Abstract: The invention relates to a pivot pin (5) for an epicyclic gear train sliding bearing, the pivot pin having axially opposed, laterally open circumferential grooves (25a), providing flexibility to the pivot pin and which radially separate two axially opposite lateral end portions of a central shank from two lateral cantilevered portions (27a,27b) of the pivot pin. At least one of the cantilevered lateral portions is hollowed out by at least one recess (65a).

Abstract: A speed-reducing unit, particularly for transferring torque between a gas turbine and a fan in a turbine engine, includes an annular ring, at least one gear that is coupled to the ring, the ring including two annular half-rings that are offset relative to each other along the main axis of the speed-reducing unit and that are coupled with at least one gear, and a plate for supporting the two half-rings, in relation to which the two half-rings are rotationally fixed about the main axis of the speed-reducing unit. Each half-ring includes an internal helical tooth. Each half-ring is connected to the support plate so as to be able to be uncoupled from at least one gear when at least one gear exerts a disengaging action on each half-ring, with the amplitude of the action being greater than a determined amplitude value.

Abstract: Oil transfer tube for a system to control the regulation of a turbine engine propeller pitch, in particular of an aircraft, the tube being intended to be mounted coaxially inside a tubular shaft of the propeller, the tube having an elongated shape and including a first male longitudinal end part intended to be inserted in a female housing of a stator casing equipped with an oil supply circuit of the tube, and a second male longitudinal end part around which is intended to be mounted a hydrodynamic bearing to guide the tube in the shaft, wherein the first end part includes a free annular end with a convex rounded cross-section intended to bear axially against an annular bottom of said housing, and in that said second end part comprises an outer axial annular bearing surface of an inner ring of the bearing, the annular bearing surface presenting in cross-section a convex curved shape.

Abstract: A mechanical reduction gear is suitable for a turbomachine and, in particular, a turbomachine of an aircraft. The reduction gear includes a sun gear, a ring gear formed by two half-ring gears, planet gears arranged between the sun gear and the ring gear, and at least one shaft rotationally fixed to the ring gear. The reduction gear further includes an annular covering part that extends around the ring gear and is independently fixed by flanges and/or splines to each of the half-ring gears.

Abstract: A lubricating oil distributor for a mechanical reduction gear of a turbomachine, in particular of an aircraft, includes a body of generally annular shape around an axis X and includes first and second independent oil circuits. The first oil circuit has a first oil inlet connected by a first chamber to several oil outlets distributed on the body around the axis X. The second oil circuit has a second oil inlet connected by a second chamber to several oil outlets distributed on the body around the axis X. The first and second chambers extend circumferentially around the axis X at different diameters, wherein the first and second oil circuits are formed in the body and are respectively a recovery circuit and an oil supply circuit for toothing of the reduction gear.

Abstract: An impeller for a planet carrier of a epicyclic speed reduction gear of a turbine engine is fixed in rotation to the planet carrier and is rotatable about an axis of the reduction gear. The impeller has an annular shape about the axis and includes means for lubricating in particular planet gear bearings of the reduction gear. The lubricating means include an annular cavity located at the inner periphery of the impeller, wherein the impeller has an inner peripheral wall that closes the cavity in the radial direction. The impeller further includes an annular aperture that extends around the axis and opens in the axial direction into the cavity to supply lubricating oil thereto.

Abstract: A planet-carrier for a mechanical reduction gear of a turbine engine, in particular of an aircraft, this planet-carrier having a rotation axis and comprising axes for guiding the planet gears that are arranged around and parallel with the rotation axis, each guiding axis having a general tubular shape of which the outer periphery comprises only two coaxial and adjacent cylindrical tracks of the respective rollers of two annular rows of rollers, wherein each axis has an inner periphery that is substantially bi-conical and comprising two coaxial and adjacent frustoconical surfaces, these inner frustoconical surfaces converging towards one another and extending respectively radially inside the tracks.

Abstract: A device for mounting a ring gear of an epicyclic gear train, the ring gear including a front ring gear and a rear ring gear, the device including: a plurality of longitudinal guides; a front mounting forming a portion of circle, including: at least two holes for passing the guides; a plurality of first system for supporting and rotating the front ring gear relative to the axis thereof, movable between a first position in which the front ring gear is supported and can rotate relative to the axis thereof and a second position in which the front ring gear is not supported; a rear mounting forming a portion of circle, including: at least two holes for passing the guides; and a plurality of second system for supporting and rotating the rear ring gear relative to the axis thereof, movable between a third position in which the rear ring gear is supported and can rotate relative to the axis thereof and a fourth position in which the rear ring gear is not supported.

Abstract: Device of the reduction gear or differential type for a turbine engine of an aircraft. A central sun gear and a row of planet gears, each of the planet gears are rotationally guided by at least one bearing extending around a tubular support. The tubular support includes an inner cavity for the reception of oil and through-orifices for the passage of oil of the tubular support to the at least one bearing. A member for circulating the oil is mounted in the cavity and includes at least one oil duct intended to be connected to an oil supply. The oil is intended to flow from the at least one duct into the inner cavity to form an oil film in contact with said tubular support, and to flow through the orifices.

Abstract: The invention relates to an assembly comprising a drive gearbox (10) for an aircraft (1) and an accessory (30), the gearbox comprising: a connecting shaft (110) adapted to be driven by the propulsion system, a main shaft (120) adapted to be driven by the connecting shaft (110), and two bevel gears (122, 123) which are integral with the main shaft (120) and have different diameters (d122, d123), the accessory comprising: a high-speed accessory shaft (31) comprising a bevel gear (310), a low-speed accessory shaft (32) comprising a bevel gear (320), such that each gear (310, 320) on the accessory shafts (31, 32) meshes with one of the two bevel gears (122, 123) on the main shaft (120), so that the two accessory shafts (31, 32) rotate at different speeds relative to one another.

