Weft Selection Device for the Selective Feeding of Weft Yarn from at least Two Weft Yarn Supply Bobbins to a weft Yarn Inserter in a Shuttleless Weaving Loom

摘要

1,151,337. Shuttleless looms; weft patterning devices. DRAPER CORP. 27 May, 1966 [1 June, 1965], No. 24050/66. Heading D1E. A loom of the kind wherein a loop of weft is taken into the shed by an inserter, transferred to a receiver and then straightened out has a weft selection mechanism which selects a weft and presents it to the inserter so that it is inserted in the form of a "hairpin", he legs of which are in different sheds. There may be a selection mechanism at each side of the loom. A cam shaft 33 (Figs. 1 and 2) drives a pattern chain 61 which moves a rack 68 into one of four different positions and the rack 68 oscillates a segment gear 79 to turn a selector shaft 80 to one of four stations corresponding to the number of wefts. The selector shaft 80 is locked in position by a cam operated plunger 180. The selector shaft 80 carries a weft braking device 82 (Fig. 4) and a cutting and clamping device 83. Between the devices 82 and 83 is a weft presenter 162, operated from the cam shaft 33, that depresses a selected weft into the path of the inserter 111. The braking device 82 (Figs. 4 and 6A) comprises a plate 84 with guides 87 for each weft and four separate braking and guiding units, one for each weft. Each unit comprises leaf spring braking plates 88, 89 acted on by a plunger 96 that is spring loaded and is axially movable by a rod 164, operated from the cam shaft 33, to clamp the weft and a spring loaded guide 102 that is longitudinally movable by a puller 177, operated from the cam shaft 33, to place the weft in the paths of the presenter 162. The cutting and clamping device 83 (Figs. 4, 8A and 17) comprises a spring loaded longitudinally movable shaft 135 which has clamped to it a guide 133 which is prevented from rotating and can only move longitudinally when acted on by a pusher 172 operated from the cam shaft 33. The guide 133 carries a member 127 having a weft guide slot 129, an edge 128 that cooperates with a fixed member 120 to cut the weft, a face 126 that cooperates with spring loaded plates 122, 123 to clamp the cut weft and a guide 151 which has a nose 134 which cooperates with a spring loaded lever 154 to clamp the weft when the guide 133 is moved longitudinally. In use, with all four wefts clamped by the members 127 and 122, the pattern chain acts to rotate the shaft 80 and thus the units 82, 83. The puller 177 moves to bring the guide 102 and the selected weft F under thep resenter 162. The presenter 162 moves downwardly to bring the weft into the path of the inserter 111 which, as it enters the shed and with the weft still held in the clamps 127, 122, pulls out a loop of weft through the guides 87, braking plates 88, 89 and through the guide 151. At centre of the shed the inserter 111 transfers the weft to a receiver (not shown) and, simultaneously, the rod 164 is operated to clamp the weft between the plates 88, 89 and the pusher 172 is operated to open the clamps 127, 122 so that the weft is clamped by the nose 134 and lever 154 and its end is released so that it may be straightened out by the receiver as it retracts from the inserter 111. The weft then extends from the supply through the units 82 and 83 to the far side of the shed and it is beaten-up to form the first leg of the hairpin. The presenter 162 then again operates to present the weft to the inserter 111 the brakes 88, 89 are released and the weft is taken to the centre of the shed. The guide 133 is then released by the pusher 172 so that it cuts the weft which is pulled into the shed and straightened out to form the second leg of the hairpin and at the same time clamps the weft extending from the supply in preparation for the next selection and insertion.