Device for applying auxiliary film to slide fastener chain

Abstract

An auxiliary film is applied or fused to a slide fastener chain having a pair of intermeshing rows of coupling elements with an element-free space defined therein. The slide fastener chain is fed by a chain feeder along a feed path. The device for applying the auxiliary film includes an ultrasonic horn disposed above the feed path, a holder disposed below the feed path and movable toward and away from the ultrasonic horn, a stopper disposed in the holder and movable into the element-free space of the slide fastener chain, an anvil disposed in the holder and movable toward and away from the ultrasonic horn, and a feed roller assembly for supplying an elongate auxiliary film onto the anvil. A sensor roller is mounted on the holder for pressed engagement with the elongate auxiliary film, the sensor roller having a plurality of circumferentially equally spaced controlling elements. A controlling element sensor is disposed near the sensor roller for sensing the controlling elements one at a time and issuing a command signal to keep the chain feeder energized insofar as the controlling element sensor successively senses the controlling elements.