Formation of variable width cutting space buttonhole patterns in an electronically controlled sewing machine

摘要

A sewing machine is disclosed wherein the positional coordinates for successive stitch penetrations are stored in a memory having addressable locations corresponding to a plurality of operator selectable patterns, one of which is a buttonhole pattern. The buttonhole pattern includes two parallel rows of zig-zag stitches forming a pair of buttonhole side bars, the inner stitches of the side bars defining a cutting space therebetween and the outer stitches of the side bars defining the width of the buttonhole pattern. Means are provided for operator initiation of an override command to selectively alter the operation of the bight actuator to selectively control the position of only the inner side bar stitches so as to selectively vary the width of the cutting space while maintaining constant the overall buttonhole pattern width.