| 摘要 |
<PICT:0710708/IV (a)/1> The permanent elongation of a finished thread, yarn or cord of regenerated cellulose or cellulose derivative is reduced, and the strength and resistance to fatigue after continued dynamic stress are improved, by subjecting it while it is travelling in continuous manner to a rhythmically alternating tensile stress of between 10 and 50 per cent. of its ultimate tensile strength so as to apply at least 100 alternations of load to each elementary length of the thread, yarn or cord. The treated material is particularly suitable for tyre cord. As shown, thread, yarn or cord, or cord fabric, is taken from a spool or ball 1 and passed round driven rolls 2, 3, 4. The speed of these rolls may be varied by means of a regulable drive. The travelling material is stretched by the assembly of rolls 5, 6, 7, which have a greater peripheral speed than the first set of rolls. Winding takes place on a beam or spool 8 which is provided with a friction drive. Pulsating movement is imparted by a reciprocating loading roll 9. The frequency of pulsation may be 500 strokes of the loading roll per minute.
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