Jacquard Weaving and Designing

by T. F. Bell

Fig. 19

The principal feature in this motion is the escapement apparatus for the purpose of disengaging the cylinder from its connection with the driving eccentric when it is required to turn some of the cards back. [Fig. 19] (Nos. 1 and 2) shows this arrangement. The motion is not quite the same as that given in [Fig. 18], but is on the same principle, and one may be easily understood from the other. In [Fig. 18] the latch G comes out of the notch in the quadrant F, when the handle E is pressed close; the handle is on the lever D, having its fulcrum on the shaft N, and the quadrant F is connected to the eccentric rod C. The quadrant is loose on the shaft, and the lever is fast on it. [Fig. 19] is a more convenient motion. The two halves of the handle A are held apart by the spring H, and this, through the hook B on the inner end of the handle, presses the latch or catch on the slide D into the notch on the quadrant C. The quadrant and handle are one piece, and are fast on the shaft E, and a lever F on this shaft is connected to the batten of the machine, in the same manner as shown by D and B in [Fig. 18]. When there are two or more machines, one of these levers would be required for each. The lever K is loose on the shaft E, and the rod G connects it with the eccentric, same as is shown by the rod C in [Fig. 18]. In No. 2, [Fig. 19], the quadrant is left out to show clearly how the hook B acts on the slide D, and also to show the lever K on the shaft. The two halves of the handle, being pressed out by the spring, keep D in position, firmly pressed inwards; but when the handle is pressed the hook B presses the slide D outwards, leaving the quadrant free to pass up or down; and by pulling down the cord H ([Fig. 18]), which raises the shears K and K¹, the cards can easily be turned back by working the handle up and down, as the under shears will catch the cylinder and turn it the reverse way. The weaver must be careful not to jerk the motion and throw the cards off the cylinder or damage them; but a very little practice will enable anyone to turn them back quite easily and quickly. This motion answers very well for one, or perhaps two, small machines; for a 400 or 600 machine, or any smaller size working spottings, &c., it is very convenient, but when large mountings are required, as in 800 to 2400 machines, it is quite too weak for the work; even if made strong enough it would not be satisfactory, as the strength of spring that would be required to bear the strain and keep the catch in the notch would make it a very difficult matter to use the motion for reversing the cylinder. For heavy machinery the method of working the cylinder shown in [Fig. 17] is far preferable, and separate motions for turning back the cards can be fixed on the machine. These will be explained further on.

Instead of the eccentric and crank for driving the cylinder and raising the griffe being as they are shown in [Fig. 18], though a plan frequently in use, it is neater, and perhaps better, to have the eccentric at the back of the fly-wheel, and the fly-wheel either cast with one half solid, or have a plate fastened across two or more of the spokes, to which the connecting-rod can be attached with a bolt fastened in a slot. The amount of lift can be increased or diminished, either by shifting the top of the connecting-rod along the lever G ([Fig. 17]), or by increasing or reducing the throw of the crank at the fly-wheel.

Fig. 19a

Self-acting motions actuate the cylinder through the rising and falling of the griffe without requiring any special connection from the loom. One of the most convenient of these is that frequently used on hand-loom machines, and known as the S iron or swan-neck motion. It is shown in Fig. 19a (No. 1), and another form of it on a swing cylinder motion is shown in Fig 16. D is the swan-neck or S iron. In the groove in it a roller stud on the griffe frame travels, sliding in and out the cylinder A as the griffe falls and rises. E is the slide bar, which may be flat or round; if round, there must be some means of keeping it from turning in its bearings, which is generally accomplished by having a crossbar bolted across the two slide bars behind the machine.

No. 2, Fig. 19a, is a motion for the same purpose, but consists of a series of levers; and No. 3 is an arrangement of a similar nature. B is the fulcrum of the levers, or fast pin by which they are connected to the machine. C shows the attachment of the levers to the slide rod of the machine. A is the connection with the cylinder frame. As the griffe rises or falls it will easily be seen that the cylinder will be driven out or in.