A main bearing assembly of a wind turbine includes at least one main bearing with a rotation axis and at least one bearing row in which a rotor shaft of the wind turbine is mounted. The main bearing assembly has at least one stationary bearing ring, a circulating bearing ring and rolling elements. A method of extending the service life or servicing the main bearing assembly includes rotating the stationary bearing ring about the rotation axis of the main bearing assembly. Alternatively, only a new stationary bearing ring, preferably with at least two bearing ring segments is installed instead of a damaged outer ring, in particular without further important bearing components such as the inner ring being exchanged.

A hover-capable aircraft is described that comprises a drive unit, a rotor and a transmission interposed between the drive unit and the rotor; the transmission comprises a gear; the gear, in turn, comprises a main body rotatable about a first axis and a plurality of first teeth projecting in a cantilever fashion from the main body; the gear comprises a first pair of first rings axially opposite to each other and cooperating with the gear so as to exert a radial force on the gear.

To provide a rolling bearing having a hard film on an inner ring raceway surface and an outer ring raceway surface of the rolling bearing that improves peeling resistance of the hard film, shows the original property of the hard film, and suppresses the attackability to a mating material. A rolling bearing 1 has an inner ring 2 having an inner ring raceway surface 2a on an outer circumference, an outer ring 3 having an outer ring raceway surface 3a on an inner circumference, and rolling elements 4 that roll between the inner ring raceway surface 2a and the outer ring raceway surface 3a. A hard film 8 includes a foundation layer formed directly on the inner ring raceway surface 2a or the outer ring raceway surface 3a and mainly formed of Cr and WC, a mixed layer having a gradient composition formed on the foundation layer and mainly formed of WC and DLC, and a surface layer formed on the mixed layer and mainly formed of DLC. In a roughness curve of a surface on which the foundation layer is formed, the arithmetical mean roughness Ra is 0.3 μm or less and the root mean square gradient RΔq is 0.05 or less.

Disclosed is a sealed bearing arrangement that provides at least a bearing with an outer ring and an inner ring, which are rotatable to each other and form a rolling chamber between each other, in which a set of rolling elements. A lubricant is encompassed in the rolling chamber and the rolling chamber is sealed off from an environment by at least one sealing element. The inner ring, the outer ring and/or the sealing element includes at least one opening for providing a fluid passage through the sealing element. The bearing is arranged in a housing that is adapted to seal off the bearing from an outside environment. A lubricant is encompassed inside the housing. The housing including the at least one opening for providing a fluid passage from the inside of the housing to the outside. The opening is fluid tightly connected to an oxygen removing element and/or to a gas tank, which provides an oxygen poor to free fluid flow to the rolling chamber.

A mobile milling machine includes a cutting rotor disposed along a rotor drum delineating a drum rotation axis and accommodated in a rotor chamber delineated by chamber enclosure. To rotatably support the rotor drum with respect to the chamber enclosure, the rotor drum can include a bearing end and the chamber enclosure can include a bearing bore that are adapted to form a drum bearing assembly. The drum bearing assembly may include a bearing hub and a bushing configured to make a sliding frictional contact along complementary taper surfaces. The floating bushing may be floatingly retained in a chamber door of the chamber enclosure.

A rolling bearing has an inner and an outer bearing ring. Each bearing ring has an inner and an outer shell surface. The roller bearing has rolling elements, which roll on raceways provided on the respective shell surfaces of the bearing rings, and a sealing disc connected to one of the bearing rings and operatively connected in a sealing manner to the other bearing ring. To connect the sealing disc to the bearing ring, one of the shell surfaces of the one bearing ring includes a first connecting means and the sealing disc includes a second connecting means. The first connecting means provide a rotating engagement in which the second connecting means engage in a connected state of the bearing ring and the sealing disc.

Example aspects of a rotating machine, a method for pre-loading a rotating machine, and a method for using a rotating machine are disclosed. The rotating machine can comprise a stator; a rotor, wherein one of the stator and the rotor comprises a mounting flange formed monolithically therewith; a bearing directly mounted to the mounting flange; and the other of the stator and the rotor directly mounted to the bearing.

A bearing unit having a stationary radially outer ring, a radially inner ring rotatable about a central rotation axis (X) of the bearing unit is provided with at least one raceway and, in an end portion thereof, with at least two circular sector segments, at least one row of rolling elements interposed between the radially outer ring and the radially inner ring, and a concentric collar for clamping the radially inner ring on a rotating shaft, where an induction-hardening heat treatment is applied to a portion of the radially inner ring that overlaps with at least a portion of the at least one raceway.

A drive train for an electric machine is provided. The drive train includes a shaft. The shaft has a front end and a rear end and which is supported in a housing via a front bearing and a rear bearing, wherein the front bearing including a front bearing outer ring and a front bearing inner ring, and the rear bearing including a rear bearing outer ring and a rear bearing inner ring). The drive train includes a first cover mounted to the housing and being configured to seal a rear side of the front bearing, wherein the first cover is mounted to the housing by an auxiliary support which connects the first cover to the housing, a second cover mounted to the housing and being configured to seal a front side of the rear bearing, a third cover mounted to the housing and being configured to seal the rear bearing.

A rolling bearing assembly includes an inner ring supported by a shaft or formed by a surface of the shaft, an outer ring supported in a housing or formed by a surface of the housing, a plurality of rolling elements disposed between the inner ring and the outer ring, and at least one distance sensor configured to measure a distance between the shaft and the housing in order to detect wear of the rolling bearing.