WHEEL BEARING DEVICE AND PRELOAD-CONTROLLING METHOD THEREFOR

摘要

[Problem] To provide a wheel bearing device designed for improved durability that effectively limits swage cracking of the base of the swaged part of the hub ring during swaging and generation of cracks during use. [Solution] On the inner splined part (22) of a coupler ring (21), multiple spline flutes (22a) and spline ridges (22b) are alternately formed and mesh with a hub splined part (23) of the small diameter part (4b) of a hub ring (4), the hub splined part comprising multiple spline flutes (23a) and spline ridges (23b). The edge faces of the spline ridges (23b) are formed as a single arc having a prescribed radius of curvature (R). The radius of curvature (R) is set to be larger than a dimension (A) from the inner end face of the coupler ring (21) to the edge (B) of the spline ridge (R > A) and to be larger than the height (h) of the spline ridges (23b) (R > h). The internal diameter (Db) of the spline ridges (22b) is larger than the flute radius (Da) of the spline flutes (23a) and the difference in diameter ?D is set to be 1.0 mm or less.