Electric fan and especially a fan of the flat type

摘要

The fan rotor has an axial passage for a stationary shaft, one end of which is secured to the housing. The other end is covered by a plug for sealing-off the axial passage near the impeller hub. An external cover-plate of heat-conducting material is placed over the plug and applied in good thermal contact with the annular end portion of the rotor which is associated with the impeller.