Method and apparatus for modifying textile fabrics

Abstract

Abstract The dimensions of a fabric composed of yarns consisting of or containing thermoplastic material are modified by engaging spaced points along the boundaries of the fabric by means of holding members while continuously moving the fabric in a longitudinal path, bringing the members into effective distances defining the desired final dimensions of the fabric along a portion of its path, heating the fabric to its softening point along that portion to effect partial coalescence of the yarns at their points of crossing and to cause the fabric to attain the desired dimensions and then setting the fabric by reducing its temperature below the softening point. The heating of the <PICT:0565180/IV/1> fabric may be prolonged to permit equalization of internal stresses and uniform distribution of heat effects before setting. As shown, the fabric passes from a roll 2 through a tentering frame 3 comprising heating sections 4, 5 and a cooling section 6 to a take-up device 7. The pins or clips 8 carried by chains 9 are moved along guideways 10, 11 having swivel joints 36, 37 by cam discs 12 - 15. The distances between adjacent courses are adjusted by the right- and left-handed screws 28, 29, 30. The supply roll 2 is provided with a drag device comprising clamping blocks 39, 40 and a stationary pin 45 projecting therebetween whereby any desired degree of tension may be placed upon the fabric which is also interlaced between rotatable bars 47, 48 at the ends of the machine to maintain it flat. Heating coils 50 may be provided above and below the fabric during the preheating stage 4. The heating stage 5 may comprise a number of sections provided with coils 52. The fabric is cooled at 6 by cold air through a duct 53. If desired, cold or hot water, steam or other liquids may be sprayed onto the fabric at any stage of the process. A temperature of 150 DEG F. or upward is satisfactory in the preheating stage for fabric comprising yarns of copolymers of vinyl chloride and vinyl acetate.

Inventors

No inventors recorded.

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