PURPOSE: To cut off the blowing of quenching fluid simultaneously with yarn breaking, and to climinate the disturbance of the extruced filament yarn, by interlocking the flow rate regulating means of yarn quenching fluid with yarn breaking detector.

CONSTITUTION: The filament yarn Y, e.g. polyester, etc. is extruded from the spinning pack 11, and crosssectional anisotropy is imparted to the yarn Y by quenching its one side with quenching fluid blown from the quenching device 12 in one direction. The yarn Y is then oiled by the oiling device 20, and taken up by the take-up 23 via the godet rolls 21. If the yarn Y is broken to lose its tension, the dancer roller 24 is lowered to depress the limit switch 25 at the position B. The solenoid value 26 is operated by the signal from the switch 25 to close the valves automatically, thus stopping the quenching fluid from flowing.

USE: Spinning synthetic fibers having latent crimpability.