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US 4,658,752 AGranted
Method and apparatus for drawing a needle thread through a workpiece
AssigneeKochs Adler AG
InventorsWerner Keilmann, Hans Scholl, Gunter Raupach
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AssigneeKochs Adler AG
InventorsWerner Keilmann, Hans Scholl, Gunter Raupach
Estimating the term…
A method for drawing the free end of the needle thread from the upper workpiece surface to the lower workpiece surface when sewing the first stitch of a seam to be produced by a sewing machine having a reciprocable needle, which carries the needle thread drawn from a spool by means of a thread lever, at least one presser foot lowerable upon and liftable from the workpiece, and a rotatingly drivable hook, the point of which seizes and withdraws the needle thread for the stitch formation. In order to safely and automatically prevent the thread end of the needle thread from being clamped between the presser foot and the workpiece, the needle thread is held between the needle and the thread take-up lever while the needle thread loop is withdrawn by the hook beak, so that the thread end is drawn through the workpiece by the hook beak.
Method for drawing a free end of a needle thread from an upper workpiece surface to a lower workpiece surface at the first stitch of a seam to be produced by a sewing machine having a reciprocable needle, which carries the needle thread drawn-off from a spool by means of a thread take-up lever, and having at least one work presser lowerable onto and liftable from said workpiece, and having a rotatingly drivable hook, the back of which seizes and withdraws a needle thread loop for stitch formation, wherein said needed thread is held tightly between said needle and said thread take-up lever, while said needle thread loop is widened by said hook beak, so that the thread end is drawn by said hook beak through said workpiece.
Device for drawing a free end of a needle thread from an upper workpiece surface to a lower workpiece surface at a first stitch of a seam to be produced by a sewing machine, said sewing machine having a reciprocable needle, which carries the needle thread drawn-off from a spool by means of a thread take-up lever, and having at least one work presser lowerable onto and liftable from said workpiece, and having a rotatingly drivable hook, the beak of which seizes and withdraws a needle thread loop for stitch formation, wherein a thread clamp for said needle thread is stationarily provided between said thread take-up lever and said needle and wherein control means are provided for actuating said thread clamp, only while said needle thread loop of said first stitch is being widened by said hook beak, so that the thread end is drawn by said hook beak through said workpiece.
Dependencies are inferred from the claim text.