Abstract: The annular cushion 25 interposed between the fixed housing 22, 23 and a swiveling exterior surface 27 in the shape of a spherical sector with relatively large radius of curvature of the bearing block 12, 15, 16, is in a relatively rigid and incompressible material, with low coefficient of friction surface, and has a transverse section wholly adapted to the section of the annular space arranged between the inner surface of the fixed housing 22, 23 and the swiveling exterior surface of the bearing block 12, 15, 16, this annular cushion consisting of two rings 25 spaced apart and arranged on each side of the transverse median plane of the swiveling exterior surface.

Abstract: The present invention relates to a suspension device for a transmission box (BT) of a rotary-wing aircraft, including bearing pieces (2) connected to the upper part (3) of the transmission box (BT), a suspension system (SU) which connects the lower part (9) of the transmission box (BT) to the fuselage (F) of the aircraft and which includes suspension leaves (5), and resonator means (7) which are associated respectively with the said bearing pieces (2) and which include a mass support (13) secured to the associated suspension leaf (5) and equipped with a flapping mass (MB). According to the invention, the said device additionally includes tuning means (18, 19) associated with the said resonator means (7) and capable of tuning their natural frequencies.

Abstract: A device for reducing the vibrations generated on the structure of a helicopter. The helicopter includes a structure with a tail boom and a fin. The structure has a longitudinal vertical mid-plane. The helicopter also has a main lift and propulsion rotor which generate an aerodynamic flow passing through the rotor and induce vibrations on the structure. A damping device for reducing the vibrations has a longitudinal chamber which is equipped with at least one central restriction, which has two elastically urged mobile lateral walls and which is full of a fluid representing an oscillating mass. The damping device is mounted in the tail boom close to the fin so that the direction of travel of the oscillating mass is at least substantially orthogonal to the longitudinal vertical mid-plane.