Abstract: A roller bearing includes: inner and outer rings; rollers interposed between raceway surfaces of the inner and outer rings and having a roller outer circumferential surface; a cage retaining the rollers; and a DLC film on the roller outer circumferential surface. The DLC film includes a superficial layer having cavities provided therein to hold a lubricating agent. The rollers have a ratio of surface area occupied by the cavities of 40% or less, and the cavities have a size of 10 to 100 ?m when viewed in a plan view thereof. The DLC film can have a multilayered structure in which the superficial layer is layered on an additional layer, and the cavities can include a void of soft DLC present in the superficial layer and having a film hardness lower than that of the additional layer.

Abstract: Provided is a roller bearing which includes rollers (4, 5) interposed between raceway surfaces of inner and outer rings (2, 3) and having a roller outer circumferential surface, and a DLC film on the roller outer circumferential surface. The DLC film includes a metal layer, an intermediate layer containing the metal and DLC, and a superficial layer containing DLC, in the stated order starting from a side adjacent to a substrate of the rollers (4, 5). The intermediate layer has a bilayered structure of a top layer and a bottom layer. The top layer is a DLC-enriched layer having a greater content of DLC than the bottom layer. The bottom layer is a metal-enriched layer having a greater content of the metal than the top layer. The metal-enriched layer has a layer thickness of between at least 100 nm and no more than 300 nm.

Abstract: Provided is a self-aligning roller bearing for supporting a main shaft of a wind power generator, the self-aligning roller bearing including an inner ring, an outer ring, two rows of rollers, and retainers. Each of the rollers has an outer peripheral surface formed with a DLC coating having a multilayer structure. The DLC coating has a film thickness of 2.0 ?m or larger. A base material of each of the rollers has an external surface having a surface roughness of Ra?0.3 and R?q?0.05. The DLC coating having the multilayer structure includes layers having stepwisely increasing film hardnesses such that a layer situated closer to outside has a higher hardness.

Abstract: Provided is a double-row self-aligning roller bearing including: an inner ring; an outer ring having a spherical raceway surface; and rollers arranged in two rows and interposed between the inner ring and the outer ring, wherein a ratio of a contact angle ?1 in one row to a contact angle ?2 in the other row falls within a range of 0.25??1/?2?0.5, and a ratio of distance B1 in a bearing width direction from an end face of the bearing on a side of the one of the rows to an intersection of two lines of action defining the contact angles of the two rows, relative to a distance B2 in the bearing width direction from an end face of the bearing on a side of the other of the rows to the intersection falls within a range of 0.5?B1/B2?0.6.

Abstract: Provided is a self-aligning roller bearing for supporting a main shaft of a wind power generator, the self-aligning roller bearing including an inner ring, an outer ring, two rows of rollers, and retainers. Each of the rollers has an outer peripheral surface formed with a DLC coating having a multilayer structure. The DLC coating has a film thickness of 2.0 ?m or larger. A base material of each of the rollers has an external surface having a surface roughness of Ra?0.3 and R?q?0.05. The DLC coating having the multilayer structure includes layers having stepwisely increasing film hardnesses such that a layer situated closer to outside has a higher hardness.

Abstract: The double-row self-aligning roller bearing includes an outer ring having a spherical raceway surface, and each of rollers in two rows has an outer peripheral surface whose cross-sectional shape corresponds to the raceway surface of the outer ring. The rollers in the two rows have different lengths from each other, and the length of the longer rollers is equal to or greater than 36% of a bearing width. A ratio of a contact angle of the shorter rollers relative to a contact angle of the longer rollers is within a range of 1:4 to 1:2. The contact angle of the shorter rollers has a range of 3° to 5°, and the contact angle of the longer rollers has a range of 11° to 14°.

Abstract: Provided is a double-row self-aligning roller bearing including: an inner ring; an outer ring having a spherical raceway surface; and rollers arranged in two rows and interposed between the inner ring and the outer ring, wherein a ratio of a contact angle ?1 in one row to a contact angle ?2 in the other row falls within a range of 0.25??1/?2?0.5, and a ratio of distance B1 in a bearing width direction from an end face of the bearing on a side of the one of the rows to an intersection of two lines of action defining the contact angles of the two rows, relative to a distance B2 in the bearing width direction from an end face of the bearing on a side of the other of the rows to the intersection falls within a range of 0.5?B1/B2?0.6.

Abstract: A double-row self-aligning roller bearing has rollers interposed, in two rows aligned in a bearing width direction, between an inner ring and an outer ring. The outer ring has a spherical raceway surface. Each of the rollers has an outer circumferential surface having a cross-sectional shape that matches the raceway surface of the outer ring. Either or both of shapes and contact angles of the rollers are different from each other. An attachment hole to which a protrusion prevention jig is attachable is provided in an end surface of at least either one of the inner ring and the outer ring. The protrusion prevention jig prevents protrusion of the end surface of the inner ring in the bearing width direction with respect to the end surface of the outer ring.

