The classification of sewing machines are many, more common is the distinction between trace and use. Sewing machine stitch can be summarized as lock stitch and chain stitch two categories. Lock stitch the most common, which consists of two suture lines, as rubbing rope intertwined with each other, the intertwined point in the middle of sewing material. Seen from the cross-section of the stitches, the two stitches are locked like two locks, so they are called lock stitches. This stitch used in the shrinkage of small cotton, wool fabric or leather sewing materials, the front and back the same shape, as a dotted line. Stitch distribution density, sewing fastness generally more than hand-stitching.
Chain stitches are self-connected or interconnected by the thread loops of the stitches. Commonly used are single-thread chain type, double-thread chain type and triple-thread stitches. This stitch is characterized by the flexibility of the stitch, which can stretch and shrink with the material without breaking the suture, which is suitable for the clothing of the elastic fabric of the thread or the loose-fitting product and the clothing blank of the seam.
In addition, the sewing machine in accordance with the purpose can be divided into household, industrial, service industry machines, according to the drive can also be divided into manual sewing machine, foot sewing machine, electric sewing machine