Apparatus for producing texturized yarns

Apparatus for draw-texturizing and heat-setting a thermoplastic preoriented multifilament yarn comprising:

• feed means to supply the preoriented yarn to a residual stretching stage;
• at least three yarn transporting means spaced from each other and operating at adjustably different rotating speeds, the second transporting means being driven at a higher rate of speed than the first transporting means to complete the residual stretching and the third transporting means being driven at a lower rate of speed than the second transporting means to permit heat fixing of the yarn running between said second and third transporting means under adjustable relaxation conditions;
• thermal treatment means located between said first and second yarn transporting means including a yarn guiding and flattening means, a yarn contact heater arranged to heat each single filament of the running yarn along one side thereof applied to the heater and unilateral cooling means following and thermally insulated from said yarn contact heater, said unilateral cooling means being arranged to quench each said single filament of the running yarn from its side opposite that applied to said yarn contact heater;
• and
• another heating means between said second and third yarn transporting means for heat-fixing the residually stretched yarn upon relaxation and self-crimping resulting from a differential shrinkage over the transverse cross-section of each individual filament.