Rolling bearing unit with an encoder and protective cover for a vehicle wheel hub

A bearing unit (1) for a vehicle wheel has a radially outer stationary ring (10) and a radially inner rotatable ring (20) together defining a space (3). The stationary outer ring (10) is provided with an axial lug (14') and with a flange (14) transverse to an axis of rotation (A). An annular channel (16) is formed between the axial lug (14') and the flange (14) and is delimited axially by a bottom surface (17). An encoder (30) is fixed onto the inner ring (20) and extends outside of the space (3) and in front of the axial lug (14'). A protective cover (40) is provided with a side wall (42) to mount the cover (40) on the outer cylindrical surface (12) on the axial lug (14') so as to protect the encoder (30) and to close off the space (3) between the rings (10, 20). The cover (40) is equipped with a bent edge (43) arranged axially in abutment against the bottom surface (17) of the annular channel (16). A solidified sealant (50) is arranged between the cylindrical side wall (42) of the cover (40) and the tubular axial lug (14') so as to seal in a leaktight manner the cylindrical side wall (42) on the outer cylindrical surface (12).