An installation for mounting an outer sun gear in a reduction gear. The reduction gear includes an outer sun gear and planet gears meshing with an inner sun gear and with the outer sun gear and each mounted for free rotation around a pivot of a planet carrier. The outer sun gear includes a first crown having a first toothing and a second crown having a second toothing each meshing with first and second toothings of the planet gears. The installation includes a frame for supporting the reduction gear along its longitudinal axis, and first and second torque applicators, such as cylinders, that apply a torque around an axis of first and second rings, respectively. The first ring is configured to engage with the first crown of the outer sun gear and the second ring is configured to engage with a second crown of the outer sun gear.

A gas turbine engine includes, among other things, a propulsor section including a propulsor hub, the hub including a hub diameter supporting a plurality of propulsor blades. A compressor section includes a first compressor and a second compressor. A turbine section includes a first turbine and a second turbine. A geared architecture interconnects the first turbine and the propulsor hub. The geared architecture includes a gear volume. A compressor inlet passage is disposed annularly about the geared architecture.

A gas turbine engine includes, among other things, a propulsor section including a propulsor hub, the hub including a hub diameter supporting a plurality of propulsor blades. A compressor section includes a first compressor and a second compressor. A turbine section includes a first turbine and a second turbine. A geared architecture interconnects the first turbine and the propulsor hub. The geared architecture includes a gear volume. A compressor inlet passage is disposed annularly about the geared architecture.

A speed reducer includes a reduction mechanism, which includes an internal gear and an external gear meshing with the internal gear, and a first member, and transmits rotating motion decelerated by the reduction mechanism to a driven member. The speed reducer includes a protection member disposed between the first member and the driven member. The first member is formed of a material having specific gravity lower than at least one of the internal gear and the external gear and hardness lower than the driven member. The protection member is formed of a material having hardness higher than the first member.

A driving module including a driving source configured to generate power, a gear train including a decelerating gear set configured to receive driving power from the driving source and a ring gear attached to one side thereof, and a rotary joint including at least one planetary gear configured to rotate using power received from an output end of the decelerating gear set and to revolve along the ring gear is disclosed.

A modular high precision gear box arrangement includes first and second gear boxes. The first gear box has a first rotatable hollow wheel, a second fixed hollow wheel and at least one double planet having a first planet and a second planet arranged on a planet shaft. The first planet meshes with the first hollow wheel, the second planet meshes with the second hollow wheel, and the first hollow wheel is coupled with an output. The second gear box includes a fixed hollow wheel that is the second hollow wheel of the first gear box and at least one planet that is the second planet of the at least one double planet of the first gear box. The second gear box further includes an input for driving the planet shaft, wherein the input is arranged centrically or eccentrically to a central rotation axis of the gear box arrangement.

A modular high precision gear box arrangement includes first and second gear boxes. The first gear box has a first rotatable hollow wheel, a second fixed hollow wheel and at least one double planet having a first planet and a second planet arranged on a planet shaft. The first planet meshes with the first hollow wheel, the second planet meshes with the second hollow wheel, and the first hollow wheel is coupled with an output. The second gear box includes a fixed hollow wheel that is the second hollow wheel of the first gear box and at least one planet that is the second planet of the at least one double planet of the first gear box. The second gear box further includes an input for driving the planet shaft, wherein the input is arranged centrically or eccentrically to a central rotation axis of the gear box arrangement.

A hybrid-electric powertrain system for aircraft includes a gearbox having a first rotary shaft for output to drive an air mover for aircraft thrust. The system includes a first prime mover connected by a second rotary shaft to the gearbox for power input to the gearbox. Further, the system includes a second prime mover connected by a third rotary shaft to the gearbox. The second prime mover can have a hollow core, and at least one of the first and second rotary shafts passes through the hollow core and the third rotary shaft.

A hybrid-electric powertrain system for aircraft includes a gearbox having a first rotary shaft for output to drive an air mover for aircraft thrust. The system includes a first prime mover connected by a second rotary shaft to the gearbox for power input to the gearbox. Further, the system includes a second prime mover connected by a third rotary shaft to the gearbox. The second prime mover can have a hollow core, and at least one of the first and second rotary shafts passes through the hollow core and the third rotary shaft.

The embodiments disclose a method including transferring kinetic energy from a kinetic energy source to a flywheel storage device system, transferring all or a portion of the kinetic energy stored to a continually variable transmission planetary gear system, integrating a multiple axis mechanism kinetic energy transference device to the continually variable transmission planetary gear system, integrating multiple speed governors in the multiple axis mechanism kinetic energy transference device, coupling a computer controlled module to each of the speed governors, processing operational data with the computer controlled modules to determine a measured most efficient use of the kinetic energy for each operation, transmitting the operation measured most efficient use amount of the kinetic energy from the computer controlled module to the corresponding speed governor, transferring the amount of the kinetic energy through gears and output shafts/drive shafts to serve operations and storing surplus kinetic energy not needed for operations in the flywheel storage system.