Molded rotor assembly for an alternator and method for making the same

An alternator for a vehicle comprising:

• a housing;
• a stator having windings and being supported by the housing;
• and
• a rotor assembly cooperating with and rotatable relative to the stator and the housing, the rotor assembly including an elongate rotor shaft, a pair of annular pole pieces axially aligned along and mounted on the rotor shaft with a region being defined between the pole pieces, a coil wire held within the region and having a plurality of turns and a pair of free ends, a pair of slip rings mounted on the rotor shaft, which are electrically connected to a respective pair of terminals, which in turn, are attached to the respective free ends of the coil wire to form a pair of respective connections, and a molded insert integrally molded to at least one of the pole pieces and at least partially filling the region between the pole pieces and encapsulating the coil wire to prevent relative movement between the coil wires.

A molded rotor assembly for a vehicle alternator, the rotor assembly comprising:

• an elongated rotor shaft having a longitudinal axis;
• first and second annular pole pieces axially aligned along and mounted spaced from each other on the rotor shaft defining a region between the pole pieces, each pole piece having an outboard axial face and along its radial periphery a plurality of circumaxially spaced and axially inboard-extending fingers, the fingers on each pole piece interleaving with the fingers on the other pole piece;
• a coil wire cooperatively held in the region between the pole pieces, the coil wire having a pair of free ends;
• a slip ring assembly having a pair of slip rings and a pair of terminals, each terminal connecting to a respective slip ring and to a respective free end of the coil wire to form a connection;
• and
• a molded body integrally molded to at least one of the pole pieces and encapsulating at least one connection.