Abstract: A plain bearing for a planet gear of a turbomachine mechanical reduction gear, the plain bearing having an annular barrel with an axis which delimits at least one central bore centred on the axis, and the barrel having annular grooves which extend around the axis and which open out axially in opposite orientations at the axial ends of the barrel, each annular groove being delimited by two coaxial internal and external walls of the barrel connected by a transverse bottom wall which has at least one opening which opens into a cavity which is formed in the barrel between said the at least one central bore and a periphery of the barrel, characterised in that wherein each cavity is closed by a sealing seal.

Abstract: A mechanical gearbox for turbomachine, in particular for aircraft. The gearbox includes a sun gear including an external toothing, a ring gear including an internal toothing, and planet gears which are meshed with the sun gear and the stationary ring gear. The planet gears are carried by a movable planet carrier and each having external toothings of different diameters. The movable planet carrier includes a movable ring gear which carries an internal toothing and which is independent of the stationary ring gear, each of the planet gears being meshed with the sun gear and the stationary and movable ring gears.

Abstract: A method for manufacturing a mechanical reducer for an aircraft turbomachine including a central pinion, an outer crown, N planet pinions, where N?3, each planet pinion including a first stage meshing with the central pinion, and a second stage meshing with the outer crown, the method including the assembly marking, wherein N teeth of the central pinion are marked, and N pairs of teeth of the first stage of each planet pinion are marked, the N planet pinions each being marked identically, and the assembly of the mechanical reducer, so that the teeth of the pairs of marked teeth of the first stage of each planet pinion are disposed on either side of a marked tooth of the central pinion.

Abstract: A jet for lubricating a piece of a turbomachine for an aircraft such as an airplane, including a circulation duct for flowing a pressurised fluid, includes a first duct chamber, a second duct chamber, a first nozzle for passing between the first duct chamber and the second duct chamber, the first nozzle having a fixed minimum passage cross-section, and a second nozzle for passing from the second chamber to the outlet port formed by the second nozzle, the second nozzle including a fixed minimum passage cross-section. The ratio of the cross-section of the first nozzle to the cross-section of the second nozzle is between 0.16 and 3.61.

Abstract: A method for manufacturing a mechanical reducer for an aircraft turbomachine including a central pinion, an outer crown, N planet pinions, where N?3, each planet pinion including a first stage meshing with the central pinion, and a second stage meshing with the outer crown, the method including the assembly marking, wherein N teeth of the central pinion are marked, and N pairs of teeth of the first stage of each planet pinion are marked, the N planet pinions each being marked identically, and the assembly of the mechanical reducer, so that the teeth of the pairs of marked teeth of the first stage of each planet pinion are disposed on either side of a marked tooth of the central pinion.

Abstract: A mechanical gearbox for an aircraft turbomachine includes a sun gear having an axis (X) of rotation, a ring gear around the sun gear, and planet gears meshed with the sun gear and the ring gear. Each planet gear has a first toothing meshed with the sun gear and a second loathing meshed with the ring gear. The first toothing includes a series of upstream teeth and a series of downstream teeth located on either side of a plane (H) perpendicular to the axis (X) of rotation of the sun gear. The second toothing includes a series of upstream teeth and a series of downstream teeth located on either side of the plane (H) and separated from one another by the first toothing, these teeth being parallel to one another and to the axis (Y) of rotation of the planet gear.

Abstract: A mechanical gearbox for turbomachine, in particular for aircraft. The gearbox includes a sun gear including an external toothing, a ring gear including an internal toothing, and planet gears which are meshed with the sun gear and the stationary ring gear. The planet gears are carried by a movable planet carrier and each having external toothings of different diameters. The movable planet carrier includes a movable ring gear which carries an internal toothing and which is independent of the stationary ring gear, each of the planet gears being meshed with the sun gear and the stationary and movable ring gears.

Abstract: A mechanical gearbox for an aircraft turbomachine includes a sun gear having an axis (X) of rotation, a ring gear around the sun gear, and planet gears meshed with the sun gear and the ring gear. Each planet gear has a first toothing meshed with the sun gear and a second toothing meshed with the ring gear. The first toothing includes a series of upstream teeth and a series of downstream teeth located on either side of a plane (H) perpendicular to the axis (X) of rotation of the sun gear. The second toothing includes a series of upstream teeth and a series of downstream teeth located on either side of said plane (H) and separated from one another by said first toothing, these teeth being parallel to one another and to the axis (Y) of rotation of the planet gear.

Abstract: A jet for lubricating a piece of a turbomachine for an aircraft such as an airplane, including a circulation duct for flowing a pressurised fluid, includes a first duct chamber, a second duct chamber, a first nozzle for passing between the first duct chamber and the second duct chamber, the first nozzle having a fixed minimum passage cross-section, and a second nozzle for passing from the second chamber to the outlet port formed by the second nozzle, the second nozzle including a fixed minimum passage cross-section. The ratio of the cross-section of the first nozzle to the cross-section of the second nozzle is between 0.16 and 3.61.