Patent ID: 8226522
Filing Date: 2012-07-24
Classification: F02C,F05D

Abstract:
1. A coupling system comprising: 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, wherein the main differential is a sunless epicyclic gear assembly comprising: a rotationally powered accessory engaged with the main differential; an epicyclic start differential operatively connected to the main differential; and a brake mechanism 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, wherein the brake mechanism is 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, and wherein the start differential is configured to transmit torque between the first main differential ring gear and the second main differential ring gear when the brake mechanism brakes a start differential carrier.