Device for the transmission of rotary motion and the transfer of at least one fluid medium

A device for transmission of rotary motion and transfer of at least one fluid medium which comprises:

• a planetary gear train for the transmission of rotary motion about a main axis which has at least one reduction stage which is provided with a sun gear, which rotates about said main axis, and a toothed ring gear which are mutually concentric and between which at least two planetary gears are engaged which are supported in rotation at least about respective longitudinal axes which are parallel to said main axis by a planetary gear carrier, the planetary gear train being provided with a driving input sun gear and with an output ring gear and with an output planetary gear carrier, of which one can move in rotation about said main axis with respect to the other, and
• a rotary joint positioned radially outward of the planetary gear train and which extends externally to said planetary gear train, the rotary joint adapted for the transfer of the at least one fluid medium via a plurality of annular chambers, each of which extending substantially radially with respect to the main axis and with a different radial depth with respect to the main axis so that corresponding ones of a plurality of channels extending therefrom longitudinally and substantially parallel with the main axis do not interfere with other ones of the plurality of annular chambers.