slower and steadier motion.

It has been attempted to work the single-acting jacquard on the centre-shedding principle, and machines are at present being made in France of this class. It is only necessary to let the board on which the upright hooks rest fall at the same time that the griffe is rising in order to accomplish what is required, and the method of working is good, and would suit well in dobbies where the heddles can be taken firmly down. But in the jacquard the drawback is in the harness: the constant rising and falling causes a vibration in it, and does not admit of nearly so firm work as when the rising shed alone is used.

Fig. 30

One of these machines is shown in Fig. 30; they are a very compact and neatly made machine, and contain a much greater number of hooks than one of the English machines. Fig. 26 gives one of the hooks in this machine, and the way in which it acts is there explained. It will be seen that the frame for the cylinder is inverted; F is the face-plate or needle board as it rests when the cylinder is not pressing against it, being held in this position by the spring H pressing on a stud on the bar I, which extends from the face-plate to the clap-board G. The cylinder frame is driven by a rod, C, connected with a lever. E, E¹ are two racks on the ends of the hole board on which the hooks rest, and D, D are two levers with quadrant racks on each end, which work into the racks E and E¹, and also into the racks on the slide bar a1. This slide bar is fastened to the griffe A A, which is raised by a connecting-rod from a horizontal lever to the stud a. As the griffe is raised one end of the racked levers, D, is also raised, and the other end sinks, taking down the hole board by pressing on the racks E and E¹. The hole board is fixed so that it will easily slide up and down. If the griffe is raised two inches, the hole board falls rather more than one inch.

This is a very good motion, perhaps could not be surpassed for the purpose, but, as I said before, has the objection which all similar contrivances for the purpose must have—viz., causing too much vibration in the harness. All the cords constantly dancing up and down causes an unsteadiness and swinging that is not to be found in the ordinary jacquard harness. These machines have sixteen rows of needles in them, which are much closer set together than those in this country, and give a large number of hooks in a small-sized machine, which is a great advantage when extensive patterns are required. In this machine the half-card contains 440 holes, or 880 holes to the full or double card. The pitch is shown at A, Fig. 31, which represents the end of one of these cards, and a piece of one of the usual 8-row cards as here used is shown at B for contrast, the black dots in both cases representing holes.

These machines have not been adopted here, nor is it likely that they will be, although they are said to work well in France. They have been tried here, and the difficulty lay in setting the cards properly so as to act correctly on the needles, and keeping them so for any length of time. The least contraction or expansion of the paper, or any irregularity in the cutting, any bend in the points of the needles, or, in fact, anything but perfect exactness, interferes with the working: there is too great compactness in the machine, and in the ordinary wear and tear of work a little allowance is necessary for success. Considering that these are working, it would appear that the pitch and size of the holes in our cards are unnecessarily large, except where small machines answer and saving of space is no consideration; in that case the extra paper required for the cards might be more than compensated for by the strength of the machine, and the saving of trouble in attending to it.

Fig. 31

The method already mentioned of getting over the disadvantage of the single-acting jacquard is not likely to gain general favour, and is not required, as it is surpassed by the double-acting jacquard, or that in which there are two griffes, one rising when the other is falling, forming a counterpoise as well, making the shed more after the principle of ordinary tappet shedding. In a loom fitted with a single-acting jacquard, if there is much weight to be lifted, it will turn round the loom so that it will rest in no position but with the griffe down, and this is frequently of so much annoyance to the weaver as to necessitate a counterpoise being applied to balance it. Sometimes weights are used, and sometimes springs. With the double-acting lift nothing is required, and this was first used in Cross’s counterpoise harness (about 1816).

Fig. 32

Fig. 33

In the double-lift machine there are double the number of hooks that there would be in a single-lift machine of the same size, but the same number of needles; each needle is connected with two hooks, as shown in Fig. 32, which gives one row of hooks and needles for an 8-row or 400 machine. There are two griffes, one working above the other, as shown at A and B, Fig. 33. E, E is the top griffe in both; C, C is the bottom griffe, shown complete at A, but at B the side-bar of the frame is omitted, leaving only the knives to show how they fall in between those of the bottom griffe; D, D¹ are the two slide rods or spindles which keep the griffes steady in their traverse. There must be a sufficient space between the frame C of the lower griffe and that of the upper griffe, E, to allow of the required draw being given to form the sheds without them coming into contact. In these machines, although there are 16 hooks in the row, they only act as eight, so far as forming the pattern is concerned, as two hooks are governed by one needle; the additional hooks are solely for the purpose of obtaining a rising and falling shed. Each pair of hooks is connected together at the bottom by a piece of strong cotton cord, called the tail cord or tug cord, as shown in Fig. 35. The griffes are raised by two levers arranged side by side, and similar to the one shown in Fig. 17. These levers are wrought by rods connecting them to a double crank, or sometimes to a tappet, on the tappet shaft of the loom. The common form of crank is shown at A, Fig. 34. B is the tappet shaft, and on the end of it is fastened a disc. A second disc, which carries the double crank, G, is bolted against this one, and can be shifted to whatever position is required to give the tread at the correct time. The cylinder is driven from an eccentric on the crank-shaft as before described. One of the griffes rises for each shot, the other falling at the same time; but the cylinder must come in for every shot, and it is here that the principal fault in this machine lies. Not only has the cylinder to travel at a high speed, but when one griffe is at its highest position, it has to press against the needles, so as to clear away those hooks that are not to be lifted by the lower griffe, which should now be beginning to rise; and in consequence of the needles being attached to two hooks, one belonging to the upper griffe, and the other to the lower one, it follows that those needles that are pressed in by the cards have to spring back the hooks connected with them that are raised by the upper griffe, which is a severe strain on both needles and cards. To prevent the hooks being pushed off the upper griffe, they must have larger turns on them than would otherwise be necessary.

