GB874478A - Improvements in machines for crimping yarns by false twist - Google Patents

Abstract

874,478. Heating yarns by electric resistances. SOCITEX. June 20, 1958 [June 21, 1957], No. 19822/58. Class 39(3). [Also in Group IX] In a machine for crimping yarns by falsetwist in which each yarn passes through a heating-device before passing to a rotary spindle, a heating-device is provided for simultaneously heating a number of yarns comprising a block of good-conducting material serving as a heat-storage body of large heat capacity, enclosed in heat-insulation and having a corresponding number of yarn passages and at least one heating- element. The heating-device may comprise a single or composite block of aluminium weighing 60 kg.; in the latter case it may comprise a central plate 7a, Fig. 2, with vertical grooves in one face to receive tubes 4 constituting the yarn passages, and horizontal grooves in the other to receive electric heating-elements 8, the grooves being closed by plates 7b, 7c. The block may be enclosed as a loose fit in glass wool 8-10 cms. thick in a casing 13, Fig. 1, being held in place by the tubes 4, which are fastened in oblong holes by yarn guiding elements 5 but are free to move at their upper ends, where they are fitted with thread guides shaped as shown at 6 or tapering upwardly to remove residues from the yarns. To reduce the loss of heat by radiation in the extremities of the blocks they are cut off obliquely as at 12. A number of such heating devices may be arranged in one machine, being supplied by a transformer the primary of which is supplied through a voltage regulator. A temperature regulator controlled by a thermo-couple in one of the heating-blocks, which acts through a relay to cut-off the current when a given temperature is exceeded, and thermometers and temperature-adjusting potentiometers associated with each block are also provided. Specifications 824,492 and 874,477 are referred to.