False twist spindle with auxiliary reverse-twist element

Claim 1

IN APPARATUS FOR PRODUCING STRETCH YARN WHICH INCLUDES MEANS ADVANCING YARN ALONG A PATH, FALSE-TWIST MEANS HAVING AN INLET END AND DISCHARGE END ADAPTED TO RECEIVE SAID ADVANCING YARN AND IMPART A FALSE-TWIST THERETO, HEATING MEANS LOCATED ALONG SAID PATH IN ADVANCE OF THE INLET END OF SAID FALSE-TWIST MEANS ADAPTED TO RECEIVE AND HEAT-SET SAID ADVANCING YARN, A TWIST-TRAP ELEMENT LOCATED AT THE DISCHARGE END OF SAID FALSE-TWIST MEANS AND ADAPTED TO ENGAGE SAID YARN AS IT ADVANCES ALONG SAID PATH TO IMPART A REVERSE TWIST THERETO, AND MEANS WITHDRAWING SAID YARN FROM SAID TWIST-TRAP ELEMENT; THE IMPROVEMENT WHICH COMPRISES AUXILIARY REVERSE-TWIST MEANS, LOCATED BETWEEN SAID TWIS-TRAP ELEMENT AND SAID WITHDRAWING MEANS TRANSVERSE OF SAID PATH, ADAPTED TO HAVE SAID YARN PASS ABOUT IT AS IT ADVANCES ALONG SAID PATH, SAID AUXILIARY MEANS BEING LOCATED NOT MORE THAN ONE-FOURTH OF THE DISTANCE FROM SAID TWISTTRAP ELEMENT TO SAID WITHDRAWING MEANS.