JACQUARD SHEDDING MECHANISM (TSCHORNER AND WEIN DAMASK JACQUARD):-

TSCHORNER AND WEIN DAMASK JACQUARD:-

This is another arrangement for weaving damasks. It is called 'damask' attachment’, and was patented by Tschorner and Wein.

Its construction differs from ordinary twilling Jacquards, but the same as shown a fig.137. It enable one weave to be worked on the ground, and another weave in the figure.

Fig.137. Tschorner and Wein damaskJacquard.

The griffe blade A and the twilling bar B , in separate frames, are lifted independently by rods. The rods are attached to jacks placed over the jacquard. These jacks are moved in one way by tappets at the side of the opposite direction the jacks are moved by springs. Both ends of the machine framing are slotted vertically in two lines so that projecting lips F from the griffe frame B pass through slots in the bottom line. By this means both sets of frames move vertically. Projecting lips F permit thise in one line to rest upon a twilling bar B. The needles K govern several hooks.

Each undisturbed blade A provides binding points for the figure, and each lifted bar provides binding points for the ground . The hooks E are made of sheet iron. The figure shows one of the knives left down , leaving down a row if hooks which would in the ordinary course have been lifted , and one f the bottom lifters is taking up a row of hooks which would in the ordinary course have left down. A card equal several picks . When a card operates , the cylinder remains away from the needles and stationary . 

A griffe blades can only operate vertical hooks , but when once lifted , all the griffe blades except, those for biding remain stationary, till a card is changed . In weaving an eight-end satin at least seventeen tappets are required, eight each for the griffe blades and twilling bars , and one for the cylinder.

HALF HARNESS:-

The foregoing are the chief kind of Jacquard and harness (except Leno’s) attached thereto. There are many combinations of shaft and Jacquard or mail harness. Mention may be made of a system, sometimes called ' half-harness .’ in which only half the ends are drawn through the jacquard harness, and the other half through shafts in front or behind . A double-sized figure may thus be formed in 'half-harness' system.

Inverted Hook Jacquard:-

In this Jacquard large figure are produced with ordinary forms of mounting and all the ends are controlled by the Jacquard mahine . Two series of ends , arranged in one-and-one order, work exactly opposite to ech other . An inverted Hook jacquard, which has two sets of hooks to one set of needles and cards , illustrated in fig. 138.  

Fig.138. inverted Hook jacquard.

This Jacquard has two sets of hooks A and B to correspond with the two series of ends . The hooks A faces the cylinder, wheres the hooks B face the spring box. A griffe D is used to operate all the 16 knives , having two sets of 8 knives each. Eight knives to operate ,8 hooks A are inclined towards the cylinder , and the other 8 knives are included towards the spring box to operate the hooks B . Normally, the hooks A rest over their lifting knives , but the hooks B are clear of their knives. 

The harness is mounted in the ordinary way, but one series of ends is drawn upon the harness cords connected to the hooks A , and the other series of ends is drawn upon the harness cords connected to hooks B as shown at E. One set of needles is used to operate the series of hooks A and B . Each needle C is connected to a hook of each series, and the operates an end of each series of hooks. If there is a blank in the pattern card , it will press away a hook A from path of the of the lifting knife and will place the corresponding hook B over the knife for being lifted . Again , if there is hole in the pattern card , it will leave a hook A over the knife for being raised and will keep the corresponding hook B out of action . It is now evident that when ends of the series of hooks A are lifted , corresponding series of ends of the series B are left down , and vice versa. This arrangement is very suitable for reversible warp rib other similar fabrics. 

Ref:-Weaving Mechanism Book Vol.1 by Prof. N. N. Banerjee.