Rieter

Fiber transport to the fiber collecting groove in the rotor

Index

The rotors, acting as fiber collecting and at the same time twist inserting elements, are the most important and also the most complex components in  yarn formation (Fig. 16). As already mentioned, in addition to yarn formation in the rotor groove, the fibers fed in are also separated from the transport air in the rotor, this air being dispersed either over the rotor wall (systems with indirect rotor bearing) or through holes in the base of the rotor (systems with direct rotor bearing).

Transfer of the fibers fed from the fiber guide channel into the rotor groove occurs via another intermediate stage, the rotor wall.
This feeding method is absolutely essential for orderly yarn formation. The peripheral speed of the inside wall of the rotor must be significantly higher than the speed at which the fibers are transferred to the rotor wall. This difference in speed ensures that the fibers encountering the inside wall of the rotor are accelerated to many times their transport speed. Since the fibers do not assume the peripheral speed of the inside wall of the rotor instantly on encountering it, they lag behind the slipping surface of the rotor wall and drift downward into the collecting groove in a helical line contrary to the direction of rotation of the rotor due to the slope of the rotor wall. The fibers are transferred neatly, arranged in the longitudinal direction, from the rotor wall to the rotor groove by the increasing centrifugal force of the widening inside diameter of the rotor in the direction of the rotor groove. The difference in speed between the fibers and the inside wall of the rotor also ensures that the fibers are extended in the longitudinal direction when they encounter the rotor wall, which in turn promotes the (desired) parallel arrangement of the fibers in the rotor groove.

Fig. 16 – Tangential fiber feed into the rotor and fiber transport to the fiber collecting groove of the rotor