The AC generator has a magnetic pole core (3) secured to a rotary shaft (2) driven by the engine and enclosed by a stator core (7) wound with a stator coil system. This has two coil end sections (51, 52) projecting from the stator coil system on both sides in the longitudinal direction of the shaft. The stator core is held between two clamp plates (8, 10), with a rectifier (13) and voltage regulator (14) associated with one of the clamp plates (10) which has a cooling fluid channel structure for the rectifier, the generator itself cooled via a cooling air stream provided by a cooling fan (25).
