Method and apparatus new to determine the average length of the cotton fibers or the like, as well as the average weight per unit length of fiber similar

摘要

420,960. Measuring the mean length and/or mean weight per unit length of cotton or like fibres. INDIAN CENTRAL COTTON COMMITTEE, Vulcan House, Nicol Road, Ballard Estate, Fort, Bombay, India. May 14, 1934, No. 14513. Convention date, May 19, 1933. [Class 120 (iii)] The mean fibre length of raw cotton or other textile fibres is obtained by taking a representative sample of the fibres, combing it out, selecting therefrom a bunch of fibres with aligned ends, cutting off a measured length from the aligned end and from the centre by dividing the bunch at two points and thereby forming three groups, calculating the average length of the uneven ends in the third group by comparing its weight with the weight and known length of the fibres in the first group and adding the calculated length to the known length of the first and middle groups to give the mean length of the fibres in the bunch. A sliver of the cotton under test is engaged in the combs 1 and a number of groups of fibres are nipped by the jaws 5 of tweezers 3 having springs 3a and supported on a slide bed 4 and are thereby withdrawn from the sliver and discarded until all the projecting ends are in alignment. A test sample bunch is then detached and stray fibres removed by combing. The screw 7 is then released and the tweezers rotated through 180‹. The projecting ends are now gripped by the tweezers 14 on the carriage 8 and the latter moved back until the fibres are straightened over the bridge piece 9. The cutter 12 comprising blades 11, 18 separated by a distance piece 19 is then lowered by the handle 17 to cut the bunch of fibres into three portions. The length of the first portion is read on a vernier scale while the width of the plate 19 is known. The three portions are then weighed and the average length of the fibres in the third group calculated by comparison with the readings of the first group, thus avoiding any inaccuracies due to the fibres being thicker at about the middle of their lengths. If desired the mean fibre weight per unit length may be found by dividing the total weight by the number of fibres and the ascertained mean length.