Rectifier cooling fin arrangement of vehicle AC generator

DETAILED DESCRIPTION A main object of the invention is to provide an improved vehicle AC generator that has a cooling arrangement to prevent the above problem.
Another object of the invention is to provide an improved rectifier unit that can be cooled effectively thereby to prevent temperature rise of a rotor supporting bearing.
According to a preferred embodiment of the invention, a vehicle AC generator includes a pair of front and rear frames fastened by a plurality of stud bolts at peripheral portions thereof, a stator having a multi-phase armature winding supported by the pair of frames, a rotor disposed inside the stator, a rectifier unit having a positive cooling fin, a negative cooling fin and a connection member.
The positive cooling fin is fastened by the plurality of stud bolts together with the front and rear frames separate from the negative cooling fin, and the connection member is disposed between the positive cooling fin and the negative cooling fin to insulate and hold the positive and negative cooling fins.
The negative cooling fin is preferably fastened to the rear frame by a plurality of stud bolts disposed at portions radially outer side of the positive cooling fin.