A planet-carrier for an epicyclic gearing is provided with a ring having a plurality of plate sectors and a plurality of connection sectors, alternating with one another about a first axis; a connection structure connects in an angularly fixed manner the connection sectors to a rotating member or to a static member; the planet-carrier is also provided with a plurality of pins, which are fixed with respect to the plate sectors and protrude in opposite directions from the plate sectors along respective second axes, parallel and eccentric with respect to the first axis; each pin has two coaxial outer surfaces, adapted to support respective planet gears of the gearing and symmetrical to each other with respect to a symmetry plane orthogonal to the first axis; the plate sectors are asymmetrical with respect to this symmetry plane.

The present disclosure relates to an epicyclic gear train comprising a driving member (3), driving a plurality of planetary gears (7). Each planetary gear is attached to a planetary holder and meshes with at least one ring gear. Thereby the ring gear or the planetary holder is made to rotate about a central axis (21) of the epicyclic gear train. The other one of the ring gear and the planetary holder is fixed to a stationary part (5) of the gear train. The planetary gears (7) are attached to the planetary holder, each via at least one planetary connector (17) which is rotatable around an axis (24) offset from and parallel to the planetary axis (23), such that turning said at least one planetary connector alters the distance between the central axis (21) and the planetary axis (23) by means of an eccentric connection. The planetary connectors are rotatingly pre-tensioned to apply a pressure on the planetary axis (23) away from the central axis (21), and said at least one planetary connector is attached to the planetary holder by a bearing (27).

A high ratio traction drive transmission includes a sun roller, a traction ring, a plurality of traction planets in contact with the sun roller and the traction ring, at least one reaction roller in contact with at least one of the traction planets, and a carrier assembly coupled to at least one of the traction planets and the at least one reaction roller. The sun roller has a first longitudinal axis and the traction ring is aligned coaxially with a second longitudinal axis, wherein the first longitudinal axis is radially offset from the second longitudinal axis.

A planet wheel assembly includes a planet shaft, a planet wheel having radial contact surfaces and axial contact surfaces, bushings connected to the planet shaft, radial sliding elements between radial contact surfaces of the bushings and the radial contact surfaces of the planet wheel, and axial sliding elements between axial contact surfaces of the bushings and the axial contact surfaces of the planet wheel. The planet wheel is shaped to constitute a circumferential projection which protrudes radially towards the planet shaft, is axially between the radial sliding elements, and forms the first and second axial contact surfaces of the planet wheel. This arrangement, where the radial sliding elements are axially outmost and the axial sliding elements are on the middle, improves the ability of the radial sliding elements to act against forces tilting the planet wheel.

A device for driving at least one wheel of an aircraft landing gear is provided. The device includes at least one wheel having a rim, an electric motor having a shaft, and a mechanical transmission system for mechanical transmission between the shaft of the motor and the rim. The mechanical transmission system includes a mechanical reduction gear. The mechanical reduction gear includes a sun gear secured in rotation to the shaft and having an external toothing, a stationary ring gear with internal toothing, a movable ring gear secured in rotation to the rim and having an internal toothing, and planet gears that are meshed with the sun gear and each have two external toothing meshed respectively with the toothing of the stationary and movable ring gears.

A gas turbine engine including a first frame including a first mount member defining a stiffness K.sub.1; a second frame including a second mount member defining a stiffness K.sub.2 and a third mount member defining a stiffness K.sub.3; and a gear assembly. The gear assembly includes a first rotatable component, a second rotatable component, and a torque transfer component. The first mount member is coupled to the first rotatable component. The second mount member is coupled to the second rotatable component. The third mount member is coupled to the torque transfer component. The stiffness K.sub.1 is less than or equal to 10% of the stiffness K.sub.3.

A reducer includes a reducer housing, an input shaft, an inner gear ring, a cycloidal gear, an output flange, and a plurality of pin shafts. The inner gear ring is fixed to the reducer housing. An eccentric cam is provided on the input shaft. The cycloidal gear is mounted on the eccentric cam via an arm bearing and meshes with the inner gear ring. The cycloidal gear is provided with a plurality of pin holes distributed in the circumferential direction thereof. The reducer further includes a support frame having a central shaft hole. The input shaft passes through the central shaft hole. Each pin shaft passes through the corresponding pin hole and both ends are connected to the output flange and the support frame respectively.

A planetary gear train includes a central wheel, a gear and a carrier, geometrically coupled by a closed eccentric connection that locks the gear. The locking is provided by displacement of the carrier in relation to the gear in a circumferential or tangential direction, when the gear's rotation speed is lower than the carrier's rotation speed. When there is more than one locking gear, the carrier's displacement in relation to the gear can be identical or different. The eccentric connection can be designed as an eccentrically disposed projecting section of outer surface of either the gear or the carrier, conjugated with an opening or slot formed in the carrier or gear, or as an eccentric element having eccentrically disposed projecting sections that may be designed as a single rolling body. The gear train provides for locking (blocking) the gear, as well as for transmitting rotational movement thereby extending its use.

An aircraft capable of hovering is described, comprising a motor member; a rotor connected to the motor member; a transmission shaft rotatable around a first axis and adapted to drive the rotor; and a transmission interposed between the motor member and the rotor and comprising a planetary gear formed by a sun rotatable around a second axis; a crown that is angularly fixed; and two satellites meshing, each, with the crown and the sun, and rotatable around respective third axes, which are, in turn, rotatable around the second axis; and a satellite carrier rotatable around the second axis and comprising two first pins with respect to which the satellites are rotatable around the respective third axes; the transmission comprises an interface, angularly integral with the satellite carrier around the second axis and said transmission shaft around the first axis; the interface being coupled to said satellite carriers and the transmission shaft so as to allow an angular misalignment between the second axis and a portion of the interface.

An epicyclic gear train including a central sun gear, an outer ring gear, and a number of planet gears which are mounted to a planet carrier. The planet carrier includes a centrally disposed torque transfer coupling with a torque transmission point at an axial end thereof. First and second carrier plates extend radially from the torque transfer coupling and are axially spaced apart to support the planet gears therebetween at aligned gear mounting points. The first carrier plate is closer to the torque transfer point than the second carrier plate. The second carrier plate has a stiffness that is greater than that of the first carrier plate.