a process and apparatus for the winding of a thread onto a reel . a thread is guided by a thread guide fastened to a cord . the cord is driven by a drive part , which , under the action of a transfer roller engaging in a slot , executes a harmonic oscillation . a transfer roller is attached to a disc - shaped bearing part , driven by means of a driving wheel , and can , for changing the amplitude of the harmonic oscillation , be displaced in the radial direction by utilizing an electric motor . for the purpose of approximating the thread guide movement to a triangular oscillation , a heart - shaped compensating disc , likewise driven by the driving wheel , sets a carriage in oscillating movement synchronous to the harmonic oscillation , so that , due to displaceable pairs of rollers , which are mounted on the carriage and via which the cord is led , as also via fixed rollers lying between successive displaceable rollers , in each case the path of the cord is lengthened on one side of the traversing interval and correspondingly shortened on the other side .