To provide a hub bearing that is capable of reducing a delay in a response of the hub bearing and improving a steering stability of a vehicle. A hub bearing 1 includes an outer ring 2 serving as a stationary side raceway ring, a hub wheel 3 and an inner ring 5 serving as a rotatable side raceway ring, balls 4 serving as a plurality of rolling elements disposed between a raceway surface of the stationary side raceway ring and a raceway surface of the rotatable side raceway ring, and grease that lubricates a rolling contact part between each of the raceway surfaces and the rolling elements. The surface roughness of at least one raceway surface selected from the raceway surface of the stationary side raceway ring and the raceway surface of the rotatable side raceway ring in the rolling contact part is 0.03 μmRa or less. Further, the grease has a traction coefficient in the rolling contact part of 0.04 or less at 40° C. when a vehicle speed is 20 km/h or more.

To provide a hub bearing that is capable of reducing a delay in a response of the hub bearing and improving a steering stability of a vehicle. A hub bearing 1 includes an outer ring 2 serving as a stationary side raceway ring, a hub wheel 3 and an inner ring 5 serving as a rotatable side raceway ring, balls 4 serving as a plurality of rolling elements disposed between a raceway surface of the stationary side raceway ring and a raceway surface of the rotatable side raceway ring, and grease that lubricates a rolling contact part between each of the raceway surfaces and the rolling elements. The surface roughness of at least one raceway surface selected from the raceway surface of the stationary side raceway ring and the raceway surface of the rotatable side raceway ring in the rolling contact part is 0.03 μmRa or less. Further, the grease has a traction coefficient in the rolling contact part of 0.04 or less at 40° C. when a vehicle speed is 20 km/h or more.

A sealing device for sealing off external contaminants from a bearing unit between a stationary radially outer ring and a rotatable radially inner ring, the sealing device including a first, metallic and rotatable annular screen having a first mounting area for assembly with interference on the radially inner ring, a second, metallic and stationary annular screen having a second mounting area for assembly with interference on the radially outer ring, an annular sealing element made of elastomeric material, integrally supported by the second annular screen, and equipped with at least one contacting annular sealing lip projecting axially and radially from the second screen towards the first screen, and a non-contacting annular lip extending axially and facing a first flange portion of the first annular screen.

A wheel bearing device (1) including: an outer member (2) on the inner periphery of which an outer-side rolling surface (2c/2d) is formed; an inner member (3) on the outer periphery of which an inner-side rolling surface (3c/3d) is formed; and a plurality of rolling bodies (41) interposed between the rolling surfaces (2c/2d/3c/3d) of the outer member (2) and the inner member (3). The wheel bearing device having a spline hole (3b) formed in a through hole (3h) of the inner member (3). The spline hole includes a guide groove (3G) formed on an inner circumferential surface thereof. A guide plate (8G) of a finishing broach (8) passes through the guide groove in the inner periphery of the spline hole (3b).

A wheel bearing device (1) including: an outer member (2) on the inner periphery of which an outer-side rolling surface (2c/2d) is formed; an inner member (3) on the outer periphery of which an inner-side rolling surface (3c/3d) is formed; and a plurality of rolling bodies (41) interposed between the rolling surfaces (2c/2d/3c/3d) of the outer member (2) and the inner member (3). The wheel bearing device having a spline hole (3b) formed in a through hole (3h) of the inner member (3). The spline hole includes a guide groove (3G) formed on an inner circumferential surface thereof. A guide plate (8G) of a finishing broach (8) passes through the guide groove in the inner periphery of the spline hole (3b).

A steering system includes a steered shaft, a ball screw nut, balls, a housing, a rolling bearing, and a snap ring configured to prevent the rolling bearing from detaching from the ball screw nut. The rolling bearing includes double-row rolling element arrays, an outer ring, a first inner ring, and a second inner ring. The ball screw nut has a receiving portion. The snap ring contacts a side face of the second inner ring to push the second inner ring toward the receiving portion via the first inner ring. A resistance force received from the second outer peripheral fitting surface when the second inner ring moves in the axial direction in a state in which detachment of the rolling bearing is not prevented by the snap ring is smaller than a pushing force with which the snap ring pushes the second inner ring.

A gantry assembly includes a rotor, a stator and a bearing for coupling the rotor and the stator. The bearing includes an inner ring connected with the rotor or stator, an outer ring connected with the other one of the rotor and the stator and rolling elements between the two rings. The ring connected with the stator, preferably the outer ring, includes one or more damping washers disposed between the ring and the stator, each washer being disposed about one threaded fastener connecting the ring with the stator. Also, one or more damping cylinders are each disposed within a mounting hole of the ring connected with the stator and about a threaded fastener disposed within the hole. The bearing ring connected with the rotor may also include damping washers between the ring and the rotor or/and damping cylinders disposed within mounting holes receiving fasteners connecting the ring with the rotor.

A gantry assembly includes a rotor, a stator and a bearing for coupling the rotor and the stator. The bearing includes an inner ring connected with the rotor or stator, an outer ring connected with the other one of the rotor and the stator and rolling elements between the two rings. The ring connected with the stator, preferably the outer ring, includes one or more damping washers disposed between the ring and the stator, each washer being disposed about one threaded fastener connecting the ring with the stator. Also, one or more damping cylinders are each disposed within a mounting hole of the ring connected with the stator and about a threaded fastener disposed within the hole. The bearing ring connected with the rotor may also include damping washers between the ring and the rotor or/and damping cylinders disposed within mounting holes receiving fasteners connecting the ring with the rotor.

A hub bearing assembly includes a housing with a vertical bore, a bearing outer ring disposed within the bore and coupled with the housing and a bearing inner ring disposed within the bearing outer ring and having a central bore configured to receive a portion of the shaft. A set of rolling elements are disposed between the bearing outer and inner rings. An upper seal is disposed within the housing bore externally of the outer ring and includes an annular elastomeric seal body and a garter spring biasing a seal lip radially inwardly. A lower seal is disposed between the bearing outer and inner rings. Either the bearing inner ring is sized such that upper seal is disposed about the bearing inner ring or the hub bearing assembly further comprises an annular spacer disposed within the upper seal and adjacent to the upper axial end of the bearing inner ring.

The disclosure relates to a head bearing assembly for a dental or surgical handpiece, comprising an outer sleeve, in which at least four radial bearings are arranged, which enclose an axis of rotation and each have their own bearing outer ring or a common bearing outer rings, wherein the bearing outer rings are surrounded radially on the outside by the outer sleeve in the circumferential direction about the axis of rotation, and each radial bearing has at least one or exactly one rolling element row with rolling elements which are arranged one behind the other in the circumferential direction and rolling in the respective bearing outer ring.

The head bearing assembly according to the disclosure is characterized in that the at least four radial bearings have a common, integral bearing inner ring on which the rolling elements are arranged in rolling contact.