Textile drafting mechanism

672,728. Drafting textile fibres. SACOLOWELL SHOPS. Aug. 9, 1949 [Aub. 18, 1948], No. 20746/49. Class 120(ii) A fibre control mechanism provided between two pairs of drafting rollers comprises a sliver-supporting apron, lower apron-driving roll and an upper roll in contact with the apron, either the driving roll or the upper roll having outer peripheral end portions and a central portion of lesser diameter provided with a smooth surface for imposing a light frictional grip on the fibres. A drafting apron 8 passing over driving roller 3 and a bar 9 is tensioned by a roll 10. A roll 6 rests upon the apron to control fibres extending between drafting rolls 2, 5, 4, 7. In order to tension the sliver, but without imposing a draft between the rolls 3, 6 and 4, 7, the rolls 3, 6 are driven at a slightly higher speed than the rolls 4, 7. Adjustment of the position of the rolls 4, 7 is possible by moving a bearing block 15, but the apron roll 3 and bar 9 are fixed. Slight movement of the pressure roll 6 to accommodate irregularities in the sliver are permitted by providing the roll 6 with rotary collars B, Fig. 3, which rest on stationary steps or shelves (not shown) on the bar 9. A spring hook 33 pivoted on a bracket 34 secured to the bar 9 provides weighting for the roll 6, which is pressed firmly against the apron 8 as it passes over the roll 3. Grooves are provided in the roll 3 at C, so that the apron 8 may be yieldingly depressed by the sliver and the roll 6 has a resilient cover or cushion R, which leaves a clearance betwen its fibre contacting surface and the apron 8. A minimum clearance of about 1/16 inch is maintained between the ends of the roll 6 and the top of the bar 9. The pressure rolls 5, 7 are weighted by a spring and lever system comprising a spring 32, a channel-shaped lever 27 and links 25, 24, 23, 22. Specification 524,666 and U.S.A. Specification 2,329,655 are referred to.