| 摘要 |
<p>A drafting frame includes a drafting unit for drafting a plurality of slivers running in an advancing direction and combining the slivers into a single sliver; and a sliver guide situated upstream of the drafting unit. The sliver guide has converging walls defining a cavity for guiding therein the plurality of slivers which are gathered by the cavity in a side-by-side orientation in a single plane. A sensor element is supported for displacement relative to the sliver guide. The sensor element has a sliver-contacting face movable toward and away from a counterface forming part of the cavity wall and defining therewith a constriction of the sliver guide. A force urges the sliver-contacting face of the sensor element towards the counterface to compress the slivers running through the constriction. A transducer is coupled to the sensor element for emitting a signal representing excursions of the sensor element in response to thickness fluctuations of the slivers running through the constriction. Further, a pull-off roll pair is situated downstream of the sliver guide and upstream of the drafting unit. The pull-off roll pair which defines a nip between which the slivers pass, pulls the slivers from the sliver guide.</p> |
