device in a sewing machine to sew a u00fcberwendlich fadenkette in a seam

摘要

The present invention relates to an apparatus for sewing a thread chain into a seam by an overlock sewing machine, particularly an apparatus for providing a specified length of thread chain remaining in a side of the sewing machine. A cutting device cuts a thread chain formed consecutively with a trailing end of a workpiece at the first operation. In a working face in the vicinity of the cutting device in a fabric feeding side, an air suction nozzle is provided for drawing a separated thread chain remaining in a side of the sewing machine after the first operation of the cutting device. An air injection pipe is provided in a position opposite to an internal bore of a tongue. The air injection pipe blows air toward the internal bore so that the separated thread chain is moved into the internal bore. The separated thread chain is cut by the second operation of the cutting device before or when the separated thread chain drawn into the air suction nozzle is moved into the internal bore by the air from the air injection pipe. IMAGE