GB1172022A - Weft Straightening Apparatus - Google Patents

Abstract

1,172,022. Feeding webs. COLTRON INDUSTRIES Inc. 9 May, 1967 [9 May, 1966], No. 21574/67. Heading B8R. [Also in Division D1] In apparatus for correcting, by means of suitably manipulated rollers, bowing or skewing of weft yarns relative to the warp yarns of textile fabrics caused during processing, web-feeding rollers having identical linear surface speeds are provided to feed the fabric to and to advance the fabric from the correction apparatus, so that the fabric passes through the apparatus with substantially uniform tension. As shown in Fig. 1, the fabric web F passes around a feed roller 11, pivoted rollers 20, 21 for correcting skew, curved-axis rollers 18, 19 for correcting bowing, an intermediate feed roller 14, past scanning discs 23, 24, and around feed rollers 15, 16. According to U.S.A. Specifications 3,192,595 and 3,193,688 referred to, the skew rolls 20, 21 have pivotal movement about an axis central to their length and perpendicular to the roller axes, the pivotal movement being controlled by the scanning devices. The bow rollers 18, 19 are rotatable about curved shafts which can be adjusted under control of the scanning devices 23, 24. The feed rollers 11, 15, 16 are driven at the same surface speed from a motor 25 through a belt 40, gears 41, 42, and belt 30. As shown, a gear 45 on the shaft 36 of roller 11 drives, through transmission means 44, sprockets on the shafts of the rollers 14, 18, 19, 20, 21 so that all these rollers rotate with a surface speed equal to that of the rollers 11, 15, 16. The drive (Fig. 4) to the bow rollers 18, 19 is such as to permit of the adjustment movements of their shafts. According to a modification, (Fig. 3, not shown), the drive to the rollers 14, 18, 19, 20, 21 is omitted and the roller 11 is replaced by two driven rollers around which the fabric passes before reaching the correction rollers. The scanning discs 23, 24 are driven in one or other direction of rotation according to the particular fabric being treated, the drive 75 being from the shafts of the rollers 15, 16 and including clutch devices which can be set to cause the required direction of rotation. According to the U.S. Specifications mentioned, beams of light pass through slots in the discs and in fixed tables supporting the fabric sides and impinge on photo-electric cells to determine the frequency with which the threads pass the scanning devices. This is employed to determine weft misalignment and to operate through electrical circuitry, motors which pivot the rollers 18 . . . 21 to effect the required correction.