Method and machine for producing a seam which is not susceptible to coming undone

摘要

The invention relates to a method and a machine for producing a seam (12) which is not susceptible to coming undone, with at least one interlooped and/or interlaced stitching thread and with stitching passes in or through at least one thickness of the material of an object, called the sewn object (3). The seam (12) is produced with at least one stitching thread having a thermoplastic material at least on its exterior. At least one infrared laser beam (17, 18) is applied locally to the seam (12) on the exterior of the sewn object (3), which laser beam is adapted to soften punctually the thermoplastic material present on the exterior of at least one strand of thread extending on the exterior of the sewn object (3) and adjacent to at least one other strand of thread. An air jet enables mingling of the softened fibers and at least one pressing device (6) is then applied to the softened and mingled thermoplastic material of at least one strand of thread of so as to join punctually the adjacent strands together.