Rieter

Function

Index

Together with the cylinder (Fig. 107, 1), the flats form the main carding zone. Here, the following effects should be achieved:

  • opening of tufts into individual fibers;
  • elimination of remaining impurities;
  • elimination of some of the short fibers;
  • untangling neps (possibly their elimination);
  • dust removal (3);
  • high degree of longitudinal orientation of the fibers.

In order to fulfill all these requirements, a large continuous carding surface is needed. The surface is created by a large number of individual clothing strips secured to the bars of the flats (2) and arranged in succession. 40 to 46 such strips are commonly used (30 in Trützschler machines) to make up the carding surface in the operating position. Since elimination of waste can be carried out only by filling the  clothing, the flats must be cleaned continuously. They must therefore be moved past a cleaning device (4) (hence the name 'revolving flat cards'). The bars of the flats must be joined together to form an endless, circulating belt, for which purpose they are fixed to chains or toothed belts. In addition to the 40 - 46 flats (2) (Rieter  C 60 card: 27 flats) that interact with the cylinder (1), further flats are needed for the return movement on the endless path, so that altogether 100 - 120 flats (Rieter 79) are fitted to the rotating chains.

Fig. 107 – Carding zone between cylinder and flats