GB835217A - Method of and apparatus for measuring fibre length distribution in textile slivers, rovings and yarns - Google Patents

Abstract

835,217. Measuring and testine textile slivers &c. WOOL INDUSTRIES RESEARCH ASSOCIATION. March 16,1956 '[March 21, 1955], No. 8098/55. Class 120(3) [Also in Group XXXVI] The distribution of fibre length occurring in a sliver, roving, or yarn is determined by placing successive sections of a tuft with aligned ends, drawn from the sliver &c., between the electrodes of a condenser and measuring the change in the capacity thereof (proportional to the weight of fibres between the electrodes) caused by each section: such measurements provide data from which a "fibre figure" may be constructed. In the operation of the apparatus shown, the tuft F is clamped in a holder 3 of insulating material, supported on a block 6, and inserted between electrodes 1, 1, and the block, slidably guided on a bar 7 is traversed in a series of steps, as indicated by a pointer 4 on a graduated scale 5, by rotation of a screw 8 to place the successive sections between the electrodes: the weight of each section of fibres may be indicated by a scale on a calibrated condenser or recorded directly on paper by a pen which is displaced by the rotation of the scale on such condenser. The condenser 1, 1, may be incorporated in an instrument circuit comprising two high frequency oscillators (with a mixer and an output stage oscillator) the frequencies of which are balanced at each measurement by adjusting a variable condenser to reduce to zero the note produced in headphones connected to the output stage, Fig. 4 (not shown).