Yarn feeder with rotary drum for textile machines

摘要

A shell (12) has a motor (18) housed therein, which is provided with a driving shaft (20) having a yarn-winding drum (22) mounted thereto. A lever (28) hinged to the shell (12) is slidably engaged by the yarn (F). Return means (42, 44) bias the lever (28) toward a stop position, in which it deviates the yarn coming from the drum (22) with respect to its feeding direction to a downstream machine. The lever (28) is subject to swing in contrast to the return means (42, 44) in relation to the variations of tension of the yarn (F). Sensor means (46, 48) detect the movements of the lever (28) with respect to the stop position and generate a corresponding activation signal. An electronic circuit (50) is operatively connected to the sensor means (46, 48) and is programmed to activate the motor (18) to unwind yarn in response to the activation signal.