What happened to the old sewing machine that the feed teeth only move up and down, not back and forth?

The spindle is broken.

Sewing machine, also known as tailor's machine or sewing machine, is a machine that uses one or more sewing threads to form one or more stitches on the sewing material, so that one or more layers of the sewing material are interwoven or sewn together.

Consisting of four parts: the head, the seat, the drive and the accessories. The sewing machine was invented during the first industrial revolution with the main purpose of reducing the amount of hand sewing in garment factories.

In China in the late 1950s, the sewing machine became one of the so-called Big Four. Sewing machines can sew cotton, linen, silk, wool, man-made fibers and other fabrics and leather, plastic, paper and other products, sewing neat and beautiful stitch, flat and firm, fast sewing speed, easy to use.