Method of making retractile cords

Abstract

A plurality of groups of mandrels are arranged for movement successively through a plurality of workstations with each group being worked on at a station while other groups are being worked on simultaneously at other stations to produce continuously automatically groups of retractile cords. Cordage is fed from a supply into clamping engagement with each of the mandrels in the group in a cord-loading position and then wound helically in a plurality of spaced-apart convolutions on each of the mandrels of that group after which the wound cords are severed from the cordage supplies. The wound cords are advanced incrementally through a heating zone, wherein the cords are exposed to radiant heating supplemented by preheating of the mandrels, while cordage is being wound on the next successive groups of mandrels. The wound cords in each group are advanced through a cooling zone and then to an unloading station where they are removed from the mandrels while the pitch of the helices of the convolutions is reversed and the tendency of the convolutions to enlarge is minimized.