Shaft bearing having improved seal arrangement

摘要

A bearing assembly includes an inner ring assembly defining a bore for receiving a shaft, and an outer ring assembly disposed radially outward from the inner ring assembly. A plurality of rotatable bearing elements are disposed between the inner and outer rings and permit the rotation of the shaft and inner ring relative to the outer ring. An annular member extends from the outer ring assembly radially inward toward the inner ring assembly. The annular member is secured to a housing surrounding the outer ring and axially bounds an area between the inner ring and the outer ring in which the plurality of rotatable bearing elements are disposed. A first seal is disposed outside the bearing area to seal a chamber between the annular member and the inner ring. The first seal permits egress of lubricant from the chamber but inhibits ingress of foreign matter therein. A second seal is disposed proximate the area and permits egress of lubricant between the inner ring and the annular member from the bearing area into the chamber, creating a lubricant dam between the first seal and the second seal.