GB653735A - Improvements in and relating to drawing heads for long staple fibres - Google Patents

Abstract

653,735. Textile drawing apparatus. MACKIE & SONS, Ltd., J., and MACKIE, J.P. June 9, 1947, Nos. 16147/47 and 1044/48. [Class 120(ii)] A drawing head for jute or similar long staple fibres in which a sliver is acted upon by slip draft devices over a length equal to at least one quarter of the length of the sliver path has the sliver path arranged to be considerably longer than the distance between the retaining and drawing rollers. In one embodiment, Fig. 1, a sliver S is drawn between retaining rollers 12, 13 and drawing rollers 14, 15 and slip draft control is effected by a roller 21, positively driven at a speed slightly greater than that of the retaining rollers 12, 13, and a pressing roller 22 lightly urged towards the roller 21 by an adjustable spring 23. The sliver is pressed against the rollers 21, 22 over more than a half of its path. In another modification, wherein the retaining rollers are located behind the drawing rollers with the nips almost horizontal the sliver is passed over a large slip draft roller which may be roughened, or covered with a material to which fibres may cling, such as rubber, cork composition or leather. Alternatively, the slip draft roller may be provided with a rubber or other belt, such as 32, in Fig. 2A, which passes round a roller 30 and a tension pulley 33. In another form, a belt similar to belt 32,. may be passed over a fixed curved plate, preferably flanged. Drive to the belt may be from a driven fluted roller. A stationary flanged curved plate without a belt may be employed. In a further modification, a belt may be supported by two positively driven and two idler rollers, a presser roller being lightly urged against the belt as it passes round one of the positively driven rollers. In other modifications, the sliver is caused to make a large arc of contact with the driven retaining roller which may be flanged and fluted. The..driven slip-draft roller may also be flanged and fluted. Also, a sliver may be passed completely round the slip draft roller-and a presser roller may be urged against the sliver as it leaves this slip draft roller. According to the first Provisional Specification, the presser roller may press against two strands of the sliver on the slip draft roller. This Specification also envisages slip draft control imposed by two belts between which a sliver is gripped. According to the second Provisional Specification a large slip draft roller may be formed circumferentially with a curved channel, or a straight-sided furrow, or alternatively transverse corrugations may be formed by bars fitted across slots in the roller. Specifications 407,671, 407,690, 407,707, 509,493 and 516,466 are referred to.