Spinning–twisting machine

The twisting of a fancy yarn can also be accomplished using a machine that combines the two processes, ring and hollow spindle.

In this case the first operation is carried out by the hollow spindle, preceded by the core and effect yarn feeding group. Below the hollow spindle, which holds the binding yarn, is located the ring spindle, which winds the yarn directly and the twists are loosened as an effect of the relative speed between the first and the second stages. Indeed, the ring spindle cannot rotate as fast as the hollow spindle and while this results in a softer yarn, the rate of production will inevitably be lower, given that the bobbin will also have to undergo a subsequent winding stage.
When the machine is fed with yarns rather than rovings, it becomes an out-and-out twisting machine (Figure 1).

When the effect is obtained by a roving, the machine must also effect drafting; this is why it is called a spinning-twisting machine (Figure 2)

The fed material is the roving (1) on spools, which is drawn by the laminating unit (A). The core yarns (4) are fed by the cylinders (C) and reach the exit from the drafting-laminating unit, where they are united with the effect yarn at point (D). Cylinder (5) is used for elastane, for the possible production of stretch fancy yarns. The binder yarn, positioned in the hollow spindle (E), stabilises the effect yarn, and the yarn, via the control cylinder (H), is then collected on the lower spindle (F), where the ring system evens out the twists. Using the handle (G), the operator can stop the spindle to repair breaks or replace the binder yarn package.
Fancy yarns can also be created by feeding more effect yarns, made up both of sliver in cans and of rovings on spools. In this case, the machine has two drafting lines (Figure 3), independently controlled, that make it possible to achieve a vast range of colour effects and constructions.