Patent GB-1028303-A (GB)
Title: Splicing of yarns
IPC: D05B37/04
Filed: 1962-12-20
Abstract: 1,028,303. Sewing machines; yarn winding apparatus. DEERING MILLIKEN RESEARCH CORPORATION. Dec. 20, 1962 [Dec. 21, 1961], No. 48163/62. Headings D1G and D1V. Means for stitching together two yarn ends comprise a two-thread zig zag sewing machine, clamping means for holding one yarn end trained past the stitching point with the free end extending opposite to the sewing feed direction and the yarn under a take-up bias in the feed direction, a first cutting means for severing said free end at a predetermined distance from the stitching point, means for positioning the other yarn end adjacent the first yarn end with its free end extending in the feed direction, second cutting means for severing the free end of said other yarn and the starting lengths of the sewing threads adjacent the start of the stitching as it feeds out of the sewing mechanism, and a third cutting means for severing the sewing threads adjacent the end of the stitching as the joined yarns are removed from the sewing mechanism, the thread ends being held upon severing at the third cutting means. A zig zag sewing machine 100, adapted to join two yarn ends together, is provided with a fixed plate 124 which overlies the normal work-supporting surface and which is formed in its front edge with a deep notch. Secured to the base of the latter is a forwardly-projecting plate 122, to the front edge of which is secured a presser foot 116 provided with a boss 120 against which the lower end of the presser bar bears. The front edge of the presser foot is formed with an upturned lip 132, the side edges 134, 136 of which slope inwardly to join the body of the presser foot at the respective sides of a rib 140, Fig. 7 not shown, formed on the under surface of the presser foot. Lip 132 is also formed with a thread-passing slot 138 which enters the elongated needle-passing slot 118. Rib 140 is formed at the base of lip 132 with a transverse, yarn-positioning groove 126, Fig. 7, which intersects the needle slot 118 and which has a vertical rear surface 128 and a forwardly-sloping surface 130. The front corners of the presser foot are bevelled as at 142<SP>1</SP>, 144<SP>1</SP>. A first yarn-champing device comprises a plate 146 mounted on plate 122 and the presser foot with its front edge aligned with the right hand edge of the latter, the pressure which plate 146 ealats downwards being regulated by a wing nut 154. A second yarn-clamping device comprises a blade 174 pivoted at 176 to plate 124, a blade 184 biased downwards against blade 174 by a leaf spring 188, and a spiral spring 178 which is connected at its respective ends to plate 122 and blade 174, and which is adapted to bias the yarnclamping end of the latter away from the needle slot 118. A first yarn-severing device comprises a stem 160 adjustably secured to plate 124, an upwardly-tilted plate 158 rigid with stem 160, positioned behind the front edge of plate 146 and formed in its rear edge with a notch 162, and a knife blade 164 secured to plate 158 at the base of notch 162. A second yarn-severing device comprises an upturned plate 166 mounted on plate 124 and having a front edge which is positioned behind the left hand front edge of the presser foot and is formed with a notch 170, and a knifeblade 172 secured to plate 166 at the base of notch 170. A thread-severing-and-clamping device 190 at the left hand front edge of plate 124 is formed with a notch 194 at the base of which is mounted a knife blade 196 and under which is disposed a pair of jaws 197, 198 pressed together by a spring 198<SP>1</SP>. In operation, a yarn a is secured at a distance from its free end between the clamp blades 174, 184, blade 174 is moved adjacent plate 166, and the yarn extending therefrom is passed under plate 166 and through groove 126 in the direction opposite to that of the work feed and in contact with surface 128, under plates 146 and 158, and is finally drawn down notch 162 to be severed at blade 164 at a predetermined distance from needle slot 118 in accordance with the length of join required. The end of the second yarn b is passed under lip 132 and into groove 126 in the direction of work feed, the yarn being guided by surface 130 into abutment with yarn a. The free end of yarn b and the needle and bobbin threads x and y are then held in the operator's left hand, and the machine is started to stitch together the yarns a and b in the groove 126. When the leading end of the stitching reaches the notch 170, the free end of yarn b and the threads x and y are drawn therein to be severed by blade 172 at said leading end. On completion of the stitching, the threads x, y are drawn into the clamp jaws 197, 198 and are severed by the blade 196. The sewing machine is incorporated in apparatus adapted to join together the ends of yarn projecting from respective ends of spools, and to wind the yarn from one spool of each pair on to the other spool, the apparatus being used to recover the residual yarn from spools used in the manufacture of nylon tyre cord. A circular table 13 is journalled on a vertical spindle 15 and carries eight pairs of rotatable spool-receiving spindles 11, 12 situated on two concentric rings, the spindle 12 being on the smaller circle and being formed with grooved portions 19 under the table 13. An endless bell<SP>1</SP> 20, driven by a motor 26, engages the portions 19 of five successive spindles 12 in the spool-winding range, the arrangement being suchthat said spindles are rotated to wind yarn on the associated spools T from the respective supply spools S on the adjacent spindles 11, while table 13 is given an angular bias in the counter-clockwise direction. Belt 20 also passes over idler pulleys 21, 22, 23 so arranged that the portions 19 in successive spindle-braking and yarn-joining positions do not contact the belt, while the latter makes only tangential contact with portion 19 in the succeeding slack take-up position. The lower flange of the supply spool in the spindle-braking position engages a brake shoe 52. Mounted under table 13 inwardly of each spindle 12 is a roller 28 so arranged that the roller associated with the spindle 12 in the spindle-braking position abuts an escapement 27 to hold table 13 stationary. A handle may be manipulated to disengage the escapement from said roller 28, when the escapement 27 engages the next oncoming roller 28. The supply spool in the spindle-braking position is normally empty, and is replaced by a fresh supply spool, the yarn a from which is joined to the yarn b from the associated take-up spool by the sewing machine 100 in the succeeding yarn-joining position to form a slack loop c. The latter is prevented from becoming entangled with the apparatus by being looped over the uppermost one of a series of hooks 59 carried by an endless chain 56 engaged with upper and lower idler sprockets 57 and 58 respectively. The lower flange of the supply spool in the slack take-up position engages a brake shoe 60, and the associated take-up spool is rotated by the belt 20 until the loop c is tightened, when belt slipping occurs owing to the tangential contact of the belt thereat.