Patent ID: 7462964

Claim:
A fully-enclosed fan-cooled motor comprising: a stator core for a motor; a rotor core arranged at an inner periphery of said stator core, provided with a ventilation passage passing therethrough in an axial direction; a first bearing provided by means of a first bracket having a ventilation passage and a bearing bracket at one end of said stator core; a second bearing provided by means of a second bracket and housing at another end of said stator core; a rotor shaft on which said rotor core is mounted, freely rotatably supported by said first and second bearings; a ventilation passage linked with a ventilation passage of said first bracket, formed at an outer periphery of said stator core; a ventilation fan with vanes arranged on an outer surface thereof, mounted in a location on said rotor shaft between said first bearing and said rotor core; a partition member mounted on said rotor shaft between said second bearing and said rotor core; a first minute gap that blocks inflow of air into said motor between a front end of said ventilation fan and said first bracket; a second minute gap that blocks inflow of air into said motor between said front end of said partition member and said second bracket; an first aperture provided in a location at an inner periphery further inward than said vanes on said bearing bracket, wherein a current of cooling air is formed by introduction of external air by said ventilation fan from first aperture, said current of cooling air is again discharged to an outside through said ventilation passage of said first bracket and said ventilation passage on said outer peripheral side of said stator core; and a second aperture provided in said second bracket, wherein a current of cooling air is formed by introduction of external air by said ventilation fan from said second aperture, and said current of cooling air is again discharged to an outside through said ventilation passage of said rotor core, said ventilation passage of said first bracket and said ventilation passage on said outer peripheral side of said stator core.