Power transmission gearbox and an aircraft
AssigneeAirbus Helicopters
InventorLionel Thomassey
Life of this patent
Estimating the term…
Abstract
A power transmission gearbox having at least one driving gear with spur teeth presenting a large radius. The gearbox includes at least one mechanical outlet drive system suitable for driving an accessory, the mechanical outlet drive system having a gear with face teeth referred to as an “accessory pinion”, the accessory pinion presenting a “small” radius (R2) lying orthogonally between each face tooth and its axis of rotation, the small radius (R2) being smaller than the large radius (R1).
Claims19
A power transmission gearbox having at least one driving spur gear that is movable in rotation about an axis of rotation, the driving spur gear with spur teeth and having a first radius lying orthogonally between each spur tooth of the driving spur gear and the axis of rotation, wherein the gearbox includes at least one mechanical outlet drive system suitable for driving an accessory, the mechanical outlet drive system comprising a driven face gear configured as an accessory pinion with face teeth, the face gear being movable in rotation about a drive axis that intersects the axis of rotation, at least one face tooth of the face gear being engaged with at least one spur tooth of the driving spur gear, the face gear having a second radius lying orthogonally between each face tooth of the face gear and the drive axis, the second radius being less than the first radius;
- wherein the gearbox includes at least one speed reduction stage suitable for driving a rotor, and the driving spur gear is a gear for setting the speed reduction stage into motion via at least one power transmission shaft, the at least one power transmission shaft movable in rotation about the axis of rotation of the driving spur gear and directly coupled to the driving spur gear and a gear of the speed reduction stage.
A power transmission gearbox for a rotorcraft, the gearbox comprising:
- a driving spur gear rotating about an axis of rotation, the driving spur gear having a top disk, a bottom disk, and an edge face extending in elevation along the axis of rotation, the edge face positioned between and connecting the top disk to the bottom disk, the edge face defining spur teeth of the driving spur gear, wherein the driving spur gear has a first radius lying orthogonally between each spur tooth of the driving spur gear and the axis of rotation;
- a speed reducing stage for driving a rotor of the rotorcraft, the speed reducing stage having a plurality of gears;
- a power transmission shaft directly coupled to the driving spur gear and to one of the plurality of gears of the speed reducing stage, the power transmission shaft constrained for rotation with the driving spur gear and the one of the plurality of gears of the speed reducing stage, the power transmission shaft rotating about the axis of rotation;
- and
- a mechanical outlet drive system for driving an accessory, the drive system having a driven face gear rotating about a drive axis and configured as an accessory pinion, the face gear having a top face, a bottom face, and an edge face extending in elevation along the drive axis, the edge face positioned between and connecting the top face to the bottom face, the face gear having face teeth extending in elevation from the top face, wherein the face gear has a second radius lying orthogonally between each face tooth of the face gear and the drive axis, the second radius being less than the first radius, wherein the drive axis intersects the axis of rotation, and wherein at least one face tooth of the face gear is in meshed engagement with at least one spur tooth of the driving spur gear.
A power transmission gearbox for a rotorcraft, the gearbox comprising:
- a driving spur gear rotating about an axis of rotation, the driving spur gear having a top disk, a bottom disk, and an edge face extending in elevation along the axis of rotation, the edge face positioned between and connecting the top disk to the bottom disk, the edge face defining spur teeth of the driving spur gear, wherein the driving spur gear has a first radius lying orthogonally between each spur tooth of the driving spur gear and the axis of rotation;
- and
- a mechanical outlet drive system for driving an accessory, the drive system having a driven face gear rotating about a drive axis and configured as an accessory pinion, the face gear having a top face, a bottom face, and an edge face extending in elevation along the drive axis, the edge face positioned between and connecting the top face to the bottom face, the face gear having face teeth extending in elevation from the top face, wherein the face gear has a second radius lying orthogonally between each face tooth of the face gear and the drive axis, the second radius being less than the first radius, wherein the drive axis intersects the axis of rotation, and wherein at least one face tooth of the face gear is in meshed engagement with at least one spur tooth of the driving spur gear;
- wherein the face gear is configured to move axially without influencing a bearing of the face teeth of the face gear against the spur teeth of the driving spur gear.
Dependencies are inferred from the claim text.