Yarn withdrawal apparatus and method

Apparatus for withdrawing continuously advancing yarn, comprising:

• a support,
• a tapered yarn winding roll rotatably mounted to said support and having a larger diameter end portion and a free smaller diameter end portion,
• means for introducing the advancing yarn substantially tangentially onto said roll, and with said roll having a surface which defines a cone angle which is greater than the angle of friction between the yarn and said surface of said roll, and such that windings of said yarn are adapted to be formed upon said larger diameter end portion thereof, and with said windings being continuously displaced along its length in the direction of said smaller diameter end portion thereof, and
• drive means mounted to said support for rotating said roll about a central axis at a rate such that the initial point of contact of the yarn upon said larger diameter end portion has a linear speed at least equal to that of the advancing yarn.

Apparatus for withdrawing continuously advancing yarn, comprising:

• a housing;
• a tapered yarn winding roll having a larger diameter end portion and an opposite free end portion of smaller diameter, said roll having a surface which defines a cone angle which is greater than the angle of friction between a yarn and said surface of said roll;
• bearing means mounting said roll within said housing for rotation about a central axis;
• yarn inlet means for introducing the advancing yarn into said housing and onto said larger diameter end portion of said roll;
• pneumatic drive means carried by said housing for rotating said roll about said axis at a rate such that its circumferential speed, at its point of initial contact with the advancing yarn, is at least equal to the delivery speed of the advancing yarn;
• said roll forming the advancing yarn into windings extending in helical fashion about said roll, and such that said yarn windings are displaced by and axially of said roll in the direction of said smaller diameter end portion thereof.

Apparatus for withdrawing a plurality of yarns advancing toward separated locations, comprising:

• a plurality of sequentially connected yarn withdrawal units;
• each of said units including a housing having a yarn inlet and a yarn outlet, a tapered yarn winding roll having a free end, means mounting said roll within said housing for rotation about a central axis, and drive means for rotating said roll about said axis;
• each of said units being adapted to receive a respective one of said yarns through said yarn inlet thereof, said roll of each said unit forming the yarn received thereby into windings extending about said roll and continuously displaced thereby toward and from said free end thereof, said outlet of said unit receiving the windings displaced from said free roll end;
• said units including at least a first unit and a second unit, said second unit having a passage extending therethrough, said passage interconnecting said yarn outlet of said first unit and said yarn outlet of said second unit such that the yarn withdrawn by said first unit and the yarn withdrawn by said second unit both pass to the yarn outlet of said second unit.

Apparatus for withdrawing continuously advancing yarn, comprising:

• a housing;
• a tapered yarn winding roll rotatably mounted in said housing and having a larger diameter end and a free opposite end of smaller diameter;
• drive means mounted to said housing for rotating said roll about a central axis;
• yarn inlet means for directing said advancing yarn into engagement with the tapered surface of said roll, said roll being adapted to form said yarn into windings extending about said axis and to continuously displace said windings axially toward said free end of said roll;
• and adjustable means for adjustively varying the location axially of said roll of the initial engagement between said advancing yarn and said roll, and for thereby adjustively varying the tension of said advancing yarn, said adjustable means comprising an annular jacket having entry means for guiding the yarn onto the roll, means mounting said jacket to said housing for movement along said central axis, spring biasing means for resiliently biasing said jacket axially toward said larger diameter end of said roll, and yarn guide means mounted to said jacket such that an increased yarn tension moves said jacket toward said free opposite end of said roll and against the force of said spring biasing means.

A method of withdrawing continuously advancing yarn, with the use of a rotatable tapered roll having a larger diameter end portion and a free opposite end portion of smaller diameter, comprising:

• (a) establishing contact between the roll and the yarn at a point upon the larger diameter end portion;
• while
• (b) driving the roll at a rate such that the linear speed of the point of initial yarn contact with the roll is at least equal to the delivery speed of the advancing yarn;
• (c) forming windings of the yarn about the roll;
• (d) continuously displacing the yarn windings along the length of the roll to and along its smaller diameter end portion, and including subjecting the windings upon the roll to a flow of air urging the windings toward and along the free smaller diameter end portion of the roll.

Apparatus for withdrawing continuously advancing yarn comprising:

• a housing;
• a tapered yarn winding roll having a larger diameter end portion and an opposite free end portion of smaller diameter;
• bearing means mounting said roll within said housing for rotation about a central axis;
• drive means for rotating said roll about said central axis;
• yarn inlet means for introducing the advancing yarn into said housing and onto said larger diameter end portion of said roll,
• said housing including a blind bore adjacent the free smaller diameter end portion of said roll for initially receiving yarn windings from said roll, duct means for withdrawing said yarn tangentially from said roll, and air jet nozzle means for generating an air flow in said housing from said yarn inlet means to said withdrawing duct means.