AN ANNULAR CORE FOR A TOROIDAL COIL IS HELD IN A SHUTTLELESS WINDING MACHINE BETWEEN TWO ROLLERS ROTATED ABOUT FIXED AXES AND A THIRD, IDLING ROLLER MOUNTED ON A SPRING-LOADED ARM. THE CORE IS AXIALLY SECURED ON THE PLASTIC OR RUBBERCOATED ROLLERS BY FLANGES ON THE SAME, THERE BEING AT LEAST THREE FLANGES ON EACH ROLLER, EACH FLANGE BEING ALIGNED IN A COMMON PLANE WITH CORRESPONDING FLANGES ON THE OTHER TWO ROLLERS. THE FREE OF THE CONDUCTOR BEING WOUND ON THE CORE IS LED FROM THE CORE OVER ONE OF THE ROLLERS TO A SPRING-

LOADED CLAMP. THE SPRING TENSION ON THE ROLLER CARRYING ARM IS ADJUSTABLE, AND THE ARM MOVEMENT IS LIMITED BY A STOP.