Patent attributes
A coupling system includes a dynamoelectric device selectively operable as either a generator or an electric motor, a gas turbine engine, a main differential operably connected between the dynamoelectric device and the gas turbine engine, a rotationally powered accessory engaged with the main differential, an epicyclic start differential operatively connected to the main differential, and a brake mechanism. The brake mechanism is configured for selectively braking the epicyclic start differential when the dynamoelectric device operates as an electric motor to direct torque transmission to the gas turbine engine, and is further configured to cease braking the epicyclic start differential when the dynamoelectric device operates as a generator such that the main differential transmits torque to power the rotationally powered accessory and to the dynamoelectric device.