Semi-automatic piecing system on manually operated machines


The variations in mass, length and tenacity of piecings produced manually even by skilled operating personnel are so wide that they no longer satisfy international quality standards by far. This means that as a consequence of the inadequate piecing quality alone an otherwise high-quality yarn is not accepted and used in downstream processing.

This is why so-called semi-automatic piecing processes, which have significantly narrowed the gap in piecing quality relative to automatic piecings, have been developed for manually operated machines in recent years. Piecing after ends down essentially consists of the following operating steps (Fig. 61):

The only remaining manual operations are pulling the end of the thread off the package, cutting it to length accordingly and inserting it into the previously cleaned rotor through the draw-off tube.
Starting sliver feed to form the fiber ring in the rotor, subsequent yarn take-off from the rotor and start-up of the package are actuated under electronic control at the push of a button. A further special feature is that the fibers first combed out of the end of the sliver, some of which are damaged, are extracted when sliver feed commences, and fiber flow is only then diverted into the rotor.

Fig. 61 – AMIspin semi-automatic piecing system