Rieter

Winding of the bobbin

Index

Fig. 15 – The bobbin form

A roving bobbin is a cylindrical body with tapered ends (Fig. 15). It is created by building layer upon layer of parallel coils of roving on wooden or plastic bobbin tubes acting as package cores. To form the tapered ends, the height of the lift must be reduced after each layer has been completed. The roving bobbin is the ideal package form for supplying material to the ring spinning frame; when full, the bobbin carries a relatively large quantity of material, owing to its compactness; when empty, it occupies a relatively small volume, convenient for transport and storage.
The angle of taper of the ends is normally between 80° and 95°, and depends upon the adherence of the material. The angle is made as large as possible, so that as much roving as possible is wound onto the package. However, the angle must be small enough to ensure that the layers do not slide apart.