A bearing unit for a vehicle wheel hub is associated with a rotation
sensing device and an electromagnetic inductive coupling. The rotation
sensing device comprises an impulse ring (18) secured for rotation with
the rotatable race (13) of the bearing unit by means of a rotatable
annular carrier (19), and a magnetic/electric transducer (20) mounted to
the stationary race (12) of the bearing unit by means of a stationary
annular carrier (21) and operatively facing the impulse ring (18). The
electromagnetic inductive coupling comprises a stationary coil (24)
electrically connectable to a power supply (32) and carried by the
stationary annular carrier (21), and a rotatable coil (25) electrically
connectable (26) to an electric or electronic device mounted on the
wheel. The rotatable coil (25) is carried by the rotatable annular
carrier (19) and is electromagnetically linked to the stationary coil
(24).