Manual and Cognitive Benefits of Two - Handed Input: An Experimental Study

This disclosure pertains to a broken wire switch for use in conjunction with a wire drawing machine. It includes a light source and a light detector, both mounted on the common side of the path of travel of the wire. The light source and detector are arranged so that the radiation pattern of the light source and the field of view of the light detector intersect at a point in the normal path of travel of the wire. An electric switch associated with the light detector interrupts the operation of a windup block that advances the wire.