A pivoting power transmission unit is provided for driving a tiltable rotor of
a convertible aircraft. The casing of the pivoting transmission unit comprises
a lower casing, by which the casing is able to pivot on a support by two bearings
each having a stationary part integral with the support and a swivelling part.
The lower casing is assembled to an upper casing in which a drive shaft connected
in rotation to gears housed in the casing is mounted so as to rotate about an axis
of rotation perpendicular to the pivot axis of the casing. The upper casing is
supported by an arrangement configured to transfer to the support via said bearings
load/thrust forces experienced by the drive shaft during use.
