Abstract: A system for transferring torque between a pair of independently, concurrently rotating shafts of a turbofan engine includes a magnetic gearbox. The magnetic gearbox has a first ring structure, a second ring structure and an intermediate ring structure. Each ring structure has an annular aperture therethrough and a plurality of permanent magnets embedded therein. The intermediate ring structure is disposed between the first and the second ring structures. Each ring structure is coaxially concentric with, and independently rotatable with respect to the remaining ring structures. The first and second ring structures are each coupled to separate ones of the rotating engine shafts, and the intermediate ring is operable to transfer torque between the pair of shafts. Preferably, the intermediate ring structure is coupled to a rotating machine. The rotating machine has a controller, and is operable for adjusting a ratio of torque transferred between the pair of shafts.

Abstract: An inside out generator disposed aft of the low-pressure turbine spool to generate power for the electrical demands of an aircraft system. The low-pressure turbine discharge flow is used to drive the power turbine, which is coupled to the generator. The generator is able to extract power at idle conditions of the aircraft engine from ducting the discharge through the inside out generator. The system eliminates the placement of a generator in the hot gas path of the discharge, and enables the injection of power directly to the accessory gear box of the engine.

Abstract: A system for transferring torque between a pair of independently, concurrently rotating shafts of a turbofan engine includes a magnetic gearbox. The magnetic gearbox has a first ring structure, a second ring structure and an intermediate ring structure. Each ring structure has an annular aperture therethrough and a plurality of permanent magnets embedded therein. The intermediate ring structure is disposed between the first and the second ring structures. Each ring structure is coaxially concentric with, and independently rotatable with respect to the remaining ring structures. The first and second ring structures are each coupled to separate ones of the rotating engine shafts, and the intermediate ring is operable to transfer torque between the pair of shafts. Preferably, the intermediate ring structure is coupled to a rotating machine. The rotating machine has a controller, and is operable for adjusting a ratio of torque transferred between the pair of shafts.

Abstract: An inside out generator disposed aft of the low-pressure turbine spool to generate power for the electrical demands of an aircraft system. The low-pressure turbine discharge flow is used to drive the power turbine, which is coupled to the generator. The generator is able to extract power at idle conditions of the aircraft engine from ducting the discharge through the inside out generator. The system eliminates the placement of a generator in the hot gas path of the discharge, and enables the injection of power directly to the accessory gear box of the engine.

Abstract: A fail-fixed servovalve is provided for use in a digital control system. The servovalve is comprised of a deflecting means which deflects a jet pipe in response to an electrical input signal. Fluid flowing through the jet pipe causes a spool to translate within a sleeve, thereby allowing pressurized fluid to flow through selected ports within the sleeve to control the movement of an output piston. The output of the servovalve is essentially linear over the primary range of digital input currents with the output being zero when the input current is either zero or in excess of the maximum rated current for the servovalve.

Abstract: A turbine is stabilized in high speed, high altitude flight conditions by reducing the maximum augmenter fuel/air ratio in response to certain pressure and temperature conditions. Temperatures and pressures indicative of those at the combustor are sensed and the augmenter fuel schedule is accordingly modified to a level which provides reduced fuel/air ratios and stable burning conditions.