| 摘要 |
A triple-threaded chain stitch seam and a method and machine for forming the same for the joining-together of net parts into, for example, a trawler, circular net, etc., in which seam the parts forming the blanket stitch cross one another. The seam is formed by three threads 1, 2, 3, of which the first and the second form rows of loops on opposite sides of the workpiece, whilst the third thread 3 forms so- called blanket loops, which connect two adjacent loops in one row with a loop in the opposite row, the blanket loops being rotated during the loop formation such that their two legs cross between the two rows of loops. The sewing machine for the seam formation comprises a needle 4 and two shuttles 6, 7, which are each provided with a respective loop for the respective thread 1, 2, 3, and movement mechanisms 8, 9, 10 for these. The needle 4 and the first shuttle 6 are led (by 8 and 9 respectively) to and fro in planes lying perpendicular to each other and to the feed direction of the workpiece 5. The second shuttle 7 is swivelled (by 10) transversely and longitudinally, respectively parallel and perpendicular to the feed direction of the workpiece 5. This enables the second shuttle 7 to be led around the edge of the workpiece 5, whereby the parts of the blanket switch can be made to cross. <IMAGE> |
