GB422015A - Improvements in and relating to the drawing of bast and long leaf fibres - Google Patents

Abstract

422,015. Drawing-apparatus for bast and long leaf fibres. STONE, M. B., Canton Avenue, Milton, and WILLIAMSON, W. P., Ludlow, both in Massachusetts, U.S.A. Dec. 8, 1933, No. 34663. [Classes 120 (i) and 120 (ii)] A drawing-head for drawing fibres of flax, hemp, jute, ramie, sisal, and manilla comprises pairs of feed and drawing rollers and at least two slip draft devices one of which consists of a pair of rotary elements and another of which situated nearer the feed rollers is connected to one of the said rotary elements so that the pressure of the sliver on it causes the rotary element to be urged towards its fellow. In the drawing- head of a spinning frame three slip-draft devices comprising a rod 6, a channel 7, having a bell-mouthed entrance and slightly curved base, and fluted rollers 8, 8<a>, Figs. 1 and 2, are arranged between the feed rollers 2 and drawing rollers 3. The roller 8 is positively driven and drives the roller 8<a> which is formed of reduced diameter over its central portion and is mounted on an arm 9 pivoted at 10. The rod 6 is disposed adjustably in a slot 12 in an arm or bracket 13 while the channel 7 is mounted by a bracket 14 slotted at 15 on the arm 9 which supports the roller 8<a> so that on the passage of a bunch of long fibres the greater pressure on the channel 7 is transmitted through the arm 9 to the rollers 8, 8<a> thus increasing their retarding action and preventing the passage forward of short fibres. In a drawing-frame four slip-draft devices are interposed between the feed rollers 21, 22 and drawing rollers 23, Fig. 4, and comprise a stationary rod 35, a channel 36 and two pairs of positively driven rollers 37, 37<a> and 38, 38<a>. The channel 36, Fig. 6, comprises a curved base 41 and substantially helical side walls 42 the rod 43 being angularly adjustable to provide passages of varying width. The channel 36 is mounted on the bracket 39 supporting the rollers 37<a> 38<a>. The roller 38<a> is mounted in a loose bearing and bears on the roller 38 by its own weight only. The roller 37<a> is fixed relatively to the bracket 39 and is loaded thereby and by the action of the channel 36. In a modification, the four devices comprise a rod 50, two channels 51, 52 and a pair of rollers 53, 53<a>, Fig. 7. The channels are of V-cross-section Fig. 8, and are mounted respectively on an arm 54 adjustably pivoted on the bracket 55, which carries the roller 53<a> and on an arm 56 which carries the roller 53. If desired the V-groove, Fig. 8, may be widened considerably while the form shown at 57, Fig. 9, may alternatively be adopted. The open sides of the channel members may also be closed by a weighted or spring pressed member. Specification 407,690 is referred to.