Abstract: Construction of a rolling bearing unit with a combined seal ring that enables press fitting of a cylindrical section 15 of a slinger 13 to be pressure fitted on to a slinger fitting surface 20 of an inner ring 19a without losing the seal between the slinger fitting surface 20 and the cylindrical section 15 is achieved. Of the surface of the inner ring 19a, the continuous section that comprises a portion corresponding to the slinger fitting surface portion 20, a portion corresponding to the chamfered section 25a and a joining section 27a between these portions are simultaneously ground with a formed grindstone. As a result, the continuous section is entirely formed into a flat surface with no non-differential corners in the cross section, or in other words, with no sharp corners.

Abstract: Construction of a rolling bearing unit with a combined seal ring that enables press fitting of a cylindrical section 15 of a slinger 13 to be pressure fitted on to a slinger fitting surface 20 of an inner ring 19a without losing the seal between the slinger fitting surface 20 and the cylindrical section 15 is achieved. Of the surface of the inner ring 19a, the continuous section that comprises a portion corresponding to the slinger fitting surface portion 20, a portion corresponding to the chamfered section 25a and a joining section 27a between these portions are simultaneously ground with a formed grindstone. As a result, the continuous section is entirely formed into a flat surface with no non-differential corners in the cross section, or in other words, with no sharp corners.