Automatic Yarn Winder

Overview

An automatic yarn winder rewinds yarn from the small bobbins that come off spinning onto large cones holding many kilometres of thread. The cone is the package that knitting and weaving machines want: it holds far more yarn, so a machine runs longer between changes, and it is wound so the yarn pulls off cleanly at speed. Winding is also the point where the yarn is cleaned, since the running thread is scanned and every fault is cut out and spliced over.

So the machine does two jobs at once. It builds a stable, dense, cross-wound package, and it improves the yarn that goes into it. The wind pattern matters because a poorly built cone collapses or sloughs off in coils; the clearing matters because a single thick slub or weak place would otherwise stop the next machine.

How it works

Yarn leaves the supply bobbin at the Supply Holder & Tensioner, where a disc tensioner and a balloon breaker pull it off under steady tension. It then runs past the Clearer & Splicer, whose sensor head measures yarn diameter continuously; when a thick place, thin place or foreign fibre exceeds the set limits, the clearer cuts the yarn, and an air splicer rejoins the two ends into a knot-free joint.

The cleaned yarn reaches the Traverse Mechanism, the heart of the machine. A grooved drum does two things together: its surface presses on the package and drives it by friction, while the crossing groove guides the yarn back and forth across the package face. That crossing lay is what makes the cone stable and lets it unwind over-end later. An anti-patterning device nudges drum speed now and then so coils never stack into a ribbon that would distort the package.

The package is held against the drum by the Winding Spindle cradle, which swings away as the cone grows. Power comes through the Drum & Spindle Drive, a belt and gear set off the drum motor. On its way the yarn brushes the Waxing Unit disc, picking up a film of paraffin that eases its later run. The Winder Control runs the head: it counts wound length, manages the clearing and splice cycle, and doffs the package at the set size.