PURPOSE: To prevent accident when wire rod is drawn out positively from a supply reel by a roller mechanism to be sent into a processing line with a small resistance by detecting the slacked amount of the wire rod for stopping the processing line or giving an alarm when the above amount is lowered under a fixed level.

CONSTITUTION: Wire rod A is inserted between a pair of feed rollers 7 in a feed roller mechanism 6, and positively drawn out from a supply reel 1. The wire rod A slacked after passing through the feed roller mechanism 6, and then supplied to a processing line like a wire rod stretching mechanism 2 and others. When the slacking is increased over a fixed level, the feed roller mechanism 6 is stopped by the operation of a stop control switch 10 in a wire-rod slacking amount detecting mechanism 9 to stop the drawing-out of the rod wire A from the supply reel 1. Meanwhile, when the slacking is reduced under a reference level, a rotary arm is turned by the wire rod A, and a rotation control switch 13 is operated to restart the drawing-out. Besides, when a detecting switch 14 is operated, the line is stopped issuing an alarm.