Abstract: A planet carrier for an epicyclic speed reduction gear, comprising a torque transmission member of longitudinal axis A and an annular cage extending around the axis A and connected to a longitudinal end of the member, said cage comprising two flanks extending essentially radially with respect to the axis A and connected by bridges, seats extending axially between the flanks and being intended for supporting planet gears mounted rotatably about the seats, characterized in that said bridges comprise bars which cross one another essentially in the shape of an X, and of which the ends located on the side of said member are connected to said member by a ring extending around said axis A and comprising a continuous internal annular channel.

Abstract: A propulsion unit for an aircraft, including an engine and a propeller and further a propeller with airfoils which is coupled to the propeller shaft and having electrical members consuming electrical power, sealing between a case and the propeller shaft being ensured by a dynamic seal housed between a rotating dynamic seal support secured to the propeller shaft and a dynamic seal support flange secured to an end portion of the case, the rotating dynamic seal support being secured to the propeller shaft and abutted against a bearing for supporting this propeller shaft, it is provided that the propulsion unit, in order to deliver electrical power to the electrical members, having a rotating transformer rotated by the propeller shaft and including a stator, a casing of which is secured to the dynamic seal support flange and a rotor, a casing of which is secured to this propeller shaft.

Abstract: An oil pipe cover for a mechanical reduction gear of a turbomachine, for example of an aircraft, is configured to be fixed to a planet carrier of the reduction gear and to be mounted on an axial end of a hydrodynamic bearing tubular support of a planet gear of the reduction gear. The oil pipe cover has an annular body extending around an axis (Y) and having a mounting central orifice on the axial end. The body has two diametrically opposed circumferential deflectors: a first deflector having a circumferential oil guiding surface located radially outwards with respect to the axis (Y), and a second deflectors having a circumferential oil guiding surface located radially inwards with respect to the axis (Y).

Abstract: A mechanical reduction gear is suitable for a turbomachine and, in particular, a turbomachine of an aircraft. The reduction gear includes a sun gear, a ring gear formed by two half-ring gears, planet gears arranged between the sun gear and the ring gear, and at least one shaft rotationally fixed to the ring gear. The reduction gear further includes an annular covering part that extends around the ring gear and is independently fixed by flanges and/or splines to each of the half-ring gears.

Abstract: A drive train for a helicopter, which includes an engine, a reduction gear and a main gearbox, the reduction gear including an output shaft, which are received in assembled front and rear housings, the output shaft being supported and guided rotatably by a plurality of rolling bearings, mounted in the housings. The drive train includes a redundant mount arranged around the output shaft and between a wall of the main gearbox and the front end of the front housing, and the redundant mount is configured, sized and attached to the wall of the main gearbox and to the front end of the front housing so as to create, if the front housing breaks, a secondary path for absorbing loads passing via the redundant mount, via the output shaft of the reduction gear and via the bearings.

Abstract: A planetary gearset having a first planet gear, a second planet gear, and pinion gears. The pinion gears mesh with the first planet gear and with the second planet gear, and each pinion gear is pivotally mounted around a shaft. A pinion gear carrier supports each shaft. Each shaft has a radially inner cylindrical portion mounted on the pinion gear carrier, a radially outer cylindrical portion about which the pinion gear is pivotally mounted and a flange extending radially from the radially outer cylindrical portion. The radially outer periphery of the flange is mounted on the pinion gear carrier. The radially outer cylindrical portion and the radially inner cylindrical portion are connected to each other by a radially extending connecting zone.

Abstract: A speed-reducing unit, particularly for transferring torque between a gas turbine and a fan in a turbine engine, includes an annular ring, at least one gear that is coupled to the ring, the ring including two annular half-rings that are offset relative to each other along the main axis of the speed-reducing unit and that are coupled with at least one gear, and a plate for supporting the two half-rings, in relation to which the two half-rings are rotationally fixed about the main axis of the speed-reducing unit. Each half-ring includes an internal helical tooth. Each half-ring is connected to the support plate so as to be able to be uncoupled from at least one gear when at least one gear exerts a disengaging action on each half-ring, with the amplitude of the action being greater than a determined amplitude value.

Abstract: An air-flow circuit for air flow through a bearing enclosure of a turbine engine, the air-flow circuit including a supply system arranged such as to supply the air into the bearing enclosure; a discharge system arranged such as to discharge at least some of the air from the bearing enclosure; an oil-removal system connected to the discharge system, the oil-removal system being capable of reducing the amount of lubricant contained in the air coming from the discharge system; and a compressor arranged between the discharge system and the oil-removal system, the compressor being capable of increasing the air pressure at the intake of the oil-removal system.

Abstract: A planet carrier for a speed-reducing unit with a planetary gear set is provided. The planet carrier generally includes a torque transmission part having a longitudinal axis and an annular cage extending about the axis and connected to one longitudinal end of the part. The cage may include two sides extending radially relative to the axis and connected by bridges, and seats extending axially between the flanks and configured to support planetary gears rotatably mounted about the seats. The curved members may include at least two corresponding bars each inclined relative to a longitudinal plane passing both through the axis and substantially through the corresponding bar.

Abstract: A reduction gear including an input shaft including an input gear, an output shaft including an output gear, and two intermediate transmission lines, each intermediate transmission line including an intermediate shaft including a first stage of teeth and a second stage of teeth, the stages rotating as one, and an additional gear for meshing respectively with the first stage of teeth and the input gear, or with the second stage of teeth and the output gear, and the reduction gear wherein the input gear or the output gear meshing with the additional gears is axially offset with respect to the stage of teeth of the intermediate shafts meshing with the additional gears.