US 4,219,739 A · Starter motor-alternator apparatus

Abstract

A starter-motor, and alternator-generator apparatus for an internal combustion or gas turbine engine wherein the major electro-magnetic circuit of the apparatus is utilized for both the starting and generating functions is disclosed. The rotor may have two windings on it, a main rotor winding that acts as both a starter armature winding and an alternator field winding, and a small exciter armature winding. For slip ring machines the exciter is eliminated. The main rotor winding is wound in progressive simplex lap. The exiter armature or slip rings are connected to this winding at the equalizer connections through a rectifier and automatically activated switch circuit. During starter-motor operation, the main rotor winding is connected in series with its starter field winding through a commutator in a conventional series connected DC machine, and the exciter-armature winding or slip rings are disconnected from the main rotor winding. During alternator-generator operation, the brushes are lifted off the commutator and the exciter-armature winding or slip rings are connected to the main rotor winding.

Claims10

Dependent claims

An electric machine having a rotor and stator portion and adapted to be driven by DC to produce torque for starting an engine, and when driven by such engine, to produce an AC electric output, said machine comprising:

a main rotor winding;
a main stator winding;
a heavy current commutation system including a commutator and brushes connecting said main rotor winding and said main stator winding in series for the production of torque to start said engine;
an exciter armature winding located on said rotor portion for joint rotation with said main rotor winding;
an exciter field winding on said stator portion coacting with said exciter armature winding;
a controlled rectifier set connected between the exciter-armature winding and the main rotor winding for feeding DC from AC generated by said exciter-armature winding to said main rotor winding;
and
an automatically activated gate switching means connected between said controlled rectifier set and said main rotor winding, said switch means being open when said machine is driven by DC to produce torque and closed when driven by said engine to produce an AC electric output.

5 more elements

Dependencies are inferred from the claim text.

Starter motor-alternator apparatus

Life of this patent

Starter motor-alternator apparatus

Life of this patent

Abstract

Claims10