Patent RU-2290464-C1 (RU)
Inventor: BUSYGIN EVGENIJ VASIL EVICH
IPC: D05B1/22
Filed: 2005-07-13
Granted: 2006-12-27
Abstract: FIELD: clothing industry; methods and equipment for production of the edge-overlock two-thread buttonhole stitch. 
     SUBSTANCE: the invention is pertaining to the field of textile industry, in particular, to the method of production of the edge- two-thread buttonhole stitch and to the edge-overlock two-thread buttonhole stitch sewing machine for the method realization. The invention is dealt with the field of sewing and may be used at production of garments. The overlock two-thread buttonhole stitch is gained by the material edges-basting from below by the needle thread and from above by the looper thread with formation of the line of the stitches sequentially arranged along the edge of the material. For this purpose the needle thread by means of the needle arranged at an angle to the direction of the material movement is pulled through the material and from below in the formed overlock loop of the needle thread by the move from behind the needle introduce into it the thread of the looper moving in the plane perpendicular to the edge of the material. For this purpose the looper is moving behind the needle and from below using the U-turn introduces the needle thread into the loop-overlock, hooks it and stringing it onto the looper pull the thread beyond the edge of the material. After the needle coming from the material the thread of the looper is transferred by the looper from below upward under the needle simultaneously moving the material by the value of the stitch. Then through the formed loop-overlock of the thread of the looper and through the material using the needle pull the needle thread, hook by it the loop-overlock of the thread of the looper and then the thread of the looper is drawn beyond the edge of the material, drop from the thread looper the earlier hooked loop of the needle thread exercise the stitch tightening. After that the looper with the thread again introduce into the formed loop-overlock of the needle thread from below the material. The sewing machine for fulfillment of the edge-overlock buttonhole stitch contains the gear for relocation of the needle, which connecting-rod is connected to the arm of the rocker, the other arm of which is hinged to the link of the drive of the needle carrier. The needle carrier is mounted at an angle to the direction of the material movement. One end of the shaft pf the rocker is fixed in the body, and the other - in the rotating bush made jointly with the eccentric of the manual rise of the presser for the hold-down of the material. The knife gear contains the connecting-rod and the roller, on the end of which there is the fixed lever with the knife. The gear of the looper contains the lever connected by the ball hinge with the connecting-rod and the rocker, on one end of which there is the fixed looper, and its other end is pivotally coupled to the lever arranged on the shaft of the crank. The gear of relocation of the material additionally contains the spring for provision of the kinematic link of the bed with the eccentric of the toothed bar rise. 
     EFFECT: the invention ensures the improved method and the increased efficiency of operation of the sewing machine for fulfillment of the edge-overlock buttonhole stitch. 
     2 cl, 8 dwg