GB566983A - Improvements in apparatus for heating filamentary material - Google Patents

Abstract

<PICT:0566983/IV/1> Filamentary material, e.g. filaments or bundles thereof of cellulose acetate, casein or those made from nylon, are heated, e.g. to dry them or during stretching or crimping, by forming a running course of the material containing sufficient conductive liquid to render it electrically conductive and inducing a high frequency electric current, e.g. of radio frequency, therein. As shown, filaments 2 from the spinneret of an artificial filament spinning machine are passed over two godets 3, 4, the godet 4 rotating at a higher speed than the godet 3 to stretch the filaments and the filament between the godets passing concentrically through a set of electrodes 5, 6, 7, of which the electrodes 5, 7 are earthed and the middle electrode 6 connected to one pole 13 of a high frequency oscillator 14, the other pole 15 of the oscillator is earthed. The electrodes are of ring form, or they may be gapped or of U form for facilitating threading of the filaments therethrough and the spacing of the electrodes may be varied to obtain the desired heating effect. Two electrodes may be used, each connected to a pole of the oscillator or the two outer of three electrodes may be connected to one pole and the centre electrode to the other pole of the oscillator. More than three electrodes may be used. Guides may be provided to maintain the material within the electrodes and the guide in advance of the first electrode may be arranged to wipe excess liquid from the surface of the filamentary material. The electrodes are formed of metal plates covered with glass.