Jacquard Weaving and Designing

by T. F. Bell

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.