Patent ID: 11873765
Assignee: ROLLS-ROYCE NORTH AMERICAN TECHNOLOGIES, INC.
Field: Engines, pumps, turbines (Mechanical engineering)
Classification: CPC F | IPC F

Claim 10:
11. A method of rotating a rotor of a gas turbine engine system, the method comprising: providing a gas turbine engine having a rotor and a turbine coupled with the rotor for rotation about an axis with the rotor, an accessory gearbox connected with the rotor of the gas turbine engine and configured to be driven by the rotor of the gas turbine engine during operation of the gas turbine engine to power auxiliary sub-systems for the gas turbine engine, and a flywheel powered barring engine system connected with the accessory gearbox and configured to drive rotation of the rotor of the gas turbine engine about the axis via the accessory gearbox after the gas turbine engine is shut down, the barring engine system including: an accessory gearbox shaft coupled with the accessory gearbox and configured to be driven by and to drive the accessory gearbox, a flywheel shaft assembly configured to store rotational energy from the accessory gearbox during operation of the gas turbine engine, the flywheel shaft assembly including a flywheel shaft and a flywheel coupled with the flywheel shaft for rotation therewith, and a barring engine configured to selectively allow the accessory gearbox shaft to drive the flywheel shaft and the flywheel shaft to drive the accessory gearbox shaft, the barring engine includes a barring shaft assembly, a first overrunning clutch, and a second overrunning clutch, the first overrunning clutch being coupled between the accessory gearbox shaft and the flywheel shaft and configured to transfer rotational energy from the accessory gearbox shaft to the flywheel shaft in response to the accessory gearbox shaft rotating at a rotational speed greater than a rotational speed of the flywheel shaft, and the second overrunning clutch being coupled between the barring shaft assembly and the accessory gearbox shaft and configured to transfer rotational energy from the barring shaft assembly to the accessory gearbox shaft in response to the barring shaft assembly being driven by the flywheel shaft at a rotational speed greater than the rotational speed of the accessory gearbox shaft to cause the flywheel shaft to drive rotation of the rotor of the gas turbine engine about the axis via the accessory gearbox shaft
operating the gas turbine engine so that the rotor of the gas turbine engine drives the accessory gearbox,
driving the flywheel shaft via the accessory gearbox shaft so that rotational energy from the accessory gearbox is stored in the flywheel,
shutting down the gas turbine engine, and
driving the accessory gearbox shaft via the flywheel shaft so that the flywheel drives rotation of the rotor of the gas turbine engine.