With the highly-rigid feed mechanism with servo control, stitch point is very precise and feed drifting, which is specific to electronic sewing machines, does not occur even in high-speed sewing of weighty mate-rials. The servo control also makes home position de-tection unnecessary. The shape of the looper, the thread take-up amount and some other parts have been reviewed. Skipped stitches and insufficient thread tightening due to a change of thread tension are reduced, regardless of types of threads. The range of sewing capability has been enlarged.