PURPOSE: To blow clean gas by providing a device with a rotor member furnished with vanes and with a stator member which rotatably supports the rotor member, radially supporting the rotor member by means of dynamic pressure with respect to the stator member, concurrently making up the radially facing sections of both of the rotor and the stator member of ceramics, and thereby eliminating the occurrence of wear dust.

CONSTITUTION: A columnar stator member 2 made of fine silicon carbide sintered material is provided in a cylindrical casing 1, and a cylindrical rotor member 3 enclosing the stator member 2 is concurrently housed therein. The rotor member 3 is supported while floating in the axial direction by means of the magnetic repulsive force of opposite magnets 4 and 5. In addition, a plurality of field magnets 6 is fitted in a circular shape onto the outer circumferential surface of the rotor member 3. Meanwhile, a plurality of electromagnetic coils 7 is provided for the inner circumferential surface of the casing 1. Furthermore, a cylindrical opposite member 8 made of porous silcon carbide sintered material is attached to the inner circumferential section of the rotor member 3 so as to be faced to the outer circumferential surface of the stator member 2 on which a plurality of herringbone shaped dynamic grooves 9 is engraved. And a plurality of air blasting vanes 12 is thereby provided for a rotating board 11 integrated with the rotor member 3.