Patent ID: 7038340

Claim:
An AC generator for a vehicle, comprising: a housing; first and second bearings held by the housing; a stator disposed in the housing; a rotor operatively coupled to the stator, and having a rotation shaft that is rotatably supported by the first and second bearings; and a multiple-helical wave washer disposed to apply a pre-load to at least one of outer rings of the first and second bearings; the housing includes a first frame that has a first bearing box for holding the first bearing, and a second frame that has a second bearing box for holding the second bearing; the stator is disposed between the first frame and the second frame; the first bearing is disposed in the first bearing box with a clearance between the first bearing and a side wall of the first bearing box in an axial direction of the rotation shaft; the side wall of the first bearing box is constructed with a side wall portion of the first frame and is made of aluminum, and a washer box made of iron is disposed in the first bearing box and contacts an inner surface of the side wall portion of the first frame; and the multiple-helical wave washer is disposed in the clearance, and contacts an outer ring of the first bearing and the washer box.