Rieter

The grinding tools

Index

Fig. 137 – The full-width grinding roller

Fig. 138 – The traversing grinding disc

The full-width grinding roller

This has a drum with an abrasive sheet or, more generally nowadays, a coating of carborundum abrasive (Al2O3). The drum can be driven externally by a disc or internally by a motor within the drum. In the latter case, the tubular body of the roll forms the rotor. The grinding roller, in the form of the abrasive-coated drum, extends over the full width of the machine. Thus, the full width of the clothing on the operating elements of the card is treated simultaneously, which is very economical. On the other hand, if maintenance is poor, the drum can bend in the middle while revolving on the card. If this happens, the central portions of the main cylinder and doffer may be ground more than the edge zones. With modern grinding rollers the danger of this is minimal.

The traversing grinding disc

The grinding head (S), in the form of an abrasive disc 90 mm wide, can slide and is seated on a guide tube. It is driven back and forth over the clothing by a worm spindle in the interior of the tube. At any time it treats only a small portion of the total surface of the cylinder. Grinding takes far longer than with a full-width roller, but there is practically no danger of bending in the middle. In some equipment, the back-and-forth movement is not effected by a worm spindle but by specially driven belts. Drive is by individual motors.