Patent GB-245791-A (GB)
Title: Improvements in or relating to looms for weaving pile fabrics
IPC: D03D39/02
Filed: 1926-01-08
Abstract: 245,791. Friedrich, G., and Reich, E. Jan. 9, 1925, [Convention date]. Pile-fabric looms. - in looms for weaving pile fabrics in which the pile knots are formed around the warps, simultaneously operated jacquard-controlled knotting-devices 14, Figs 1 and 2, each commanding a section of the warp threads, are mounted singly or in groups in rockable frames, and the operating parts of each knotting-device are driven by a common driving-shaft 38 extending across the loom. The frames or holders of the knotting-devices, described below. are pivoted about the shaft 38 and are moved by lead shafts 37, 52, Fig. 1, either continuously or step by step after each knotting-device has operated. When pile loops have been supplied to the whole width of the warp sections, the knotting-devices are raised to an inoperative position by levers 39 on a common shaft. The pile loops are then beaten up, and after one or more shots of weft have been inserted, afresh row of pile loops is formed, the knotting-devices traversing the warp sections in the same or in the reverse direction. Selvage-forming devices 14<a>, also described below, are mounted and driven in a manner similar to that of the knotting-devices. The selvage. forming and knotting-devices can be arranged at any position on the shaft 38 to adapt the loom to any width of fabric. Instead of moving the knotting-devices across the loom, they may be stationary, the weaving mechanism being moved. The machine is described below as applied to the production of Smyrna knots, but it can be adapted to the formation of Persian knots bv suitable alteration in the control of the warps. The warps of each pair about which a knot is to be formed are raised in succession to be held by the warp-end guide or positioner. This may be effected by the employment of two dobbies 12 acting in succession on the even and odd warps, or by forming the comber board 9 in two parts for the even and odd numbered warps, so that the two warps of a pair are raised unequally for reception by the warp position which guides the pair of warps to lie above but parallel to the remaining warps. In some cases, the knotting-devices operate to produce knots which are initially in a plane parallel to that of the fabric, each warp positioner then causing the pair of raised warps to lie in a plane at right-angles to the fabric, and the pile threads being laid against the raised warps. Each knotting-device comprises a jacquard-controlled colour selector; a pair of tongs for gripping the selected thread and drawing out sufficient to form the pile loop: a loop former: a knife; a warp-end guide for positioning the raised warps about which the loop is to be formed: and a loop tightener. Colour selector. The colour selector comprises a freely-mounted cylindrical part 78. Fig. 3, having peripheral slots in which are arranged hollow pile feeders 91. The pile thread 15 passes through a hole in the cover of the cvlinder through the pile feeder to a thread clamp 98 controlled by a spiral or flat spring, the free end of the thread being directed inwardly at 15<a>. The feeders are held in the inoperative position shown by a ring 80 engaging parts 91<a> of the feeders. The cylinder 78 is turned to bring the selected feeder over a slot 81<a> in a fixed base, and a slide 95 normally completing a gap in the ring 80 is lowered to bring the end 15<a> into position to be engaged by the tongs, a projection 100 engaging an abutment to release the pile thread. To rotate the cylinder to bring the required feeder 91 into position to be lowered, a jacquard-operated abutment 92 is arranged in the cylinder behind each feeder. When a jacquard cord 16 is raised, the corresponding abutment 92 is moved into position to be engaged by oppositely-rotated pushers 88, 89. which are moved from the position shown in Fig. 4 to that shown in Fig. 5. The cylinder 78 is provided with a fixed abutment 90 so that, when the pushers return to the position shown in Fig. 4, the cylinder is returned to an invariable inoperative position. In a modification, the carrier for the pile thread feeders has a longitudinal instead of a rotary motion. The abutment 90 may be omitted, in which case only half the perimeter of the cylinder 78 is supplied with thread feeders. In the form in which the pairs of warps are arranged in planes at right-angles to the fabric for the knotting-operation, the pile-thread feeder 120, Fig. 38. is provided with three pairs of grippers 121, 122, 128 which hold the pile thread 15 against the warps 7. At the completion of the knotting, operation, the tongs hold the pile-thread below the grippers 121 so that, when the feeder rises, sufficient thread is drawn out to produce a subsequent knot. Tongs. The thread 15 extending from the lowered pile feeder 91, Fig. 50, is seized by a pair of tongs 165 which move from the position shown in full lines in Fig. 51 to