The twisting dynamic analysis of friction spinning

The theoretical analysis of twisting in the yarn formation zone of the friction spinning process is presented in this paper. By setting up and solving the twisting dynamic differential equation of the forming yarn that has a variable diameter and is undergoing a linear drawing movement along its axis direction, we obtained the distribution rules of the twist and the rotation speed of the friction-spun yarn in its formation zone. The analysis showed that the twisting zone of the forming yarn undergoing friction spinning consisted of three parts: the tip of the taper; the thick end of the taper; and the cylinder region. The yarn twist reached its maximum at the exit point of the yarn on the friction roller, and the emerging yarn from the friction roller did not obviously rotate.