The Japanese had just as much to do with the designing of, or engineering of if you will, of the mechanics of sewing machines as anyone else from the 50s on. They took the 15 class system and ran with it. As far as I'm concerned, by the late 50s Japanese machines were being better designed and built than any Singer machine and they only continued to get better. If that weren't true, Janome and Brother wouldn't be where they are today.
Cari