318 / | HD | ELECTRICITY: MOTIVE POWER SYSTEMS |
727 | DF | INDUCTION MOTOR SYSTEMS {12} |
830 | .~ With relatively movable cooperating motor parts to control energized motor {2} | |
831 | DF | .~.~> Axially movable cooperating parts |
832 | DF | .~.~> Dual stators, one or both angularly movable |