Fig. 87.
Fabric Design Made on a Jacquard
Machine.
Those of the needles proper that are moved up into work are brought down again and form new loops by the stitch cams l and m, Fig. 86. The small triangular cams j and k are for clearing the needles when a very short stitch is being drawn by the stitch cams l and m.
How Needles Are Selected
Now to show how the needles are selected we will first refer to Fig. 89, which shows the needle proper at b and the auxiliary needle at a. The auxiliary needle has a joint in it as shown at h to permit the lower end e to swing to the position shown by the dotted line i.
Fig. 90 shows the auxiliary needles in position with the card cylinder and cards in place ready to push them up into operation. Those needles which it is desired not to operate at all, such as the needles at the end of the plate that may not be needed, are drawn down and the ends are turned down to the point where they are at right angles to the plate, as shown by the dotted line at i. When they are in this position the cards cannot of course push them up into operating position. The short nib that looks like a part of a needle, indicated at f, and the card cylinder shown at g are not a part of the mechanism under consideration, but are another method of needle selection which will be explained later.
Fig. 88.
o-Black; x-White.
Designs Shown in Fig. 87 Layed Out
on Cross Section Paper for
Cutting Cards.
Fig. 84 is a general view of the back of the machine showing a set of cards on the card cylinder ready for work. Fig. 85 shows the mechanism used to bring the cylinder with the cards into action. The cards and cylinder need no distinguishing mark as they should be easily recognized from what has gone before. The same thing applies to the auxiliary needles just above, part of which are turned down to the point where they cannot be put into operation.
Letter j indicates the end of the shaft upon which the card cylinder is mounted, and c is the elongated opening in which it moves up and down. This opening is on the same diagonal plane as the needle plates and has its duplicate at the other end which carries the other end of the card cylinder. The rocker shaft d is mounted just under the card cylinder and has two levers securely attached, the other ends of which are connected to the card cylinder shaft, one at either end. On the outer end of the rocker shaft d is another lever indicated by the letter e. This is connected to the camway h through the extension k. This camway is mounted in such a manner that it can be moved only in one direction, and that direction is up and down diagonally or on the same plane as the back needle plates.