GB920552A - Improvements in or relating to sewing machines - Google Patents

Abstract

920,552. Sewing-machines. G. M. PFAFF A.G. Feb. 8, 1961 [Feb. 13, 1960], No. 4651/61. Class 112. A sewing-machine connects two superimposed layers of material by a stitched seam and simultaneously provides, by stitching, a binding or a protective seam for each of the two edges of the material. The needle-bar 3 has a needle holder 11 provided with a needle 12 which co-operates with a shuttle to stitch the layers together, a needle 14 which co-operates with loopers 18 and 22 to form an overedge stitch at the edge of the upper layer and a needle 15 co-operating with loopers 19, 23 to do the same for the edge of the lower layer. As the two fabric layers 61, 62 are fed beneath the needles the edge 63 of the lower layer 61 is pushed down into a recess 45 in the throat plate by an oscillating arm 53 to permit the needle 14 to form an overedge stitch around the edge of the upper layer 62 while the needle 12 is joining the two layers by a seam 65 (see Fig. 2). Simultaneously a further, upper oscillating arm 54 lifts the edge 64 of the upper layer 62 to allow needle 15 to form an overedge stitch around the edge 63 of the lower layer 61. A separating plate 48 is positioned between the fabric layers above the recess 45 in the throat plate and has an aperture for the passage of the needle 14. The arms 53 and 54 are mounted on a member 50 carried on an oscillating lever 52 and are disposed to operate below and above, respectively, the level of the separator 48. Alternatively the member 50 may be mounted on a slide which is reciprocated in a direction perpendicular to the direction of fabric feed. In a modification each of the three needles co-operates with a corresponding shuttle and two edge tapes 71, 72 are folded and fed by known means, to produce the effect shown in Fig. 7. The advanced needle stitches the tape 72 and the upper fabric, the rear needle stitches tape 71 and the lower fabric, while the intermediate needle stitches the seam 65. Stifchforming, governing threads passing to needle eyes.-The unthreaded loopers 22, 23 are adjustably arranged on a support 21 mounted on an oscillating shaft 9. The needle threads 33, 34 pass together through a hole 35 in the shaft 9 and then pass through holes 36, 37 respectively in the arms of a U-shaped guide 32 extending from the shaft 9.