Apparatus and method for producing false twist in yarn

Claim 1

APPARATUS FOR IMPARTING A FALSE TWIST TO A SINGEL END OF THERMOPLASTIC FILAMENTARY YARN, SAID APPARATUS COMPRISING: A FRICTIONALLY-SURFACED ROLLER MOUNTED FOR ROTATION ON ITS AXIS; DRIVE MEANS, INCLUDING POWER MEANS COUPLED TO SAID FRICTION ROLLER FOR DRIVING SAID ROLLER ROTATIONALLY, FOR PULLING SAID SINGLE END OF THERMOPLASTIC YARN ALONG A HELICAL PATH OVER THE SURFACE OF SAID FRICTION ROLLER FOR A DISTANCE OF AT LEAST 90* FOR TWISTING SAID SINGLE END OF YARN; TWIST BARRIER MEANS IN THE YARN PATH UPSTREAM FROM THE FRICTION ROLLER; HEATING MEANS AND A COOLING ZONE IN THE YARN PATH BETWEEN SAID TWIST BARRIER MEANS AND SAID FRICTION ROLLER FOR SETTING THE TWIST IN SAID YARN; AND GUIDE MEANS DOWNSTREAM FROM SAID HELICAL PATH OF SAID YARN ON SAID FRICTION ROLLER FOR GUIDING SAID YARN AROUND SAID FRICTION ROLLER IN WRAP-AROUND FASHION AND FOR CAUSING SAID FRICTION ROLLER TO PULL SAID YARN ALONG SAID HELICAL PATH.