| 摘要 |
PROBLEM TO BE SOLVED: To provide a wheel supporting rolling bearing unit which is constructed to prevent a cover from falling off from the axial inner end of an outer ring when pressure rise occurs in an internal space.SOLUTION: A cover 16a is constituted by a fitting cylindrical part 17a shaped cylindrical, an inner-diameter side folded-back cylindrical part 22 folded back axially outward from the axial inner edge of the fitting cylindrical part 17a, and a bottom plate part 18a elongated radially inward from the axial outer edge of the inner-diameter side folded-back cylindrical part 22. The whole bottom plate part 18a is formed as a partially spherical convex which is gradually bend axially inward as extending radially inward. In the axial-inner-end inner peripheral face of an outer ring 2a at a position where it matches the outer peripheral edge of the bottom plate part 18a with respect to the axial direction, a recessed groove 23 is formed throughout its periphery. When pressure rise occurs in an internal space 15, the bottom plate part 18a is deformed to be diameter-enlarged while being crushed axially inward, so that a protruded strip part 24 formed on the fitting cylindrical part 17a enters into the recessed groove 23.SELECTED DRAWING: Figure 1 |
