Computer simulation of cone winding mechanisms with constant rate of yarn delivery systems

The work reported here is aimed at designing a tension compensation system that will prevent increased tension with increasing package diameter, which usually occurs with constant rate of yam delivery systems such as those us ed on OE spinning machines. Compensation is achieved by a feed-back tension monitoring device that adjusts the driving roller speed so as to keep the tension constant. In cone winding, the design of such a system is complicat ed by the fact that, at any particular driving roller speed, the yarn take- up speed varies from base to nose of the package and is only equal to the d riving roller speed at one point, the point of drive (POD). In order to sol ve this problem, a computer simulation of a cone winding system with consta nt rate of yam delivery is developed. The analytical work involved in creat ing the simulation makes it possible to determine the location of the POD a nd shows that it is dependent on yarn tension and on the frictional force b etween driving roller and package. This means that in designing the compens ating system, one must pay attention to the movement of the POD, which to s ome extent cancels out the effect of changes in the driving roller speed. T here is good agreement between experimental results and predictions derived from the simulation, and the new compensating system completely eliminates the effect of increasing cone diameter on yarn tension.