Abstract: Catch yarns are drawn between a pair of rotatable members which are mounted to be movable toward and away from another and yieldably urged to come together. Detecting means detects the relative movement between the pair of rotatable members and produce an alarm-signal when the relative movement of one rotatable member away from another reaches a predetermined increased value.The catch yarns in tensioned state are further utilized to hold the detecting means at a rest position thereof. The detecting means also produces an alarm-signal upon the breakage of the catch yarns.

Abstract: A floating electrode is positioned in the nip between a pair of tape pull rollers on a needle loom for sensing the presence of excess yarn in the nip caused by improper winding of the tape on a take-up roll or a wrap around one of the pull rollers to an undue extent. Upon contact of the electrode by the excess yarn, the electrode is raised to contact a screw to establish an electric circuit to a relay to stop operation of the loom. The distance between the contact screw and electrode is adjustable by threading or unthreading the screw in its support to accommodate acceptable slack on the take-up roll and wrap around the pull roller.