Patent ID: 6833651
Filing Date: 2004-12-21
Classification: H02K

Abstract:
An electric machine, in particular an alternator for motor vehicles, comprising a stator (14) carrying a stator winding and a claw-pole rotor (15) that co-operates with said stator, comprising a pole core (17) surrounded by an excitation winding (16) and two claw-poles (27, 28) mounted on a rotor shaft (20), which said claw-poles are uniformly distributed around the periphery and have claw-pole fingers (34) that intermesh axially in alternate directions at a distance from one another, whereby at least one permanent magnet (35) is arranged between the adjacent claw-pole fingers (34) and is held by a non-magnetic holder (36) and supported against centrifugal forces, and whereby the holder (36) of the permanent magnets (35) is composed of a retaining ring (42) with a zigzag configuration, each of the axial sections (43) of which said retaining ring is located between two adjacent claw-pole fingers (34) and rest by means of their longitudinal sides on each lateral flank (37) of the claw-pole fingers (34), and each of the connection sections (44) of which said retaining ring connect two adjacent axial sections (43) with each other on the pole tip (40) of the claw-pole finger (34),wherein the retaining ring (42) engages in a longitudinal slit (38) on the lateral flanks (37) of the claw-pole fingers (34) by means the longitudinal sides of its axial sections (43).