Melt-spinning method and melt-spinning apparatus for producing a crimped yarn

Abstract

A melt-spinning method and a melt-spinning apparatus produce a crimped yarn. In this case, by spinning of a plurality of filaments, at least one filament bundle is generated from a thermoplastic polymer, is cooled and drawn and is compressed by means of an air stream in a stuffing chamber into a yarn plug, the yarn plug being opened up into a crimped yarn and being wound into a bobbin. So that the tendency to shrinkage and the crimp resistance on the crimped yarn can be set independently of one another, before compression, the drawn filament bundle is heated, in a first heat treatment for expansion, to a relaxation temperature and, in a second heat treatment for preliminary thermo control, to a crimping temperature. For this purpose, at least one further treatment means for the heat treatment of at least one filament bundle before entry into the stuffing chamber is provided between a drawing device a texturing device.

1 . A melt-spinning method for producing a crimped yarn, in which at least one filament bundle is generated from a thermoplastic polymer by the spinning of a plurality of filaments, in which, after cooling, the filament bundle is drawn and is compressed by means of a thermally controlled air stream in a stuffing chamber into a yarn plug, and in which the yarn plug is opened up into a crimped yarn and wound into a bobbin, wherein, before compression, the drawn filament bundle is heated, in a first heat treatment of expansion, to a relaxation temperature and, in a second heat treatment for preliminary thermo control, to a crimping temperature. 
     
     
         2 . The method as claimed in  claim 1 , wherein, for the second heat treatment, the filament bundle is guided in a plurality of loopings on a hot godet pair with heated godets. 
     
     
         3 . The method as claimed in  claim 1 , wherein, for the first heat treatment, the filament bundle is guided in a plurality of loopings on a drawing godet pair with heated godets. 
     
     
         4 . The method as claimed in  claim 1 , wherein the relaxation temperature for the expansion of the filament bundle is identical to the crimping temperature for the preliminary thermo control of the filament bundle. 
     
     
         5 . The method as claimed in  claim 1 , wherein the relaxation temperature for the expansion of the filament bundle lies above the crimping temperature for the preliminary thermo control of the filament bundle. 
     
     
         6 . The method as claimed in  claim 1 , wherein the relaxation temperature for the expansion of the filament bundle lies above the crimping temperature for the preliminary thermo control of the filament bundle, and in that the filament bundle is slightly drawn between expansion and preliminary thermo control. 
     
     
         7 . A melt-spinning apparatus for producing a crimped yarn, with a melt-spinning device, with a cooling device, with a drawing device, with a texturing device which has a conveying nozzle and a stuffing chamber, and with a winding device, the drawing device having a take-off godet pair and a drawing godet pair with heated godets, wherein at least one further treatment means for the heat treatment of at least one filament bundle before entry into the texturing device is provided between the drawing device and the texturing device. 
     
     
         8 . The apparatus as claimed in  claim 7 , wherein the treatment means is designed as a hot godet pair with heated godets. 
     
     
         9 . The apparatus as claimed in  claim 7 , wherein the drawing godet pair and the hot godet pair have in each case a heating control appliance, by means of which a plurality of godet heating means can be controlled. 
     
     
         10 . The apparatus as claimed in  claim 9 , wherein the heating control appliances are connected to a process control unit. 
     
     
         11 . The apparatus as claimed in  claim 7 , wherein the texturing device has a cooling drum for cooling a yarn plug guided out of the stuffing chamber.