Sealed bearing assembly
A sealed bearing assembly includes seal members each including a seal lip with multiple protrusions, and being arranged such that oil passages are defined between the seal lip and a seal sliding surface which is configured to slide circumferentially relative to the protrusions such that the oil passages communicate with a bearing internal space and an exterior of the bearing, and prevent passage of foreign objects having particle diameters larger than a predetermined value therethrough. The seal lip and the seal sliding surface are arranged such that, when the bearing rotates, lubricating oil in the oil passages is pulled into spaces between the seal lip and the seal sliding surface such that a fluid lubricating condition is created between the seal lip and the seal sliding surface, due to a wedge effect.
1. A sealed bearing assembly comprising:
a bearing defining a bearing interior space;
a seal member separating the bearing interior space from an exterior of the bearing, and including a seal lip;
a seal sliding surface configured to slide relative to the seal lip in a circumferential direction; and
a protrusion on one circumferential portion of the seal lip, the protrusion at least partially defining an oil passage extending between the seal sliding surface and the seal lip, and communicating with the bearing interior space and the exterior of the bearing;
wherein the protrusion is shaped and positioned such that a fluid lubricating condition can be created between the seal lip and the seal sliding surface, and
wherein the protrusion extends in a direction perpendicular to the circumferential direction, and has a rounded shape such that a distance between the protrusion and the seal sliding surface decreases from respective ends of the protrusion toward a center of the protrusion, with respect to a circumferential width of the protrusion.
2. The sealed bearing assembly of claim 1 , wherein the protrusion is one of a plurality of protrusions arranged at equal intervals over an entire circumference, and the oil passage is one of a plurality of oil passages defined by the plurality of protrusions.
3. The sealed bearing assembly of claim 2 , wherein the seal member includes a metal core, and a vulcanized rubber material attached to at least a radially inner portion of the metal core, and wherein the seal lip is formed of the vulcanized rubber material.
4. The sealed bearing assembly of claim 2 , wherein wedge-shaped gaps are defined between each of the plurality of protrusions and the seal sliding surface such that each of the wedge-shaped gaps is larger on a side of a corresponding one of the oil passages and smaller on a side of the corresponding one of the protrusions.
5. The sealed bearing assembly of claim 4 , wherein the seal member includes a metal core, and a vulcanized rubber material attached to at least a radially inner portion of the metal core, and wherein the seal lip is formed of the vulcanized rubber material.
6. The sealed bearing assembly of claim 1 , wherein the protrusion is formed with at least one circumferentially extending groove.
7. The sealed bearing assembly of claim 6 , wherein the seal member includes a metal core, and a vulcanized rubber material attached to at least a radially inner portion of the metal core, wherein the seal lip is formed of the vulcanized rubber material.
8. The sealed bearing assembly of claim 1 , wherein a wedge-shaped gap is defined between the protrusion and the seal sliding surface such that the wedge-shaped gap is larger on a side of the oil passage than on a side of the protrusion.
9. The sealed bearing assembly of claim 8 , wherein the seal member includes a metal core, and a vulcanized rubber material attached to at least a radially inner portion of the metal core, and wherein the seal lip is formed of the vulcanized rubber material.
10. The sealed bearing assembly of claim 1 , wherein the seal member includes a metal core, and a vulcanized rubber material attached to at least a radially inner portion of the metal core, and wherein the seal lip is formed of the vulcanized rubber material.
11. The sealed bearing assembly of claim 1 , wherein the seal lip comprises a radial seal lip.
12. The sealed bearing assembly of claim 11 , wherein the seal member includes a metal core, and a vulcanized rubber material attached to at least a radially inner portion of the metal core, and wherein the seal lip is formed of the vulcanized rubber material.
13. The sealed bearing assembly of claim 1 , wherein at least one of the seal sliding surface and the protrusion has undulations formed by shot peening.
14. The sealed bearing assembly of claim 13 , wherein the seal member includes a metal core, and a vulcanized rubber material attached to at least a radially inner portion of the metal core, and wherein the seal lip is formed of the vulcanized rubber material.
15. The sealed bearing assembly of claim 1 , wherein the sealed bearing assembly supports a rotary portion of one of a transmission, a differential, a constant-velocity joint, a propeller shaft, and a turbocharger, of a vehicle, a machine tool, a wind generator, and a wheel bearing.
16. The sealed bearing assembly of claim 15 , wherein the seal member includes a metal core, and a vulcanized rubber material attached to at least a radially inner portion of the metal core, and wherein the seal lip is formed of the vulcanized rubber material.
17. The sealed bearing assembly of claim 1 , wherein:
the bearing includes an inner race and an outer race, and
the seal sliding surface is on an outer periphery of the inner race.