Rolling bearings are stacked with their center lines extending in a vertical direction. Each of the rolling bearings has an inner ring, an outer ring, a plurality of balls, and an annular cage. Each of the rolling bearings has a structure that induces, upon rotation, an action that causes lubricating oil to flow upward along the outer ring in the annular space. The cage has an annular portion provided adjacently below the balls to prevent air from moving to the outer ring side from the inner ring side.

A closure system between the cap and the stator in an electric rotating machine, wherein the stator (1) comprises at least one closure hole (1a) defining an inner wall (1b). The cap (2) comprises at least one contact portion (2a), the end of the contact portion comprising at least one through-hole (2c); the through-hole (2c) being substantially aligned with the closure hole (1a) when the end of the contact portion (2a) contacts the stator (1); and wherein a polymer (P) is injected through the through-hole (2c) in the inner wall (1b) of the closure hole. In the closing process of the present invention, the concentricity between the rolling bearing and the stator rotor accommodating bore is ensured by the fact that the geometry of the rolling bearing receiving portion (2e) allows the alignment to be made on the basis of the outer race (E) of the rolling bearing when it is already accommodated in the receiving portion (2e).

A cap for a rotating electric machine, the cap comprising at least a rolling bearing receiving portion (2) for receiving a rolling bearing (R) having an outer race (E), the rolling bearing receiving portion (2) comprising a radially resilient central portion (3) configured to exert pressure on the outer race (E) of the rolling bearing.

Rolling bearings are stacked with their center lines extending in a vertical direction. Each of the rolling bearings has an inner ring, an outer ring, a plurality of balls, and an annular cage. Each of the rolling bearings has a structure that induces, upon rotation, an action that causes lubricating oil to flow upward along the outer ring in the annular space. The cage has an annular portion provided adjacently below the balls to prevent air from moving to the outer ring side from the inner ring side.

A bearing arrangement of an electrical machine is provided that includes a drive shaft extending through a housing, the bearing arrangement including a front-end bearing arranged about a front end of the drive shaft, and a back-end bearing arranged about an opposite end of the drive shaft, wherein a bearing includes a plurality of bearing pads arranged in an annular space between the drive shaft and the housing, and wherein at least one bearing includes an uneven distribution of bearing pads about the drive shaft. Furthermore, a wind turbine including such a bearing arrangement is also provided.

The gas bearing pad includes a main body portion including a recess portion, a porous body fitted into the recess portion of the main body portion, and a bolt inserted into a bolt insertion hole provided in the porous body and fixing the porous body to the main body portion. A gas bearing is formed between the porous body and the base by blowing compressed gas from the main body portion through the porous body toward the base. A counterbore hole that accommodates a head portion of the bolt is provided in the bolt insertion hole. In the counterbore hole, a space is provided between a top surface that faces the guide surface in the head portion of the bolt and a bearing surface that faces the guide surface of the porous body.

The gas bearing pad includes a main body portion including a recess portion, a porous body fitted into the recess portion of the main body portion, and a bolt inserted into a bolt insertion hole provided in the porous body and fixing the porous body to the main body portion. A gas bearing is formed between the porous body and the base by blowing compressed gas from the main body portion through the porous body toward the base. A counterbore hole that accommodates a head portion of the bolt is provided in the bolt insertion hole. In the counterbore hole, a space is provided between a top surface that faces the guide surface in the head portion of the bolt and a bearing surface that faces the guide surface of the porous body.