Rapid cut-off apparatus for high speed moving yarn

Cut-off apparatus for rapidly cutting a yarn moving along a path therepast at high speed toward a yarn processing station when tension upon the yarn exceeds a predetermined tension, said cut-off apparatus comprising:

• a support means positioned to one side of the path of the high speed moving yarn;
• anvil means connected to said support means and projecting therefrom across said path and spaced from said yarn to provide a cutting surface in alignment with the yarn moving along said path;
• cut-off blade means having a cutting edge projecting therefrom across said path on the opposite side of said path from the cutting surface of said anvil means, said cut-off blade means being movably connected to said support means between an inoperative position spaced from said yarn and an operative cut-off position in engagement of said cutting edge against said cutting surface of said anvil means, said cutting edge frictionally engaging said yarn and forcing it against said cutting surface of said anvil means to sever it in the course of moving from said inoperative position toward said operative cut-off position;
• yarn guide means movably connected to said support means between an operative position extending across said path of said yarn for engaging and guiding said yarn toward said yarn processing station and to an inoperative non-yarn guiding position away from said path of said yarn, said yarn guide means being located upstream of said path of said yarn from said anvil means and said cut-off blade means;
• and
• over-the-center spring means having a predetermined tension and connected at one end to said cut-off blade means and connected at its other end to said yarn guide means, said spring means being shiftable between (a) a first position for holding said cut-off blade means in said inoperative position and said yarn guide means in said operative position and (b) a second position for moving said cut-off blade means to said operative cut-off position, said yarn guide means being forced by said yarn in engagement therewith to said inoperative nonyarn guiding position upon tension on the yarn exceeding the predetermined tension of said spring means and thereby shifting said over-the-center spring means to said second position in the course of its movement to said inoperative non-yarn guiding position.