Fig. 34

Fig. 35 shows how the raised hooks can be allowed to yield to the pressure of the needles. A, B, C, D are four hooks connected with two needles, 1 and 2. When the hook A is raised, if B, which raises the same warp—as will be seen by the connection of the tail cords with the harness at E—is not to be raised for the next shot, the needle 1 is pressed back by the card, and presses the hook B back from its knife as shown, the dotted line being its original position; the A hook, being connected with the same needle, must also be sprung back, but its head cannot get back, as it is held on the blade of the griffe, so that the wire would require to spring, if some escape were not made for it. The lower ends of the hooks are made V-shape in the grating, so that when raised, if pressed on by the needles, they can move forward as shown, the dotted line showing the original position of the hook A. When the hooks fall, they fill the slots in the grating, and are thus kept steady. G shows the tail cords as connected with the harness when both hooks are down; E shows them when one hook is up and the other down, and if the hook B was raised for the next shot, the tail cord on it would be tightening up as that on A would be falling, and the harness attached to them would be caught up a second time from the middle position, thus forming centre shedding with any portion of the harness that is raised several times in succession. With plain-texture cards the upper and lower portions of the shed would pass each other in the centre when the sheds are being reversed, all the even numbers of hooks being on one griffe, and all the odd numbers on the other.

Fig. 35

Fig. 36

The tail cord consists of two pieces of cotton cord, one fastened to each hook of a pair, then the two ends are together tied to the bunch of neck twines that are to hang from these hooks, as shown in Fig. 35, and at A, Fig. 36. When one hook is raised and the tail cord drawn up with it, the other portion of the tail cord, which is tied to the other hook, is slackened—as shown at A, Fig. 36—which causes a certain amount of friction on them. Also, when one hook of the pair is falling with the descending griffe, and the other hook rising, the pluck occasioned thereby on the cords, when the hooks are passing at the centre, has a tendency to wear and break them. Although this does not occur when the lingoes are of a moderate weight (18 to 25 per lb.), and when only a few neck twines are tied to each tail, yet when a large number of neck twines (say 20) are tied to each tail, with weighty lingoes, as may frequently be the case in weaving small patterns on woollen and worsted goods, the breakage of the tail cords is a common source of complaint, which not only gives the trouble of renewing them, but is liable to cause defects in the cloth, by the weaver not observing the breakage for some time, as one hook of the pair may be raising the neck twines—that is, in case of the tail cord to only one of the hooks breaking. To remedy this Messrs. Hancock, Rennie, and Hudson have this year (1890) introduced a patent link connection for joining the tail to the hooks, which only requires one cord, or double cord, to be used, instead of two as before. This is shown in Fig. 36 at B. When one hook is raised and the other down, the link is in the position shown at C. The old method is shown at A. When one hook is rising and the other falling, the partial turning of the link causes a loss of time equal to about a quarter of an inch of lift, and this eases the sudden pluck on the tail cord. When both hooks are down there is also a loss of a quarter of an inch in the lift when one hook begins to rise, caused by the turning of the link.

Fig. 37

Fig. 38

This patent works very well, but, except when heavy weights are on the hooks, is not likely to supersede the older methods. These links are fitted to machines by makers in Manchester and Bradford.

Before the form of griffe shown in Fig. 33 was adopted the hooks were made of two heights, as shown in Fig. 37, and one griffe wrought above the other, instead of the one set of blades or knives passing through each other; but this method was given up on account of the vibration of the long hooks, which made it uncertain whether they would remain on the knives or keep clear of them when required. Fig. 37 shows this arrangement of hooks for a double-cylinder machine; for a single-cylinder machine with two griffes the heights of the hooks would be similar, but the heads would all be turned in the same direction, and the knives sloped to suit this, as is done when the hooks are all of the one height; each needle would be connected to a short hook and a long one. The short hooks give much more certain work, and can have the cylinder set so as to press back the hooks only as much as is required, whereas with long and short hooks allowance had to be made for the uncertainty of the vibration and the difference in the length of the two sets of hooks.

Fig. 38 is a view of one of the best makes of double-lift jacquards with a single cylinder.

The machine is made by Devoge & Co., of Manchester, but is not here given as being specially recommended in preference to others; it is only given as an illustration. Those wanting to buy a machine had better see what are in the market, and select what they consider most suitable to their work and price. This applies to all the machinery given in these articles. There is rarely a best machine for all purposes.

Fig. 39

These machines are much in use, and can be run at a high speed, say 160, or even 180, and by many are preferred to the double-cylinder machines, as there is no danger of one cylinder getting before the other, and the cards are all laced in one set; besides, it may be more convenient for working, as some arrange their machines so that the cards for one loom hang to the back, and those of the next to the front. When these machines are to work at a high speed, the slide-motion cylinder will probably be found the most satisfactory. Fig. 39 illustrates one of these machines with slide cylinder motion and the levers for driving it, the connections being as before given. The levers for raising the griffes are also shown, but here go to the back, whereas they are usually at the side.

The most perfect jacquard machine in the market is undoubtedly the