Rieter

Operating principle

Index

Fig. 3 – Working diagram

The roving bobbins (1) are inserted in holders (3) on the creel. Guide bars (4) guide the rovings (2) into the  drafting system (5), where they are drawn to their final count. The drafting system is at an angle of 45-60° and is one of the most important units on the machine, since it exerts a very considerable influence on the uniformity of the yarn in particular.

After the resulting thin ribbon of fibers (6) leaves the delivery roller, the twist necessary for imparting strength is provided by spindle (8) rotating at high speed. In the process each rotation of the traveler on  the spinning ring (10) produces a twist in the yarn.  Ring traveler (9) is also necessary for taking up this yarn onto a tube mounted on the  spindle. This traveler - a remnant of the flyer on the  roving frame - moves on a guide rail around the spindle, the so-called ring (10). The ring traveler has no drive of its own, it is dragged with spindle (8) via the yarn attached to it. The rotation of the ring traveler lags somewhat behind that of the spindle due to the relatively high friction of the ring traveler on the ring and the atmospheric resistance of the traveler and the thread balloon between yarn guide eyelet (7) and traveler (9).

This difference in speed between the spindle and the traveler results in the thread being wound onto the tube. In contrast to the roving frame, the ring spinning machine spindle operates with at higher speed than the traveller (9). The yarn is wound up into a cylindrical cop form by raising and lowering of the rings, which are mounted on a continuous ring rail. The layer traverse of the ring rail is also less than the full winding height of the tube. The ring rail therefore has to be raised slightly (shift traverse) after each layer has been wound. For a time, machines were also built featuring shift traverse produced by lowering the spindle bearing plate rather than raising the ring rail. These machines are no longer available today.