Fluid rotary machine

A fluid rotary machine comprising:

• a rotor electrical device including a main shaft rotatable about a main axis,
• fluid means including a plurality of impellers and casing means enclosing said impellers and defining passages for fluid to be sucked into and discharged from said impellers, said impellers having respective impeller rotational axes aligned with said main axis,
• and transmission means for operatively drivingly connecting said main shaft with said impellers, said transmission means including a plurality of output shafts which rigidly support respective ones of said impellers for rotation therewith and a gear train for gearingly connecting the main shaft with said output shafts to rotate said output shafts at respective predetermined rotational speeds as compared to the rotational speed of said main shaft, said output shafts having rotational axes aligned with said main axis,
• said gear train including an output shaft gear mounted rigidly on each of said output shafts at an end thereof for rotation therewith and at least three support gears meshed with and supporting said respective output shaft gears to thereby rotatably support said end of said respective output shafts by said support gears without the interposition of bearing means,
• wherein at least one of said impellers is disposed at each side of said rotary electric device.