Size Effect of Interlacer

Abstract

In order to examine the size effect of an interlacer, we made several interlacers with different diameters of yarn duct and air jet nozzle. For these interlacers experiments were carried out on the number of tangles and the distance between tangling parts, and yarn motion was also measured by means of an optical fiber sensor system. Results obtained are as follows. (1) The optimum values of the yarn duct diameter d and the air jet nozzle diameter d'' which make the number of tangles N maximum exist, and then, the regularity of the distance between tangling parts is high. (2) When the diameter ratio Rd(=d/dn) is small or when the supplied air pressure p is large, a yarn stays near the duct wall opposite to the air jet nozzle and moves across the air jet axis frequently. However, the yarn scarcely opens, and a continuously blowing air jet destroys tangling parts which have been already made. When Rd is large, a yarn rotates for a long time inside each semicircle of the yarn duct divided by the air jet axis and scarcely moves across the jet axis. At a low supplied air pressure the air force is too weak to make many tangling parts. (3) Yarn motion is independent of the yarn speed v. With increasing v, N decreases because the period for a yarn to be subjected to an air jet becomes short. In the high yarn speed region, when Rd is small and p is large, a yarn can not enter the interlacer smoothly owing to strong air frictional force in the yarn duct, and finally breaks because of extremely high yarn tension. (4) In every interlacer, the yarn locus at the section of the air jet nozzle is a modified form of a number 8.