A coating machine 3 serving as a rotary atomizer comprises a hollow unrotary paint nozzle shaft 5 provided in the center of a motor shaft 10 serving as its rotary shaft. The paint nozzle shaft 5 is provided at a tip thereof with a gun-spray paint nozzle 5g and a gun-spray air nozzle 5f on the outside of the gun-spray paint nozzle 5g in the diametrical direction, and a needle shaft 21 is disposed in a paint passage 5b in the paint nozzle shaft 5 so as to serve as a valve mechanism for selectively supplying paint to either a bell cup 4 or the gun-spray paint nozzle 5g.