Rieter

Classification

Index

Fig. 128 – Rieter card leveling system

Irregularities can actually be compensated:

  • in the material supply system;
  • at the feed;
  • at the delivery

as shown in Fig. 128 of the Rieter card leveling system.

The material supply should operate with the greatest possible degree of accuracy in any case, since this has a direct effect on sliver evenness. It is therefore not surprising that more and more card manufacturers offer the double-chute system with a degree of coarse regulation in the lower chute section. However, the main regulating position is the feed; adjusting the feed roller speed (5) usually performs autoleveling. Virtually all autoleveling devices exploit this possibility; adjustment of the delivery speed is hardly ever used. A distinction should also be drawn between:

  • short-term leveling systems, regulating lengths of product from 10 - 12 cm (rarely used in carding);
  • medium-term leveling systems, for lengths above about 3 m;
  • long-term leveling, for lengths above about 20 m (maintaining count).

In addition, regulating can be performed by open-loop or closed-loop control systems (see  Technology of Short-staple Spinning).