Buttonhole stitch control in an automatic electronic sewing machine

摘要

In an automatic electronic sewing machine including a read only memory (ROM) and a random access memory (RAM), the read only memory (ROM) stores pattern data for performing buttonhole stitch operation in the forward direction and pattern data for performing buttonhole stitch operation in the backward direction. A first control switch functions to conduct the buttonhole stitch operation in the forward direction by a desired length selected by the operator. A storage means is provided for storing the length information of the buttonhole stitch formation in the forward direction, or the repetition number of a unit pattern in the forward direction. A second control switch functions to conduct the buttonhole stitch operation in the backward direction by the length stored in the storage means.