METHOD AND APPARATUS FOR PREPARING A YARN PACKAGE FOR A SUBSEQUENT YARN RESTARTING OPERATION

摘要

A method and apparatus for preparing a yarn package for a subsequent yarn restarting operation are provided. The apparatus includes an air jet for directing a tangential stream of pressurized air against a yarn package to effect loosening of a length of auxiliary yarn which has been wound on the yarn package during a prior unsuccessful yarn restarting operation in which the auxiliary yarn length failed to piece with the yarn still to be wound onto the yarn package. The air jet operates in cooperation with a suction conduit to completely unwind the unsuccessfully pieced auxiliary yarn length from the yarn package to thereby prepare the yarn package for receiving another length of auxiliary yarn during a subsequent yarn restarting operation. According to one aspect of the invention, the auxiliary yarn travels over a roller supported at the free end of a delivery arm mounted on a traveling service unit and the roller is selectively disposable in rotation transmitting engagement with the lower roller of a roller pair of the drafting device to effect feeding of the auxiliary yarn onto the yarn package. If the auxiliary yarn has not successfully pieced with the still-to-be-wound yarn after a predetermined lapse of time, the roller on the delivery arm is positioned against an upper roller of a roller pair of the drafting device to effect unwinding of the auxiliary yarn previously wound onto the yarn package.