A hub-bearing unit with an axis of rotation includes a stationary, radially external ring, a radially internal flanged hub, rotatable about the axis and including a first shoulder, a second shoulder, a first relief groove, and a section (SR) radially opposite the first relief groove. At least one row of rolling bodies is interposed between the external ring and the flanged hub. The hub-bearing unit includes a first radial ball bearing and a second radial ball bearing interposed between a stem of a constant velocity joint and the flanged hub and opposite the first shoulder and the second shoulder. The second ball bearing mounts inside a seat of the flanged hub and a spacer axially abuts the second shoulder and mounts inside the seat between the second shoulder and the second ball bearing. The seat includes a second relief groove formed in an axially external position relative to section (SR).

A drive axle assembly includes a wheel bearing mounted to an axle housing, a shaft assembly including a first shaft on an inboard side thereof to which a driving force of a power train is transmitted, and a second shaft on an outboard side thereof which is shaft-connected to the inside of the axle housing by a constant-velocity joint and is separably assembled to the first shaft, and a boot assembly including a first end portion fixed to an external ring of the wheel bearing and a second end portion assembled to the shaft assembly to be rotatable relative to the shaft assembly, and configured to restrict rotation of the boot and prevent foreign substances from being introduced therein.

A wheel drive assembly for transferring propelling torque from a source shaft to a wheel, the source shaft receiving torque from a motion actuator. The wheel drive assembly includes a wheel-hub, adapted to have the wheel mounted thereon, the wheel-hub being arranged about a longitudinal axis, which is adapted to coincide with a rotation axis of the wheel. The wheel drive assembly further includes a drive axle and a constant velocity (CV) joint mounted onto an outer end of the drive axle. The CV joint connects the drive axle to the wheel-hub. An outermost surface of the CV joint is disposed outwardly of an outermost surface of the wheel hub, along the longitudinal axis of the wheel-hub.

In a wheel bearing device (1): a ratio of an axial direction length C of a recessed portion (3h) formed in a through-hole (3e) of a hub ring (3) to a pitch circle diameter A of the recessed portion formed in an inner circumferential surface of the hub ring is 0.7(C/A)1.07; a ratio of an axial direction distance E between a flange surface (3j) of a wheel attachment flange (3b) and an inner end surface (4b) of an inner race (4) to an inter-ball pitch F between an inner ball row (5) and an outer ball row (6) is 2.85(E/F); and a ratio of the axial direction distance E to a pitch circle diameter D of balls (8) is 0.8(E/D) 0.94. The wheel bearing device makes it possible to suppress an increase in weight while suppressing generation of abnormal sounds.

A motor vehicle drive wheel assembly includes a fixed subassembly that includes two outer raceways; a rotating subassembly that includes a wheel hub, two inner raceways and two rows of rolling bodies that are arranged in two pitch planes PP1 and PP2. One of the inner raceways is formed on a rolling bearing ring bearing against a shoulder of the wheel hub along a bearing interface having an outer circumference of large diameter.