Each of column portions has a first branch portion and a second branch portion bifurcated in the circumferential direction at one end portion in the axial direction, and a grease storage groove between the first and second branch portions, a tip-end portion of the first branch portion of one column portion and a tip-end portion of the second branch portion of an adjacent column portion are connected in the circumferential direction, and a tip-end portion of the second branch portion of the one column portion and a tip-end portion of the first branch portion of another adjacent column portion are connected in the circumferential direction.

A bearing apparatus for wheels includes an outer ring, a hub shaft, rolling elements, a seal attached to a vehicle-outer-side part of the outer ring, a rotating slinger attached to the vehicle-outer-side part of the hub shaft and contacted by the seal, and a fixed slinger attached to a vehicle-outer-side outer periphery of the outer ring and contacted by the seal. An outer peripheral surface of the outer ring has a non-plated surface portion provided at a vehicle-outer-side end of the outer ring and a plated surface portion that is continuous with the non-plated surface portion. The fixed slinger has an inner cylindrical portion externally fitted over and attached to the non-plated surface portion. The seal has an inner lip that contacts the rotating slinger and an outer lip that contacts the inner cylindrical portion.

A bearing apparatus for wheels includes an outer ring, a hub shaft having a flange portion for Wheel attachment on a vehicle outer side, rolling elements provided between the outer ring and the hub shaft, a seal attached to the vehicle-outer-side part of the outer ring, and a slinger that is attached to the vehicle-outer-side part of the hub shaft and contacted by the seal An outer peripheral surface of the outer ring has a non-plated surface portion provided at a vehicle-outer-side end and a plated surface portion continuous with the non-plated surface portion. The slinger has a slinger main body portion that is contacted by the seal and a cylindrical facing portion that faces the non-plated surface portion to form a labyrinth clearance.

A rotary shaft device (3) includes a shaft body (20) rotatably supported by angular bearings (35, 36), and a support body (40) configured to rotatably support the shaft body (20) via the angular bearings (35, 36). A ball rolling groove (21) having a Gothic arch shape in which rolling elements (39) of the angular bearings (35, 36) roll is formed in an outer circumferential surface of the shaft body (20).

A rotary shaft locking device includes a rotary shaft, a first angular contact ball bearing, a support, and an actuator. The rotary shaft is rotatable about a first axis and has a first contact surface. The first angular contact ball bearing includes an inner ring connected to the rotary shaft, an outer ring, and a plurality of balls disposed between the inner ring and the outer ring. The support has a second contact surface and rotatably supports the rotary shaft via the first angular contact ball bearing. The actuator is configured to move the rotary shaft and the inner ring with respect to the support and the outer ring in a first direction parallel to the first axis so that the first contact surface contacts the second contact surface to prohibit the rotary shaft from rotating and so that precompression that acts on the plurality of balls is reduced.

A method for adjusting an axial preload in a bearing assembly that has two rolling-element bearings that are axially pressable against each other, each of the two rolling-element bearings including at least one bearing outer ring and at least one bearing inner ring and at least one row of rolling elements disposed between the at least one bearing outer ring and at least one bearing inner ring. The method includes a) driving the bearing assembly by rotating one of the bearing outer ring and the bearing inner ring while holding other bearing ring fixed and measuring the rotational speed of the circulation of the rolling elements about the bearing assembly axis or of a bearing cage about the stationary bearing ring, and b) changing the axial preload in the bearing assembly until a desired rotational speed has been obtained.

The invention concerns a large-size rolling bearing which is in the form of a multi-row ball-bearing rotary joint for carrying axial loads, radial loads and tilting moments. The large-size rolling bearing has an outer race, an inner race, a first ball row and a second ball row. The first ball row and the second ball row are respectively arranged in axially mutually spaced relationship in a four-point bearing configuration, associated with the first ball row are four raceway portions and associated with the second ball row are four raceway portions. The invention concerns in particular a large-size rolling bearing in which a surface of a respective raceway portion provided in the inner race is larger than the surface of the respectively adjacent raceway portion provided in the inner race and equal to the surface of the respectively diametrally oppositely disposed raceway portion provided in the outer race.

The present invention describes a wind turbine comprising a hub, at least one blade and at least one pitch bearing to connect the at least one blade to the hub, the at least one pitch bearing comprising at least an inner ring and an outer ring, and at least a rolling race, wherein the wind turbine further comprises at least a tensioning system configured to exert a radial compression force to at least a part of the outer ring of the at least one pitch bearing, thus increasing the resultant stiffness of the at least one pitch bearing.

A double row angular contact ball bearing includes an outer ring and an inner ring having two axially interconnected ring elements. Two outer raceways are provided on the outer ring, and an inner raceway is provided on each ring element, balls running on the outer and inner raceways in two arrows. A ring section of a ring element protrudes axially beyond the outer ring, and a measuring body is provided on the outer cylindrical lateral surface of the ring section. A measuring device with a measuring means which detects the measuring body is provided on the outer ring, said measuring means being positioned radially adjacently to the measuring body and at a distance thereto across a measuring gap.

A bearing assembly is for supporting a shaft in a housing, preferably a rotor shaft of a centrifugal compressor. The bearing assembly includes at least a first bearing pair including a first rolling bearing and a second rolling bearing arranged back to back, each one of the first and second rolling bearings including an inner ring attached to the shaft, an outer ring and a plurality of rolling elements disposed between the inner ring and the outer ring. A radial gap is provided between the outer ring of the first rolling bearing and the housing and the outer ring of the second rolling bearing is in contact with the housing. Preferably, a fixing element restricts axial movement of the outer ring of the first rolling bearing with respect to the housing.