Buttonhole sewing machine, has a fabric clamp at the presser foot or press roller carrier, to hold the fabric against flutter in the opening through the workpiece frame during stitching of thin/flexible materials

摘要

The buttonhole sewing machine has a fabric clamp (22) at the presser shaft or the carrier (13) for a press roller (14). It has a shaft (24) and a foot (25), which passes into an opening (11) in the fabric workpiece sliding frame (10). It is at a small vertical gap from the fabric, at least in the field where the second buttonhole side is stitched, and at a small horizontal gap from the side of the needle (6) towards the end stitching of the hole. The clamping foot, at the buttonhole sewing machine, has an effective rectangular surface with one end or side edge as far as the center axis of the frame opening, and with a small gap between the other side edge and the adjacent frame leg (31). The clamping foot can have a second effective surface between the field where the first buttonhole side (Ra1) is stitched and the adjacent leg (33) of the workpiece frame, with a gap width to the first surface which matches the width of the stitching. The clamping foot is below the movement path of the thread cutter/clamp (18). The clamp has a height adjustment.