Patent GB-820812-A (GB)
Title: Method and apparatus for splicing opposite ends of a length of fabric to form an endless belt
IPC: B65H69/04
Filed: 1956-11-23
Abstract: 820,812. Joining ends of paper-makers' felts &c. HUYCK & SONS, F. C. Nov. 23, 1956 [Dec. 2, 1955], No. 35872/56. Class 96. In joining the ends of a length of woven fabric to form a papermakers' felt, the fabric, which may have coloured warp and weft threads spaced at regular intervals, is either woven with a band of parallel warp threads 42, 46, Fig. 7, and no wefts, near each end of the fabric, or is fully woven, and weft threads are removed to form such bands. The end portions of the fabric are then superposed with a spacerbar 38 and a spacer-rod 56 between them, and the two thicknesses of fabric are gripped with the aid of inflatable rubber tubes and part-cylindrical strips or a hollow rod, at 22 and 24. The fabric lies over two bars 34, 52, which have each a row of pins 36, and 54 extending upwardly through both thicknesses of woven fabric so that the unwoven warp threads which extend between may be tensioned by movement of the pin-bar 34, the pin-bar 52 being fixed to the machine frame. A yarn-tying carriage 26, Fig. 4, which is moved intermittently across the machine comprises a housing 178 supported above the unwoven warp threads by arms 180 &c. and rollers 184 and 192 &c. which bear against angle-tracks 186 and 194 &c. The carriage 26 is driven, through an electrically-operated clutch, from a chain 202 passing about a sprocket 206 &c. which is driven by a motor 210 and speed-reduction and change-speed mechanism. The carriage 26 includes also a small motor driving a cam-shaft, a single-revolution clutch ensuring that the cam-shaft completes one revolution for each cycle of operation of the yarn-joining mechanism. The carriage 26 also actuates a yarn-locator 318 with upper and lower projections tapered at their forward extremities to contact the warp threads 42 and 46 and deflect them upwardly, a yarn-selector 330, Fig. 31, being pivoted on an arm 332 which is pivoted on a yarn-selector bar 334, the yarn-selector being brought into contact with the thus-located warps by movement of the carriage 26. Vertical movement of a rod 384 swings the selector-bar 334 about a pivot 370, and rocking movement of a bellcrank cam-lever 376, 374 moves the bar 334 longitudinally so that it rides freely on the upper surface of a roller 385, the bar 384 being constantly urged to the right by a spring (not shown in Fig. 31). The yarn-selector 330 guides each pair of selected yarns 42, 46 into two parallel V-shaped grooves 442, 444, &c., Fig. 48, of a yarn-holder 404, comprising a rectangular frame made of bars 406, 408, pivoted on a shaft supported by two spaced brackets extending downwardly from the carriage 26, the forward end of the bar 408 having an opening 446 formed therein which intersects the grooves 442, 444 and which allows the passage of a vertically-reciprocable needle 448, Fig. 56, also supported from the carriage 26. The needle 448 is spring-urged upwardly, and moved downwardly by a cam at each rotation of the cam-shaft, after the warp ends 42 and 46 have been severed, and have been positioned by the upturned tines 465 of a fork. The needle 448 with a latch or guard 558 held in the open position by a spring blade 564 moves downwardly to penetrate the warp end 42 which closes the latch 558 over the warp end 46 so that the latter is carried through the warp end 42 with the aid of a hook 544 on the needle 448. The latch falls by gravitation so that on retracting the needle the warp end 46 remains in position extending completely through the warp end 42. The joined warps are then drawn into the fabric to an amount depending on its position in relation to the coloured warp threads so that a staggered pattern of splicing is effected. Resinous material sprayed on the joined threads may stiffen them before drawing in. The fringed ends of the fabric are thus brought into abutting relationship and the picked-up lengths of warp are clipped close to the surface. If in the descent of the needle 448 no warp end 46 be engaged on the hook 544, electrical contact will be made between the needle and a blade 568 which will halt the operation and light an indicator lamp.