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.

A roller bearing (10) defines a bearing axis (34) and a radial plane (52) oriented parallel with the bearing axis. The roller bearing (10) includes an inner ring (42) having an inner raceway (44) and an inner flange (46) extending from the inner raceway. The inner flange (46) includes an inner guide surface (48). The roller bearing (10) also includes a plurality of rollers (22) in rolling engagement with the inner raceway (44) about the bearing axis (34). Each roller (22) includes a first end surface (24a) in engagement with the inner guide surface (48) of the inner flange (46) as the plurality of rollers (22) move relative to the inner ring (42). The first end surfaces (24a) of each roller (22) define a curvature such that a ratio of a first principal effective curvature (Rx) radius in a plane perpendicular to the radial plane (52) and a second principal curvature radius (Ry) in the radial plane (52) is no less than 3.0.

A thrust bearing cage including an improved lubrication feature is disclosed. The thrust bearing cage includes a first rim and a second rim with a plurality of crossbars extending therebetween to define rolling element pockets. Each crossbar of the plurality of crossbars includes: a first radial flange extending from the first rim; a second radial flange extending from the second rim; and a medial radial flange connecting the first radial flange and the second radial flange. The medial radial flange is axially offset from the first radial flange and the second radial flange. At least one of the first radial flange, the medial radial flange, or the second radial flange includes a protrusion defining at least one ramped surface. The ramped surface creates a hydrodynamic effect, which guides the thrust bearing cage away from an adjacent surface, and ensures that a lubricated state is maintained.

A strut assembly for a bearing compartment of a gas turbine engine includes an inner case, an outer case, and a first plurality of struts. The inner case is disposed within the bearing compartment and includes a first axis. The outer case defines an exterior of the bearing compartment and includes a second axis disposed co-axially with the first axis. The inner and outer cases define a flowpath between the inner and outer cases. Each strut of the first plurality of struts extends between and is connected to the inner and outer cases. The first plurality of struts is configured to maintain concentric positioning between the inner and outer cases and to allow relative changes in size between the inner and outer cases without deforming the inner case.

A raceway surface (3a) of an outer ring (3) of a tapered roller bearing (1) includes a composite crowning surface. The composite crowning surface includes a center curve (3a1), which is formed at a center portion in a generating-line direction, and end portion curves (3a2 and 3a3), which are formed on both sides of the center curve (3a1) in the generating-line direction. The raceway surface (3a) of the outer ring (3) is entirely subjected to superfinishing. Each of a ratio (R.sub.2/R.sub.1) of a curvature radius (R.sub.2) of the end portion curve (3a2) to a curvature radius (R.sub.1) of the center curve (3a1) and a ratio (R.sub.3/R.sub.1) of a curvature radius (R.sub.3) of the end portion curve (3a3) to the curvature radius (R.sub.1) is set to 0.02 or more. Each of drop amounts of the end portion curves (3a2 and 3a3) is set to 0.07 mm or less.

A radial roller bearing can include an outer race having as a center axis a first axis extending in a first direction and an inner race having as the center axis the first axis. A group of rollers composed of a plurality of rollers arranged at intervals in the circumferential direction can be centered on the first axis between the outer raceway surface of the outer race and the inner raceway surface of the inner race and a cage can be provided for holding the group of rollers. A first regulating part can be provided for regulating the movement of the outer race to one side. A second regulating part can be provided for regulating the movement of the outer race to another side. The first regulating part and the second regulating part can be arranged at positions at which the distance between the first regulating part and the second regulating part is a prescribed distance longer than the outer race.

A raceway surface (3a) of an outer ring (3) of a tapered roller bearing (1) includes a composite crowning surface. The composite crowning surface includes a center curve (3a1), which is formed at a center portion in a generating-line direction, and end portion curves (3a2 and 3a3), which are formed on both sides of the center curve (3a1) in the generating-line direction. The raceway surface (3a) of the outer ring (3) is entirely subjected to superfinishing. Each of a ratio (R.sub.2/R.sub.1) of a curvature radius (R.sub.2) of the end portion curve (3a2) to a curvature radius (R.sub.1) of the center curve (3a1) and a ratio (R.sub.3/R.sub.1) of a curvature radius (R.sub.3) of the end portion curve (3a3) to the curvature radius (R.sub.1) is set to 0.02 or more. Each of drop amounts of the end portion curves (3a2 and 3a3) is set to 0.07 mm or less.

A method of reducing loads in a rotor assembly during an imbalance condition, a shape memory alloy recoupler device, and a hybrid bearing support system are provided. The hybrid bearing support system includes a shaft extension fixedly coupled to a rotatable member at a radially inner end of the shaft extension, a radially outer end of the shaft extension fixedly coupled to a rotatable race of a bearing supporting the rotatable member, and a recoupler device formed of a shape memory alloy (SMA) material coupled in parallel with at least a portion of the shaft extension between the radially inner end and the radially outer end.

A roller bearing (10) defines a bearing axis (34) and a radial plane (52) oriented parallel with the bearing axis. The roller bearing (10) includes an inner ring (42) having an inner raceway (44) and an inner flange (46) extending from the inner raceway. The inner flange (46) includes an inner guide surface (48). The roller bearing (10) also includes a plurality of rollers (22) in rolling engagement with the inner raceway (44) about the bearing axis (34). Each roller (22) includes a first end surface (24a) in engagement with the inner guide surface (48) of the inner flange (46) as the plurality of rollers (22) move relative to the inner ring (42). The first end surfaces (24a) of each roller (22) define a curvature such that a ratio of a first principal effective curvature (Rx) radius in a plane perpendicular to the radial plane (52) and a second principal curvature radius (Ry) in the radial plane (52) is no less than 3.0.

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.