| 摘要 |
<p>A web of textile fibers (2) is drawn in a draw frame (3), is transformed in a covering device (4) into a roving (5) by covering it with a fine continuous yarn; the roving thus obtained is then drawn in a draw frame (11, 12) of a spinning machine until the desired yam count is obtained. In order to avoid defects during the drawing of the roving and in order to avoid an exclusive utilisation of special continuous yams with reduced elongation for the covering, the continuous yams are tom not in the preparatory drawing area (11) of the drawframe, but in the main drawing area (12). To allow these operations to take place in perfect conditions, the continuous yam which is used for the covering must have a tensile strength of at least 10 cN for an elongation of 4% and a tensile strength of 100 cN; further, the ratio between the elastic elongation and the total elongation must not be smaller than 80% when applying a force of 15 cN. The covering device (4) is surrounded by a tilting protection allowing to remove as a whole the hollow spindle, the support and the bobbin with the continuous yarn. The rovings (5) are wound on a bobbin (7) by means of a driven cylinder (6) and transferred to a moving creel (9) which may be carried in the spinning machine where it will be fixed in a working position. </p> |