that shown in dot and dash lines. In the form in which the pairs of warps are arranged in planes at rightangles to the fabric for the knotting operation, the tongs for seizing the pile in the pile feeder 120, Fig. 38, below the grippers 121, comprise interfitting jaws mounted on arms adapted to be swung to and from the feeder 120 while the jaws are open or closed as required. Loop former. The selected pile thread 15, Figs. 9 and 10, is positioned above the raised and positioned warps 7 and its ends are seized by two pairs of grippers each composed of relativelymovable parts 59, 60 having extending parts forming clamps 61, 62. The grippers descend, are moved towards each other, and then rise between the warps 7. a pusher 58 arranged between the warps preventing the clamps from engaging the pile thread between its ends. Modifications of the jaws of the loop former are shown in Figs. 21--24. In another form, the jaws are rotatably mounted and form the twisting operation by simple rotation. In a modification, rotatablymounted jaws 59, 60, Fig. 25, produce the knot by rotating in one direction to bring the pile ends beneath the warp threads 7 and then rotating in the other direction to bring the ends up between the warps. In another form, the jaws of the loop former are mounted on flexible parts 59, 60. Fig. 18, movable in guides 76, 77 and form the knot by the simple depression of the parts 59, 60. In a modification, the jaws mounted on springs 77, Fig. 28, movable in guides 76 produce the knot by a compound motion similar to that employed in the form shown in Fig. 9. In the form in which the pairs of warps are arranged in planes at right-angles to the fabric for the knotting-operation, the severed vertical pile thread 15, Fig. 46, lying against the raised warps 7 is bent into the shape shown by the entrance of a projection on the carrier for the knotting-tools entering a recess in the pile thread feeder 120. The loop formers. 141 - - 144 then seize the ends of the pile thread and the clamps 122, 128 are opened completely. The formers then move in the direction of the warps, converge, and carry the pile ends between the warps. They then move in a reverse direction along the and hand the knot to the knot tightener which the loop and, in some cases, assists other parts to turn it from the horizontal position into a vertical position. Pile-thread cutter. The pile thread is severed by a rotating disc 162, Figs. 50 and 51, mounted on an arm adapted to swing the disc into position to sever the selected thread. In the form in which the pairs of warps are arranged in planes at right-angles to the fabric for the knotting- operation, the pile threads are severed by camoperated knives co-operating with fixed blades. Warp positioner. Each pair of raised warps about which the pile is to be knotted is engaged by a fork 190. Fig. 58, having three prongs and mounted on the knotting-device. The fork is capable of vertical and lateral movements. In operation, the fork is positioned so that the lefthand thread comes opposite the space 198 between two prongs. The prongs then descend and move to the left, the right-hand warp thread then being held in the space 199 between the prongs of the fork. The fork then moves to its central position and holds the separated warp threads for the pile-forming operations. When the pairs of warps are arranged in planes at right-angles to the fabric during the knotting-operation, that is effected by notched discs 110, Figs. 34 and 38, mounted on a bar 110<a>. In operation, one warp thread 7 is raised and is engaged by the prongs 113 of the discs which are rotated about pivots 111. The second warp thread 7 is then raised and enters the notch 115. Upon further rotation of the discs, the warp threads occupy the positions shown in Fig. 38, a space being left between the bar 110<a> and the warps fnr the insertion of the pile feeder 120. In a modification, the first warp thread 7, Fig. 36, is raised and is received in a notch 119 in a pronged lever 117. The lever then moves to the position shown in full lines and the second warp thread is raised till it engages the lower side of the prong, the warps thus being arranged in a plane at right-angles to the fabric. Loop tightener. The upstanding ends of the pile loop iormed by the device shown in Figs. 9 and 10 are seized by jaws 166. 167. Fig. 51, which move the pile loop towards the fell of the fabric, and after drawing the knot tight, release it. In the form in which the pairs of warp threads are arranged in planes at right-angles to the fabric during the knotting-operation, the loop tightener comprises a pair of cam-controlled jaws adapted to turn on pivots so that the seized loop is turned from the horizontal position in which it is made into the final vertical in the fabric. Selvages, forming. - The selvage-forming devices 14<a>. Figs. 1 and 2, are mounted on and operated by the shaft 38 in the same manner as the knotting devices. The flat ends 214a, Fig. 54, of the spindle of the selvage shuttl