GB1127912A - Improvements in or relating to the winding of synthetic textile yarns or filaments - Google Patents

Abstract

1,127,912. Ripg-spinning apparatus. IMPERIAL CHEMICAL INDUSTRIES Ltd. 22 April, 1966 [10 May, 1965]. No. 19629/65. Headings D1D and D1F. A method of winding yarn on to a bobbin by a ring and traveller, comprises rotating the bobbin at a speed lower than that of normal winding while the yarn is wound on to a wastereceiving end portion of the bobbin, applying a tension to the yarn during the low speed rotation of the bobbin by means of increased drag between the traveller and the ring brought about by magnetisation of the ring or the traveller or both, and thereafter increasing the speed of rotation of the bobbin to normal winding speed and winding the yarn on to the body portion of the bobbin. Either the ring or the traveller may be magnetised or an attractive force between the ring and the traveller may be obtained by the use of a permanent magnet, e.g. an annular magnet disposed near or in the ring. The process is useful in the winding of synthetic filaments or yarns which are heated during stretching, e.g. by a heated snubbing pin disposed between a pair of feed rolls on the one hand and draw and separator rolls on the other, the peripheral speed of the draw roll being higher than that of the feed rolls. For convenience, threading-up takes place before the pin is heated; if on the one hand the yarn is allowed to remain in contact with the pin, breaks occur as the pin is heated up; on the other hand, if the yarn is .taken up at normal speed, undue waste of yarn results. Consequently the wastage is minimized by rotating the take-up at low speed, by an auxiliary motor through an over-running clutch which permits the motor to free-wheel during highspeed winding. At low take-up speeds, however, the yarn between the draw rolls and the traveller is normally virtually without tension, and by imposing a magnetic drag on the traveller .the regularity of the take-up of the yarn is improved.