Patent ID: 8090467

Claim:
An apparatus for knitting fabric using elastic yarns with retractility properties which are fed to knitting needles at least as part of knitting yarns for knitting fabrics under a designated tension T 1 , comprising: a yarn sending device that sends elastic yarns to knitting needles at a designated yarn sending length F; a tension meter that confronts yarn route pathway established between the yarn sending device and the knitting needles, and detects tension T 2 of elastic yarns in a resting phase; means for calculating difference to commute a length L of elastic yarns, present in the yarn route pathway under the tension T 1 designated to the yarns and under the tension T 2 which the tension meter detects, into natural lengths L 1 , L 2 when the tensions T 1 , T 2 are not exerted respectively, and to calculate the difference of natural lengths L 1 −L 2 ; and means for correcting yarn sending length F of the yarn sending device so that the difference between natural lengths L 1 , L 2 calculated by the means for calculating difference decreases.