| 摘要 |
<p>A weft feeder (10) for pneumatic looms, comprising a fixed drum (12), a rotating disk (13) for winding on the drum a reserve of thread to be fed to the loom, and an electromagnetic stop element (16) for blocking the unwinding of the thread from the drum after the counting, performed by means of a photoelectric cell, of a preset number (n) of turns of thread. The electromagnetic stop element (16) comprises a permanent magnet (18) which cooperates with a fixed magnetic core (19) provided with an annular gap in which a hollow moving element passes (24); a winding is associated with the moving element, and an energization current flows through it. The moving element (24) supports, at its end, a thread stopping finger (17), and is fitted without contact engagement on a cylindrical extension of the fixed magnetic core (19); said moving element (24) is supported so that it can move axially with respect to the cylindrical extension. <IMAGE></p> |