Abstract: A rolling bearing includes an inner ring, an outer ring, and rolling elements interposed between the inner ring and the outer ring. A surface layer portion, beneath a raceway surface (10a), of a base material of a raceway ring (10) which is the inner ring or the outer ring, is a wear-resistant layer (13) which has a higher hardness than a residual portion (12), beneath the surface layer portion, of the base material, and includes a minute-recess-and-projection surface. An oxide film (14) is provided which has such a film thickness (t) as to fill recesses of the minute-recess-and-projection surface of the wear-resistant layer (13), and includes recesses and projections existing along the minute-recess-and-projection surface, and the oxide film (14) coats the surface of the wear-resistant layer (13). The oxide film (14) is made from a material more fragile than the wear-resistant layer (13) of the base material.

Abstract: A double-row self-aligning roller bearing has rollers interposed, in two rows aligned in a bearing width direction, between an inner ring and an outer ring. The outer ring has a spherical raceway surface. Each of the rollers has an outer circumferential surface having a cross-sectional shape that matches the raceway surface of the outer ring. The rollers have lengths equal to each other and maximum diameters equal to each other, and have different distances from centers of the roller lengths to positions at which the maximum diameters are obtained.

Abstract: The double-row self-aligning roller bearing includes an outer ring having a spherical raceway surface, and each of rollers in two rows has an outer peripheral surface whose cross-sectional shape corresponds to the raceway surface of the outer ring. The rollers in the two rows have different lengths from each other, and the length of the longer rollers is equal to or greater than 36% of a bearing width. A ratio of a contact angle of the shorter rollers relative to a contact angle of the longer rollers is within a range of 1:4 to 1:2. The contact angle of the shorter rollers has a range of 3° to 5°, and the contact angle of the longer rollers has a range of 11° to 14°.

Abstract: A double-row self-aligning roller bearing, which is suitable for receiving an axial load and a radial load, and loads having different magnitudes acting on rollers in two rows, and achieves sufficient load capacity for the rollers that receive axial load within the constraint of dimensional standards, is provided. The double-row self-aligning roller bearing includes inner and outer rings; and rollers in two rows arranged in a bearing width direction interposed between the inner and outer rings and having lengths different from each other. The roller has an outer peripheral surface of a cross-sectional shape along a raceway surface of the outer ring having a spherical shape. Length of the longer rollers is equal to or greater than 39% of the bearing width. A ratio of contact angle of the shorter rollers and contact angle of the longer rollers is within a range of 1:4 to 1:2.

Abstract: A double-row self-aligning roller bearing has rollers interposed, in two rows aligned in a bearing width direction, between an inner ring and an outer ring. The outer ring has a spherical raceway surface. Each of the rollers has an outer circumferential surface having a cross-sectional shape that matches the raceway surface of the outer ring. The rollers have lengths equal to each other and maximum diameters equal to each other, and have different distances from centers of the roller lengths to positions at which the maximum diameters are obtained.

Abstract: A double-row self-aligning roller bearing has rollers interposed, in two rows aligned in a bearing width direction, between an inner ring and an outer ring. The outer ring has a spherical raceway surface. Each of the rollers has an outer circumferential surface having a cross-sectional shape that matches the raceway surface of the outer ring. Either or both of shapes and contact angles of the rollers are different from each other. An attachment hole to which a protrusion prevention jig is attachable is provided in an end surface of at least either one of the inner ring and the outer ring. The protrusion prevention jig prevents protrusion of the end surface of the inner ring in the bearing width direction with respect to the end surface of the outer ring.

Abstract: A rolling bearing includes an inner ring, an outer ring, and rolling elements interposed between the inner ring and the outer ring. A surface layer portion, beneath a raceway surface (10a), of a base material of a raceway ring (10) which is the inner ring or the outer ring, is a wear-resistant layer (13) which has a higher hardness than a residual portion (12), beneath the surface layer portion, of the base material, and includes a minute-recess-and-projection surface. An oxide film (14) is provided which has such a film thickness (t) as to fill recesses of the minute-recess-and-projection surface of the wear-resistant layer (13), and includes recesses and projections existing along the minute-recess-and-projection surface, and the oxide film (14) coats the surface of the wear-resistant layer (13). The oxide film (14) is made from a material more fragile than the wear-resistant layer (13) of the base material.

Abstract: A double-row self-aligning roller bearing, which is suitable for receiving an axial load and a radial load, and loads having different magnitudes acting on rollers in two rows, and achieves sufficient load capacity for the rollers that receive axial load within the constraint of dimensional standards, is provided. The double-row self-aligning roller bearing includes inner and outer rings; and rollers in two rows arranged in a bearing width direction interposed between the inner and outer rings and having lengths different from each other. The roller has an outer peripheral surface of a cross-sectional shape along a raceway surface of the outer ring having a spherical shape. Length of the longer rollers is equal to or greater than 39% of the bearing width. A ratio of contact angle of the shorter rollers and contact angle of the longer rollers is within a range of 1:4 to 1:2.

Abstract: A double-row self-aligning roller bearing includes an inner ring, an outer ring having a spherical raceway surface, and rollers in a left row and rollers in a right row interposed between the inner ring and the outer ring, the rollers in the left row and the rollers in the right row each having an outer peripheral surface having a cross-sectional shape along the raceway surface of the outer ring. The length of each roller in the left row and the length of each roller in the right row are different from each other, and the number of the rollers in the left row and the number of the rollers in the right row are different from each other.