Yarn tie-up and transfer tail method, and yarn package tube and apparatus for the method

Method of forming a yarn transfer tail on a yarn package tube that is supported on a rotating mandrel of a yarn winder, the yarn moving continuously from a source of supply to the yarn package tube for engagement with a portion of the surface thereof and away from the tube, as into an air doffer, the portion of said surface to be engaged rotating in the same direction as the direction of yarn movement;

• the supported yarn package tube comprising:
• (a) a substantially cylindrical body having formed in its external surface adjacent one end thereof a groove defined by a pair of side walls extending into the surface of the cylindrical body and extending at least partly around said cylindrical body in a plane substantially perpendicular to the rotation axis of the tube, and
• (b) the cylindrical body also having a corner formed in one of the groove side walls intersecting at an angle with said one side wall of the groove and pointing generally in the direction of intended rotation of the tube and adapted in rotary winding operations, as a yarn enters the groove in one direction of movement, for snagging a portion of the yarn exiting from the groove and deflecting said yarn around said corner for changing the direction of movement of the exiting yarn portion as said corner rotates with said tube away from where the yarn approaches said surface portion of the tube;
• the method comprising:
• (1) positioning the continuously moving yarn so that the yarn moves into engagement with said surface portion of the rotating supported yarn package tube in a partial arch at an initial location along the tube length that is away from and out of contact with the groove and said corner;
• (2) guiding the yarn sideways along the surface of the rotating yarn package tube toward the groove and said corner until the yarn drops into the groove and the exiting portion of the yarn engages said corner and becomes snagged and deflected therearound for changing the direction of movement of the exiting portion as the corner rotates with the tube away from where the yarn approaches said surface portion of the tube, and thereby tying-up the yarn to the tube and subsequently snapping and severing the yarn from the yarn going away from the tube;
• (3) winding the continuously moving yarn, as tied-up to the rotating supported tube, into a number of wraps to form a waste bunch;
• (4) winding the continuously moving yarn into a number of spaced apart helical wraps to form a transfer tail adjacent the waste bunch;
• and
• (5) thereafter winding the continuously moving yarn into a yarn package adjacent the transfer tail.

Apparatus for forming a yarn transfer tail on a yarn package tube that is supported on a rotating mandrel of a yarn winder, the yarn moving continuously from a source of supply to the yarn package tube for engagement with a portion of the surface thereof and away from the yarn package tube, the portion of said surface to be engaged rotating in the same direction as the direction of yarn movement, the yarn winder having a self-threading yarn traverse guide reciprocating along a path parallelly spaced from the package portion of the yarn package tube, the supported yarn package tube comprising:

• a. a substantially cylindrical body having formed in its external surface adjacent one end thereof a groove defined by a pair of side walls extending into the surface of the cylindrical body and extending at least partly around said cylindrical body in a plane substantially perpendicular to the rotation axis of the tube, and
• (b) the cylindrical body also having a corner formed in one of the groove side walls intersecting at an angle with said one side wall of the groove and pointing generally in the direction of intended rotation of the tube and adapted in rotary winding operations, as a yarn enters the groove in one direction of movement, for snagging a portion of the yarn exiting from the groove and deflecting said yarn around said corner for changing the direction of movement of the exiting yarn portion as said corner rotates with said tube away from where the yarn approaches said surface portion of the tube;
• the apparatus comprising:
• means for positioning the continuously moving yarn in engagement with said surface portion of the yarn package tube in a partial arch at an initial location that is away from and out of contact with the groove and said corner;
• said positioning means including means for guiding the yarn sideways along the surface of the rotating yarn package tube toward the groove and said corner until the yarn drops into the groove and the exiting portion of the yarn engages said corner and becomes snagged and deflected therearound, thereby changing the direction of movement of the exiting yarn portion as said corner rotates with the tube away from where the yarn approaches said surface portion of the tube, and consequently tying-up the yarn to the tube, and subsequently snapping and severing the yarn from the yarn moving away from the tube;
• and said positioning means also including means guiding the continuously moving yarn, as consequently tied-up to the rotating supported tube, to form a waste bunch of a predetermined number of wraps and a transfer tail of a predetermined number of spaced helical wraps adjacent to the waste bunch, with subsequent release of the guided yarn to be picked-up by said yarn traverse guide for guiding the yarn as the yarn package is wound.