Takeout of Yarn End from Spandex Package with the Aid of Lashing End

Abstract

It is difficult to handle a fine spandex yarn which has extreme flexibility and high elasticity If a yarn end is lost. an operator has to peel the surface layer from the package to search for the required yarn end This process causes time loss yarn wastage. and lowers yarn quality Various methods for taking out the yarn end from the spandex package without a manual peel-off operation are investigated The yarn end rotates in a constant radius around the package when the rotating yarn breaks in the process of spinning. winding and covering In this time, the yarn shape under rotating is called lashing-end curve and the distance from the rotating center to the yarn end is called lashing-end radius. As a result. a method of taking out the lost yarn end by making the lashingend is proposed. Although there are some experimental analyses of the lashing-end for several yarns,the lashing-end radius is related to the linear density of the yarn, the package radius, the air drag coefficient and the yarn diameter. It is confirmed that the theoretical and experimental equations of these yarns are applicable for spandex yarn. In addition, an automatic open-and-close chuck using a rotational torque of motor and an apparatus for charging the package without gripping the surface of the package are designed and developed. Therefore. it is technically foreseeable to make a full-automatic system for the covering machine by combining these apparatuses and an auto-doffer