Jacquard Weaving and Designing

by T. F. Bell

Fig. 100

Another method is to have two sets of card irons, one above the other; the border cards are hung on the lower frame, and the centre cards on the upper one. The centre cards will work in the usual way, and when the border is to be wrought the cards for it are taken round the centre set, which, of course, are taken off the cylinder. The rollers must be made to shift so as to direct the cards properly into their respective frames; the top frame is smaller than the bottom one, and farther out from the machine. If hooks and eyes are sewn on the first and last cards of these sets, the weaver can hook them together when a fresh pattern is required, so that the one set will carry the other round the cylinder. Then, by drawing a cord, the rollers should change position so as to direct the falling cards into the proper frame. The card irons are of the usual shape, and the distance between the upper and lower ones may be regulated by circumstances.

Another simple method is to have the card frame made with a double curve in it, as shown in [Fig. 100]. One set of cards hang in each of these curves, as at A and B. The set in the curve A can be wrought over as long as required; then these cards can be taken off the cylinder and the set at B put over it. One thing must be observed: that the frame and rollers be so placed that the cards can be guided into the receptacle B, and to do this there must be a considerable fall for the cards, so that for a loom with a low framing this might not be feasible. Otherwise, it is a simple method of arranging two small lots of cards, and if one lot is much larger than the other, let A be a narrow curve, and the small lot of cards hang in it, which will lessen the slant of the cards falling to B.

Although such arrangements as the foregoing are required where there is much machinery used, it is evident that for frequent changes they would take up quite too much time. Several machines have been made for the purpose of changing from one set of cards to another without having to move the cards. The principle of these machines is to have two cylinders, one at each side; one set of cards is placed on one cylinder, and the other set on the other cylinder, so that by working one or other cylinder, as required, either border or centre may be woven. No. 1 ([Fig. 101]) shows a plan that was tried some time ago, but did not work satisfactorily. The needles passed through a needle board at each side of the machine, as at A and B, and had small spiral springs fastened on them inside the needle boards. The border cards could be put on the cylinder at A, and the centre cards on that at B. The cylinder at A could be wrought as a single-acting machine till a change of pattern was required; then the cylinder at B could be brought into action, and that at A remain stationary and clear of the needles. The heads of the hooks were made heart-shape, as shown, and the blades of the griffe could revolve into the position shown by the dotted lines, so as to suit the working of the cylinder at B; this was effected by the weaver pulling a cord. This machine was given up, as it was difficult to keep it in order.

Another method is shown at No. 2 ([Fig. 101]), where there are two griffes—one at F, and the other at G; one cylinder works at E, and the other at D. Only one set of springs is required on the needles—behind the needle board E—as the spring of the hooks is sufficient to act in the opposite direction. When the cylinder D is working the lower griffe is stationary, and when the cylinder E is working the upper griffe is stationary. The cylinders and griffes are brought into action as required by suitable mechanism. This machine has not been considered sufficiently successful to make it worthy of being persevered with.

Fig. 101