Cotton Weaving and Designing / 6th Edition

by John T. Taylor

FIG. 110.

The first hole cut in the card is operated with the little finger of the right hand. Following this hole to the loom, we find it operates the last or 400th end in the draft, and that the hole cut last on the card (numbered 400) operates the first end in the draft. This is the hole which operates the bottom needle in the last row on the “25-side” of the Jacquard machine, which, as was previously stated, is the hook from which the draft begins.

Following out the operation of cutting the card. When the 26th row has been cut, the lace holes MN ([Fig. 108]) are cut, and then the cutting is again straight-forward to the 50th row. The piano machine is so constructed that with the same stroke of the treadle which cuts the 51st row the peg hole D is also cut, and then follows a stroke without cutting, after which the two lace holes T and Y are cut. This makes 56 strokes of the foot for each card.

It is usual, in order to economise space, for the Jacquards with straight, or “Norwich,” harnesses to be placed on the loom, so that on one loom the cards hang over the weaver’s head, and on the next the cards are at the back of the loom. In both cases the harnesses are built the same way, but in one case (cards over weaver’s head) the thread operated by the bottom needle on the “25-side” will be at the back of the comber-board, at the left hand; and in the other case (cards behind loom) the same thread will be at the front of the comber-board at the right-hand side.

As previously stated, the single-lift Jacquard for cotton weaving is not often employed except for special purposes, such as figured leno weaving. The advantage possessed by the double-lift Jacquard as regards speed is so very considerable that its adoption for ordinary forms of cotton weaving has become universal; and the advantage of speed is not the only advantage it possesses, as will be pointed out shortly.

A double-lift machine with one cylinder for a 400 end pattern consists of 800 hooks and 400 needles. Each needle is twisted or bent round two hooks, as shown at [Fig. 111]. The hooks are connected together in twos by neck cords, which are usually strong whipcord, as will be seen from the illustration. It will be seen that the bottom needle is bent round the back pair of hooks, the next needle round another pair, and so on. Each needle has a spring behind it, as in a single-lift machine.

FIG. 111.

There are two griffes, which work oppositely—that is, as one goes up the other comes down. The griffes (or knives) are worked by a double crank on the bottom shaft of the loom, so that each griffe moves from the bottom to top of its stroke in one pick, and from top to bottom in another pick.