Patent GB-344427-A (GB)
Title: Improvements in looms having stationary weft supplies
IPC: D03D47/24
Filed: 1929-12-04
Abstract: 344,427. Looms having stationary weft supply. HARGREAVES, A. DE C., 53, Parque da Liberdade, Fortaleza, Estado do Ceara, Brazil. Dec. 4, 1929, Nos. 37115/29 and 14118/30. [Classes 142 (ii) and 142 (iii).] Weft-replenishing mechanism; bobbinwinding attachments.-I looms having stationary weft supply, the necessity of laying a double pick in the shed is obviated by the provision of a shuttle having a rotary pirn or peg which is automatically rotated, at predetermined intervals and whilst the shuttle is in the box, to take up or wind upon itself sufficient yarn for one, three, or other odd number of picks. When the required length of the yarn has been wound on the pirn, picking begins, but on the first flight of the shuttle the weft for the first pick is drawn from the stationary supply at the side of the loom, the subsequent picks only being laid from the store on the pirn. Thus if a length of yarn sufficient for three picks is stored on the pirn, the cycle of operations is repeated every four picks, the yarn from the main supply attached to the first pick of the group being severed by cutting mechanism and withdrawn by a tension device to a position where it can be caught by the pirn when it is next rotated. In the shuttle d, Figs. 8 and 9, a pirn g, having a brush h to catch the weft protruding from a guide-eye f, Fig. 1, in the shuttle box, is rotatably mounted in a bearing i and provided with a small pinion j to gear with a pinion j<1> on the shuttle which is engaged by the foremost of a train of gears j<2> .. j<7>, Fig. 3, operatively connected to a spring-controlled push-bar m, which is moved backwards by a spring buffer n as the sley advances and is held in this retracted position by a spring and cam-controlled pawl m<2>. A bracket o<1> on the loom sley supports a spindle o provided with cams o<3>, o<4> 05, and a toothed disc o<2>, the latter by its engagement with a spring-controlled member p on the frame causing the spindle o to be rotated. As the spindle is rotated, the cam o<3> engages and withdraws the pawl m<2> and the sudden release of the bar m causes the train of wheels j<1> .. j<7> to be rotated, the number of the consequent rotations of the pirn and the length of yarn wound being determined by: (1) the extent to which the pushbar normally projects forwardly of the sley, (2) the ratios of the gear-wheels, and (3) the position of an adjusting screw which controls the backward movement of the bar. Whilst the bar m is being released, a cam o<4> acts on a spring arm f<1> to press the guideeye f into a slot in the shuttle so that the weft may be caught by the brush h. The rack and pinion means for operating the gear wheels may be replaced by a coiled spring which, after being wound up by means of a pair of pawls and a ratchet disc wheel, is released by timing mechanism shown in Figs. 1 and 3. In modified forms, the pirn is provided with and rotated by a small air turbine or an electric motor, the valves and switches being controlled by the aforesaid cam timing mechanism on the loom sley. A spring-controlled rod r<7>, Fig. 1, having an attached member r<6> is moved by the cam o<5> into the path of a lever on the loom frame to operate the cutting mechanism, which is mounted on a stationary support such as the loom temple bracket. A tension device s<4>, Fig. 3, normally held in the raised position by the pull of the weft, is allowed to drop, along with a pivotally mounted spring- controlled member s, when the weft has been cut, thereby withdrawing the yarn until a small length only protrudes beyond the guide f to be caught by the brush when it is subsequently rotated.