A bearing cage for large rolling-element bearings includes a first side part and a second side part and a plurality of bridge elements connecting the first and second side parts to form a plurality of cage pockets each configured to receive a rolling element. The at least one bridge element and/or the first side part and/or the second side part includes at least one opening, and an insert element is mounted in each of the at least one opening and configured to contact the rolling element.

A bearing device is provided which achieves both creep resistance and electrolytic corrosion resistance. At least one of the radially inner surface of the inner ring and the radially outer surface of the outer ring is covered with a coating layer. The coating layer is a coating layer composite composed of a plurality of layers. Of the plurality of layers, the surface layer is composed of an anti-creep film having lubricity, and at least one layer other than the surface layer is composed of an insulating film having insulating properties.

To provide a rolling bearing retainer formed as a metal retainer and being capable of suppressing wear of a guide surface of a pocket that retains a ball served as a rolling element even in a case in which a lubrication function by a lubricant is deteriorated. A rolling bearing 1 is provided with an inner ring 2, an outer ring 3, a ball 4 interposed between the inner ring 2 and the outer ring 3, and a retainer 5 that retains the ball 4. The retainer 5 is formed as a metal retainer including pockets 6, each of which retains the ball 4, formed at positions in a circumferential direction and including a resin coating film formed on at least an inner surface of each of the pockets 6 served as a rolling element guide surface. The resin coating film 7 is formed of a resin composition including an aromatic polyether ketone based resin as a matrix resin and including a solid lubricant.

A rolling-element bearing cage having a central axis of rotation includes a first cage ring having an axial extension and at least one snap arm disposed directly on the extension, and a second cage ring having an attachment region to which the at least one snap arm is snapped. The attachment region is located at a first distance from the central axis of rotation. A portion of each of the at least one each snap arm of the first cage ring is located at a second distance from the central axis of rotation, the second distance being less than the first distance.

Provided is a retainer (7), including a pair of annular members (8, 8), the pair of annular members (8, 8) being coupled to each other so that semispherical bulging portions (9, 9) which are opposed to each other form pockets (11) configured to retain balls (6). The pockets (11) each include a ball-opposed surface (12) having a ball non-contact portion (14) that is recessed toward a side opposite to the ball side. The ball non-contact portion (14) is formed outside a predetermined region (A) of the ball-opposed surface (12), which includes an intersection (P) of a pitch circle (PCD) of the balls (6) and a straight line (L) extending in a radial direction through a central portion of the ball-opposed surface (12) in a circumferential direction, and has an end portion on a radially outer side which is opened in a radially outer surface (8a) of the annular member (8).

Half-cage for forming cages (10) for ball bearings, in which the half-cages (11, 21) comprise semi-spherical recesses (12, 22) arranged at predefined intervals along a circumference. The semi-spherical recesses are spaced out from each other by means of respective planar portions (14, 24), are arranged along the circumference, and comprise at least one rib (31, 41) having a certain width and extending along the circumference over at least the whole surface of said recesses.

A rolling-element bearing cage having a central axis of rotation includes a first cage ring having an axial extension and at least one snap arm disposed directly on the extension, and a second cage ring having an attachment region to which the at least one snap arm is snapped. The attachment region is located at a first distance from the central axis of rotation. A portion of each of the at least one each snap arm of the first cage ring is located at a second distance from the central axis of rotation, the second distance being less than the first distance.

A bearing cage for large rolling-element bearings includes a first side part and a second side part and a plurality of bridge elements connecting the first and second side parts to form a plurality of cage pockets each configured to receive a rolling element. The at least one bridge element and/or the first side part and/or the second side part includes at least one opening, and an insert element is mounted in each of the at least one opening and configured to contact the rolling element.