| 摘要 |
The presser bar of a conventional straightstitch sewing machine supports a base on which a lever pivots vertically. The lever is coupled to the needle bar and intermittently rotates a ratchet wheel, with a cam which causes horizontal pivoting of a fabric presser foot and lateral reciprocation of the fabric to form zigzag stitches. Specifically the cam operates in an opening in a horizontally swingable member detachably secured to the pressor foot. A straight-stitch machine easily converted for zigzag stitching. Pref. the lever has a spring-loaded finger which operates the ratchet wheel.
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