Patent ID: 7242120

Claim:
An alternator comprising: a case including a rear bracket and a front bracket; a shaft having an end portion rotatably supported by a rear bearing disposed inside a rear bearing housing portion of said rear bracket; a rotor fixed to said shaft; a stator comprising, a stator core fixed to an inner wall surface of said case; and a stator coil configured by winding conducting wire onto said stator core; a rectifier disposed inside said rear bracket and electrically connected to said stator coil so as to convert alternating current generated in said stator coil into a direct current; and a fan fixed to said rotor, said fan cooling said rotor, said stator, and said rectifier by sucking in external air through a suction inlet in said rear bracket when said rotor rotates, said rectifier having a heat sink with a plurality of diode cooling fins for cooling a plurality of diodes, wherein: said suction inlet is formed in a vicinity of said rear bearing housing portion, so as to overlap with at least a portion of said plurality of diode cooling fins in an axial direction of said shaft; and a plurality of rear bearing cooling fins extending in a direction perpendicular to said shaft are formed to extend from an inner peripheral side of said suction inlet near said rear bearing housing portion.