It will be seen in Fig. 18 that as the cylinder travels out it will be caught by the hook K^1, 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.
