PURPOSE: To enable satisfactory power supply in a contactless state by forming a turbine, revolving shaft, rotary atomizing head and respective air bearings of a conductive material and impressing a high voltage on at least one of the air bearings to induce electric discharge.

CONSTITUTION: A revolving shaft 4 is held radially by a radial air bearing 9 and a turbine 5 is held axially by a thrust air bearing 12 respectively in a contactless state when the high-pressure air supplied through an air passage 16 for bearings into the air chambers 11, 14 of the bearings 9, 12 is ejected in the arrowmarked direction from porous bearings 10, 13. The slight air layer between the shaft 4 and the turbine 5 as well as the bearings 10, 13 induces electric discharge and a rotary atomizing head 6 is electrified via the shaft 4 when the high voltage from a high-voltage cable 27 is impressed via a housing 1 to the bearings 10, 13 while the turbine 5, the shaft 4 and the head 6 are under high speed rotation.