Yarn false twisting method and apparatus

摘要

A method and apparatus of false twisting a yarn is disclosed which utilizes a pair of endless belts mounted in crossing relation to define a twisting zone therebetween, and a pressure applying member for locally biasing at least one of the belts toward the other at the twisting zone. The yarn is advanced along a path of travel through the twisting zone, and the acute angle formed between each belt and the yarn path of travel is adjusted so as to generally correspond to the desired twist angle of the yarn in its twisted condition. Further, the speed of each belt is adjusted so as to optimize the yarn tension conditions both preceding and following the belts. To achieve an essentially slipless operation, the pressure exerted by the biasing means is adjustably controlled so that the torque exerted by the belts exceeds the natural restoring torque of the yarn.