GB301888A - An improved let-off motion of looms for weaving - Google Patents

Abstract

301,888. Franklin Machine Co., (Assignees of Seymour, W. I., and Shanahan, L. J.). Dec. 9, 1927, [Convention date]. Letting-off warps. - Relates to warp beams driven from a. rotating shaft of the loom through ratchet and other gearing, the rate of let-off being controlled by a whip member under the influence of the warp tension, while means is provided for disengaging the pawl from the ratchet wheel. The warp beam 28 is geared to a braked worm shaft 15 having a hand-wheel 16 and a ratchet wheel 21 adapted to be operated by a pawl carrier 17, Fig. 5, loose on the worm shaft and geared to a bevel wheel which is mounted on a shaft 10 having an arm 11 in lost-motion connection with a connecting-rod 3 pivoted to a rotating crank arm 2. The whip member or roll 33 is mounted on one arm of a three-armed lever, one arm 34 carrying a weight 23 while the other arm 35 is connected to a rod 24 pivoted on a shaft 25 which is rockable about the worm shaft and serves as an abutment for limiting the lowermost position of the carrier 17. As the rod 3 moves downwardly, the arm 11 moves to the left by gravity until a notch 17<1> in the pawl carrier engages the shaft 25, the slot in the rod 3 then allows idle motion. On the return motion of the rod 3, the pawls 18 engage the ratchet wheel 21 to drive the beam. When the tension increases, the rod 24 falls and allows further motion of the pawl carrier, so that the let-off is increased. In order to put the let-off mechanism out of action for hand adjustment of the beam, a curved member 39 straddling the worm shaft is adapted to be raised by link and lever devices from a hand lever 45 to engage projections on the pawls, whereby they are raised from engagement with the ratchet wheel.