Patent ID: 7670118

Claim:
A hot-gas blowing fan, comprising: a heat resisting impeller cantilevered by a rotating shaft; a bearing attached to the rotating shaft; a heat insulating layer disposed between the impeller and the bearing, the heat insulating layer including a first radial face that faces the impeller and an inner circumferential face that faces the rotating shaft; a cooling portion disposed between the heat insulating layer and the bearing, and the cooling portion includes a cooling fluid to remove heat from the bearing and the rotating shaft without contacting the bearing or the rotating shaft; a first magnetic coupling disposed on a shaft end of the rotating shaft at a side opposite to the impeller; a second magnetic coupling configured to be mated with the first magnetic coupling and disposed on a shaft end of a driving shaft of a motor; a non-magnetic partition wall disposed between the first magnetic coupling and the second magnetic coupling; and a collar positioned between the first radial face of the heat insulating layer and the impeller and positioned between the inner circumferential face of the heat insulating layer and the rotating shaft, wherein the collar comprises a different material than the heat insulating layer such that the collar prevents the heat insulating layer from contaminating a process gas flowing inside the hot-gas blowing fan, wherein a space surrounding the rotating shaft is hermetically sealed from an exterior of the hot-gas blowing fan by the non-magnetic partition wall and a casing.