| 摘要 |
PCT No. PCT/EP89/00616 Sec. 371 Date Feb. 6, 1991 Sec. 102(e) Date Feb. 6, 1991 PCT Filed Jun. 1, 1989 PCT Pub. No. WO90/00640 PCT Pub. Date Jan. 25, 1990.An overcast sewing machine in which a plurality of different stitch types can be sewn. Various designs are disclosed for sewing alternatingly the stitch types 512 and 514, which consist of two needle threads, one lower looper thread and one overcast looper thread. In one design, the holder of the overcast looper can be fixed in a first working position, in which both needle threads are interlinked with the overcast looper thread, and can be displaced into a second working position, in which only one needle thread is interlinked with the overcast looper thread. According to another design, two thread eyes are provided in the overcast looper and the overcast looper thread is threaded through one of these thread eyes to form one of the stitch types and through the other thread eye to form the other stitch type. In addition, stitch type 504, consisting of three threads, can be formed by removing one needle. To form a stitch type 502 consisting of one needle thread and one lower looper thread, an overcast looper with a fork-shaped catching tip can be moved on the looper holder from a resting position into a working position, in which the lower looper thread is laid around the edge of the material being sewn and is fed to the needle for penetration. The stitch-forming devices mentioned above are associated with additional stitchforming devices for forming a double chain stitch seam stitch type 401, DIN 61400, U.S. Federal Standard Catalogue Number 751.
|
