GB1049953A - Improved process and apparatus for the crimping of yarns - Google Patents

Abstract

A stuffer box or the final chamber contiguous therewith has electric sensing means to determine the amount of yarn therein and to change the feed rate relative to the discharge rate, or vice versa, such that a substantially constant amount of yarn is kept between the feed rollers 2 Fig. 1, (not shown), and the exit of the final chamber. As described a nylon thread, yarn, or tow is fed by rollers 2 into a stuffer box chamber 4 formed by plates 5, 6 having central axial recesses 7, 8 and serrated auxiliary recesses 9, Fig. 2 (not shown), as in Specification 1,020,980 Chamber 1 has exit door 11 loaded by weight 13 while contiguous chamber 14 has spring-pressed door 15. Photo-resistor, photo diode, or photo-transistor is connected in a transistor circuit to the field coil of the motor of the winding-up device so that if the light beam from source 21 is interrupted by the end of yarn the motor is driven at a relatively high speed while if the light beam is not so interrupted the motor is driven at a relatively slow speed. The yarn &c., in chamber 14 is preferably substantially free from tension or pressure.