A preload inspection method with which a preload value can be calculated more accurately. The preload inspection method for a wheel bearing device provided with an outer member having an outside raceway surface, an inner member having an inside raceway surface, and rolling bodies, is provided with: a power calculation step in which the outer member or the inner member is rotated in a relative manner and the power is calculated; a preload value calculation step in which a preload value is calculated on the basis of the power calculated in the power calculation step; and a pass/fail I determination step is made on the basis of whether the preload value calculated in the preload value calculation step is within a permissible range.

Provided is a hub unit bearing wherein a cover can be firmly fitted with an outer ring member, and it is difficult for foreign matter to enter inside through a water drainage hole formed in the cover. The cover that covers the inside end section in the axial direction of the hub unit bearing includes a disk section, a small-diameter cylindrical section bent in the axial direction from the outer perimeter edge section of the disk section and a large-diameter cylindrical section. A cut and raised section that is cut and raised toward the inside in the radial direction is formed in the small-diameter cylindrical section, and a water drainage hole that passes through from inside to outside the cover is provided in the portion that is cut and separated from the small-diameter cylindrical section.

A wheel bearing apparatus has a double row angular contact ball bearing. A height of a shoulder of a shoulder portion (18) of an outer member (12) with respect to a ball diameter of a double ball (14) row is set in a range of 0.35 to 0.50 mm. A corner (19) of the shoulder portion (18) has a relief surface (19a) and a chamfered portion (19b). The relief surface is on a straight line that is on a tangent line of an outer raceway surface (12a). The chamfered portion (19b) is round in a circular arc with a predetermined radius of curvature r. The corner (19) is formed simultaneously by a formed grinding wheel forming the double row outer raceway surface (12a). The corner is formed smoothly continuous from each outer raceway surface (12a). A length in the radial direction of the relief surface (19a) is set greater than or equal to 0.2 mm.

Provided is a bearing device for a vehicle wheel that is suitable in being able to prevent impairment in assemblability of the bearing device for a vehicle wheel to a knuckle without cost increase. A bearing device for a vehicle wheel (1) is provided with an inner member and an outer ring (2) which is an outer member having a vehicle-body-mounting flange part (2d), wherein the outer ring (2) has a pilot part (2e) disposed inward of the vehicle-body-mounting flange part (2d), and the pilot part (2e) has a fitting portion (2f) configured to be fitted to a knuckle (10) and a guiding portion (2g) having a diameter which gradually decreases inward from the inner-side end of the fitting portion (2f).

A wheel hub bearing for motor vehicles providing a hub and a bearing unit in turn comprising a radially outer ring, at least one radially inner ring, at least one crown of rolling bodies between the radially outer ring and the radially inner ring. The hub has a radial stiffening. The radial stiffening of the hub has a misalignment respect to a seat. Accordingly, a distance between a centerline axis of the seat of the radially inner ring on the hub and a center line of the radial stiffening, less than or equal to 25% of a length of the seat.

An in-wheel motor drive device (10) includes a wheel hub bearing unit (11) having an outer ring (13), an inner ring (12) protruding from the outer ring to one side in an axial (O) direction, rolling elements (14) between the outer ring and the inner ring, and a fixing bolt (15) for fixing the outer ring to a non-rotary member (102); and a brake disk (55) having a connecting portion (58) configured to connect with one end of the inner ring, a cylindrical portion (57) extending from the connecting portion to the other side in the axial direction and disposed coaxially to the inner ring, and at least a part of the fixing bolt is received in an internal space of the cylindrical portion.

A hub assembly includes an inner rotatable hub having inboard and outboard axial ends, a radial flange extending outwardly from the outboard axial end and connectable with the wheel, an inner circumferential surface, and an opposing outer circumferential surface providing inboard and outboard inner races. An outer hub is disposed about the inner hub, connectable with the chassis and has inboard and outboard axial ends, an outer circumferential surface and an inner circumferential surface. The inner surface provides inboard and outboard outer races and a central surface section extending between the two outer races. First and second sets of rolling elements are disposed between the inner and outer races. One or more sensors are each disposed on the central surface section of the outer hub and are each configured to sense strain within the outer hub generated by the rolling elements.

A bearing unit for a wheel hub assembly for motor vehicles, the bearing unit having an axis of rotation (X) and having two radially outer raceways, two radially inner raceways, two rows of rolling bodies, the bearing unit having tribological parameters whose values affect the magnitude of the frictional forces between the respective raceways and rolling bodies of the rows of rolling bodies, wherein at least one value of a tribological parameter is minimized or maximized to reduce the magnitude of the frictional forces as a function of the relative position along the axis (X) of a line of action (W) of loads acting on the bearing unit and of the plane of axial symmetry (Z).

A bearing device for a wheel, which has improved axial assembly accuracy of a sealing member by reducing the amount of springback. The bearing device for a wheel comprises an inner sealing member that blocks an inner opening end of an annular space formed by an outer ring and an inner ring. A sealing ring of the inner sealing member has a core metal fitting in the outer ring and an elastic member joined to the core metal. The elastic member has: a pressing part that is pressed inward in the axial direction when the sealing ring is press-fitted into the outer ring; and a non-pressing part that is not pressed inward in the axial direction when the sealing ring is press-fitted into the outer ring, wherein the axial thickness of the pressing part is thinner than the axial thickness of the non-pressing part.

A hub assembly includes an inner rotatable hub having inboard and outboard axial ends, a radial flange extending outwardly from the outboard axial end and connectable with the wheel, an inner circumferential surface, and an opposing outer circumferential surface providing inboard and outboard inner races. An outer hub is disposed about the inner hub, connectable with the chassis and has inboard and outboard axial ends, an outer circumferential surface and an inner circumferential surface. The inner surface provides inboard and outboard outer races and a central surface section extending between the two outer races. First and second sets of rolling elements are disposed between the inner and outer races. One or more sensors are each disposed on the central surface section of the outer hub and are each configured to sense strain within the outer hub generated by the rolling elements.